dt-bindings: gpio: Document GPIOs via Moxtet bus

This patch adds documentation of the device tree bindings for GPIOs
on the devices connected via Moxtet bus.

Link: https://lore.kernel.org/r/20190812161118.21476-6-marek.behun@nic.cz
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

diff --git a/Documentation/devicetree/bindings/gpio/gpio-moxtet.txt b/Documentation/devicetree/bindings/gpio/gpio-moxtet.txt
new file mode 100644 (file)
index 0000000..410759d
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/gpio-moxtet.txt
@@ -0,0 +1,18 @@
+Turris Mox Moxtet GPIO expander via Moxtet bus
+
+Required properties:
+ - compatible          : Should be "cznic,moxtet-gpio".
+ - gpio-controller     : Marks the device node as a GPIO controller.
+ - #gpio-cells         : Should be two. For consumer use see gpio.txt.
+
+Other properties are required for a Moxtet bus device, please refer to
+Documentation/devicetree/bindings/bus/moxtet.txt.
+
+Example:
+
+       moxtet_sfp: gpio@0 {
+               compatible = "cznic,moxtet-gpio";
+               gpio-controller;
+               #gpio-cells = <2>;
+               reg = <0>;
+       }

diff --git a/MAINTAINERS b/MAINTAINERS
index a71ab252ad7ecdfa31ccd9f5725e381072a2fae5..0872e4cb98efe7851e12ce7541cbd3e6cb5ba812 100644 (file)
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1633,6 +1633,7 @@ S:        Maintained
 F:     Documentation/ABI/testing/debugfs-moxtet
 F:     Documentation/ABI/testing/sysfs-bus-moxtet-devices
 F:     Documentation/devicetree/bindings/bus/moxtet.txt
+F:     Documentation/devicetree/bindings/gpio/gpio-moxtet.txt
 F:     include/linux/moxtet.h
 F:     drivers/bus/moxtet.c
 F:     drivers/gpio/gpio-moxtet.c