1 files changed, 54 insertions, 25 deletions

diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index 6bcf5af6edce..8b2e4160de8d 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -859,13 +859,18 @@ static void azx_stream_start(struct azx *chip, struct azx_dev *azx_dev)
                       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 @@ static int azx_setup_periods(struct azx *chip,
         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 @@ static int azx_setup_periods(struct azx *chip,
  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 @@ static int azx_setup_controller(struct azx *chip, struct azx_dev *azx_dev)
         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 @@ static int azx_pcm_open(struct snd_pcm_substream *substream)
         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_close(struct snd_pcm_substream *substream)
 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 @@ static int azx_pcm_hw_free(struct snd_pcm_substream *substream)
         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 @@ static int azx_pcm_prepare(struct snd_pcm_substream *substream)
         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;