spi: spidev: Follow renaming of SPI "master" to "controller"

In commit 8caab75fd2c2 ("spi: Generalize SPI "master" to "controller"")
some functions and struct members were renamed. To not break all drivers
compatibility macros were provided.

To be able to remove these compatibility macros push the renaming into
this driver.

Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/15ebfdf58a6590962bdd51b49b2e85a69b3bf443.1707324794.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: make spidev_class constant

Now that the driver core allows for struct class to be in read-only
memory, we should make all 'class' structures declared at build time
placing them into read-only memory, instead of having to be dynamically
allocated at runtime.

Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/2023100639-celtic-herbs-66be@gregkh
Signed-off-by: Mark Brown <broonie@kernel.org>

spidev: Simplify SPI_IOC_RD_MODE* cases in spidev_ioctl()

The temporary variable tmp is not used outside of the
SPI_IOC_RD_MODE* cases, hence we can optimize its use.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Link: https://lore.kernel.org/r/20230824162209.2890440-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spidev: Switch to use spi_get_csgpiod()

spidev_ioctl() checks if there is an SPI chip select is driven by GPIO.
Instead of current code, we can call spi_get_csgpiod().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Link: https://lore.kernel.org/r/20230824162209.2890440-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spidev: Decrease indentation level in spidev_ioctl() SPI_IOC_RD_MODE*

Instead of defining a local controller variable inside an indented
block, move the definition to the top of spidev_ioctl() and reuse
it in the SPI_IOC_RD_MODE* and SPI_IOC_WR_MODE* cases.

This drops unneeded indentation and reduces amount of LoCs.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Link: https://lore.kernel.org/r/20230824162209.2890440-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/spi: use ARCH_DMA_MINALIGN instead of ARCH_KMALLOC_MINALIGN

ARCH_DMA_MINALIGN represents the minimum (static) alignment for safe DMA
operations while ARCH_KMALLOC_MINALIGN is the minimum kmalloc() objects
alignment.

Link: https://lkml.kernel.org/r/20230612153201.554742-9-catalin.marinas@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Mark Brown <broonie@kernel.org>
Tested-by: Isaac J. Manjarres <isaacmanjarres@google.com>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jerry Snitselaar <jsnitsel@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

spi: spidev: add two new spi mode bits

Allow userspace to set SPI_MOSI_IDLE_LOW and the SPI_3WIRE_HIZ mode bit
using the SPI_IOC_WR_MODE32 ioctl.

Signed-off-by: Boerge Struempfel <boerge.struempfel@gmail.com>
Link: https://lore.kernel.org/r/20230530141641.1155691-4-boerge.struempfel@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

driver core: class: remove module * from class_create()

The module pointer in class_create() never actually did anything, and it
shouldn't have been requred to be set as a parameter even if it did
something. So just remove it and fix up all callers of the function in
the kernel tree at the same time.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20230313181843.1207845-4-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spi: Replace all spi->chip_select and spi->cs_gpiod references with function call

Supporting multi-cs in spi drivers would require the chip_select & cs_gpiod
members of struct spi_device to be an array. But changing the type of these
members to array would break the spi driver functionality. To make the
transition smoother introduced four new APIs to get/set the
spi->chip_select & spi->cs_gpiod and replaced all spi->chip_select and
spi->cs_gpiod references with get or set API calls.
While adding multi-cs support in further patches the chip_select & cs_gpiod
members of the spi_device structure would be converted to arrays & the
"idx" parameter of the APIs would be used as array index i.e.,
spi->chip_select[idx] & spi->cs_gpiod[idx] respectively.

Signed-off-by: Amit Kumar Mahapatra <amit.kumar-mahapatra@amd.com>
Acked-by: Heiko Stuebner <heiko@sntech.de> # Rockchip drivers
Reviewed-by: Michal Simek <michal.simek@amd.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org> # Aspeed driver
Reviewed-by: Dhruva Gole <d-gole@ti.com> # SPI Cadence QSPI
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com> # spi-stm32-qspi
Acked-by: William Zhang <william.zhang@broadcom.com> # bcm63xx-hsspi driver
Reviewed-by: Serge Semin <fancer.lancer@gmail.com> # DW SSI part
Link: https://lore.kernel.org/r/167847070432.26.15076794204368669839@mailman-core.alsa-project.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Fix double unlock in spidev_sync()

This unlocks twice due to a merge issue.

Fixes: 35bba23e6732 ("Merge remote-tracking branch 'spi/for-6.2' into spi-6.2")
Signed-off-by: Dan Carpenter <error27@gmail.com>
Link: https://lore.kernel.org/r/Y+ETCk7XKfAy8yWQ@kili
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: order compatibles alphabetically

Bring some order to reduce possibilities of conflicts.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230120075651.153763-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: remove debug messages that access spidev->spi without locking

The two debug messages in spidev_open() dereference spidev->spi without
taking the lock and without checking if it's not null. This can lead to
a crash. Drop the messages as they're not needed - the user-space will
get informed about ENOMEM with the syscall return value.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://lore.kernel.org/r/20230106100719.196243-2-brgl@bgdev.pl
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: fix a race condition when accessing spidev->spi

There's a spinlock in place that is taken in file_operations callbacks
whenever we check if spidev->spi is still alive (not null). It's also
taken when spidev->spi is set to NULL in remove().

This however doesn't protect the code against driver unbind event while
one of the syscalls is still in progress. To that end we need a lock taken
continuously as long as we may still access spidev->spi. As both the file
ops and the remove callback are never called from interrupt context, we
can replace the spinlock with a mutex.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://lore.kernel.org/r/20230106100719.196243-1-brgl@bgdev.pl
Signed-off-by: Mark Brown <broonie@kernel.org>

spidev: Add Silicon Labs SI3210 device compatible

Add compatible string for Silicon Labs SI3210 device.

Signed-off-by: Vincent Tremblay <vincent@vtremblay.dev>
Link: https://lore.kernel.org/r/20221227141011.111410-2-vincent@vtremblay.dev
Signed-off-by: Mark Brown <broonie@kernel.org>

spidev: Add Silicon Labs EM3581 device compatible

Add compatible string for Silicon Labs EM3581 device.

Signed-off-by: Vincent Tremblay <vincent@vtremblay.dev>
Link: https://lore.kernel.org/r/20221227023550.569547-2-vincent@vtremblay.dev
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: fix a recursive locking error

When calling spidev_message() from the one of the ioctl() callbacks, the
spi_lock is already taken. When we then end up calling spidev_sync(), we
get the following splat:

