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402 Commits

Author SHA1 Message Date
Linus Torvalds f632a8170a Driver Core and debugfs changes for 5.3-rc1
Here is the "big" driver core and debugfs changes for 5.3-rc1
 
 It's a lot of different patches, all across the tree due to some api
 changes and lots of debugfs cleanups.  Because of this, there is going
 to be some merge issues with your tree at the moment, I'll follow up
 with the expected resolutions to make it easier for you.
 
 Other than the debugfs cleanups, in this set of changes we have:
 	- bus iteration function cleanups (will cause build warnings
 	  with s390 and coresight drivers in your tree)
 	- scripts/get_abi.pl tool to display and parse Documentation/ABI
 	  entries in a simple way
 	- cleanups to Documenatation/ABI/ entries to make them parse
 	  easier due to typos and other minor things
 	- default_attrs use for some ktype users
 	- driver model documentation file conversions to .rst
 	- compressed firmware file loading
 	- deferred probe fixes
 
 All of these have been in linux-next for a while, with a bunch of merge
 issues that Stephen has been patient with me for.  Other than the merge
 issues, functionality is working properly in linux-next :)
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core and debugfs updates from Greg KH:
 "Here is the "big" driver core and debugfs changes for 5.3-rc1

  It's a lot of different patches, all across the tree due to some api
  changes and lots of debugfs cleanups.

  Other than the debugfs cleanups, in this set of changes we have:

   - bus iteration function cleanups

   - scripts/get_abi.pl tool to display and parse Documentation/ABI
     entries in a simple way

   - cleanups to Documenatation/ABI/ entries to make them parse easier
     due to typos and other minor things

   - default_attrs use for some ktype users

   - driver model documentation file conversions to .rst

   - compressed firmware file loading

   - deferred probe fixes

  All of these have been in linux-next for a while, with a bunch of
  merge issues that Stephen has been patient with me for"

* tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (102 commits)
  debugfs: make error message a bit more verbose
  orangefs: fix build warning from debugfs cleanup patch
  ubifs: fix build warning after debugfs cleanup patch
  driver: core: Allow subsystems to continue deferring probe
  drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT
  arch_topology: Remove error messages on out-of-memory conditions
  lib: notifier-error-inject: no need to check return value of debugfs_create functions
  swiotlb: no need to check return value of debugfs_create functions
  ceph: no need to check return value of debugfs_create functions
  sunrpc: no need to check return value of debugfs_create functions
  ubifs: no need to check return value of debugfs_create functions
  orangefs: no need to check return value of debugfs_create functions
  nfsd: no need to check return value of debugfs_create functions
  lib: 842: no need to check return value of debugfs_create functions
  debugfs: provide pr_fmt() macro
  debugfs: log errors when something goes wrong
  drivers: s390/cio: Fix compilation warning about const qualifiers
  drivers: Add generic helper to match by of_node
  driver_find_device: Unify the match function with class_find_device()
  bus_find_device: Unify the match callback with class_find_device
  ...
2019-07-12 12:24:03 -07:00
Mark Brown 26ac56506b
Merge remote-tracking branch 'spi/topic/pump-rt' into spi-next 2019-07-04 17:35:11 +01:00
Ard Biesheuvel b28944c6f6
spi/acpi: avoid spurious matches during slave enumeration
In the new SPI ACPI slave enumeration code, we use the value of
lookup.max_speed_khz as a flag to decide whether a match occurred.
However, doing so only makes sense if we initialize its value to
zero beforehand, or otherwise, random junk from the stack will
cause spurious matches.

So zero initialize the lookup struct fully, and only set the non-zero
members explicitly.

Fixes: 4c3c59544f ("spi/acpi: enumerate all SPI slaves in the namespace")
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: andy.shevchenko@gmail.com
Cc: masahisa.kojima@linaro.org
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Cc: linux-acpi@vger.kernel.org
Cc: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-06-24 17:30:34 +01:00
Suzuki K Poulose 418e3ea157 bus_find_device: Unify the match callback with class_find_device
There is an arbitrary difference between the prototypes of
bus_find_device() and class_find_device() preventing their callers
from passing the same pair of data and match() arguments to both of
them, which is the const qualifier used in the prototype of
class_find_device().  If that qualifier is also used in the
bus_find_device() prototype, it will be possible to pass the same
match() callback function to both bus_find_device() and
class_find_device(), which will allow some optimizations to be made in
order to avoid code duplication going forward.  Also with that, constify
the "data" parameter as it is passed as a const to the match function.

For this reason, change the prototype of bus_find_device() to match
the prototype of class_find_device() and adjust its callers to use the
const qualifier in accordance with the new prototype of it.

Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Andreas Noever <andreas.noever@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Corey Minyard <minyard@acm.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Kershner <david.kershner@unisys.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: David Airlie <airlied@linux.ie>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Harald Freudenberger <freude@linux.ibm.com>
Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Jamet <michael.jamet@intel.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: Sebastian Ott <sebott@linux.ibm.com>
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Cc: Yehezkel Bernat <YehezkelShB@gmail.com>
Cc: rafael@kernel.org
Acked-by: Corey Minyard <minyard@acm.org>
Acked-by: David Kershner <david.kershner@unisys.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de> # for the I2C parts
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-24 05:22:31 +02:00
Tudor Ambarus f9481b0822
spi: fix ctrl->num_chipselect constraint
at91sam9g25ek showed the following error at probe:
atmel_spi f0000000.spi: Using dma0chan2 (tx) and dma0chan3 (rx)
for DMA transfers
atmel_spi: probe of f0000000.spi failed with error -22

Commit 0a919ae492 ("spi: Don't call spi_get_gpio_descs() before device name is set")
moved the calling of spi_get_gpio_descs() after ctrl->dev is set,
but didn't move the !ctrl->num_chipselect check. When there are
chip selects in the device tree, the spi-atmel driver lets the
SPI core discover them when registering the SPI master.
The ctrl->num_chipselect is thus expected to be set by
spi_get_gpio_descs().

