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authorWolfram Sang <wsa+renesas@sang-engineering.com>2016-04-12 18:00:53 +0200
committerLinus Walleij <linus.walleij@linaro.org>2016-04-15 16:04:32 +0200
commitc686090f14e0673f9b1a3aec316098742f8e003c (patch)
tree76406006013a8b30a82df22bd8632f12347b7ac5 /Documentation/devicetree/bindings/power/reset
parent35b3fc8876ef927885f68e481efc049285d07e53 (diff)
gpio/reset: move gpio-{poweroff|restart} DT doc to proper place
I did only find them after a fuzzy search, so let them be where one would expect them. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-By: Sebastian Reichel <sre@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'Documentation/devicetree/bindings/power/reset')
-rw-r--r--Documentation/devicetree/bindings/power/reset/gpio-poweroff.txt36
-rw-r--r--Documentation/devicetree/bindings/power/reset/gpio-restart.txt54
2 files changed, 90 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/power/reset/gpio-poweroff.txt b/Documentation/devicetree/bindings/power/reset/gpio-poweroff.txt
new file mode 100644
index 000000000000..d4eab9227ea4
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/reset/gpio-poweroff.txt
@@ -0,0 +1,36 @@
+Driver a GPIO line that can be used to turn the power off.
+
+The driver supports both level triggered and edge triggered power off.
+At driver load time, the driver will request the given gpio line and
+install a pm_power_off handler. If the optional properties 'input' is
+not found, the GPIO line will be driven in the inactive
+state. Otherwise its configured as an input.
+
+When the pm_power_off is called, the gpio is configured as an output,
+and drive active, so triggering a level triggered power off
+condition. This will also cause an inactive->active edge condition, so
+triggering positive edge triggered power off. After a delay of 100ms,
+the GPIO is set to inactive, thus causing an active->inactive edge,
+triggering negative edge triggered power off. After another 100ms
+delay the GPIO is driver active again. If the power is still on and
+the CPU still running after a 3000ms delay, a WARN_ON(1) is emitted.
+
+Required properties:
+- compatible : should be "gpio-poweroff".
+- gpios : The GPIO to set high/low, see "gpios property" in
+ Documentation/devicetree/bindings/gpio/gpio.txt. If the pin should be
+ low to power down the board set it to "Active Low", otherwise set
+ gpio to "Active High".
+
+Optional properties:
+- input : Initially configure the GPIO line as an input. Only reconfigure
+ it to an output when the pm_power_off function is called. If this optional
+ property is not specified, the GPIO is initialized as an output in its
+ inactive state.
+
+Examples:
+
+gpio-poweroff {
+ compatible = "gpio-poweroff";
+ gpios = <&gpio 4 0>;
+};
diff --git a/Documentation/devicetree/bindings/power/reset/gpio-restart.txt b/Documentation/devicetree/bindings/power/reset/gpio-restart.txt
new file mode 100644
index 000000000000..af3701bc15c4
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/reset/gpio-restart.txt
@@ -0,0 +1,54 @@
+Drive a GPIO line that can be used to restart the system from a restart
+handler.
+
+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]
+
+Examples:
+
+gpio-restart {
+ compatible = "gpio-restart";
+ gpios = <&gpio 4 0>;
+ priority = <128>;
+ active-delay = <100>;
+ inactive-delay = <100>;
+ wait-delay = <3000>;
+};