From 172c6a13653ac8cd6a231293b87c93821e90c1d6 Mon Sep 17 00:00:00 2001 From: Heiko Stuebner Date: Fri, 7 Sep 2012 06:49:47 +0900 Subject: gpio: samsung: add devicetree init for s3c24xx arches Until now the EXYNOS-SoC was the only Samsung-SoC supporting the GPIOs via the device tree. This patch implements dt-support for the s3c24xx arches. The controllers contain only 3 cells, as the underlying gpio controller does not support controlling the drive strength on a gpio level. Tested with the gpio-keys driver on a s3c2416 based machine. Signed-off-by: Heiko Stuebner Reviewed-by: Thomas Abraham Acked-by: Linus Walleij [kgene.kim@samsung.com: fixed build error] Signed-off-by: Kukjin Kim --- .../devicetree/bindings/gpio/gpio-samsung.txt | 43 ++++++++++++++++++++++ 1 file changed, 43 insertions(+) (limited to 'Documentation/devicetree') diff --git a/Documentation/devicetree/bindings/gpio/gpio-samsung.txt b/Documentation/devicetree/bindings/gpio/gpio-samsung.txt index 5375625e8cd2..f1e5dfecf55d 100644 --- a/Documentation/devicetree/bindings/gpio/gpio-samsung.txt +++ b/Documentation/devicetree/bindings/gpio/gpio-samsung.txt @@ -39,3 +39,46 @@ Example: #gpio-cells = <4>; gpio-controller; }; + + +Samsung S3C24XX GPIO Controller + +Required properties: +- compatible: Compatible property value should be "samsung,s3c24xx-gpio". + +- reg: Physical base address of the controller and length of memory mapped + region. + +- #gpio-cells: Should be 3. The syntax of the gpio specifier used by client nodes + should be the following with values derived from the SoC user manual. + <[phandle of the gpio controller node] + [pin number within the gpio controller] + [mux function] + [flags and pull up/down] + + Values for gpio specifier: + - Pin number: depending on the controller a number from 0 up to 15. + - Mux function: Depending on the SoC and the gpio bank the gpio can be set + as input, output or a special function + - Flags and Pull Up/Down: the values to use differ for the individual SoCs + example S3C2416/S3C2450: + 0 - Pull Up/Down Disabled. + 1 - Pull Down Enabled. + 2 - Pull Up Enabled. + Bit 16 (0x00010000) - Input is active low. + Consult the user manual for the correct values of Mux and Pull Up/Down. + +- gpio-controller: Specifies that the node is a gpio controller. +- #address-cells: should be 1. +- #size-cells: should be 1. + +Example: + + gpa: gpio-controller@56000000 { + #address-cells = <1>; + #size-cells = <1>; + compatible = "samsung,s3c24xx-gpio"; + reg = <0x56000000 0x10>; + #gpio-cells = <3>; + gpio-controller; + }; -- cgit v1.2.3-59-g8ed1b