Merge branch 'ib-gpio-aggregator' into devel
This commit is contained in:
Linus Walleij
commit
a0d50aa935
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@ -0,0 +1,111 @@
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.. SPDX-License-Identifier: GPL-2.0-only
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GPIO Aggregator
|
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===============
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||||
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The GPIO Aggregator provides a mechanism to aggregate GPIOs, and expose them as
|
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a new gpio_chip. This supports the following use cases.
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||||
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||||
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Aggregating GPIOs using Sysfs
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-----------------------------
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|
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GPIO controllers are exported to userspace using /dev/gpiochip* character
|
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devices. Access control to these devices is provided by standard UNIX file
|
||||
system permissions, on an all-or-nothing basis: either a GPIO controller is
|
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accessible for a user, or it is not.
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|
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The GPIO Aggregator provides access control for a set of one or more GPIOs, by
|
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aggregating them into a new gpio_chip, which can be assigned to a group or user
|
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using standard UNIX file ownership and permissions. Furthermore, this
|
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simplifies and hardens exporting GPIOs to a virtual machine, as the VM can just
|
||||
grab the full GPIO controller, and no longer needs to care about which GPIOs to
|
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grab and which not, reducing the attack surface.
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|
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Aggregated GPIO controllers are instantiated and destroyed by writing to
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write-only attribute files in sysfs.
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|
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/sys/bus/platform/drivers/gpio-aggregator/
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"new_device" ...
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Userspace may ask the kernel to instantiate an aggregated GPIO
|
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controller by writing a string describing the GPIOs to
|
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aggregate to the "new_device" file, using the format
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.. code-block:: none
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|
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[<gpioA>] [<gpiochipB> <offsets>] ...
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Where:
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||||
"<gpioA>" ...
|
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is a GPIO line name,
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||||
"<gpiochipB>" ...
|
||||
is a GPIO chip label, and
|
||||
|
||||
"<offsets>" ...
|
||||
is a comma-separated list of GPIO offsets and/or
|
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GPIO offset ranges denoted by dashes.
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|
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Example: Instantiate a new GPIO aggregator by aggregating GPIO
|
||||
line 19 of "e6052000.gpio" and GPIO lines 20-21 of
|
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"e6050000.gpio" into a new gpio_chip:
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|
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.. code-block:: sh
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|
||||
$ echo 'e6052000.gpio 19 e6050000.gpio 20-21' > new_device
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|
||||
"delete_device" ...
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Userspace may ask the kernel to destroy an aggregated GPIO
|
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controller after use by writing its device name to the
|
||||
"delete_device" file.
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|
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Example: Destroy the previously-created aggregated GPIO
|
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controller, assumed to be "gpio-aggregator.0":
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|
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.. code-block:: sh
|
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|
||||
$ echo gpio-aggregator.0 > delete_device
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|
||||
|
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Generic GPIO Driver
|
||||
-------------------
|
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|
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The GPIO Aggregator can also be used as a generic driver for a simple
|
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GPIO-operated device described in DT, without a dedicated in-kernel driver.
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This is useful in industrial control, and is not unlike e.g. spidev, which
|
||||
allows the user to communicate with an SPI device from userspace.
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|
||||
Binding a device to the GPIO Aggregator is performed either by modifying the
|
||||
gpio-aggregator driver, or by writing to the "driver_override" file in Sysfs.
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|
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Example: If "door" is a GPIO-operated device described in DT, using its own
|
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compatible value::
|
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|
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door {
|
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compatible = "myvendor,mydoor";
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gpios = <&gpio2 19 GPIO_ACTIVE_HIGH>,
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<&gpio2 20 GPIO_ACTIVE_LOW>;
|
||||
gpio-line-names = "open", "lock";
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||||
};
|
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|
||||
it can be bound to the GPIO Aggregator by either:
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||||
|
||||
1. Adding its compatible value to ``gpio_aggregator_dt_ids[]``,
|
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2. Binding manually using "driver_override":
|
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|
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.. code-block:: sh
|
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|
||||
$ echo gpio-aggregator > /sys/bus/platform/devices/door/driver_override
|
||||
$ echo door > /sys/bus/platform/drivers/gpio-aggregator/bind
|
||||
|
||||
After that, a new gpiochip "door" has been created:
|
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|
||||
.. code-block:: sh
|
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|
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$ gpioinfo door
|
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gpiochip12 - 2 lines:
|
||||
line 0: "open" unused input active-high
|
||||
line 1: "lock" unused input active-high
|
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|
|
@ -7,6 +7,7 @@ gpio
|
|||
.. toctree::
|
||||
:maxdepth: 1
|
||||
|
||||
gpio-aggregator
|
||||
sysfs
|
||||
|
||||
.. only:: subproject and html
|
||||
|
|
|
|||
|
|
@ -113,13 +113,15 @@ files that desire to do so need to include the following header::
|
|||
GPIOs are mapped by the means of tables of lookups, containing instances of the
|
||||
gpiod_lookup structure. Two macros are defined to help declaring such mappings::
|
||||
|
||||
GPIO_LOOKUP(chip_label, chip_hwnum, con_id, flags)
|
||||
GPIO_LOOKUP_IDX(chip_label, chip_hwnum, con_id, idx, flags)
|
||||
GPIO_LOOKUP(key, chip_hwnum, con_id, flags)
|
||||
GPIO_LOOKUP_IDX(key, chip_hwnum, con_id, idx, flags)
|
||||
|
||||
where
|
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|
||||
- chip_label is the label of the gpiod_chip instance providing the GPIO
|
||||
- chip_hwnum is the hardware number of the GPIO within the chip
|
||||
- key is either the label of the gpiod_chip instance providing the GPIO, or
|
||||
the GPIO line name
|
||||
- chip_hwnum is the hardware number of the GPIO within the chip, or U16_MAX
|
||||
to indicate that key is a GPIO line name
|
||||
- con_id is the name of the GPIO function from the device point of view. It
|
||||
can be NULL, in which case it will match any function.
