1 files changed, 18 insertions, 5 deletions

diff --git a/sound/atmel/ac97c.c b/sound/atmel/ac97c.c
index 21be9c9fbd53..4e8f66d40812 100644
--- a/sound/atmel/ac97c.c
+++ b/sound/atmel/ac97c.c
@@ -1,5 +1,5 @@
 /*
- * Driver for the Atmel AC97C controller
+ * Driver for Atmel AC97C
  *
  * Copyright (C) 2005-2009 Atmel Corporation
  *
@@ -10,6 +10,7 @@
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/bitmap.h>
+#include <linux/device.h>
 #include <linux/dmaengine.h>
 #include <linux/dma-mapping.h>
 #include <linux/init.h>
@@ -297,9 +298,11 @@ static int atmel_ac97c_playback_prepare(struct snd_pcm_substream *substream)
 {
         struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
         struct snd_pcm_runtime *runtime = substream->runtime;
-        unsigned long word = 0;
+        unsigned long word = ac97c_readl(chip, OCA);
         int retval;
 
+        word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
+
         /* assign channels to AC97C channel A */
         switch (runtime->channels) {
         case 1:
@@ -323,9 +326,13 @@ static int atmel_ac97c_playback_prepare(struct snd_pcm_substream *substream)
                 word |= AC97C_CMR_CEM_LITTLE;
                 break;
         case SNDRV_PCM_FORMAT_S16_BE: /* fall through */
-        default:
                 word &= ~(AC97C_CMR_CEM_LITTLE);
                 break;
+        default:
+                word = ac97c_readl(chip, OCA);
+                word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
+                ac97c_writel(chip, OCA, word);
+                return -EINVAL;
         }
 
         ac97c_writel(chip, CAMR, word);
@@ -358,9 +365,11 @@ static int atmel_ac97c_capture_prepare(struct snd_pcm_substream *substream)
 {
         struct atmel_ac97c *chip = snd_pcm_substream_chip(substream);
         struct snd_pcm_runtime *runtime = substream->runtime;
-        unsigned long word = 0;
+        unsigned long word = ac97c_readl(chip, ICA);
         int retval;
 
+        word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
+
         /* assign channels to AC97C channel A */
         switch (runtime->channels) {
         case 1:
@@ -384,9 +393,13 @@ static int atmel_ac97c_capture_prepare(struct snd_pcm_substream *substream)
                 word |= AC97C_CMR_CEM_LITTLE;
                 break;
         case SNDRV_PCM_FORMAT_S16_BE: /* fall through */
-        default:
                 word &= ~(AC97C_CMR_CEM_LITTLE);
                 break;
+        default:
+                word = ac97c_readl(chip, ICA);
+                word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT));
+                ac97c_writel(chip, ICA, word);
+                return -EINVAL;
         }
 
         ac97c_writel(chip, CAMR, word);