[alsa-devel] regression introduced by commit 70d435ba1cd6 ("ASoC: imx-pcm-dma: simplify pcm_config")

[Lothar Waßmann]

Hi,

On Tue, 10 Oct 2017 16:49:04 +0200 Lucas Stach wrote:
> Hi Lothar,
> 
> Am Mittwoch, den 04.10.2017, 10:36 +0200 schrieb Lothar Waßmann:
> > Hi,
> > 
> > the commit 70d435ba1cd6 ("ASoC: imx-pcm-dma: simplify pcm_config")
> > introduced a regression on the Ka-Ro TX series modules (and possibly
> > other hardware as well).
> > 
> > The problem is, that this commit restricts the supported sound
> > formats
> > to S24_LE only rather than S16_LE, S24_LE, S20_3LE without the
> > patch. Therefore aplay fails with the following error messages, when
> > trying to play a sound file with S16_LE format:
> > > ALSA lib alsa-lib-
> > > 1.1.2/src/pcm/pcm_params.c:2162:(snd1_pcm_hw_refine_slave) Slave
> > > PCM not usable
> > > aplay: set_params:1204: Broken configuration for this PCM: no
> > > configurations available
> > 
> > This is with the simple-sound-card driver as well as the imx-sgtl5000
> > driver.
> > 
> > Can someone tell me on what hardware and with what software has this
> > patch been tested?
> 
> My primary test hardware was the zii-rdu2 board, the DTS for this board
> can be found in recent mainline kernels.
> 
> Userspace is based on pulseaudio, which may mask the regression by
> resampling to the supported format. Sorry about that.
> 
> From my understanding of the code, it should be possible to fix the
> regression without reverting this patch by setting
> SND_DMAENGINE_PCM_DAI_FLAG_PACK in the flags field of the DMA params in
> fsl_ssi.
> 
I tried that, but then I get DMA timeouts.

I circumvented the problem by changing my /etc/asound.conf to use the
only supported sample format. So, if nobody else has a problem, there
is no need to revert the patch or apply additional modifications to the
driver.


Lothar Waßmann