Move the !ctlr->num_chipselect after spi_get_gpio_descs() as it was
before the aforementioned commit. While touching this block, get rid
of the explicit comparison with 0 and update the commenting style.

Fixes: 0a919ae492 ("spi: Don't call spi_get_gpio_descs() before device name is set")
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-06-20 13:08:48 +01:00
Ard Biesheuvel b5e3cf410b
spi/acpi: fix incorrect ACPI parent check
The ACPI device object parsing code for SPI slaves enumerates the
entire ACPI namespace to look for devices that refer to the master
in question via the 'resource_source' field in the 'SPISerialBus'
resource. If that field does not refer to a valid ACPI device or
if it refers to the wrong SPI master, we should disregard the
device.

Current, the valid device check is wrong, since it gets the
polarity of 'status' wrong. This could cause issues if the
'resource_source' field is bogus but parent_handle happens to
refer to the correct master (which is not entirely imaginary
since this code runs in a loop)

So test for ACPI_FAILURE() instead, to make the code more
self explanatory.

Fixes: 4c3c59544f ("spi/acpi: enumerate all SPI slaves in the namespace")
Reported-by: kbuild test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: andy.shevchenko@gmail.com
Cc: masahisa.kojima@linaro.org
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Cc: linux-acpi@vger.kernel.org
Cc: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-06-19 11:54:29 +01:00
Vladimir Zapolskiy f569436994
spi: don't open code list_for_each_entry_safe_reverse()
The loop declaration in function spi_res_release() can be simplified
by reusing the common list_for_each_entry_safe_reverse() helper
macro.

Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-06-18 19:19:14 +01:00
Andy Shevchenko ebc37af5e0
spi: No need to assign dummy value in spi_unregister_controller()
The device_for_each_child() doesn't require the returned value to be checked.
Thus, drop the dummy variable completely and have no warning anymore:

drivers/spi/spi.c: In function ‘spi_unregister_controller’:
drivers/spi/spi.c:2480:6: warning: variable ‘dummy’ set but not used [-Wunused-but-set-variable]
  int dummy;
      ^~~~~

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-06-17 13:50:52 +01:00
Ard Biesheuvel 4c3c59544f
spi/acpi: enumerate all SPI slaves in the namespace
Currently, the ACPI enumeration that takes place when registering a
SPI master only considers immediate child devices in the ACPI namespace,
rather than checking the ResourceSource field in the SpiSerialBus()
resource descriptor.

This is incorrect: SPI slaves could reside anywhere in the ACPI
namespace, and so we should enumerate the entire namespace and look for
any device that refers to the newly registered SPI master in its
resource descriptor.

So refactor the existing code and use a lookup structure so that
allocating the SPI device structure is deferred until we have identified
the device as an actual child of the controller. This approach is
loosely based on the way the I2C subsystem handles ACPI enumeration.

Note that Apple x86 hardware does not rely on SpiSerialBus() resources
in _CRS but uses nested devices below the controller's device node in
the ACPI namespace, with a special set of device properties. This means
we have to take care to only parse those properties for device nodes
that are direct children of the controller node.

Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: linux-spi@vger.kernel.org
Cc: broonie@kernel.org
Cc: andy.shevchenko@gmail.com
Cc: masahisa.kojima@linaro.org
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Cc: linux-acpi@vger.kernel.org
Cc: Lukas Wunner <lukas@wunner.de>

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-06-13 20:04:32 +01:00
Gustavo A. R. Silva aef9752274
spi: Use struct_size() helper
One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct spi_replaced_transfers {
	...
        struct spi_transfer inserted_transfers[];
};

Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes.

So, replace the following form:

insert * sizeof(struct spi_transfer) + sizeof(struct spi_replaced_transfers)

with:

struct_size(rxfer, inserted_transfers, insert)

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-06-10 15:42:09 +01:00
Mark Brown d9424d6d48
Merge branch 'spi-5.2' into spi-5.3 2019-05-23 14:47:04 +01:00
Douglas Anderson 924b5867e7
spi: Allow SPI devices to request the pumping thread be realtime
Right now the only way to get the SPI pumping thread bumped up to
realtime priority is for the controller to request it.  However it may
be that the controller works fine with the normal priority but
communication to a particular SPI device on the bus needs realtime
priority.

Let's add a way for devices to request realtime priority when they set
themselves up.

NOTE: this will just affect the priority of transfers that end up on
the SPI core's pumping thread.  In many cases transfers happen in the
context of the caller so if you need realtime priority for all
transfers you should ensure the calling context is also realtime
priority.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Tested-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-23 14:44:02 +01:00
Super Liu f3440d9a0d
spi: abort spi_sync if failed to prepare_transfer_hardware
There is no chance to wait spi message complete if failed to
prepare_transfer_hardware(). Therefore, finalize this message and abort
transfer with corresponding return status to release this block case.

