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 [off-list ref] wrote:

quoted

This patch adds Common Display Framework driver for Samsung s6e8ax0
MIPI DSI display panel.

Signed-off-by: Tomasz Figa <redacted>
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]

quoted

+       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