ALSA: ali5451: Fix out-of-bound position reporting

The pointer callbacks of ali5451 driver may return the value at the
boundary occasionally, and it results in the kernel warning like
  snd_ali5451 0000:00:06.0: BUG: , pos = 16384, buffer size = 16384, period size = 1024

It seems that folding the position offset is enough for fixing the
warning and no ill-effect has been seen by that.

Reported-by: Enrico Mioso <mrkiko.rs@gmail.com>
Tested-by: Enrico Mioso <mrkiko.rs@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 2 insertions, 0 deletions

diff --git a/sound/pci/ali5451/ali5451.c b/sound/pci/ali5451/ali5451.c
index 36470af7eda7..92b819e4f729 100644
--- a/sound/pci/ali5451/ali5451.c
+++ b/sound/pci/ali5451/ali5451.c
@@ -1408,6 +1408,7 @@ snd_ali_playback_pointer(struct snd_pcm_substream *substream)
         spin_unlock(&codec->reg_lock);
         dev_dbg(codec->card->dev, "playback pointer returned cso=%xh.\n", cso);
 
+        cso %= runtime->buffer_size;
         return cso;
 }
 
@@ -1428,6 +1429,7 @@ static snd_pcm_uframes_t snd_ali_pointer(struct snd_pcm_substream *substream)
         cso = inw(ALI_REG(codec, ALI_CSO_ALPHA_FMS + 2));
         spin_unlock(&codec->reg_lock);
 
+        cso %= runtime->buffer_size;
         return cso;
 }