[PATCH V3 4/4] ASoC: fsl_asrc: Fix error with S24_3LE format bitstream in i.MX8

[S.j. Wang]

Hi
> 
> One issue for error-out and some nit-pickings inline. Thanks.
> 
> On Thu, Sep 19, 2019 at 08:11:42PM +0800, Shengjiu Wang wrote:
> > There is error "aplay: pcm_write:2023: write error: Input/output error"
> > on i.MX8QM/i.MX8QXP platform for S24_3LE format.
> >
> > In i.MX8QM/i.MX8QXP, the DMA is EDMA, which don't support 24bit
> > sample, but we didn't add any constraint, that cause issues.
> >
> > So we need to query the caps of dma, then update the hw parameters
> > according to the caps.
> >
> > Signed-off-by: Shengjiu Wang <shengjiu.wang at nxp.com>
> > ---
> >  sound/soc/fsl/fsl_asrc.c     |  4 +--
> >  sound/soc/fsl/fsl_asrc.h     |  3 +++
> >  sound/soc/fsl/fsl_asrc_dma.c | 52
> > +++++++++++++++++++++++++++++++-----
> >  3 files changed, 50 insertions(+), 9 deletions(-)
> >
> > @@ -276,6 +274,11 @@ static int fsl_asrc_dma_startup(struct
> snd_pcm_substream *substream)
> >       struct device *dev = component->dev;
> >       struct fsl_asrc *asrc_priv = dev_get_drvdata(dev);
> >       struct fsl_asrc_pair *pair;
> > +     bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
> > +     u8 dir = tx ? OUT : IN;
> > +     struct dma_chan *tmp_chan;
> > +     struct snd_dmaengine_dai_dma_data *dma_data;
> 
> Nit: would it be possible to reorganize these a bit? Usually we put struct
> things together unless there is a dependency, similar to
> fsl_asrc_dma_hw_params().
> 
> > @@ -285,9 +288,44 @@ static int fsl_asrc_dma_startup(struct
> > snd_pcm_substream *substream)
> >
> >       runtime->private_data = pair;
> >
> > +     /* Request a temp pair, which is release in the end */
> 
> Nit: "which will be released later" or "and will release it later"? And could
> we use a work like "dummy"? Or at least I would love to see the comments
> explaining the parameter "1"
> in the function call below.
> 
> > +     ret = fsl_asrc_request_pair(1, pair);
> > +     if (ret < 0) {
> > +             dev_err(dev, "failed to request asrc pair\n");
> > +             return ret;
> > +     }
> > +
> > +     tmp_chan = fsl_asrc_get_dma_channel(pair, dir);
> > +     if (!tmp_chan) {
> > +             dev_err(dev, "can't get dma channel\n");
> 
> Could we align with other error messages using "failed to"?
> 
> > +     ret = snd_soc_set_runtime_hwparams(substream,
> &snd_imx_hardware);
> > +     if (ret)
> > +             return ret;
> > +
> [...]
> > +     dma_release_channel(tmp_chan);
> > +     fsl_asrc_release_pair(pair);
> 
> I think we need an "out:" here for those error-out routines to goto.
> Otherwise, it'd be a pair leak?
> 
> > +
> 
> Could we drop this? There is a blank line below already :)
> 

Will update them.

Best regards
Wang Shengjiu