ASoC: cs35l32: avoid uninitialized variable access

Message ID 2884997.s8B8BuE04L@wuerfel
State New
Headers show

Commit Message

Arnd Bergmann Jan. 1, 2016, 11:19 p.m.
gcc warns about the possibilty of accessing a property read from
devicetree in cs35l32_i2c_probe() when it has not been initialized
because CONFIG_OF is disabled:

sound/soc/codecs/cs35l32.c: In function 'cs35l32_i2c_probe':
sound/soc/codecs/cs35l32.c:278:2: warning: 'val' may be used uninitialized in this function [-Wmaybe-uninitialized]

The code is actually correct because it checks the dev->of_node
variable first and we know this is NULL here, but by adding a
check for IS_ENABLED(CONFIG_OF), we can let the compiler know
as well, and also generate smaller object code.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>



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Comments

Mark Brown Jan. 2, 2016, 2:17 p.m. | #1
On Sat, Jan 02, 2016 at 12:19:52AM +0100, Arnd Bergmann wrote:

> -		if (i2c_client->dev.of_node) {

> +		if (IS_ENABLED(CONFIG_OF) && i2c_client->dev.of_node) {


This would be a lot nicer if there was an __always_null annotation we
could put on of_node for !OF configurations, that'd Just Work and this
can't be the only case where we have this idiom.

Patch

diff --git a/sound/soc/codecs/cs35l32.c b/sound/soc/codecs/cs35l32.c
index 44c30fe3e315..52ffaa8eb02b 100644
--- a/sound/soc/codecs/cs35l32.c
+++ b/sound/soc/codecs/cs35l32.c
@@ -372,7 +372,7 @@  static int cs35l32_i2c_probe(struct i2c_client *i2c_client,
 			dev_err(&i2c_client->dev, "could not allocate pdata\n");
 			return -ENOMEM;
 		}
-		if (i2c_client->dev.of_node) {
+		if (IS_ENABLED(CONFIG_OF) && i2c_client->dev.of_node) {
 			ret = cs35l32_handle_of_data(i2c_client,
 						     &cs35l32->pdata);
 			if (ret != 0)