linux.git/drivers/gpio, branch v6.9-rc4

gpio: cdev: fix missed label sanitizing in debounce_setup()

2024-04-04T16:57:08+00:00

When adding sanitization of the label, the path through
edge_detector_setup() that leads to debounce_setup() was overlooked.
A request taking this path does not allocate a new label and the
request label is freed twice when the request is released, resulting
in memory corruption.

Add label sanitization to debounce_setup().

Cc: stable@vger.kernel.org
Fixes: b34490879baa ("gpio: cdev: sanitize the label before requesting the interrupt")
Signed-off-by: Kent Gibson 
[Bartosz: rebased on top of the fix for empty GPIO labels]
Co-developed-by: Bartosz Golaszewski 
Signed-off-by: Bartosz Golaszewski

gpio: cdev: check for NULL labels when sanitizing them for irqs

2024-04-04T14:57:52+00:00

We need to take into account that a line's consumer label may be NULL
and not try to kstrdup() it in that case but rather pass the NULL
pointer up the stack to the interrupt request function.

To that end: let make_irq_label() return NULL as a valid return value
and use ERR_PTR() instead to signal an allocation failure to callers.

Cc: stable@vger.kernel.org
Fixes: b34490879baa ("gpio: cdev: sanitize the label before requesting the interrupt")
Reported-by: Linux Kernel Functional Testing 
Closes: https://lore.kernel.org/lkml/20240402093534.212283-1-naresh.kamboju@linaro.org/
Signed-off-by: Bartosz Golaszewski 
Tested-by: Anders Roxell

gpiolib: Fix triggering "kobject: 'gpiochipX' is not initialized, yet" kobject_get() errors

2024-04-03T11:04:32+00:00

When a gpiochip gets added by loading a module, then another driver may
be waiting for that gpiochip to load on the deferred-probe list.

If the deferred-probe for the consumer of gpiochip then triggers between
the gpiodev_add_to_list_unlocked() calls which makes gpio_device_find()
see the chip and the gpiochip_setup_dev() later then gpio_device_find()
does a kobject_get() on an uninitialized kobject since the kobject is
initialized by gpiochip_setup_dev() calling device_initialize():

 arizona spi-10WM5102:00: cannot find GPIO chip arizona, deferring
 arizona spi-10WM5102:00: cannot find GPIO chip arizona, deferring
 ------------[ cut here ]------------
 kobject: 'gpiochip5' (00000000241466f2): is not initialized, yet kobject_get() is being called.
 WARNING: CPU: 3 PID: 42 at lib/kobject.c:640 kobject_get+0x43/0x70
 Call Trace:
  kobject_get
  gpio_device_find
  gpiod_find_and_request
  gpiod_get
  snd_byt_wm5102_mc_probe

Not only is the device not initialized yet, but when the gpio-device is
added to the list things like the irqchip also have not been initialized
yet.

So gpio_device_find() should really ignore the gpio-device until
gpiochip_add_data_with_key() is fully done. Add a device_is_registered()
check to gpio_device_find() to ignore gpio-devices on the list which are
not yet fully initialized.

Fixes: aab5c6f20023 ("gpio: set device type for GPIO chips")
Suggested-by: Bartosz Golaszewski 
Signed-off-by: Hans de Goede 
Reviewed-by: Andy Shevchenko 
[Bartosz: fix a typo in commit message]
Signed-off-by: Bartosz Golaszewski

gpiolib: Fix debug messaging in gpiod_find_and_request()

2024-03-26T11:50:50+00:00

When consolidating GPIO lookups in ACPI code, the debug messaging
had been reworked that the user may see

  [   13.401147] (NULL device *): using ACPI '\_SB.LEDS.led-0' for '(null)' GPIO lookup
  [   13.401378] gpio gpiochip0: Persistence not supported for GPIO 40
  [   13.401402] gpio-40 (?): no flags found for (null)

instead of

  [   14.182962] gpio gpiochip0: Persistence not supported for GPIO 40
  [   14.182994] gpio-40 (?): no flags found for gpios

The '(null)' parts are less informative and likely scare the users.
Replace them by '(default)' which can point out to the default connection
IDs, such as 'gpios'.

