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Documentation / devicetree / bindings / arm / atmel-adc.txt


Based on kernel version 3.14.11. Page generated on 2014-07-07 08:52 EST.

1	* AT91's Analog to Digital Converter (ADC)
2	
3	Required properties:
4	  - compatible: Should be "atmel,<chip>-adc"
5	    <chip> can be "at91sam9260", "at91sam9g45" or "at91sam9x5"
6	  - reg: Should contain ADC registers location and length
7	  - interrupts: Should contain the IRQ line for the ADC
8	  - atmel,adc-channels-used: Bitmask of the channels muxed and enable for this
9	    device
10	  - atmel,adc-startup-time: Startup Time of the ADC in microseconds as
11	    defined in the datasheet
12	  - atmel,adc-vref: Reference voltage in millivolts for the conversions
13	  - atmel,adc-res: List of resolution in bits supported by the ADC. List size
14			   must be two at least.
15	  - atmel,adc-res-names: Contains one identifier string for each resolution
16				 in atmel,adc-res property. "lowres" and "highres"
17				 identifiers are required.
18	
19	Optional properties:
20	  - atmel,adc-use-external: Boolean to enable of external triggers
21	  - atmel,adc-use-res: String corresponding to an identifier from
22			       atmel,adc-res-names property. If not specified, the highest
23			       resolution will be used.
24	  - atmel,adc-sleep-mode: Boolean to enable sleep mode when no conversion
25	  - atmel,adc-sample-hold-time: Sample and Hold Time in microseconds
26	  - atmel,adc-ts-wires: Number of touch screen wires. Should be 4 or 5. If this
27	                        value is set, then adc driver will enable touch screen
28	                        support.
29	    NOTE: when adc touch screen enabled, the adc hardware trigger will be
30	          disabled. Since touch screen will occupied the trigger register.
31	  - atmel,adc-ts-pressure-threshold: a pressure threshold for touchscreen. It
32	                                     make touch detect more precision.
33	 
34	Optional trigger Nodes:
35	  - Required properties:
36	    * trigger-name: Name of the trigger exposed to the user
37	    * trigger-value: Value to put in the Trigger register
38	      to activate this trigger
39	  - Optional properties:
40	    * trigger-external: Is the trigger an external trigger?
41	
42	Examples:
43	adc0: adc@fffb0000 {
44		compatible = "atmel,at91sam9260-adc";
45		reg = <0xfffb0000 0x100>;
46		interrupts = <20 4>;
47		atmel,adc-channel-base = <0x30>;
48		atmel,adc-channels-used = <0xff>;
49		atmel,adc-drdy-mask = <0x10000>;
50		atmel,adc-num-channels = <8>;
51		atmel,adc-startup-time = <40>;
52		atmel,adc-status-register = <0x1c>;
53		atmel,adc-trigger-register = <0x08>;
54		atmel,adc-use-external;
55		atmel,adc-vref = <3300>;
56		atmel,adc-res = <8 10>;
57		atmel,adc-res-names = "lowres", "highres";
58		atmel,adc-use-res = "lowres";
59	
60		trigger@0 {
61			trigger-name = "external-rising";
62			trigger-value = <0x1>;
63			trigger-external;
64		};
65		trigger@1 {
66			trigger-name = "external-falling";
67			trigger-value = <0x2>;
68			trigger-external;
69		};
70	
71		trigger@2 {
72			trigger-name = "external-any";
73			trigger-value = <0x3>;
74			trigger-external;
75		};
76	
77		trigger@3 {
78			trigger-name = "continuous";
79			trigger-value = <0x6>;
80		};
81	};
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