ASoC: codecs: Fix error handling in pm4125 audio codec driver

pm4125_bind() acquires references through pm4125_sdw_device_get() but
fails to release them in error paths and during normal unbind
operations. This could result in reference count leaks, preventing
proper cleanup and potentially causing resource exhaustion over
multiple bind/unbind cycles.

Calling path: pm4125_sdw_device_get() -> bus_find_device_by_of_node()
-> bus_find_device() -> get_device.

Found by code review.

Cc: stable@vger.kernel.org
Fixes: 8ad5294 ("ASoC: codecs: add new pm4125 audio codec driver")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Link: https://patch.msgid.link/20251116033716.29369-1-make24@iscas.ac.cn
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: Ma Ke

sound/soc/codecs/pm4125.c

@@ -1551,6 +1551,10 @@ static int pm4125_bind(struct device *dev)
 	struct device_link *devlink;
 	int ret;
 
+	/* Initialize device pointers to NULL for safe cleanup */
+	pm4125->rxdev = NULL;
+	pm4125->txdev = NULL;
+
 	/* Give the soundwire subdevices some more time to settle */
 	usleep_range(15000, 15010);
 
@@ -1574,7 +1578,7 @@ static int pm4125_bind(struct device *dev)
 	if (!pm4125->txdev) {
 		dev_err(dev, "could not find txslave with matching of node\n");
 		ret = -EINVAL;
-		goto error_unbind_all;
+		goto error_put_rx;
 	}
 
 	pm4125->sdw_priv[AIF1_CAP] = dev_get_drvdata(pm4125->txdev);
@@ -1584,7 +1588,7 @@ static int pm4125_bind(struct device *dev)
 	if (!pm4125->tx_sdw_dev) {
 		dev_err(dev, "could not get txslave with matching of dev\n");
 		ret = -EINVAL;
-		goto error_unbind_all;
+		goto error_put_tx;
 	}
 
 	/*
@@ -1596,7 +1600,7 @@ static int pm4125_bind(struct device *dev)
 	if (!devlink) {
 		dev_err(dev, "Could not devlink TX and RX\n");
 		ret = -EINVAL;
-		goto error_unbind_all;
+		goto error_put_tx;
 	}
 
 	devlink = device_link_add(dev, pm4125->txdev,
@@ -1650,6 +1654,10 @@ static int pm4125_bind(struct device *dev)
 	device_link_remove(dev, pm4125->txdev);
 link_remove_rx_tx:
 	device_link_remove(pm4125->rxdev, pm4125->txdev);
+error_put_tx:
+	put_device(pm4125->txdev);
+error_put_rx:
+	put_device(pm4125->rxdev);
 error_unbind_all:
 	component_unbind_all(dev, pm4125);
 	return ret;
@@ -1663,6 +1671,13 @@ static void pm4125_unbind(struct device *dev)
 	device_link_remove(dev, pm4125->txdev);
 	device_link_remove(dev, pm4125->rxdev);
 	device_link_remove(pm4125->rxdev, pm4125->txdev);
+
+	/* Release device references acquired in bind */
+	if (pm4125->txdev)
+		put_device(pm4125->txdev);
+	if (pm4125->rxdev)
+		put_device(pm4125->rxdev);
+
 	component_unbind_all(dev, pm4125);
 }