ASoC: soc-pcm: Don't zero TDM masks in __soc_pcm_open() breaks SOF Audio in Lenovo laptops

[Richard Fitzgerald]

On 9/12/22 16:18, Mark Brown wrote:
> On Fri, Dec 09, 2022 at 05:38:54PM +0200, Péter Ujfalusi wrote:
>> On 09/12/2022 16:42, Pierre-Louis Bossart wrote:
> 
>>> Agree with the analysis, so what would be the least bad recommendation?
>>> a) revert the "don't zero TDM masks" patch
>>> b) backport the change to use set_stream()?
> 
>> I would vote for b) unless other platforms report regressions.
> 
> I don't really care either way given the backport policy.

Neither do I.
If you want to minimize risk, revert the patch in older backports.

Lessons learned:
Don't hijack a data member to pass something different from what it
is intended to hold.
Don't depend on a bug.
Don't assume all code is using a data member for what is supposed to be
in that member.