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Documentation / devicetree / bindings / gpio / gpio-samsung.txt




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Based on kernel version 3.9. Page generated on 2013-05-02 22:58 EST.

1	Samsung Exynos4 GPIO Controller
2	
3	Required properties:
4	- compatible: Compatible property value should be "samsung,exynos4-gpio>".
5	
6	- reg: Physical base address of the controller and length of memory mapped
7	  region.
8	
9	- #gpio-cells: Should be 4. The syntax of the gpio specifier used by client nodes
10	  should be the following with values derived from the SoC user manual.
11	     <[phandle of the gpio controller node]
12	      [pin number within the gpio controller]
13	      [mux function]
14	      [flags and pull up/down]
15	      [drive strength]>
16	
17	  Values for gpio specifier:
18	  - Pin number: is a value between 0 to 7.
19	  - Flags and Pull Up/Down: 0 - Pull Up/Down Disabled.
20	                            1 - Pull Down Enabled.
21	                            3 - Pull Up Enabled.
22	          Bit 16 (0x00010000) - Input is active low.
23	  - Drive Strength: 0 - 1x,
24	                    1 - 3x,
25	                    2 - 2x,
26	                    3 - 4x
27	
28	- gpio-controller: Specifies that the node is a gpio controller.
29	- #address-cells: should be 1.
30	- #size-cells: should be 1.
31	
32	Example:
33	
34		gpa0: gpio-controller@11400000 {
35			#address-cells = <1>;
36			#size-cells = <1>;
37			compatible = "samsung,exynos4-gpio";
38			reg = <0x11400000 0x20>;
39			#gpio-cells = <4>;
40			gpio-controller;
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		};
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