[patch] ALSA: hda ca0132 - remove unused error handling code

[patch] ALSA: hda ca0132 - remove unused error handling code

[Dan Carpenter]

We never save the return value from chipio_write() so "err" is always
zero here, not less than zero.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
The other option would be to save the return value.  I don't have the
hardware and I worried that there was a reason we don't save it.  The
current code is misleading because it looks like it's checked until
you notice that the "err = " bit is missing.

diff --git a/sound/pci/hda/patch_ca0132.c b/sound/pci/hda/patch_ca0132.c
index 35abe3c..92f1f0c 100644
--- a/sound/pci/hda/patch_ca0132.c
+++ b/sound/pci/hda/patch_ca0132.c
@@ -733,8 +733,6 @@ static int ca0132_hp_switch_put(struct snd_kcontrol *kcontrol,
 	/* *valp 0 is mute, 1 is unmute */
 	data = (data & 0x7f) | (*valp ? 0 : 0x80);
 	chipio_write(codec, REG_CODEC_MUTE, data);
-	if (err < 0)
-		return err;
 
 	spec->curr_hp_switch = *valp;
 
@@ -775,8 +773,6 @@ static int ca0132_speaker_switch_put(struct snd_kcontrol *kcontrol,
 	/* *valp 0 is mute, 1 is unmute */
 	data = (data & 0xef) | (*valp ? 0 : 0x10);
 	chipio_write(codec, REG_CODEC_MUTE, data);
-	if (err < 0)
-		return err;
 
 	spec->curr_speaker_switch = *valp;
 
@@ -824,14 +820,10 @@ static int ca0132_hp_volume_put(struct snd_kcontrol *kcontrol,
 	val = 31 - left_vol;
 	data = (data & 0xe0) | val;
 	chipio_write(codec, REG_CODEC_HP_VOL_L, data);
-	if (err < 0)
-		return err;
 
 	val = 31 - right_vol;
 	data = (data & 0xe0) | val;
 	chipio_write(codec, REG_CODEC_HP_VOL_R, data);
-	if (err < 0)
-		return err;
 
 	spec->curr_hp_volume[0] = left_vol;
 	spec->curr_hp_volume[1] = right_vol;

Re: [patch] ALSA: hda ca0132 - remove unused error handling code

[Takashi Iwai]

At Tue, 7 Feb 2012 10:19:32 +0300,
Dan Carpenter wrote:
> 
> We never save the return value from chipio_write() so "err" is always
> zero here, not less than zero.
> 
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> The other option would be to save the return value. 

Yes, this should be a better option.  chipio_write() may fail indeed.

But then your report spotted another bug.  It doesn't handle
snd_hda_power_up|down() correctly in the error path.  It must be fixed
as well.

I'll fix these all up.

> I don't have the
> hardware and I worried that there was a reason we don't save it.  The
> current code is misleading because it looks like it's checked until
> you notice that the "err = " bit is missing.


thanks,

Takashi

> 
> diff --git a/sound/pci/hda/patch_ca0132.c b/sound/pci/hda/patch_ca0132.c
> index 35abe3c..92f1f0c 100644
> --- a/sound/pci/hda/patch_ca0132.c
> +++ b/sound/pci/hda/patch_ca0132.c
> @@ -733,8 +733,6 @@ static int ca0132_hp_switch_put(struct snd_kcontrol *kcontrol,
>  	/* *valp 0 is mute, 1 is unmute */
>  	data = (data & 0x7f) | (*valp ? 0 : 0x80);
>  	chipio_write(codec, REG_CODEC_MUTE, data);
> -	if (err < 0)
> -		return err;
>  
>  	spec->curr_hp_switch = *valp;
>  
> @@ -775,8 +773,6 @@ static int ca0132_speaker_switch_put(struct snd_kcontrol *kcontrol,
>  	/* *valp 0 is mute, 1 is unmute */
>  	data = (data & 0xef) | (*valp ? 0 : 0x10);
>  	chipio_write(codec, REG_CODEC_MUTE, data);
> -	if (err < 0)
> -		return err;
>  
>  	spec->curr_speaker_switch = *valp;
>  
> @@ -824,14 +820,10 @@ static int ca0132_hp_volume_put(struct snd_kcontrol *kcontrol,
>  	val = 31 - left_vol;
>  	data = (data & 0xe0) | val;
>  	chipio_write(codec, REG_CODEC_HP_VOL_L, data);
> -	if (err < 0)
> -		return err;
>  
>  	val = 31 - right_vol;
>  	data = (data & 0xe0) | val;
>  	chipio_write(codec, REG_CODEC_HP_VOL_R, data);
> -	if (err < 0)
> -		return err;
>  
>  	spec->curr_hp_volume[0] = left_vol;
>  	spec->curr_hp_volume[1] = right_vol;
> 

