Commit Graph

810 Commits

Author SHA1 Message Date
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
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
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
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
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
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
Kent Gibson
d8543cbaf9 gpiolib: remove debounce_period_us from struct gpio_desc
cdev is the only user of the debounce_period_us field in
struct gpio_desc, and it no longer uses it, so remove it.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2023-12-19 09:45:45 +01:00
Bartosz Golaszewski
65a828bab1 gpiolib: use a mutex to protect the list of GPIO devices
The global list of GPIO devices is never modified or accessed from
atomic context so it's fine to protect it using a mutex. Add a new
global lock dedicated to the gpio_devices list and use it whenever
accessing or modifying it.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2023-12-18 10:00:43 +01:00
Bartosz Golaszewski
f95fd4ac15 gpiolib: rename static functions that are called with the lock taken
Rename two functions that read or modify the global GPIO device list but
don't take the lock themselves (and need to be called with it already
acquired). Use the _unlocked() suffix which seems to be used quite
consistently across the kernel despite there also existing the _locked()
suffix for the same purpose.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2023-12-18 09:59:20 +01:00
Bartosz Golaszewski
0a10d10781 gpiolib: allocate memory atomically with a spinlock held
We will eventually switch to protecting the GPIO descriptors with a mutex
but until then, we need to allocate memory for the label copy atomically
while we're holding the global spinlock.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/linux-gpio/62588146-eed6-42f7-ba26-160226b109fe@moroto.mountain/T/#u
Fixes: f8d05e276b ("gpiolib: remove gpiochip_is_requested()")
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2023-12-15 16:43:24 +01:00
Bartosz Golaszewski
11a94a335a gpio: remove gpiochip_is_requested()
- provide a safer alternative to gpiochip_is_requested()
 - convert all existing users
 - remove gpiochip_is_requested()
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Merge tag 'gpio-remove-gpiochip_is_requested-for-v6.8-rc1' into gpio/for-next

gpio: remove gpiochip_is_requested()

- provide a safer alternative to gpiochip_is_requested()
- convert all existing users
- remove gpiochip_is_requested()
2023-12-08 09:37:12 +01:00
Bartosz Golaszewski
f8d05e276b gpiolib: remove gpiochip_is_requested()
We have no external users of gpiochip_is_requested(). Let's remove it
and replace its internal calls with direct testing of the REQUESTED flag.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
2023-12-08 09:26:43 +01:00
Bartosz Golaszewski
ee25fba76a gpiolib: provide gpiochip_dup_line_label()
gpiochip_is_requested() not only has a misleading name but it returns
a pointer to a string that is freed when the descriptor is released.

Provide a new helper meant to replace it, which returns a copy of the
label string instead.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
2023-12-08 09:25:53 +01:00
Bartosz Golaszewski
d1f7728259 gpiolib: provide gpio_device_get_label()
Provide a getter for the GPIO device label string so that users don't
have to dereference struct gpio_chip directly.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2023-11-24 20:27:37 +01:00
Bartosz Golaszewski
acf2981b84 treewide: rename pinctrl_gpio_set_config_new()
Now that pinctrl_gpio_set_config() is no longer used, let's drop the
'_new' suffix from its improved variant.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
2023-11-04 10:23:22 +01:00
Bartosz Golaszewski
4fccb263f3 treewide: rename pinctrl_gpio_free_new()
Now that pinctrl_gpio_free()() is no longer used, let's drop the '_new'
suffix from its improved variant.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
2023-11-04 10:23:21 +01:00
Bartosz Golaszewski
acb38be654 treewide: rename pinctrl_gpio_request_new()
Now that pinctrl_gpio_request() is no longer used, let's drop the '_new'
suffix from its improved variant.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
2023-11-04 10:23:21 +01:00
Bartosz Golaszewski
e3d3ab299b gpiolib: generic: use new pinctrl GPIO helpers
Replace the pinctrl helpers taking the global GPIO number as argument
with the improved variants that instead take a pointer to the GPIO chip
and the controller-relative offset.

