1* AT91's Analog to Digital Converter (ADC)
2
3Required 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  - clock-names: tuple listing input clock names.
9	Required elements: "adc_clk", "adc_op_clk".
10  - clocks: phandles to input clocks.
11  - atmel,adc-channels-used: Bitmask of the channels muxed and enabled for this
12    device
13  - atmel,adc-startup-time: Startup Time of the ADC in microseconds as
14    defined in the datasheet
15  - atmel,adc-vref: Reference voltage in millivolts for the conversions
16  - atmel,adc-res: List of resolutions in bits supported by the ADC. List size
17		   must be two at least.
18  - atmel,adc-res-names: Contains one identifier string for each resolution
19			 in atmel,adc-res property. "lowres" and "highres"
20			 identifiers are required.
21
22Optional properties:
23  - atmel,adc-use-external-triggers: Boolean to enable the external triggers
24  - atmel,adc-use-res: String corresponding to an identifier from
25		       atmel,adc-res-names property. If not specified, the highest
26		       resolution will be used.
27  - atmel,adc-sleep-mode: Boolean to enable sleep mode when no conversion
28  - atmel,adc-sample-hold-time: Sample and Hold Time in microseconds
29  - atmel,adc-ts-wires: Number of touchscreen wires. Should be 4 or 5. If this
30                        value is set, then the adc driver will enable touchscreen
31                        support.
32    NOTE: when adc touchscreen is enabled, the adc hardware trigger will be
33          disabled. Since touchscreen will occupy the trigger register.
34  - atmel,adc-ts-pressure-threshold: a pressure threshold for touchscreen. It
35                                     makes touch detection more precise.
36
37Optional trigger Nodes:
38  - Required properties:
39    * trigger-name: Name of the trigger exposed to the user
40    * trigger-value: Value to put in the Trigger register
41      to activate this trigger
42  - Optional properties:
43    * trigger-external: Is the trigger an external trigger?
44
45Examples:
46adc0: adc@fffb0000 {
47	#address-cells = <1>;
48	#size-cells = <0>;
49	compatible = "atmel,at91sam9260-adc";
50	reg = <0xfffb0000 0x100>;
51	interrupts = <20 IRQ_TYPE_LEVEL_HIGH 0>;
52	clocks = <&adc_clk>, <&adc_op_clk>;
53	clock-names = "adc_clk", "adc_op_clk";
54	atmel,adc-channels-used = <0xff>;
55	atmel,adc-startup-time = <40>;
56	atmel,adc-use-external-triggers;
57	atmel,adc-vref = <3300>;
58	atmel,adc-res = <8 10>;
59	atmel,adc-res-names = "lowres", "highres";
60	atmel,adc-use-res = "lowres";
61
62	trigger@0 {
63		reg = <0>;
64		trigger-name = "external-rising";
65		trigger-value = <0x1>;
66		trigger-external;
67	};
68	trigger@1 {
69		reg = <1>;
70		trigger-name = "external-falling";
71		trigger-value = <0x2>;
72		trigger-external;
73	};
74
75	trigger@2 {
76		reg = <2>;
77		trigger-name = "external-any";
78		trigger-value = <0x3>;
79		trigger-external;
80	};
81
82	trigger@3 {
83		reg = <3>;
84		trigger-name = "continuous";
85		trigger-value = <0x6>;
86	};
87};
88