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Author SHA1 Message Date
Bartosz Golaszewski
7fe595b3c3 gpio: don't dereference gdev->chip in gpiochip_setup_dev()
We don't need to dereference gdev->chip in gpiochip_setup_dev() as at
the time it's called, the label in the associated struct gpio_device is
already set.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 10:51:17 +01:00
Bartosz Golaszewski
5694f274a0 gpio: sysfs: don't access gdev->chip if it's not needed
Don't dereference gdev->chip if the same information can be obtained
from struct gpio_device.

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 10:51:13 +01:00
Bartosz Golaszewski
3c7a47f6c5 gpio: cdev: don't access gdev->chip if it's not needed
The variable holding the number of GPIO lines is duplicated in GPIO
device so read it instead of unnecessarily dereferencing the chip
pointer.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 10:51:10 +01:00
Bartosz Golaszewski
f4e14d45d7 gpio: cdev: replace gpiochip_get_desc() with gpio_device_get_desc()
gpio_device_get_desc() is the safer alternative to gpiochip_get_desc().
As we don't really need to dereference the chip pointer to retrieve the
descriptors in character device code, let's use it.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 10:51:03 +01:00
Bartosz Golaszewski
b93bca4bd6 gpio: sysfs: pass the GPIO device - not chip - to sysfs callbacks
We're working towards protecting the chip pointer in struct gpio_device
with SRCU. In order to use it in sysfs callbacks we must pass the pointer
to the GPIO device that wraps the chip instead of the address of the
chip itself as the user data.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 10:50:58 +01:00
Bartosz Golaszewski
59cba4a0e6 gpio: sysfs: extend the critical section for unregistering sysfs devices
Checking the gdev->mockdev pointer for NULL must be part of the critical
section.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 10:50:55 +01:00
Bartosz Golaszewski
b6f87adbac gpio: remove unneeded code from gpio_device_get_desc()
The GPIO chip pointer is unused. Let's remove it.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 10:50:52 +01:00
Bartosz Golaszewski
2559f2e092 gpio: reinforce desc->flags handling
We now removed the gpio_lock spinlock and modified the places
previously protected by it to handle desc->flags access in a consistent
way. Let's improve other places that were previously unprotected by
reading the flags field of gpio_desc once and using the stored value for
logic consistency. If we need to modify the field, let's also write it
back once with a consistent value resulting from the function's logic.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 10:50:49 +01:00
Bartosz Golaszewski
35b545332b gpio: remove gpio_lock
The "multi-function" gpio_lock is pretty much useless with how it's used
in GPIOLIB currently. Because many GPIO API calls can be called from all
contexts but may also call into sleeping driver callbacks, there are
many places with utterly broken workarounds like yielding the lock to
call a possibly sleeping function and then re-acquiring it again without
taking into account that the protected state may have changed.

It was also used to protect several unrelated things: like individual
descriptors AND the GPIO device list. We now serialize access to these
two with SRCU and so can finally remove the spinlock.

There is of course the question of consistency of lockless access to
GPIO descriptors. Because we only support exclusive access to GPIOs
(officially anyway, I'm looking at you broken
GPIOD_FLAGS_BIT_NONEXCLUSIVE bit...) and the API contract with providers
does not guarantee serialization, it's enough to ensure we cannot
accidentally dereference an invalid pointer and that the state we present
to both users and providers remains consistent. To achieve that: read the
flags field atomically except for a few special cases. Read their current
value before executing callback code and use this value for any subsequent
logic. Modifying the flags depends on the particular use-case and can
differ. For instance: when requesting a GPIO, we need to set the
REQUESTED bit immediately so that the next user trying to request the
same line sees -EBUSY.

While at it: the allocations that used GFP_ATOMIC until this point can
now switch to GFP_KERNEL.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 10:50:45 +01:00
Bartosz Golaszewski
2a9101e875 gpio: sysfs: use gpio_device_find() to iterate over existing devices
With the list of GPIO devices now protected with SRCU we can use
gpio_device_find() to traverse it from sysfs.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 10:50:42 +01:00
Bartosz Golaszewski
1f2bcb8c8c gpio: protect the descriptor label with SRCU
In order to ensure that the label is not freed while it's being
accessed, let's protect it with SRCU and synchronize it everytime it's
changed.