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>
2023-11-04 10:23:18 +01:00
Bartosz Golaszewski
2654521d77 gpiolib: remove gpiochip_find()
With all users of gpiochip_find() converted to using gpio_device_find(),
we can now remove this function from the kernel.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2023-11-04 10:22:52 +01:00
Bartosz Golaszewski
8c85a102fc gpiolib: provide gpio_device_get_base()
Let's start adding getters for the opaque struct gpio_device. Start with
a function allowing to retrieve the base GPIO number.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
2023-10-13 09:05:57 +02:00
Bartosz Golaszewski
370232d096 gpiolib: provide gpiod_to_gpio_device()
Accessing struct gpio_chip backing a GPIO device is only allowed for the
actual providers of that chip.

Similarly to how we introduced gpio_device_find() in order to replace
the abused gpiochip_find(), let's introduce a counterpart to
gpiod_to_chip() that returns a reference to the GPIO device owning the
descriptor. This is done in order to later remove gpiod_to_chip()
entirely.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Peter Rosin <peda@axentia.se>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
2023-10-13 08:50:04 +02:00
Bartosz Golaszewski
1559d14977 gpiolib: provide gpio_device_to_device()
There are users in the kernel who need to retrieve the address of the
struct device backing the GPIO device. Currently they needlessly poke in
the internals of GPIOLIB. Add a dedicated getter function.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Peter Rosin <peda@axentia.se>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
2023-10-13 08:50:01 +02:00
Andy Shevchenko
668706b10c gpiolib: provide gpio_device_find_by_fwnode()
One of the ways of looking up GPIO devices is using their fwnode.
Provide a helper for that to avoid every user implementing their
own matching function.

Reviewed-by: Dipen Patel <dipenp@nvidia.com>
Tested-by: Dipen Patel <dipenp@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20231010151709.4104747-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2023-10-12 10:36:39 +02:00
Bartosz Golaszewski
db54696044 gpiolib: replace find_chip_by_name() with gpio_device_find_by_label()
Remove all remaining uses of find_chip_by_name() (and subsequently:
gpiochip_find()) from gpiolib.c and use the new
gpio_device_find_by_label() instead.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2023-10-04 13:35:49 +02:00
Bartosz Golaszewski
9b41878084 gpiolib: reluctantly provide gpio_device_get_chip()
The process of converting all unauthorized users of struct gpio_chip to
using dedicated struct gpio_device function will be long so in the
meantime we must provide a way of retrieving the pointer to struct
gpio_chip from a GPIO device.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2023-10-04 13:30:15 +02:00
Bartosz Golaszewski
93548f8bbb gpiolib: provide gpio_device_get_desc()
Getting the GPIO descriptor directly from the gpio_chip struct is
dangerous as we don't take the reference to the underlying GPIO device.
In order to start working towards removing gpiochip_get_desc(), let's
provide a safer variant that works with an existing reference to struct
gpio_device.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2023-10-04 13:29:56 +02:00
Bartosz Golaszewski
d62fcd9f18 gpiolib: provide gpio_device_find_by_label()
By far the most common way of looking up GPIO devices is using their
label. Provide a helpers for that to avoid every user implementing their
own matching function.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2023-10-04 13:29:45 +02:00
Bartosz Golaszewski
cfe102f633 gpiolib: provide gpio_device_find()
gpiochip_find() is wrong and its kernel doc is misleading as the
function doesn't return a reference to the gpio_chip but just a raw
pointer. The chip itself is not guaranteed to stay alive, in fact it can
be deleted at any point. Also: other than GPIO drivers themselves,
nobody else has any business accessing gpio_chip structs.

Provide a new gpio_device_find() function that returns a real reference
to the opaque gpio_device structure that is guaranteed to stay alive for
as long as there are active users of it.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2023-10-04 13:29:31 +02:00
Bartosz Golaszewski
36aa129f22 gpiolib: make gpio_device_get() and gpio_device_put() public
In order to start migrating away from accessing struct gpio_chip by
users other than their owners, let's first make the reference management
functions for the opaque struct gpio_device public in the driver.h
header.

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>
2023-10-04 13:28:58 +02:00
Bartosz Golaszewski
c31071eabb gpiolib: extend the critical sections of lookup tables
There are two places in the code where we retrieve a lookup table using
gpiod_find_lookup_table() (which protects the table list with the lookup
table lock) and then use it after the lock is released.