[ 214.047619]
[ 214.049198] ============================================
[ 214.054533] WARNING: possible recursive locking detected
[ 214.059858] 6.2.0-rc3-0.0.0-devel+git.97ec4d559d93 #1 Not tainted
[ 214.065969] --------------------------------------------
[ 214.071290] spidev_test/1454 is trying to acquire lock:
[ 214.076530] c4925dbc (&spidev->spi_lock){+.+.}-{3:3}, at: spidev_ioctl+0x8e0/0xab8
[ 214.084164]
[ 214.084164] but task is already holding lock:
[ 214.090007] c4925dbc (&spidev->spi_lock){+.+.}-{3:3}, at: spidev_ioctl+0x44/0xab8
[ 214.097537]
[ 214.097537] other info that might help us debug this:
[ 214.104075] Possible unsafe locking scenario:
[ 214.104075]
[ 214.110004] CPU0
[ 214.112461] ----
[ 214.114916] lock(&spidev->spi_lock);
[ 214.118687] lock(&spidev->spi_lock);
[ 214.122457]
[ 214.122457] *** DEADLOCK ***
[ 214.122457]
[ 214.128386] May be due to missing lock nesting notation
[ 214.128386]
[ 214.135183] 2 locks held by spidev_test/1454:
[ 214.139553] #0: c4925dbc (&spidev->spi_lock){+.+.}-{3:3}, at: spidev_ioctl+0x44/0xab8
[ 214.147524] #1: c4925e14 (&spidev->buf_lock){+.+.}-{3:3}, at: spidev_ioctl+0x70/0xab8
[ 214.155493]
[ 214.155493] stack backtrace:
[ 214.159861] CPU: 0 PID: 1454 Comm: spidev_test Not tainted 6.2.0-rc3-0.0.0-devel+git.97ec4d559d93 #1
[ 214.169012] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
[ 214.175555] unwind_backtrace from show_stack+0x10/0x14
[ 214.180819] show_stack from dump_stack_lvl+0x60/0x90
[ 214.185900] dump_stack_lvl from __lock_acquire+0x874/0x2858
[ 214.191584] __lock_acquire from lock_acquire+0xfc/0x378
[ 214.196918] lock_acquire from __mutex_lock+0x9c/0x8a8
[ 214.202083] __mutex_lock from mutex_lock_nested+0x1c/0x24
[ 214.207597] mutex_lock_nested from spidev_ioctl+0x8e0/0xab8
[ 214.213284] spidev_ioctl from sys_ioctl+0x4d0/0xe2c
[ 214.218277] sys_ioctl from ret_fast_syscall+0x0/0x1c
[ 214.223351] Exception stack(0xe75cdfa8 to 0xe75cdff0)
[ 214.228422] dfa0: 00000000 00001000 00000003 40206b00 bee266e8 bee266e0
[ 214.236617] dfc0: 00000000 00001000 006a71a0 00000036 004c0040 004bfd18 00000000 00000003
[ 214.244809] dfe0: 00000036 bee266c8 b6f16dc5 b6e8e5f6

Fix it by introducing an unlocked variant of spidev_sync() and calling it
from spidev_message() while other users who don't check the spidev->spi's
existence keep on using the locking flavor.

Reported-by: Francesco Dolcini <francesco@dolcini.it>
Fixes: 1f4d2dd45b6e ("spi: spidev: fix a race condition when accessing spidev->spi")
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Tested-by: Max Krummenacher <max.krummenacher@toradex.com>
Link: https://lore.kernel.org/r/20230116144149.305560-1-brgl@bgdev.pl
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: remove debug messages that access spidev->spi without locking

The two debug messages in spidev_open() dereference spidev->spi without
taking the lock and without checking if it's not null. This can lead to
a crash. Drop the messages as they're not needed - the user-space will
get informed about ENOMEM with the syscall return value.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://lore.kernel.org/r/20230106100719.196243-2-brgl@bgdev.pl
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: fix a race condition when accessing spidev->spi

There's a spinlock in place that is taken in file_operations callbacks
whenever we check if spidev->spi is still alive (not null). It's also
taken when spidev->spi is set to NULL in remove().

This however doesn't protect the code against driver unbind event while
one of the syscalls is still in progress. To that end we need a lock taken
continuously as long as we may still access spidev->spi. As both the file
ops and the remove callback are never called from interrupt context, we
can replace the spinlock with a mutex.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://lore.kernel.org/r/20230106100719.196243-1-brgl@bgdev.pl
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: mask SPI_CS_HIGH in SPI_IOC_RD_MODE

Commit f3186dd87669 ("spi: Optionally use GPIO descriptors for CS GPIOs")
has changed the user-space interface so that bogus SPI_CS_HIGH started
to appear in the mask returned by SPI_IOC_RD_MODE even for active-low CS
pins. Commit 138c9c32f090
("spi: spidev: Fix CS polarity if GPIO descriptors are used") fixed only
SPI_IOC_WR_MODE part of the problem. Let's fix SPI_IOC_RD_MODE
symmetrically.

Test case:

#include <sys/ioctl.h>
#include <fcntl.h>
#include <linux/spi/spidev.h>

int main(int argc, char **argv)
{
char modew = SPI_CPHA;
char moder;
int f = open("/dev/spidev0.0", O_RDWR);

if (f < 0)
return 1;

ioctl(f, SPI_IOC_WR_MODE, &modew);
ioctl(f, SPI_IOC_RD_MODE, &moder);

return moder == modew ? 0 : 2;
}

Fixes: f3186dd87669 ("spi: Optionally use GPIO descriptors for CS GPIOs")
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Link: https://lore.kernel.org/r/20221130162927.539512-1-alexander.sverdlin@siemens.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: add SPI_RX_CPHA_FLIP

Allow userspace to set SPI_RX_CPHA_FLIP mode bit using the
SPI_IOC_WR_MODE32 ioctl.

Signed-off-by: Baruch Siach <baruch.siach@siklu.com>
Link: https://lore.kernel.org/r/6ae31ad24f8252418878b21a8759a04b78726dac.1649702729.git.baruch@tkos.co.il
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: replace usage of found with dedicated list iterator variable

To move the list iterator variable into the list_for_each_entry_*()
macro in the future it should be avoided to use the list iterator
variable after the loop body.

To *never* use the list iterator variable after the loop it was
concluded to use a separate iterator variable instead of a
found boolean [1].

This removes the need to use a found variable and simply checking if
the variable was set, can determine if the break/goto was hit.

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Link: https://lore.kernel.org/r/20220324072534.63420-1-jakobkoschel@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Replace OF specific code by device property API

Instead of calling the OF specific APIs, use device property ones.

It also prevents misusing PRP0001 in ACPI when trying to instantiate
spidev directly. We only support special SPI test devices there.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220323140215.2568-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Replace ACPI specific code by device_get_match_data()

Instead of calling the ACPI specific APIs, use device_get_match_data().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220323140215.2568-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Convert BUILD_BUG_ON() to static_assert()

static_assert() is a preferred method to fail build when the certain
constraints are not met. Convert BUILD_BUG_ON() to static_assert().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220323140215.2568-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: make remove callback a void function

The value returned by an spi driver's remove function is mostly ignored.
(Only an error message is printed if the value is non-zero that the
error is ignored.)

So change the prototype of the remove function to return no value. This
way driver authors are not tempted to assume that passing an error to
the upper layer is a good idea. All drivers are adapted accordingly.
There is no intended change of behaviour, all callbacks were prepared to
return 0 before.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Claudius Heine <ch@denx.de>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC
Acked-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Acked-by: Łukasz Stelmach <l.stelmach@samsung.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20220123175201.34839-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: prevent spidev->speed_hz from being zero

A zero value for spi->max_speed_hz or spidev->speed_hz does not make
sense and trying to set that can lead to divide by zero crashes in
a some of the drivers.

drivers/spi/spi-s3c64xx.c:874 s3c64xx_spi_setup() error: potential divide by zero bug '/ spi->max_speed_hz'.
drivers/spi/spi-fsl-dspi.c:613 hz_to_spi_baud() error: potential divide by zero bug '/ speed_hz'.
drivers/spi/spi-xlp.c:146 xlp_spi_setup() error: potential divide by zero bug '/ (spi->max_speed_hz)'.
drivers/spi/spi-orion.c:162 orion_spi_baudrate_set() error: potential divide by zero bug '/ speed'.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20220125065202.GA8807@kili
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Make probe to fail early if a spidev compatible is used

Some Device Trees don't use a real device name in the compatible string
for SPI devices nodes, abusing the fact that the spidev driver name is
used to match as a fallback when a SPI device ID table is not defined.

But since commit 6840615f85f6 ("spi: spidev: Add SPI ID table") a table
for SPI device IDs was added to the driver breaking the assumption that
these DTs were relying on.

There has been a warning message for some time since commit 956b200a846e
("spi: spidev: Warn loudly if instantiated from DT as "spidev""), making
quite clear that this case is not really supported by the spidev driver.

