From 50d50d189a357a9c8b3e453a3e724ee2e382414e Mon Sep 17 00:00:00 2001
From: Clemens Ladisch <clemens@ladisch.de>
Date: Wed, 24 Mar 2010 07:10:54 +0100
Subject: [PATCH] --- yaml --- r: 188931 b: refs/heads/master c:
 1c583063a5c769fe2ec604752e383972c69e6d9b h: refs/heads/master i:   188929:
 158b969356ed07687aec76fb52bded549f8f5704   188927:
 7056ffa98e2521b71508afa7844e7cee4ee8f370 v: v3

---
 [refs]                   |  2 +-
 trunk/sound/pci/cmipci.c | 14 +++++++++++---
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/[refs] b/[refs]
index 9a7dd475abf3..c30711cdab87 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: fc8aa7b16a5fcfe9c6d0be9bb587f1fcedd9145f
+refs/heads/master: 1c583063a5c769fe2ec604752e383972c69e6d9b
diff --git a/trunk/sound/pci/cmipci.c b/trunk/sound/pci/cmipci.c
index 1ded64e05643..329968edca9b 100644
--- a/trunk/sound/pci/cmipci.c
+++ b/trunk/sound/pci/cmipci.c
@@ -941,13 +941,21 @@ static snd_pcm_uframes_t snd_cmipci_pcm_pointer(struct cmipci *cm, struct cmipci
 						struct snd_pcm_substream *substream)
 {
 	size_t ptr;
-	unsigned int reg;
+	unsigned int reg, rem, tries;
+
 	if (!rec->running)
 		return 0;
 #if 1 // this seems better..
 	reg = rec->ch ? CM_REG_CH1_FRAME2 : CM_REG_CH0_FRAME2;
-	ptr = rec->dma_size - (snd_cmipci_read_w(cm, reg) + 1);
-	ptr >>= rec->shift;
+	for (tries = 0; tries < 3; tries++) {
+		rem = snd_cmipci_read_w(cm, reg);
+		if (rem < rec->dma_size)
+			goto ok;
+	} 
+	printk(KERN_ERR "cmipci: invalid PCM pointer: %#x\n", rem);
+	return SNDRV_PCM_POS_XRUN;
+ok:
+	ptr = (rec->dma_size - (rem + 1)) >> rec->shift;
 #else
 	reg = rec->ch ? CM_REG_CH1_FRAME1 : CM_REG_CH0_FRAME1;
 	ptr = snd_cmipci_read(cm, reg) - rec->offset;