Re: [RFC PATCH 4/4] video: display: Add Samsung s6e8ax0 display panel driver

[Tomasz Figa <t.figa@samsung.com>]

On Thursday 07 of February 2013 15:04:30 Vikas Sajjan wrote:
> Hi Figa,
> 
> On Wed, Jan 30, 2013 at 9:09 PM, Tomasz Figa <t.figa@samsung.com> wrote:
> > This patch adds Common Display Framework driver for Samsung s6e8ax0
> > MIPI DSI display panel.
> > 
> > Signed-off-by: Tomasz Figa <t.figa@samsung.com>
> > Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
> > ---
> > 
> >  drivers/video/display/Kconfig         |    3 +
> >  drivers/video/display/Makefile        |    1 +
> >  drivers/video/display/panel-s6e8ax0.c | 1027
> >  +++++++++++++++++++++++++++++++++ include/video/panel-s6e8ax0.h     
> >     |   41 ++
> >  4 files changed, 1072 insertions(+)
> >  create mode 100644 drivers/video/display/panel-s6e8ax0.c
> >  create mode 100644 include/video/panel-s6e8ax0.h
> > 
[snip]
> > +       lcd->ld = lcd_device_register("s6e8ax0", &pdev->dev, lcd,
> > +                       &s6e8ax0_lcd_ops);
> > +       if (IS_ERR(lcd->ld)) {
> > +               dev_err(&pdev->dev, "failed to register lcd ops.\n");
> > +               ret = PTR_ERR(lcd->ld);
> > +               goto err_lcd_register;
> > +       }
> > +
> > +       lcd->bd = backlight_device_register("s6e8ax0-bl", &pdev->dev,
> > lcd, +                       &s6e8ax0_backlight_ops, NULL);
> > +       if (IS_ERR(lcd->bd)) {
> > +               dev_err(&pdev->dev, "failed to register backlight
> > ops.\n"); +               ret = PTR_ERR(lcd->bd);
> > +               goto err_backlight_register;
> > +       }
> > +
> 
> I think we should try to remove the dependency with LCD framework and
> Backlight framework, and incorporate those functionality as par of
> CDF.
> you can refer to my similar patch "Make s6e8ax0 panel driver compliant
> with CDF" (
> http://comments.gmane.org/gmane.linux.drivers.video-input-infrastructur
> e/59187 ) which i had posted couple of weeks back, where I made an
> attempt to remove "lcd_ops" dependency.

Yes, I have written in the cover letter that those interfaces is just a 
hack to be able to control the display from userspace in current state of 
CDF.

I agree that CDF will have to be extended with backlight/brightness 
control. However currently CDF does not expose any interface to userspace.

Laurent, what's your opinion on this?

P.S. Tomasz is my first name.

Best regards,
-- 
Tomasz Figa
Samsung Poland R&D Center
SW Solution Development, Linux Platform