We need to keep the lookup table mutex locked the entire time we're using
the tables. Remove the locking from gpiod_find_lookup_table() and use
guards to protect the code actually using the table objects.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2023-10-02 15:34:32 +02:00
Bartosz Golaszewski
f42dafe3da gpiolib: unexport gpiod_set_transitory()
There are no and never have been any users of gpiod_set_transitory()
outside the core GPIOLIB code. Make it private.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2023-09-11 11:17:05 +02:00
Linus Torvalds
f97e18a3f2 gpio updates for v6.6
Core GPIOLIB updates:
 - wake-up poll() in user-space on device unbind
 - improve fwnode usage
 - interrupt domain handling improvements
 - correctly handle the ngpios property in gpio-mmio
 
 Driver cleanups:
 - remove unneeded calls to platform_set_drvdata() all around the place
 - remove unneeded of_match_ptr() expansions whenever a driver depends on
   CONFIG_OF
 - remove redundant calls to dev_err_probe() from gpio-omap and gpio-davinci
 
 Driver improvements:
 - use autopointers and guards from cleanup.h in gpio-sim
 - shrink code in gpio-sim using some common helpers
 - convert the idio family of drivers to using gpio-regmap
 - convert gpio-ws16c48 to using gpio-regmap
 - use devres to simplify code in gpio-pisosr and gpio-mxc
 - update gpio-sifive: support IRQ wake, improve interrupt handling, allow
   building as module
 - make gpio-ge and gpio-bcm-kona OF-independent (plus some minor tweaks)
 - add support for new models in gpio-pca953x and gpio-ds4520
 - add runtime PM support to gpio-mxc
 - fix a build warning in gpio-mxs
 - add support for adding pin ranges to gpio-mlxbf3
 - add counter/timer support to gpio-104-dio-48e
 - switch to dynamic GPIO base allocation in gpio-vf610
 - minor oneliners here and there
 
 Device-tree bindings updates:
 - enable the gpio-line-names property in snps,dw-apb and STMPE GPIO
 - document new models in fsl-imx-gpio, ds4520 and pca95xx
 - convert the bindings for brcm,kona-gpio to YAML
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Merge tag 'gpio-updates-for-v6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux

Pull gpio updates from Bartosz Golaszewski:
 "We have a lot of code refactoring using common helpers and ended up
  removing more lines then we're adding this release cycle.

  Nothing really stands out, just small updates all over the place.

  Core GPIOLIB updates:
   - wake-up poll() in user-space on device unbind
   - improve fwnode usage
   - interrupt domain handling improvements
   - correctly handle the ngpios property in gpio-mmio

  Driver cleanups:
   - remove unneeded calls to platform_set_drvdata() all around the
     place
   - remove unneeded of_match_ptr() expansions whenever a driver depends
     on CONFIG_OF
   - remove redundant calls to dev_err_probe() from gpio-omap and
     gpio-davinci

  Driver improvements:
   - use autopointers and guards from cleanup.h in gpio-sim
   - shrink code in gpio-sim using some common helpers
   - convert the idio family of drivers to using gpio-regmap
   - convert gpio-ws16c48 to using gpio-regmap
   - use devres to simplify code in gpio-pisosr and gpio-mxc
   - update gpio-sifive: support IRQ wake, improve interrupt handling,
     allow building as module
   - make gpio-ge and gpio-bcm-kona OF-independent (plus some minor
     tweaks)
   - add support for new models in gpio-pca953x and gpio-ds4520
   - add runtime PM support to gpio-mxc
   - fix a build warning in gpio-mxs
   - add support for adding pin ranges to gpio-mlxbf3
   - add counter/timer support to gpio-104-dio-48e
   - switch to dynamic GPIO base allocation in gpio-vf610
   - minor oneliners here and there

  Device-tree bindings updates:
   - enable the gpio-line-names property in snps,dw-apb and STMPE GPIO
   - document new models in fsl-imx-gpio, ds4520 and pca95xx
   - convert the bindings for brcm,kona-gpio to YAML"

