OpenCloudOS-Kernel/drivers/i3c/master.c

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i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2018 Cadence Design Systems Inc.
*
* Author: Boris Brezillon <boris.brezillon@bootlin.com>
*/
#include <linux/atomic.h>
#include <linux/bug.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include "internals.h"
static DEFINE_IDR(i3c_bus_idr);
static DEFINE_MUTEX(i3c_core_lock);
/**
* i3c_bus_maintenance_lock - Lock the bus for a maintenance operation
* @bus: I3C bus to take the lock on
*
* This function takes the bus lock so that no other operations can occur on
* the bus. This is needed for all kind of bus maintenance operation, like
* - enabling/disabling slave events
* - re-triggering DAA
* - changing the dynamic address of a device
* - relinquishing mastership
* - ...
*
* The reason for this kind of locking is that we don't want drivers and core
* logic to rely on I3C device information that could be changed behind their
* back.
*/
static void i3c_bus_maintenance_lock(struct i3c_bus *bus)
{
down_write(&bus->lock);
}
/**
* i3c_bus_maintenance_unlock - Release the bus lock after a maintenance
* operation
* @bus: I3C bus to release the lock on
*
* Should be called when the bus maintenance operation is done. See
* i3c_bus_maintenance_lock() for more details on what these maintenance
* operations are.
*/
static void i3c_bus_maintenance_unlock(struct i3c_bus *bus)
{
up_write(&bus->lock);
}
/**
* i3c_bus_normaluse_lock - Lock the bus for a normal operation
* @bus: I3C bus to take the lock on
*
* This function takes the bus lock for any operation that is not a maintenance
* operation (see i3c_bus_maintenance_lock() for a non-exhaustive list of
* maintenance operations). Basically all communications with I3C devices are
* normal operations (HDR, SDR transfers or CCC commands that do not change bus
* state or I3C dynamic address).
*
* Note that this lock is not guaranteeing serialization of normal operations.
* In other words, transfer requests passed to the I3C master can be submitted
* in parallel and I3C master drivers have to use their own locking to make
* sure two different communications are not inter-mixed, or access to the
* output/input queue is not done while the engine is busy.
*/
void i3c_bus_normaluse_lock(struct i3c_bus *bus)
{
down_read(&bus->lock);
}
/**
* i3c_bus_normaluse_unlock - Release the bus lock after a normal operation
* @bus: I3C bus to release the lock on
*
* Should be called when a normal operation is done. See
* i3c_bus_normaluse_lock() for more details on what these normal operations
* are.
*/
void i3c_bus_normaluse_unlock(struct i3c_bus *bus)
{
up_read(&bus->lock);
}
static struct i3c_master_controller *
i3c_bus_to_i3c_master(struct i3c_bus *i3cbus)
{
return container_of(i3cbus, struct i3c_master_controller, bus);
}
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
static struct i3c_master_controller *dev_to_i3cmaster(struct device *dev)
{
return container_of(dev, struct i3c_master_controller, dev);
}
static const struct device_type i3c_device_type;
static struct i3c_bus *dev_to_i3cbus(struct device *dev)
{
struct i3c_master_controller *master;
if (dev->type == &i3c_device_type)
return dev_to_i3cdev(dev)->bus;
master = dev_to_i3cmaster(dev);
return &master->bus;
}
static struct i3c_dev_desc *dev_to_i3cdesc(struct device *dev)
{
struct i3c_master_controller *master;
if (dev->type == &i3c_device_type)
return dev_to_i3cdev(dev)->desc;
master = dev_to_i3cmaster(dev);
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
return master->this;
}
static ssize_t bcr_show(struct device *dev,
struct device_attribute *da,
char *buf)
{
struct i3c_bus *bus = dev_to_i3cbus(dev);
struct i3c_dev_desc *desc;
ssize_t ret;
i3c_bus_normaluse_lock(bus);
desc = dev_to_i3cdesc(dev);
ret = sprintf(buf, "%x\n", desc->info.bcr);
i3c_bus_normaluse_unlock(bus);
return ret;
}
static DEVICE_ATTR_RO(bcr);
static ssize_t dcr_show(struct device *dev,
struct device_attribute *da,
char *buf)
{
struct i3c_bus *bus = dev_to_i3cbus(dev);
struct i3c_dev_desc *desc;
ssize_t ret;
i3c_bus_normaluse_lock(bus);
desc = dev_to_i3cdesc(dev);
ret = sprintf(buf, "%x\n", desc->info.dcr);
i3c_bus_normaluse_unlock(bus);
return ret;
}
static DEVICE_ATTR_RO(dcr);
static ssize_t pid_show(struct device *dev,
struct device_attribute *da,
char *buf)
{
struct i3c_bus *bus = dev_to_i3cbus(dev);
struct i3c_dev_desc *desc;
ssize_t ret;
i3c_bus_normaluse_lock(bus);
desc = dev_to_i3cdesc(dev);
ret = sprintf(buf, "%llx\n", desc->info.pid);
i3c_bus_normaluse_unlock(bus);
return ret;
}
static DEVICE_ATTR_RO(pid);
static ssize_t dynamic_address_show(struct device *dev,
struct device_attribute *da,
char *buf)
{
struct i3c_bus *bus = dev_to_i3cbus(dev);
struct i3c_dev_desc *desc;
ssize_t ret;
i3c_bus_normaluse_lock(bus);
desc = dev_to_i3cdesc(dev);
ret = sprintf(buf, "%02x\n", desc->info.dyn_addr);
i3c_bus_normaluse_unlock(bus);
return ret;
}
static DEVICE_ATTR_RO(dynamic_address);
static const char * const hdrcap_strings[] = {
"hdr-ddr", "hdr-tsp", "hdr-tsl",
};
static ssize_t hdrcap_show(struct device *dev,
struct device_attribute *da,
char *buf)
{
struct i3c_bus *bus = dev_to_i3cbus(dev);
struct i3c_dev_desc *desc;
ssize_t offset = 0, ret;
unsigned long caps;
int mode;
i3c_bus_normaluse_lock(bus);
desc = dev_to_i3cdesc(dev);
caps = desc->info.hdr_cap;
for_each_set_bit(mode, &caps, 8) {
if (mode >= ARRAY_SIZE(hdrcap_strings))
break;
if (!hdrcap_strings[mode])
continue;
ret = sprintf(buf + offset, offset ? " %s" : "%s",
hdrcap_strings[mode]);
if (ret < 0)
goto out;
offset += ret;
}
ret = sprintf(buf + offset, "\n");
if (ret < 0)
goto out;
ret = offset + ret;
out:
i3c_bus_normaluse_unlock(bus);
return ret;
}
static DEVICE_ATTR_RO(hdrcap);
static ssize_t modalias_show(struct device *dev,
struct device_attribute *da, char *buf)
{
struct i3c_device *i3c = dev_to_i3cdev(dev);
struct i3c_device_info devinfo;
u16 manuf, part, ext;
i3c_device_get_info(i3c, &devinfo);
manuf = I3C_PID_MANUF_ID(devinfo.pid);
part = I3C_PID_PART_ID(devinfo.pid);
ext = I3C_PID_EXTRA_INFO(devinfo.pid);
if (I3C_PID_RND_LOWER_32BITS(devinfo.pid))
return sprintf(buf, "i3c:dcr%02Xmanuf%04X", devinfo.dcr,
manuf);
return sprintf(buf, "i3c:dcr%02Xmanuf%04Xpart%04Xext%04X",
devinfo.dcr, manuf, part, ext);
}
static DEVICE_ATTR_RO(modalias);
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
static struct attribute *i3c_device_attrs[] = {
&dev_attr_bcr.attr,
&dev_attr_dcr.attr,
&dev_attr_pid.attr,
&dev_attr_dynamic_address.attr,
&dev_attr_hdrcap.attr,
&dev_attr_modalias.attr,
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
NULL,
};
ATTRIBUTE_GROUPS(i3c_device);
static int i3c_device_uevent(struct device *dev, struct kobj_uevent_env *env)
{
struct i3c_device *i3cdev = dev_to_i3cdev(dev);
struct i3c_device_info devinfo;
u16 manuf, part, ext;
i3c_device_get_info(i3cdev, &devinfo);
manuf = I3C_PID_MANUF_ID(devinfo.pid);
part = I3C_PID_PART_ID(devinfo.pid);
ext = I3C_PID_EXTRA_INFO(devinfo.pid);
if (I3C_PID_RND_LOWER_32BITS(devinfo.pid))
return add_uevent_var(env, "MODALIAS=i3c:dcr%02Xmanuf%04X",
devinfo.dcr, manuf);
return add_uevent_var(env,
"MODALIAS=i3c:dcr%02Xmanuf%04Xpart%04Xext%04X",
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
devinfo.dcr, manuf, part, ext);
}
static const struct device_type i3c_device_type = {
.groups = i3c_device_groups,
.uevent = i3c_device_uevent,
};
static int i3c_device_match(struct device *dev, struct device_driver *drv)
{
struct i3c_device *i3cdev;
struct i3c_driver *i3cdrv;
if (dev->type != &i3c_device_type)
return 0;
i3cdev = dev_to_i3cdev(dev);
i3cdrv = drv_to_i3cdrv(drv);
if (i3c_device_match_id(i3cdev, i3cdrv->id_table))
return 1;
return 0;
}
static int i3c_device_probe(struct device *dev)
{
struct i3c_device *i3cdev = dev_to_i3cdev(dev);
struct i3c_driver *driver = drv_to_i3cdrv(dev->driver);
return driver->probe(i3cdev);
}
bus: Make remove callback return void The driver core ignores the return value of this callback because there is only little it can do when a device disappears. This is the final bit of a long lasting cleanup quest where several buses were converted to also return void from their remove callback. Additionally some resource leaks were fixed that were caused by drivers returning an error code in the expectation that the driver won't go away. With struct bus_type::remove returning void it's prevented that newly implemented buses return an ignored error code and so don't anticipate wrong expectations for driver authors. Reviewed-by: Tom Rix <trix@redhat.com> (For fpga) Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Cornelia Huck <cohuck@redhat.com> (For drivers/s390 and drivers/vfio) Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> (For ARM, Amba and related parts) Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Chen-Yu Tsai <wens@csie.org> (for sunxi-rsb) Acked-by: Pali Rohár <pali@kernel.org> Acked-by: Mauro Carvalho Chehab <mchehab@kernel.org> (for media) Acked-by: Hans de Goede <hdegoede@redhat.com> (For drivers/platform) Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Acked-By: Vinod Koul <vkoul@kernel.org> Acked-by: Juergen Gross <jgross@suse.com> (For xen) Acked-by: Lee Jones <lee.jones@linaro.org> (For mfd) Acked-by: Johannes Thumshirn <jth@kernel.org> (For mcb) Acked-by: Johan Hovold <johan@kernel.org> Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> (For slimbus) Acked-by: Kirti Wankhede <kwankhede@nvidia.com> (For vfio) Acked-by: Maximilian Luz <luzmaximilian@gmail.com> Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> (For ulpi and typec) Acked-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com> (For ipack) Acked-by: Geoff Levand <geoff@infradead.org> (For ps3) Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com> (For thunderbolt) Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> (For intel_th) Acked-by: Dominik Brodowski <linux@dominikbrodowski.net> (For pcmcia) Acked-by: Rafael J. Wysocki <rafael@kernel.org> (For ACPI) Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org> (rpmsg and apr) Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> (For intel-ish-hid) Acked-by: Dan Williams <dan.j.williams@intel.com> (For CXL, DAX, and NVDIMM) Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com> (For isa) Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (For firewire) Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> (For hid) Acked-by: Thorsten Scherer <t.scherer@eckelmann.de> (For siox) Acked-by: Sven Van Asbroeck <TheSven73@gmail.com> (For anybuss) Acked-by: Ulf Hansson <ulf.hansson@linaro.org> (For MMC) Acked-by: Wolfram Sang <wsa@kernel.org> # for I2C Acked-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Finn Thain <fthain@linux-m68k.org> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20210713193522.1770306-6-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-14 03:35:22 +08:00
static void i3c_device_remove(struct device *dev)
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
{
struct i3c_device *i3cdev = dev_to_i3cdev(dev);
struct i3c_driver *driver = drv_to_i3cdrv(dev->driver);
if (driver->remove)
driver->remove(i3cdev);
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
i3c_device_free_ibi(i3cdev);
}
struct bus_type i3c_bus_type = {
.name = "i3c",
.match = i3c_device_match,
.probe = i3c_device_probe,
.remove = i3c_device_remove,
};
static enum i3c_addr_slot_status
i3c_bus_get_addr_slot_status(struct i3c_bus *bus, u16 addr)
{
unsigned long status;
int bitpos = addr * 2;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
if (addr > I2C_MAX_ADDR)
return I3C_ADDR_SLOT_RSVD;
status = bus->addrslots[bitpos / BITS_PER_LONG];
status >>= bitpos % BITS_PER_LONG;
return status & I3C_ADDR_SLOT_STATUS_MASK;
}
static void i3c_bus_set_addr_slot_status(struct i3c_bus *bus, u16 addr,
enum i3c_addr_slot_status status)
{
int bitpos = addr * 2;
unsigned long *ptr;
if (addr > I2C_MAX_ADDR)
return;
ptr = bus->addrslots + (bitpos / BITS_PER_LONG);
*ptr &= ~((unsigned long)I3C_ADDR_SLOT_STATUS_MASK <<
(bitpos % BITS_PER_LONG));
*ptr |= (unsigned long)status << (bitpos % BITS_PER_LONG);
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
}
static bool i3c_bus_dev_addr_is_avail(struct i3c_bus *bus, u8 addr)
{
enum i3c_addr_slot_status status;
status = i3c_bus_get_addr_slot_status(bus, addr);
return status == I3C_ADDR_SLOT_FREE;
}
static int i3c_bus_get_free_addr(struct i3c_bus *bus, u8 start_addr)
{
enum i3c_addr_slot_status status;
u8 addr;
for (addr = start_addr; addr < I3C_MAX_ADDR; addr++) {
status = i3c_bus_get_addr_slot_status(bus, addr);
if (status == I3C_ADDR_SLOT_FREE)
return addr;
}
return -ENOMEM;
}
static void i3c_bus_init_addrslots(struct i3c_bus *bus)
{
int i;
/* Addresses 0 to 7 are reserved. */
for (i = 0; i < 8; i++)
i3c_bus_set_addr_slot_status(bus, i, I3C_ADDR_SLOT_RSVD);
/*
* Reserve broadcast address and all addresses that might collide
* with the broadcast address when facing a single bit error.
