| Message ID | 20180725073830.31421-1-daniel.thompson@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | [v4] backlight: pwm_bl: Fix uninitialized variable | expand |
On Wed, 25 Jul 2018, Daniel Thompson wrote: > Currently, if the DT does not define num-interpolated-steps then > num_steps is undefined and the interpolation code will deploy randomly. > Fix with a simple initialize to zero. > > Fixes: 573fe6d1c25c ("backlight: pwm_bl: Linear interpolation between brightness-levels") > Reported-by: Marcel Ziswiler <marcel.ziswiler@toradex.com> > Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> > Tested-by: Marcel Ziswiler <marcel.ziswiler@toradex.com> > Reviewed-by: Douglas Anderson <dianders@chromium.org> > Acked-by: Lee Jones <lee.jones@linaro.org> > --- > > Notes: > v4: > - Remove line break from Fixes: and update the *-by:s > > v3: > - Switch to the simplest fix and zero the uninitialized variable. git > grep indicates that ~25% of calls to of_property_read_u32() use this > pattern (pre-initialize optional properties with sane values and > ignore the return code). > > v2: > - Simplify SoB chain (with Marcel's permission) > - Separate complex if statement and make other similar calls use same > return code checking approach > - Tidy up comment formatting and fix pre-existing grammar error > > drivers/video/backlight/pwm_bl.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) Applied, thanks. -- Lee Jones [李琼斯] Linaro Services Technical Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog
diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c index 9ee4c1b735b2..bdfcc0a71db1 100644 --- a/drivers/video/backlight/pwm_bl.c +++ b/drivers/video/backlight/pwm_bl.c @@ -250,7 +250,7 @@ static int pwm_backlight_parse_dt(struct device *dev, struct device_node *node = dev->of_node; unsigned int num_levels = 0; unsigned int levels_count; - unsigned int num_steps; + unsigned int num_steps = 0; struct property *prop; unsigned int *table; int length;
Currently, if the DT does not define num-interpolated-steps then num_steps is undefined and the interpolation code will deploy randomly. Fix with a simple initialize to zero. Fixes: 573fe6d1c25c ("backlight: pwm_bl: Linear interpolation between brightness-levels") Reported-by: Marcel Ziswiler <marcel.ziswiler@toradex.com> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Tested-by: Marcel Ziswiler <marcel.ziswiler@toradex.com> Reviewed-by: Douglas Anderson <dianders@chromium.org> Acked-by: Lee Jones <lee.jones@linaro.org> --- Notes: v4: - Remove line break from Fixes: and update the *-by:s v3: - Switch to the simplest fix and zero the uninitialized variable. git grep indicates that ~25% of calls to of_property_read_u32() use this pattern (pre-initialize optional properties with sane values and ignore the return code). v2: - Simplify SoB chain (with Marcel's permission) - Separate complex if statement and make other similar calls use same return code checking approach - Tidy up comment formatting and fix pre-existing grammar error drivers/video/backlight/pwm_bl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.17.1