Re: [PATCH] backlight: adp8860: fix another uninitialized variable use

["Jingoo Han" <jingoohan1@gmail.com>]

On Tuesday, December 01, 2015 6:33 PM, Michael Hennerich wrote:
> On 11/30/2015 12:24 PM, Arnd Bergmann wrote:
> > A recent patch I did fixed two potential uses of uninitialized
> > variables in the adp8870 and adp8860 drivers. Unfortunately,
> > I missed another one:
> >
> > drivers/video/backlight/adp8860_bl.c: In function 'adp8860_bl_ambient_light_level_show':
> > drivers/video/backlight/adp8860_bl.c:570:11: warning: 'reg_val' may be used uninitialized in this
> function
> >
> > This does the same change as before in one additional function,
> > and also changes the check for the return value in a way that
> > avoids another false positive warning with a similar message.
> >
> > Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> 
> Acked-by: Michael Hennerich <michael.hennerich@analog.com>

Acked-by: Jingoo Han <jingoohan1@gmail.com>

Best regards,
Jingoo Han

> 
> > Fixes: 6be3a5a9cd91 ("backlight: adp88x0: Fix uninitialized variable use")
> > ---
> > Sorry for missing this third hunk the first time around.
> >
> > diff --git a/drivers/video/backlight/adp8860_bl.c b/drivers/video/backlight/adp8860_bl.c
> > index f0d4c0324580..510e559c060e 100644
> > --- a/drivers/video/backlight/adp8860_bl.c
> > +++ b/drivers/video/backlight/adp8860_bl.c
> > @@ -566,11 +566,13 @@ static ssize_t adp8860_bl_ambient_light_level_show(struct device *dev,
> >
> >   	mutex_lock(&data->lock);
> >   	error = adp8860_read(data->client, ADP8860_PH1LEVL, &reg_val);
> > -	ret_val = reg_val;
> > -	error |= adp8860_read(data->client, ADP8860_PH1LEVH, &reg_val);
> > +	if (!error) {
> > +		ret_val = reg_val;
> > +		error = adp8860_read(data->client, ADP8860_PH1LEVH, &reg_val);
> > +	}
> >   	mutex_unlock(&data->lock);
> >
> > -	if (error < 0)
> > +	if (error)
> >   		return error;
> >
> >   	/* Return 13-bit conversion value for the first light sensor */
> >
> 
> 
> --
> Greetings,
> Michael
> 
> --
> Analog Devices GmbH      Wilhelm-Wagenfeld-Str. 6      80807 Muenchen
> Sitz der Gesellschaft: Muenchen; Registergericht: Muenchen HRB 40368;
> Geschaeftsfuehrer:Dr.Carsten Suckrow, Thomas Wessel, William A. Martin,
> Margaret Seif