[alsa-devel] [PATCH] ASoC: Fix cs4270 error path

[Jean Delvare]

The error path in cs4270_probe/cs4270_remove is pretty broken:
* If cs4270_probe fails, codec is leaked.
* If snd_soc_register_card fails, cs4270_i2c_driver stays registered.
* If I2C support is enabled but no I2C device is found, i2c_del_driver
  is never called (neither in cs4270_probe nor in cs4270_remove.)

Fix the first 2 problems by implementing a clean error path in
cs4270_probe and jumping to its labels as needed. Fix the 3rd problem
by removing the condition to call i2c_del_driver in cs4270_remove.

Signed-off-by: Jean Delvare <khali at linux-fr.org>
---
Timur, can you please review and test this patch? I do not have the
hardware so I couldn't test it myself.

 sound/soc/codecs/cs4270.c |   25 ++++++++++++++++++-------
 1 file changed, 18 insertions(+), 7 deletions(-)

--- linux-2.6.27-rc5.orig/sound/soc/codecs/cs4270.c	2008-08-31 13:59:17.000000000 +0200
+++ linux-2.6.27-rc5/sound/soc/codecs/cs4270.c	2008-08-31 14:23:34.000000000 +0200
@@ -727,7 +727,7 @@ static int cs4270_probe(struct platform_
 	ret = snd_soc_new_pcms(socdev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1);
 	if (ret < 0) {
 		printk(KERN_ERR "cs4270: failed to create PCMs\n");
-		return ret;
+		goto error_free_codec;
 	}
 
 #ifdef USE_I2C
@@ -736,8 +736,7 @@ static int cs4270_probe(struct platform_
 	ret = i2c_add_driver(&cs4270_i2c_driver);
 	if (ret) {
 		printk(KERN_ERR "cs4270: failed to attach driver");
-		snd_soc_free_pcms(socdev);
-		return ret;
+		goto error_free_pcms;
 	}
 
 	/* Did we find a CS4270 on the I2C bus? */
@@ -759,10 +758,23 @@ static int cs4270_probe(struct platform_
 	ret = snd_soc_register_card(socdev);
 	if (ret < 0) {
 		printk(KERN_ERR "cs4270: failed to register card\n");
-		snd_soc_free_pcms(socdev);
-		return ret;
+		goto error_del_driver;
 	}
 
+	return 0;
+
+error_del_driver:
+#ifdef USE_I2C
+	i2c_del_driver(&cs4270_i2c_driver);
+
+error_free_pcms:
+#endif
+	snd_soc_free_pcms(socdev);
+
+error_free_codec:
+	kfree(socdev->codec);
+	socdev->codec = NULL;
+
 	return ret;
 }
 
@@ -773,8 +785,7 @@ static int cs4270_remove(struct platform
 	snd_soc_free_pcms(socdev);
 
 #ifdef USE_I2C
-	if (socdev->codec->control_data)
-		i2c_del_driver(&cs4270_i2c_driver);
+	i2c_del_driver(&cs4270_i2c_driver);
 #endif
 
 	kfree(socdev->codec);


-- 
Jean Delvare