FAILED: patch "[PATCH] ALSA: hda: Fix cached processing coefficient verbs" failed to apply to 6.1-stable tree

The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x f67be28fdf8b5d31ac1cc1152bb17250f9f8f513
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026072011-plastic-headphone-afbf@gregkh' --subject-prefix 'PATCH 6.1.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From f67be28fdf8b5d31ac1cc1152bb17250f9f8f513 Mon Sep 17 00:00:00 2001
From: Xu Rao <[email protected]>
Date: Tue, 7 Jul 2026 21:24:19 +0800
Subject: [PATCH] ALSA: hda: Fix cached processing coefficient verbs

Intel HD Audio defines Coefficient Index and Processing Coefficient as separate audio widget controls in the Audio Widget Verb Definitions:
Coefficient Index selects the coefficient slot, while Processing Coefficient accesses the value at the selected slot.

hda_reg_read_coef() selects the slot with AC_VERB_SET_COEF_INDEX, but then uses AC_VERB_GET_COEF_INDEX for the value read. That reads back the selected index instead of the coefficient value. hda_reg_write_coef() has the same issue and builds the value write from AC_VERB_GET_COEF_INDEX instead of AC_VERB_SET_PROC_COEF.

This only affects the regmap coefficient cache path used by codecs that set codec->cache_coef. Direct coefficient helpers already use the normal SET_COEF_INDEX followed by GET_PROC_COEF or SET_PROC_COEF sequence, which is likely why this has not been noticed widely.

Use AC_VERB_GET_PROC_COEF for cached coefficient reads and AC_VERB_SET_PROC_COEF for cached coefficient writes.

index e7b866fc52c1..d6eb17aa9e08 100644
@@ -214,7 +214,7 @@ static int hda_reg_read_coef(struct hdac_device *codec, unsigned int reg,
 	err = snd_hdac_exec_verb(codec, verb, 0, NULL);
 	if (err < 0)
 		return err;
-	verb = (reg & ~0xfffff) | (AC_VERB_GET_COEF_INDEX << 8);
+	verb = (reg & ~0xfffff) | (AC_VERB_GET_PROC_COEF << 8);
 	return snd_hdac_exec_verb(codec, verb, 0, val);
 }
 

@@ -232,7 +232,7 @@ static int hda_reg_write_coef(struct hdac_device *codec, unsigned int reg,
 	err = snd_hdac_exec_verb(codec, verb, 0, NULL);
 	if (err < 0)
 		return err;
-	verb = (reg & ~0xfffff) | (AC_VERB_GET_COEF_INDEX << 8) |
+	verb = (reg & ~0xfffff) | (AC_VERB_SET_PROC_COEF << 8) |
 		(val & 0xffff);
 	return snd_hdac_exec_verb(codec, verb, 0, NULL);
 }

From: Xu Rao <[email protected]>

[ Upstream commit f67be28fdf8b5d31ac1cc1152bb17250f9f8f513 ]

Intel HD Audio defines Coefficient Index and Processing Coefficient as separate audio widget controls in the Audio Widget Verb Definitions:
Coefficient Index selects the coefficient slot, while Processing Coefficient accesses the value at the selected slot.

hda_reg_read_coef() selects the slot with AC_VERB_SET_COEF_INDEX, but then uses AC_VERB_GET_COEF_INDEX for the value read. That reads back the selected index instead of the coefficient value. hda_reg_write_coef() has the same issue and builds the value write from AC_VERB_GET_COEF_INDEX instead of AC_VERB_SET_PROC_COEF.

This only affects the regmap coefficient cache path used by codecs that set codec->cache_coef. Direct coefficient helpers already use the normal SET_COEF_INDEX followed by GET_PROC_COEF or SET_PROC_COEF sequence, which is likely why this has not been noticed widely.

Use AC_VERB_GET_PROC_COEF for cached coefficient reads and AC_VERB_SET_PROC_COEF for cached coefficient writes.

---
 sound/hda/hdac_regmap.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

index 39610a15bcc988..9b786cec8f1e13 100644
@@ -215,7 +215,7 @@ static int hda_reg_read_coef(struct hdac_device *codec, unsigned int reg,
 	err = snd_hdac_exec_verb(codec, verb, 0, NULL);
 	if (err < 0)
 		return err;
-	verb = (reg & ~0xfffff) | (AC_VERB_GET_COEF_INDEX << 8);
+	verb = (reg & ~0xfffff) | (AC_VERB_GET_PROC_COEF << 8);
 	return snd_hdac_exec_verb(codec, verb, 0, val);
 }
 

@@ -233,7 +233,7 @@ static int hda_reg_write_coef(struct hdac_device *codec, unsigned int reg,
 	err = snd_hdac_exec_verb(codec, verb, 0, NULL);
 	if (err < 0)
 		return err;
-	verb = (reg & ~0xfffff) | (AC_VERB_GET_COEF_INDEX << 8) |
+	verb = (reg & ~0xfffff) | (AC_VERB_SET_PROC_COEF << 8) |
 		(val & 0xffff);
 	return snd_hdac_exec_verb(codec, verb, 0, NULL);
 }

2.53.0