Since these devices won't match anyways after the mentioned commit, there
is no point to continue if an spidev compatible is used. Let's just make
the driver probe to fail early.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20211109225920.1158920-1-javierm@redhat.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Use SPI_MODE_USER_MASK instead of casting

Currently the 16-bit mode is what being used in user space.
However assuming that is not fully correct. Instead we should
use the respective mask, i.e. SPI_MODE_USER_MASK, which
precisely defines what bits are available for user space apps.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211122175245.84691-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Add SPI ID table

Currently autoloading for SPI devices does not use the DT ID table, it uses
SPI modalises. Supporting OF modalises is going to be difficult if not
impractical, an attempt was made but has been reverted, so ensure that
module autoloading works for this driver by adding an id_table listing the
SPI IDs for everything.

Fixes: 96c8395e2166 ("spi: Revert modalias changes")
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210923170023.1683-1-broonie@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

misc: gehc-achc: new driver

General Electric Healthcare's PPD has a secondary processor from
NXP's Kinetis K20 series. That device has two SPI chip selects:

The main interface's behaviour depends on the loaded firmware
and is currently unused.

The secondary interface can be used to update the firmware using
EzPort protocol. This is implemented by this driver using the
kernel's firmware API. The firmware is being flashed into
non-volatile flash memory, so it is enough to flash it once
and not on every boot. Flashing will wear the flash memory
(it has a life time of at least 10k programming cycles). At
the same time only occasional FW updates are expected (like e.g.
a BIOS update). Thus the firmware update is triggered via sysfs
instead of doing it in the driver's probe routine like many
other drivers.

Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Link: https://lore.kernel.org/r/20210802172309.164365-4-sebastian.reichel@collabora.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spi: spidev: Use SPI_MODE_X_MASK

Use SPI_MODE_X_MASK instead of open coded variant.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210510131217.49357-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spidev: Add Micron SPI NOR Authenta device compatible

Add compatible string for Micron SPI NOR Authenta device.

Signed-off-by: Shivamurthy Shastri <sshivamurthy@micron.com>
Link: https://lore.kernel.org/r/20210419204015.1769-1-sshivamurthy@micron.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spidev: Add cisco device compatible

Add compatible string for Cisco device present on the Cisco Petra
platform.

Signed-off-by: Daniel Walker <danielwa@cisco.com>
Cc: xe-linux-external@cisco.com
Link: https://lore.kernel.org/r/20210121231237.30664-2-danielwa@cisco.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Remove redundant initialization of variable status

In spidev_read() and spidev_write(), the variable status is being
initialized with a value that is never read and it is being updated
later with a new value. The initialization is redundant and can be
removed.

Signed-off-by: Jay Fang <f.fangjian@huawei.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/1599631704-53232-1-git-send-email-f.fangjian@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Align buffers for DMA

Simply copying all xfers from userspace into one bounce buffer causes
alignment problems if the SPI controller uses DMA.

Ensure that all transfer data blocks within the rx and tx bounce buffers
are aligned for DMA (according to ARCH_KMALLOC_MINALIGN).

Alignment may increase the usage of the bounce buffers. In some cases,
the buffers may need to be increased using the "bufsiz" module
parameter.

Signed-off-by: Christian Eggers <ceggers@arri.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200728100832.24788-1-ceggers@arri.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: fix a potential use-after-free in spidev_release()

If an spi device is unbounded from the driver before the release
process, there will be an NULL pointer reference when it's
referenced in spi_slave_abort().

Fix it by checking it's already freed before reference.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@gmail.com>
Link: https://lore.kernel.org/r/20200618032125.4650-2-zhenzhong.duan@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: fix a race between spidev_release and spidev_remove

Imagine below scene, spidev is referenced after it's freed.

spidev_release() spidev_remove()
...
spin_lock_irq(&spidev->spi_lock);
spidev->spi = NULL;
spin_unlock_irq(&spidev->spi_lock);
mutex_lock(&device_list_lock);
dofree = (spidev->spi == NULL);
if (dofree)
kfree(spidev);
mutex_unlock(&device_list_lock);
mutex_lock(&device_list_lock);
list_del(&spidev->device_entry);
device_destroy(spidev_class, spidev->devt);
clear_bit(MINOR(spidev->devt), minors);
if (spidev->users == 0)
kfree(spidev);
mutex_unlock(&device_list_lock);

Fix it by resetting spidev->spi in device_list_lock's protection.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@gmail.com>
Link: https://lore.kernel.org/r/20200618032125.4650-1-zhenzhong.duan@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Add support for Octal mode data transfers

Include the flags for Octal mode data transfers in the mask, so
userspace can set them.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200416101835.14573-2-geert+renesas@glider.be
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: fix speed setting message

The message of max device speed setting is shown when
an error in spi_setup() occurs.
Instead, it should be shown when the setup call succeeds.

Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com>
Link: https://lore.kernel.org/r/20200229161841.89144-3-oleksandr.suvorov@toradex.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: fix a debug message value

The debug message in spidev_message() can show wrong xfer speed.
It happens if the initial (came from DT) and set with ioctl call spidev
speeds are different (spidev->speed_hz != spi->max_speed_hz) and one
sends a message with ioctl call and the field of speed is uninitialized
(u_tmp->speed_hz == 0).

In this case the kernel shows the spi->max_speed_hz value instead of
correct spidev->speed_hz.
...
set the max speed with an ioctl call:
[ 1227.702714] spidev spi0.0: setup mode 0, 32 bits/w, 20000000 Hz max --> 0
(real speed sets to 20000000Hz)
send a message with an ioctl call:
[ 1227.731801] spidev spi0.0: xfer len 4096 tx 32bits 0 usec 10000000Hz
(debug message shows 10000000Hz that is the original max speed of this
spidev came from DT)
...

Fix the data source for the debug message.

Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com>
Link: https://lore.kernel.org/r/20200229161841.89144-2-oleksandr.suvorov@toradex.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Fix CS polarity if GPIO descriptors are used

Commit f3186dd87669 ("spi: Optionally use GPIO descriptors for CS GPIOs")
amended of_spi_parse_dt() to always set SPI_CS_HIGH for SPI slaves whose
Chip Select is defined by a "cs-gpios" devicetree property.

This change broke userspace applications which issue an SPI_IOC_WR_MODE
ioctl() to an spidev: Chip Select polarity will be incorrect unless the
application is changed to set SPI_CS_HIGH. And once changed, it will be
incompatible with kernels not containing the commit.

Fix by setting SPI_CS_HIGH in spidev_ioctl() (under the same conditions
as in of_spi_parse_dt()).

Fixes: f3186dd87669 ("spi: Optionally use GPIO descriptors for CS GPIOs")
Reported-by: Simon Han <z.han@kunbus.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/fca3ba7cdc930cd36854666ceac4fbcf01b89028.1582027457.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org # v5.1+

spi: spidev: use new `delay` field for spi transfers

The `delay` field has type `struct spi_delay`.
This allows users to specify nano-second or clock-cycle delays (if needed).

Converting to use `delay` is straightforward: it's just assigning the
value to `delay.value` and hard-coding the `delay.unit` to
`SPI_DELAY_UNIT_USECS`.

This keeps the uapi for spidev un-changed. Changing it can be part of
another changeset and discussion.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20190926105147.7839-14-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: use new `word_delay` field for spi transfers

The `word_delay` field had it's type changed to `struct spi_delay`.
This allows users to specify nano-second or clock-cycle delays (if needed).

Converting to use `word_delay` is straightforward: it's just assigning the
value to `word_delay.value` and hard-coding the `word_delay.unit` to
`SPI_DELAY_UNIT_USECS`

This keeps the uapi for spidev un-changed. Changing it can be part of
another changeset and discussion.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20190926105147.7839-7-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: Add call to spi_slave_abort() function when spidev driver is released

This change is necessary for spidev devices (e.g. /dev/spidev3.0) working
in the slave mode (like NXP's dspi driver for Vybrid SoC).

When SPI HW works in this mode - the master is responsible for providing
CS and CLK signals. However, when some fault happens - like for example
distortion on SPI lines - the SPI Linux driver needs a chance to recover
from this abnormal situation and prepare itself for next (correct)
transmission.