Logs:

[17400.283005] c7   3267 PM: PM: suspend entry 2019-05-04 03:01:14.403097147 UTC
[17400.283013] c7   3267 PM: suspend entry (deep)
[17400.283016] c6   3267 PM: Syncing filesystems ... done.
[17400.584395] c1    753 spi_geni 890000.spi: spi_geni_prepare_transfer_hardware:Error enabling SE resources -13
[17400.584404] c1    753 spi_master spi1: failed to prepare transfer hardware
[17400.664611] c4   3267 PM: PM: suspend exit 2019-05-04 03:01:15.235273018 UTC

Flow:

__spi_sync@spi.c
|    if (status == 0) {
|        /* Push out the messages in the calling context if we
|         * can.
|         */
|        if (ctlr->transfer == spi_queued_transfer) {
|            SPI_STATISTICS_INCREMENT_FIELD(&ctlr->statistics,
|		spi_sync_immediate);
|            SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics,
|		spi_sync_immediate);
|		__spi_pump_messages(ctlr, false);
|        }
|
|        wait_for_completion(&done);	<== stuck here!!!
|        status = message->status;
|    }
|    message->context = NULL;
|    return status;
|
-->	__spi_pump_messages@spi.c
	|    if (!was_busy && ctlr->prepare_transfer_hardware) {
	|        ret = ctlr->prepare_transfer_hardware(ctlr);
	|        if (ret) {
	|            dev_err(&ctlr->dev,
	|		"failed to prepare transfer hardware\n");
	|
	|        if (ctlr->auto_runtime_pm)
	|            pm_runtime_put(ctlr->dev.parent);
	|            mutex_unlock(&ctlr->io_mutex);
	|            return;
	|        }
	|    }
	|
	-->	spi_geni_prepare_transfer_hardware@spi-geni-qcom.c
		|    ret = pm_runtime_get_sync(mas->dev);
		|    if (ret < 0) {
		|        dev_err(mas->dev,
		|		"%s:Error enabling SE resources %d\n",
		|		__func__, ret);
		|    pm_runtime_put_noidle(mas->dev);
		|    goto exit_prepare_transfer_hardware;

Signed-off-by: Super Liu <supercjliu@google.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-23 14:36:13 +01:00
Martin Sperl 5d7e2b5ed5
spi: core: allow reporting the effectivly used speed_hz for a transfer
Provide a means for the spi bus driver to report the effectively used
spi clock frequency used for each spi_transfer.

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-13 13:11:36 +01:00
Mark Brown 0ed56252c9
spi: Fix Raspberry Pi breakage
This reverts commit c9ba7a16d0 (Release spi_res after finalizing
message) which causes races during cleanup.

Reported-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-09 11:27:17 +09:00
Martin Sperl d5864e5bed
spi: core: allow defining time that cs is deasserted as a multiple of SCK
Support setting a delay between cs assert and deassert as
a multiple of spi clock length.

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-08 18:30:01 +09:00
Martin Sperl 0ff2de8bb1
spi: core: allow defining time that cs is deasserted
For some SPI devices that support speed_hz > 1MHz the default 10 us delay
when cs_change = 1 is typically way to long and may result in poor spi bus
utilization.

This patch makes it possible to control the delay at micro or nano second
resolution on a per spi_transfer basis. It even allows an "as fast as
possible" mode with:
    xfer.cs_change_delay_unit = SPI_DELAY_UNIT_NSECS;
    xfer.cs_change_delay = 0;

The delay code is shared between delay_usecs and cs_change_delay for
consistency and reuse, so in the future this change_delay_unit could also
apply to delay_usec as well.

Note that on slower SOCs/CPU actually reaching ns deasserts on cs is not
realistic as the gpio overhead alone (without any delays added ) may
already leave cs deasserted for more than 1us - at least on a raspberry pi.
But at the very least this way we can keep it as short as possible.

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-08 18:28:51 +09:00
Serge Semin d61ad23cb3
spi: Clear SPI_CS_HIGH flag from bad_bits for GPIO chip-select
When GPIO chip-select is used nothing prevents any available SPI
controllers to work with both CS-high and traditional CS-low modes.
In fact the SPI bus core code already does it, so we don't need to
introduce any modification there. But spi_setup() still fails to
switch the interface settings if CS-high flag is set for the case
of GPIO-driven slave chip-select when the SPI controller doesn't
support the hardwired CS-inversion. Lets fix it by clearing the
SPI_CS_HIGH flag out from bad_bits (unsupported by controller) when
client chip is selected by GPIO.

This feature is useful for slave devices, which in accordance with
communication protocol can work with both active-high and active-low
chip-selects. I am aware of one such device. It is MMC-SPI interface,
when at init sequence the driver needs to perform a read operation with
low and high chip-select sequentially (requirement of 74 clock cycles
with both chipselect, see the mmc_spi driver for details).

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-02 10:38:00 +09:00
Noralf Trønnes c9ba7a16d0
spi: Release spi_res after finalizing message
spi_split_transfers_maxsize() can be used to split a transfer. This
function uses spi_res to lifetime manage the added transfer structures.
So in order to finalize the current message while it contains the split
transfers, spi_res_release() must be called after finalizing.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-02 10:37:51 +09:00
Noralf Trønnes 4d1841d645
spi: Remove warning in spi_split_transfers_maxsize()
Don't warn about splitting transfers, the info is available in the
statistics if needed.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-02 10:37:50 +09:00
Jarkko Nikula 76d2f7ee68
spi: Remove one needless transfer speed fall back case
Falling back to maximum speed of the controller in case of SPI slave
maximum speed is not set is needless. It already defaults to maximum
speed of the controller since commit 052eb2d490 ("spi: core: Set
max_speed_hz of spi_device default to max_speed_hz of controller").

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-02 10:37:49 +09:00
Sowjanya Komatineni f1ca9992ce
spi: add a method for configuring CS timing
This patch creates set_cs_timing SPI master optional method for
SPI masters to implement configuring CS timing if applicable.

This patch also creates spi_cs_timing accessory for SPI clients to
use for requesting SPI master controllers to configure device requested
CS setup time, hold time and inactive delay.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-04-08 14:14:10 +07:00
Sergei Shtylyov b93318a22f
spi: kill useless initializer in spi_register_controller()
The 'status' local variable is initialized but this value is never used,
thus kill that initializer.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-04-08 14:05:40 +07:00
Andrey Smirnov 0a919ae492
spi: Don't call spi_get_gpio_descs() before device name is set
Move code calling spi_get_gpio_descs() to happen after ctlr->dev's
name is set in order to have proper GPIO consumer names.

