[alsa-devel] [PATCH] ASoC: rsnd: stop all working stream when .remove

[Takashi Iwai]

On Fri, 01 Sep 2017 06:34:48 +0200,
Kuninori Morimoto wrote:
> 
> 
> From: Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>
> 
> Driver should stop all working stream when .remove timing.
> Current Renesas sound driver is assuming that all stream was
> stopped when .remove but it was wrong.
> This patch stops all working stream when .remove, otherwise
> kernel will get damage for example in below case.
> Special thanks to Truong, Hiep
> 
> 	> cd /sys/bus/platform/drivers/rcar_sound
> 	> aplay xxx.wav &
> 	> echo ec500000.sound > unbind
> 
> Reported-by: Hiep Cao Minh <cm-hiep at jinso.co.jp>
> Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>

The lack of stop sync is a known problem in the ALSA PCM
infrastructure.  The standard idiom is to do sync at both prepare and
hw_free (or close) callbacks.


Takashi