diff options
Diffstat (limited to 'Documentation/devicetree/bindings/gpio')
-rw-r--r-- | Documentation/devicetree/bindings/gpio/gpio-samsung.txt | 43 |
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: | |||
39 | #gpio-cells = <4>; | 39 | #gpio-cells = <4>; |
40 | gpio-controller; | 40 | gpio-controller; |
41 | }; | 41 | }; |
42 | |||
43 | |||
44 | Samsung S3C24XX GPIO Controller | ||
45 | |||
46 | Required properties: | ||
47 | - compatible: Compatible property value should be "samsung,s3c24xx-gpio". | ||
48 | |||
49 | - reg: Physical base address of the controller and length of memory mapped | ||
50 | region. | ||
51 | |||
52 | - #gpio-cells: Should be 3. The syntax of the gpio specifier used by client nodes | ||
53 | should be the following with values derived from the SoC user manual. | ||
54 | <[phandle of the gpio controller node] | ||
55 | [pin number within the gpio controller] | ||
56 | [mux function] | ||
57 | [flags and pull up/down] | ||
58 | |||
59 | Values for gpio specifier: | ||
60 | - Pin number: depending on the controller a number from 0 up to 15. | ||
61 | - Mux function: Depending on the SoC and the gpio bank the gpio can be set | ||
62 | as input, output or a special function | ||
63 | - Flags and Pull Up/Down: the values to use differ for the individual SoCs | ||
64 | example S3C2416/S3C2450: | ||
65 | 0 - Pull Up/Down Disabled. | ||
66 | 1 - Pull Down Enabled. | ||
67 | 2 - Pull Up Enabled. | ||
68 | Bit 16 (0x00010000) - Input is active low. | ||
69 | Consult the user manual for the correct values of Mux and Pull Up/Down. | ||
70 | |||
71 | - gpio-controller: Specifies that the node is a gpio controller. | ||
72 | - #address-cells: should be 1. | ||
73 | - #size-cells: should be 1. | ||
74 | |||
75 | Example: | ||
76 | |||
77 | gpa: gpio-controller@56000000 { | ||
78 | #address-cells = <1>; | ||
79 | #size-cells = <1>; | ||
80 | compatible = "samsung,s3c24xx-gpio"; | ||
81 | reg = <0x56000000 0x10>; | ||
82 | #gpio-cells = <3>; | ||
83 | gpio-controller; | ||
84 | }; | ||