This change doesn't pose any threat on drivers working in master mode as
spi_slave_abort() function checks if SPI slave mode is supported.

Signed-off-by: Lukasz Majewski <lukma@denx.de>
Link: https://lore.kernel.org/r/20190924110547.14770-2-lukma@denx.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Reported-by: kbuild test robot <lkp@intel.com>
Link: https://lore.kernel.org/r/20190925091143.15468-2-lukma@denx.de
Signed-off-by: Mark Brown <broonie@kernel.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157

Based on 3 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [kishon] [vijay] [abraham]
[i] [kishon]@[ti] [com] this program is distributed in the hope that
it will be useful but without any warranty without even the implied
warranty of merchantability or fitness for a particular purpose see
the gnu general public license for more details

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [graeme] [gregory]
[gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
[kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
[hk] [hemahk]@[ti] [com] this program is distributed in the hope
that it will be useful but without any warranty without even the
implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1105 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spidev: Add M53Menlo CPLD compatible

Add compatible string for Menlosystems CPLD present on the M53Menlo
board. This CPLD is used to communicate with various custom sensors.

Signed-off-by: Marek Vasut <marex@denx.de>
To: linux-spi@vger.kernel.org
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Add dhcom-board to compatibility list

Prepare to use devices on the external SPI interface
on a DH electronics Development Board.

Signed-off-by: Christoph Niedermaier <cniedermaier@dh-electronics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

*: convert stream-like files from nonseekable_open -> stream_open

Using scripts/coccinelle/api/stream_open.cocci added in 10dce8af3422
("fs: stream_open - opener for stream-like files so that read and write
can run simultaneously without deadlock"), search and convert to
stream_open all in-kernel nonseekable_open users for which read and
write actually do not depend on ppos and where there is no other methods
in file_operations which assume @offset access.

I've verified each generated change manually - that it is correct to convert -
and each other nonseekable_open instance left - that it is either not correct
to convert there, or that it is not converted due to current stream_open.cocci
limitations. The script also does not convert files that should be valid to
convert, but that currently have .llseek = noop_llseek or generic_file_llseek
for unknown reason despite file being opened with nonseekable_open (e.g.
drivers/input/mousedev.c)

Among cases converted 14 were potentially vulnerable to read vs write deadlock
(see details in 10dce8af3422):

drivers/char/pcmcia/cm4000_cs.c:1685:7-23: ERROR: cm4000_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix.
drivers/gnss/core.c:45:1-17: ERROR: gnss_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix.
drivers/hid/uhid.c:635:1-17: ERROR: uhid_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix.
drivers/infiniband/core/user_mad.c:988:1-17: ERROR: umad_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix.
drivers/input/evdev.c:527:1-17: ERROR: evdev_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix.
drivers/input/misc/uinput.c:401:1-17: ERROR: uinput_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix.
drivers/isdn/capi/capi.c:963:8-24: ERROR: capi_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix.
drivers/leds/uleds.c:77:1-17: ERROR: uleds_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix.
drivers/media/rc/lirc_dev.c:198:1-17: ERROR: lirc_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix.
drivers/s390/char/fs3270.c:488:1-17: ERROR: fs3270_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix.
drivers/usb/misc/ldusb.c:310:1-17: ERROR: ld_usb_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix.
drivers/xen/evtchn.c:667:8-24: ERROR: evtchn_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix.
net/batman-adv/icmp_socket.c:80:1-17: ERROR: batadv_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix.
net/rfkill/core.c:1146:8-24: ERROR: rfkill_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix.

and the rest were just safe to convert to stream_open because their read and
write do not use ppos at all and corresponding file_operations do not
have methods that assume @offset file access(*):

arch/powerpc/platforms/52xx/mpc52xx_gpt.c:631:8-24: WARNING: mpc52xx_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_ibox_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_ibox_stat_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_mbox_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_mbox_stat_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_wbox_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_wbox_stat_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
arch/um/drivers/harddog_kern.c:88:8-24: WARNING: harddog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
arch/x86/kernel/cpu/microcode/core.c:430:33-49: WARNING: microcode_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/char/ds1620.c:215:8-24: WARNING: ds1620_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/char/dtlk.c:301:1-17: WARNING: dtlk_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open.
drivers/char/ipmi/ipmi_watchdog.c:840:9-25: WARNING: ipmi_wdog_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open.
drivers/char/pcmcia/scr24x_cs.c:95:8-24: WARNING: scr24x_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open.
drivers/char/tb0219.c:246:9-25: WARNING: tb0219_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open.
drivers/firewire/nosy.c:306:8-24: WARNING: nosy_ops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/hwmon/fschmd.c:840:8-24: WARNING: watchdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/hwmon/w83793.c:1344:8-24: WARNING: watchdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/infiniband/core/ucma.c:1747:8-24: WARNING: ucma_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/infiniband/core/ucm.c:1178:8-24: WARNING: ucm_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/infiniband/core/uverbs_main.c:1086:8-24: WARNING: uverbs_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/input/joydev.c:282:1-17: WARNING: joydev_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/pci/switch/switchtec.c:393:1-17: WARNING: switchtec_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open.
drivers/platform/chrome/cros_ec_debugfs.c:135:8-24: WARNING: cros_ec_console_log_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/rtc/rtc-ds1374.c:470:9-25: WARNING: ds1374_wdt_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open.
drivers/rtc/rtc-m41t80.c:805:9-25: WARNING: wdt_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open.
drivers/s390/char/tape_char.c:293:2-18: WARNING: tape_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open.
drivers/s390/char/zcore.c:194:8-24: WARNING: zcore_reipl_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/s390/crypto/zcrypt_api.c:528:8-24: WARNING: zcrypt_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open.
drivers/spi/spidev.c:594:1-17: WARNING: spidev_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open.
drivers/staging/pi433/pi433_if.c:974:1-17: WARNING: pi433_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/acquirewdt.c:203:8-24: WARNING: acq_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/advantechwdt.c:202:8-24: WARNING: advwdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/alim1535_wdt.c:252:8-24: WARNING: ali_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/alim7101_wdt.c:217:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/ar7_wdt.c:166:8-24: WARNING: ar7_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/at91rm9200_wdt.c:113:8-24: WARNING: at91wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/ath79_wdt.c:135:8-24: WARNING: ath79_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/bcm63xx_wdt.c:119:8-24: WARNING: bcm63xx_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/cpu5wdt.c:143:8-24: WARNING: cpu5wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/cpwd.c:397:8-24: WARNING: cpwd_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/eurotechwdt.c:319:8-24: WARNING: eurwdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/f71808e_wdt.c:528:8-24: WARNING: watchdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/gef_wdt.c:232:8-24: WARNING: gef_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/geodewdt.c:95:8-24: WARNING: geodewdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/ib700wdt.c:241:8-24: WARNING: ibwdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/ibmasr.c:326:8-24: WARNING: asr_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/indydog.c:80:8-24: WARNING: indydog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/intel_scu_watchdog.c:307:8-24: WARNING: intel_scu_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/iop_wdt.c:104:8-24: WARNING: iop_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/it8712f_wdt.c:330:8-24: WARNING: it8712f_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/ixp4xx_wdt.c:68:8-24: WARNING: ixp4xx_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/ks8695_wdt.c:145:8-24: WARNING: ks8695wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/m54xx_wdt.c:88:8-24: WARNING: m54xx_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/machzwd.c:336:8-24: WARNING: zf_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/mixcomwd.c:153:8-24: WARNING: mixcomwd_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/mtx-1_wdt.c:121:8-24: WARNING: mtx1_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/mv64x60_wdt.c:136:8-24: WARNING: mv64x60_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/nuc900_wdt.c:134:8-24: WARNING: nuc900wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/nv_tco.c:164:8-24: WARNING: nv_tco_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/pc87413_wdt.c:289:8-24: WARNING: pc87413_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/pcwd.c:698:8-24: WARNING: pcwd_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/pcwd.c:737:8-24: WARNING: pcwd_temp_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/pcwd_pci.c:581:8-24: WARNING: pcipcwd_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/pcwd_pci.c:623:8-24: WARNING: pcipcwd_temp_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/pcwd_usb.c:488:8-24: WARNING: usb_pcwd_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/pcwd_usb.c:527:8-24: WARNING: usb_pcwd_temperature_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/pika_wdt.c:121:8-24: WARNING: pikawdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/pnx833x_wdt.c:119:8-24: WARNING: pnx833x_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/rc32434_wdt.c:153:8-24: WARNING: rc32434_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/rdc321x_wdt.c:145:8-24: WARNING: rdc321x_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/riowd.c:79:1-17: WARNING: riowd_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/sa1100_wdt.c:62:8-24: WARNING: sa1100dog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/sbc60xxwdt.c:211:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/sbc7240_wdt.c:139:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/sbc8360.c:274:8-24: WARNING: sbc8360_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/sbc_epx_c3.c:81:8-24: WARNING: epx_c3_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/sbc_fitpc2_wdt.c:78:8-24: WARNING: fitpc2_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/sb_wdog.c:108:1-17: WARNING: sbwdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/sc1200wdt.c:181:8-24: WARNING: sc1200wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/sc520_wdt.c:261:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/sch311x_wdt.c:319:8-24: WARNING: sch311x_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/scx200_wdt.c:105:8-24: WARNING: scx200_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/smsc37b787_wdt.c:369:8-24: WARNING: wb_smsc_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/w83877f_wdt.c:227:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/w83977f_wdt.c:301:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/wafer5823wdt.c:200:8-24: WARNING: wafwdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/watchdog_dev.c:828:8-24: WARNING: watchdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/wdrtas.c:379:8-24: WARNING: wdrtas_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/wdrtas.c:445:8-24: WARNING: wdrtas_temp_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/wdt285.c:104:1-17: WARNING: watchdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/wdt977.c:276:8-24: WARNING: wdt977_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/wdt.c:424:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/wdt.c:484:8-24: WARNING: wdt_temp_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/wdt_pci.c:464:8-24: WARNING: wdtpci_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open.
drivers/watchdog/wdt_pci.c:527:8-24: WARNING: wdtpci_temp_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
net/batman-adv/log.c:105:1-17: WARNING: batadv_log_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
sound/core/control.c:57:7-23: WARNING: snd_ctl_f_ops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.
sound/core/rawmidi.c:385:7-23: WARNING: snd_rawmidi_f_ops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open.
sound/core/seq/seq_clientmgr.c:310:7-23: WARNING: snd_seq_f_ops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open.
sound/core/timer.c:1428:7-23: WARNING: snd_timer_f_ops: .read() has stream semantic; safe to change nonseekable_open -> stream_open.

