linux-toradex.git/include/linux/gpio/machine.h, branch v5.12-rc7

gpio: aggregator: Use compound literal from the header

2021-02-15T10:43:32+00:00

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 
Reviewed-by: Geert Uytterhoeven

gpiolib: Add support for GPIO lookup by line name

2020-05-18T08:12:42+00:00

Currently a GPIO lookup table can only refer to a specific GPIO by a
tuple, consisting of a GPIO controller label and a GPIO offset inside
the controller.

However, a GPIO may also carry a line name, defined by DT or ACPI.
If present, the line name is the most use-centric way to refer to a
GPIO.  Hence add support for looking up GPIOs by line name.
Note that there is no guarantee that GPIO line names are globally
unique, so this will use the first match found.

Implement this by reusing the existing gpiod_lookup infrastructure.
Rename gpiod_lookup.chip_label to gpiod_lookup.key, to make it clear
that this field can have two meanings, and update the kerneldoc and
GPIO_LOOKUP*() macros.

Signed-off-by: Geert Uytterhoeven 
Tested-by: Eugeniu Rosca 
Reviewed-by: Ulrich Hecht 
Reviewed-by: Eugeniu Rosca 
Link: https://lore.kernel.org/r/20200511145257.22970-4-geert+renesas@glider.be
Signed-off-by: Linus Walleij

gpio: Add comments on #if/#else/#endif

2019-06-27T14:56:50+00:00

Improve readability a bit by commenting #if/#else/#endif statements
with the checked preprocessor symbols.

Signed-off-by: Enrico Weigelt 
Signed-off-by: Linus Walleij

gpiolib: Introduce GPIO_LOOKUP_FLAGS_DEFAULT

2019-04-23T08:55:10+00:00

Since GPIO library operates with enumerator when it's subject to handle
the GPIO lookup flags, it will be better to clearly see what default means.

Thus, introduce GPIO_LOOKUP_FLAGS_DEFAULT entry to describe
the default assumptions.

While here, replace 0 by newly introduced constant.

Signed-off-by: Andy Shevchenko 
Reviewed-by: Mika Westerberg 
Signed-off-by: Linus Walleij

gpiolib: Make use of enum gpio_lookup_flags consistent

2019-04-23T08:55:07+00:00

The library uses enum gpio_lookup_flags to define the possible
characteristics of GPIO pin. Since enumerator listed only individual
bits the common use of it is in a form of a bitmask of
gpio_lookup_flags GPIO_* values. The more correct type for this is
unsigned long.

Due to above convert all users to use unsigned long instead of
enum gpio_lookup_flags except enumerator definition.

While here, make field and parameter descriptions consistent as well.

Suggested-by: Mika Westerberg 
Signed-off-by: Andy Shevchenko 
Reviewed-by: Mika Westerberg 
Signed-off-by: Linus Walleij

gpiolib: Indent entry values of enum gpio_lookup_flags

2019-04-23T08:54:42+00:00

Indent entry values in the enum gpio_lookup_flags for better readability.

No functional change.

Signed-off-by: Andy Shevchenko 
Acked-by: Hans de Goede 
Reviewed-by: Mika Westerberg 
Signed-off-by: Linus Walleij

gpio: add core support for pull-up/pull-down configuration

2019-02-13T08:10:14+00:00

This commit adds support for configuring the pull-up and pull-down
resistors available in some GPIO controllers. While configuring
pull-up/pull-down is already possible through the pinctrl subsystem,
some GPIO controllers, especially simple ones such as GPIO expanders
on I2C, don't have any pinmuxing capability and therefore do not use
the pinctrl subsystem.

This commit implements the GPIO_PULL_UP and GPIO_PULL_DOWN flags,
which can be used from the Device Tree, to enable a pull-up or
pull-down resistor on a given GPIO.

The flag is simply propagated all the way to the core GPIO subsystem,
where it is used to call the gpio_chip ->set_config callback with the
appropriate existing PIN_CONFIG_BIAS_* values.

Signed-off-by: Thomas Petazzoni 
Signed-off-by: Linus Walleij

gpiolib: add hogs support for machine code

2018-05-16T12:35:24+00:00

Board files constitute a significant part of the users of the legacy
GPIO framework. In many cases they only export a line and set its
desired value. We could use GPIO hogs for that like we do for DT and
ACPI but there's no support for that in machine code.

This patch proposes to extend the machine.h API with support for
registering hog tables in board files.

