[PATCH 4.14 044/101] ALSA: fireface: fix for state to fetch PCM frames

From: Greg Kroah-Hartman
Date: Mon Jan 07 2019 - 08:03:32 EST

4.14-stable review patch. If anyone has any objections, please let me know.


From: Takashi Sakamoto <o-takashi@xxxxxxxxxxxxx>

commit 3d16200a3e55a39caa1c88419cb559c00316f721 upstream.

According to my memo at hand and saved records, writing 0x00000001 to
SND_FF_REG_FETCH_PCM_FRAMES disables fetching PCM frames in corresponding
channel, however current implement uses reversed logic. This results in
muted volume in device side during playback.

This commit corrects the bug.

Cc: <stable@xxxxxxxxxxxxxxx> # v4.12+
Fixes: 76fdb3a9e13a ('ALSA: fireface: add support for Fireface 400')
Signed-off-by: Takashi Sakamoto <o-takashi@xxxxxxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

sound/firewire/fireface/ff-protocol-ff400.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/sound/firewire/fireface/ff-protocol-ff400.c
+++ b/sound/firewire/fireface/ff-protocol-ff400.c
@@ -152,7 +152,7 @@ static int ff400_switch_fetching_mode(st
if (reg == NULL)
return -ENOMEM;

- if (enable) {
+ if (!enable) {
* Each quadlet is corresponding to data channels in a data
* blocks in reverse order. Precisely, quadlets for available