One can also recheck/review the patch via generating it with explanation comments included via

$ make coccicheck MODE=patch COCCI=scripts/coccinelle/api/stream_open.cocci SPFLAGS="-D explain"

(*) This second group also contains cases with read/write deadlocks that
stream_open.cocci don't yet detect, but which are still valid to convert to
stream_open since ppos is not used. For example drivers/pci/switch/switchtec.c
calls wait_for_completion_interruptible() in its .read, but stream_open.cocci
currently detects only "wait_event*" as blocking.

Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yongzhi Pan <panyongzhi@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Tejun Heo <tj@kernel.org>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Nikolaus Rath <Nikolaus@rath.org>
Cc: Han-Wen Nienhuys <hanwen@google.com>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James R. Van Zandt" <jrv@vanzandt.mv.com>
Cc: Corey Minyard <minyard@acm.org>
Cc: Harald Welte <laforge@gnumonks.org>
Acked-by: Lubomir Rintel <lkundrak@v3.sk> [scr24x_cs]
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Johan Hovold <johan@kernel.org>
Cc: David Herrmann <dh.herrmann@googlemail.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc: Jean Delvare <jdelvare@suse.com>
Acked-by: Guenter Roeck <linux@roeck-us.net> [watchdog/* hwmon/*]
Cc: Rudolf Marek <r.marek@assembler.cz>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Kurt Schwemmer <kurt.schwemmer@microsemi.com>
Acked-by: Logan Gunthorpe <logang@deltatee.com> [drivers/pci/switch/switchtec]
Acked-by: Bjorn Helgaas <bhelgaas@google.com> [drivers/pci/switch/switchtec]
Cc: Benson Leung <bleung@chromium.org>
Acked-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> [platform/chrome]
Cc: Alessandro Zummo <a.zummo@towertech.it>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com> [rtc/*]
Cc: Mark Brown <broonie@kernel.org>
Cc: Wim Van Sebroeck <wim@linux-watchdog.org>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Zwane Mwaikambo <zwanem@gmail.com>
Cc: Marek Lindner <mareklindner@neomailbox.ch>
Cc: Simon Wunderlich <sw@simonwunderlich.de>
Cc: Antonio Quartulli <a@unstable.cc>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>

spi: spidev: Enable control of inter-word delays

Commit b7bb367afa4b added support for inserting delays in between
individual words within a single SPI transaction. This makes it
accessible from userspace.

WARNING: This delay is silently ignored unless the SPI controller
implements extra support for it. This is similar to how the in-kernel
users handle the other existing property, spi_transfer->word_delay.

Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Fix OF tree warning logic

spidev will make a big fuss if a device tree node binds a device by
using "spidev" as the node's compatible property.

However, the logic for this isn't looking for "spidev" in the
compatible, but rather checking that the device is NOT compatible with
spidev's list of devices.

This causes a false positive if a device not named "rohm,dh2228fv", etc.
binds to spidev, even if a means other than putting "spidev" in the
device tree was used. E.g., the sysfs driver_override attribute.

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>

spidev: Enable the Liebherr's BK4 board to work with spidev driver

With this commit the DSPI driver on the BK4 board can be used for SPI
transmission managed from user space (via /dev/spidev0.0).

Example usage/testing:
insmod ./spi-fsl-dspi.ko
./spidev_test -D /dev/spidev0.0 -s 3000000 -v -H -b 8 -p "\xCC\x11\x22\x74"

Signed-off-by: Lukasz Majewski <lukma@denx.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

spidev: quit messing with access_ok()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

spi: spidev: use memdup_user

Use memdup_user() helper instead of open-coding to simplify the code.

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: remove unused completion

This removes an unused completion from spidev_sync.

It was introduced in

commit 25d5cb4b0375e ("spi: remove some spidev oops-on-rmmod paths")

and it was no longer used after:

commit 98d6f47958001 ("spi: spidev: use spi_sync instead of spi_async")

Signed-off-by: Seraphime Kirkovski (Haapie) <kirkseraph@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Add sx1301 to device tree compatibility list

Add entry for the semtech sx1301 baseband processor implementing a LoRa
concentrator IP.
At this time this chip requires an spidev userspace driver.

Signed-off-by: Ben Whitten <ben.whitten@lairdtech.com>
Signed-off-by: Steve deRosier <derosier@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Add device to spidev device tree compatibility list

Entries are needed in the spidev ID list to configure configure it from a
device tree. Add entry for the following device:
- "ge,achc" : GE Healthcare USB Management Controller

The USB Management Controller does not expose USB to the host, but acts as
an offload engine, communicating with specific USB based data acquisition
devices which are connected to it, extracting the required data and
providing it to the host via other methods. SPI is used as an out-of-band
configuration channel.

Signed-off-by: Fabien Lahoudere <fabien.lahoudere@collabora.co.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Add ACPI probing support

Some IoT and maker software stacks are using spidev to perform raw access
to the SPI bus instead of relying existing drivers provided by the kernel.
They then implement their own "drivers" in userspace on top of the spidev
raw interface. This is far from being an ideal solution but we do not want
to prevent using mainline Linux in these devices.

