From: Takashi Iwai tiwai@suse.de
commit dc0dc8a73e8e4dc33fba93dfe23356cc5a500c57 upstream.
The recent fix c4824ae7db41 ("ALSA: pcm: Fix mmap capability check") restricts the mmap capability only to the drivers that properly set up the buffers, but it caused a regression for a few drivers that manage the buffer on its own way.
For those with UNKNOWN buffer type (i.e. the uninitialized / unused substream->dma_buffer), just assume that the driver handles the mmap properly and blindly trust the hardware info bit.
Fixes: c4824ae7db41 ("ALSA: pcm: Fix mmap capability check") Reported-and-tested-by: Jeff Woods jwoods@fnordco.com Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/s5him0gpghv.wl-tiwai@suse.de Signed-off-by: Takashi Iwai tiwai@suse.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- sound/core/pcm_native.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
--- a/sound/core/pcm_native.c +++ b/sound/core/pcm_native.c @@ -251,7 +251,10 @@ static bool hw_support_mmap(struct snd_p
switch (substream->dma_buffer.dev.type) { case SNDRV_DMA_TYPE_UNKNOWN: - return false; + /* we can't know the device, so just assume that the driver does + * everything right + */ + return true; case SNDRV_DMA_TYPE_CONTINUOUS: case SNDRV_DMA_TYPE_VMALLOC: return true;