Before:

cat /sys/kernel/debug/gpio
gpiochip0: GPIOs 0-31, parent: platform/40049000.gpio, vf610-gpio:
 gpio-6   (                    |regulator-usb0-vbus ) out lo

gpiochip1: GPIOs 32-63, parent: platform/4004a000.gpio, vf610-gpio:
 gpio-36  (                    |scl                 ) in  hi
 gpio-37  (                    |sda                 ) in  hi
 gpio-40  (                    |(null) CS1          ) out lo
 gpio-41  (                    |(null) CS0          ) out lo ACTIVE LOW
 gpio-42  (                    |miso                ) in  hi
 gpio-43  (                    |mosi                ) in  lo
 gpio-44  (                    |sck                 ) out lo

After:

cat /sys/kernel/debug/gpio
gpiochip0: GPIOs 0-31, parent: platform/40049000.gpio, vf610-gpio:
 gpio-6   (                    |regulator-usb0-vbus ) out lo

gpiochip1: GPIOs 32-63, parent: platform/4004a000.gpio, vf610-gpio:
 gpio-36  (                    |scl                 ) in  hi
 gpio-37  (                    |sda                 ) in  hi
 gpio-40  (                    |spi0 CS1            ) out lo
 gpio-41  (                    |spi0 CS0            ) out lo ACTIVE LOW
 gpio-42  (                    |miso                ) in  hi
 gpio-43  (                    |mosi                ) in  lo
 gpio-44  (                    |sck                 ) out lo

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Chris Healy <cphealy@gmail.com>
Cc: linux-spi@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-04-05 10:23:28 +07:00
Mark Brown e1a7d16730
Merge branch 'spi-5.1' into spi-5.2 2019-04-05 10:19:10 +07:00
Geert Uytterhoeven 1723fdec5f
spi: Add missing error handling for CS GPIOs
While devm_gpiod_get_index_optional() returns NULL if the GPIO is not
present (i.e. -ENOENT), it may still return other error codes, like
-EPROBE_DEFER.  Currently these are not handled, leading to
unrecoverable failures later in case of probe deferral:

    gpiod_set_consumer_name: invalid GPIO (errorpointer)
    gpiod_direction_output: invalid GPIO (errorpointer)
    gpiod_set_value_cansleep: invalid GPIO (errorpointer)
    gpiod_set_value_cansleep: invalid GPIO (errorpointer)
    gpiod_set_value_cansleep: invalid GPIO (errorpointer)

Detect and propagate errors to fix this.

Fixes: f3186dd876 ("spi: Optionally use GPIO descriptors for CS GPIOs")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-04-04 12:58:18 +07:00
Arnd Bergmann ca1438dcb3
spi: export tracepoint symbols to modules
The newly added tracepoints in the spi-mxs driver cause a link
error when the driver is a loadable module:

ERROR: "__tracepoint_spi_transfer_stop" [drivers/spi/spi-mxs.ko] undefined!
ERROR: "__tracepoint_spi_transfer_start" [drivers/spi/spi-mxs.ko] undefined!

I'm not quite sure where to put the export statements, but
directly after the inclusion of the header seems as good as
any other place.

Fixes: f3fdea3af4 ("spi: mxs: add tracing to custom .transfer_one_message callback")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-03-21 15:05:07 +00:00
Chris Lesiak 5442dcaa0d
spi: Fix zero length xfer bug
This fixes a bug for messages containing both zero length and
unidirectional xfers.

The function spi_map_msg will allocate dummy tx and/or rx buffers
for use with unidirectional transfers when the hardware can only do
a bidirectional transfer.  That dummy buffer will be used in place
of a NULL buffer even when the xfer length is 0.

Then in the function __spi_map_msg, if he hardware can dma,
the zero length xfer will have spi_map_buf called on the dummy
buffer.

Eventually, __sg_alloc_table is called and returns -EINVAL
because nents == 0.

This fix prevents the error by not using the dummy buffer when
the xfer length is zero.

Signed-off-by: Chris Lesiak <chris.lesiak@licor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-03-11 16:40:00 +00:00
Felix Fietkau 28f7604f48
spi: use gpio[d]_set_value_cansleep for setting chipselect GPIO
Sleeping is safe inside spi_transfer_one_message, and some
GPIO chips are running on slow busses (such as I2C GPIO
expanders) and need to sleep for setting values.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-02-12 16:41:11 +00:00
Jonas Bonn b7bb367afa
spi: support inter-word delay requirement for devices
Some devices are slow and cannot keep up with the SPI bus and therefore
require a short delay between words of the SPI transfer.

The example of this that I'm looking at is a SAMA5D2 with a minimum SPI
clock of 400kHz talking to an AVR-based SPI slave.  The AVR cannot put
bytes on the bus fast enough to keep up with the SoC's SPI controller
even at the lowest bus speed.

This patch introduces the ability to specify a required inter-word
delay for SPI devices.  It is up to the controller driver to configure
itself accordingly in order to introduce the requested delay.

Note that, for spi_transfer, there is already a field word_delay that
provides similar functionality.  This field, however, is specified in
clock cycles (and worse, SPI controller cycles, not SCK cycles); that
makes this value dependent on the master clock instead of the device
clock for which the delay is intended to provide some relief.  This
patch leaves this old word_delay in place and provides a time-based
word_delay_us alongside it; the new field fits in the struct padding
so struct size is constant.  There is only one in-kernel user of the
word_delay field and presumably that driver could be reworked to use
the time-based value instead.

