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-rw-r--r--sound/core/isadma.c10
1 files changed, 9 insertions, 1 deletions
diff --git a/sound/core/isadma.c b/sound/core/isadma.c
index 79f0f16af33..950e19ba91f 100644
--- a/sound/core/isadma.c
+++ b/sound/core/isadma.c
@@ -85,16 +85,24 @@ EXPORT_SYMBOL(snd_dma_disable);
unsigned int snd_dma_pointer(unsigned long dma, unsigned int size)
{
unsigned long flags;
- unsigned int result;
+ unsigned int result, result1;
flags = claim_dma_lock();
clear_dma_ff(dma);
if (!isa_dma_bridge_buggy)
disable_dma(dma);
result = get_dma_residue(dma);
+ /*
+ * HACK - read the counter again and choose higher value in order to
+ * avoid reading during counter lower byte roll over if the
+ * isa_dma_bridge_buggy is set.
+ */
+ result1 = get_dma_residue(dma);
if (!isa_dma_bridge_buggy)
enable_dma(dma);
release_dma_lock(flags);
+ if (unlikely(result < result1))
+ result = result1;
#ifdef CONFIG_SND_DEBUG
if (result > size)
snd_printk(KERN_ERR "pointer (0x%x) for DMA #%ld is greater than transfer size (0x%x)\n", result, dma, size);