Re: [alsa-devel] [PATCH 06/15] ALSA: pcm: Add DRM helper to set constraint for format

On Tue, 01 Dec 2015 18:47:02 +0100, Subhransu S. Prusty wrote:

+static int eld_limit_formats(struct snd_pcm_runtime *runtime, void *eld) +{

• u64 formats = SNDRV_PCM_FMTBIT_S16_LE;
• int i;
• const u8 *sad, *eld_buf = eld;
• sad = drm_eld_sad(eld_buf);
• if (!sad)

• goto format_constraint;
  

• for (i = drm_eld_sad_count(eld_buf); i > 0; i--, sad += 3) {

• if (sad_format(sad) == 1) { /* AUDIO_CODING_TYPE_LPCM */
  

• 	/* 20 bit */
  

• 	if (sad_sample_bits_lpcm(sad) & 0x2)
  

• 		formats |= SNDRV_PCM_FMTBIT_S32_LE;
  

• 	/* 24 bit */
  

• 	if (sad_sample_bits_lpcm(sad) & 0x4)
  

• 		formats |= SNDRV_PCM_FMTBIT_S24_LE;
  

Does it work correctly with HD-audio...?

Takashi