The time-based delay is limited to 8 bits as these delays are intended
to be short.  The SAMA5D2 that I've tested this on limits delays to a
maximum of ~100us, which is already many word-transfer periods even at
the minimum transfer speed supported by the controller.

Signed-off-by: Jonas Bonn <jonas@norrbonn.se>
CC: Mark Brown <broonie@kernel.org>
CC: Rob Herring <robh+dt@kernel.org>
CC: Mark Rutland <mark.rutland@arm.com>
CC: linux-spi@vger.kernel.org
CC: devicetree@vger.kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-30 23:02:10 +00:00
Linus Walleij 2df201e006
spi: Support high CS when using descriptors
All controllers using GPIO descriptors can by definition
support high CS connections, so just enforce this when
registering an SPI controller.

This fixes a regression where controllers were missing
SPI_CS_HIGH, the drivers would fail like this:

spi spi0.0: setup: unsupported mode bits 4
cdns-spi fd0b0000.spi: can't setup spi0.0, status -22

This is because as using descriptors moves the CS inversion
logic over to gpiolib, all such controllers are registered
with CS active high.

Cc: Jan Kotas <jank@cadence.com>
Reported-by: Jan Kotas <jank@cadence.com>
Tested-by: Jan Kotas <jank@cadence.com>
Fixes: f3186dd876 ("spi: Optionally use GPIO descriptors for CS GPIOs")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-24 19:01:05 +00:00
Mark Brown f0125f1a55
spi: Go back to immediate teardown
Commit 412e603732 ("spi: core: avoid waking pump thread from spi_sync
instead run teardown delayed") introduced regressions on some boards,
apparently connected to spi_mem not triggering shutdown properly any
more.  Since we've thus far been unable to figure out exactly where the
breakage is revert the optimisation for now.

Reported-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: kernel@martin.sperl.org
2019-01-23 17:29:53 +00:00
Martin Sperl 412e603732
spi: core: avoid waking pump thread from spi_sync instead run teardown delayed
When spi_sync is running alone with no other spi devices connected
to the bus the worker thread is woken during spi_finalize_current_message
to run the teardown code every time.

This is totally unnecessary in the case that there is no message queued.

On a multi-core system this results in one wakeup of the thread for each
spi_message processed via spi_sync where in most cases the teardown does
not happen as the hw is already in use.

This patch now delays the teardown by 1 second by using a separate
kthread_delayed_work for the teardown.

This avoids waking the kthread too often.

For spi_sync transfers in a tight loop (say 40k messages/s) this
avoids the penalty of waking the worker thread 40k times/s.
On a rasperry pi 3 with 4 cores the results in 32% of a single core
only to find out that there is nothing in the queue and it can go back
to sleep.

With this patch applied the spi-worker is woken exactly once: after
the load finishes and the spi bus is idle for 1 second.

I believe I have also seen situations where during a spi_sync loop
the worker thread (triggered by the last message finished) is slightly
faster and _wins_ the race to process the message, so we are actually
running the kthread and letting it do some work...

This is also no longer observed with this patch applied as.

Tested with a new CAN controller driver for the mcp2517fd which
uses spi_sync for interrupt handling and spi_async for scheduling
of can frames for transmission (in a different thread)

Some statistics when receiving 100000 CAN frames with the mcp25xxfd driver
on a Raspberry pi 3:

without the patch:
------------------
root@raspcm3:~# for x in $(pgrep spi0) $(pgrep irq/94-mcp25xxf) ; do awk '{printf "%-20s %6i\n", $2,$15}' /proc/$x/stat; done
(spi0)                    5
(irq/94-mcp25xxf)         0
root@raspcm3:~# vmstat 1
procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu-----
 r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa st
 1  0      0 821960  13592  50848    0    0    80     2 1986  105  1  2 97  0  0
 0  0      0 821968  13592  50876    0    0     0     0 8046   30  0  0 100  0  0
 0  0      0 821936  13592  50876    0    0     0     0 8032   24  0  0 100  0  0
 0  0      0 821936  13592  50876    0    0     0     0 8035   30  0  0 100  0  0
 0  0      0 821936  13592  50876    0    0     0     0 8033   22  0  0 100  0  0
 2  0      0 821936  13592  50876    0    0     0     0 11598 7129  0  3 97  0  0
 1  0      0 821872  13592  50876    0    0     0     0 37741 59003  0 31 69  0  0
 2  0      0 821840  13592  50876    0    0     0     0 37762 59078  0 29 71  0  0
 2  0      0 821776  13592  50876    0    0     0     0 37593 58792  0 28 72  0  0
 1  0      0 821744  13592  50876    0    0     0     0 37642 58881  0 30 70  0  0
 2  0      0 821680  13592  50876    0    0     0     0 37490 58602  0 27 73  0  0
 1  0      0 821648  13592  50876    0    0     0     0 37412 58418  0 29 71  0  0
 1  0      0 821584  13592  50876    0    0     0     0 37337 58288  0 27 73  0  0
 1  0      0 821552  13592  50876    0    0     0     0 37584 58774  0 27 73  0  0
 0  0      0 821520  13592  50876    0    0     0     0 18363 20566  0  9 91  0  0
 0  0      0 821520  13592  50876    0    0     0     0 8037   32  0  0 100  0  0
 0  0      0 821520  13592  50876    0    0     0     0 8031   23  0  0 100  0  0
 0  0      0 821520  13592  50876    0    0     0     0 8034   26  0  0 100  0  0
 0  0      0 821520  13592  50876    0    0     0     0 8033   24  0  0 100  0  0
^C
root@raspcm3:~# for x in $(pgrep spi0) $(pgrep irq/94-mcp25xxf) ; do awk '{printf "%-20s %6i\n", $2,$15}' /proc/$x/stat; done
(spi0)                  228
(irq/94-mcp25xxf)       794
root@raspcm3:~# cat /proc/interrupts
           CPU0       CPU1       CPU2       CPU3
 17:         34          0          0          0  ARMCTRL-level   1 Edge      3f00b880.mailbox
 27:          1          0          0          0  ARMCTRL-level  35 Edge      timer
 33:    1416870          0          0          0  ARMCTRL-level  41 Edge      3f980000.usb, dwc2_hsotg:usb1
 34:          1          0          0          0  ARMCTRL-level  42 Edge      vc4
 35:          0          0          0          0  ARMCTRL-level  43 Edge      3f004000.txp
 40:       1753          0          0          0  ARMCTRL-level  48 Edge      DMA IRQ
 42:         11          0          0          0  ARMCTRL-level  50 Edge      DMA IRQ
 44:         11          0          0          0  ARMCTRL-level  52 Edge      DMA IRQ
 45:          0          0          0          0  ARMCTRL-level  53 Edge      DMA IRQ
 66:          0          0          0          0  ARMCTRL-level  74 Edge      vc4 crtc
 69:          0          0          0          0  ARMCTRL-level  77 Edge      vc4 crtc
 70:          0          0          0          0  ARMCTRL-level  78 Edge      vc4 crtc
 77:         20          0          0          0  ARMCTRL-level  85 Edge      3f205000.i2c, 3f804000.i2c, 3f805000.i2c
 78:       6346          0          0          0  ARMCTRL-level  86 Edge      3f204000.spi
 80:        205          0          0          0  ARMCTRL-level  88 Edge      mmc0
 81:        493          0          0          0  ARMCTRL-level  89 Edge      uart-pl011
 89:          0          0          0          0  bcm2836-timer   0 Edge      arch_timer
 90:       4291       3821       2180       1649  bcm2836-timer   1 Edge      arch_timer
 94:      14289          0          0          0  pinctrl-bcm2835  16 Level     mcp25xxfd
IPI0:          0          0          0          0  CPU wakeup interrupts
IPI1:          0          0          0          0  Timer broadcast interrupts
IPI2:       3645     242371       7919       1328  Rescheduling interrupts
IPI3:        112        543        273        194  Function call interrupts
IPI4:          0          0          0          0  CPU stop interrupts
IPI5:          1          0          0          0  IRQ work interrupts
IPI6:          0          0          0          0  completion interrupts
Err:          0