Let's modify desc_set_label() to manage the memory used for the label as
it can only be freed once synchronize_srcu() returns.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 10:50:40 +01:00
Bartosz Golaszewski
be711caa87 gpio: add SRCU infrastructure to struct gpio_desc
Extend the GPIO descriptor with an SRCU structure in order to serialize
the access to the label. Initialize and clean it up where applicable.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 10:50:37 +01:00
Bartosz Golaszewski
ccfb6ff4f6 gpio: don't set label from irq helpers
We will soon serialize access to the descriptor label using SRCU. The
write-side of the protection will require calling synchronize_srcu()
which must not be called from atomic context. We have two irq helpers:
gpiochip_lock_as_irq() and gpiochip_unlock_as_irq() that set the label
if the GPIO is not requested but is being used as interrupt. They are
called with a spinlock held from the interrupt subsystem.

They must not do it if we are to use SRCU so instead let's move the
special corner case to a dedicated getter.

Don't actually set the label to "interrupt" in the above case but rather
use the newly added gpiod_get_label() helper to hide the logic that
atomically checks the descriptor flags and returns the address of a
static "interrupt" string.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 10:50:34 +01:00
Bartosz Golaszewski
d23dc4a9a8 gpio: provide and use gpiod_get_label()
We will soon serialize access to the descriptor label using SRCU. The
write-side of the protection will require calling synchronize_srcu()
which must not be called from atomic context. We have two irq helpers:
gpiochip_lock_as_irq() and gpiochip_unlock_as_irq() that set the label
if the GPIO is not requested but is being used as interrupt. They are
called with a spinlock held from the interrupt subsystem.

They must not do it if we are to use SRCU so instead let's move the
special corner case to a dedicated getter.

First: let's implement and use the getter where it's applicable.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 10:50:30 +01:00
Bartosz Golaszewski
0857c39bfd gpio: remove unused logging helpers
The general rule of the kernel is to not provide symbols that have no
users upstream. Let's remove logging helpers that are not used anywhere.

This will save us work later when we'll be modifying them to use the
upcoming SRCU infrastructure.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 10:50:27 +01:00
Bartosz Golaszewski
8ce6fd81a4 gpio: of: assign and read the hog pointer atomically
The device nodes representing GPIO hogs cannot be deleted without
unregistering the GPIO chip so there's no need to serialize their access.
However we must ensure that users can get the right address so write and
read it atomically.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 10:50:24 +01:00
Bartosz Golaszewski
e348544f79 gpio: protect the list of GPIO devices with SRCU
We're working towards removing the "multi-function" GPIO spinlock that's
implemented terribly wrong. We tried using an RW-semaphore to protect
the list of GPIO devices but it turned out that we still have old code
using legacy GPIO calls that need to translate the global GPIO number to
the address of the associated descriptor and - to that end - traverse
the list while holding the lock. If we change the spinlock to a sleeping
lock then we'll end up with "scheduling while atomic" bugs.

Let's allow lockless traversal of the list using SRCU and only use the
mutex when modyfing the list.

While at it: let's protect the period between when we start the lookup
and when we finally request the descriptor (increasing the reference
count of the GPIO device) with the SRCU read lock.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-12 10:50:20 +01:00
Krzysztof Kozlowski
faf6efd2e5 gpio: constify opaque pointer in gpio_device_find() match function
The match function used in gpio_device_find() should not modify the
contents of passed opaque pointer, because such modification would not
be necessary for actual matching and it could lead to quite unreadable,
spaghetti code.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[Bartosz: fix coding style in header]
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-02-12 10:18:31 +01:00
Bartosz Golaszewski
104e00bbc7 Linux 6.8-rc4
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Merge tag 'v6.8-rc4' into gpio/for-next

