On Thu, 21 Mar 2019 17:10:07 +0100,
Pierre-Louis Bossart wrote:
>
> +/* this may get called several times by oss emulation */
> +static int sof_pcm_hw_params(struct snd_pcm_substream *substream,
> + struct snd_pcm_hw_params *params)
> +{
....
> + /* container size */
> + switch (params_width(params)) {
> + case 16:
> + pcm.params.sample_container_bytes = 2;
> + break;
> + case 24:
> + pcm.params.sample_container_bytes = 4;
> + break;
> + case 32:
> + pcm.params.sample_container_bytes = 4;
> + break;
> + default:
> + return -EINVAL;
> + }
This can be simply snd_pcm_format_physical_width() / 8.
> +static int sof_pcm_open(struct snd_pcm_substream *substream)
> +{
....
> + /* set any runtime constraints based on topology */
> + snd_pcm_hw_constraint_step(substream->runtime, 0,
> + SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
> + le32_to_cpu(caps->period_size_min));
> + snd_pcm_hw_constraint_step(substream->runtime, 0,
> + SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
> + le32_to_cpu(caps->period_size_min));
Is period_size_min in frames or in bytes? The code below refers as
byte size while this refers as frames, so they look inconsistent.
> +
> + /* set runtime config */
> + runtime->hw.info = SNDRV_PCM_INFO_MMAP |
> + SNDRV_PCM_INFO_MMAP_VALID |
> + SNDRV_PCM_INFO_INTERLEAVED |
> + SNDRV_PCM_INFO_PAUSE |
> + SNDRV_PCM_INFO_RESUME |
> + SNDRV_PCM_INFO_NO_PERIOD_WAKEUP;
Does SOF support the full resume? That is, the stream gets resumed at
the exact position that was suspended. Most devices can't, hence they
don't set *_INFO_RESUME flag and let user-space restarting.
> + runtime->hw.period_bytes_min = le32_to_cpu(caps->period_size_min);
> + runtime->hw.period_bytes_max = le32_to_cpu(caps->period_size_max);
> + runtime->hw.periods_min = le32_to_cpu(caps->periods_min);
> + runtime->hw.periods_max = le32_to_cpu(caps->periods_max);
> + runtime->hw.buffer_bytes_max = le32_to_cpu(caps->buffer_size_max);
These refer as bytes...
thanks,
Takashi
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