Documentation/devicetree/bindings/sound/nau8825.txt

   1 Nuvoton NAU8825 audio codec
   2
   3 This device supports I2C only.
   4
   5 Required properties:
   6   - compatible : Must be "nuvoton,nau8825"
   7
   8   - reg : the I2C address of the device. This is either 0x1a (CSB=0) or 0x1b (CSB=1).
   9
  10 Optional properties:
  11   - nuvoton,jkdet-enable: Enable jack detection via JKDET pin.
  12   - nuvoton,jkdet-pull-enable: Enable JKDET pin pull. If set - pin pull enabled,
  13       otherwise pin in high impedance state.
  14   - nuvoton,jkdet-pull-up: Pull-up JKDET pin. If set then JKDET pin is pull up, otherwise pull down.
  15   - nuvoton,jkdet-polarity: JKDET pin polarity. 0 - active high, 1 - active low.
  16
  17   - nuvoton,vref-impedance: VREF Impedance selection
  18       0 - Open
  19       1 - 25 kOhm
  20       2 - 125 kOhm
  21       3 - 2.5 kOhm
  22
  23   - nuvoton,micbias-voltage: Micbias voltage level.
  24       0 - VDDA
  25       1 - VDDA
  26       2 - VDDA * 1.1
  27       3 - VDDA * 1.2
  28       4 - VDDA * 1.3
  29       5 - VDDA * 1.4
  30       6 - VDDA * 1.53
  31       7 - VDDA * 1.53
  32
  33   - nuvoton,sar-threshold-num: Number of buttons supported
  34   - nuvoton,sar-threshold: Impedance threshold for each button. Array that contains up to 8 buttons configuration. SAR value is calculated as
  35     SAR = 255 * MICBIAS / SAR_VOLTAGE * R / (2000 + R)
  36     where MICBIAS is configured by 'nuvoton,micbias-voltage', SAR_VOLTAGE is configured by 'nuvoton,sar-voltage', R - button impedance.
  37     Refer datasheet section 10.2 for more information about threshold calculation.
  38
  39   - nuvoton,sar-hysteresis: Button impedance measurement hysteresis.
  40
  41   - nuvoton,sar-voltage: Reference voltage for button impedance measurement.
  42       0 - VDDA
  43       1 - VDDA
  44       2 - VDDA * 1.1
  45       3 - VDDA * 1.2
  46       4 - VDDA * 1.3
  47       5 - VDDA * 1.4
  48       6 - VDDA * 1.53
  49       7 - VDDA * 1.53
  50
  51   - nuvoton,sar-compare-time: SAR compare time
  52       0 - 500 ns
  53       1 - 1 us
  54       2 - 2 us
  55       3 - 4 us
  56
  57   - nuvoton,sar-sampling-time: SAR sampling time
  58       0 - 2 us
  59       1 - 4 us
  60       2 - 8 us
  61       3 - 16 us
  62
  63   - nuvoton,short-key-debounce: Button short key press debounce time.
  64       0 - 30 ms
  65       1 - 50 ms
  66       2 - 100 ms
  67       3 - 30 ms
  68
  69   - nuvoton,jack-insert-debounce: number from 0 to 7 that sets debounce time to 2^(n+2) ms
  70   - nuvoton,jack-eject-debounce: number from 0 to 7 that sets debounce time to 2^(n+2) ms
  71
  72   - clocks: list of phandle and clock specifier pairs according to common clock bindings for the
  73       clocks described in clock-names
  74   - clock-names: should include "mclk" for the MCLK master clock
  75
  76 Example:
  77
  78   headset: nau8825@1a {
  79       compatible = "nuvoton,nau8825";
  80       reg = <0x1a>;
  81       interrupt-parent = <&gpio>;
  82       interrupts = <TEGRA_GPIO(E, 6) IRQ_TYPE_LEVEL_LOW>;
  83       nuvoton,jkdet-enable;
  84       nuvoton,jkdet-pull-enable;
  85       nuvoton,jkdet-pull-up;
  86       nuvoton,jkdet-polarity = <GPIO_ACTIVE_LOW>;
  87       nuvoton,vref-impedance = <2>;
  88       nuvoton,micbias-voltage = <6>;
  89       // Setup 4 buttons impedance according to Android specification
  90       nuvoton,sar-threshold-num = <4>;
  91       nuvoton,sar-threshold = <0xc 0x1e 0x38 0x60>;
  92       nuvoton,sar-hysteresis = <1>;
  93       nuvoton,sar-voltage = <0>;
  94       nuvoton,sar-compare-time = <0>;
  95       nuvoton,sar-sampling-time = <0>;
  96       nuvoton,short-key-debounce = <2>;
  97       nuvoton,jack-insert-debounce = <7>;
  98       nuvoton,jack-eject-debounce = <7>;
  99
 100       clock-names = "mclk";
 101       clocks = <&tegra_car TEGRA210_CLK_CLK_OUT_2>;
 102   };