*/
i3c_bus_set_addr_slot_status(bus, I3C_BROADCAST_ADDR,
I3C_ADDR_SLOT_RSVD);
for (i = 0; i < 7; i++)
i3c_bus_set_addr_slot_status(bus, I3C_BROADCAST_ADDR ^ BIT(i),
I3C_ADDR_SLOT_RSVD);
}
static void i3c_bus_cleanup(struct i3c_bus *i3cbus)
{
mutex_lock(&i3c_core_lock);
idr_remove(&i3c_bus_idr, i3cbus->id);
mutex_unlock(&i3c_core_lock);
}
static int i3c_bus_init(struct i3c_bus *i3cbus)
{
int ret;
init_rwsem(&i3cbus->lock);
INIT_LIST_HEAD(&i3cbus->devs.i2c);
INIT_LIST_HEAD(&i3cbus->devs.i3c);
i3c_bus_init_addrslots(i3cbus);
i3cbus->mode = I3C_BUS_MODE_PURE;
mutex_lock(&i3c_core_lock);
ret = idr_alloc(&i3c_bus_idr, i3cbus, 0, 0, GFP_KERNEL);
mutex_unlock(&i3c_core_lock);
if (ret < 0)
return ret;
i3cbus->id = ret;
return 0;
}
static const char * const i3c_bus_mode_strings[] = {
[I3C_BUS_MODE_PURE] = "pure",
[I3C_BUS_MODE_MIXED_FAST] = "mixed-fast",
[I3C_BUS_MODE_MIXED_LIMITED] = "mixed-limited",
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
[I3C_BUS_MODE_MIXED_SLOW] = "mixed-slow",
};
static ssize_t mode_show(struct device *dev,
struct device_attribute *da,
char *buf)
{
struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
ssize_t ret;
i3c_bus_normaluse_lock(i3cbus);
if (i3cbus->mode < 0 ||
i3cbus->mode >= ARRAY_SIZE(i3c_bus_mode_strings) ||
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
!i3c_bus_mode_strings[i3cbus->mode])
ret = sprintf(buf, "unknown\n");
else
ret = sprintf(buf, "%s\n", i3c_bus_mode_strings[i3cbus->mode]);
i3c_bus_normaluse_unlock(i3cbus);
return ret;
}
static DEVICE_ATTR_RO(mode);
static ssize_t current_master_show(struct device *dev,
struct device_attribute *da,
char *buf)
{
struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
ssize_t ret;
i3c_bus_normaluse_lock(i3cbus);
ret = sprintf(buf, "%d-%llx\n", i3cbus->id,
i3cbus->cur_master->info.pid);
i3c_bus_normaluse_unlock(i3cbus);
return ret;
}
static DEVICE_ATTR_RO(current_master);
static ssize_t i3c_scl_frequency_show(struct device *dev,
struct device_attribute *da,
char *buf)
{
struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
ssize_t ret;
i3c_bus_normaluse_lock(i3cbus);
ret = sprintf(buf, "%ld\n", i3cbus->scl_rate.i3c);
i3c_bus_normaluse_unlock(i3cbus);
return ret;
}
static DEVICE_ATTR_RO(i3c_scl_frequency);
static ssize_t i2c_scl_frequency_show(struct device *dev,
struct device_attribute *da,
char *buf)
{
struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
ssize_t ret;
i3c_bus_normaluse_lock(i3cbus);
ret = sprintf(buf, "%ld\n", i3cbus->scl_rate.i2c);
i3c_bus_normaluse_unlock(i3cbus);
return ret;
}
static DEVICE_ATTR_RO(i2c_scl_frequency);
static struct attribute *i3c_masterdev_attrs[] = {
&dev_attr_mode.attr,
&dev_attr_current_master.attr,
&dev_attr_i3c_scl_frequency.attr,
&dev_attr_i2c_scl_frequency.attr,
&dev_attr_bcr.attr,
&dev_attr_dcr.attr,
&dev_attr_pid.attr,
&dev_attr_dynamic_address.attr,
&dev_attr_hdrcap.attr,
NULL,
};
ATTRIBUTE_GROUPS(i3c_masterdev);
static void i3c_masterdev_release(struct device *dev)
{
struct i3c_master_controller *master = dev_to_i3cmaster(dev);
struct i3c_bus *bus = dev_to_i3cbus(dev);
if (master->wq)
destroy_workqueue(master->wq);
WARN_ON(!list_empty(&bus->devs.i2c) || !list_empty(&bus->devs.i3c));
i3c_bus_cleanup(bus);
of_node_put(dev->of_node);
}
static const struct device_type i3c_masterdev_type = {
.groups = i3c_masterdev_groups,
};
static int i3c_bus_set_mode(struct i3c_bus *i3cbus, enum i3c_bus_mode mode,
unsigned long max_i2c_scl_rate)
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
{
struct i3c_master_controller *master = i3c_bus_to_i3c_master(i3cbus);
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
i3cbus->mode = mode;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
switch (i3cbus->mode) {
case I3C_BUS_MODE_PURE:
if (!i3cbus->scl_rate.i3c)
i3cbus->scl_rate.i3c = I3C_BUS_TYP_I3C_SCL_RATE;
break;
case I3C_BUS_MODE_MIXED_FAST:
case I3C_BUS_MODE_MIXED_LIMITED:
if (!i3cbus->scl_rate.i3c)
i3cbus->scl_rate.i3c = I3C_BUS_TYP_I3C_SCL_RATE;
if (!i3cbus->scl_rate.i2c)
i3cbus->scl_rate.i2c = max_i2c_scl_rate;
break;
case I3C_BUS_MODE_MIXED_SLOW:
if (!i3cbus->scl_rate.i2c)
i3cbus->scl_rate.i2c = max_i2c_scl_rate;
if (!i3cbus->scl_rate.i3c ||
i3cbus->scl_rate.i3c > i3cbus->scl_rate.i2c)
i3cbus->scl_rate.i3c = i3cbus->scl_rate.i2c;
break;
default:
return -EINVAL;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
}
dev_dbg(&master->dev, "i2c-scl = %ld Hz i3c-scl = %ld Hz\n",
i3cbus->scl_rate.i2c, i3cbus->scl_rate.i3c);
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
/*
* I3C/I2C frequency may have been overridden, check that user-provided
* values are not exceeding max possible frequency.
*/
if (i3cbus->scl_rate.i3c > I3C_BUS_MAX_I3C_SCL_RATE ||
i3cbus->scl_rate.i2c > I3C_BUS_I2C_FM_PLUS_SCL_RATE)
return -EINVAL;
return 0;
}
static struct i3c_master_controller *
i2c_adapter_to_i3c_master(struct i2c_adapter *adap)
{
return container_of(adap, struct i3c_master_controller, i2c);
}
static struct i2c_adapter *
i3c_master_to_i2c_adapter(struct i3c_master_controller *master)
{
return &master->i2c;
}
static void i3c_master_free_i2c_dev(struct i2c_dev_desc *dev)
{
kfree(dev);
}
static struct i2c_dev_desc *
i3c_master_alloc_i2c_dev(struct i3c_master_controller *master,
u16 addr, u8 lvr)
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
{
struct i2c_dev_desc *dev;
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return ERR_PTR(-ENOMEM);
dev->common.master = master;
dev->addr = addr;
dev->lvr = lvr;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
return dev;
}
static void *i3c_ccc_cmd_dest_init(struct i3c_ccc_cmd_dest *dest, u8 addr,
u16 payloadlen)
{
dest->addr = addr;
dest->payload.len = payloadlen;
if (payloadlen)
dest->payload.data = kzalloc(payloadlen, GFP_KERNEL);
else
dest->payload.data = NULL;
return dest->payload.data;
}
static void i3c_ccc_cmd_dest_cleanup(struct i3c_ccc_cmd_dest *dest)
{
kfree(dest->payload.data);
}
static void i3c_ccc_cmd_init(struct i3c_ccc_cmd *cmd, bool rnw, u8 id,
struct i3c_ccc_cmd_dest *dests,
unsigned int ndests)
{
cmd->rnw = rnw ? 1 : 0;
cmd->id = id;
cmd->dests = dests;
cmd->ndests = ndests;
cmd->err = I3C_ERROR_UNKNOWN;
}
static int i3c_master_send_ccc_cmd_locked(struct i3c_master_controller *master,
struct i3c_ccc_cmd *cmd)
{
int ret;
if (!cmd || !master)
return -EINVAL;
if (WARN_ON(master->init_done &&
!rwsem_is_locked(&master->bus.lock)))
return -EINVAL;
if (!master->ops->send_ccc_cmd)
return -ENOTSUPP;
if ((cmd->id & I3C_CCC_DIRECT) && (!cmd->dests || !cmd->ndests))
return -EINVAL;
if (master->ops->supports_ccc_cmd &&
!master->ops->supports_ccc_cmd(master, cmd))
return -ENOTSUPP;
ret = master->ops->send_ccc_cmd(master, cmd);
if (ret) {
if (cmd->err != I3C_ERROR_UNKNOWN)
return cmd->err;
return ret;
}
return 0;
}
static struct i2c_dev_desc *
i3c_master_find_i2c_dev_by_addr(const struct i3c_master_controller *master,
u16 addr)
{
struct i2c_dev_desc *dev;
i3c_bus_for_each_i2cdev(&master->bus, dev) {
if (dev->addr == addr)
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
return dev;
}
return NULL;
}
/**
* i3c_master_get_free_addr() - get a free address on the bus
* @master: I3C master object
* @start_addr: where to start searching
*
* This function must be called with the bus lock held in write mode.
*
* Return: the first free address starting at @start_addr (included) or -ENOMEM
* if there's no more address available.
