From: Rong Zhang <i@rong.moe>
Date: Sun, 5 Jul 2026 18:19:31 +0000 (+0800)
Subject: ALSA: usb-audio: Fix imbalance per-channel volume of sticky mixers
X-Git-Tag: v7.2-rc4~31^2~19
X-Git-Url: http://git.ipfire.org/gitweb/index.cgi?a=commitdiff_plain;h=ea588e4c7484ea883d3dab308f1f2c2f0f51f7d6;p=thirdparty%2Fkernel%2Flinux.git

ALSA: usb-audio: Fix imbalance per-channel volume of sticky mixers

I accidentally made an off-by-a-line mistake when mimicking other code
paths that set all channels. The mistake breaks sticky mixers with
multiple channels.

I didn't realize this mistake at that time, as my device's mixer is
single-channel.

Fix it, so that per-channel volume of sticky mixers is balanced.

Fixes: aa2f4addab44 ("ALSA: usb-audio: Set the value of potential sticky mixers to maximum")
Signed-off-by: Rong Zhang <i@rong.moe>
Link: https://patch.msgid.link/20260706-uac-sticky-channels-fix-v1-1-92741c538283@rong.moe
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---

diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c
index b4c855c25eef..703c118f9d4e 100644
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -1473,8 +1473,8 @@ sticky:
 	if (!cval->cmask) {
 		snd_usb_set_cur_mix_value(cval, 0, 0, cval->max);
 	} else {
+		idx = 0;
 		for (i = 0; i < MAX_CHANNELS; i++) {
-			idx = 0;
 			if (cval->cmask & BIT(i)) {
 				snd_usb_set_cur_mix_value(cval, i + 1, idx, cval->max);
 				idx++;