top shows 93% for the mcp25xxfd interrupt handler, 31% for spi0.

with the patch:
---------------
root@raspcm3:~# for x in $(pgrep spi0) $(pgrep irq/94-mcp25xxf) ; do awk '{printf "%-20s %6i\n", $2,$15}' /proc/$x/stat; done
(spi0)                    0
(irq/94-mcp25xxf)         0
root@raspcm3:~# vmstat 1
procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu-----
 0  0      0 804768  13584  62628    0    0     0     0 8038   24  0  0 100  0  0
 0  0      0 804768  13584  62628    0    0     0     0 8042   25  0  0 100  0  0
 1  0      0 804704  13584  62628    0    0     0     0 9603 2967  0 20 80  0  0
 1  0      0 804672  13584  62628    0    0     0     0 9828 3380  0 24 76  0  0
 1  0      0 804608  13584  62628    0    0     0     0 9823 3375  0 23 77  0  0
 1  0      0 804608  13584  62628    0    0     0    12 9829 3394  0 23 77  0  0
 1  0      0 804544  13584  62628    0    0     0     0 9816 3362  0 22 78  0  0
 1  0      0 804512  13584  62628    0    0     0     0 9817 3367  0 23 77  0  0
 1  0      0 804448  13584  62628    0    0     0     0 9822 3370  0 22 78  0  0
 1  0      0 804416  13584  62628    0    0     0     0 9815 3367  0 23 77  0  0
 0  0      0 804352  13584  62628    0    0     0    84 9222 2250  0 14 86  0  0
 0  0      0 804352  13592  62620    0    0     0    24 8131  209  0  0 93  7  0
 0  0      0 804320  13592  62628    0    0     0     0 8041   27  0  0 100  0  0
 0  0      0 804352  13592  62628    0    0     0     0 8040   26  0  0 100  0  0
root@raspcm3:~# for x in $(pgrep spi0) $(pgrep irq/94-mcp25xxf) ; do awk '{printf "%-20s %6i\n", $2,$15}' /proc/$x/stat; done
(spi0)                    0
(irq/94-mcp25xxf)       767
root@raspcm3:~# cat /proc/interrupts
           CPU0       CPU1       CPU2       CPU3
 17:         29          0          0          0  ARMCTRL-level   1 Edge      3f00b880.mailbox
 27:          1          0          0          0  ARMCTRL-level  35 Edge      timer
 33:    1024412          0          0          0  ARMCTRL-level  41 Edge      3f980000.usb, dwc2_hsotg:usb1
 34:          1          0          0          0  ARMCTRL-level  42 Edge      vc4
 35:          0          0          0          0  ARMCTRL-level  43 Edge      3f004000.txp
 40:       1773          0          0          0  ARMCTRL-level  48 Edge      DMA IRQ
 42:         11          0          0          0  ARMCTRL-level  50 Edge      DMA IRQ
 44:         11          0          0          0  ARMCTRL-level  52 Edge      DMA IRQ
 45:          0          0          0          0  ARMCTRL-level  53 Edge      DMA IRQ
 66:          0          0          0          0  ARMCTRL-level  74 Edge      vc4 crtc
 69:          0          0          0          0  ARMCTRL-level  77 Edge      vc4 crtc
 70:          0          0          0          0  ARMCTRL-level  78 Edge      vc4 crtc
 77:         20          0          0          0  ARMCTRL-level  85 Edge      3f205000.i2c, 3f804000.i2c, 3f805000.i2c
 78:       6417          0          0          0  ARMCTRL-level  86 Edge      3f204000.spi
 80:        237          0          0          0  ARMCTRL-level  88 Edge      mmc0
 81:        489          0          0          0  ARMCTRL-level  89 Edge      uart-pl011
 89:          0          0          0          0  bcm2836-timer   0 Edge      arch_timer
 90:       4048       3704       2383       1892  bcm2836-timer   1 Edge      arch_timer
 94:      14287          0          0          0  pinctrl-bcm2835  16 Level     mcp25xxfd
IPI0:          0          0          0          0  CPU wakeup interrupts
IPI1:          0          0          0          0  Timer broadcast interrupts
IPI2:       2361       2948       7890       1616  Rescheduling interrupts
IPI3:         65        617        301        166  Function call interrupts
IPI4:          0          0          0          0  CPU stop interrupts
IPI5:          1          0          0          0  IRQ work interrupts
IPI6:          0          0          0          0  completion interrupts
Err:          0
top shows 91% for the mcp25xxfd interrupt handler, 0% for spi0

