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

BugLink: https://bugs.launchpad.net/bugs/1860490
[ Upstream commit 6111fd2370eecae9f11bfdc08ba097e0b51fcfd3 ]

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: 425da159707b ("ALSA: pcm: use dma_can_mmap() to check if a device supports dma_mmap_*")
Fixes: 42e748a0b325 ("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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index 38541322ccec63b40c6fe826a8cff457dd958266..86700fce07527e444c5a4bc6f547dc99b8a1a5c7 100644 (file)
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -223,7 +223,8 @@ static bool hw_support_mmap(struct snd_pcm_substream *substream)
        /* architecture supports dma_mmap_coherent()? */
 #if defined(CONFIG_ARCH_NO_COHERENT_DMA_MMAP) || !defined(CONFIG_HAS_DMA)
        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 false;
 #endif
        return true;