Commit 6111fd23 authored Nov 04, 2019 by Takashi Iwai

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: 425da159 ("ALSA: pcm: use dma_can_mmap() to check if a device supports dma_mmap_*")
Fixes: 42e748a0 ("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>

parent 6c94f380

sound/core/pcm_native.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -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);

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