[PATCH] ASoC: tlv320aic3x - fix variable may be used uninitialized warning

[PATCH] ASoC: tlv320aic3x - fix variable may be used uninitialized warning

[Axel Lin]

If aic3x_read failed , val is used uninitialized.
Fix it by initializing val to 0.

This patch fixes below compile warning:
sound/soc/codecs/tlv320aic3x.c: In function 'aic3x_get_gpio':
sound/soc/codecs/tlv320aic3x.c:1183: warning: 'val' may be used uninitialized in this function
sound/soc/codecs/tlv320aic3x.c: In function 'aic3x_headset_detected':
sound/soc/codecs/tlv320aic3x.c:1211: warning: 'val' may be used uninitialized in this function
sound/soc/codecs/tlv320aic3x.c: In function 'aic3x_button_pressed':
sound/soc/codecs/tlv320aic3x.c:1219: warning: 'val' may be used uninitialized in this function

Signed-off-by: Axel Lin <axel.lin@gmail.com>
---
 sound/soc/codecs/tlv320aic3x.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/sound/soc/codecs/tlv320aic3x.c b/sound/soc/codecs/tlv320aic3x.c
index bfd036a..9de7c38 100644
--- a/sound/soc/codecs/tlv320aic3x.c
+++ b/sound/soc/codecs/tlv320aic3x.c
@@ -1180,7 +1180,7 @@ EXPORT_SYMBOL_GPL(aic3x_set_gpio);
 int aic3x_get_gpio(struct snd_soc_codec *codec, int gpio)
 {
 	u8 reg = gpio ? AIC3X_GPIO2_REG : AIC3X_GPIO1_REG;
-	u8 val, bit = gpio ? 2: 1;
+	u8 val = 0, bit = gpio ? 2 : 1;
 
 	aic3x_read(codec, reg, &val);
 	return (val >> bit) & 1;
@@ -1208,7 +1208,7 @@ EXPORT_SYMBOL_GPL(aic3x_set_headset_detection);
 
 int aic3x_headset_detected(struct snd_soc_codec *codec)
 {
-	u8 val;
+	u8 val = 0;
 	aic3x_read(codec, AIC3X_HEADSET_DETECT_CTRL_B, &val);
 	return (val >> 4) & 1;
 }
@@ -1216,7 +1216,7 @@ EXPORT_SYMBOL_GPL(aic3x_headset_detected);
 
 int aic3x_button_pressed(struct snd_soc_codec *codec)
 {
-	u8 val;
+	u8 val = 0;
 	aic3x_read(codec, AIC3X_HEADSET_DETECT_CTRL_B, &val);
 	return (val >> 5) & 1;
 }
-- 
1.7.2

Re: [PATCH] ASoC: tlv320aic3x - fix variable may be used uninitialized warning

[Mark Brown]

On Wed, Nov 24, 2010 at 10:40:59PM +0800, Axel Lin wrote:
> If aic3x_read failed , val is used uninitialized.
> Fix it by initializing val to 0.
> 
> This patch fixes below compile warning:
> sound/soc/codecs/tlv320aic3x.c: In function 'aic3x_get_gpio':
> sound/soc/codecs/tlv320aic3x.c:1183: warning: 'val' may be used uninitialized in this function
> sound/soc/codecs/tlv320aic3x.c: In function 'aic3x_headset_detected':
> sound/soc/codecs/tlv320aic3x.c:1211: warning: 'val' may be used uninitialized in this function
> sound/soc/codecs/tlv320aic3x.c: In function 'aic3x_button_pressed':
> sound/soc/codecs/tlv320aic3x.c:1219: warning: 'val' may be used uninitialized in this function

This does rather look like a compiler bug.  I'm generally against this
sort of change as it just tramples over the warning in cases where it
may be valid, though given the trivially small functions here it's hard
to care.

Really this stuff should all be written to use the standard jack and
GPIO APIs anyway.

Re: [PATCH] ASoC: tlv320aic3x - fix variable may be used uninitialized warning

[Mark Brown]

On Wed, Nov 24, 2010 at 10:40:59PM +0800, Axel Lin wrote:
> If aic3x_read failed , val is used uninitialized.
> Fix it by initializing val to 0.
> 
> This patch fixes below compile warning:
> sound/soc/codecs/tlv320aic3x.c: In function 'aic3x_get_gpio':
> sound/soc/codecs/tlv320aic3x.c:1183: warning: 'val' may be used uninitialized in this function
> sound/soc/codecs/tlv320aic3x.c: In function 'aic3x_headset_detected':
> sound/soc/codecs/tlv320aic3x.c:1211: warning: 'val' may be used uninitialized in this function
> sound/soc/codecs/tlv320aic3x.c: In function 'aic3x_button_pressed':
> sound/soc/codecs/tlv320aic3x.c:1219: warning: 'val' may be used uninitialized in this function

This does rather look like a compiler bug.  I'm generally against this
sort of change as it just tramples over the warning in cases where it
may be valid, though given the trivially small functions here it's hard
to care.

Really this stuff should all be written to use the standard jack and
GPIO APIs anyway.

Re: [PATCH] ASoC: tlv320aic3x - fix variable may be used uninitialized warning

[Mark Brown]

On Wed, Nov 24, 2010 at 10:40:59PM +0800, Axel Lin wrote:
> If aic3x_read failed , val is used uninitialized.
> Fix it by initializing val to 0.

I applied this one too after Liam's ack (via IM), thanks.

Re: [PATCH] ASoC: tlv320aic3x - fix variable may be used uninitialized warning

[Mark Brown]

On Wed, Nov 24, 2010 at 10:40:59PM +0800, Axel Lin wrote:
> If aic3x_read failed , val is used uninitialized.
> Fix it by initializing val to 0.

I applied this one too after Liam's ack (via IM), thanks.