*/
int i3c_master_get_free_addr(struct i3c_master_controller *master,
u8 start_addr)
{
return i3c_bus_get_free_addr(&master->bus, start_addr);
}
EXPORT_SYMBOL_GPL(i3c_master_get_free_addr);
static void i3c_device_release(struct device *dev)
{
struct i3c_device *i3cdev = dev_to_i3cdev(dev);
WARN_ON(i3cdev->desc);
of_node_put(i3cdev->dev.of_node);
kfree(i3cdev);
}
static void i3c_master_free_i3c_dev(struct i3c_dev_desc *dev)
{
kfree(dev);
}
static struct i3c_dev_desc *
i3c_master_alloc_i3c_dev(struct i3c_master_controller *master,
const struct i3c_device_info *info)
{
struct i3c_dev_desc *dev;
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return ERR_PTR(-ENOMEM);
dev->common.master = master;
dev->info = *info;
mutex_init(&dev->ibi_lock);
return dev;
}
static int i3c_master_rstdaa_locked(struct i3c_master_controller *master,
u8 addr)
{
enum i3c_addr_slot_status addrstat;
struct i3c_ccc_cmd_dest dest;
struct i3c_ccc_cmd cmd;
int ret;
if (!master)
return -EINVAL;
addrstat = i3c_bus_get_addr_slot_status(&master->bus, addr);
if (addr != I3C_BROADCAST_ADDR && addrstat != I3C_ADDR_SLOT_I3C_DEV)
return -EINVAL;
i3c_ccc_cmd_dest_init(&dest, addr, 0);
i3c_ccc_cmd_init(&cmd, false,
I3C_CCC_RSTDAA(addr == I3C_BROADCAST_ADDR),
&dest, 1);
ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
i3c_ccc_cmd_dest_cleanup(&dest);
return ret;
}
/**
* i3c_master_entdaa_locked() - start a DAA (Dynamic Address Assignment)
* procedure
* @master: master used to send frames on the bus
*
* Send a ENTDAA CCC command to start a DAA procedure.
*
* Note that this function only sends the ENTDAA CCC command, all the logic
* behind dynamic address assignment has to be handled in the I3C master
* driver.
*
* This function must be called with the bus lock held in write mode.
*
* Return: 0 in case of success, a positive I3C error code if the error is
* one of the official Mx error codes, and a negative error code otherwise.
*/
int i3c_master_entdaa_locked(struct i3c_master_controller *master)
{
struct i3c_ccc_cmd_dest dest;
struct i3c_ccc_cmd cmd;
int ret;
i3c_ccc_cmd_dest_init(&dest, I3C_BROADCAST_ADDR, 0);
i3c_ccc_cmd_init(&cmd, false, I3C_CCC_ENTDAA, &dest, 1);
ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
i3c_ccc_cmd_dest_cleanup(&dest);
return ret;
}
EXPORT_SYMBOL_GPL(i3c_master_entdaa_locked);
static int i3c_master_enec_disec_locked(struct i3c_master_controller *master,
u8 addr, bool enable, u8 evts)
{
struct i3c_ccc_events *events;
struct i3c_ccc_cmd_dest dest;
struct i3c_ccc_cmd cmd;
int ret;
events = i3c_ccc_cmd_dest_init(&dest, addr, sizeof(*events));
if (!events)
return -ENOMEM;
events->events = evts;
i3c_ccc_cmd_init(&cmd, false,
enable ?
I3C_CCC_ENEC(addr == I3C_BROADCAST_ADDR) :
I3C_CCC_DISEC(addr == I3C_BROADCAST_ADDR),
&dest, 1);
ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
i3c_ccc_cmd_dest_cleanup(&dest);
return ret;
}
/**
* i3c_master_disec_locked() - send a DISEC CCC command
* @master: master used to send frames on the bus
* @addr: a valid I3C slave address or %I3C_BROADCAST_ADDR
* @evts: events to disable
*
* Send a DISEC CCC command to disable some or all events coming from a
* specific slave, or all devices if @addr is %I3C_BROADCAST_ADDR.
*
* This function must be called with the bus lock held in write mode.
*
* Return: 0 in case of success, a positive I3C error code if the error is
* one of the official Mx error codes, and a negative error code otherwise.
*/
int i3c_master_disec_locked(struct i3c_master_controller *master, u8 addr,
u8 evts)
{
return i3c_master_enec_disec_locked(master, addr, false, evts);
}
EXPORT_SYMBOL_GPL(i3c_master_disec_locked);
/**
* i3c_master_enec_locked() - send an ENEC CCC command
* @master: master used to send frames on the bus
* @addr: a valid I3C slave address or %I3C_BROADCAST_ADDR
* @evts: events to disable
*
* Sends an ENEC CCC command to enable some or all events coming from a
* specific slave, or all devices if @addr is %I3C_BROADCAST_ADDR.
*
* This function must be called with the bus lock held in write mode.
*
* Return: 0 in case of success, a positive I3C error code if the error is
* one of the official Mx error codes, and a negative error code otherwise.
*/
int i3c_master_enec_locked(struct i3c_master_controller *master, u8 addr,
u8 evts)
{
return i3c_master_enec_disec_locked(master, addr, true, evts);
}
EXPORT_SYMBOL_GPL(i3c_master_enec_locked);
/**
* i3c_master_defslvs_locked() - send a DEFSLVS CCC command
* @master: master used to send frames on the bus
*
* Send a DEFSLVS CCC command containing all the devices known to the @master.
* This is useful when you have secondary masters on the bus to propagate
* device information.
*
* This should be called after all I3C devices have been discovered (in other
* words, after the DAA procedure has finished) and instantiated in
* &i3c_master_controller_ops->bus_init().
* It should also be called if a master ACKed an Hot-Join request and assigned
* a dynamic address to the device joining the bus.
*
* This function must be called with the bus lock held in write mode.
*
* Return: 0 in case of success, a positive I3C error code if the error is
* one of the official Mx error codes, and a negative error code otherwise.
*/
int i3c_master_defslvs_locked(struct i3c_master_controller *master)
{
struct i3c_ccc_defslvs *defslvs;
struct i3c_ccc_dev_desc *desc;
struct i3c_ccc_cmd_dest dest;
struct i3c_dev_desc *i3cdev;
struct i2c_dev_desc *i2cdev;
struct i3c_ccc_cmd cmd;
struct i3c_bus *bus;
bool send = false;
int ndevs = 0, ret;
if (!master)
return -EINVAL;
bus = i3c_master_get_bus(master);
i3c_bus_for_each_i3cdev(bus, i3cdev) {
ndevs++;
if (i3cdev == master->this)
continue;
if (I3C_BCR_DEVICE_ROLE(i3cdev->info.bcr) ==
I3C_BCR_I3C_MASTER)
send = true;
}
/* No other master on the bus, skip DEFSLVS. */
if (!send)
return 0;
i3c_bus_for_each_i2cdev(bus, i2cdev)
ndevs++;
defslvs = i3c_ccc_cmd_dest_init(&dest, I3C_BROADCAST_ADDR,
struct_size(defslvs, slaves,
ndevs - 1));
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
if (!defslvs)
return -ENOMEM;
defslvs->count = ndevs;
defslvs->master.bcr = master->this->info.bcr;
defslvs->master.dcr = master->this->info.dcr;
defslvs->master.dyn_addr = master->this->info.dyn_addr << 1;
defslvs->master.static_addr = I3C_BROADCAST_ADDR << 1;
desc = defslvs->slaves;
i3c_bus_for_each_i2cdev(bus, i2cdev) {
desc->lvr = i2cdev->lvr;
desc->static_addr = i2cdev->addr << 1;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
desc++;
}
i3c_bus_for_each_i3cdev(bus, i3cdev) {
/* Skip the I3C dev representing this master. */
if (i3cdev == master->this)
continue;
desc->bcr = i3cdev->info.bcr;
desc->dcr = i3cdev->info.dcr;
desc->dyn_addr = i3cdev->info.dyn_addr << 1;
desc->static_addr = i3cdev->info.static_addr << 1;
desc++;
}
i3c_ccc_cmd_init(&cmd, false, I3C_CCC_DEFSLVS, &dest, 1);
ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
i3c_ccc_cmd_dest_cleanup(&dest);
return ret;
}
EXPORT_SYMBOL_GPL(i3c_master_defslvs_locked);
static int i3c_master_setda_locked(struct i3c_master_controller *master,
u8 oldaddr, u8 newaddr, bool setdasa)
{
struct i3c_ccc_cmd_dest dest;
struct i3c_ccc_setda *setda;
struct i3c_ccc_cmd cmd;
int ret;
if (!oldaddr || !newaddr)
return -EINVAL;
setda = i3c_ccc_cmd_dest_init(&dest, oldaddr, sizeof(*setda));
if (!setda)
return -ENOMEM;
setda->addr = newaddr << 1;
i3c_ccc_cmd_init(&cmd, false,
setdasa ? I3C_CCC_SETDASA : I3C_CCC_SETNEWDA,
&dest, 1);
ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
i3c_ccc_cmd_dest_cleanup(&dest);
return ret;
}
static int i3c_master_setdasa_locked(struct i3c_master_controller *master,
u8 static_addr, u8 dyn_addr)
{
return i3c_master_setda_locked(master, static_addr, dyn_addr, true);
}
static int i3c_master_setnewda_locked(struct i3c_master_controller *master,
u8 oldaddr, u8 newaddr)
{
return i3c_master_setda_locked(master, oldaddr, newaddr, false);
}
static int i3c_master_getmrl_locked(struct i3c_master_controller *master,
struct i3c_device_info *info)
{
struct i3c_ccc_cmd_dest dest;
struct i3c_ccc_mrl *mrl;
struct i3c_ccc_cmd cmd;
int ret;
mrl = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*mrl));
if (!mrl)
return -ENOMEM;
/*
* When the device does not have IBI payload GETMRL only returns 2
* bytes of data.
