Kernel-3.10.0-957.el7_atmel-adc

  • AT91’s Analog to Digital Converter (ADC)

Required properties:

  • compatible: Should be “atmel,at91sam9260-adc”
  • reg: Should contain ADC registers location and length
  • interrupts: Should contain the IRQ line for the ADC
  • atmel,adc-channel-base: Offset of the first channel data register
  • atmel,adc-channels-used: Bitmask of the channels muxed and enable for this
    device
  • atmel,adc-drdy-mask: Mask of the DRDY interruption in the ADC
  • atmel,adc-num-channels: Number of channels available in the ADC
  • atmel,adc-startup-time: Startup Time of the ADC in microseconds as
    defined in the datasheet
  • atmel,adc-status-register: Offset of the Interrupt Status Register
  • atmel,adc-trigger-register: Offset of the Trigger Register
  • atmel,adc-vref: Reference voltage in millivolts for the conversions
  • atmel,adc-res: List of resolution in bits supported by the ADC. List size
       must be two at least.
    
  • atmel,adc-res-names: Contains one identifier string for each resolution
         in atmel,adc-res property. "lowres" and "highres"
         identifiers are required.
    

Optional properties:

  • atmel,adc-use-external: Boolean to enable of external triggers

  • atmel,adc-use-res: String corresponding to an identifier from

           atmel,adc-res-names property. If not specified, the highest
           resolution will be used.
    
  • atmel,adc-sleep-mode: Boolean to enable sleep mode when no conversion

  • atmel,adc-sample-hold-time: Sample and Hold Time in microseconds

    Optional trigger Nodes:

  • Required properties:

    • trigger-name: Name of the trigger exposed to the user
    • trigger-value: Value to put in the Trigger register
      to activate this trigger
  • Optional properties:

    • trigger-external: Is the trigger an external trigger?

Examples:
adc0: adc@fffb0000 {
compatible = “atmel,at91sam9260-adc”;
reg = <0xfffb0000 0x100>;
interrupts = <20 4>;
atmel,adc-channel-base = <0x30>;
atmel,adc-channels-used = <0xff>;
atmel,adc-drdy-mask = <0x10000>;
atmel,adc-num-channels = <8>;
atmel,adc-startup-time = <40>;
atmel,adc-status-register = <0x1c>;
atmel,adc-trigger-register = <0x08>;
atmel,adc-use-external;
atmel,adc-vref = <3300>;
atmel,adc-res = <8 10>;
atmel,adc-res-names = “lowres”, “highres”;
atmel,adc-use-res = “lowres”;

trigger@0 {
    trigger-name = "external-rising";
    trigger-value = <0x1>;
    trigger-external;
};
trigger@1 {
    trigger-name = "external-falling";
    trigger-value = <0x2>;
    trigger-external;
};

trigger@2 {
    trigger-name = "external-any";
    trigger-value = <0x3>;
    trigger-external;
};

trigger@3 {
    trigger-name = "continuous";
    trigger-value = <0x6>;
};

};