Linux 6.8-rc4

Pulling this for a bugfix upstream with which the gpio/for-next branch
conflicts.
2024-02-12 10:12:41 +01:00
Bartosz Golaszewski
aab5c6f200 gpio: set device type for GPIO chips
It's useful to have the device type information for those sub-devices
that are actually GPIO chips registered with GPIOLIB. While at it: use
the device type struct to setup the release callback which is the
preferred way to use the device API.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-08 10:35:59 +01:00
Bartosz Golaszewski
2526dffc6d gpio: remove GPIO device from the list unconditionally in error path
Since commit 48e1b4d369 ("gpiolib: remove the GPIO device from the list
when it's unregistered") we remove the GPIO device entry from the global
list (used to order devices by their GPIO ranges) when unregistering the
chip, not when releasing the device. It will not happen when the last
reference is put anymore. This means, we need to remove it in error path
in gpiochip_add_data_with_key() unconditionally, without checking if the
device's .release() callback is set.

Fixes: 48e1b4d369 ("gpiolib: remove the GPIO device from the list when it's unregistered")
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-02-08 10:33:03 +01:00
Ricardo B. Marliere
a875746f60 gpio: gpiolib: make gpio_bus_type const
Now that the driver core can properly handle constant struct bus_type,
move the gpio_bus_type variable to be a constant structure as well,
placing it into read-only memory which can not be modified at runtime.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-02-05 09:42:21 +01:00
Martin Kaiser
3eac8bbed2 gpio: vf610: enable COMPILE_TEST
Enable COMPILE_TEST for the vf610 gpio driver to support test builds on
systems without this hardware.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-02-02 14:32:12 +01:00
Martin Kaiser
f575957882 gpio: vf610: allow disabling the vf610 driver
The vf610 gpio driver is enabled by default for all i.MX machines,
without any option to disable it in a board-specific config file.

Most i.MX chipsets have no hardware for this driver. Change the default
to enable GPIO_VF610 for SOC_VF610 and disable it otherwise.

Add a text description after the bool type, this makes the driver
selectable by make config etc.

Fixes: 30a35c07d9 ("gpio: vf610: drop the SOC_VF610 dependency for GPIO_VF610")
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-02-02 14:32:03 +01:00
Bartosz Golaszewski
88b7049635 gpio: unexport GPIO irq domain functions only used internally
There are no external users for the irq domain helpers so unexport them
and remove the prototypes from the driver header.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-29 11:45:49 +01:00
Bartosz Golaszewski
83a517c777 gpio: cdev: remove leftover function pointer typedefs
The locking wrappers were replaces with lock guards. These typedefs are
no longer needed.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Kent Gibson <warthog618@gmail.com>
2024-01-29 11:45:49 +01:00
Wenhua Lin
84aef4ed59 gpio: eic-sprd: Clear interrupt after set the interrupt type
The raw interrupt status of eic maybe set before the interrupt is enabled,
since the eic interrupt has a latch function, which would trigger the
interrupt event once enabled it from user side. To solve this problem,
interrupts generated before setting the interrupt trigger type are ignored.

Fixes: 25518e024e ("gpio: Add Spreadtrum EIC driver support")
Acked-by: Chunyan Zhang <zhang.lyra@gmail.com>
Signed-off-by: Wenhua Lin <Wenhua.Lin@unisoc.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-22 11:38:08 +01:00
Wenhua Lin
44a0d880b9 gpio: eic-sprd: Optimize the calculation method of eic number
The num_eics is a default value, but some SoCs support more than 8.
In order to adapt to all projects, the total number of eics is
automatically calculated through dts.

Signed-off-by: Wenhua Lin <Wenhua.Lin@unisoc.com>
Acked-by: Chunyan Zhang <zhang.lyra@gmail.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-22 11:37:59 +01:00
Mario Limonciello
805c74eac8 gpiolib: acpi: Ignore touchpad wakeup on GPD G1619-04
Spurious wakeups are reported on the GPD G1619-04 which
can be absolved by programming the GPIO to ignore wakeups.