*/
if (!(info->bcr & I3C_BCR_IBI_PAYLOAD))
dest.payload.len -= 1;
i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETMRL, &dest, 1);
ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
if (ret)
goto out;
switch (dest.payload.len) {
case 3:
info->max_ibi_len = mrl->ibi_len;
fallthrough;
case 2:
info->max_read_len = be16_to_cpu(mrl->read_len);
break;
default:
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
ret = -EIO;
goto out;
}
out:
i3c_ccc_cmd_dest_cleanup(&dest);
return ret;
}
static int i3c_master_getmwl_locked(struct i3c_master_controller *master,
struct i3c_device_info *info)
{
struct i3c_ccc_cmd_dest dest;
struct i3c_ccc_mwl *mwl;
struct i3c_ccc_cmd cmd;
int ret;
mwl = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*mwl));
if (!mwl)
return -ENOMEM;
i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETMWL, &dest, 1);
ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
if (ret)
goto out;
if (dest.payload.len != sizeof(*mwl)) {
ret = -EIO;
goto out;
}
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
info->max_write_len = be16_to_cpu(mwl->len);
out:
i3c_ccc_cmd_dest_cleanup(&dest);
return ret;
}
static int i3c_master_getmxds_locked(struct i3c_master_controller *master,
struct i3c_device_info *info)
{
struct i3c_ccc_getmxds *getmaxds;
struct i3c_ccc_cmd_dest dest;
struct i3c_ccc_cmd cmd;
int ret;
getmaxds = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr,
sizeof(*getmaxds));
if (!getmaxds)
return -ENOMEM;
i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETMXDS, &dest, 1);
ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
if (ret)
goto out;
if (dest.payload.len != 2 && dest.payload.len != 5) {
ret = -EIO;
goto out;
}
info->max_read_ds = getmaxds->maxrd;
info->max_write_ds = getmaxds->maxwr;
if (dest.payload.len == 5)
info->max_read_turnaround = getmaxds->maxrdturn[0] |
((u32)getmaxds->maxrdturn[1] << 8) |
((u32)getmaxds->maxrdturn[2] << 16);
out:
i3c_ccc_cmd_dest_cleanup(&dest);
return ret;
}
static int i3c_master_gethdrcap_locked(struct i3c_master_controller *master,
struct i3c_device_info *info)
{
struct i3c_ccc_gethdrcap *gethdrcap;
struct i3c_ccc_cmd_dest dest;
struct i3c_ccc_cmd cmd;
int ret;
gethdrcap = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr,
sizeof(*gethdrcap));
if (!gethdrcap)
return -ENOMEM;
i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETHDRCAP, &dest, 1);
ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
if (ret)
goto out;
if (dest.payload.len != 1) {
ret = -EIO;
goto out;
}
info->hdr_cap = gethdrcap->modes;
out:
i3c_ccc_cmd_dest_cleanup(&dest);
return ret;
}
static int i3c_master_getpid_locked(struct i3c_master_controller *master,
struct i3c_device_info *info)
{
struct i3c_ccc_getpid *getpid;
struct i3c_ccc_cmd_dest dest;
struct i3c_ccc_cmd cmd;
int ret, i;
getpid = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*getpid));
if (!getpid)
return -ENOMEM;
i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETPID, &dest, 1);
ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
if (ret)
goto out;
info->pid = 0;
for (i = 0; i < sizeof(getpid->pid); i++) {
int sft = (sizeof(getpid->pid) - i - 1) * 8;
info->pid |= (u64)getpid->pid[i] << sft;
}
out:
i3c_ccc_cmd_dest_cleanup(&dest);
return ret;
}
static int i3c_master_getbcr_locked(struct i3c_master_controller *master,
struct i3c_device_info *info)
{
struct i3c_ccc_getbcr *getbcr;
struct i3c_ccc_cmd_dest dest;
struct i3c_ccc_cmd cmd;
int ret;
getbcr = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*getbcr));
if (!getbcr)
return -ENOMEM;
i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETBCR, &dest, 1);
ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
if (ret)
goto out;
info->bcr = getbcr->bcr;
out:
i3c_ccc_cmd_dest_cleanup(&dest);
return ret;
}
static int i3c_master_getdcr_locked(struct i3c_master_controller *master,
struct i3c_device_info *info)
{
struct i3c_ccc_getdcr *getdcr;
struct i3c_ccc_cmd_dest dest;
struct i3c_ccc_cmd cmd;
int ret;
getdcr = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*getdcr));
if (!getdcr)
return -ENOMEM;
i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETDCR, &dest, 1);
ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
if (ret)
goto out;
info->dcr = getdcr->dcr;
out:
i3c_ccc_cmd_dest_cleanup(&dest);
return ret;
}
static int i3c_master_retrieve_dev_info(struct i3c_dev_desc *dev)
{
struct i3c_master_controller *master = i3c_dev_get_master(dev);
enum i3c_addr_slot_status slot_status;
int ret;
if (!dev->info.dyn_addr)
return -EINVAL;
slot_status = i3c_bus_get_addr_slot_status(&master->bus,
dev->info.dyn_addr);
if (slot_status == I3C_ADDR_SLOT_RSVD ||
slot_status == I3C_ADDR_SLOT_I2C_DEV)
return -EINVAL;
ret = i3c_master_getpid_locked(master, &dev->info);
if (ret)
return ret;
ret = i3c_master_getbcr_locked(master, &dev->info);
if (ret)
return ret;
ret = i3c_master_getdcr_locked(master, &dev->info);
if (ret)
return ret;
if (dev->info.bcr & I3C_BCR_MAX_DATA_SPEED_LIM) {
ret = i3c_master_getmxds_locked(master, &dev->info);
if (ret)
return ret;
}
if (dev->info.bcr & I3C_BCR_IBI_PAYLOAD)
dev->info.max_ibi_len = 1;
i3c_master_getmrl_locked(master, &dev->info);
i3c_master_getmwl_locked(master, &dev->info);
if (dev->info.bcr & I3C_BCR_HDR_CAP) {
ret = i3c_master_gethdrcap_locked(master, &dev->info);
if (ret)
return ret;
}
return 0;
}
static void i3c_master_put_i3c_addrs(struct i3c_dev_desc *dev)
{
struct i3c_master_controller *master = i3c_dev_get_master(dev);
if (dev->info.static_addr)
i3c_bus_set_addr_slot_status(&master->bus,
dev->info.static_addr,
I3C_ADDR_SLOT_FREE);
if (dev->info.dyn_addr)
i3c_bus_set_addr_slot_status(&master->bus, dev->info.dyn_addr,
I3C_ADDR_SLOT_FREE);
if (dev->boardinfo && dev->boardinfo->init_dyn_addr)
i3c_bus_set_addr_slot_status(&master->bus, dev->info.dyn_addr,
I3C_ADDR_SLOT_FREE);
}
static int i3c_master_get_i3c_addrs(struct i3c_dev_desc *dev)
{
struct i3c_master_controller *master = i3c_dev_get_master(dev);
enum i3c_addr_slot_status status;
if (!dev->info.static_addr && !dev->info.dyn_addr)
return 0;
if (dev->info.static_addr) {
status = i3c_bus_get_addr_slot_status(&master->bus,
dev->info.static_addr);
if (status != I3C_ADDR_SLOT_FREE)
return -EBUSY;
i3c_bus_set_addr_slot_status(&master->bus,
dev->info.static_addr,
I3C_ADDR_SLOT_I3C_DEV);
}
/*
* ->init_dyn_addr should have been reserved before that, so, if we're
* trying to apply a pre-reserved dynamic address, we should not try
* to reserve the address slot a second time.
*/
if (dev->info.dyn_addr &&
(!dev->boardinfo ||
dev->boardinfo->init_dyn_addr != dev->info.dyn_addr)) {
status = i3c_bus_get_addr_slot_status(&master->bus,
dev->info.dyn_addr);
if (status != I3C_ADDR_SLOT_FREE)
goto err_release_static_addr;
i3c_bus_set_addr_slot_status(&master->bus, dev->info.dyn_addr,
I3C_ADDR_SLOT_I3C_DEV);
}
return 0;
err_release_static_addr:
if (dev->info.static_addr)
i3c_bus_set_addr_slot_status(&master->bus,
dev->info.static_addr,
I3C_ADDR_SLOT_FREE);
return -EBUSY;
}
static int i3c_master_attach_i3c_dev(struct i3c_master_controller *master,
struct i3c_dev_desc *dev)
{
int ret;
/*
* We don't attach devices to the controller until they are
* addressable on the bus.
*/
if (!dev->info.static_addr && !dev->info.dyn_addr)
return 0;
ret = i3c_master_get_i3c_addrs(dev);
if (ret)
return ret;
/* Do not attach the master device itself. */
if (master->this != dev && master->ops->attach_i3c_dev) {
ret = master->ops->attach_i3c_dev(dev);
if (ret) {
i3c_master_put_i3c_addrs(dev);
return ret;
}
}
list_add_tail(&dev->common.node, &master->bus.devs.i3c);
return 0;
}
static int i3c_master_reattach_i3c_dev(struct i3c_dev_desc *dev,
u8 old_dyn_addr)
{
struct i3c_master_controller *master = i3c_dev_get_master(dev);
enum i3c_addr_slot_status status;
int ret;
if (dev->info.dyn_addr != old_dyn_addr &&
(!dev->boardinfo ||
dev->info.dyn_addr != dev->boardinfo->init_dyn_addr)) {
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
status = i3c_bus_get_addr_slot_status(&master->bus,
dev->info.dyn_addr);
if (status != I3C_ADDR_SLOT_FREE)
return -EBUSY;
i3c_bus_set_addr_slot_status(&master->bus,
dev->info.dyn_addr,
I3C_ADDR_SLOT_I3C_DEV);
}
if (master->ops->reattach_i3c_dev) {
ret = master->ops->reattach_i3c_dev(dev, old_dyn_addr);
if (ret) {
i3c_master_put_i3c_addrs(dev);
return ret;
}
}
return 0;
}
static void i3c_master_detach_i3c_dev(struct i3c_dev_desc *dev)
{
struct i3c_master_controller *master = i3c_dev_get_master(dev);
/* Do not detach the master device itself. */
if (master->this != dev && master->ops->detach_i3c_dev)
master->ops->detach_i3c_dev(dev);
i3c_master_put_i3c_addrs(dev);
list_del(&dev->common.node);
}
static int i3c_master_attach_i2c_dev(struct i3c_master_controller *master,
struct i2c_dev_desc *dev)
{
int ret;
if (master->ops->attach_i2c_dev) {
ret = master->ops->attach_i2c_dev(dev);
if (ret)
return ret;
}
list_add_tail(&dev->common.node, &master->bus.devs.i2c);
return 0;
}
static void i3c_master_detach_i2c_dev(struct i2c_dev_desc *dev)
{
struct i3c_master_controller *master = i2c_dev_get_master(dev);
list_del(&dev->common.node);
if (master->ops->detach_i2c_dev)
master->ops->detach_i2c_dev(dev);
}
static int i3c_master_early_i3c_dev_add(struct i3c_master_controller *master,
struct i3c_dev_boardinfo *boardinfo)
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
{
struct i3c_device_info info = {
.static_addr = boardinfo->static_addr,
};
struct i3c_dev_desc *i3cdev;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
int ret;
i3cdev = i3c_master_alloc_i3c_dev(master, &info);
if (IS_ERR(i3cdev))
return -ENOMEM;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
i3cdev->boardinfo = boardinfo;
ret = i3c_master_attach_i3c_dev(master, i3cdev);
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
if (ret)
goto err_free_dev;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
ret = i3c_master_setdasa_locked(master, i3cdev->info.static_addr,
i3cdev->boardinfo->init_dyn_addr);
if (ret)
goto err_detach_dev;
i3cdev->info.dyn_addr = i3cdev->boardinfo->init_dyn_addr;
ret = i3c_master_reattach_i3c_dev(i3cdev, 0);
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
if (ret)
goto err_rstdaa;
ret = i3c_master_retrieve_dev_info(i3cdev);
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
if (ret)
goto err_rstdaa;
return 0;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
err_rstdaa:
i3c_master_rstdaa_locked(master, i3cdev->boardinfo->init_dyn_addr);
err_detach_dev:
i3c_master_detach_i3c_dev(i3cdev);
err_free_dev:
i3c_master_free_i3c_dev(i3cdev);
return ret;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
}
static void
i3c_master_register_new_i3c_devs(struct i3c_master_controller *master)
{
struct i3c_dev_desc *desc;
int ret;
if (!master->init_done)
return;
i3c_bus_for_each_i3cdev(&master->bus, desc) {
if (desc->dev || !desc->info.dyn_addr || desc == master->this)
continue;
desc->dev = kzalloc(sizeof(*desc->dev), GFP_KERNEL);
if (!desc->dev)
continue;
desc->dev->bus = &master->bus;
desc->dev->desc = desc;
desc->dev->dev.parent = &master->dev;
desc->dev->dev.type = &i3c_device_type;
desc->dev->dev.bus = &i3c_bus_type;
desc->dev->dev.release = i3c_device_release;
dev_set_name(&desc->dev->dev, "%d-%llx", master->bus.id,
desc->info.pid);
if (desc->boardinfo)
desc->dev->dev.of_node = desc->boardinfo->of_node;
ret = device_register(&desc->dev->dev);
if (ret)
dev_err(&master->dev,
"Failed to add I3C device (err = %d)\n", ret);
}
}
/**
* i3c_master_do_daa() - do a DAA (Dynamic Address Assignment)
* @master: master doing the DAA
*
* This function is instantiating an I3C device object and adding it to the
* I3C device list. All device information are automatically retrieved using
* standard CCC commands.
*
* The I3C device object is returned in case the master wants to attach
* private data to it using i3c_dev_set_master_data().
*
* This function must be called with the bus lock held in write mode.
*
* Return: a 0 in case of success, an negative error code otherwise.
*/
int i3c_master_do_daa(struct i3c_master_controller *master)
{
int ret;
i3c_bus_maintenance_lock(&master->bus);
ret = master->ops->do_daa(master);
i3c_bus_maintenance_unlock(&master->bus);
if (ret)
return ret;
i3c_bus_normaluse_lock(&master->bus);
i3c_master_register_new_i3c_devs(master);
i3c_bus_normaluse_unlock(&master->bus);
return 0;
}
EXPORT_SYMBOL_GPL(i3c_master_do_daa);
/**
* i3c_master_set_info() - set master device information
* @master: master used to send frames on the bus
* @info: I3C device information
*
* Set master device info. This should be called from
* &i3c_master_controller_ops->bus_init().
