summaryrefslogtreecommitdiff
path: root/Documentation/devicetree/bindings/gpio
diff options
context:
space:
mode:
authorLevin Du <djw@t-chip.com.cn>2018-07-31 08:59:19 +0300
committerLinus Walleij <linus.walleij@linaro.org>2018-08-07 00:46:55 +0300
commitcf2ff877a4eea5f5ad959050284eb93d5d2f803a (patch)
tree9bc792a851fe0f965bf1b530dbe12082ea45f818 /Documentation/devicetree/bindings/gpio
parent442af1403a2886f8f6d43f2f67f8a8b001e048d8 (diff)
downloadlinux-cf2ff877a4eea5f5ad959050284eb93d5d2f803a.tar.xz
gpio: syscon: rockchip: add GRF GPIO support for rk3328
In Rockchip RK3328, the output only GPIO_MUTE pin, originally for codec mute control, can also be used for general purpose. It is manipulated by the GRF_SOC_CON10 register in GRF. Aside from the GPIO_MUTE pin, the HDMI pins can also be set in the same way. Currently this GRF GPIO controller only supports the mute pin. If needed in the future, the HDMI pins support can also be added. Signed-off-by: Levin Du <djw@t-chip.com.cn> Reviewed-by: Rob Herring <robh@kernel.org> Reviewed-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'Documentation/devicetree/bindings/gpio')
-rw-r--r--Documentation/devicetree/bindings/gpio/rockchip,rk3328-grf-gpio.txt32
1 files changed, 32 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/gpio/rockchip,rk3328-grf-gpio.txt b/Documentation/devicetree/bindings/gpio/rockchip,rk3328-grf-gpio.txt
new file mode 100644
index 000000000000..f9231df17c2b
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/rockchip,rk3328-grf-gpio.txt
@@ -0,0 +1,32 @@
+Rockchip RK3328 GRF (General Register Files) GPIO controller.
+
+In Rockchip RK3328, the output only GPIO_MUTE pin, originally for codec mute
+control, can also be used for general purpose. It is manipulated by the
+GRF_SOC_CON10 register in GRF. Aside from the GPIO_MUTE pin, the HDMI pins can
+also be set in the same way.
+
+Currently this GPIO controller only supports the mute pin. If needed in the
+future, the HDMI pins support can also be added.
+
+Required properties:
+- compatible: Should contain "rockchip,rk3328-grf-gpio".
+- gpio-controller: Marks the device node as a gpio controller.
+- #gpio-cells: Should be 2. The first cell is the pin number and
+ the second cell is used to specify the gpio polarity:
+ 0 = Active high,
+ 1 = Active low.
+
+Example:
+
+ grf: syscon@ff100000 {
+ compatible = "rockchip,rk3328-grf", "syscon", "simple-mfd";
+
+ grf_gpio: grf-gpio {
+ compatible = "rockchip,rk3328-grf-gpio";
+ gpio-controller;
+ #gpio-cells = <2>;
+ };
+ };
+
+Note: The grf_gpio node should be declared as the child of the GRF (General
+Register File) node. The GPIO_MUTE pin is referred to as <&grf_gpio 0>.