[PATCH] ALSA: hda/hdmi: fix race in monitor detection during probe

[Takashi Iwai]

On Tue, 28 Apr 2020 14:38:36 +0200,
Kai Vehmanen wrote:
> 
> A race exists between build_pcms() and build_controls() phases of codec
> setup. Build_pcms() sets up notifier for jack events. If a monitor event
> is received before build_controls() is run, the initial jack state is
> lost and never reported via mixer controls.
> 
> The problem can be hit at least with SOF as the controller driver. SOF
> calls snd_hda_codec_build_controls() in its workqueue-based probe and
> this can be delayed enough to hit the race condition.
> 
> Fix the issue by invalidating the per-pin ELD information when
> build_controls() is called. The existing call to hdmi_present_sense()
> will update the ELD contents. This ensures initial monitor state is
> correctly reflected via mixer controls.
> 
> BugLink: https://github.com/thesofproject/linux/issues/1687
> Signed-off-by: Kai Vehmanen <kai.vehmanen at linux.intel.com>

Applied, thanks.


Takashi