*
* Not all &i3c_device_info fields are meaningful for a master device.
* Here is a list of fields that should be properly filled:
*
* - &i3c_device_info->dyn_addr
* - &i3c_device_info->bcr
* - &i3c_device_info->dcr
* - &i3c_device_info->pid
* - &i3c_device_info->hdr_cap if %I3C_BCR_HDR_CAP bit is set in
* &i3c_device_info->bcr
*
* This function must be called with the bus lock held in maintenance mode.
*
* Return: 0 if @info contains valid information (not every piece of
* information can be checked, but we can at least make sure @info->dyn_addr
* and @info->bcr are correct), -EINVAL otherwise.
*/
int i3c_master_set_info(struct i3c_master_controller *master,
const struct i3c_device_info *info)
{
struct i3c_dev_desc *i3cdev;
int ret;
if (!i3c_bus_dev_addr_is_avail(&master->bus, info->dyn_addr))
return -EINVAL;
if (I3C_BCR_DEVICE_ROLE(info->bcr) == I3C_BCR_I3C_MASTER &&
master->secondary)
return -EINVAL;
if (master->this)
return -EINVAL;
i3cdev = i3c_master_alloc_i3c_dev(master, info);
if (IS_ERR(i3cdev))
return PTR_ERR(i3cdev);
master->this = i3cdev;
master->bus.cur_master = master->this;
ret = i3c_master_attach_i3c_dev(master, i3cdev);
if (ret)
goto err_free_dev;
return 0;
err_free_dev:
i3c_master_free_i3c_dev(i3cdev);
return ret;
}
EXPORT_SYMBOL_GPL(i3c_master_set_info);
static void i3c_master_detach_free_devs(struct i3c_master_controller *master)
{
struct i3c_dev_desc *i3cdev, *i3ctmp;
struct i2c_dev_desc *i2cdev, *i2ctmp;
list_for_each_entry_safe(i3cdev, i3ctmp, &master->bus.devs.i3c,
common.node) {
i3c_master_detach_i3c_dev(i3cdev);
if (i3cdev->boardinfo && i3cdev->boardinfo->init_dyn_addr)
i3c_bus_set_addr_slot_status(&master->bus,
i3cdev->boardinfo->init_dyn_addr,
I3C_ADDR_SLOT_FREE);
i3c_master_free_i3c_dev(i3cdev);
}
list_for_each_entry_safe(i2cdev, i2ctmp, &master->bus.devs.i2c,
common.node) {
i3c_master_detach_i2c_dev(i2cdev);
i3c_bus_set_addr_slot_status(&master->bus,
i2cdev->addr,
I3C_ADDR_SLOT_FREE);
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
i3c_master_free_i2c_dev(i2cdev);
}
}
/**
* i3c_master_bus_init() - initialize an I3C bus
* @master: main master initializing the bus
*
* This function is following all initialisation steps described in the I3C
* specification:
*
* 1. Attach I2C devs to the master so that the master can fill its internal
* device table appropriately
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
*
* 2. Call &i3c_master_controller_ops->bus_init() method to initialize
* the master controller. That's usually where the bus mode is selected
* (pure bus or mixed fast/slow bus)
*
* 3. Instruct all devices on the bus to drop their dynamic address. This is
* particularly important when the bus was previously configured by someone
* else (for example the bootloader)
*
* 4. Disable all slave events.
*
* 5. Reserve address slots for I3C devices with init_dyn_addr. And if devices
* also have static_addr, try to pre-assign dynamic addresses requested by
* the FW with SETDASA and attach corresponding statically defined I3C
* devices to the master.
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
*
* 6. Do a DAA (Dynamic Address Assignment) to assign dynamic addresses to all
* remaining I3C devices
*
* Once this is done, all I3C and I2C devices should be usable.
*
* Return: a 0 in case of success, an negative error code otherwise.
*/
static int i3c_master_bus_init(struct i3c_master_controller *master)
{
enum i3c_addr_slot_status status;
struct i2c_dev_boardinfo *i2cboardinfo;
struct i3c_dev_boardinfo *i3cboardinfo;
struct i2c_dev_desc *i2cdev;
int ret;
/*
* First attach all devices with static definitions provided by the
* FW.
*/
list_for_each_entry(i2cboardinfo, &master->boardinfo.i2c, node) {
status = i3c_bus_get_addr_slot_status(&master->bus,
i2cboardinfo->base.addr);
if (status != I3C_ADDR_SLOT_FREE) {
ret = -EBUSY;
goto err_detach_devs;
}
i3c_bus_set_addr_slot_status(&master->bus,
i2cboardinfo->base.addr,
I3C_ADDR_SLOT_I2C_DEV);
i2cdev = i3c_master_alloc_i2c_dev(master,
i2cboardinfo->base.addr,
i2cboardinfo->lvr);
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
if (IS_ERR(i2cdev)) {
ret = PTR_ERR(i2cdev);
goto err_detach_devs;
}
ret = i3c_master_attach_i2c_dev(master, i2cdev);
if (ret) {
i3c_master_free_i2c_dev(i2cdev);
goto err_detach_devs;
}
}
/*
* Now execute the controller specific ->bus_init() routine, which
* might configure its internal logic to match the bus limitations.
*/
ret = master->ops->bus_init(master);
if (ret)
goto err_detach_devs;
/*
* The master device should have been instantiated in ->bus_init(),
* complain if this was not the case.
*/
if (!master->this) {
dev_err(&master->dev,
"master_set_info() was not called in ->bus_init()\n");
ret = -EINVAL;
goto err_bus_cleanup;
}
/*
* Reset all dynamic address that may have been assigned before
* (assigned by the bootloader for example).
*/
ret = i3c_master_rstdaa_locked(master, I3C_BROADCAST_ADDR);
if (ret && ret != I3C_ERROR_M2)
goto err_bus_cleanup;
/* Disable all slave events before starting DAA. */
ret = i3c_master_disec_locked(master, I3C_BROADCAST_ADDR,
I3C_CCC_EVENT_SIR | I3C_CCC_EVENT_MR |
I3C_CCC_EVENT_HJ);
if (ret && ret != I3C_ERROR_M2)
goto err_bus_cleanup;
/*
* Reserve init_dyn_addr first, and then try to pre-assign dynamic
* address and retrieve device information if needed.
* In case pre-assign dynamic address fails, setting dynamic address to
* the requested init_dyn_addr is retried after DAA is done in
* i3c_master_add_i3c_dev_locked().
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
*/
list_for_each_entry(i3cboardinfo, &master->boardinfo.i3c, node) {
/*
* We don't reserve a dynamic address for devices that
* don't explicitly request one.
*/
if (!i3cboardinfo->init_dyn_addr)
continue;
ret = i3c_bus_get_addr_slot_status(&master->bus,
i3cboardinfo->init_dyn_addr);
if (ret != I3C_ADDR_SLOT_FREE) {
ret = -EBUSY;
goto err_rstdaa;
}
i3c_bus_set_addr_slot_status(&master->bus,
i3cboardinfo->init_dyn_addr,
I3C_ADDR_SLOT_I3C_DEV);
/*
* Only try to create/attach devices that have a static
* address. Other devices will be created/attached when
* DAA happens, and the requested dynamic address will
* be set using SETNEWDA once those devices become
* addressable.
*/
if (i3cboardinfo->static_addr)
i3c_master_early_i3c_dev_add(master, i3cboardinfo);
}
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
ret = i3c_master_do_daa(master);
if (ret)
goto err_rstdaa;
return 0;
err_rstdaa:
i3c_master_rstdaa_locked(master, I3C_BROADCAST_ADDR);
err_bus_cleanup:
if (master->ops->bus_cleanup)
master->ops->bus_cleanup(master);
err_detach_devs:
i3c_master_detach_free_devs(master);
return ret;
}
static void i3c_master_bus_cleanup(struct i3c_master_controller *master)
{
if (master->ops->bus_cleanup)
master->ops->bus_cleanup(master);
i3c_master_detach_free_devs(master);
}
static void i3c_master_attach_boardinfo(struct i3c_dev_desc *i3cdev)
{
struct i3c_master_controller *master = i3cdev->common.master;
struct i3c_dev_boardinfo *i3cboardinfo;
list_for_each_entry(i3cboardinfo, &master->boardinfo.i3c, node) {
if (i3cdev->info.pid != i3cboardinfo->pid)
continue;
i3cdev->boardinfo = i3cboardinfo;
i3cdev->info.static_addr = i3cboardinfo->static_addr;
return;
}
}
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
static struct i3c_dev_desc *
i3c_master_search_i3c_dev_duplicate(struct i3c_dev_desc *refdev)
{
struct i3c_master_controller *master = i3c_dev_get_master(refdev);
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
struct i3c_dev_desc *i3cdev;
i3c_bus_for_each_i3cdev(&master->bus, i3cdev) {
if (i3cdev != refdev && i3cdev->info.pid == refdev->info.pid)
return i3cdev;
}
return NULL;
}
/**
* i3c_master_add_i3c_dev_locked() - add an I3C slave to the bus
* @master: master used to send frames on the bus
* @addr: I3C slave dynamic address assigned to the device
*
* This function is instantiating an I3C device object and adding it to the
* I3C device list. All device information are automatically retrieved using
* standard CCC commands.
*
* The I3C device object is returned in case the master wants to attach
* private data to it using i3c_dev_set_master_data().
*
* This function must be called with the bus lock held in write mode.
*
* Return: a 0 in case of success, an negative error code otherwise.
*/
int i3c_master_add_i3c_dev_locked(struct i3c_master_controller *master,
u8 addr)
{
struct i3c_device_info info = { .dyn_addr = addr };
struct i3c_dev_desc *newdev, *olddev;
u8 old_dyn_addr = addr, expected_dyn_addr;
struct i3c_ibi_setup ibireq = { };
bool enable_ibi = false;
int ret;
if (!master)
return -EINVAL;
newdev = i3c_master_alloc_i3c_dev(master, &info);
if (IS_ERR(newdev))
return PTR_ERR(newdev);
ret = i3c_master_attach_i3c_dev(master, newdev);
if (ret)
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
goto err_free_dev;
ret = i3c_master_retrieve_dev_info(newdev);
if (ret)
goto err_detach_dev;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
i3c_master_attach_boardinfo(newdev);
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
olddev = i3c_master_search_i3c_dev_duplicate(newdev);
if (olddev) {
newdev->dev = olddev->dev;
if (newdev->dev)
newdev->dev->desc = newdev;
/*
* We need to restore the IBI state too, so let's save the
* IBI information and try to restore them after olddev has
* been detached+released and its IBI has been stopped and
* the associated resources have been freed.
*/
mutex_lock(&olddev->ibi_lock);
if (olddev->ibi) {
ibireq.handler = olddev->ibi->handler;
ibireq.max_payload_len = olddev->ibi->max_payload_len;
ibireq.num_slots = olddev->ibi->num_slots;
if (olddev->ibi->enabled) {
enable_ibi = true;
i3c_dev_disable_ibi_locked(olddev);
}
i3c_dev_free_ibi_locked(olddev);
}
mutex_unlock(&olddev->ibi_lock);
old_dyn_addr = olddev->info.dyn_addr;
i3c_master_detach_i3c_dev(olddev);
i3c_master_free_i3c_dev(olddev);
}
ret = i3c_master_reattach_i3c_dev(newdev, old_dyn_addr);
if (ret)
goto err_detach_dev;
/*
* Depending on our previous state, the expected dynamic address might
* differ:
* - if the device already had a dynamic address assigned, let's try to
* re-apply this one
* - if the device did not have a dynamic address and the firmware
* requested a specific address, pick this one
* - in any other case, keep the address automatically assigned by the
* master
*/
if (old_dyn_addr && old_dyn_addr != newdev->info.dyn_addr)
expected_dyn_addr = old_dyn_addr;
else if (newdev->boardinfo && newdev->boardinfo->init_dyn_addr)
expected_dyn_addr = newdev->boardinfo->init_dyn_addr;
else
expected_dyn_addr = newdev->info.dyn_addr;
if (newdev->info.dyn_addr != expected_dyn_addr) {
/*
* Try to apply the expected dynamic address. If it fails, keep
* the address assigned by the master.
