dmix - Enable auto format detection as default

The direct plugins have the automatic format-detection feature but it
wasn't enabled properly in the interface.  Now you can pass the format
"unchanged" to make the plugin detect a proper format.

This will change the default format of some drivers, such as, HD-audio.

2 files changed, 10 insertions, 4 deletions

diff --git a/src/pcm/pcm_direct.c b/src/pcm/pcm_direct.c
index 75d540d4..a884b120 100644
--- a/src/pcm/pcm_direct.c
+++ b/src/pcm/pcm_direct.c
@@ -874,7 +874,11 @@ int snd_pcm_direct_initialize_slave(snd_pcm_direct_t *dmix, snd_pcm_t *spcm, str
 			return ret;
 		}
 	}
-	ret = snd_pcm_hw_params_set_format(spcm, hw_params, params->format);
+	if (params->format == SND_PCM_FORMAT_UNKNOWN)
+		ret = -EINVAL;
+	else
+		ret = snd_pcm_hw_params_set_format(spcm, hw_params,
+						   params->format);
 	if (ret < 0) {
 		static const snd_pcm_format_t dmix_formats[] = {
 			SND_PCM_FORMAT_S32,
diff --git a/src/pcm/pcm_dmix.c b/src/pcm/pcm_dmix.c
index e54cf922..4d21e9ba 100644
--- a/src/pcm/pcm_dmix.c
+++ b/src/pcm/pcm_dmix.c
@@ -1267,7 +1267,7 @@ int _snd_pcm_dmix_open(snd_pcm_t **pcmp, const char *name,
 	params.periods = 3;
 
 	err = snd_pcm_slave_conf(root, dopen.slave, &sconf, 8,
-				 SND_PCM_HW_PARAM_FORMAT, 0, &params.format,
+				 SND_PCM_HW_PARAM_FORMAT, SCONF_UNCHANGED, &params.format,
 				 SND_PCM_HW_PARAM_RATE, 0, &params.rate,
 				 SND_PCM_HW_PARAM_CHANNELS, 0, &params.channels,
 				 SND_PCM_HW_PARAM_PERIOD_TIME, 0, &params.period_time,
@@ -1282,8 +1282,10 @@ int _snd_pcm_dmix_open(snd_pcm_t **pcmp, const char *name,
 	if (psize == -1 && params.period_time == -1)
 		params.period_time = 125000;    /* 0.125 seconds */
 
-	/* sorry, limited features */
-	if (! (dmix_supported_format & (1ULL << params.format))) {
+	if (params.format == -2)
+		params.format = SND_PCM_FORMAT_UNKNOWN;
+	else if (!(dmix_supported_format & (1ULL << params.format))) {
+		/* sorry, limited features */
 		SNDERR("Unsupported format");
 		snd_config_delete(sconf);
 		return -EINVAL;