On Mon, 23 Nov 2015, Arnd Bergmann wrote: > gcc correctly warns about both the adp8860 and adp8870 backlight > drivers using an uninitialized variable in their error handling > path: > > drivers/video/backlight/adp8870_bl.c: In function > 'adp8870_bl_ambient_light_zone_store': > drivers/video/backlight/adp8870_bl.c:811:11: warning: 'reg_val' may be used > uninitialized in this function > > This changes the code to only write back the data if it was > correctly read to start with. > > As a side-note, the drivers are mostly identical, so I think they > should really be merged into one file to avoid having to fix every > bug twice. > > Signed-off-by: Arnd Bergmann <a...@arndb.de>
Applied, thanks. > diff --git a/drivers/video/backlight/adp8860_bl.c > b/drivers/video/backlight/adp8860_bl.c > index 98ffe71e8af2..f0d4c0324580 100644 > --- a/drivers/video/backlight/adp8860_bl.c > +++ b/drivers/video/backlight/adp8860_bl.c > @@ -621,10 +621,12 @@ static ssize_t > adp8860_bl_ambient_light_zone_store(struct device *dev, > > /* Set user supplied ambient light zone */ > mutex_lock(&data->lock); > - adp8860_read(data->client, ADP8860_CFGR, ®_val); > - reg_val &= ~(CFGR_BLV_MASK << CFGR_BLV_SHIFT); > - reg_val |= (val - 1) << CFGR_BLV_SHIFT; > - adp8860_write(data->client, ADP8860_CFGR, reg_val); > + ret = adp8860_read(data->client, ADP8860_CFGR, ®_val); > + if (!ret) { > + reg_val &= ~(CFGR_BLV_MASK << CFGR_BLV_SHIFT); > + reg_val |= (val - 1) << CFGR_BLV_SHIFT; > + adp8860_write(data->client, ADP8860_CFGR, reg_val); > + } > mutex_unlock(&data->lock); > } > > diff --git a/drivers/video/backlight/adp8870_bl.c > b/drivers/video/backlight/adp8870_bl.c > index 9d738352d7d4..21acac90fd77 100644 > --- a/drivers/video/backlight/adp8870_bl.c > +++ b/drivers/video/backlight/adp8870_bl.c > @@ -807,10 +807,12 @@ static ssize_t > adp8870_bl_ambient_light_zone_store(struct device *dev, > > /* Set user supplied ambient light zone */ > mutex_lock(&data->lock); > - adp8870_read(data->client, ADP8870_CFGR, ®_val); > - reg_val &= ~(CFGR_BLV_MASK << CFGR_BLV_SHIFT); > - reg_val |= (val - 1) << CFGR_BLV_SHIFT; > - adp8870_write(data->client, ADP8870_CFGR, reg_val); > + ret = adp8870_read(data->client, ADP8870_CFGR, ®_val); > + if (!ret) { > + reg_val &= ~(CFGR_BLV_MASK << CFGR_BLV_SHIFT); > + reg_val |= (val - 1) << CFGR_BLV_SHIFT; > + adp8870_write(data->client, ADP8870_CFGR, reg_val); > + } > mutex_unlock(&data->lock); > } > > -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/