*/
ret = i3c_master_setnewda_locked(master,
newdev->info.dyn_addr,
expected_dyn_addr);
if (!ret) {
old_dyn_addr = newdev->info.dyn_addr;
newdev->info.dyn_addr = expected_dyn_addr;
i3c_master_reattach_i3c_dev(newdev, old_dyn_addr);
} else {
dev_err(&master->dev,
"Failed to assign reserved/old address to device %d%llx",
master->bus.id, newdev->info.pid);
}
}
/*
* Now is time to try to restore the IBI setup. If we're lucky,
* everything works as before, otherwise, all we can do is complain.
* FIXME: maybe we should add callback to inform the driver that it
* should request the IBI again instead of trying to hide that from
* him.
*/
if (ibireq.handler) {
mutex_lock(&newdev->ibi_lock);
ret = i3c_dev_request_ibi_locked(newdev, &ibireq);
if (ret) {
dev_err(&master->dev,
"Failed to request IBI on device %d-%llx",
master->bus.id, newdev->info.pid);
} else if (enable_ibi) {
ret = i3c_dev_enable_ibi_locked(newdev);
if (ret)
dev_err(&master->dev,
"Failed to re-enable IBI on device %d-%llx",
master->bus.id, newdev->info.pid);
}
mutex_unlock(&newdev->ibi_lock);
}
return 0;
err_detach_dev:
if (newdev->dev && newdev->dev->desc)
newdev->dev->desc = NULL;
i3c_master_detach_i3c_dev(newdev);
err_free_dev:
i3c_master_free_i3c_dev(newdev);
return ret;
}
EXPORT_SYMBOL_GPL(i3c_master_add_i3c_dev_locked);
#define OF_I3C_REG1_IS_I2C_DEV BIT(31)
static int
of_i3c_master_add_i2c_boardinfo(struct i3c_master_controller *master,
struct device_node *node, u32 *reg)
{
struct i2c_dev_boardinfo *boardinfo;
struct device *dev = &master->dev;
int ret;
boardinfo = devm_kzalloc(dev, sizeof(*boardinfo), GFP_KERNEL);
if (!boardinfo)
return -ENOMEM;
ret = of_i2c_get_board_info(dev, node, &boardinfo->base);
if (ret)
return ret;
/*
* The I3C Specification does not clearly say I2C devices with 10-bit
* address are supported. These devices can't be passed properly through
* DEFSLVS command.
*/
if (boardinfo->base.flags & I2C_CLIENT_TEN) {
dev_err(dev, "I2C device with 10 bit address not supported.");
return -ENOTSUPP;
}
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
/* LVR is encoded in reg[2]. */
boardinfo->lvr = reg[2];
list_add_tail(&boardinfo->node, &master->boardinfo.i2c);
of_node_get(node);
return 0;
}
static int
of_i3c_master_add_i3c_boardinfo(struct i3c_master_controller *master,
struct device_node *node, u32 *reg)
{
struct i3c_dev_boardinfo *boardinfo;
struct device *dev = &master->dev;
enum i3c_addr_slot_status addrstatus;
u32 init_dyn_addr = 0;
boardinfo = devm_kzalloc(dev, sizeof(*boardinfo), GFP_KERNEL);
if (!boardinfo)
return -ENOMEM;
if (reg[0]) {
if (reg[0] > I3C_MAX_ADDR)
return -EINVAL;
addrstatus = i3c_bus_get_addr_slot_status(&master->bus,
reg[0]);
if (addrstatus != I3C_ADDR_SLOT_FREE)
return -EINVAL;
}
boardinfo->static_addr = reg[0];
if (!of_property_read_u32(node, "assigned-address", &init_dyn_addr)) {
if (init_dyn_addr > I3C_MAX_ADDR)
return -EINVAL;
addrstatus = i3c_bus_get_addr_slot_status(&master->bus,
init_dyn_addr);
if (addrstatus != I3C_ADDR_SLOT_FREE)
return -EINVAL;
}
boardinfo->pid = ((u64)reg[1] << 32) | reg[2];
if ((boardinfo->pid & GENMASK_ULL(63, 48)) ||
I3C_PID_RND_LOWER_32BITS(boardinfo->pid))
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
return -EINVAL;
boardinfo->init_dyn_addr = init_dyn_addr;
boardinfo->of_node = of_node_get(node);
list_add_tail(&boardinfo->node, &master->boardinfo.i3c);
return 0;
}
static int of_i3c_master_add_dev(struct i3c_master_controller *master,
struct device_node *node)
{
u32 reg[3];
int ret;
if (!master || !node)
return -EINVAL;
ret = of_property_read_u32_array(node, "reg", reg, ARRAY_SIZE(reg));
if (ret)
return ret;
/*
* The manufacturer ID can't be 0. If reg[1] == 0 that means we're
* dealing with an I2C device.
*/
if (!reg[1])
ret = of_i3c_master_add_i2c_boardinfo(master, node, reg);
else
ret = of_i3c_master_add_i3c_boardinfo(master, node, reg);
return ret;
}
static int of_populate_i3c_bus(struct i3c_master_controller *master)
{
struct device *dev = &master->dev;
struct device_node *i3cbus_np = dev->of_node;
struct device_node *node;
int ret;
u32 val;
if (!i3cbus_np)
return 0;
for_each_available_child_of_node(i3cbus_np, node) {
ret = of_i3c_master_add_dev(master, node);
if (ret) {
of_node_put(node);
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
return ret;
}
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
}
/*
* The user might want to limit I2C and I3C speed in case some devices
* on the bus are not supporting typical rates, or if the bus topology
* prevents it from using max possible rate.
*/
if (!of_property_read_u32(i3cbus_np, "i2c-scl-hz", &val))
master->bus.scl_rate.i2c = val;
if (!of_property_read_u32(i3cbus_np, "i3c-scl-hz", &val))
master->bus.scl_rate.i3c = val;
return 0;
}
static int i3c_master_i2c_adapter_xfer(struct i2c_adapter *adap,
struct i2c_msg *xfers, int nxfers)
{
struct i3c_master_controller *master = i2c_adapter_to_i3c_master(adap);
struct i2c_dev_desc *dev;
int i, ret;
u16 addr;
if (!xfers || !master || nxfers <= 0)
return -EINVAL;
if (!master->ops->i2c_xfers)
return -ENOTSUPP;
/* Doing transfers to different devices is not supported. */
addr = xfers[0].addr;
for (i = 1; i < nxfers; i++) {
if (addr != xfers[i].addr)
return -ENOTSUPP;
}
i3c_bus_normaluse_lock(&master->bus);
dev = i3c_master_find_i2c_dev_by_addr(master, addr);
if (!dev)
ret = -ENOENT;
else
ret = master->ops->i2c_xfers(dev, xfers, nxfers);
i3c_bus_normaluse_unlock(&master->bus);
return ret ? ret : nxfers;
}
static u32 i3c_master_i2c_funcs(struct i2c_adapter *adapter)
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
{
return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
}
static u8 i3c_master_i2c_get_lvr(struct i2c_client *client)
{
/* Fall back to no spike filters and FM bus mode. */
u8 lvr = I3C_LVR_I2C_INDEX(2) | I3C_LVR_I2C_FM_MODE;
if (client->dev.of_node) {
u32 reg[3];
if (!of_property_read_u32_array(client->dev.of_node, "reg",
reg, ARRAY_SIZE(reg)))
lvr = reg[2];
}
return lvr;
}
static int i3c_master_i2c_attach(struct i2c_adapter *adap, struct i2c_client *client)
{
struct i3c_master_controller *master = i2c_adapter_to_i3c_master(adap);
enum i3c_addr_slot_status status;
struct i2c_dev_desc *i2cdev;
int ret;
/* Already added by board info? */
if (i3c_master_find_i2c_dev_by_addr(master, client->addr))
return 0;
status = i3c_bus_get_addr_slot_status(&master->bus, client->addr);
if (status != I3C_ADDR_SLOT_FREE)
return -EBUSY;
i3c_bus_set_addr_slot_status(&master->bus, client->addr,
I3C_ADDR_SLOT_I2C_DEV);
i2cdev = i3c_master_alloc_i2c_dev(master, client->addr,
i3c_master_i2c_get_lvr(client));
if (IS_ERR(i2cdev)) {
ret = PTR_ERR(i2cdev);
goto out_clear_status;
}
ret = i3c_master_attach_i2c_dev(master, i2cdev);
if (ret)
goto out_free_dev;
return 0;
out_free_dev:
i3c_master_free_i2c_dev(i2cdev);
out_clear_status:
i3c_bus_set_addr_slot_status(&master->bus, client->addr,
I3C_ADDR_SLOT_FREE);
return ret;
}
static int i3c_master_i2c_detach(struct i2c_adapter *adap, struct i2c_client *client)
{
struct i3c_master_controller *master = i2c_adapter_to_i3c_master(adap);
struct i2c_dev_desc *dev;
dev = i3c_master_find_i2c_dev_by_addr(master, client->addr);
if (!dev)
return -ENODEV;
i3c_master_detach_i2c_dev(dev);
i3c_bus_set_addr_slot_status(&master->bus, dev->addr,
I3C_ADDR_SLOT_FREE);
i3c_master_free_i2c_dev(dev);
return 0;
}
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
static const struct i2c_algorithm i3c_master_i2c_algo = {
.master_xfer = i3c_master_i2c_adapter_xfer,
.functionality = i3c_master_i2c_funcs,
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
};
static int i3c_i2c_notifier_call(struct notifier_block *nb, unsigned long action,
void *data)
{
struct i2c_adapter *adap;
struct i2c_client *client;
struct device *dev = data;
struct i3c_master_controller *master;
int ret;
if (dev->type != &i2c_client_type)
return 0;
client = to_i2c_client(dev);
adap = client->adapter;
if (adap->algo != &i3c_master_i2c_algo)
return 0;
master = i2c_adapter_to_i3c_master(adap);
i3c_bus_maintenance_lock(&master->bus);
switch (action) {
case BUS_NOTIFY_ADD_DEVICE:
ret = i3c_master_i2c_attach(adap, client);
break;
case BUS_NOTIFY_DEL_DEVICE:
ret = i3c_master_i2c_detach(adap, client);
break;
}
i3c_bus_maintenance_unlock(&master->bus);
return ret;
}
static struct notifier_block i2cdev_notifier = {
.notifier_call = i3c_i2c_notifier_call,
};
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
static int i3c_master_i2c_adapter_init(struct i3c_master_controller *master)
{
struct i2c_adapter *adap = i3c_master_to_i2c_adapter(master);
struct i2c_dev_desc *i2cdev;
struct i2c_dev_boardinfo *i2cboardinfo;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
int ret;
adap->dev.parent = master->dev.parent;
adap->owner = master->dev.parent->driver->owner;
adap->algo = &i3c_master_i2c_algo;
strncpy(adap->name, dev_name(master->dev.parent), sizeof(adap->name));
/* FIXME: Should we allow i3c masters to override these values? */
adap->timeout = 1000;
adap->retries = 3;
ret = i2c_add_adapter(adap);
if (ret)
return ret;
/*
* We silently ignore failures here. The bus should keep working
* correctly even if one or more i2c devices are not registered.
