ALSA: ice1724 - constrain runtime rates for locked internal rate

The driver already defines control "Multi Track Rate Locking" which
locks the card at current rate if switched to internal clock. This patch
limits the runtime rates to this rate only, allowing proper reporting
of the card capabilities, and e.g. automatic rate conversion by the plug
plugin to the currently locked rate.

Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/ice1712/ice1724.c

@@ -1013,6 +1013,25 @@ static int set_rate_constraints(struct snd_ice1712 *ice,
 					  ice->hw_rates);
 }
 
+/* if the card has the internal rate locked (is_pro_locked), limit runtime
+   hw rates to the current internal rate only.
+*/
+static void constrain_rate_if_locked(struct snd_pcm_substream *substream)
+{
+	struct snd_ice1712 *ice = snd_pcm_substream_chip(substream);
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	unsigned int rate;
+	if (is_pro_rate_locked(ice)) {
+		rate = ice->get_rate(ice);
+		if (rate >= runtime->hw.rate_min
+		    && rate <= runtime->hw.rate_max) {
+			runtime->hw.rate_min = rate;
+			runtime->hw.rate_max = rate;
+		}
+	}
+}
+
+
 /* multi-channel playback needs alignment 8x32bit regardless of the channels
  * actually used
  */
@@ -1046,6 +1065,7 @@ static int snd_vt1724_playback_pro_open(struct snd_pcm_substream *substream)
 				   VT1724_BUFFER_ALIGN);
 	snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
 				   VT1724_BUFFER_ALIGN);
+	constrain_rate_if_locked(substream);
 	if (ice->pro_open)
 		ice->pro_open(ice, substream);
 	return 0;
@@ -1066,6 +1086,7 @@ static int snd_vt1724_capture_pro_open(struct snd_pcm_substream *substream)
 				   VT1724_BUFFER_ALIGN);
 	snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
 				   VT1724_BUFFER_ALIGN);
+	constrain_rate_if_locked(substream);
 	if (ice->pro_open)
 		ice->pro_open(ice, substream);
 	return 0;
@@ -1215,6 +1236,7 @@ static int snd_vt1724_playback_spdif_open(struct snd_pcm_substream *substream)
 				   VT1724_BUFFER_ALIGN);
 	snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
 				   VT1724_BUFFER_ALIGN);
+	constrain_rate_if_locked(substream);
 	if (ice->spdif.ops.open)
 		ice->spdif.ops.open(ice, substream);
 	return 0;
@@ -1251,6 +1273,7 @@ static int snd_vt1724_capture_spdif_open(struct snd_pcm_substream *substream)
 				   VT1724_BUFFER_ALIGN);
 	snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
 				   VT1724_BUFFER_ALIGN);
+	constrain_rate_if_locked(substream);
 	if (ice->spdif.ops.open)
 		ice->spdif.ops.open(ice, substream);
 	return 0;