So we see that spi0 is no longer getting scheduled wasting CPU cycles
There are a lot less context switches and corresponding Rescheduling interrupts
All of these show that this improves efficiency of the system and reduces
CPU utilization.

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-09 19:16:18 +00:00
Linus Walleij f3186dd876
spi: Optionally use GPIO descriptors for CS GPIOs
This augments the SPI core to optionally use GPIO descriptors
for chip select on a per-master-driver opt-in basis.

Drivers using this will rely on the SPI core to look up
GPIO descriptors associated with the device, such as
when using device tree or board files with GPIO descriptor
tables.

When getting descriptors from the device tree, this will in
turn activate the code in gpiolib that was
added in commit 6953c57ab1
("gpio: of: Handle SPI chipselect legacy bindings")
which means that these descriptors are aware of the active
low semantics that is the default for SPI CS GPIO lines
and we can assume that all of these are "active high" and
thus assign SPI_CS_HIGH to all CS lines on the DT path.

The previously used gpio_set_value() would call down into
gpiod_set_raw_value() and ignore the polarity inversion
semantics.

It seems like many drivers go to great lengths to set up the
CS GPIO line as non-asserted, respecting SPI_CS_HIGH. We pull
this out of the SPI drivers and into the core, and by simply
requesting the line as GPIOD_OUT_LOW when retrieveing it from
the device and relying on the gpiolib to handle any inversion
semantics. This way a lot of code can be simplified and
removed in each converted driver.

The end goal after dealing with each driver in turn, is to
delete the non-descriptor path (of_spi_register_master() for
example) and let the core deal with only descriptors.

The different SPI drivers have complex interactions with the
core so we cannot simply change them all over, we need to use
a stepwise, bisectable approach so that each driver can be
converted and fixed in isolation.

This patch has the intended side effect of adding support for
ACPI GPIOs as it starts relying on gpiod_get_*() to get
the GPIO handle associated with the device.

Cc: Linuxarm <linuxarm@huawei.com>
Acked-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Tested-by: Fangjian (Turing) <f.fangjian@huawei.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-09 12:39:25 +00:00
Rob Herring 194276b073
spi: Use of_node_name_eq for node name comparisons
Convert string compares of DT node names to use of_node_name_eq helper
instead. This removes direct access to the node name pointer.

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-06 20:15:43 +00:00
Yogesh Narayan Gaur 6b03061f88
spi: add support for octal mode I/O data transfer
Add flags for Octal mode I/O data transfer
Required for the SPI controller which can do the data transfer (TX/RX)
on 8 data lines e.g. NXP FlexSPI controller.
 SPI_TX_OCTAL: transmit with 8 wires
 SPI_RX_OCTAL: receive with 8 wires

Signed-off-by: Yogesh Gaur <yogeshnarayan.gaur@nxp.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-03 17:14:53 +00:00
Mark Brown 787f4889a6
spi: Fix formatting of header block
Make everything look intentional by having a C++ comment for the whole
block, not just the SPDX line.

Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-29 16:24:37 +00:00
Mark Brown d57e79601b
spi: Fix core transfer waits after slave support
The refactoring done as part of adding the core support for handling
waiting for slave transfer dropped a conditional which meant that we
started waiting for completion of all transfers, not just those that the
controller asked for.  This caused hangs and massive delays on platforms
that don't need the core delay.  Re-add the delay to fix this.

Fixes: 810923f3bf (spi: Deal with slaves that return from transfer_one() unfinished)
Reported-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-15 16:08:32 -08:00
Lubomir Rintel 810923f3bf
spi: Deal with slaves that return from transfer_one() unfinished
Some drivers, such as spi-pxa2xx return from the transfer_one callback
immediately, idicating that the transfer will be finished asynchronously.

Normally, spi_transfer_one_message() synchronously waits for the
transfer to finish with wait_for_completion_timeout(). For slaves, we
don't want the transaction to time out as it can complete in a long time
in future. Use wait_for_completion_interruptible() instead.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-13 10:01:23 -08:00
Mark Brown 7b9734dbc5
Merge remote-tracking branch 'spi/topic/of' into spi-next 2018-10-21 17:00:17 +01:00
Mark Brown 4b51c747e4
Merge branch 'spi-4.20' into spi-next 2018-10-21 17:00:14 +01:00
Phil Elwell 25972d0c33
spi: Make GPIO CSs honour the SPI_NO_CS flag
The SPI configuration state includes an SPI_NO_CS flag that disables
all CS line manipulation, for applications that want to manage their
own chip selects. However, this flag is ignored by the GPIO CS code
in the SPI framework.

