Re: [PATCH 1/2] video: exynos_dp: Add parsing of gpios pins to exynos-dp driver

[한진구 <jg1.han@samsung.com>]

Tuesday, May 14, 2013 11:17 PM, Vikas Sajjan wrote:
> 
> Hi Vikas,
> 
> On Tuesday 14 of May 2013 18:25:51 Vikas Sajjan wrote:
> >  Adds GPIO parsing functionality for "LCD backlight" and "LCD enable"
> >  GPIO pins of exynos dp controller.
> >
> > Signed-off-by: Vikas Sajjan <vikas.sajjan@linaro.org>
> > ---
> >  drivers/video/exynos/exynos_dp_core.c |   45
> > +++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+)
> >
> 
> I don't think that Exynos DP driver is right place for such code. Backlight
> and LCD drivers are responsible for backlight and LCD power control using
> backlight and LCD subsystems.
> 
> IMHO the correct solution would be to either extend existing backlight/lcd
> drivers found in drivers/video/backlight to support direct GPIO control and
> parse GPIO pins from device tree or create new gpio_bl and gpio_lcd drivers.

Hi Vikas Sajian,

I agree with Tomasz Figa's opinion.
Backlight/LCD framework should be used.
eDP panel backlight on SMDK5210 board can be controlled by PWM;
thus, pwm-backlight driver should be used.
Also, eDP panel reset pin should be controlled by using
platform-lcd driver.

> 
> CCing Richard, Florian and linux-fbdev.

Also, I have been doing backlight reviews instead of Richard,
please do CC'ing me.

Best regards,
Jingoo Han

> 
> Best regards,
> Tomasz