Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2071835
Tested: This is one of a series of patch sets to enable Arm SystemReady IR
support in the kernel for NXP i.MX8 platforms. This set updates GPIO
support. It has been tested via simple boot tests and by using the
kernel GPIO tools to verify pins are being identified and can be used.
commit 2cba05451a6d0c703bb74f1a250691404f27c4f1
Author: Geert Uytterhoeven <geert+renesas@glider.be>
Date: Mon Jan 31 11:35:53 2022 +0100
gpio: aggregator: Fix calling into sleeping GPIO controllers
If the parent GPIO controller is a sleeping controller (e.g. a GPIO
controller connected to I2C), getting or setting a GPIO triggers a
might_sleep() warning. This happens because the GPIO Aggregator takes
the can_sleep flag into account only for its internal locking, not for
calling into the parent GPIO controller.
Fix this by using the gpiod_[gs]et*_cansleep() APIs when calling into a
sleeping GPIO controller.
Reported-by: Mikko Salomäki <ms@datarespons.se>
Fixes: 828546e242 ("gpio: Add GPIO Aggregator")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
(cherry picked from commit 2cba05451a6d0c703bb74f1a250691404f27c4f1)
Signed-off-by: Al Stone <ahs3@redhat.com>
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2071835
Tested: This is one of a series of patch sets to enable Arm SystemReady IR
support in the kernel for NXP i.MX8 platforms. This set updates GPIO
support. It has been tested via simple boot tests and by using the
kernel GPIO tools to verify pins are being identified and can be used.
commit a00128dfc8fc0cc8848d9168d6e7cfff99bd46f0
Author: Geert Uytterhoeven <geert+renesas@glider.be>
Date: Fri Dec 3 15:06:44 2021 +0100
gpio: aggregator: Add interrupt support
Currently the GPIO Aggregator does not support interrupts. This means
that kernel drivers going from a GPIO to an IRQ using gpiod_to_irq(),
and userspace applications using line events do not work.
Add interrupt support by providing a gpio_chip.to_irq() callback, which
just calls into the parent GPIO controller.
Note that this does not implement full interrupt controller (irq_chip)
support, so using e.g. gpio-keys with "interrupts" instead of "gpios"
still does not work.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
(cherry picked from commit a00128dfc8fc0cc8848d9168d6e7cfff99bd46f0)
Signed-off-by: Al Stone <ahs3@redhat.com>
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2071835
Tested: This is one of a series of patch sets to enable Arm SystemReady IR
support in the kernel for NXP i.MX8 platforms. This set updates GPIO
support. It has been tested via simple boot tests and by using the
kernel GPIO tools to verify pins are being identified and can be used.
commit aa4858eb8264358e9c18c3ad79d6ab4fdc71e0c2
Author: Geert Uytterhoeven <geert+renesas@glider.be>
Date: Mon Oct 4 14:45:45 2021 +0200
gpio: aggregator: Wrap access to gpiochip_fwd.tmp[]
The tmp[] member of the gpiochip_fwd structure is used to store both the
temporary values bitmap and the desc pointers for operations on multiple
GPIOs. As both are arrays with sizes unknown at compile-time, accessing
them requires offset calculations, which are currently duplicated in
gpio_fwd_get_multiple() and gpio_fwd_set_multiple().
Introduce (a) accessors for both arrays and (b) a macro to calculate the
needed storage size. This confines the layout of the tmp[] member into
a single spot, to ease maintenance.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
(cherry picked from commit aa4858eb8264358e9c18c3ad79d6ab4fdc71e0c2)
Signed-off-by: Al Stone <ahs3@redhat.com>
cmdline library provides next_arg() helper to traverse over parameters
and their values given in command line. Replace custom approach in the driver
by it.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Instead of doing it in place, convert GPIO_LOOKUP_IDX() and GPIO_HOG()
to be compund literals that's allow to use them as rvalue in assignments.
Due to above conversion, use compound literal from the header
in the gpio-aggregator.c.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
We already have a nice helper called get_options() which can be used
to validate the input format. Replace isrange() by using it.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Sparse can't see locking scheme used in ->get_multiple() and
->set_multiple() callbacks.
CHECK .../drivers/gpio/gpio-aggregator.c
.../spinlock.h:409:9: warning: context imbalance in 'gpio_fwd_get_multiple' - unexpected unlock
.../spinlock.h:409:9: warning: context imbalance in 'gpio_fwd_set_multiple' - unexpected unlock
Refactor them to have better readability and make Sparse happy.
Code size impact is +52 bytes with arm-linux-gnueabihf-gcc 7.5.0.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Replace the custom code to parse GPIO offsets and/or GPIO offset ranges
by a call to bitmap_parselist(), and an iteration over the returned bit
mask.
This should have no impact on the format of the configuration parameters
written to the "new_device" virtual file in sysfs.
Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200701114212.8520-3-geert+renesas@glider.be
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
In get_arg(), the variable start is pre-initialized, but overwritten
again in the first statement. Rework the assignment to not rely on
pre-initialization, to make the code easier to read.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200701114212.8520-2-geert+renesas@glider.be
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
GPIO controllers are exported to userspace using /dev/gpiochip*
character devices. Access control to these devices is provided by
standard UNIX file system permissions, on an all-or-nothing basis:
either a GPIO controller is accessible for a user, or it is not.
Currently no mechanism exists to control access to individual GPIOs.
Hence add a GPIO driver to aggregate existing GPIOs, and expose them as
a new gpiochip.
This supports the following use cases:
- Aggregating GPIOs using Sysfs
This is useful for implementing access control, and assigning a set
of GPIOs to a specific user or virtual machine.
- Generic GPIO Driver
This is useful for industrial control, where it can provide
userspace access to a simple GPIO-operated device described in DT,
cfr. e.g. spidev for SPI-operated devices.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Reviewed-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Link: https://lore.kernel.org/r/20200511145257.22970-5-geert+renesas@glider.be
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Al Stone
Andy Shevchenko
Geert Uytterhoeven