On Thu, Oct 08, 2020 at 05:11:05PM +0100, Mark Brown wrote: > We intentionally do not return an error if we get a permanent failure > from dma_request_chan() in order to support systems which have TX only > or RX only channels. Add a comment documenting this. Thanks, makes sense! Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxx> > Reported-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxx> > Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> > --- > sound/soc/soc-generic-dmaengine-pcm.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/sound/soc/soc-generic-dmaengine-pcm.c b/sound/soc/soc-generic-dmaengine-pcm.c > index fb95c1464e66..9ef80a48707e 100644 > --- a/sound/soc/soc-generic-dmaengine-pcm.c > +++ b/sound/soc/soc-generic-dmaengine-pcm.c > @@ -386,6 +386,11 @@ static int dmaengine_pcm_request_chan_of(struct dmaengine_pcm *pcm, > name = config->chan_names[i]; > chan = dma_request_chan(dev, name); > if (IS_ERR(chan)) { > + /* > + * Only report probe deferral errors, channels > + * might not be present for devices that > + * support only TX or only RX. > + */ > if (PTR_ERR(chan) == -EPROBE_DEFER) > return -EPROBE_DEFER; > pcm->chan[i] = NULL; > -- > 2.20.1 > -- With Best Regards, Andy Shevchenko