ALSA: hda - HDMI sticky stream tag support (ef18bede) · Commits · 戴 / test

When we run the following commands in turn (with CONFIG_SND_HDA_POWER_SAVE_DEFAULT=0), speaker-test -Dhw:0,3 -c2 -twav # HDMI speaker-test -Dhw:0,0 -c2 -twav # Analog The second command will produce sound in the analog lineout _as well as_ HDMI sink. The root cause is, device 0 "reuses" the same stream tag that was used by device 3, and the "intelhdmi - sticky stream id" patch leaves the HDMI codec in a functional state. So the HDMI codec happily accepts the audio samples which reuse its stream tag. The proposed solution is to remember the last device each azx_dev was assigned to, and prefer to 1) reuse the azx_dev (and hence the stream tag) the HDMI codec last used 2) or assign a never-used azx_dev for HDMI With this patch and the above two speaker-test commands, HDMI codec will use stream tag 8 and Analog codec will use 5. The stream tag used by HDMI codec won't be reused by others, as long as we don't run out of the 4 playback azx_dev's. The legacy Analog codec will continue to use stream tag 5 because its device id is 0 (this is a bit tricky). Signed-off-by:

Wu Fengguang <fengguang.wu@intel.com> Signed-off-by:

Takashi Iwai <tiwai@suse.de>

sound/pci/hda/hda_intel.c

+15 −6

Original line number	Diff line number	Diff line
		@@ -356,6 +356,7 @@ struct azx_dev {
		*/
		unsigned char stream_tag; /* assigned stream */
		unsigned char index; /* stream index */
		int device; /* last device number assigned to */

		unsigned int opened :1;
		unsigned int running :1;
		@@ -1441,10 +1442,13 @@ static int __devinit azx_codec_configure(struct azx *chip)
		*/

		/* assign a stream for the PCM */
		static inline struct azx_dev azx_assign_device(struct azx chip, int stream)
		static inline struct azx_dev *
		azx_assign_device(struct azx chip, struct snd_pcm_substream substream)
		{
		int dev, i, nums;
		if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
		struct azx_dev *res = NULL;

		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
		dev = chip->playback_index_offset;
		nums = chip->playback_streams;
		} else {
		@@ -1453,10 +1457,15 @@ static inline struct azx_dev azx_assign_device(struct azx chip, int stream)
		}
		for (i = 0; i < nums; i++, dev++)
		if (!chip->azx_dev[dev].opened) {
		chip->azx_dev[dev].opened = 1;
		return &chip->azx_dev[dev];
		res = &chip->azx_dev[dev];
		if (res->device == substream->pcm->device)
		break;
		}
		if (res) {
		res->opened = 1;
		res->device = substream->pcm->device;
		}
		return NULL;
		return res;
		}

		/* release the assigned stream */
		@@ -1505,7 +1514,7 @@ static int azx_pcm_open(struct snd_pcm_substream *substream)
		int err;

		mutex_lock(&chip->open_mutex);
		azx_dev = azx_assign_device(chip, substream->stream);
		azx_dev = azx_assign_device(chip, substream);
		if (azx_dev == NULL) {
		mutex_unlock(&chip->open_mutex);
		return -EBUSY;

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