On Fri, Sep 15, 2017 at 02:20:09AM +0000, Oder Chiou wrote:

Sorry for my poor explanation.

That's OK.

The impedance table should like the following setting in the DTS. < 0 300 7 0xffd160 0xffd1c0 0xff8a10 0xff8ab0 301 65535 4 0xffe470 0xffe470 0xffb8e0 0xffb8e0> The first and second column are defined for the impedance range. If the detected impedance value is in the range, then the volume value of the third column will be set to codec. In our codec design, each volume value should compensate different DC offset to avoid the pop sound, and it is also different between headphone and headset. In the example, the "realtek,impedance_sensing_num" is 2. It means that there are 2 ranges of impedance in the impedance sensing function, and it also can be defined the device whether can support this function or not.

This stuff looks fairly good, can you put it in the binding document please?