[PATCH 4.19 023/103] ALSA: dice: fix fallback from protocol extension into limited functionality

Greg Kroah-Hartman
2020-01-22T09:47:24Z

From: Takashi Sakamoto <o-takashi@sakamocchi.jp>

commit 3e2dc6bdb56893bc28257e482e1dbe5d39f313df upstream.

At failure of attempt to detect protocol extension, ALSA dice driver
should be fallback to limited functionality. However it's not.

This commit fixes it.

Cc: <stable@vger.kernel.org> # v4.18+
Fixes: 58579c056c1c9 ("ALSA: dice: use extended protocol to detect available stream formats")
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20200113084630.14305-2-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
sound/firewire/dice/dice-extension.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

--- a/sound/firewire/dice/dice-extension.c
+++ b/sound/firewire/dice/dice-extension.c
@@ -159,8 +159,11 @@ int snd_dice_detect_extension_formats(st
int j;

for (j = i + 1; j < 9; ++j) {
- if (pointers[i * 2] == pointers[j * 2])
+ if (pointers[i * 2] == pointers[j * 2]) {
+ // Fallback to limited functionality.
+ err = -ENXIO;
goto end;
+ }
}
}