Re: [PATCH V6 4/4] ASoC: fsl_asrc: Fix error with S24_3LE format bitstream in i.MX8

[Nicolin Chen]

On Fri, Sep 27, 2019 at 09:46:12AM +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@xxxxxxx>

Acked-by: Nicolin Chen <nicoleotsuka@xxxxxxxxx>

> ---
>  sound/soc/fsl/fsl_asrc.c     |  4 +--
>  sound/soc/fsl/fsl_asrc.h     |  3 ++
>  sound/soc/fsl/fsl_asrc_dma.c | 64 ++++++++++++++++++++++++++++++++----
>  3 files changed, 62 insertions(+), 9 deletions(-)
> 
> diff --git a/sound/soc/fsl/fsl_asrc.c b/sound/soc/fsl/fsl_asrc.c
> index 584badf956d2..0bf91a6f54b9 100644
> --- a/sound/soc/fsl/fsl_asrc.c
> +++ b/sound/soc/fsl/fsl_asrc.c
> @@ -115,7 +115,7 @@ static void fsl_asrc_sel_proc(int inrate, int outrate,
>   * within range [ANCA, ANCA+ANCB-1], depends on the channels of pair A
>   * while pair A and pair C are comparatively independent.
>   */
> -static int fsl_asrc_request_pair(int channels, struct fsl_asrc_pair *pair)
> +int fsl_asrc_request_pair(int channels, struct fsl_asrc_pair *pair)
>  {
>  	enum asrc_pair_index index = ASRC_INVALID_PAIR;
>  	struct fsl_asrc *asrc_priv = pair->asrc_priv;
> @@ -158,7 +158,7 @@ static int fsl_asrc_request_pair(int channels, struct fsl_asrc_pair *pair)
>   *
>   * It clears the resource from asrc_priv and releases the occupied channels.
>   */
> -static void fsl_asrc_release_pair(struct fsl_asrc_pair *pair)
> +void fsl_asrc_release_pair(struct fsl_asrc_pair *pair)
>  {
>  	struct fsl_asrc *asrc_priv = pair->asrc_priv;
>  	enum asrc_pair_index index = pair->index;
> diff --git a/sound/soc/fsl/fsl_asrc.h b/sound/soc/fsl/fsl_asrc.h
> index 38af485bdd22..2b57e8c53728 100644
> --- a/sound/soc/fsl/fsl_asrc.h
> +++ b/sound/soc/fsl/fsl_asrc.h
> @@ -462,4 +462,7 @@ struct fsl_asrc {
>  #define DRV_NAME "fsl-asrc-dai"
>  extern struct snd_soc_component_driver fsl_asrc_component;
>  struct dma_chan *fsl_asrc_get_dma_channel(struct fsl_asrc_pair *pair, bool dir);
> +int fsl_asrc_request_pair(int channels, struct fsl_asrc_pair *pair);
> +void fsl_asrc_release_pair(struct fsl_asrc_pair *pair);
> +
>  #endif /* _FSL_ASRC_H */
> diff --git a/sound/soc/fsl/fsl_asrc_dma.c b/sound/soc/fsl/fsl_asrc_dma.c
> index 01052a0808b0..2a60fc6142b1 100644
> --- a/sound/soc/fsl/fsl_asrc_dma.c
> +++ b/sound/soc/fsl/fsl_asrc_dma.c
> @@ -16,13 +16,11 @@
>  
>  #define FSL_ASRC_DMABUF_SIZE	(256 * 1024)
>  
> -static const struct snd_pcm_hardware snd_imx_hardware = {
> +static struct snd_pcm_hardware snd_imx_hardware = {
>  	.info = SNDRV_PCM_INFO_INTERLEAVED |
>  		SNDRV_PCM_INFO_BLOCK_TRANSFER |
>  		SNDRV_PCM_INFO_MMAP |
> -		SNDRV_PCM_INFO_MMAP_VALID |
> -		SNDRV_PCM_INFO_PAUSE |
> -		SNDRV_PCM_INFO_RESUME,
> +		SNDRV_PCM_INFO_MMAP_VALID,
>  	.buffer_bytes_max = FSL_ASRC_DMABUF_SIZE,
>  	.period_bytes_min = 128,
>  	.period_bytes_max = 65535, /* Limited by SDMA engine */
> @@ -270,12 +268,25 @@ static int fsl_asrc_dma_hw_free(struct snd_pcm_substream *substream)
>  
>  static int fsl_asrc_dma_startup(struct snd_pcm_substream *substream)
>  {
> +	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
>  	struct snd_soc_pcm_runtime *rtd = substream->private_data;
>  	struct snd_pcm_runtime *runtime = substream->runtime;
>  	struct snd_soc_component *component = snd_soc_rtdcom_lookup(rtd, DRV_NAME);
> +	struct snd_dmaengine_dai_dma_data *dma_data;
>  	struct device *dev = component->dev;
>  	struct fsl_asrc *asrc_priv = dev_get_drvdata(dev);
>  	struct fsl_asrc_pair *pair;
> +	struct dma_chan *tmp_chan = NULL;
> +	u8 dir = tx ? OUT : IN;
> +	bool release_pair = true;
> +	int ret = 0;
> +
> +	ret = snd_pcm_hw_constraint_integer(substream->runtime,
> +					    SNDRV_PCM_HW_PARAM_PERIODS);
> +	if (ret < 0) {
> +		dev_err(dev, "failed to set pcm hw params periods\n");
> +		return ret;
> +	}
>  
>  	pair = kzalloc(sizeof(struct fsl_asrc_pair), GFP_KERNEL);
>  	if (!pair)
> @@ -285,11 +296,50 @@ static int fsl_asrc_dma_startup(struct snd_pcm_substream *substream)
>  
>  	runtime->private_data = pair;
>  
> -	snd_pcm_hw_constraint_integer(substream->runtime,
> -				      SNDRV_PCM_HW_PARAM_PERIODS);
> +	/* Request a dummy pair, which will be released later.
> +	 * Request pair function needs channel num as input, for this
> +	 * dummy pair, we just request "1" channel temporarily.
> +	 */
> +	ret = fsl_asrc_request_pair(1, pair);
> +	if (ret < 0) {
> +		dev_err(dev, "failed to request asrc pair\n");
> +		goto req_pair_err;
> +	}
> +
> +	/* Request a dummy dma channel, which will be released later. */
> +	tmp_chan = fsl_asrc_get_dma_channel(pair, dir);
> +	if (!tmp_chan) {
> +		dev_err(dev, "failed to get dma channel\n");
> +		ret = -EINVAL;
> +		goto dma_chan_err;
> +	}
> +
> +	dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
> +
> +	/* Refine the snd_imx_hardware according to caps of DMA. */
> +	ret = snd_dmaengine_pcm_refine_runtime_hwparams(substream,
> +							dma_data,
> +							&snd_imx_hardware,
> +							tmp_chan);
> +	if (ret < 0) {
> +		dev_err(dev, "failed to refine runtime hwparams\n");
> +		goto out;
> +	}
> +
> +	release_pair = false;
>  	snd_soc_set_runtime_hwparams(substream, &snd_imx_hardware);
>  
> -	return 0;
> +out:
> +	dma_release_channel(tmp_chan);
> +
> +dma_chan_err:
> +	fsl_asrc_release_pair(pair);
> +
> +req_pair_err:
> +	if (release_pair)
> +		kfree(pair);
> +
> +	return ret;
>  }
>  
>  static int fsl_asrc_dma_shutdown(struct snd_pcm_substream *substream)
> -- 
> 2.21.0
>