|
||||
- idx is the index of the GPIO within the function.
|
||||
|
|
@ -135,7 +137,10 @@ where
|
|||
|
||||
In the future, these flags might be extended to support more properties.
|
||||
|
||||
Note that GPIO_LOOKUP() is just a shortcut to GPIO_LOOKUP_IDX() where idx = 0.
|
||||
Note that:
|
||||
1. GPIO line names are not guaranteed to be globally unique, so the first
|
||||
match found will be used.
|
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2. GPIO_LOOKUP() is just a shortcut to GPIO_LOOKUP_IDX() where idx = 0.
|
||||
|
||||
A lookup table can then be defined as follows, with an empty entry defining its
|
||||
end. The 'dev_id' field of the table is the identifier of the device that will
|
||||
|
|
|
|||
|
|
@ -7228,6 +7228,13 @@ F: Documentation/firmware-guide/acpi/gpio-properties.rst
|
|||
F: drivers/gpio/gpiolib-acpi.c
|
||||
F: drivers/gpio/gpiolib-acpi.h
|
||||
|
||||
GPIO AGGREGATOR
|
||||
M: Geert Uytterhoeven <geert+renesas@glider.be>
|
||||
L: linux-gpio@vger.kernel.org
|
||||
S: Supported
|
||||
F: Documentation/admin-guide/gpio/gpio-aggregator.rst
|
||||
F: drivers/gpio/gpio-aggregator.c
|
||||
|
||||
GPIO IR Transmitter
|
||||
M: Sean Young <sean@mess.org>
|
||||
L: linux-media@vger.kernel.org
|
||||
|
|
|
|||
|
|
@ -1541,6 +1541,18 @@ config GPIO_VIPERBOARD
|
|||
|
||||
endmenu
|
||||
|
||||
config GPIO_AGGREGATOR
|
||||
tristate "GPIO Aggregator"
|
||||
help
|
||||
Say yes here to enable the GPIO Aggregator, which provides a way to
|
||||
aggregate existing GPIO lines into a new virtual GPIO chip.
|
||||
This can serve the following purposes:
|
||||
- Assign permissions for a collection of GPIO lines to a user,
|
||||
- Export a collection of GPIO lines to a virtual machine,
|
||||
- Provide a generic driver for a GPIO-operated device in an
|
||||
industrial control context, to be operated from userspace using
|
||||
the GPIO chardev interface.