Correct this omission with a trivial patch.

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-10-12 18:47:28 +02:00
Trent Piepho 5039563e7c
spi: Add driver_override SPI device attribute
This attribute works the same was as the identically named attribute
for PCI, AMBA, and platform devices.  For reference, see:

commit 3cf3857134 ("ARM: 8256/1: driver coamba: add device binding
path 'driver_override'")
commit 3d713e0e38 ("driver core: platform: add device binding path
'driver_override'")
commit 782a985d7a ("PCI: Introduce new device binding path using
pci_dev.driver_override")

If the name of a driver is written to this attribute, then the device
will bind to the named driver and only the named driver.

The device will bind to the driver even if the driver does not list the
device in its id table.  This behavior is different than the driver's
bind attribute, which only allows binding to devices that are listed as
supported by the driver.

It can be used to bind a generic driver, like spidev, to a device.

Signed-off-by: Trent Piepho <tpiepho@impinj.com>
Reviewed-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Tested-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-10-10 13:40:45 +01:00
Marco Felsch 5f143af750
spi: make OF helper available for others
The of_find_spi_device_by_node() helper function is useful for other
modules too. Export the funciton as GPL like all other spi helper
functions and make it available if CONFIG_OF is enabled, because it isn't
related to the CONFIG_OF_DYNAMIC context. Finally add a stub if
CONFIG_OF isn't enabled, so others must not care about it.

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-09-27 23:36:03 +01:00
Marco Felsch b445bfcb90
spi: switch to SPDX license identifier
Use the appropriate SPDX license identifier and drop the previous
license text.

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-09-27 23:30:48 +01:00
David Lechner 71388b2156
spi: always use software fallback for SPI_CS_WORD when using cs_gio
This modifies the condition for using the software fallback
implementation for SPI_CS_WORD when the SPI controller is using a GPIO
for the CS line. When using a GPIO for CS, the hardware implementation
won't work, so we just enable the software fallback globally in this
case.

Signed-off-by: David Lechner <david@lechnology.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-09-18 10:40:32 -07:00
David Lechner cbaa62e009
spi: add software implementation for SPI_CS_WORD
This adds a default software implementation for the SPI_CS_WORD flag for
controllers that don't have such a feature.

The SPI_CS_WORD flag indicates that the CS line should be toggled
between each word sent, not just between each transfer. The
implementation works by using existing functions to split transfers into
one-word-sized transfers and sets the cs_change bit for each of the
new transfers.

Signed-off-by: David Lechner <david@lechnology.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-09-17 14:14:18 -07:00
Geert Uytterhoeven 04b2d03a75
spi: Fix double IDR allocation with DT aliases
If the SPI bus number is provided by a DT alias, idr_alloc() is called
twice, leading to:

    WARNING: CPU: 1 PID: 1 at drivers/spi/spi.c:2179 spi_register_controller+0x11c/0x5d8
    couldn't get idr

Fix this by moving the handling of fixed SPI bus numbers up, before the
DT handling code fills in ctlr->bus_num.

Fixes: 1a4327fbf4 ("spi: fix IDR collision on systems with both fixed and dynamic SPI bus numbers")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-08-28 20:46:27 +01:00
Kirill Kapranov 1a4327fbf4
spi: fix IDR collision on systems with both fixed and dynamic SPI bus numbers
On systems where some controllers get a dynamic ID assigned and some have
a fixed number (e.g. from ACPI tables), the current implementation might
run into an IDR collision: in case of a fixed bus number is gotten by a
driver (but not marked busy in IDR tree) and a driver with dynamic bus
number gets the same ID and predictably fails.

Fix this by means of checking-in fixed IDsin IDR as far as dynamic ones
at the moment of the controller registration.

Fixes: 9b61e30221 (spi: Pick spi bus number from Linux idr or spi alias)
Signed-off-by: Kirill Kapranov <kirill.kapranov@compulab.co.il>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
2018-08-15 15:44:07 +01:00
Kees Cook a86854d0c5 treewide: devm_kzalloc() -> devm_kcalloc()
The devm_kzalloc() function has a 2-factor argument form, devm_kcalloc().
This patch replaces cases of:

        devm_kzalloc(handle, a * b, gfp)

with:
        devm_kcalloc(handle, a * b, gfp)

as well as handling cases of:

        devm_kzalloc(handle, a * b * c, gfp)

with:

        devm_kzalloc(handle, array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        devm_kcalloc(handle, array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        devm_kzalloc(handle, 4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

Some manual whitespace fixes were needed in this patch, as Coccinelle
really liked to write "=devm_kcalloc..." instead of "= devm_kcalloc...".

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
expression HANDLE;
type TYPE;
expression THING, E;
@@

(
  devm_kzalloc(HANDLE,
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  devm_kzalloc(HANDLE,
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression HANDLE;
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  devm_kzalloc(HANDLE,
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
expression HANDLE;
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
expression HANDLE;
identifier SIZE, COUNT;
@@

- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression HANDLE;
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression HANDLE;
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
expression HANDLE;
identifier STRIDE, SIZE, COUNT;
@@

(
  devm_kzalloc(HANDLE,
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression HANDLE;
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  devm_kzalloc(HANDLE, C1 * C2 * C3, ...)
|
  devm_kzalloc(HANDLE,
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  devm_kzalloc(HANDLE,
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression HANDLE;
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  devm_kzalloc(HANDLE, sizeof(THING) * C2, ...)
|
  devm_kzalloc(HANDLE, sizeof(TYPE) * C2, ...)
|
  devm_kzalloc(HANDLE, C1 * C2 * C3, ...)
|
  devm_kzalloc(HANDLE, C1 * C2, ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	(E1) * E2
+	E1, E2
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00