On Mon, 10 Dec 2018, Enric Balletbo i Serra wrote:
> Commit '88ba95bedb79 ("backlight: pwm_bl: Compute brightness of LED
> linearly to human eye")' allows the possibility to compute a default
> brightness table when there isn't the brightness-levels property in the
> DT. Unfortunately the changes made broke the pwm backlight for the
> non-DT boards.
>
> Usually, the non-DT boards don't pass the brightness levels via platform
> data, instead, it sets the max_brightness in their platform data and the
> driver calculates the level without a table. The offending patch assumed
> that when there is no brightness levels table we should create one, but this
> is clearly wrong for the non-DT case.
>
> After this patch the code handles the DT and the non-DT case taking in
> consideration also if max_brightness is set or not.
>
> Fixes: 88ba95bedb79 ("backlight: pwm_bl: Compute brightness of LED linearly to human eye")
> Cc: <stable@xxxxxxxxxxxxxxx>
> Reported-by: Robert Jarzmik <robert.jarzmik@xxxxxxx>
> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx>
> Tested-by: Robert Jarzmik <robert.jarzmik@xxxxxxx>
> Acked-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx>
> ---
>
> Changes in v3:
> - Fixed some typos in commit message.
> - Removed ' in Fixes tag.
>
> Changes in v2:
> - Rebase on top of mainline
> - Add Tested-by and Acked-by tags.
>
> drivers/video/backlight/pwm_bl.c | 41 +++++++++++++++++++++++++++-----
> 1 file changed, 35 insertions(+), 6 deletions(-)
FYI, this patch is now in Mainline.
--
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
