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

From: Srinivas Kandagatla
Date: Thu Apr 01 2021 - 14:07:01 EST




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