Re: [PATCH 8/9] ASoC: Intel: bytcr_rt5640: Drop unwanted ignore_suspend settings

From: Hans de Goede
Date: Sun Mar 04 2018 - 09:11:21 EST


Hi,

On 01-03-18 18:17, Mark Brown wrote:
On Thu, Mar 01, 2018 at 05:58:35PM +0100, Hans de Goede wrote:
On 01-03-18 17:48, Mark Brown wrote:

That sounds like what's missing is hookup of whatever the DSP uses to
wake the system when it's getting to the bottom of the buffer? That's
the normal way this stuff is implemented anyway.

I'm afraid there is a lot more missing, at least from a standard Linux
distro pov, just waking up is not enough, we need to also wakeup
userspace to get the mp3-player (or whatever) to refill the buffer,
but preferably without waking up the GPU, turning on the screen, etc.

AFAIK support for this is currently completely missing, standard Linux
userspace currently treats suspend-2-idle as a a full suspend and any
wakeup as a full wakeup.

Sure, but do such userspaces exist - ChromeOS or something for example?

ChromeOS has a more or less standard userspace I believe.

So AFAICT currently the ignore-suspend flag is currently not useful
and as the commit message mentions IIRC there were added to fix some
issues with suspend/resume in the past.

Is it possible the issue was playback during suspend?

There was an issue with suspend being blocked (so the machine not suspending)
if audio was playing because of one the suspend callbacks returning
an error. I believe the ignore_suspend settings where added as a workaround
for that and that is no longer a problem.

Pierre-Louis, do you have any input on this / on this patch?

Regards,

Hans