*/
list_for_each_entry(i2cboardinfo, &master->boardinfo.i2c, node) {
i2cdev = i3c_master_find_i2c_dev_by_addr(master,
i2cboardinfo->base.addr);
if (WARN_ON(!i2cdev))
continue;
i2cdev->dev = i2c_new_client_device(adap, &i2cboardinfo->base);
}
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
return 0;
}
static void i3c_master_i2c_adapter_cleanup(struct i3c_master_controller *master)
{
struct i2c_dev_desc *i2cdev;
i2c_del_adapter(&master->i2c);
i3c_bus_for_each_i2cdev(&master->bus, i2cdev)
i2cdev->dev = NULL;
}
static void i3c_master_unregister_i3c_devs(struct i3c_master_controller *master)
{
struct i3c_dev_desc *i3cdev;
i3c_bus_for_each_i3cdev(&master->bus, i3cdev) {
if (!i3cdev->dev)
continue;
i3cdev->dev->desc = NULL;
if (device_is_registered(&i3cdev->dev->dev))
device_unregister(&i3cdev->dev->dev);
else
put_device(&i3cdev->dev->dev);
i3cdev->dev = NULL;
}
}
/**
* i3c_master_queue_ibi() - Queue an IBI
* @dev: the device this IBI is coming from
* @slot: the IBI slot used to store the payload
*
* Queue an IBI to the controller workqueue. The IBI handler attached to
* the dev will be called from a workqueue context.
*/
void i3c_master_queue_ibi(struct i3c_dev_desc *dev, struct i3c_ibi_slot *slot)
{
atomic_inc(&dev->ibi->pending_ibis);
queue_work(dev->common.master->wq, &slot->work);
}
EXPORT_SYMBOL_GPL(i3c_master_queue_ibi);
static void i3c_master_handle_ibi(struct work_struct *work)
{
struct i3c_ibi_slot *slot = container_of(work, struct i3c_ibi_slot,
work);
struct i3c_dev_desc *dev = slot->dev;
struct i3c_master_controller *master = i3c_dev_get_master(dev);
struct i3c_ibi_payload payload;
payload.data = slot->data;
payload.len = slot->len;
if (dev->dev)
dev->ibi->handler(dev->dev, &payload);
master->ops->recycle_ibi_slot(dev, slot);
if (atomic_dec_and_test(&dev->ibi->pending_ibis))
complete(&dev->ibi->all_ibis_handled);
}
static void i3c_master_init_ibi_slot(struct i3c_dev_desc *dev,
struct i3c_ibi_slot *slot)
{
slot->dev = dev;
INIT_WORK(&slot->work, i3c_master_handle_ibi);
}
struct i3c_generic_ibi_slot {
struct list_head node;
struct i3c_ibi_slot base;
};
struct i3c_generic_ibi_pool {
spinlock_t lock;
unsigned int num_slots;
struct i3c_generic_ibi_slot *slots;
void *payload_buf;
struct list_head free_slots;
struct list_head pending;
};
/**
* i3c_generic_ibi_free_pool() - Free a generic IBI pool
* @pool: the IBI pool to free
*
* Free all IBI slots allated by a generic IBI pool.
*/
void i3c_generic_ibi_free_pool(struct i3c_generic_ibi_pool *pool)
{
struct i3c_generic_ibi_slot *slot;
unsigned int nslots = 0;
while (!list_empty(&pool->free_slots)) {
slot = list_first_entry(&pool->free_slots,
struct i3c_generic_ibi_slot, node);
list_del(&slot->node);
nslots++;
}
/*
* If the number of freed slots is not equal to the number of allocated
* slots we have a leak somewhere.
*/
WARN_ON(nslots != pool->num_slots);
kfree(pool->payload_buf);
kfree(pool->slots);
kfree(pool);
}
EXPORT_SYMBOL_GPL(i3c_generic_ibi_free_pool);
/**
* i3c_generic_ibi_alloc_pool() - Create a generic IBI pool
* @dev: the device this pool will be used for
* @req: IBI setup request describing what the device driver expects
*
* Create a generic IBI pool based on the information provided in @req.
*
* Return: a valid IBI pool in case of success, an ERR_PTR() otherwise.
*/
struct i3c_generic_ibi_pool *
i3c_generic_ibi_alloc_pool(struct i3c_dev_desc *dev,
const struct i3c_ibi_setup *req)
{
struct i3c_generic_ibi_pool *pool;
struct i3c_generic_ibi_slot *slot;
unsigned int i;
int ret;
pool = kzalloc(sizeof(*pool), GFP_KERNEL);
if (!pool)
return ERR_PTR(-ENOMEM);
spin_lock_init(&pool->lock);
INIT_LIST_HEAD(&pool->free_slots);
INIT_LIST_HEAD(&pool->pending);
pool->slots = kcalloc(req->num_slots, sizeof(*slot), GFP_KERNEL);
if (!pool->slots) {
ret = -ENOMEM;
goto err_free_pool;
}
if (req->max_payload_len) {
pool->payload_buf = kcalloc(req->num_slots,
req->max_payload_len, GFP_KERNEL);
if (!pool->payload_buf) {
ret = -ENOMEM;
goto err_free_pool;
}
}
for (i = 0; i < req->num_slots; i++) {
slot = &pool->slots[i];
i3c_master_init_ibi_slot(dev, &slot->base);
if (req->max_payload_len)
slot->base.data = pool->payload_buf +
(i * req->max_payload_len);
list_add_tail(&slot->node, &pool->free_slots);
pool->num_slots++;
}
return pool;
err_free_pool:
i3c_generic_ibi_free_pool(pool);
return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(i3c_generic_ibi_alloc_pool);
/**
* i3c_generic_ibi_get_free_slot() - Get a free slot from a generic IBI pool
* @pool: the pool to query an IBI slot on
*
* Search for a free slot in a generic IBI pool.
* The slot should be returned to the pool using i3c_generic_ibi_recycle_slot()
* when it's no longer needed.
*
* Return: a pointer to a free slot, or NULL if there's no free slot available.
*/
struct i3c_ibi_slot *
i3c_generic_ibi_get_free_slot(struct i3c_generic_ibi_pool *pool)
{
struct i3c_generic_ibi_slot *slot;
unsigned long flags;
spin_lock_irqsave(&pool->lock, flags);
slot = list_first_entry_or_null(&pool->free_slots,
struct i3c_generic_ibi_slot, node);
if (slot)
list_del(&slot->node);
spin_unlock_irqrestore(&pool->lock, flags);
return slot ? &slot->base : NULL;
}
EXPORT_SYMBOL_GPL(i3c_generic_ibi_get_free_slot);
/**
* i3c_generic_ibi_recycle_slot() - Return a slot to a generic IBI pool
* @pool: the pool to return the IBI slot to
* @s: IBI slot to recycle
*
* Add an IBI slot back to its generic IBI pool. Should be called from the
* master driver struct_master_controller_ops->recycle_ibi() method.
*/
void i3c_generic_ibi_recycle_slot(struct i3c_generic_ibi_pool *pool,
struct i3c_ibi_slot *s)
{
struct i3c_generic_ibi_slot *slot;
unsigned long flags;
if (!s)
return;
slot = container_of(s, struct i3c_generic_ibi_slot, base);
spin_lock_irqsave(&pool->lock, flags);
list_add_tail(&slot->node, &pool->free_slots);
spin_unlock_irqrestore(&pool->lock, flags);
}
EXPORT_SYMBOL_GPL(i3c_generic_ibi_recycle_slot);
static int i3c_master_check_ops(const struct i3c_master_controller_ops *ops)
{
if (!ops || !ops->bus_init || !ops->priv_xfers ||
!ops->send_ccc_cmd || !ops->do_daa || !ops->i2c_xfers)
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
return -EINVAL;
if (ops->request_ibi &&
(!ops->enable_ibi || !ops->disable_ibi || !ops->free_ibi ||
!ops->recycle_ibi_slot))
return -EINVAL;
return 0;
}
/**
* i3c_master_register() - register an I3C master
* @master: master used to send frames on the bus
* @parent: the parent device (the one that provides this I3C master
* controller)
* @ops: the master controller operations
* @secondary: true if you are registering a secondary master. Will return
* -ENOTSUPP if set to true since secondary masters are not yet
* supported
*
* This function takes care of everything for you:
*
* - creates and initializes the I3C bus
* - populates the bus with static I2C devs if @parent->of_node is not
* NULL
* - registers all I3C devices added by the controller during bus
* initialization
* - registers the I2C adapter and all I2C devices
*
* Return: 0 in case of success, a negative error code otherwise.
*/
int i3c_master_register(struct i3c_master_controller *master,
struct device *parent,
const struct i3c_master_controller_ops *ops,
bool secondary)
{
unsigned long i2c_scl_rate = I3C_BUS_I2C_FM_PLUS_SCL_RATE;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
struct i3c_bus *i3cbus = i3c_master_get_bus(master);
enum i3c_bus_mode mode = I3C_BUS_MODE_PURE;
struct i2c_dev_boardinfo *i2cbi;
int ret;
/* We do not support secondary masters yet. */
if (secondary)
return -ENOTSUPP;
ret = i3c_master_check_ops(ops);
if (ret)
return ret;
master->dev.parent = parent;
master->dev.of_node = of_node_get(parent->of_node);
master->dev.bus = &i3c_bus_type;
master->dev.type = &i3c_masterdev_type;
master->dev.release = i3c_masterdev_release;
master->ops = ops;
master->secondary = secondary;
INIT_LIST_HEAD(&master->boardinfo.i2c);
INIT_LIST_HEAD(&master->boardinfo.i3c);
ret = i3c_bus_init(i3cbus);
if (ret)
return ret;
device_initialize(&master->dev);
dev_set_name(&master->dev, "i3c-%d", i3cbus->id);
ret = of_populate_i3c_bus(master);
if (ret)
goto err_put_dev;
list_for_each_entry(i2cbi, &master->boardinfo.i2c, node) {
switch (i2cbi->lvr & I3C_LVR_I2C_INDEX_MASK) {
case I3C_LVR_I2C_INDEX(0):
if (mode < I3C_BUS_MODE_MIXED_FAST)
mode = I3C_BUS_MODE_MIXED_FAST;
break;
case I3C_LVR_I2C_INDEX(1):
if (mode < I3C_BUS_MODE_MIXED_LIMITED)
mode = I3C_BUS_MODE_MIXED_LIMITED;
break;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
case I3C_LVR_I2C_INDEX(2):
if (mode < I3C_BUS_MODE_MIXED_SLOW)
mode = I3C_BUS_MODE_MIXED_SLOW;
break;
default:
ret = -EINVAL;
goto err_put_dev;
}
if (i2cbi->lvr & I3C_LVR_I2C_FM_MODE)
i2c_scl_rate = I3C_BUS_I2C_FM_SCL_RATE;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
}
ret = i3c_bus_set_mode(i3cbus, mode, i2c_scl_rate);
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
if (ret)
goto err_put_dev;
master->wq = alloc_workqueue("%s", 0, 0, dev_name(parent));
if (!master->wq) {
ret = -ENOMEM;
goto err_put_dev;
}
ret = i3c_master_bus_init(master);
if (ret)
