1*4882a593SmuzhiyunNuvoton NAU8824 audio codec 2*4882a593Smuzhiyun 3*4882a593SmuzhiyunThis device supports I2C only. 4*4882a593Smuzhiyun 5*4882a593SmuzhiyunRequired properties: 6*4882a593Smuzhiyun - compatible : Must be "nuvoton,nau8824" 7*4882a593Smuzhiyun 8*4882a593Smuzhiyun - reg : the I2C address of the device. This is either 0x1a (CSB=0) or 0x1b (CSB=1). 9*4882a593Smuzhiyun 10*4882a593SmuzhiyunOptional properties: 11*4882a593Smuzhiyun - nuvoton,jkdet-polarity: JKDET pin polarity. 0 - active high, 1 - active low. 12*4882a593Smuzhiyun 13*4882a593Smuzhiyun - nuvoton,vref-impedance: VREF Impedance selection 14*4882a593Smuzhiyun 0 - Open 15*4882a593Smuzhiyun 1 - 25 kOhm 16*4882a593Smuzhiyun 2 - 125 kOhm 17*4882a593Smuzhiyun 3 - 2.5 kOhm 18*4882a593Smuzhiyun 19*4882a593Smuzhiyun - nuvoton,micbias-voltage: Micbias voltage level. 20*4882a593Smuzhiyun 0 - VDDA 21*4882a593Smuzhiyun 1 - VDDA 22*4882a593Smuzhiyun 2 - VDDA * 1.1 23*4882a593Smuzhiyun 3 - VDDA * 1.2 24*4882a593Smuzhiyun 4 - VDDA * 1.3 25*4882a593Smuzhiyun 5 - VDDA * 1.4 26*4882a593Smuzhiyun 6 - VDDA * 1.53 27*4882a593Smuzhiyun 7 - VDDA * 1.53 28*4882a593Smuzhiyun 29*4882a593Smuzhiyun - nuvoton,sar-threshold-num: Number of buttons supported 30*4882a593Smuzhiyun - nuvoton,sar-threshold: Impedance threshold for each button. Array that contains up to 8 buttons configuration. SAR value is calculated as 31*4882a593Smuzhiyun SAR = 255 * MICBIAS / SAR_VOLTAGE * R / (2000 + R) 32*4882a593Smuzhiyun where MICBIAS is configured by 'nuvoton,micbias-voltage', SAR_VOLTAGE is configured by 'nuvoton,sar-voltage', R - button impedance. 33*4882a593Smuzhiyun Refer datasheet section 10.2 for more information about threshold calculation. 34*4882a593Smuzhiyun 35*4882a593Smuzhiyun - nuvoton,sar-hysteresis: Button impedance measurement hysteresis. 36*4882a593Smuzhiyun 37*4882a593Smuzhiyun - nuvoton,sar-voltage: Reference voltage for button impedance measurement. 38*4882a593Smuzhiyun 0 - VDDA 39*4882a593Smuzhiyun 1 - VDDA 40*4882a593Smuzhiyun 2 - VDDA * 1.1 41*4882a593Smuzhiyun 3 - VDDA * 1.2 42*4882a593Smuzhiyun 4 - VDDA * 1.3 43*4882a593Smuzhiyun 5 - VDDA * 1.4 44*4882a593Smuzhiyun 6 - VDDA * 1.53 45*4882a593Smuzhiyun 7 - VDDA * 1.53 46*4882a593Smuzhiyun 47*4882a593Smuzhiyun - nuvoton,sar-compare-time: SAR compare time 48*4882a593Smuzhiyun 0 - 500 ns 49*4882a593Smuzhiyun 1 - 1 us 50*4882a593Smuzhiyun 2 - 2 us 51*4882a593Smuzhiyun 3 - 4 us 52*4882a593Smuzhiyun 53*4882a593Smuzhiyun - nuvoton,sar-sampling-time: SAR sampling time 54*4882a593Smuzhiyun 0 - 2 us 55*4882a593Smuzhiyun 1 - 4 us 56*4882a593Smuzhiyun 2 - 8 us 57*4882a593Smuzhiyun 3 - 16 us 58*4882a593Smuzhiyun 59*4882a593Smuzhiyun - nuvoton,short-key-debounce: Button short key press debounce time. 60*4882a593Smuzhiyun 0 - 30 ms 61*4882a593Smuzhiyun 1 - 50 ms 62*4882a593Smuzhiyun 2 - 100 ms 63*4882a593Smuzhiyun 64*4882a593Smuzhiyun - nuvoton,jack-eject-debounce: Jack ejection debounce time. 65*4882a593Smuzhiyun 0 - 0 ms 66*4882a593Smuzhiyun 1 - 1 ms 67*4882a593Smuzhiyun 2 - 10 ms 68*4882a593Smuzhiyun 69*4882a593Smuzhiyun 70*4882a593SmuzhiyunExample: 71*4882a593Smuzhiyun 72*4882a593Smuzhiyun headset: nau8824@1a { 73*4882a593Smuzhiyun compatible = "nuvoton,nau8824"; 74*4882a593Smuzhiyun reg = <0x1a>; 75*4882a593Smuzhiyun interrupt-parent = <&gpio>; 76*4882a593Smuzhiyun interrupts = <TEGRA_GPIO(E, 6) IRQ_TYPE_LEVEL_LOW>; 77*4882a593Smuzhiyun nuvoton,vref-impedance = <2>; 78*4882a593Smuzhiyun nuvoton,micbias-voltage = <6>; 79*4882a593Smuzhiyun // Setup 4 buttons impedance according to Android specification 80*4882a593Smuzhiyun nuvoton,sar-threshold-num = <4>; 81*4882a593Smuzhiyun nuvoton,sar-threshold = <0xc 0x1e 0x38 0x60>; 82*4882a593Smuzhiyun nuvoton,sar-hysteresis = <0>; 83*4882a593Smuzhiyun nuvoton,sar-voltage = <6>; 84*4882a593Smuzhiyun nuvoton,sar-compare-time = <1>; 85*4882a593Smuzhiyun nuvoton,sar-sampling-time = <1>; 86*4882a593Smuzhiyun nuvoton,short-key-debounce = <0>; 87*4882a593Smuzhiyun nuvoton,jack-eject-debounce = <1>; 88*4882a593Smuzhiyun }; 89