|
||||
|
||||
config GPIO_MOCKUP
|
||||
tristate "GPIO Testing Driver"
|
||||
select IRQ_SIM
|
||||
|
|
|
|||
|
|
@ -25,6 +25,7 @@ obj-$(CONFIG_GPIO_74XX_MMIO) += gpio-74xx-mmio.o
|
|||
obj-$(CONFIG_GPIO_ADNP) += gpio-adnp.o
|
||||
obj-$(CONFIG_GPIO_ADP5520) += gpio-adp5520.o
|
||||
obj-$(CONFIG_GPIO_ADP5588) += gpio-adp5588.o
|
||||
obj-$(CONFIG_GPIO_AGGREGATOR) += gpio-aggregator.o
|
||||
obj-$(CONFIG_GPIO_ALTERA_A10SR) += gpio-altera-a10sr.o
|
||||
obj-$(CONFIG_GPIO_ALTERA) += gpio-altera.o
|
||||
obj-$(CONFIG_GPIO_AMD8111) += gpio-amd8111.o
|
||||
|
|
|
|||
|
|
@ -0,0 +1,568 @@
|
|||
// SPDX-License-Identifier: GPL-2.0-only
|
||||
//
|
||||
// GPIO Aggregator
|
||||
//
|
||||
// Copyright (C) 2019-2020 Glider bv
|
||||
|
||||
#define DRV_NAME "gpio-aggregator"
|
||||
#define pr_fmt(fmt) DRV_NAME ": " fmt
|
||||
|
||||
#include <linux/bitmap.h>
|
||||
#include <linux/bitops.h>
|
||||
#include <linux/ctype.h>
|
||||
#include <linux/gpio/consumer.h>
|
||||
#include <linux/gpio/driver.h>
|
||||
#include <linux/gpio/machine.h>
|
||||
#include <linux/idr.h>
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/mutex.h>
|
||||
#include <linux/overflow.h>
|
||||
#include <linux/platform_device.h>
|
||||
#include <linux/spinlock.h>
|
||||
#include <linux/string.h>
|
||||
|
||||
|
||||
/*
|
||||
* GPIO Aggregator sysfs interface
|
||||
*/
|
||||
|
||||
struct gpio_aggregator {
|
||||
struct gpiod_lookup_table *lookups;
|
||||
struct platform_device *pdev;
|
||||
char args[];
|
||||
};
|
||||
|
||||
static DEFINE_MUTEX(gpio_aggregator_lock); /* protects idr */
|
||||
static DEFINE_IDR(gpio_aggregator_idr);
|
||||
|
||||
static char *get_arg(char **args)
|
||||
{
|
||||
char *start = *args, *end;
|
||||
|
||||
start = skip_spaces(start);
|
||||
if (!*start)
|
||||
return NULL;
|
||||
|
||||
if (*start == '"') {
|
||||
/* Quoted arg */
|
||||
end = strchr(++start, '"');
|
||||
if (!end)
|
||||
return ERR_PTR(-EINVAL);
|
||||
} else {
|
||||
/* Unquoted arg */
|
||||
for (end = start; *end && !isspace(*end); end++) ;
|
||||
}
|
||||
|
||||
if (*end)
|
||||
*end++ = '\0';
|
||||
|
||||
*args = end;
|
||||
return start;
|
||||
}
|
||||
|
||||
static bool isrange(const char *s)
|
||||
{
|
||||
size_t n;
|
||||
|
||||
if (IS_ERR_OR_NULL(s))
|
||||
return false;
|
||||
|
||||
while (1) {
|
||||
n = strspn(s, "0123456789");
|
||||
if (!n)
|
||||
return false;
|
||||
|
||||
s += n;
|
||||
|
||||
switch (*s++) {
|
||||
case '\0':
|
||||
return true;
|
||||
|
||||
case '-':
|
||||
case ',':
|
||||
break;
|
||||
|
||||
default:
|
||||
return false;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
static int aggr_add_gpio(struct gpio_aggregator *aggr, const char *key,
|
||||
int hwnum, unsigned int *n)
|
||||
{
|
||||
struct gpiod_lookup_table *lookups;
|
||||
|
||||
lookups = krealloc(aggr->lookups, struct_size(lookups, table, *n + 2),
|
||||
GFP_KERNEL);
|
||||
if (!lookups)
|
||||
return -ENOMEM;
|
||||
|
||||
lookups->table[*n] =
|
||||
(struct gpiod_lookup)GPIO_LOOKUP_IDX(key, hwnum, NULL, *n, 0);
|
||||
|
||||
(*n)++;
|
||||
memset(&lookups->table[*n], 0, sizeof(lookups->table[*n]));
|
||||
|
||||
aggr->lookups = lookups;
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int aggr_parse(struct gpio_aggregator *aggr)
|
||||
{
|
||||
unsigned int first_index, last_index, i, n = 0;
|
||||
char *name, *offsets, *first, *last, *next;
|
||||
char *args = aggr->args;
|
||||
int error;
|
||||
|
||||
for (name = get_arg(&args), offsets = get_arg(&args); name;
|
||||
offsets = get_arg(&args)) {
|
||||
if (IS_ERR(name)) {
|
||||
