ALSA: hda: cs35l56: Fix uninitialized value in cs35l56_hda_read_acpi()

[ Upstream commit 90df495 ]

Eliminate the uninitialized 'nval' in cs35l56_hda_read_acpi() if a
system-specific quirk overrides processing of the dev-index property.
The value is now stored in a new 'num_amps' member of struct cs35l56_hda
so that the quirk handler can set the value.

The quirk for the Lenovo Yoga Book 9i GenX  replaces the values from the
dev-index property with hardcoded indexes. So cs35l56_hda_read_acpi() would
then skip reading the property. But this left the 'nval' local variable
uninitialized when it is later passed to cirrus_scodec_get_speaker_id().

Fixes: 40b1c2f ("ALSA: hda/cs35l56: Workaround bad dev-index on Lenovo Yoga Book 9i GenX")
Reported-by: Dan Carpenter <error27@gmail.com>
Closes: https://lore.kernel.org/linux-sound/aenFesLAStjrVNy8@stanley.mountain/T/#u
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://patch.msgid.link/20260428130531.169600-1-rf@opensource.cirrus.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: rfvirgil

sound/pci/hda/cs35l56_hda.c

@@ -888,6 +888,7 @@ static int cs35l56_hda_system_resume(struct device *dev)
 static int cs35l56_hda_fixup_yoga9(struct cs35l56_hda *cs35l56, int *bus_addr)
 {
 	/* The cirrus,dev-index property has the wrong values */
+	cs35l56->num_amps = 2;
 	switch (*bus_addr) {
 	case 0x30:
 		cs35l56->index = 1;
@@ -937,7 +938,6 @@ static int cs35l56_hda_read_acpi(struct cs35l56_hda *cs35l56, int hid, int id)
 	char hid_string[8];
 	struct acpi_device *adev;
 	const char *property, *sub;
-	size_t nval;
 	int i, ret;
 
 	/*
@@ -973,13 +973,14 @@ static int cs35l56_hda_read_acpi(struct cs35l56_hda *cs35l56, int hid, int id)
 			ret = -EINVAL;
 			goto err;
 		}
-		nval = ret;
+		cs35l56->num_amps = ret;
 
-		ret = device_property_read_u32_array(cs35l56->base.dev, property, values, nval);
+		ret = device_property_read_u32_array(cs35l56->base.dev, property, values,
+						     cs35l56->num_amps);
 		if (ret)
 			goto err;
 
-		for (i = 0; i < nval; i++) {
+		for (i = 0; i < cs35l56->num_amps; i++) {
 			if (values[i] == id) {
 				cs35l56->index = i;
 				break;
@@ -1002,7 +1003,8 @@ static int cs35l56_hda_read_acpi(struct cs35l56_hda *cs35l56, int hid, int id)
 			 "Read ACPI _SUB failed(%ld): fallback to generic firmware\n",
 			 PTR_ERR(sub));
 	} else {
-		ret = cirrus_scodec_get_speaker_id(cs35l56->base.dev, cs35l56->index, nval, -1);
+		ret = cirrus_scodec_get_speaker_id(cs35l56->base.dev, cs35l56->index,
+						   cs35l56->num_amps, -1);
 		if (ret == -ENOENT) {
 			cs35l56->system_name = sub;
 		} else if (ret >= 0) {

sound/pci/hda/cs35l56_hda.h

@@ -25,6 +25,7 @@ struct cs35l56_hda {
 	struct work_struct dsp_work;
 
 	int index;
+	int num_amps;
 	const char *system_name;
 	const char *amp_name;