[alsa-devel] [PATCH] ASoC: fsl_ssi: Add suspend/resume support

[Shawn Guo]

On Fri, May 23, 2014 at 02:38:56AM -0300, Fabio Estevam wrote:
> From: Fabio Estevam <fabio.estevam at freescale.com>
> 
> Doing a suspend/resume sequence while playing an audio track in the backgroung
> causes broken audio right after resume:
> 
> root at freescale /$ aplay clarinet.wav &
> 
> root at freescale /home$ Playing WAVE 'clarinet.wav' : Signed 16 bit Little Endian,
>  Rate 44100 Hz, Mono
> 
> root at freescale /home$ echo mem > /sys/power/state 
> PM: Syncing filesystems ... done.
> Freezing user space processes ... (elapsed 0.002 seconds) done.
> Freezing remaining freezable tasks ... (elapsed 0.002 seconds) done.
> Suspending console(s) (use no_console_suspend to debug)
> PM: suspend of devices complete after 37.082 msecs
> PM: suspend devices took 0.040 seconds
> PM: late suspend of devices complete after 4.234 msecs
> PM: noirq suspend of devices complete after 4.618 msecs
> Disabling non-boot CPUs ...
> PM: noirq resume of devices complete after 4.013 msecs
> PM: early resume of devices complete after 4.000 msecs
> PM: resume of devices complete after 68.907 msecs
> PM: resume devices took 0.070 seconds
> Restarting tasks ... Suspended. Trying resume. Failed. Restarting stream. Done.
> Suspended. Trying resume. Failed. Restarting stream. Done.
> Suspended. Trying resume. Failed. Restarting stream. Done.
> Suspended. Trying resume. Failed. Restarting stream. Done.
> Suspended. Trying resume. Failed. Restarting stream. Done.
> Suspended. Trying resume. Failed. Restarting stream. Done.
> Suspended. Trying resume. Failed. Restarting stream. Done.
> ....
> 
> Add SNDRV_PCM_TRIGGER_RESUME/SUSPEND cases so that we can gracefully handle
> system suspend/resume.
> 
> Signed-off-by: Fabio Estevam <fabio.estevam at freescale.com>

Acked-by: Shawn Guo <shawn.guo at freescale.com>