pr_err("Cannot get GPIO specifier: %pe\n", name);
|
||||
return PTR_ERR(name);
|
||||
}
|
||||
|
||||
if (!isrange(offsets)) {
|
||||
/* Named GPIO line */
|
||||
error = aggr_add_gpio(aggr, name, U16_MAX, &n);
|
||||
if (error)
|
||||
return error;
|
||||
|
||||
name = offsets;
|
||||
continue;
|
||||
}
|
||||
|
||||
/* GPIO chip + offset(s) */
|
||||
for (first = offsets; *first; first = next) {
|
||||
next = strchrnul(first, ',');
|
||||
if (*next)
|
||||
*next++ = '\0';
|
||||
|
||||
last = strchr(first, '-');
|
||||
if (last)
|
||||
*last++ = '\0';
|
||||
|
||||
if (kstrtouint(first, 10, &first_index)) {
|
||||
pr_err("Cannot parse GPIO index %s\n", first);
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
if (!last) {
|
||||
last_index = first_index;
|
||||
} else if (kstrtouint(last, 10, &last_index)) {
|
||||
pr_err("Cannot parse GPIO index %s\n", last);
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
for (i = first_index; i <= last_index; i++) {
|
||||
error = aggr_add_gpio(aggr, name, i, &n);
|
||||
if (error)
|
||||
return error;
|
||||
}
|
||||
}
|
||||
|
||||
name = get_arg(&args);
|
||||
}
|
||||
|
||||
if (!n) {
|
||||
pr_err("No GPIOs specified\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static ssize_t new_device_store(struct device_driver *driver, const char *buf,
|
||||
size_t count)
|
||||
{
|
||||
struct gpio_aggregator *aggr;
|
||||
struct platform_device *pdev;
|
||||
int res, id;
|
||||
|
||||
/* kernfs guarantees string termination, so count + 1 is safe */
|
||||
aggr = kzalloc(sizeof(*aggr) + count + 1, GFP_KERNEL);
|
||||
if (!aggr)
|
||||
return -ENOMEM;
|
||||
|
||||
memcpy(aggr->args, buf, count + 1);
|
||||
|
||||
aggr->lookups = kzalloc(struct_size(aggr->lookups, table, 1),
|
||||
GFP_KERNEL);
|
||||
if (!aggr->lookups) {
|
||||
res = -ENOMEM;
|
||||
goto free_ga;
|
||||
}
|
||||
|
||||
mutex_lock(&gpio_aggregator_lock);
|
||||
id = idr_alloc(&gpio_aggregator_idr, aggr, 0, 0, GFP_KERNEL);
|
||||
mutex_unlock(&gpio_aggregator_lock);
|
||||
|
||||
if (id < 0) {
|
||||
res = id;
|
||||
goto free_table;
|
||||
}
|
||||
|
||||
aggr->lookups->dev_id = kasprintf(GFP_KERNEL, "%s.%d", DRV_NAME, id);
|
||||
if (!aggr->lookups->dev_id) {
|
||||
res = -ENOMEM;
|
||||
goto remove_idr;
|
||||
}
|
||||
|
||||
res = aggr_parse(aggr);
|
||||
if (res)
|
||||
goto free_dev_id;
|
||||
|
||||
gpiod_add_lookup_table(aggr->lookups);
|
||||
|
||||
pdev = platform_device_register_simple(DRV_NAME, id, NULL, 0);
|
||||
if (IS_ERR(pdev)) {
|
||||
res = PTR_ERR(pdev);
|
||||
goto remove_table;
|
||||
}
|
||||
|
||||
aggr->pdev = pdev;
|
||||
return count;
|
||||
|
||||
remove_table:
|
||||
gpiod_remove_lookup_table(aggr->lookups);
|
||||
free_dev_id:
|
||||
kfree(aggr->lookups->dev_id);
|
||||
remove_idr:
|
||||
mutex_lock(&gpio_aggregator_lock);
|
||||
idr_remove(&gpio_aggregator_idr, id);
|
||||
mutex_unlock(&gpio_aggregator_lock);
|
||||
free_table:
|
||||
kfree(aggr->lookups);
|
||||
free_ga:
|
||||
kfree(aggr);
|
||||
return res;
|
||||
}
|
||||
|
||||
static DRIVER_ATTR_WO(new_device);
|
||||
|
||||
static void gpio_aggregator_free(struct gpio_aggregator *aggr)
|
||||
{
|
||||
platform_device_unregister(aggr->pdev);
|
||||
gpiod_remove_lookup_table(aggr->lookups);
|
||||
kfree(aggr->lookups->dev_id);
|
||||
kfree(aggr->lookups);
|
||||
kfree(aggr);
|
||||
}
|
||||
|
||||
static ssize_t delete_device_store(struct device_driver *driver,
|
||||
const char *buf, size_t count)
|
||||
{
|
||||
struct gpio_aggregator *aggr;
|
||||
unsigned int id;
|
||||
int error;
|
||||
|
||||
if (!str_has_prefix(buf, DRV_NAME "."))