While at it, amend other places where con_id is used in the messages.

Reported-by: Ferry Toth 
Fixes: 8eb1f71e7acc ("gpiolib: consolidate GPIO lookups")
Suggested-by: Dmitry Torokhov 
Tested-by: Ferry Toth 
Signed-off-by: Andy Shevchenko 
Signed-off-by: Bartosz Golaszewski

gpio: cdev: sanitize the label before requesting the interrupt

2024-03-26T11:43:35+00:00

When an interrupt is requested, a procfs directory is created under
"/proc/irq//" where  is the string passed to one of
the request_irq() variants.

What follows is that the string must not contain the "/" character or
the procfs mkdir operation will fail. We don't have such constraints for
GPIO consumer labels which are used verbatim as interrupt labels for
GPIO irqs. We must therefore sanitize the consumer string before
requesting the interrupt.

Let's replace all "/" with ":".

Cc: stable@vger.kernel.org
Reported-by: Stefan Wahren 
Closes: https://lore.kernel.org/linux-gpio/39fe95cb-aa83-4b8b-8cab-63947a726754@gmx.net/
Signed-off-by: Bartosz Golaszewski 
Reviewed-by: Kent Gibson

Merge tag 'pinctrl-v6.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl

2024-03-14T17:22:26+00:00

Pull pin control updates from Linus Walleij:
 "No core changes this time around.

  New drivers:

   - New driver for Renesas R8A779H0 also known as R-Car V4M.

   - New driver for the Awinic AW9523/B I2C GPIO expander. I found this
     living out-of-tree in OpenWrt as an upstream attempt had stalled on
     the finishing line, so I picked it up and finished the job.

  Improvements:

   - The Nomadik pin control driver was for years re-used out of tree
     for the ST STA chips, and now the IP was re-used in a MIPS
     automotive SoC called MobilEyeq5, so it has been split in pin
     control and GPIO drivers so the latter can be reused by MobilEyeq5.
     (Along with a long list of cleanups)

   - A lot of overall cleanup and tidying up"

* tag 'pinctrl-v6.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (87 commits)
  drivers/gpio/nomadik: move dummy nmk_gpio_dbg_show_one() to header
  gpio: nomadik: remove BUG_ON() in nmk_gpio_populate_chip()
  dt-bindings: pinctrl: qcom: update compatible name for match with driver
  pinctrl: aw9523: Make the driver tristate
  pinctrl: nomadik: fix dereference of error pointer
  gpio: nomadik: Back out some managed resources
  pinctrl: aw9523: Add proper terminator
  pinctrl: core: comment that pinctrl_add_gpio_range() is deprecated
  pinctrl: pinmux: Suppress error message for -EPROBE_DEFER
  pinctrl: Add driver for Awinic AW9523/B I2C GPIO Expander
  dt-bindings: pinctrl: Add bindings for Awinic AW9523/AW9523B
  gpio: nomadik: Finish conversion to use firmware node APIs
  gpio: nomadik: fix Kconfig dependencies inbetween pinctrl & GPIO
  pinctrl: da9062: Add OF table
  dt-bindings: pinctrl: at91: add sam9x7
  pinctrl: ocelot: remove redundant assignment to variable ret
  gpio: nomadik: grab optional reset control and deassert it at probe
  gpio: nomadik: support mobileye,eyeq5-gpio
  gpio: nomadik: handle variadic GPIO count
  gpio: nomadik: support shared GPIO IRQs
  ...

Merge tag 'gpio-updates-for-v6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux

2024-03-13T18:14:55+00:00

Pull gpio updates from Bartosz Golaszewski:
 "The biggest feature is the locking overhaul. Up until now the
  synchronization in the GPIO subsystem was broken. There was a single
  spinlock "protecting" multiple data structures but doing it wrong (as
  evidenced by several places where it would be released when a sleeping
  function was called and then reacquired without checking the protected
  state).

