On Tue, Jun 16, 2020 at 10:54:17AM +0200, Stephan Gerhold wrote: > Hi Pierre, > > On Mon, Jun 08, 2020 at 02:44:12PM -0500, Pierre-Louis Bossart wrote: > > Recent changes in the ASoC core prevent multi-cpu BE dailinks from > > being used. DPCM does support multi-cpu DAIs for BE Dailinks, but not > > for FE. > > First I want to apologize for introducing this regression. > Actually when I made the "Only allow playback/capture if supported" > patch I did not realize it would also be used for BE DAIs. :) > > > > > Handle the FE checks first, and make sure all DAIs support the same > > capabilities within the same dailink. > > > > BugLink: https://github.com/thesofproject/linux/issues/2031 > > Fixes: 9b5db059366ae2 ("ASoC: soc-pcm: dpcm: Only allow playback/capture if supported") > > Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx> > > Reviewed-by: Bard Liao <yung-chuan.liao@xxxxxxxxxxxxxxx> > > Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@xxxxxxxxxxxxxxx> > > Reviewed-by: Ranjani Sridharan <ranjani.sridharan@xxxxxxxxxxxxxxx> > > Reviewed-by: Daniel Baluta <daniel.baluta@xxxxxxxxx> > > --- > > sound/soc/soc-pcm.c | 44 ++++++++++++++++++++++++++++++++++---------- > > 1 file changed, 34 insertions(+), 10 deletions(-) > > > > diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c > > index 276505fb9d50..2c114b4542ce 100644 > > --- a/sound/soc/soc-pcm.c > > +++ b/sound/soc/soc-pcm.c > > @@ -2789,20 +2789,44 @@ int soc_new_pcm(struct snd_soc_pcm_runtime *rtd, int num) > > struct snd_pcm *pcm; > > char new_name[64]; > > int ret = 0, playback = 0, capture = 0; > > + int stream; > > int i; > > > > + if (rtd->dai_link->dynamic && rtd->num_cpus > 1) { > > + dev_err(rtd->dev, > > + "DPCM doesn't support Multi CPU for Front-Ends yet\n"); > > + return -EINVAL; > > + } > > + > > if (rtd->dai_link->dynamic || rtd->dai_link->no_pcm) { > > - cpu_dai = asoc_rtd_to_cpu(rtd, 0); > > - if (rtd->num_cpus > 1) { > > - dev_err(rtd->dev, > > - "DPCM doesn't support Multi CPU yet\n"); > > - return -EINVAL; > > + if (rtd->dai_link->dpcm_playback) { > > + stream = SNDRV_PCM_STREAM_PLAYBACK; > > + > > + for_each_rtd_cpu_dais(rtd, i, cpu_dai) > > + if (!snd_soc_dai_stream_valid(cpu_dai, > > + stream)) { > > + dev_err(rtd->card->dev, > > + "CPU DAI %s for rtd %s does not support playback\n", > > + cpu_dai->name, > > + rtd->dai_link->stream_name); > > + return -EINVAL; > > Unfortunately the "return -EINVAL" here and below break the case where > dpcm_playback/dpcm_capture does not exactly match the capabilities of > the referenced CPU DAIs. To quote from my commit message: > > At the moment, PCM devices for DPCM are only created based on the > dpcm_playback/capture parameters of the DAI link, without considering > if the CPU/FE DAI is actually capable of playback/capture. > > Normally the dpcm_playback/capture parameter should match the > capabilities of the CPU DAI. However, there is no way to set that > parameter from the device tree (e.g. with simple-audio-card or > qcom sound cards). dpcm_playback/capture are always both set to 1. > > The basic idea for my commit was to basically stop using > dpcm_playback/capture for the device tree case and infer the > capabilities solely based on referenced DAIs. The DAIs expose if they > are capable of playback/capture, so I see no reason to be required to > duplicate that into the DAI link setup (unless you want to specifically > restrict a DAI link to one direction for some reason...) > > With your patch probe now fails with: > > 7702000.sound: CPU DAI MultiMedia1 for rtd MultiMedia1 does not support capture > > because sound/soc/qcom/common.c sets dpcm_playback = dpcm_capture = 1 > even though that FE DAI is currently configured to be playback-only. > > I believe Srinivas fixed that problem for the BE DAIs in > commit a2120089251f ("ASoC: qcom: common: set correct directions for dailinks") > (https://lore.kernel.org/alsa-devel/20200612123711.29130-2-srinivas.kandagatla@xxxxxxxxxx/) > > For the QCOM case it may be feasible to set dpcm_playback/dpcm_capture > appropriately because it is basically only used with one particular > DAI driver. But simple-audio-card is generic and used with many > different drivers so hard-coding a call into some other driver like > Srinivas did above won't work in that case. > > I wonder if we should downgrade your dev_err(...) to a dev_dbg(...), > and then simply avoid setting playback/capture = 0. Hmm, I wanted to write "avoid setting playback/capture = 1" here of course. If dpcm_playback/capture is set but not actually supported don't error out but just ignore it. That would essentially make dpcm_playback/capture just a restriction of the CPU DAI capabilities. Not sure if there is even a usecase for such a restriction, maybe dpcm_playback/capture could even be removed entirely... > This should fix the case I'm talking about. > > What do you think? > > Thanks, > Stephan > > > + } > > + playback = 1; > > + } > > + if (rtd->dai_link->dpcm_capture) { > > + stream = SNDRV_PCM_STREAM_CAPTURE; > > + > > + for_each_rtd_cpu_dais(rtd, i, cpu_dai) > > + if (!snd_soc_dai_stream_valid(cpu_dai, > > + stream)) { > > + dev_err(rtd->card->dev, > > + "CPU DAI %s for rtd %s does not support capture\n", > > + cpu_dai->name, > > + rtd->dai_link->stream_name); > > + return -EINVAL; > > + } > > + capture = 1; > > } > > - > > - playback = rtd->dai_link->dpcm_playback && > > - snd_soc_dai_stream_valid(cpu_dai, SNDRV_PCM_STREAM_PLAYBACK); > > - capture = rtd->dai_link->dpcm_capture && > > - snd_soc_dai_stream_valid(cpu_dai, SNDRV_PCM_STREAM_CAPTURE); > > } else { > > /* Adapt stream for codec2codec links */ > > int cpu_capture = rtd->dai_link->params ? > > -- > > 2.20.1 > >
