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ALSA: pcm: Fix missing check of the new non-cached buffer type 

The check for the mmap support via hw_support_mmap() function misses
the case where the device is with SNDRV_DMA_TYPE_DEV_UC, which should
have been treated equally as SNDRV_DMA_TYPE_DEV.  Let's fix it.

Note that this bug doesn't hit any practical problem, because
SNDRV_DMA_TYPE_DEV_UC is used only for x86-specific drivers
(snd-hda-intel and snd-intel8x0) for the specific platforms that need
the non-cached buffers.  And, on such platforms, hw_support_mmap()
already returns true in anyway.  That's the reason I didn't put
Cc-to-stable mark here.  This is only for any theoretical future
extension.

Fixes: 425da15970 ("ALSA: pcm: use dma_can_mmap() to check if a device supports dma_mmap_*")
Fixes: 42e748a0b3 ("ALSA: memalloc: Add non-cached buffer type")
Link: https://lore.kernel.org/r/20191104101115.27311-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Iwai 2019-11-04 11:11:15 +01:00
parent 6c94f380c6
commit 6111fd2370
1 changed files with 2 additions and 1 deletions
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3
sound/core/pcm_native.c
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@ -222,7 +222,8 @@ static bool hw_support_mmap(struct snd_pcm_substream *substream)
return false;
if (substream->ops->mmap ||
substream->dma_buffer.dev.type != SNDRV_DMA_TYPE_DEV)
(substream->dma_buffer.dev.type != SNDRV_DMA_TYPE_DEV &&
substream->dma_buffer.dev.type != SNDRV_DMA_TYPE_DEV_UC))
return true;
return dma_can_mmap(substream->dma_buffer.dev.dev);