  We tried to use an RW semaphore before but the main issue with GPIO is
  that we have drivers implementing the interfaces in both sleeping and
  non-sleeping ways as well as user-facing interfaces that can be called
  both from process as well as atomic contexts. Both ends converge in
  the same code paths that can use neither spinlocks nor mutexes. The
  only reasonable way out is to use SRCU and go mostly lockless. To that
  end: we add several SRCU structs in relevant places and use them to
  assure consistency between API calls together with atomic reads and
  writes of GPIO descriptor flags where it makes sense.

  This code has spent several weeks in next and has received several
  fixes in the first week or two after which it stabilized nicely. The
  GPIO subsystem is now resilient to providers being suddenly unbound.
  We managed to also remove the existing character device RW semaphore
  and the obsolete global spinlock.

  Other than the locking rework we have one new driver (for Chromebook
  EC), much appreciated documentation improvements from Kent and the
  regular driver improvements, DT-bindings updates and GPIOLIB core
  tweaks.

  Serialization rework:
   - use SRCU to serialize access to the global GPIO device list, to
     GPIO device structs themselves and to GPIO descriptors
   - make the GPIO subsystem resilient to the GPIO providers being
     unbound while the API calls are in progress
   - don't dereference the SRCU-protected chip pointer if the
     information we need can be obtained from the GPIO device structure
   - move some of the information contained in struct gpio_chip to
     struct gpio_device to further reduce the need to dereference the
     former
   - pass the GPIO device struct instead of the GPIO chip to sysfs
     callback to, again, reduce the need for accessing the latter
   - get GPIO descriptors from the GPIO device, not from the chip for
     the same reason
   - allow for mostly lockless operation of the GPIO driver API: assure
     consistency with SRCU and atomic operations
   - remove the global GPIO spinlock
   - remove the character device RW semaphore

  Core GPIOLIB:
   - constify pointers in GPIO API where applicable
   - unify the GPIO counting APIs for ACPI and OF
   - provide a macro for iterating over all GPIOs, not only the ones
     that are requested
   - remove leftover typedefs
   - pass the consumer device to GPIO core in
     devm_fwnode_gpiod_get_index() for improved logging
   - constify the GPIO bus type
   - don't warn about removing GPIO chips with descriptors still held by
     users as we can now handle this situation gracefully
   - remove unused logging helpers
   - unexport functions that are only used internally in the GPIO
     subsystem
   - set the device type (assign the relevant struct device_type) for
     GPIO devices

  New drivers:
   - add the ChromeOS EC GPIO driver

  Driver improvements:
   - allow building gpio-vf610 with COMPILE_TEST as well as disabling it
     in menuconfig (before it was always built for i.MX cofigs)
   - count the number of EICs using the device properties instead of
     hard-coding it in gpio-eic-sprd
   - improve the device naming, extend the debugfs output and add
     lockdep asserts to gpio-sim

  DT bindings:
   - document the 'label' property for gpio-pca9570
   - convert aspeed,ast2400-gpio bindings to DT schema
   - disallow unevaluated properties for gpio-mvebu
   - document a new model in renesas,rcar-gpio

  Documentation:
   - improve the character device kerneldocs in user-space headers
   - add proper documentation for the character device uAPI (both v1 and v2)
   - move the sysfs and gpio-mockup docs into the "obsolete" section
   - improve naming consistency for GPIO terms
   - clarify the line values description for sysfs
   - minor docs improvements
   - improve the driver API contract for setting GPIO direction
   - mark unsafe APIs as deprecated in kerneldocs and suggest
     replacements

  Other:
   - remove an obsolete test from selftests"

