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authorHeiko Stuebner <heiko@sntech.de>2012-09-07 06:49:47 +0900
committerKukjin Kim <kgene.kim@samsung.com>2012-09-07 14:02:50 +0900
commit172c6a13653ac8cd6a231293b87c93821e90c1d6 (patch)
treee8921c1272a316a0c1465a425b29631127589a50 /Documentation/devicetree/bindings/gpio/gpio-samsung.txt
parent4cbe5a555fa58a79b6ecbb6c531b8bab0650778d (diff)
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 <heiko@sntech.de> Reviewed-by: Thomas Abraham <thomas.abraham@linaro.org> Acked-by: Linus Walleij <linus.walleij@linaro.org> [kgene.kim@samsung.com: fixed build error] Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Diffstat (limited to 'Documentation/devicetree/bindings/gpio/gpio-samsung.txt')
-rw-r--r--Documentation/devicetree/bindings/gpio/gpio-samsung.txt43
1 files changed, 43 insertions, 0 deletions
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;
+ };