path: root/Documentation/devicetree/bindings/gpio
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authorLinus Torvalds <torvalds@linux-foundation.org>2014-10-15 06:56:23 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2014-10-15 06:56:23 +0200
commit50fa86172bec2769979b5eb0cd1a244391ae4bb0 (patch)
tree5fd4949b031e1362af8b226d6372da2604de13ff /Documentation/devicetree/bindings/gpio
parent6b0490816671b2f4126a99998c9bf3c8c0472de2 (diff)
parent7881c64716f3a7d60b325ed0ad4d15f49b474a43 (diff)
Merge tag 'for-v3.18' of git://git.infradead.org/battery-2.6
Pull power supply and reset updates from Sebastian Reichel: - Initial support for the following chips * max77836 (charger) * max14577 (charger) * bq27742 (battery gauge) * ltc2952 (poweroff) * stih416 (restart) * syscon-reboot (restart) * gpio-restart (restart) - cleanup of power supply core - misc fixes in power supply and reset drivers * tag 'for-v3.18' of git://git.infradead.org/battery-2.6: (48 commits) power: ab8500_fg: Fix build warning Documentation: charger: max14577: Update the date of introducing ABI power: reset: corrections for simple syscon reboot driver Documentation: power: reset: Add documentation for generic SYSCON reboot driver power: reset: Add generic SYSCON register mapped reset bq27x00_battery: Fix flag reading for bq27742 power: reset: use restart_notifier mechanism for msm-poweroff power: Add simple gpio-restart driver power: reset: st: Provide DT bindings for ST's Power Reset driver power: reset: Add restart functionality for STiH41x platforms power: charger-manager: Fix NULL pointer exception with missing cm-fuel-gauge power: max14577: Fix circular config SYSFS dependency power: gpio-charger: do not use gpio value directly power: max8925: Use of_get_child_by_name power: max8925: Fix NULL ptr dereference on memory allocation failure bq27x00_battery: Add support to bq27742 Documentation: charger: max14577: Document exported sysfs entry devicetree: mfd: max14577: Add device tree bindings document power: max17040: Add ID for MAX77836 Fuel Gauge block charger: max14577: Configure battery-dependent settings from DTS and sysfs ... Conflicts: drivers/power/reset/Kconfig drivers/power/reset/Makefile
Diffstat (limited to 'Documentation/devicetree/bindings/gpio')
1 files changed, 54 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/gpio/gpio-restart.txt b/Documentation/devicetree/bindings/gpio/gpio-restart.txt
new file mode 100644
index 000000000000..af3701bc15c4
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/gpio-restart.txt
@@ -0,0 +1,54 @@
+Drive a GPIO line that can be used to restart the system from a restart
+This binding supports level and edge triggered reset. At driver load
+time, the driver will request the given gpio line and install a restart
+handler. If the optional properties 'open-source' is not found, the GPIO line
+will be driven in the inactive state. Otherwise its not driven until
+the restart is initiated.
+When the system is restarted, the restart handler will be invoked in
+priority order. The gpio is configured as an output, and driven active,
+triggering a level triggered reset condition. This will also cause an
+inactive->active edge condition, triggering positive edge triggered
+reset. After a delay specified by active-delay, the GPIO is set to
+inactive, thus causing an active->inactive edge, triggering negative edge
+triggered reset. After a delay specified by inactive-delay, the GPIO
+is driven active again. After a delay specified by wait-delay, the
+restart handler completes allowing other restart handlers to be attempted.
+Required properties:
+- compatible : should be "gpio-restart".
+- gpios : The GPIO to set high/low, see "gpios property" in
+ Documentation/devicetree/bindings/gpio/gpio.txt. If the pin should be
+ low to reset the board set it to "Active Low", otherwise set
+ gpio to "Active High".
+Optional properties:
+- open-source : Treat the GPIO as being open source and defer driving
+ it to when the restart is initiated. If this optional property is not
+ specified, the GPIO is initialized as an output in its inactive state.
+- priority : A priority ranging from 0 to 255 (default 128) according to
+ the following guidelines:
+ 0: Restart handler of last resort, with limited restart
+ capabilities
+ 128: Default restart handler; use if no other restart handler is
+ expected to be available, and/or if restart functionality is
+ sufficient to restart the entire system
+ 255: Highest priority restart handler, will preempt all other
+ restart handlers
+- active-delay: Delay (default 100) to wait after driving gpio active [ms]
+- inactive-delay: Delay (default 100) to wait after driving gpio inactive [ms]
+- wait-delay: Delay (default 3000) to wait after completing restart
+ sequence [ms]
+gpio-restart {
+ compatible = "gpio-restart";
+ gpios = <&gpio 4 0>;
+ priority = <128>;
+ active-delay = <100>;
+ inactive-delay = <100>;
+ wait-delay = <3000>;

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