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authorLinus Torvalds <torvalds@linux-foundation.org>2016-05-17 17:39:42 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-05-17 17:39:42 -0700
commit1eccc6e1529ec7ad1cebbd2c97ceb2a1a39f7d76 (patch)
tree725aff1150489e706b2b8b854b195a7a50dc6501 /Documentation/devicetree/bindings/power
parentdcc4c2f61cdc7e0ab61b25b8d28205302497a8c4 (diff)
parentd30a2b47d4c2b75573d93f60655d48ba8e3ed2b3 (diff)
Merge tag 'gpio-v4.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO updates from Linus Walleij: "This is the bulk of GPIO changes for kernel cycle v4.7: Core infrastructural changes: - Support for natively single-ended GPIO driver stages. This means that if the hardware has registers to configure open drain or open source configuration, we use that rather than (as we did before) try to emulate it by switching the line to an input to get high impedance. This is also documented throughly in Documentation/gpio/driver.txt for those of you who did not understand one word of what I just wrote. - Start to do away with the unnecessarily complex and unitelligible ARCH_REQUIRE_GPIOLIB and ARCH_WANT_OPTIONAL_GPIOLIB, another evolutional artifact from the time when the GPIO subsystem was unmaintained. Archs can now just select GPIOLIB and be done with it, cleanups to arches will trickle in for the next kernel. Some minor archs ACKed the changes immediately so these are included in this pull request. - Advancing the use of the data pointer inside the GPIO device for storing driver data by switching the PowerPC, Super-H Unicore and a few other subarches or subsystem drivers in ALSA SoC, Input, serial, SSB, staging etc to use it. - The initialization now reads the input/output state of the GPIO lines, so that each GPIO descriptor knows - if this callback is implemented - whether the line is input or output. This also reflects nicely in userspace "lsgpio". - It is now possible to name GPIO producer names, line names, from the device tree. (Platform data has been supported for a while). I bet we will get a similar mechanism for ACPI one of those days. This makes is possible to get sensible producer names for e.g. GPIO rails in "lsgpio" in userspace. New drivers: - New driver for the Loongson1. - The XLP driver now supports Broadcom Vulcan ARM64. - The IT87 driver now supports IT8620 and IT8628. - The PCA953X driver now supports Galileo Gen2. Driver improvements: - MCP23S08 was switched to use the gpiolib irqchip helpers and now also suppors level-triggered interrupts. - 74x164 and RCAR now supports the .set_multiple() callback - AMDPT was converted to use generic GPIO. - TC3589x, TPS65218, SX150X, F7188X, MENZ127, VX855, WM831X, WM8994 support the new single ended callback for open drain and in some cases open source. - Implement the .get_direction() callback for a few more drivers like PL061, Xgene. Cleanups: - Paul Gortmaker combed through the drivers and de-modularized those who are not really modules. - Move the GPIO poweroff DT bindings to the power subdir where they belong. - Rename gpio-generic.c to gpio-mmio.c, which is much more to the point. That's what it is handling, nothing more, nothing less" * tag 'gpio-v4.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (126 commits) MIPS: do away with ARCH_[WANT_OPTIONAL|REQUIRE]_GPIOLIB gpio: zevio: make it explicitly non-modular gpio: timberdale: make it explicitly non-modular gpio: stmpe: make it explicitly non-modular gpio: sodaville: make it explicitly non-modular pinctrl: sh-pfc: Let gpio_chip.to_irq() return zero on error gpio: dwapb: Add ACPI device ID for DWAPB GPIO controller on X-Gene platforms gpio: dt-bindings: add wd,mbl-gpio bindings gpio: of: make it possible to name GPIO lines gpio: make gpiod_to_irq() return negative for NO_IRQ gpio: xgene: implement .get_direction() gpio: xgene: Enable ACPI support for X-Gene GFC GPIO driver gpio: tegra: Implement gpio_get_direction callback gpio: set up initial state from .get_direction() gpio: rename gpio-generic.c into gpio-mmio.c gpio: generic: fix GPIO_GENERIC_PLATFORM is set to module case gpio: dwapb: add gpio-signaled acpi event support gpio: dwapb: convert device node to fwnode gpio: dwapb: remove name from dwapb_port_property gpio/qoriq: select IRQ_DOMAIN ...
Diffstat (limited to 'Documentation/devicetree/bindings/power')
-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>;
+};