Re: [patch] ALSA: hda ca0132 - remove unused error handling code

[Takashi Iwai]

At Tue, 07 Feb 2012 10:59:48 +0100,
Takashi Iwai wrote:
> 
> At Tue, 7 Feb 2012 10:19:32 +0300,
> Dan Carpenter wrote:
> > 
> > We never save the return value from chipio_write() so "err" is always
> > zero here, not less than zero.
> > 
> > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> > ---
> > The other option would be to save the return value. 
> 
> Yes, this should be a better option.  chipio_write() may fail indeed.
> 
> But then your report spotted another bug.  It doesn't handle
> snd_hda_power_up|down() correctly in the error path.  It must be fixed
> as well.
> 
> I'll fix these all up.

FWIW, below is the fix patch.


Takashi

---
From: Takashi Iwai <tiwai@suse.de>
Subject: [PATCH] ALSA: hda - Fix error handling in patch_ca0132.c

In patch_ca0132.c, the error returned from chipio_write() isn't checked
always.  Also, the power-up/down sequence isn't tracked properly in some
error paths.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
 sound/pci/hda/patch_ca0132.c |   33 +++++++++++++++++++--------------
 1 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/sound/pci/hda/patch_ca0132.c b/sound/pci/hda/patch_ca0132.c
index 35abe3c..21d91d5 100644
--- a/sound/pci/hda/patch_ca0132.c
+++ b/sound/pci/hda/patch_ca0132.c
@@ -728,18 +728,19 @@ static int ca0132_hp_switch_put(struct snd_kcontrol *kcontrol,
 
 	err = chipio_read(codec, REG_CODEC_MUTE, &data);
 	if (err < 0)
-		return err;
+		goto exit;
 
 	/* *valp 0 is mute, 1 is unmute */
 	data = (data & 0x7f) | (*valp ? 0 : 0x80);
-	chipio_write(codec, REG_CODEC_MUTE, data);
+	err = chipio_write(codec, REG_CODEC_MUTE, data);
 	if (err < 0)
-		return err;
+		goto exit;
 
 	spec->curr_hp_switch = *valp;
 
+ exit:
 	snd_hda_power_down(codec);
-	return 1;
+	return err < 0 ? err : 1;
 }
 
 static int ca0132_speaker_switch_get(struct snd_kcontrol *kcontrol,
@@ -770,18 +771,19 @@ static int ca0132_speaker_switch_put(struct snd_kcontrol *kcontrol,
 
 	err = chipio_read(codec, REG_CODEC_MUTE, &data);
 	if (err < 0)
-		return err;
+		goto exit;
 
 	/* *valp 0 is mute, 1 is unmute */
 	data = (data & 0xef) | (*valp ? 0 : 0x10);
-	chipio_write(codec, REG_CODEC_MUTE, data);
+	err = chipio_write(codec, REG_CODEC_MUTE, data);
 	if (err < 0)
-		return err;
+		goto exit;
 
 	spec->curr_speaker_switch = *valp;
 
+ exit:
 	snd_hda_power_down(codec);
-	return 1;
+	return err < 0 ? err : 1;
 }
 
 static int ca0132_hp_volume_get(struct snd_kcontrol *kcontrol,
@@ -819,25 +821,26 @@ static int ca0132_hp_volume_put(struct snd_kcontrol *kcontrol,
 
 	err = chipio_read(codec, REG_CODEC_HP_VOL_L, &data);
 	if (err < 0)
-		return err;
+		goto exit;
 
 	val = 31 - left_vol;
 	data = (data & 0xe0) | val;
-	chipio_write(codec, REG_CODEC_HP_VOL_L, data);
+	err = chipio_write(codec, REG_CODEC_HP_VOL_L, data);
 	if (err < 0)
-		return err;
+		goto exit;
 
 	val = 31 - right_vol;
 	data = (data & 0xe0) | val;
-	chipio_write(codec, REG_CODEC_HP_VOL_R, data);
+	err = chipio_write(codec, REG_CODEC_HP_VOL_R, data);
 	if (err < 0)
-		return err;
+		goto exit;
 
 	spec->curr_hp_volume[0] = left_vol;
 	spec->curr_hp_volume[1] = right_vol;
 
+ exit:
 	snd_hda_power_down(codec);
-	return 1;
+	return err < 0 ? err : 1;
 }
 
 static int add_hp_switch(struct hda_codec *codec, hda_nid_t nid)
@@ -936,6 +939,8 @@ static int ca0132_build_controls(struct hda_codec *codec)
 		if (err < 0)
 			return err;
 		err = add_in_volume(codec, spec->dig_in, "IEC958");
+		if (err < 0)
+			return err;
 	}
 	return 0;
 }
-- 
1.7.9.rc2