Signed-off-by: Bartosz Golaszewski 
Signed-off-by: Linus Walleij

gpio: gpiolib: Generalise state persistence beyond sleep

2017-12-02T21:42:34+00:00

General support for state persistence is added to gpiolib with the
introduction of a new pinconf parameter to propagate the request to
hardware. The existing persistence support for sleep is adapted to
include hardware support if the GPIO driver provides it. Persistence
continues to be enabled by default; in-kernel consumers can opt out, but
userspace (currently) does not have a choice.

The *_SLEEP_MAY_LOSE_VALUE and *_SLEEP_MAINTAIN_VALUE symbols are
renamed, dropping the SLEEP prefix to reflect that the concept is no
longer sleep-specific.  I feel that renaming to just *_MAY_LOSE_VALUE
could initially be misinterpreted, so I've further changed the symbols
to *_TRANSITORY and *_PERSISTENT to address this.

The sysfs interface is modified only to keep consistency with the
chardev interface in enforcing persistence for userspace exports.

Signed-off-by: Andrew Jeffery 
Reviewed-by: Charles Keepax 
Acked-by: Rob Herring 
Signed-off-by: Linus Walleij

Merge tag 'gpio-v4.15-1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

2017-11-15T01:23:44+00:00

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for the v4.15 kernel cycle:

  Core:

   - Fix the semantics of raw GPIO to actually be raw. No inversion
     semantics as before, but also no open draining, and allow the raw
     operations to affect lines used for interrupts as the caller
     supposedly knows what they are doing if they are getting the big
     hammer.

   - Rewrote the __inner_function() notation calls to names that make
     more sense. I just find this kind of code disturbing.

   - Drop the .irq_base() field from the gpiochip since now all IRQs are
     mapped dynamically. This is nice.

   - Support for .get_multiple() in the core driver API. This allows us
     to read several GPIO lines with a single register read. This has
     high value for some usecases: it can be used to create
     oscilloscopes and signal analyzers and other things that rely on
     reading several lines at exactly the same instant. Also a generally
     nice optimization. This uses the new assign_bit() macro from the
     bitops lib that was ACKed by Andrew Morton and is implemented for
     two drivers, one of them being the generic MMIO driver so everyone
     using that will be able to benefit from this.

   - Do not allow requests of Open Drain and Open Source setting of a
     GPIO line simultaneously. If the hardware actually supports
     enabling both at the same time the electrical result would be
     disastrous.

   - A new interrupt chip core helper. This will be helpful to deal with
     "banked" GPIOs, which means GPIO controllers with several logical
     blocks of GPIO inside them. This is several gpiochips per device in
     the device model, in contrast to the case when there is a 1-to-1
     relationship between a device and a gpiochip.

  New drivers:

   - Maxim MAX3191x industrial serializer, a very interesting piece of
     professional I/O hardware.

   - Uniphier GPIO driver. This is the GPIO block from the recent
     Socionext (ex Fujitsu and Panasonic) platform.

   - Tegra 186 driver. This is based on the new banked GPIO
     infrastructure.

  Other improvements:

   - Some documentation improvements.

   - Wakeup support for the DesignWare DWAPB GPIO controller.

   - Reset line support on the DesignWare DWAPB GPIO controller.

   - Several non-critical bug fixes and improvements for the Broadcom
     BRCMSTB driver.

   - Misc non-critical bug fixes like exotic errorpaths, removal of dead
     code etc.

   - Explicit comments on fall-through switch() statements"

* tag 'gpio-v4.15-1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (65 commits)
  gpio: tegra186: Remove tegra186_gpio_lock_class
  gpio: rcar: Add r8a77995 (R-Car D3) support
  pinctrl: bcm2835: Fix some merge fallout
  gpio: Fix undefined lock_dep_class
  gpio: Automatically add lockdep keys
  gpio: Introduce struct gpio_irq_chip.first
  gpio: Disambiguate struct gpio_irq_chip.nested
  gpio: Add Tegra186 support
  gpio: Export gpiochip_irq_{map,unmap}()
  gpio: Implement tighter IRQ chip integration
  gpio: Move lock_key into struct gpio_irq_chip
  gpio: Move irq_valid_mask into struct gpio_irq_chip
  gpio: Move irq_nested into struct gpio_irq_chip
  gpio: Move irq_chained_parent to struct gpio_irq_chip
  gpio: Move irq_default_type to struct gpio_irq_chip
  gpio: Move irq_handler to struct gpio_irq_chip
  gpio: Move irqdomain into struct gpio_irq_chip
  gpio: Move irqchip into struct gpio_irq_chip
  gpio: Introduce struct gpio_irq_chip
  pinctrl: armada-37xx: remove unused variable
  ...