* tag 'gpio-updates-for-v6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux: (94 commits)
  gpio: pca953x: add support for TCA9538
  dt-bindings: gpio: pca95xx: document new tca9538 chip
  gpio: pca953x: Use i2c_get_match_data()
  gpio: mlxbf3: use capital "OR" for multiple licenses in SPDX
  gpio: pcf857x: Extend match data support for OF tables
  gpio: vf610: switch to dynamic allocat GPIO base
  gpiolib: provide and use gpiod_line_state_notify()
  gpio: cdev: wake up lineevent poll() on device unbind
  gpio: cdev: wake up linereq poll() on device unbind
  gpio: cdev: wake up chardev poll() on device unbind
  gpiolib: add a second blocking notifier to struct gpio_device
  gpio: cdev: open-code to_gpio_chardev_data()
  gpiolib: rename the gpio_device notifier
  gpio: mlxbf3: Support add_pin_ranges()
  gpio: mxc: Use helper function devm_clk_get_optional_enabled()
  gpio: pca9570: fix kerneldoc
  gpio: sim: simplify code with cleanup helpers
  gpio: sim: replace memmove() + strstrip() with skip_spaces() + strim()
  gpio: sim: simplify gpio_sim_device_config_live_store()
  gpio: mxc: release the parent IRQ in runtime suspend
  ...
2023-08-29 10:21:56 -07:00
Bartosz Golaszewski
9ce4ed5b4d gpiolib: provide and use gpiod_line_state_notify()
Wrap the calls to blocking_notifier_call_chain() for the line state
notifier with a helper that allows us to use fewer lines of code and
simpler syntax.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2023-08-22 09:37:46 +02:00
Bartosz Golaszewski
a067419ba7 gpiolib: add a second blocking notifier to struct gpio_device
Add a new blocking notifier to struct gpio_device and use it to notify
subscribers about the GPIO device being unregistered from the device
model.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Kent Gibson <warthog618@gmail.com>
2023-08-21 15:57:05 +02:00
Bartosz Golaszewski
17a7ca3589 gpiolib: rename the gpio_device notifier
Change the generic "notifier" name to "line_state_notifier" in order to
reflect its purpose in preparation for adding a second notifier which
will be used to notify wait queues about device unregistering.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Kent Gibson <warthog618@gmail.com>
2023-08-21 15:57:05 +02:00
Bartosz Golaszewski
3386fb86ec gpiolib: fix reference leaks when removing GPIO chips still in use
After we remove a GPIO chip that still has some requested descriptors,
gpiod_free_commit() will fail and we will never put the references to the
GPIO device and the owning module in gpiod_free().

Rework this function to:
- not warn on desc == NULL as this is a use-case on which most free
  functions silently return
- put the references to desc->gdev and desc->gdev->owner unconditionally
  so that the release callback actually gets called when the remaining
  references are dropped by external GPIO users

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2023-08-16 13:35:50 +02:00
Asmaa Mnebhi
55b2395e4e gpio: mmio: handle "ngpios" properly in bgpio_init()
bgpio_init() uses "sz" argument to populate ngpio, which is not
accurate. Instead, read the "ngpios" property from the DT and if it
doesn't exist, use the "sz" argument. With this change, drivers no
longer need to overwrite the ngpio variable after calling bgpio_init().

If the "ngpios" property is specified, bgpio_bits is calculated
as the round up value of ngpio. At the moment, the only requirement
specified is that the round up value must be a multiple of 8 but
it should also be a power of 2 because we provide accessors based
on the bank size in bgpio_setup_accessors().

Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2023-07-18 20:59:25 +02:00
Andy Shevchenko
eec349dbe4 gpiolib: Replace open coded gpiochip_irqchip_add_allocated_domain()
Replace open coded variant of gpiochip_irqchip_add_allocated_domain()
in gpiochip_add_irqchip().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2023-07-10 11:29:47 +02:00
Andy Shevchenko
081bfdb303 gpiolib: Split out gpiochip_irqchip_add_allocated_domain() helper
The gpiochip_irqchip_add_allocated_domain() can be used
in another place in the code.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2023-07-10 11:29:45 +02:00