Now, it turns out that Windows has similar SPI devices than spidev which
allow raw access on the SPI bus to userspace programs as described in the
link below:

https://msdn.microsoft.com/windows/hardware/drivers/spb/spi-tests-in-mitt

These SPI test devices are also meant to be used during development and
testing.

In order to allow usage of spidev for development and testing in Linux, add
those same ACPI IDs to the spidev driver (which is Linux counterpart of the
Windows SPI test devices), but complain loudly so that users know it is not
good idea to use it in production systems. Instead they should be using
proper drivers for peripherals connected to the SPI bus.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Hold spi_lock over all defererences of spi in release()

We use the spi_lock spinlock to protect against races between the device
being removed and file operations on the spidev. This means that in the
removal path all references to the device need to be done under lock as
in removal we dropping references to the device.

Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Use "%u" to format __u32

On 64-bit with CONFIG_SPI_DEBUG=y and #define VERBOSE:

drivers/spi/spidev.c:287:3: warning: format '%zd' expects argument of type 'signed size_t', but argument 4 has type '__u32' [-Wformat=]

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: Drop owner assignment from spi_drivers

An spi_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: fix possible NULL dereference

During the last close we are freeing spidev if spidev->spi is NULL, but
just before checking if spidev->spi is NULL we are dereferencing it.
Lets add a check there to avoid the NULL dereference.

Fixes: 9169051617df ("spi: spidev: Don't mangle max_speed_hz in underlying spi device")
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: fix inconsistent indenting

Fix inconsistent indenting in spidev_open, no functional change.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Fix typo

Fix the typo in "compatible".

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: add compatible value for LTC2488

Since spidev is no more allowed to use in DT and is really loudly warned about
it I'd like to add this compatible value.
(Geert Uytterhoeven wrote: "Add the compatible value for your device to the
spidev_dt_ids[] array in drivers/spi/spidev.c.")

Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Remove unneeded variable

Remove unneeded variable used to store return value.

The semantic patch that makes this change is available
in scripts/coccinelle/misc/returnvar.cocci.

More information about semantic patching is available at
http://coccinelle.lip6.fr/

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: use spi_sync instead of spi_async

This has the benefit that the "optimization" of the framework in regards
to spi_sync will also benefit spidev users directly and allow running
spi transfers without a necessary context-switch to message-pump.

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Warn loudly if instantiated from DT as "spidev"

Since spidev is a detail of how Linux controls a device rather than a
description of the hardware in the system we should never have a node
described as "spidev" in DT, any SPI device could be a spidev so this
is just not a useful description.

In order to help prevent users from writing such device trees generate a
warning if spidev is instantiated as a DT node without an ID in the match
table.

Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: fix possible arithmetic overflow for multi-transfer message

`spidev_message()` sums the lengths of the individual SPI transfers to
determine the overall SPI message length. It restricts the total
length, returning an error if too long, but it does not check for
arithmetic overflow. For example, if the SPI message consisted of two
transfers and the first has a length of 10 and the second has a length
of (__u32)(-1), the total length would be seen as 9, even though the
second transfer is actually very long. If the second transfer specifies
a null `rx_buf` and a non-null `tx_buf`, the `copy_from_user()` could
overrun the spidev's pre-allocated tx buffer before it reaches an
invalid user memory address. Fix it by checking that neither the total
nor the individual transfer lengths exceed the maximum allowed value.

Thanks to Dan Carpenter for reporting the potential integer overflow.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: only use up TX/RX bounce buffer space when needed

This patch changes the way space is reserved in spidev's pre-allocated
TX and RX bounce buffers to avoid wasting space in the buffers for an
SPI message consisting of multiple, half-duplex transfers in different
directions.

Background:

spidev data structures have separate, pre-allocated TX and RX bounce
buffers (`spidev->tx_buffer` and `spidev->rx_buffer`) of fixed size
(`bufsiz`). The `SPI_IOC_MESSAGE(N)` ioctl processing uses a kernel
copy of the N `struct spi_ioc_transfer` elements copied from the
userspace ioctl arg pointer. In these elements: `.len` is the length of
transfer in bytes; `.rx_buf` is either a userspace pointer to a buffer
to copy the RX data to or is set to 0 to discard the data; and `.tx_buf`
is either a userspace pointer to TX data supplied by the user or is set
to 0 to transmit zeros for this transfer.

`spidev_message()` uses the array of N `struct spi_ioc_transfer`
elements to construct a kernel SPI message consisting of a `struct
spi_message` containing a linked list (allocated as an array) of N
`struct spi_transfer` elements. This involves iterating through the
`struct spi_ioc_transfer` and `struct spi_transfer` elements (variables
`u_tmp` and `k_tmp` respectively). Before the first iteration,
variables `tx_buf` and `rx_buf` point to the start of the TX and RX
bounce buffers `spidev->tx_buffer` and `spidev->rx_buffer` and variable
`total` is set to 0. These variables keep track of the next available
space in the bounce buffers and the total length of the SPI message.
Each iteration checks that there is enough room left in the buffers for
the transfer. If `u_tmp->rx_buf` is non-zero, `k_tmp->rx_buf` is set to
`rx_buf`, otherwise it remains set to NULL. If `u_tmp->tx_buf` is
non-zero, `k_tmp->tx_buf` is set to `tx_buf` and the userspace TX data
copied there, otherwise it remains set to NULL. The variables `total`,
`rx_buf` and `tx_buf` are advanced by the length of the transfer.

The "problem":

While iterating through the transfers, the local bounce buffer "free
space" pointer variables `tx_buf` and `rx_buf` are always advanced by
the length of the transfer. If `u_tmp->rx_buf` is 0 (so `k_tmp->rx_buf`
is NULL), then `rx_buf` is advanced unnecessarily and that part of
`spidev->rx_buffer` is wasted. Similarly, if `u_tmp->tx_buf` is 0 (so
`k_tmp->tx_buf` is NULL), part of `spidev->tx_buffer` is wasted.

What this patch does:

To avoid wasting space unnecessarily in the RX bounce buffer, only
advance `rx_buf` by the transfer length if `u_tmp->rx_buf` is non-zero.
Similarly, to avoid wasting space unnecessarily in the TX bounce buffer,
only advance `tx_buf` if `u_tmp->tx_buf is non-zero. To avoid pointer
subtraction, use new variables `rx_total` and `tx_total` to keep track
of the amount of space allocated in each of the bounce buffers. If
these exceed the available space, a `-EMSGSIZE` error will be returned.

Limit the total length of the transfers (tracked by variable `total`) to
`INT_MAX` instead of `bufsiz`, returning an `-EMSGSIZE` error if
exceeded. The total length is returned by `spidev_message()` on success
and we want that to be non-negative. The message size limits for the
`SPI_IOC_MESSAGE(N)` ioctl are now as follows:

(a) total length of transfers is <= INTMAX;
(b) total length of transfers with non-NULL rx_buf is <= bufsiz;
(c) total length of transfers with non-NULL tx_buf is <= bufsiz.

Some transfers may have NULL rx_buf and NULL tx_buf.

If the transfer is completed successfully by the SPI core,
`spidev_message()` iterates through the transfers to copy any RX data
from the bounce buffer back to userspace on those transfers where
`u_tmp->rx_buf` is non-zero. The variable `rx_buf` is again used to
keep track of the corresponding positions in the bounce buffer. Now it
is only advanced for those transfers that use the RX bounce buffer.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Convert buf pointers for 32-bit compat SPI_IOC_MESSAGE(n)

The SPI_IOC_MESSAGE(n) ioctl commands' argument points to an array of n
struct spi_ioc_transfer elements. The spidev's compat_ioctl handler
just converts this pointer and passes it on to the unlocked_ioctl
handler to process it.

The tx_buf and rx_buf members of struct spi_ioc_transfer are of type
__u64 and hold pointer values. A 32-bit userspace application running
in a 64-bit kernel might not have widened the 32-bit pointers correctly
for the kernel. The application might have sign-extended the pointer to
when the kernel expects it to be zero-extended, or vice versa, leading
to an -EFAULT being returned by spidev_message() if the widened pointer
is invalid.

