FAILED: patch "[PATCH] ASoC: hdac_hda: Restore the codec device type on unbind" failed to apply to 6.6-stable tree

FAILED: patch "[PATCH] ASoC: hdac_hda: Restore the codec device type on unbind" failed to apply to 6.6-stable tree

[Sasha Levin]

The patch below does not apply to the 6.6-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 <stable@vger.kernel.org>.

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-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 08a44bde821d4fe22c0b6e63da04b3c59ac243a8
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '20261107053955-failed-6.6-08a44bde821d@kernel.org' --subject-prefix 'PATCH 6.6.y' 'HEAD^..'

Thanks,
Sasha

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

From 08a44bde821d4fe22c0b6e63da04b3c59ac243a8 Mon Sep 17 00:00:00 2001
From: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Date: Tue, 27 Oct 2026 10:38:39 +0200
Subject: [PATCH] ASoC: hdac_hda: Restore the codec device type on unbind

hdac_hda_codec_probe() changes the type of the codec device to
HDA_DEV_ASOC to prevent snd_hda_codec_unregister() from unregistering
the device when the card is freed.

The type is never restored, and hda_bus_match() requires the device and
driver types to be equal. After unbinding the codec driver via sysfs the
HDA_DEV_LEGACY codec drivers no longer match the device and bind fails
with -ENODEV.

Restore HDA_DEV_LEGACY with a device managed action registered before
the component, so it runs after the component and the card are gone.

Fixes: b60ee2e281b6 ("ASoC: hdac_hda: overwrite hdev type to HDA_DEV_ASOC")
Cc: stable@vger.kernel.org
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://patch.msgid.link/20261027083840.28813-3-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 sound/soc/codecs/hdac_hda.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/sound/soc/codecs/hdac_hda.c b/sound/soc/codecs/hdac_hda.c
index 46617fc88277e..cae5711e979c3 100644
--- a/sound/soc/codecs/hdac_hda.c
+++ b/sound/soc/codecs/hdac_hda.c
@@ -617,6 +617,13 @@ static const struct snd_soc_component_driver hdac_hda_hdmi_codec = {
 	.endianness		= 1,
 };
 
+static void hdac_hda_restore_dev_type(void *data)
+{
+	struct hdac_device *hdev = data;
+
+	hdev->type = HDA_DEV_LEGACY;
+}
+
 static int hdac_hda_dev_probe(struct hdac_device *hdev)
 {
 	struct hdac_hda_priv *hda_pvt;
@@ -634,6 +641,11 @@ static int hdac_hda_dev_probe(struct hdac_device *hdev)
 		hda_pvt->need_display_power = true;
 	dev_set_drvdata(&hdev->dev, hda_pvt);
 
+	/* Allow the legacy codec driver to match again after unbind */
+	ret = devm_add_action(&hdev->dev, hdac_hda_restore_dev_type, hdev);
+	if (ret)
+		return ret;
+
 	/* hold the ref while we probe */
 	hlink = snd_hdac_ext_bus_get_hlink_by_name(hdev->bus, dev_name(&hdev->dev));
 	if (!hlink) {
-- 
2.53.0

[PATCH 6.6.y 1/2] ASoC: hdac_hda: Allocate the private data at codec driver bind

[Sasha Levin]

From: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>

[ Upstream commit 7d357eae973a1e1933f81f55aa1b3b4e3064570f ]

The SOF HDA code allocates struct hdac_hda_priv and stores it as drvdata
of the codec device before the codec driver is bound. The driver core
clears drvdata on unbind, so after unbinding the codec driver via sysfs
a subsequent bind dereferences a NULL pointer in hdac_hda_dev_probe().

All information in the private data can be derived from the codec
device itself, so allocate and set it up in hdac_hda_dev_probe() as a
device managed resource, which is released on unbind.

Remove the allocation from SOF, keeping the check for iDisp codecs
without display audio component.

Fixes: 3fd63658caed ("ASoC: Intel: Drop hdac_ext usage for codec device creation")
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://patch.msgid.link/20261027083840.28813-2-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Omit the dev_index initialization because the private structure has no
such member and the firmware patch loader that uses it is absent. Keep
the allocation tied to codec driver binding and preserve the existing
iDisp audio-component check.

Stable-dep-of: 08a44bde821d ("ASoC: hdac_hda: Restore the codec device type on unbind")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 sound/soc/codecs/hdac_hda.c     | 12 +++++++++++-
 sound/soc/sof/intel/hda-codec.c | 22 ++++------------------
 2 files changed, 15 insertions(+), 19 deletions(-)

diff --git a/sound/soc/codecs/hdac_hda.c b/sound/soc/codecs/hdac_hda.c
index a3229a51eef33..5a196a756aaf4 100644
--- a/sound/soc/codecs/hdac_hda.c
+++ b/sound/soc/codecs/hdac_hda.c
@@ -606,10 +606,20 @@ static const struct snd_soc_component_driver hdac_hda_hdmi_codec = {
 
 static int hdac_hda_dev_probe(struct hdac_device *hdev)
 {
-	struct hdac_hda_priv *hda_pvt = dev_get_drvdata(&hdev->dev);
+	struct hdac_hda_priv *hda_pvt;
 	struct hdac_ext_link *hlink;
 	int ret;
 