Cc: stable@vger.kernel.org
Reported-and-tested-by: George Melikov <mail@gmelikov.ru>
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3073
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-22 10:05:44 +01:00
Bartosz Golaszewski
f4028860a9 gpio: legacy: mark old interfaces as deprecated in kernel docs
We've recently had someone try to use of_get_named_gpio() in new code.
Mark legacy interfaces as deprecated in kernel docs to avoid any
confusion.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-22 09:43:33 +01:00
Linus Torvalds
3455135839 gpio fixes for v6.8-rc1
- revert the changes aiming to use a read-write semaphore to protect the
   list of GPIO devices due to calls to legacy API taking that lock from
   atomic context in old code
 - fix inverted logic in DEFINE_FREE() for GPIO device references
 - check the return value of bgpio_init() in gpio-mlxbf3
 - fix node address in the DT bindings example for gpio-xilinx
 - fix signedness bug in gpio-rtd
 - fix kernel-doc warnings in gpio-en7523
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Merge tag 'gpio-fixes-for-v6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux

Pull gpio fixes from Bartosz Golaszewski:
 "Apart from some regular driver fixes there's a relatively big revert
  of the locking changes that were introduced to GPIOLIB in this merge
  window.

  This is because it turned out that some legacy GPIO interfaces - that
  need to translate a number from the global GPIO numberspace to the
  address of the relevant descriptor, thus running a GPIO device lookup
  and taking the GPIO device list lock - are still used in old code from
  atomic context resulting in "scheduling while atomic" errors.

  I'll try to make the read-only part of the list access entirely
  lockless using SRCU but this will take some time so let's go back to
  the old global spinlock for now.

  Summary:

   - revert the changes aiming to use a read-write semaphore to protect
     the list of GPIO devices due to calls to legacy API taking that
     lock from atomic context in old code

   - fix inverted logic in DEFINE_FREE() for GPIO device references

   - check the return value of bgpio_init() in gpio-mlxbf3

   - fix node address in the DT bindings example for gpio-xilinx

   - fix signedness bug in gpio-rtd

   - fix kernel-doc warnings in gpio-en7523"

* tag 'gpio-fixes-for-v6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
  gpiolib: revert the attempt to protect the GPIO device list with an rwsem
  gpio: EN7523: fix kernel-doc warnings
  gpiolib: Fix scope-based gpio_device refcounting
  gpio: mlxbf3: add an error code check in mlxbf3_gpio_probe
  dt-bindings: gpio: xilinx: Fix node address in gpio
  gpio: rtd: Fix signedness bug in probe
2024-01-18 17:03:51 -08:00
Linus Torvalds
21c91bb936 - New Drivers
- Add support for Monolithic Power Systems MP3309C WLED Step-up Converter
 
  - Fix-ups
    - Use/convert to new/better APIs/helpers/MACROs instead of hand-rolling implementations
    - Device Tree Binding updates
    - Demote non-kerneldoc header comments
    - Improve error handling; return proper error values, simplify, avoid duplicates, etc
    - Convert over to the new (kinda) GPIOD API
 
  - Bug Fixes
    - Fix uninitialised local variable
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Merge tag 'backlight-next-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight

Pull backlight updates from Lee Jones:
 "New Drivers:
   - Add support for Monolithic Power Systems MP3309C WLED Step-up Converter

  Fix-ups:
   - Use/convert to new/better APIs/helpers/MACROs instead of
     hand-rolling implementations
   - Device Tree Binding updates
   - Demote non-kerneldoc header comments
   - Improve error handling; return proper error values, simplify, avoid
     duplicates, etc
   - Convert over to the new (kinda) GPIOD API

  Bug Fixes:
   - Fix uninitialised local variable"

* tag 'backlight-next-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
  backlight: hx8357: Convert to agnostic GPIO API
  backlight: ili922x: Add an error code check in ili922x_write()
  backlight: ili922x: Drop kernel-doc for local macros
  backlight: mp3309c: Fix uninitialized local variable
  backlight: pwm_bl: Use dev_err_probe
  backlight: mp3309c: Add support for MPS MP3309C
  dt-bindings: backlight: mp3309c: Remove two required properties
2024-01-18 16:53:35 -08:00
Bartosz Golaszewski
efb8235bfd gpiolib: revert the attempt to protect the GPIO device list with an rwsem
This reverts commits 1979a28075 ("gpiolib: replace the GPIO device
mutex with a read-write semaphore") and 65a828bab1 ("gpiolib: use
a mutex to protect the list of GPIO devices").