Revert "i3c master: fix missing destroy_workqueue() on error in i3c_master_register" Adding the destroy_workqueue call in i3c_master_register introduced below kernel warning because it makes duplicate destroy_workqueue calls when i3c_master_register fails after allocating the workqueue. The workqueue will be destroyed by i3c_masterdev_release which is called by put_device at the end of the i3c_master_register function eventually in failure cases so the workqueue doesn't need to be destroyed in i3c_master_register. [ 6.972952] WARNING: CPU: 1 PID: 1 at lib/list_debug.c:48 __list_del_entry_valid+0x9c/0xf4 [ 6.982205] list_del corruption, 8fe03c08->prev is LIST_POISON2 (00000122) [ 6.989910] CPU: 1 PID: 1 Comm: swapper/0 Tainted: G W 5.10.23-c12838a-dirty-31dc772 #1 [ 7.000295] Hardware name: Generic DT based system [ 7.005638] Backtrace: [ 7.008369] [<809133f0>] (dump_backtrace) from [<80913644>] (show_stack+0x20/0x24) [ 7.016819] r7:00000030 r6:60000013 r5:00000000 r4:813b5d40 [ 7.023137] [<80913624>] (show_stack) from [<8091e1a0>] (dump_stack+0x9c/0xb0) [ 7.031201] [<8091e104>] (dump_stack) from [<8011fa30>] (__warn+0xf8/0x154) [ 7.038972] r7:00000030 r6:00000009 r5:804fa1c8 r4:80b6eca4 [ 7.045289] [<8011f938>] (__warn) from [<80913d14>] (warn_slowpath_fmt+0x8c/0xc0) [ 7.053641] r7:00000030 r6:80b6eca4 r5:80b6ed74 r4:818cc000 [ 7.059960] [<80913c8c>] (warn_slowpath_fmt) from [<804fa1c8>] (__list_del_entry_valid+0x9c/0xf4) [ 7.069866] r9:96becf8c r8:818cc000 r7:8fe03c10 r6:8fe03c00 r5:8fe03ba0 r4:ff7ead4c [ 7.078513] [<804fa12c>] (__list_del_entry_valid) from [<8013f0b4>] (destroy_workqueue+0x1c4/0x23c) [ 7.088615] [<8013eef0>] (destroy_workqueue) from [<806aa124>] (i3c_masterdev_release+0x40/0xb0) [ 7.098421] r7:00000000 r6:81a43b80 r5:8fe65360 r4:8fe65048 [ 7.104740] [<806aa0e4>] (i3c_masterdev_release) from [<805f3f04>] (device_release+0x40/0xb0) [ 7.114254] r5:00000000 r4:8fe65048 [ 7.118245] [<805f3ec4>] (device_release) from [<808fe754>] (kobject_put+0xc8/0x204) [ 7.126885] r5:813978dc r4:8fe65048 [ 7.130877] [<808fe68c>] (kobject_put) from [<805f5fbc>] (put_device+0x20/0x24) [ 7.139037] r7:8fe65358 r6:8fe65368 r5:8fe65358 r4:8fe65048 [ 7.145355] [<805f5f9c>] (put_device) from [<806abac4>] (i3c_master_register+0x338/0xb00) [ 7.154487] [<806ab78c>] (i3c_master_register) from [<806ae084>] (dw_i3c_probe+0x224/0x24c) [ 7.163811] r10:00000000 r9:8fe7a100 r8:00000032 r7:819fa810 r6:819fa800 r5:8fe65040 [ 7.172547] r4:00000000 [ 7.175376] [<806ade60>] (dw_i3c_probe) from [<805fdc14>] (platform_drv_probe+0x44/0x80) [ 7.184409] r9:813a25c0 r8:00000000 r7:815ec114 r6:00000000 r5:813a25c0 r4:819fa810 [ 7.193053] [<805fdbd0>] (platform_drv_probe) from [<805fb83c>] (really_probe+0x108/0x50c) [ 7.202275] r5:815ec004 r4:819fa810 [ 7.206265] [<805fb734>] (really_probe) from [<805fc180>] (driver_probe_device+0xb4/0x190) [ 7.215492] r10:813dc000 r9:80c4385c r8:000000d9 r7:813a25c0 r6:819fa810 r5:00000000 [ 7.224228] r4:813a25c0 [ 7.227055] [<805fc0cc>] (driver_probe_device) from [<805fc5cc>] (device_driver_attach+0xb8/0xc0) [ 7.236959] r9:80c4385c r8:000000d9 r7:813a25c0 r6:819fa854 r4:819fa810 [ 7.244439] [<805fc514>] (device_driver_attach) from [<805fc65c>] (__driver_attach+0x88/0x16c) [ 7.254051] r7:00000000 r6:819fa810 r5:00000000 r4:813a25c0 [ 7.260369] [<805fc5d4>] (__driver_attach) from [<805f954c>] (bus_for_each_dev+0x88/0xc8) [ 7.269489] r7:00000000 r6:818cc000 r5:805fc5d4 r4:813a25c0 [ 7.275806] [<805f94c4>] (bus_for_each_dev) from [<805fc76c>] (driver_attach+0x2c/0x30) [ 7.284739] r7:81397c98 r6:00000000 r5:8fe7db80 r4:813a25c0 [ 7.291057] [<805fc740>] (driver_attach) from [<805f9eec>] (bus_add_driver+0x120/0x200) [ 7.299984] [<805f9dcc>] (bus_add_driver) from [<805fce44>] (driver_register+0x98/0x128) [ 7.309005] r7:80c4383c r6:00000000 r5:00000000 r4:813a25c0 [ 7.315323] [<805fcdac>] (driver_register) from [<805fedb4>] (__platform_driver_register+0x50/0x58) [ 7.325410] r5:818cc000 r4:81397c98 [ 7.329404] [<805fed64>] (__platform_driver_register) from [<80c23398>] (dw_i3c_driver_init+0x24/0x28) [ 7.339790] r5:818cc000 r4:80c23374 [ 7.343784] [<80c23374>] (dw_i3c_driver_init) from [<80c01300>] (do_one_initcall+0xac/0x1d0) [ 7.353206] [<80c01254>] (do_one_initcall) from [<80c01630>] (kernel_init_freeable+0x1a8/0x204) [ 7.362916] r8:000000d9 r7:80c4383c r6:00000007 r5:819ca2c0 r4:80c67680 [ 7.370398] [<80c01488>] (kernel_init_freeable) from [<8091eb18>] (kernel_init+0x18/0x12c) [ 7.379616] r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:8091eb00 [ 7.388343] r4:00000000 [ 7.391170] [<8091eb00>] (kernel_init) from [<80100148>] (ret_from_fork+0x14/0x2c) [ 7.399607] Exception stack(0x818cdfb0 to 0x818cdff8) [ 7.405243] dfa0: 00000000 00000000 00000000 00000000 [ 7.414371] dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 7.423499] dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 [ 7.430879] r5:8091eb00 r4:00000000 This reverts commit 59165d16c699182b86b5c65181013f1fd88feb62. Fixes: 59165d16c699 ("i3c master: fix missing destroy_workqueue() on error in i3c_master_register") Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Link: https://lore.kernel.org/r/20210408172803.24599-1-jae.hyun.yoo@linux.intel.com
2021-04-09 01:28:03 +08:00
goto err_put_dev;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
ret = device_add(&master->dev);
if (ret)
goto err_cleanup_bus;
/*
* Expose our I3C bus as an I2C adapter so that I2C devices are exposed
* through the I2C subsystem.
*/
ret = i3c_master_i2c_adapter_init(master);
if (ret)
goto err_del_dev;
/*
* We're done initializing the bus and the controller, we can now
* register I3C devices discovered during the initial DAA.
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
*/
master->init_done = true;
i3c_bus_normaluse_lock(&master->bus);
i3c_master_register_new_i3c_devs(master);
i3c_bus_normaluse_unlock(&master->bus);
return 0;
err_del_dev:
device_del(&master->dev);
err_cleanup_bus:
i3c_master_bus_cleanup(master);
err_put_dev:
put_device(&master->dev);
return ret;
}
EXPORT_SYMBOL_GPL(i3c_master_register);
/**
* i3c_master_unregister() - unregister an I3C master
* @master: master used to send frames on the bus
*
* Basically undo everything done in i3c_master_register().
*
* Return: 0 in case of success, a negative error code otherwise.
*/
int i3c_master_unregister(struct i3c_master_controller *master)
{
i3c_master_i2c_adapter_cleanup(master);
i3c_master_unregister_i3c_devs(master);
i3c_master_bus_cleanup(master);
device_unregister(&master->dev);
return 0;
}
EXPORT_SYMBOL_GPL(i3c_master_unregister);
int i3c_dev_do_priv_xfers_locked(struct i3c_dev_desc *dev,
struct i3c_priv_xfer *xfers,
int nxfers)
{
struct i3c_master_controller *master;
if (!dev)
return -ENOENT;
master = i3c_dev_get_master(dev);
if (!master || !xfers)
return -EINVAL;
if (!master->ops->priv_xfers)
return -ENOTSUPP;
return master->ops->priv_xfers(dev, xfers, nxfers);
}
int i3c_dev_disable_ibi_locked(struct i3c_dev_desc *dev)
{
struct i3c_master_controller *master;
int ret;
if (!dev->ibi)
return -EINVAL;
master = i3c_dev_get_master(dev);
ret = master->ops->disable_ibi(dev);
if (ret)
return ret;
reinit_completion(&dev->ibi->all_ibis_handled);
if (atomic_read(&dev->ibi->pending_ibis))
wait_for_completion(&dev->ibi->all_ibis_handled);
dev->ibi->enabled = false;
return 0;
}
int i3c_dev_enable_ibi_locked(struct i3c_dev_desc *dev)
{
struct i3c_master_controller *master = i3c_dev_get_master(dev);
int ret;
if (!dev->ibi)
return -EINVAL;
ret = master->ops->enable_ibi(dev);
if (!ret)
dev->ibi->enabled = true;
return ret;
}
int i3c_dev_request_ibi_locked(struct i3c_dev_desc *dev,
const struct i3c_ibi_setup *req)
{
struct i3c_master_controller *master = i3c_dev_get_master(dev);
struct i3c_device_ibi_info *ibi;
int ret;
if (!master->ops->request_ibi)
return -ENOTSUPP;
if (dev->ibi)
return -EBUSY;
ibi = kzalloc(sizeof(*ibi), GFP_KERNEL);
if (!ibi)
return -ENOMEM;
atomic_set(&ibi->pending_ibis, 0);
init_completion(&ibi->all_ibis_handled);
ibi->handler = req->handler;
ibi->max_payload_len = req->max_payload_len;
ibi->num_slots = req->num_slots;
dev->ibi = ibi;
ret = master->ops->request_ibi(dev, req);
if (ret) {
kfree(ibi);
dev->ibi = NULL;
}
return ret;
}
void i3c_dev_free_ibi_locked(struct i3c_dev_desc *dev)
{
struct i3c_master_controller *master = i3c_dev_get_master(dev);
if (!dev->ibi)
return;
if (WARN_ON(dev->ibi->enabled))
WARN_ON(i3c_dev_disable_ibi_locked(dev));
master->ops->free_ibi(dev);
kfree(dev->ibi);
dev->ibi = NULL;
}
static int __init i3c_init(void)
{
int res = bus_register_notifier(&i2c_bus_type, &i2cdev_notifier);
if (res)
return res;
res = bus_register(&i3c_bus_type);
if (res)
goto out_unreg_notifier;
return 0;
out_unreg_notifier:
bus_unregister_notifier(&i2c_bus_type, &i2cdev_notifier);
return res;
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
}
subsys_initcall(i3c_init);
static void __exit i3c_exit(void)
{
bus_unregister_notifier(&i2c_bus_type, &i2cdev_notifier);
i3c: Add core I3C infrastructure Add core infrastructure to support I3C in Linux and document it. This infrastructure adds basic I3C support. Advanced features will be added afterwards. There are a few design choices that are worth mentioning because they impact the way I3C device drivers can interact with their devices: - all functions used to send I3C/I2C frames must be called in non-atomic context. Mainly done this way to ease implementation, but this is not set in stone, and if anyone needs async support, new functions can be added later on. - the bus element is a separate object, but it's tightly coupled with the master object. We thus have a 1:1 relationship between i3c_bus and i3c_master_controller objects, and if 2 master controllers are connected to the same bus and both exposed to the same Linux instance they will appear as two distinct busses, and devices on this bus will be exposed twice. - I2C backward compatibility has been designed to be transparent to I2C drivers and the I2C subsystem. The I3C master just registers an I2C adapter which creates a new I2C bus. I'd say that, from a representation PoV it's not ideal because what should appear as a single I3C bus exposing I3C and I2C devices here appears as 2 different buses connected to each other through the parenting (the I3C master is the parent of the I2C and I3C busses). On the other hand, I don't see a better solution if we want something that is not invasive. Missing features: - I3C HDR modes are not supported - no support for multi-master and the associated concepts (mastership handover, support for secondary masters, ...) - I2C devices can only be described using DT because this is the only use case I have. However, the framework can easily be extended with ACPI and board info support - I3C slave framework. This has been completely omitted, but shouldn't have a huge impact on the I3C framework because I3C slaves don't see the whole bus, it's only about handling master requests and generating IBIs. Some of the struct, constant and enum definitions could be shared, but most of the I3C slave framework logic will be different Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-19 17:52:29 +08:00
idr_destroy(&i3c_bus_idr);
bus_unregister(&i3c_bus_type);
}
module_exit(i3c_exit);
MODULE_AUTHOR("Boris Brezillon <boris.brezillon@bootlin.com>");
MODULE_DESCRIPTION("I3C core");
MODULE_LICENSE("GPL v2");