1 files changed, 51 insertions, 9 deletions

diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c
index 86d0caf91b35..3420bd3da5d7 100644
--- a/sound/core/pcm_lib.c
+++ b/sound/core/pcm_lib.c
@@ -23,6 +23,7 @@
 #include <linux/slab.h>
 #include <linux/time.h>
 #include <linux/math64.h>
+#include <linux/export.h>
 #include <sound/core.h>
 #include <sound/control.h>
 #include <sound/info.h>
@@ -1399,6 +1400,32 @@ int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
 
 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
 
+static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
+					   struct snd_pcm_hw_rule *rule)
+{
+	unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
+	struct snd_interval *rate;
+
+	rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
+	return snd_interval_list(rate, 1, &base_rate, 0);
+}
+
+/**
+ * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
+ * @runtime: PCM runtime instance
+ * @base_rate: the rate at which the hardware does not resample
+ */
+int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
+			       unsigned int base_rate)
+{
+	return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
+				   SNDRV_PCM_HW_PARAM_RATE,
+				   snd_pcm_hw_rule_noresample_func,
+				   (void *)(uintptr_t)base_rate,
+				   SNDRV_PCM_HW_PARAM_RATE, -1);
+}
+EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
+
 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
 				  snd_pcm_hw_param_t var)
 {
@@ -1761,6 +1788,10 @@ static int wait_for_avail(struct snd_pcm_substream *substream,
 	snd_pcm_uframes_t avail = 0;
 	long wait_time, tout;
 
+	init_waitqueue_entry(&wait, current);
+	set_current_state(TASK_INTERRUPTIBLE);
+	add_wait_queue(&runtime->tsleep, &wait);
+
 	if (runtime->no_period_wakeup)
 		wait_time = MAX_SCHEDULE_TIMEOUT;
 	else {
@@ -1771,16 +1802,32 @@ static int wait_for_avail(struct snd_pcm_substream *substream,
 		}
 		wait_time = msecs_to_jiffies(wait_time * 1000);
 	}
-	init_waitqueue_entry(&wait, current);
-	add_wait_queue(&runtime->tsleep, &wait);
+
 	for (;;) {
 		if (signal_pending(current)) {
 			err = -ERESTARTSYS;
 			break;
 		}
+
+		/*
+		 * We need to check if space became available already
+		 * (and thus the wakeup happened already) first to close
+		 * the race of space already having become available.
+		 * This check must happen after been added to the waitqueue
+		 * and having current state be INTERRUPTIBLE.
+		 */
+		if (is_playback)
+			avail = snd_pcm_playback_avail(runtime);
+		else
+			avail = snd_pcm_capture_avail(runtime);
+		if (avail >= runtime->twake)
+			break;
 		snd_pcm_stream_unlock_irq(substream);
-		tout = schedule_timeout_interruptible(wait_time);
+
+		tout = schedule_timeout(wait_time);
+
 		snd_pcm_stream_lock_irq(substream);
+		set_current_state(TASK_INTERRUPTIBLE);
 		switch (runtime->status->state) {
 		case SNDRV_PCM_STATE_SUSPENDED:
 			err = -ESTRPIPE;
@@ -1806,14 +1853,9 @@ static int wait_for_avail(struct snd_pcm_substream *substream,
 			err = -EIO;
 			break;
 		}
-		if (is_playback)
-			avail = snd_pcm_playback_avail(runtime);
-		else
-			avail = snd_pcm_capture_avail(runtime);
-		if (avail >= runtime->twake)
-			break;
 	}
  _endloop:
+	set_current_state(TASK_RUNNING);
 	remove_wait_queue(&runtime->tsleep, &wait);
 	*availp = avail;
 	return err;