|
||||
return -EINVAL;
|
||||
|
||||
error = kstrtouint(buf + strlen(DRV_NAME "."), 10, &id);
|
||||
if (error)
|
||||
return error;
|
||||
|
||||
mutex_lock(&gpio_aggregator_lock);
|
||||
aggr = idr_remove(&gpio_aggregator_idr, id);
|
||||
mutex_unlock(&gpio_aggregator_lock);
|
||||
if (!aggr)
|
||||
return -ENOENT;
|
||||
|
||||
gpio_aggregator_free(aggr);
|
||||
return count;
|
||||
}
|
||||
static DRIVER_ATTR_WO(delete_device);
|
||||
|
||||
static struct attribute *gpio_aggregator_attrs[] = {
|
||||
&driver_attr_new_device.attr,
|
||||
&driver_attr_delete_device.attr,
|
||||
NULL,
|
||||
};
|
||||
ATTRIBUTE_GROUPS(gpio_aggregator);
|
||||
|
||||
static int __exit gpio_aggregator_idr_remove(int id, void *p, void *data)
|
||||
{
|
||||
gpio_aggregator_free(p);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void __exit gpio_aggregator_remove_all(void)
|
||||
{
|
||||
mutex_lock(&gpio_aggregator_lock);
|
||||
idr_for_each(&gpio_aggregator_idr, gpio_aggregator_idr_remove, NULL);
|
||||
idr_destroy(&gpio_aggregator_idr);
|
||||
mutex_unlock(&gpio_aggregator_lock);
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* GPIO Forwarder
|
||||
*/
|
||||
|
||||
struct gpiochip_fwd {
|
||||
struct gpio_chip chip;
|
||||
struct gpio_desc **descs;
|
||||
union {
|
||||
struct mutex mlock; /* protects tmp[] if can_sleep */
|
||||
spinlock_t slock; /* protects tmp[] if !can_sleep */
|
||||
};
|
||||
unsigned long tmp[]; /* values and descs for multiple ops */
|
||||
};
|
||||
|
||||
static int gpio_fwd_get_direction(struct gpio_chip *chip, unsigned int offset)
|
||||
{
|
||||
struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
|
||||
|
||||
return gpiod_get_direction(fwd->descs[offset]);
|
||||
}
|
||||
|
||||
static int gpio_fwd_direction_input(struct gpio_chip *chip, unsigned int offset)
|
||||
{
|
||||
struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
|
||||
|
||||
return gpiod_direction_input(fwd->descs[offset]);
|
||||
}
|
||||
|
||||
static int gpio_fwd_direction_output(struct gpio_chip *chip,
|
||||
unsigned int offset, int value)
|
||||
{
|
||||
struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
|
||||
|
||||
return gpiod_direction_output(fwd->descs[offset], value);
|
||||
}
|
||||
|
||||
static int gpio_fwd_get(struct gpio_chip *chip, unsigned int offset)
|
||||
{
|
||||
struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
|
||||
|
||||
return gpiod_get_value(fwd->descs[offset]);
|
||||
}
|
||||
|
||||
static int gpio_fwd_get_multiple(struct gpio_chip *chip, unsigned long *mask,
|
||||
unsigned long *bits)
|
||||
{
|
||||
struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
|
||||
unsigned long *values, flags = 0;
|
||||
struct gpio_desc **descs;
|
||||
unsigned int i, j = 0;
|
||||
int error;
|
||||
|
||||
if (chip->can_sleep)
|
||||
mutex_lock(&fwd->mlock);
|
||||
else
|
||||
spin_lock_irqsave(&fwd->slock, flags);
|
||||
|
||||
/* Both values bitmap and desc pointers are stored in tmp[] */
|
||||
values = &fwd->tmp[0];
|
||||
descs = (void *)&fwd->tmp[BITS_TO_LONGS(fwd->chip.ngpio)];
|
||||
|
||||
bitmap_clear(values, 0, fwd->chip.ngpio);
|
||||
for_each_set_bit(i, mask, fwd->chip.ngpio)
|
||||
descs[j++] = fwd->descs[i];
|
||||
|
||||
error = gpiod_get_array_value(j, descs, NULL, values);
|
||||
if (!error) {
|
||||
j = 0;
|
||||
for_each_set_bit(i, mask, fwd->chip.ngpio)
|
||||
__assign_bit(i, bits, test_bit(j++, values));
|
||||
}
|
||||
|
||||
if (chip->can_sleep)
|
||||
mutex_unlock(&fwd->mlock);
|
||||
else
|
||||
spin_unlock_irqrestore(&fwd->slock, flags);
|
||||
|
||||
return error;
|
||||
}
|
||||
|
||||
static void gpio_fwd_set(struct gpio_chip *chip, unsigned int offset, int value)
|
||||
{
|
||||
struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
|
||||
|
||||
gpiod_set_value(fwd->descs[offset], value);
|
||||
}
|
||||
|
||||
static void gpio_fwd_set_multiple(struct gpio_chip *chip, unsigned long *mask,
|
||||
unsigned long *bits)
|
||||
{
|
||||
struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
|
||||
unsigned long *values, flags = 0;
|
||||
struct gpio_desc **descs;
|
||||
unsigned int i, j = 0;
|
||||
|
||||
if (chip->can_sleep)
|
||||
mutex_lock(&fwd->mlock);
|
||||
else
|
||||
spin_lock_irqsave(&fwd->slock, flags);
|
||||
|
||||
/* Both values bitmap and desc pointers are stored in tmp[] */
|
||||
values = &fwd->tmp[0];
|
||||
descs = (void *)&fwd->tmp[BITS_TO_LONGS(fwd->chip.ngpio)];
|
||||
|
||||
for_each_set_bit(i, mask, fwd->chip.ngpio) {
|
||||
__assign_bit(j, values, test_bit(i, bits));
|
||||
descs[j++] = fwd->descs[i];
|
||||
}
|
||||
|
||||
gpiod_set_array_value(j, descs, NULL, values);
|
||||
|
||||
if (chip->can_sleep)
|
||||
mutex_unlock(&fwd->mlock);
|
||||
else
|
||||
spin_unlock_irqrestore(&fwd->slock, flags);
|
||||
}
|
||||
|
||||
static int gpio_fwd_set_config(struct gpio_chip *chip, unsigned int offset,
|
||||
unsigned long config)
|
||||
{
|
||||
struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
|
||||
|
||||
return gpiod_set_config(fwd->descs[offset], config);
|
||||
}
|
||||
|
||||
/**
|
||||
* gpiochip_fwd_create() - Create a new GPIO forwarder
|
||||
* @dev: Parent device pointer
|
||||
* @ngpios: Number of GPIOs in the forwarder.
