[PATCH v2] soundwire: qcom: wait for fifo space to be available before read/write

[Srinivas Kandagatla]

On 01/04/2021 15:36, Pierre-Louis Bossart wrote:
> 
> 
> On 4/1/21 4:00 AM, Srinivas Kandagatla wrote:
>> If we write registers very fast we can endup in a situation where some
>> of the writes will be dropped without any notice.
>>
>> So wait for the fifo space to be available before reading/writing the
>> soundwire registers.
> 
> Out of curiosity, do you actually need to do a check in the read case as 
> well?

Yes, This is just to make sure the read command is finished and fifo is 
ready with data.

If not we will be reading quickly an empty fifo!

> 
> The commit message talks about writes getting dropped, is the opposite 
> also a problem?

Its highly likely, for safety I have added support for both write and 
read waits in this patch.


--srini
>