Merge branch 'topic/hda-optimize' into topic/hda
diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index 6bcf5af..8b2e416 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -859,13 +859,18 @@
 		      SD_CTL_DMA_START | SD_INT_MASK);
 }
 
-/* stop a stream */
-static void azx_stream_stop(struct azx *chip, struct azx_dev *azx_dev)
+/* stop DMA */
+static void azx_stream_clear(struct azx *chip, struct azx_dev *azx_dev)
 {
-	/* stop DMA */
 	azx_sd_writeb(azx_dev, SD_CTL, azx_sd_readb(azx_dev, SD_CTL) &
 		      ~(SD_CTL_DMA_START | SD_INT_MASK));
 	azx_sd_writeb(azx_dev, SD_STS, SD_INT_MASK); /* to be sure */
+}
+
+/* stop a stream */
+static void azx_stream_stop(struct azx *chip, struct azx_dev *azx_dev)
+{
+	azx_stream_clear(chip, azx_dev);
 	/* disable SIE */
 	azx_writeb(chip, INTCTL,
 		   azx_readb(chip, INTCTL) & ~(1 << azx_dev->index));
@@ -1076,8 +1081,7 @@
 	azx_sd_writel(azx_dev, SD_BDLPL, 0);
 	azx_sd_writel(azx_dev, SD_BDLPU, 0);
 
-	period_bytes = snd_pcm_lib_period_bytes(substream);
-	azx_dev->period_bytes = period_bytes;
+	period_bytes = azx_dev->period_bytes;
 	periods = azx_dev->bufsize / period_bytes;
 
 	/* program the initial BDL entries */
@@ -1124,24 +1128,17 @@
  error:
 	snd_printk(KERN_ERR "Too many BDL entries: buffer=%d, period=%d\n",
 		   azx_dev->bufsize, period_bytes);
-	/* reset */
-	azx_sd_writel(azx_dev, SD_BDLPL, 0);
-	azx_sd_writel(azx_dev, SD_BDLPU, 0);
 	return -EINVAL;
 }
 
-/*
- * set up the SD for streaming
- */
-static int azx_setup_controller(struct azx *chip, struct azx_dev *azx_dev)
+/* reset stream */
+static void azx_stream_reset(struct azx *chip, struct azx_dev *azx_dev)
 {
 	unsigned char val;
 	int timeout;
 
-	/* make sure the run bit is zero for SD */
-	azx_sd_writeb(azx_dev, SD_CTL, azx_sd_readb(azx_dev, SD_CTL) &
-		      ~SD_CTL_DMA_START);
-	/* reset stream */
+	azx_stream_clear(chip, azx_dev);
+
 	azx_sd_writeb(azx_dev, SD_CTL, azx_sd_readb(azx_dev, SD_CTL) |
 		      SD_CTL_STREAM_RESET);
 	udelay(3);
@@ -1158,7 +1155,15 @@
 	while (((val = azx_sd_readb(azx_dev, SD_CTL)) & SD_CTL_STREAM_RESET) &&
 	       --timeout)
 		;
+}
 
+/*
+ * set up the SD for streaming
+ */
+static int azx_setup_controller(struct azx *chip, struct azx_dev *azx_dev)
+{
+	/* make sure the run bit is zero for SD */
+	azx_stream_clear(chip, azx_dev);
 	/* program the stream_tag */
 	azx_sd_writel(azx_dev, SD_CTL,
 		      (azx_sd_readl(azx_dev, SD_CTL) & ~SD_CTL_STREAM_TAG_MASK)|
@@ -1403,6 +1408,8 @@
 	runtime->private_data = azx_dev;
 	snd_pcm_set_sync(substream);
 	mutex_unlock(&chip->open_mutex);
+
+	azx_stream_reset(chip, azx_dev);
 	return 0;
 }
 
@@ -1429,6 +1436,11 @@
 static int azx_pcm_hw_params(struct snd_pcm_substream *substream,
 			     struct snd_pcm_hw_params *hw_params)
 {
+	struct azx_dev *azx_dev = get_azx_dev(substream);
+
+	azx_dev->bufsize = 0;
+	azx_dev->period_bytes = 0;
+	azx_dev->format_val = 0;
 	return snd_pcm_lib_malloc_pages(substream,
 					params_buffer_bytes(hw_params));
 }
@@ -1443,6 +1455,9 @@
 	azx_sd_writel(azx_dev, SD_BDLPL, 0);
 	azx_sd_writel(azx_dev, SD_BDLPU, 0);
 	azx_sd_writel(azx_dev, SD_CTL, 0);
+	azx_dev->bufsize = 0;
+	azx_dev->period_bytes = 0;
+	azx_dev->format_val = 0;
 
 	hinfo->ops.cleanup(hinfo, apcm->codec, substream);
 
@@ -1456,23 +1471,37 @@
 	struct azx_dev *azx_dev = get_azx_dev(substream);
 	struct hda_pcm_stream *hinfo = apcm->hinfo[substream->stream];
 	struct snd_pcm_runtime *runtime = substream->runtime;
+	unsigned int bufsize, period_bytes, format_val;
+	int err;
 
-	azx_dev->bufsize = snd_pcm_lib_buffer_bytes(substream);
-	azx_dev->format_val = snd_hda_calc_stream_format(runtime->rate,
-							 runtime->channels,
-							 runtime->format,
-							 hinfo->maxbps);
-	if (!azx_dev->format_val) {
+	format_val = snd_hda_calc_stream_format(runtime->rate,
+						runtime->channels,
+						runtime->format,
+						hinfo->maxbps);
+	if (!format_val) {
 		snd_printk(KERN_ERR SFX
 			   "invalid format_val, rate=%d, ch=%d, format=%d\n",
 			   runtime->rate, runtime->channels, runtime->format);
 		return -EINVAL;
 	}
 
+	bufsize = snd_pcm_lib_buffer_bytes(substream);
+	period_bytes = snd_pcm_lib_period_bytes(substream);
+
 	snd_printdd("azx_pcm_prepare: bufsize=0x%x, format=0x%x\n",
-		    azx_dev->bufsize, azx_dev->format_val);
-	if (azx_setup_periods(chip, substream, azx_dev) < 0)
-		return -EINVAL;
+		    bufsize, format_val);
+
+	if (bufsize != azx_dev->bufsize ||
+	    period_bytes != azx_dev->period_bytes ||
+	    format_val != azx_dev->format_val) {
+		azx_dev->bufsize = bufsize;
+		azx_dev->period_bytes = period_bytes;
+		azx_dev->format_val = format_val;
+		err = azx_setup_periods(chip, substream, azx_dev);
+		if (err < 0)
+			return err;
+	}
+
 	azx_setup_controller(chip, azx_dev);
 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 		azx_dev->fifo_size = azx_sd_readw(azx_dev, SD_FIFOSIZE) + 1;