Handle the SPI_IOC_MESSAGE(n) ioctl commands specially in the
compat_ioctl handler, calling new function spidev_compat_ioctl_message()
to handle them. This processes them in the same way as the
unlocked_ioctl handler except that it uses compat_ptr() to convert the
tx_buf and rx_buf members of each struct spi_ioc_transfer element.

To save code, factor out part of the unlocked_ioctl handler into a new
function spidev_get_ioc_message(). This checks the ioctl command code
is a valid SPI_IOC_MESSAGE(n), determines n and copies the array of n
struct spi_ioc_transfer elements from userspace into dynamically
allocated memory, returning either a pointer to the memory, an
ERR_PTR(-err) value, or NULL (for SPI_IOC_MESSAGE(0)).

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: Remove FSF mailing addresses

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Don't mangle max_speed_hz in underlying spi device

Currently spidev allows callers to set the default speed by overriding the
max_speed_hz in the underlying device. This achieves the immediate goal but
is not what devices expect and can easily lead to userspace trying to set
unsupported speeds and succeeding, apart from anything else drivers can't
set a limit on the speed using max_speed_hz as they'd expect and any other
devices on the bus will be affected.

Instead store the default speed in the spidev struct and fill this in on
each transfer.

Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Use separate TX and RX bounce buffers

By using separate TX and RX bounce buffers, we avoid potential cache
flush and invalidation sequence issue that may be encountered when a
single bounce buffer is shared between TX and RX

Signed-off-by: Ray Jui <rjui@broadcom.com>
Reviewed-by: JD (Jiandong) Zheng <jdzheng@broadcom.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: spidev: Add support for Dual/Quad SPI Transfers

Add support for Dual/Quad SPI Transfers to the spidev API.
As this uses SPI mode bits that don't fit in a single byte, two new
ioctls (SPI_IOC_RD_MODE32 and SPI_IOC_WR_MODE32) are introduced.

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: spidev: Restore all SPI mode flags on ioctl failure

In commit f477b7fb13df2b843997559ff34e87d054ba6538 ("spi: DUAL and QUAD
support"), spi_device.mode was enlarged from 8 to 16 bits.

However, the spidev code still only saved 8 bits of data. If a spidev
SPI_IOC_WR_MODE or SPI_IOC_WR_LSB_FIRST request failed, only the lower 8
bits of the SPI mode were restored, inadvertently clearing the upper 8
bits, possibly disabling Quad or Dual SPI transfers for the device.

Save up to 32 bits to fix this.

For SPI_IOC_WR_MODE this is probably not so important, as it doesn't allow
setting Quad or Dual mode anyway, but SPI_IOC_WR_LSB_FIRST is used to just
set or clear a single bit.

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: spidev: Fix checkpatch issue

Fix the following checkpatch warnings.

WARNING: Use #include <linux/uaccess.h> instead of <asm/uaccess.h>
WARNING: braces {} are not necessary for any arm of this statement

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

spi: spidev: remove unnecessary spi_set_drvdata()

The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

PTR_RET is now PTR_ERR_OR_ZERO(): Replace most.

Sweep of the simple cases.

Cc: netdev@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

spi/spidev: Use PTR_RET function

Replaced calls to IS_ERR and PTR_ERR with PTR_RET function.
Patch found using coccinelle.

Signed-off-by: Alexandru Gheorghiu <gheorghiuandru@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi: Remove HOTPLUG section attributes

CONFIG_HOTPLUG is going away as an option. As result the __dev*
markings will be going away.

Remove use of __devinit, __devexit_p, __devinitdata, __devinitconst,
and __devexit.

Bill Pemberton has done most of the legwork on this series. I've used
his script to purge the attributes from the drivers/gpio tree.

Reported-by: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi: spidev: Add Rohm DH2228FV DAC compatible string

Since we don't have a driver for it yet, use spidev instead.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi: spidev: Add device tree bindings

This will allow to probe spidev from device tree by adding the
compatible string of each device to this array.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

spi: reorganize drivers

Sort the SPI makefile and enforce the naming convention spi_*.c for
spi drivers.

This change also rolls the contents of atmel_spi.h into the .c file
since there is only one user of that particular include file.

v2: - Use 'spi-' prefix instead of 'spi_' to match what seems to be
be the predominant pattern for subsystem prefixes.
- Clean up filenames in Kconfig and header comment blocks

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>

spi/spidev: Add 32 bit compat ioctl()

Add the compat_ioctl for operations on /dev/spi* so that 32 bit
userspace applications can access SPI. As far as I can see all data
structure are already prepared for that, so no additional conversion has
to be done.

My use case is MIPS with N32 userspace ABI and toolchain, and that was
also the platform where I tested it successfully (Cavium Octeon).

Signed-off-by: Bernhard Walle <walle@corscience.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

tree-wide: fix comment/printk typos

"gadget", "through", "command", "maintain", "maintain", "controller", "address",
"between", "initiali[zs]e", "instead", "function", "select", "already",
"equal", "access", "management", "hierarchy", "registration", "interest",
"relative", "memory", "offset", "already",

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

llseek: automatically add .llseek fop

All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.

The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.

New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.

The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.

Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.

Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.

===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}

@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}

@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}

@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}

@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}

@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}

@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};

@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};

@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};

@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};

@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};

// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};

@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};

// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};

// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};

// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};

@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};

// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////

@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};

@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};

@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};

@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>

spidev: add proper section markers

The driver already uses __devexit_p() in the structure, but looks like
actual __dev{init,exit} markings were forgotten.

The spidev_spi driver also needs renaming to include a "_driver" suffix to
avoid section mismatch warnings.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spidev: use DECLARE_BITMAP instead of declaring the array

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spi: fix spidev compilation failure when VERBOSE is defined

When VERBOSE is defined in the spidev module, the compilation
will throw an error on 'spi' not being defined:

CC [M] drivers/spi/spidev.o
drivers/spi/spidev.c: In function 'spidev_message':
drivers/spi/spidev.c:266: error: 'spi' undeclared (first use in this function)
drivers/spi/spidev.c:266: error: (Each undeclared identifier is reported only once
drivers/spi/spidev.c:266: error: for each function it appears in.)

instead of using spi-> we should actually use spidev->spi.
This patch fixes the build failure.

Signed-off-by: Florian Fainelli <ffainelli@freebox.fr>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

spidev: fix double "of of" in comment

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

spi: Remove BKL from spidev_open

The BKL was added there with the big pushdown. Remove it as the code
is serialized already.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <20091010153349.318535932@linutronix.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>

const: constify remaining file_operations

[akpm@linux-foundation.org: fix KVM]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

spi: prefix modalias with "spi:"

This makes it consistent with other buses (platform, i2c, vio, ...). I'm
not sure why we use the prefixes, but there must be a reason.

This was easy enough to do it, and I did it.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: Samuel Ortiz <sameo@openedhand.com>
Cc: "John W. Linville" <linville@tuxdriver.com>
Acked-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

spi: new spi->mode bits

Add two new spi_device.mode bits to accomodate more protocol options, and
pass them through to usermode drivers:

* SPI_NO_CS ... a second 3-wire variant, where the chipselect
line is removed instead of a data line; transfers are still
full duplex.

This obviously has STRONG protocol implications since the
chipselect transitions can't be used to synchronize state
transitions with the SPI master.

* SPI_READY ... defines open drain signal that's pulled low
to pause the clock. This defines a 5-wire variant (normal
4-wire SPI plus READY) and two 4-wire variants (READY plus
each of the 3-wire flavors).

Such hardware flow control can be a big win. There are ADC
converters and flash chips that expose READY signals, but not
many host controllers support it today.

The spi_bitbang code should be changed to use SPI_NO_CS instead of its
current nonportable hack. That's a mode most hardware can easily support
(unlike SPI_READY).