Unfortunately the legacy GPIO API that's still used in older code has to
translate numbers from the global GPIO numberspace to descriptors. This
results in a GPIO device lookup in every call to legacy functions. Some
of those functions - like gpio_set/get_value() - can be called from
atomic context so taking a sleeping lock that is an RW semaphore results
in an error.

We'll probably have to protect this list with SRCU.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/linux-wireless/f7b5ff1e-8f34-4d98-a7be-b826cb897dc8@moroto.mountain/
Fixes: 1979a28075 ("gpiolib: replace the GPIO device mutex with a read-write semaphore")
Fixes: 65a828bab1 ("gpiolib: use a mutex to protect the list of GPIO devices")
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-17 09:52:37 +01:00
Randy Dunlap
62b38f30a0 gpio: EN7523: fix kernel-doc warnings
Add "struct" keyword and explain the @dir array differently to
prevent kernel-doc warnings:

gpio-en7523.c:22: warning: cannot understand function prototype: 'struct airoha_gpio_ctrl '
gpio-en7523.c:27: warning: Function parameter or struct member 'dir' not described in 'airoha_gpio_ctrl'
gpio-en7523.c:27: warning: Excess struct member 'dir0' description in 'airoha_gpio_ctrl'
gpio-en7523.c:27: warning: Excess struct member 'dir1' description in 'airoha_gpio_ctrl'

Fixes: 0868ad385a ("gpio: Add support for Airoha EN7523 GPIO controller")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-15 23:15:35 +01:00
Su Hui
d460e9c207 gpio: mlxbf3: add an error code check in mlxbf3_gpio_probe
Clang static checker warning: Value stored to 'ret' is never read.
bgpio_init() returns error code if failed, it's better to add this
check.

Fixes: cd33f216d2 ("gpio: mlxbf3: Add gpio driver support")
Signed-off-by: Su Hui <suhui@nfschina.com>
[Bartosz: add the Fixes: tag]
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-15 11:11:29 +01:00
Dan Carpenter
c8fb5a52b9 gpio: rtd: Fix signedness bug in probe
The "data->irqs[]" array holds unsigned int so this error handling will
not work correctly.

Fixes: eee636bff0 ("gpio: rtd: Add support for Realtek DHC(Digital Home Center) RTD SoCs")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-15 11:07:46 +01:00
Bartosz Golaszewski
1979a28075 gpiolib: replace the GPIO device mutex with a read-write semaphore
There are only two spots where we modify (add to or remove objects from)
the GPIO device list. Readers should be able to access it concurrently.
Replace the mutex with a read-write semaphore and adjust the locking
operations accordingly.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2024-01-04 10:29:16 +01:00
Bartosz Golaszewski
48e1b4d369 gpiolib: remove the GPIO device from the list when it's unregistered
If we wait until the GPIO device's .release() callback gets invoked
before we remove it from the global device list, then we risk that
someone will look it up using gpio_device_find() between where we
dropped the last reference and before .release() is done taking a
reference again to an object that's being released.

The device must be removed when it's being unregistered - just like how
we remove it from the GPIO bus.

Fixes: ff2b135922 ("gpio: make the gpiochip a real device")
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2024-01-04 10:29:16 +01:00
Jim Liu
c4f8457d17 gpio: nuvoton: Add Nuvoton NPCM sgpio driver
Add Nuvoton BMC NPCM7xx/NPCM8xx sgpio driver support.
Nuvoton NPCM SGPIO module is combine serial to parallel IC (HC595)
and parallel to serial IC (HC165), and use APB3 clock to control it.
This interface has 4 pins  (D_out , D_in, S_CLK, LDSH).
BMC can use this driver to increase 64 GPI pins and 64 GPO pins to use.

