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author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-12-14 23:05:05 +0100 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-12-14 23:05:05 +0100 |
commit | 980f3c344ff1cb4a8be9a169c6bde2dc74ca6288 (patch) | |
tree | f7b22006dec2cebed697b0a2c6701ca16c58c7a2 /Documentation/gpio/consumer.txt | |
parent | Merge git://git.kvack.org/~bcrl/aio-next (diff) | |
parent | gpio: mcp23s08: fix up compilation error (diff) | |
download | linux-980f3c344ff1cb4a8be9a169c6bde2dc74ca6288.tar.xz linux-980f3c344ff1cb4a8be9a169c6bde2dc74ca6288.zip |
Merge tag 'gpio-v3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull take two of the GPIO updates:
"Same stuff as last time, now with a fixup patch for the previous
compile error plus I ran a few extra rounds of compile-testing.
This is the bulk of GPIO changes for the v3.19 series:
- A new API that allows setting more than one GPIO at the time. This
is implemented for the new descriptor-based API only and makes it
possible to e.g. toggle a clock and data line at the same time, if
the hardware can do this with a single register write. Both
consumers and drivers need new calls, and the core will fall back
to driving individual lines where needed. Implemented for the
MPC8xxx driver initially
- Patched the mdio-mux-gpio and the serial mctrl driver that drives
modems to use the new multiple-setting API to set several signals
simultaneously
- Get rid of the global GPIO descriptor array, and instead allocate
descriptors dynamically for each GPIO on a certain GPIO chip. This
moves us closer to getting rid of the limitation of using the
global, static GPIO numberspace
- New driver and device tree bindings for 74xx ICs
- New driver and device tree bindings for the VF610 Vybrid
- Support the RCAR r8a7793 and r8a7794
- Guidelines for GPIO device tree bindings trying to get things a bit
more strict with the advent of combined device properties
- Suspend/resume support for the MVEBU driver
- A slew of minor fixes and improvements"
* tag 'gpio-v3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (33 commits)
gpio: mcp23s08: fix up compilation error
gpio: pl061: document gpio-ranges property for bindings file
gpio: pl061: hook request if gpio-ranges avaiable
gpio: mcp23s08: Add option to configure IRQ output polarity as active high
gpio: fix deferred probe detection for legacy API
serial: mctrl_gpio: use gpiod_set_array function
mdio-mux-gpio: Use GPIO descriptor interface and new gpiod_set_array function
gpio: remove const modifier from gpiod_get_direction()
gpio: remove gpio_descs global array
gpio: mxs: implement get_direction callback
gpio: em: Use dynamic allocation of GPIOs
gpio: Check if base is positive before calling gpio_is_valid()
gpio: mcp23s08: Add simple IRQ support for SPI devices
gpio: mcp23s08: request a shared interrupt
gpio: mcp23s08: Do not free unrequested interrupt
gpio: rcar: Add r8a7793 and r8a7794 support
gpio-mpc8xxx: add mpc8xxx_gpio_set_multiple function
gpiolib: allow simultaneous setting of multiple GPIO outputs
gpio: mvebu: add suspend/resume support
gpio: gpio-davinci: remove duplicate check on resource
..
Diffstat (limited to 'Documentation/gpio/consumer.txt')
-rw-r--r-- | Documentation/gpio/consumer.txt | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/Documentation/gpio/consumer.txt b/Documentation/gpio/consumer.txt index 859918db36b8..d85fbae451ea 100644 --- a/Documentation/gpio/consumer.txt +++ b/Documentation/gpio/consumer.txt @@ -199,6 +199,33 @@ The active-low state of a GPIO can also be queried using the following call: Note that these functions should only be used with great moderation ; a driver should not have to care about the physical line level. + +Set multiple GPIO outputs with a single function call +----------------------------------------------------- +The following functions set the output values of an array of GPIOs: + + void gpiod_set_array(unsigned int array_size, + struct gpio_desc **desc_array, + int *value_array) + void gpiod_set_raw_array(unsigned int array_size, + struct gpio_desc **desc_array, + int *value_array) + void gpiod_set_array_cansleep(unsigned int array_size, + struct gpio_desc **desc_array, + int *value_array) + void gpiod_set_raw_array_cansleep(unsigned int array_size, + struct gpio_desc **desc_array, + int *value_array) + +The array can be an arbitrary set of GPIOs. The functions will try to set +GPIOs belonging to the same bank or chip simultaneously if supported by the +corresponding chip driver. In that case a significantly improved performance +can be expected. If simultaneous setting is not possible the GPIOs will be set +sequentially. +Note that for optimal performance GPIOs belonging to the same chip should be +contiguous within the array of descriptors. + + GPIOs mapped to IRQs -------------------- GPIO lines can quite often be used as IRQs. You can get the IRQ number |