linux-stable.git/Documentation/gpio, branch v3.17

Documentation: gpio: documentation for optional getters functions

2014-08-29T06:53:53+00:00

Add a mention about the _optional variants of (devm_)gpiod_get*().

Signed-off-by: Alexandre Courbot 
Signed-off-by: Linus Walleij

gpio: add flags argument to gpiod_get*() functions

2014-07-28T10:28:05+00:00

The huge majority of GPIOs have their direction and initial value set
right after being obtained by one of the gpiod_get() functions. The
integer GPIO API had gpio_request_one() that took a convenience flags
parameter allowing to specify an direction and value applied to the
returned GPIO. This feature greatly simplifies client code and ensures
errors are always handled properly.

A similar feature has been requested for the gpiod API. Since setting
the direction of a GPIO is so often the very next action done after
obtaining its descriptor, we prefer to extend the existing functions
instead of introducing new functions that would raise the
number of gpiod getters to 16 (!).

The drawback of this approach is that all gpiod clients need to be
updated. To limit the pain, temporary macros are introduced that allow
gpiod_get*() to be called with or without the extra flags argument. They
will be removed once all consumer code has been updated.

Signed-off-by: Alexandre Courbot 
Reviewed-by: Mark Brown 
Signed-off-by: Linus Walleij

gpio: split gpiod board registration into machine header

2014-07-28T10:23:35+00:00

As per example from the regulator subsystem: put all defines and
functions related to registering board info for GPIO descriptors
into a separate  header.

Cc: Andrew Victor 
Cc: Nicolas Ferre 
Cc: Jean-Christophe Plagniol-Villard 
Cc: Ralf Baechle 
Cc: Thierry Reding 
Acked-by: Stephen Warren 
Reviewed-by: Alexandre Courbot 
Signed-off-by: Linus Walleij

gpiolib: Export gpiochip_request_own_desc and gpiochip_free_own_desc

2014-07-24T08:25:00+00:00

Both functions were introduced to let gpio drivers request their own
gpio pins. Without exporting the functions, this can however only be
used by gpio drivers built into the kernel.

Secondary impact is that the functions can not currently be used by
platform initialization code associated with the gpio-pca953x driver.
This code permits auto-export of gpio pins through platform data, but
if this functionality is used, the module can no longer be unloaded due
to the problem solved with the introduction of gpiochip_request_own_desc
and gpiochip_free_own_desc.

Export both function so they can be used from modules and from
platform initialization code.

Reviewed-by: Alexandre Courbot 
Reviewed-by: Mika Westerberg 
Signed-off-by: Guenter Roeck 
Signed-off-by: Linus Walleij

gpio: remove gpiod_lock/unlock_as_irq()

2014-07-23T15:43:24+00:00

gpio_lock/unlock_as_irq() are working with (chip, offset) arguments and
are thus not using the old integer namespace. Therefore, there is no
reason to have gpiod variants of these functions working with
descriptors, especially since the (chip, offset) tuple is more suitable
to the users of these functions (GPIO drivers, whereas GPIO descriptors
are targeted at GPIO consumers).

Signed-off-by: Alexandre Courbot 
Signed-off-by: Linus Walleij

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next

2014-06-04T15:50:34+00:00

Pull trivial tree changes from Jiri Kosina:
 "Usual pile of patches from trivial tree that make the world go round"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits)
  staging: go7007: remove reference to CONFIG_KMOD
  aic7xxx: Remove obsolete preprocessor define
  of: dma: doc fixes
  doc: fix incorrect formula to calculate CommitLimit value
  doc: Note need of bc in the kernel build from 3.10 onwards
  mm: Fix printk typo in dmapool.c
  modpost: Fix comment typo "Modules.symvers"
  Kconfig.debug: Grammar s/addition/additional/
  wimax: Spelling s/than/that/, wording s/destinatary/recipient/
  aic7xxx: Spelling s/termnation/termination/
  arm64: mm: Remove superfluous "the" in comment
  of: Spelling s/anonymouns/anonymous/
  dma: imx-sdma: Spelling s/determnine/determine/
  ath10k: Improve grammar in comments
  ath6kl: Spelling s/determnine/determine/
  of: Improve grammar for of_alias_get_id() documentation
  drm/exynos: Spelling s/contro/control/
  radio-bcm2048.c: fix wrong overflow check
  doc: printk-formats: do not mention casts for u64/s64
  doc: spelling error changes
  ...

doc: spelling error changes

2014-05-05T13:32:05+00:00

Fixed multiple spelling errors.

Acked-by: Randy Dunlap 
Signed-off-by: Carlos E. Garcia 
Signed-off-by: Jiri Kosina

gpio: document gpio irqchips a bit more, describe helpers

2014-04-28T19:35:07+00:00

This adds some documentation about the GPIO irqchips, what types
exist etc.

Acked-by: Alexandre Courbot 
Signed-off-by: Linus Walleij

gpio: make gpiod_direction_output take a logical value

2014-02-07T08:47:02+00:00

The documentation was not clear about whether
gpio_direction_output should take a logical value or the physical
level on the output line, i.e. whether the ACTIVE_LOW status
would be taken into account.

This converts gpiod_direction_output to use the logical level
and adds a new gpiod_direction_output_raw for the raw value.

Signed-off-by: Philipp Zabel 
Reviewed-by: Alexandre Courbot 
Signed-off-by: Linus Walleij

gpio: document how to make combined GPIO+irqchip drivers

2014-02-03T08:11:57+00:00

Write a few words on how GPIO drivers supplying an irqchip should
be written.

Cc: Thomas Gleixner 
Signed-off-by: Linus Walleij