|
||||
* @descs: Array containing the GPIO descriptors to forward to.
|
||||
* This array must contain @ngpios entries, and must not be deallocated
|
||||
* before the forwarder has been destroyed again.
|
||||
*
|
||||
* This function creates a new gpiochip, which forwards all GPIO operations to
|
||||
* the passed GPIO descriptors.
|
||||
*
|
||||
* Return: An opaque object pointer, or an ERR_PTR()-encoded negative error
|
||||
* code on failure.
|
||||
*/
|
||||
static struct gpiochip_fwd *gpiochip_fwd_create(struct device *dev,
|
||||
unsigned int ngpios,
|
||||
struct gpio_desc *descs[])
|
||||
{
|
||||
const char *label = dev_name(dev);
|
||||
struct gpiochip_fwd *fwd;
|
||||
struct gpio_chip *chip;
|
||||
unsigned int i;
|
||||
int error;
|
||||
|
||||
fwd = devm_kzalloc(dev, struct_size(fwd, tmp,
|
||||
BITS_TO_LONGS(ngpios) + ngpios), GFP_KERNEL);
|
||||
if (!fwd)
|
||||
return ERR_PTR(-ENOMEM);
|
||||
|
||||
chip = &fwd->chip;
|
||||
|
||||
/*
|
||||
* If any of the GPIO lines are sleeping, then the entire forwarder
|
||||
* will be sleeping.
|
||||
* If any of the chips support .set_config(), then the forwarder will
|
||||
* support setting configs.
|
||||
*/
|
||||
for (i = 0; i < ngpios; i++) {
|
||||
struct gpio_chip *parent = gpiod_to_chip(descs[i]);
|
||||
|
||||
dev_dbg(dev, "%u => gpio-%d\n", i, desc_to_gpio(descs[i]));
|
||||
|
||||
if (gpiod_cansleep(descs[i]))
|
||||
chip->can_sleep = true;
|
||||
if (parent && parent->set_config)
|
||||
chip->set_config = gpio_fwd_set_config;
|
||||
}
|
||||
|
||||
chip->label = label;
|
||||
chip->parent = dev;
|
||||
chip->owner = THIS_MODULE;
|
||||
chip->get_direction = gpio_fwd_get_direction;
|
||||
chip->direction_input = gpio_fwd_direction_input;
|
||||
chip->direction_output = gpio_fwd_direction_output;
|
||||
chip->get = gpio_fwd_get;
|
||||
chip->get_multiple = gpio_fwd_get_multiple;
|
||||
chip->set = gpio_fwd_set;
|
||||
chip->set_multiple = gpio_fwd_set_multiple;
|
||||
chip->base = -1;
|
||||
chip->ngpio = ngpios;
|
||||
fwd->descs = descs;
|
||||
|
||||
if (chip->can_sleep)
|
||||
mutex_init(&fwd->mlock);
|
||||
else
|
||||
spin_lock_init(&fwd->slock);
|
||||
|
||||
error = devm_gpiochip_add_data(dev, chip, fwd);
|
||||
if (error)
|
||||
return ERR_PTR(error);
|
||||
|
||||
return fwd;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* GPIO Aggregator platform device
|
||||
*/
|
||||
|
||||
static int gpio_aggregator_probe(struct platform_device *pdev)
|
||||
{
|
||||
struct device *dev = &pdev->dev;
|
||||
struct gpio_desc **descs;
|
||||
struct gpiochip_fwd *fwd;
|
||||
int i, n;
|
||||
|
||||
n = gpiod_count(dev, NULL);
|
||||
if (n < 0)
|
||||
return n;
|
||||
|
||||
descs = devm_kmalloc_array(dev, n, sizeof(*descs), GFP_KERNEL);
|
||||