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: "Paulraj, Sandeep" <s-paulraj@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

spi: avoid spidev crash when device is removed

I saw a kernel oops in spidev_remove() when a spidev device was registered
and I unloaded the SPI master driver:

Unable to handle kernel paging request for data at address 0x00000004
Faulting instruction address: 0xc01c0c50
Oops: Kernel access of bad area, sig: 11 [#1]
CDSPR
Modules linked in: spi_ppc4xx(-)
NIP: c01c0c50 LR: c01bf9e4 CTR: c01c0c34
REGS: cec89c30 TRAP: 0300 Not tainted (2.6.27.3izt)
MSR: 00021000 <ME> CR: 24000228 XER: 20000007
DEAR: 00000004, ESR: 00800000
TASK = cf889040[2070] 'rmmod' THREAD: cec88000
GPR00: 00000000 cec89ce0 cf889040 cec8e000 00000004 cec8e000 ffffffff 00000000
GPR08: 0000001c c0336380 00000000 c01c0c34 00000001 1001a338 100e0000 100df49c
GPR16: 100b54c0 100df49c 100ddd20 100f05a8 100b5340 100efd68 00000000 00000000
GPR24: 100ec008 100f0428 c0327788 c0327794 cec8e0ac cec8e000 c0336380 00000000
NIP [c01c0c50] spidev_remove+0x1c/0xe4
LR [c01bf9e4] spi_drv_remove+0x2c/0x3c
Call Trace:
[cec89d00] [c01bf9e4] spi_drv_remove+0x2c/0x3c
[cec89d10] [c01859a0] __device_release_driver+0x78/0xb4
[cec89d20] [c0185ab0] device_release_driver+0x28/0x44
[cec89d40] [c0184be8] bus_remove_device+0xac/0xd8
[cec89d60] [c0183094] device_del+0x100/0x194
[cec89d80] [c0183140] device_unregister+0x18/0x30
[cec89da0] [c01bf30c] __unregister+0x20/0x34
[cec89db0] [c0182778] device_for_each_child+0x38/0x74
[cec89de0] [c01bf2d0] spi_unregister_master+0x28/0x44
[cec89e00] [c01bfeac] spi_bitbang_stop+0x1c/0x58
[cec89e20] [d908a5e0] spi_ppc4xx_of_remove+0x24/0x7c [spi_ppc4xx]
[...]

IMHO a call to spi_set_drvdata() is missing in spidev_probe(). The patch
below helped.

Signed-off-by: Wolfgang Ocker <weo@reccoware.de>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

device create: misc: convert device_create_drvdata to device_create

Now that device_create() has been audited, rename things back to the
original call to be sane.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

spidev: BKL removal

Another step to removing ->ioctl and to removing the BKL

[dbrownell@users.sourceforge.net: take final step; BKL not needed]
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

device create: spi: convert device_create to device_create_drvdata

Switch over to use the shiny new device_create_drvdata() call
instead of the original device_create() calls, so this continues
to work after device_create() is removed.

Note that this driver never had the race which motivated removing
the original call; it locked correctly.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

spi: fix the read path in spidev

This got broken by the recent "fix rmmod $spi_driver while spidev-user is
active". I tested the rmmod & write path but didn't check the read path.
I am sorry. The read logic changed and spidev_sync_read() +
spidev_sync_write() do not return zero on success anymore but the number
of bytes that has been transfered over the bus. This patch changes the
logic and copy_to_user() gets called again.

The write path returns the number of bytes which are written to the
underlying device what may be less than the requested size. This patch
makes the same change to the read path or else we request a read of 20
bytes, get 10, don't call copy to user and report to the user that we read
10 bytes.

[akpm@linux-foundation.org: remove test of known-to-be-zero local]
Signed-off-by: Sebastian Siewior <bigeasy@linutronix.de>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

spidev: BKL pushdown

Add the BKL to spidev_open(), even though the existing locking looks
adequate.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>

spi: fix refcount-related spidev oops-on-rmmod

This addresses other oopsing paths in "spidev" by changing how it manages
refcounting. It decouples the lifecycle of the per-device data from the
class device (not just the spi device):

- Use class_{create,destroy} not class_{register,unregister}.
- Use device_{create,destroy} not device_{register,unregister}.
- Free the per-device data only when TWO conditions are true:
* Driver is unbound from underlying SPI device, and
* Device is no longer open (new)

Also, spi_{get,set}_drvdata not dev_{get,set}_drvdata for simpler code.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Sebastian Siewior <bigeasy@tglx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

spi: remove some spidev oops-on-rmmod paths

Somehow the spidev code forgot to include a critical mechanism: when the
underlying device is removed (e.g. spi_master rmmod), open file
descriptors must be prevented from issuing new I/O requests to that
device. On penalty of the oopsing reported by Sebastian Siewior
<bigeasy@tglx.de> ...

This is a partial fix, adding handshaking between the lower level (SPI
messaging) and the file operations using the spi_dev. (It also fixes an
issue where reads and writes didn't return the number of bytes sent or
received.)

There's still a refcounting issue to be addressed (separately).

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Reported-by: Sebastian Siewior <bigeasy@tglx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fix abuses of ptrdiff_t

Use of ptrdiff_t in places like

- if (!access_ok(VERIFY_WRITE, u_tmp->rx_buf, u_tmp->len))
+ if (!access_ok(VERIFY_WRITE, (u8 __user *)
+ (ptrdiff_t) u_tmp->rx_buf,
+ u_tmp->len))

is wrong; for one thing, it's a bad C (it's what uintptr_t is for; in general
we are not even promised that ptrdiff_t is large enough to hold a pointer,
just enough to hold a difference between two pointers within the same object).
For another, it confuses the fsck out of sparse.

Use unsigned long or uintptr_t instead. There are several places misusing
ptrdiff_t; fixed.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

spidev warning fix

Git rid of "warning: passing arg 2 of `access_ok' makes pointer from integer
without a cast" reported on SH ... most architectures use macros in that
test, SH uses inlined functions.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

spidev supports more communications modes

The spidev driver doesn't currently expose all SPI communications modes to
userspace. This passes them all through to the driver.

Two of them are potentially troublesome, in the sense that they could cause
hardware conflicts on shared busses. It might be appropriate to add some
privilege checks for for those modes.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

spidev compiler warning gone

Get rid of annoying GCC warning on 32-bit platforms.

drivers/spi/spidev.c: In function 'spidev_message':
drivers/spi/spidev.c:184: warning: cast to pointer from integer of different size
drivers/spi/spidev.c:216: warning: cast to pointer from integer of different size

The trick is to add an extra cast using "ptrdiff_t" to convert the u64 to
the correct size integer, and only then casting it into a "void *" pointer.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

spi: potential memleak in spidev_ioctl

'ioc' should be deallocated if __copy_from_user fails (found by Coverity
- CID 1644).

Signed-off-by: Florin Malita <fmalita@gmail.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

spi/spidev: check message size before copying

Message size needs to be checked before copying, or bad things could
happen.

Signed-off-by: Domen Puncer <domen.puncer@telargo.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

spi: fix spidev for >sizeof(long)/32 devices

find_first_zero_bit accepts number of bits, not longs.

Signed-off-by: Domen Puncer <domen.puncer@telargo.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

/dev/spidevB.C interface

Add a filesystem API for <linux/spi/spi.h> stack. The initial version of
this interface is purely synchronous.

dbrownell@users.sourceforge.net:

Cleaned up, bugfixed; much simplified; added preliminary documentation.

Works with mdev given CONFIG_SYSFS_DEPRECATED; and presumably udev.

Updated SPI_IOC_MESSAGE ioctl to full spi_message semantics, supporting
groups of one or more transfers (each of which may be full duplex if
desired).

This is marked as EXPERIMENTAL with an explicit disclaimer that the API
(notably the ioctls) is subject to change.

Signed-off-by: Andrea Paterniani <a.paterniani@swapp-eng.it>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>