[alsa-devel] [PATCH] ASoC: nau8810: Add driver for Nuvoton codec chip NAU88C10

[John Hsu]

Hi

On 8/5/2016 8:08 PM, Mark Brown wrote:
> On Mon, Jul 04, 2016 at 11:34:19AM +0800, John Hsu wrote:
>   
>> On 7/1/2016 6:04 PM, Mark Brown wrote:
>>     
>
>   
>>> No, you don't - this is entirely normal for 7x9 regmaps, I've never seen
>>> such a device that supported readback.  Look at devices like wm8731 for
>>> examples.
>>>       
>
>   
>> Sometimes, we need to know the codec information and need read it
>> from hardware, not cache. I'm afraid that it can't be done in this
>> case.
>>     
>
> What does the read actually look like on this device?
>   

The data read from codec by the IIC bus is as the following.
0 0 0 0 0 0 0 D8 ACK D7 D6 D5 D4 D3 D2 D1 D0
The bottom 9 bits are the real register value. The nau8810_reg_read
in driver is made by the formate.