+	hda_pvt = devm_kzalloc(&hdev->dev, sizeof(*hda_pvt), GFP_KERNEL);
+	if (!hda_pvt)
+		return -ENOMEM;
+
+	hda_pvt->codec = dev_to_hda_codec(&hdev->dev);
+	/* Intel iDisp (HDMI/DP) codec */
+	if (((hdev->vendor_id >> 16) & 0xFFFF) == 0x8086)
+		hda_pvt->need_display_power = true;
+	dev_set_drvdata(&hdev->dev, hda_pvt);
+
 	/* hold the ref while we probe */
 	hlink = snd_hdac_ext_bus_get_hlink_by_name(hdev->bus, dev_name(&hdev->dev));
 	if (!hlink) {
diff --git a/sound/soc/sof/intel/hda-codec.c b/sound/soc/sof/intel/hda-codec.c
index 82a6707fb4b80..0bb9e547127ba 100644
--- a/sound/soc/sof/intel/hda-codec.c
+++ b/sound/soc/sof/intel/hda-codec.c
@@ -15,8 +15,6 @@
 #include "hda.h"
 
 #if IS_ENABLED(CONFIG_SND_SOC_SOF_HDA_AUDIO_CODEC)
-#include "../../codecs/hdac_hda.h"
-
 #define CODEC_PROBE_RETRIES	3
 
 #define IDISP_VID_INTEL	0x80860000
@@ -139,7 +137,6 @@ static struct hda_codec *hda_codec_device_init(struct hdac_bus *bus, int addr, i
 /* probe individual codec */
 static int hda_codec_probe(struct snd_sof_dev *sdev, int address)
 {
-	struct hdac_hda_priv *hda_priv;
 	struct hda_bus *hbus = sof_to_hbus(sdev);
 	struct hda_codec *codec;
 	u32 hda_cmd = (address << 28) | (AC_NODE_ROOT << 20) |
@@ -159,26 +156,15 @@ static int hda_codec_probe(struct snd_sof_dev *sdev, int address)
 	dev_dbg(sdev->dev, "HDA codec #%d probed OK: response: %x\n",
 		address, resp);
 
-	hda_priv = devm_kzalloc(sdev->dev, sizeof(*hda_priv), GFP_KERNEL);
-	if (!hda_priv)
-		return -ENOMEM;
-
 	codec = hda_codec_device_init(&hbus->core, address, HDA_DEV_LEGACY);
 	ret = PTR_ERR_OR_ZERO(codec);
 	if (ret < 0)
 		return ret;
 
-	hda_priv->codec = codec;
-	dev_set_drvdata(&codec->core.dev, hda_priv);
-
-	if ((resp & 0xFFFF0000) == IDISP_VID_INTEL) {
-		if (!hbus->core.audio_component) {
-			dev_dbg(sdev->dev,
-				"iDisp hw present but no driver\n");
-			ret = -ENOENT;
-			goto out;
-		}
-		hda_priv->need_display_power = true;
+	if ((resp & 0xFFFF0000) == IDISP_VID_INTEL && !hbus->core.audio_component) {
+		dev_dbg(sdev->dev, "iDisp hw present but no driver\n");
+		ret = -ENOENT;
+		goto out;
 	}
 
 	if (is_generic_config(hbus))
-- 
2.53.0

[PATCH 6.6.y 2/2] ASoC: hdac_hda: Restore the codec device type on unbind

[Sasha Levin]

From: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>

[ Upstream commit 08a44bde821d4fe22c0b6e63da04b3c59ac243a8 ]

hdac_hda_codec_probe() changes the type of the codec device to
HDA_DEV_ASOC to prevent snd_hda_codec_unregister() from unregistering
the device when the card is freed.

The type is never restored, and hda_bus_match() requires the device and
driver types to be equal. After unbinding the codec driver via sysfs the
HDA_DEV_LEGACY codec drivers no longer match the device and bind fails
with -ENODEV.

Restore HDA_DEV_LEGACY with a device managed action registered before
the component, so it runs after the component and the card are gone.

Fixes: b60ee2e281b6 ("ASoC: hdac_hda: overwrite hdev type to HDA_DEV_ASOC")
Cc: stable@vger.kernel.org
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://patch.msgid.link/20261027083840.28813-3-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 sound/soc/codecs/hdac_hda.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/sound/soc/codecs/hdac_hda.c b/sound/soc/codecs/hdac_hda.c
index 5a196a756aaf4..d39f93aefcbf3 100644
--- a/sound/soc/codecs/hdac_hda.c
+++ b/sound/soc/codecs/hdac_hda.c
@@ -604,6 +604,13 @@ static const struct snd_soc_component_driver hdac_hda_hdmi_codec = {
 	.endianness		= 1,
 };
 
+static void hdac_hda_restore_dev_type(void *data)
+{
+	struct hdac_device *hdev = data;
+
+	hdev->type = HDA_DEV_LEGACY;
+}
+
 static int hdac_hda_dev_probe(struct hdac_device *hdev)
 {
 	struct hdac_hda_priv *hda_pvt;
@@ -620,6 +627,11 @@ static int hdac_hda_dev_probe(struct hdac_device *hdev)
 		hda_pvt->need_display_power = true;
 	dev_set_drvdata(&hdev->dev, hda_pvt);
 
+	/* Allow the legacy codec driver to match again after unbind */
+	ret = devm_add_action(&hdev->dev, hdac_hda_restore_dev_type, hdev);
+	if (ret)
+		return ret;
+
 	/* hold the ref while we probe */
 	hlink = snd_hdac_ext_bus_get_hlink_by_name(hdev->bus, dev_name(&hdev->dev));
 	if (!hlink) {
-- 
2.53.0