Signed-off-by: Jim Liu <JJLIU0@nuvoton.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-03 11:25:41 +01:00
Tzuyi Chang
eee636bff0 gpio: rtd: Add support for Realtek DHC(Digital Home Center) RTD SoCs
This driver enables configuration of GPIO direction, GPIO values, GPIO
debounce settings and handles GPIO interrupts.

Signed-off-by: Tzuyi Chang <tychang@realtek.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-03 10:46:21 +01:00
Wenhua Lin
0f57b21300 gpio: pmic-eic-sprd: Configure the bit corresponding to the EIC through offset
A bank PMIC EIC contains 16 EICs, and the operating registers
are BIT0-BIT15, such as BIT0 of the register operated by EIC0.
Using the one-dimensional array reg[CACHE_NR_REGS] for maintenance
will cause the configuration of other EICs to be affected when
operating a certain EIC. In order to solve this problem, configure
the bit corresponding to the EIC through offset.

Signed-off-by: Wenhua Lin <Wenhua.Lin@unisoc.com>
Reviewed-by: Chunyan Zhang <zhang.lyra@gmail.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-03 09:50:47 +01:00
Emil Renner Berthing
f34fd6ee1b gpio: dwapb: Use generic request, free and set_config
This way GPIO will be denied on pins already claimed by other devices
and basic pin configuration (pull-up, pull-down etc.) can be done
through the userspace GPIO API.

Signed-off-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-02 14:16:17 +01:00
Bartosz Golaszewski
513246a34b gpio: sysfs: drop tabs from local variable declarations
Older code has an annoying habit of putting tabs between the type and the
name of the variable. This doesn't really add to readability and newer
code doesn't do it so make the entire file consistent.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2023-12-27 16:01:37 +01:00
Bartosz Golaszewski
0338f6a6fb gpiolib: drop tabs from local variable declarations
Older code has an annoying habit of putting tabs between the type and the
name of the variable. This doesn't really add to readability and newer
code doesn't do it so make the entire file consistent.

While at it: convert 'unsigned' to 'unsigned int'.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2023-12-27 16:00:17 +01:00
Bartosz Golaszewski
5d5dfc50e5 gpiolib: remove extra_checks
extra_checks is only used in a few places. It also depends on
a non-standard DEBUG define one needs to add to the source file. The
overhead of removing it should be minimal (we already use pure
might_sleep() in the code anyway) so drop it.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2023-12-27 15:58:39 +01:00
Bartosz Golaszewski
7dd1871e50 gpio: tps65219: don't use CONFIG_DEBUG_GPIO
CONFIG_DEBUG_GPIO should only be used to enable debug log messages and
for core GPIOLIB debugging. Don't use it to control the execution of
potentially buggy code. Just put it under an always-false #if.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
2023-12-27 15:56:48 +01:00
Kent Gibson
20bddcb40b gpiolib: cdev: replace locking wrappers for gpio_device with guards
Replace the wrapping functions that inhibit removal of the gpio chip
with equivalent guards.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2023-12-27 15:45:45 +01:00
Kent Gibson
32d8e3b645 gpiolib: cdev: replace locking wrappers for config_mutex with guards
After the adoption of guard(), the locking wrappers that hold the
config_mutex for linereq_set_values() and linereq_set_config() no
longer add value, so combine them into the functions they wrap.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2023-12-27 15:45:30 +01:00
Kent Gibson
b718fbfea9 gpiolib: cdev: allocate linereq using kvzalloc()
The size of struct linereq may exceed a page, so allocate space for
it using kvzalloc() instead of kzalloc() to handle the case where
memory is heavily fragmented and kzalloc() cannot find a sufficient
contiguous region.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2023-12-27 15:43:56 +01:00
Kent Gibson
ede7511e7c gpiolib: cdev: include overflow.h
struct_size() is used to calculate struct linereq size, so explicitly
include overflow.h.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2023-12-27 15:43:40 +01:00