* tag 'gpio-updates-for-v6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux: (79 commits)
  gpio: sysfs: repair export returning -EPERM on 1st attempt
  selftest: gpio: remove obsolete gpio-mockup test
  gpiolib: Deduplicate cleanup for-loop in gpiochip_add_data_with_key()
  dt-bindings: gpio: aspeed,ast2400-gpio: Convert to DT schema
  gpio: acpi: Make acpi_gpio_count() take firmware node as a parameter
  gpio: of: Make of_gpio_get_count() take firmware node as a parameter
  gpiolib: Pass consumer device through to core in devm_fwnode_gpiod_get_index()
  gpio: sim: use for_each_hwgpio()
  gpio: provide for_each_hwgpio()
  gpio: don't warn about removing GPIO chips with active users anymore
  gpio: sim: delimit the fwnode name with a ":" when generating labels
  gpio: sim: add lockdep asserts
  gpio: Add ChromeOS EC GPIO driver
  gpio: constify of_phandle_args in of_find_gpio_device_by_xlate()
  gpio: fix memory leak in gpiod_request_commit()
  gpio: constify opaque pointer "data" in gpio_device_find()
  gpio: cdev: fix a NULL-pointer dereference with DEBUG enabled
  gpio: uapi: clarify default_values being logical
  gpio: sysfs: fix inverted pointer logic
  gpio: don't let lockdep complain about inherently dangerous RCU usage
  ...

Merge tag 'pwm/for-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux

2024-03-13T17:51:39+00:00

Pull pwm updates from Uwe Kleine-König:
 "This contains the usual amount of driver and device tree changes.
  Additionally there is a big rework of how pwm lowlevel drivers are
  registered to prepare adding character device support.

  Thanks to Dharma Balasubiramani, Dong Aisheng, Duje Mihanović, Jerome
  Brunet, Raag Jadav and Rafał Miłecki for their contributions. And
  sorry for those who still need some patience because I didn't manage
  to empty my review queue"

* tag 'pwm/for-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux: (185 commits)
  pwm: imx-tpm: fix probe crash due to access registers without clock
  pwm: meson: generalize 4 inputs clock on meson8 pwm type
  dt-bindings: pwm: amlogic: Add a new binding for meson8 pwm types
  dt-bindings: pwm: amlogic: fix s4 bindings
  pwm: dwc: simplify error handling
  pwm: dwc: Add 16 channel support for Intel Elkhart Lake
  pwm: dwc: drop redundant error check
  staging: greybus: pwm: Make use of devm_pwmchip_alloc() function
  staging: greybus: pwm: Rework how the number of PWM lines is determined
  staging: greybus: pwm: Drop unused gb_connection_set_data()
  staging: greybus: pwm: Rely on pwm framework to pass a valid hwpwm
  staging: greybus: pwm: Make use of pwmchip_parent() accessor
  staging: greybus: pwm: Change prototype of helpers to prepare further changes
  leds: qcom-lpg: Make use of devm_pwmchip_alloc() function
  drm/bridge: ti-sn65dsi86: Make use of devm_pwmchip_alloc() function
  drm/bridge: ti-sn65dsi86: Make use of pwmchip_parent() accessor
  gpio: mvebu: Make use of devm_pwmchip_alloc() function
  pwm: xilinx: Make use of devm_pwmchip_alloc() function
  pwm: xilinx: Prepare removing pwm_chip from driver data
  pwm: vt8500: Make use of devm_pwmchip_alloc() function
  ...

drivers/gpio/nomadik: move dummy nmk_gpio_dbg_show_one() to header

2024-03-12T11:53:35+00:00

When `CONFIG_DEBUG_FS` is disabled, nmk_gpio_dbg_show_one() is an
empty dummy function; this however triggers a `-Wmissing-prototypes`
warning and later a linker error because the function is also used by
drivers/pinctrl/nomadik/pinctrl-nomadik.c, therefore it needs to be
non-static.

To allow both sources to access this dummy function, this patch moves
it to the header, adding the `#ifdef CONFIG_DEBUG_FS` there as well.

Signed-off-by: Max Kellermann 
Link: https://lore.kernel.org/r/20240311133223.3429428-1-max.kellermann@ionos.com
Signed-off-by: Linus Walleij

gpio: nomadik: remove BUG_ON() in nmk_gpio_populate_chip()

2024-03-12T11:53:33+00:00

Using BUG_ON() is discouraged and also the check wasn't done early
enough to prevent an out of bounds access.  Check earlier and return
an error instead of calling BUG().

Signed-off-by: Dan Carpenter 
Link: https://lore.kernel.org/r/ae643df0-3a3e-4270-8dbf-be390ee4b478@moroto.mountain
Signed-off-by: Linus Walleij