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 trigger0 { 63 trigger-name = "external-rising"; 64 trigger-value = <0x1>; 65 trigger-external; 66 }; 67 trigger1 { 68 trigger-name = "external-falling"; 69 trigger-value = <0x2>; 70 trigger-external; 71 }; 72 73 trigger2 { 74 trigger-name = "external-any"; 75 trigger-value = <0x3>; 76 trigger-external; 77 }; 78 79 trigger3 { 80 trigger-name = "continuous"; 81 trigger-value = <0x6>; 82 }; 83}; 84