if (!descs)
|
||||
return -ENOMEM;
|
||||
|
||||
for (i = 0; i < n; i++) {
|
||||
descs[i] = devm_gpiod_get_index(dev, NULL, i, GPIOD_ASIS);
|
||||
if (IS_ERR(descs[i]))
|
||||
return PTR_ERR(descs[i]);
|
||||
}
|
||||
|
||||
fwd = gpiochip_fwd_create(dev, n, descs);
|
||||
if (IS_ERR(fwd))
|
||||
return PTR_ERR(fwd);
|
||||
|
||||
platform_set_drvdata(pdev, fwd);
|
||||
return 0;
|
||||
}
|
||||
|
||||
#ifdef CONFIG_OF
|
||||
static const struct of_device_id gpio_aggregator_dt_ids[] = {
|
||||
/*
|
||||
* Add GPIO-operated devices controlled from userspace below,
|
||||
* or use "driver_override" in sysfs
|
||||
*/
|
||||
{},
|
||||
};
|
||||
MODULE_DEVICE_TABLE(of, gpio_aggregator_dt_ids);
|
||||
#endif
|
||||
|
||||
static struct platform_driver gpio_aggregator_driver = {
|
||||
.probe = gpio_aggregator_probe,
|
||||
.driver = {
|
||||
.name = DRV_NAME,
|
||||
.groups = gpio_aggregator_groups,
|
||||
.of_match_table = of_match_ptr(gpio_aggregator_dt_ids),
|
||||
},
|
||||
};
|
||||
|
||||
static int __init gpio_aggregator_init(void)
|
||||
{
|
||||
return platform_driver_register(&gpio_aggregator_driver);
|
||||
}
|
||||
module_init(gpio_aggregator_init);
|
||||
|
||||
static void __exit gpio_aggregator_exit(void)
|
||||
{
|
||||
gpio_aggregator_remove_all();
|
||||
platform_driver_unregister(&gpio_aggregator_driver);
|
||||
}
|
||||
module_exit(gpio_aggregator_exit);
|
||||
|
||||
MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>");
|
||||
MODULE_DESCRIPTION("GPIO Aggregator");
|
||||
MODULE_LICENSE("GPL v2");
|
||||
|
|
@ -4622,7 +4622,7 @@ static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
|
|||
if (!table)
|
||||
return desc;
|
||||
|
||||
for (p = &table->table[0]; p->chip_label; p++) {
|
||||
for (p = &table->table[0]; p->key; p++) {
|
||||
struct gpio_chip *gc;
|
||||
|
||||
/* idx must always match exactly */
|
||||
|
|
@ -4633,18 +4633,30 @@ static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
|
|||
if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
|
||||
continue;
|
||||
|
||||
gc = find_chip_by_name(p->chip_label);
|
||||
if (p->chip_hwnum == U16_MAX) {
|
||||
desc = gpio_name_to_desc(p->key);
|
||||
if (desc) {
|
||||
*flags = p->flags;
|
||||
return desc;
|
||||
}
|
||||
|
||||
dev_warn(dev, "cannot find GPIO line %s, deferring\n",
|
||||
p->key);
|
||||
return ERR_PTR(-EPROBE_DEFER);
|
||||
}
|
||||
|
||||
gc = find_chip_by_name(p->key);
|
||||
|
||||
if (!gc) {
|
||||
/*
|
||||
* As the lookup table indicates a chip with
|
||||
* p->chip_label should exist, assume it may
|
||||
* p->key should exist, assume it may
|
||||
* still appear later and let the interested
|
||||
* consumer be probed again or let the Deferred
|
||||
* Probe infrastructure handle the error.
