Re: [PATCH 2/2] ASoC: codecs: soundwire: call pm_runtime_resume() in component probe

[Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>]

On 6/17/22 12:37, Mark Brown wrote:
> On Fri, Jun 17, 2022 at 09:35:26AM -0500, Pierre-Louis Bossart wrote:
> 
>> What this patch does it make sure that the bus is operation when the
>> card is created. In usual cases, this is a no-op, this just helps with
>> corner test cases. It's not plugging a major hole in the pm_runtime
>> support, just fixing a programming sequence that was not tested before.
> 
>> One possible objection is that we don't keep the reference and the bus
>> active until all components are probed. I tried doing this at the ASoC
>> core level, but that breaks all kinds of devices that have their own
>> quirky way of dealing with pm_runtime - specifically HDaudio and HDMI.
>> That's why I added this resume here.
> 
>> Makes sense?
> 
> Ish.  Ugh, right.  So it's not fixing anything really, it's mainly
> papering over cracks where things are being missed.  In any case it's
> not doing any harm and it helps things for now.

You got it right. There are additional patches that were sent to use
pm_runtime_resume_and_get() on set_jack, and other clear cases that were
missed, but this is more of a blanket "do not harm" resume in case codec
drivers are missing something.