Re: [PATCHv2] backlight: pwm_bl: disable PWM when 'duty_cycle' is zero

From: Rob Herring
Date: Wed Jun 08 2016 - 16:06:51 EST


On Tue, Jun 07, 2016 at 12:13:49PM +0200, Lothar Waßmann wrote:
> 'brightness' is usually an index into a table of duty_cycle values,
> where the value at index 0 may well be non-zero
> (tegra30-apalis-eval.dts and tegra30-colibri-eval-v3.dts are real-life
> examples).
> Thus brightness == 0 does not necessarily mean that the PWM output
> will be inactive.
> Check for 'duty_cycle == 0' rather than 'brightness == 0' to decide
> whether to disable the PWM.
>
> Signed-off-by: Lothar Waßmann <LW@xxxxxxxxxxxxxxxxxxx>
> ---
> Changes wrt. v1:
> - update binding docs to reflect the change
>
> .../devicetree/bindings/leds/backlight/pwm-backlight.txt | 9 ++++++---
> drivers/video/backlight/pwm_bl.c | 4 ++--
> 2 files changed, 8 insertions(+), 5 deletions(-)

Acked-by: Rob Herring <robh@xxxxxxxxxx>