|
||||
*/
|
||||
dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
|
||||
p->chip_label);
|
||||
p->key);
|
||||
return ERR_PTR(-EPROBE_DEFER);
|
||||
}
|
||||
|
||||
|
|
@ -4675,7 +4687,7 @@ static int platform_gpio_count(struct device *dev, const char *con_id)
|
|||
if (!table)
|
||||
return -ENOENT;
|
||||
|
||||
for (p = &table->table[0]; p->chip_label; p++) {
|
||||
for (p = &table->table[0]; p->key; p++) {
|
||||
if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
|
||||
(!con_id && !p->con_id))
|
||||
count++;
|
||||
|
|
|
|||
|
|
@ -1439,9 +1439,9 @@ static int i801_add_mux(struct i801_priv *priv)
|
|||
return -ENOMEM;
|
||||
lookup->dev_id = "i2c-mux-gpio";
|
||||
for (i = 0; i < mux_config->n_gpios; i++) {
|
||||
lookup->table[i].chip_label = mux_config->gpio_chip;
|
||||
lookup->table[i].chip_hwnum = mux_config->gpios[i];
|
||||
lookup->table[i].con_id = "mux";
|
||||
lookup->table[i] = (struct gpiod_lookup)
|
||||
GPIO_LOOKUP(mux_config->gpio_chip,
|
||||
mux_config->gpios[i], "mux", 0);
|
||||
}
|
||||
gpiod_add_lookup_table(lookup);
|
||||
priv->lookup = lookup;
|
||||
|
|
|
|||
|
|
@ -1145,22 +1145,14 @@ static int sm501_register_gpio_i2c_instance(struct sm501_devdata *sm,
|
|||
return -ENOMEM;
|
||||
|
||||
lookup->dev_id = "i2c-gpio";
|
||||
if (iic->pin_sda < 32)
|
||||
lookup->table[0].chip_label = "SM501-LOW";
|
||||
else
|
||||
lookup->table[0].chip_label = "SM501-HIGH";
|
||||
lookup->table[0].chip_hwnum = iic->pin_sda % 32;
|
||||
lookup->table[0].con_id = NULL;
|
||||
lookup->table[0].idx = 0;
|
||||
lookup->table[0].flags = GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN;
|
||||
if (iic->pin_scl < 32)
|
||||
lookup->table[1].chip_label = "SM501-LOW";
|
||||
else
|
||||
lookup->table[1].chip_label = "SM501-HIGH";
|
||||
lookup->table[1].chip_hwnum = iic->pin_scl % 32;
|
||||
lookup->table[1].con_id = NULL;
|
||||
lookup->table[1].idx = 1;
|
||||
lookup->table[1].flags = GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN;
|
||||
lookup->table[0] = (struct gpiod_lookup)
|
||||
GPIO_LOOKUP_IDX(iic->pin_sda < 32 ? "SM501-LOW" : "SM501-HIGH",
|
||||
iic->pin_sda % 32, NULL, 0,
|
||||
GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN);
|
||||
lookup->table[1] = (struct gpiod_lookup)
|
||||
GPIO_LOOKUP_IDX(iic->pin_scl < 32 ? "SM501-LOW" : "SM501-HIGH",
|
||||
iic->pin_scl % 32, NULL, 1,
|
||||
GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN);
|
||||
gpiod_add_lookup_table(lookup);
|
||||
|
||||
icd = dev_get_platdata(&pdev->dev);
|
||||
|
|
|
|||
|
|
@ -20,8 +20,11 @@ enum gpio_lookup_flags {
|
|||
|
||||
/**
|
||||
* struct gpiod_lookup - lookup table
|
||||
* @chip_label: name of the chip the GPIO belongs to
|
||||
* @chip_hwnum: hardware number (i.e. relative to the chip) of the GPIO
|
||||
* @key: either the name of the chip the GPIO belongs to, or the GPIO line name
|
||||
* Note that GPIO line names are not guaranteed to be globally unique,
|
||||
* so this will use the first match found!
|
||||
* @chip_hwnum: hardware number (i.e. relative to the chip) of the GPIO, or
|
||||
* U16_MAX to indicate that @key is a GPIO line name
|
||||
* @con_id: name of the GPIO from the device's point of view
|
||||
* @idx: index of the GPIO in case several GPIOs share the same name
|
||||
* @flags: bitmask of gpio_lookup_flags GPIO_* values
|
||||
|
|
@ -30,7 +33,7 @@ enum gpio_lookup_flags {
|
|||
* functions using platform data.
|
||||
*/
|
||||
struct gpiod_lookup {
|
||||
const char *chip_label;
|
||||
const char *key;
|
||||
u16 chip_hwnum;
|
||||
const char *con_id;
|
||||
unsigned int idx;
|
||||
|
|
@ -63,17 +66,17 @@ struct gpiod_hog {
|
|||
/*
|
||||
* Simple definition of a single GPIO under a con_id
|
||||
*/
|
||||
#define GPIO_LOOKUP(_chip_label, _chip_hwnum, _con_id, _flags) \
|
||||
GPIO_LOOKUP_IDX(_chip_label, _chip_hwnum, _con_id, 0, _flags)
|
||||
#define GPIO_LOOKUP(_key, _chip_hwnum, _con_id, _flags) \
|
||||
GPIO_LOOKUP_IDX(_key, _chip_hwnum, _con_id, 0, _flags)
|
||||
|
||||
/*
|
||||
* Use this macro if you need to have several GPIOs under the same con_id.
|
||||
* Each GPIO needs to use a different index and can be accessed using
|
||||
* gpiod_get_index()
|
||||
*/
|
||||
#define GPIO_LOOKUP_IDX(_chip_label, _chip_hwnum, _con_id, _idx, _flags) \
|
||||
#define GPIO_LOOKUP_IDX(_key, _chip_hwnum, _con_id, _idx, _flags) \
|
||||
{ \
|
||||
.chip_label = _chip_label, \
|
||||
.key = _key, \
|
||||
.chip_hwnum = _chip_hwnum, \
|
||||
.con_id = _con_id, \
|
||||
.idx = _idx, \
|
||||
|
|
|
|||
Loading…
Reference in New Issue