From c4824ae7db418aee6f50f308a20b832e58e997fd Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@suse.de>
Date: Tue, 20 Jul 2021 11:26:40 +0200
Subject: [PATCH] ALSA: pcm: Fix mmap capability check
Git-commit: c4824ae7db418aee6f50f308a20b832e58e997fd
Patch-mainline: v5.14-rc3
References: git-fixes

The hw_support_mmap() doesn't cover all memory allocation types and
might use a wrong device pointer for checking the capability.
Check the all memory allocation types more completely.

Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210720092640.12338-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

---
 sound/core/pcm_native.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index c88c4316c417..6919d2943b9d 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -246,12 +246,18 @@ static bool hw_support_mmap(struct snd_pcm_substream *substream)
 	if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_MMAP))
 		return false;
 
-	if (substream->ops->mmap ||
-	    (substream->dma_buffer.dev.type != SNDRV_DMA_TYPE_DEV &&
-	     substream->dma_buffer.dev.type != SNDRV_DMA_TYPE_DEV_UC))
+	if (substream->ops->mmap)
 		return true;
 
-	return dma_can_mmap(substream->dma_buffer.dev.dev);
+	switch (substream->dma_buffer.dev.type) {
+	case SNDRV_DMA_TYPE_UNKNOWN:
+		return false;
+	case SNDRV_DMA_TYPE_CONTINUOUS:
+	case SNDRV_DMA_TYPE_VMALLOC:
+		return true;
+	default:
+		return dma_can_mmap(substream->dma_buffer.dev.dev);
+	}
 }
 
 static int constrain_mask_params(struct snd_pcm_substream *substream,
-- 
2.26.2