[PATCH V2 3/9] drm/panel: Add driver for exynos_dp based panels

[Ajay kumar]

Hi Thierry,


On Tue, Apr 22, 2014 at 1:56 PM, Thierry Reding
<thierry.reding at gmail.com> wrote:
> On Tue, Apr 22, 2014 at 04:09:12AM +0530, Ajay Kumar wrote:
>> This patch adds a simple driver to handle all the LCD and LED
>> powerup/down routines needed to support eDP/eDP-LVDS panels
>> supported on exynos boards.
>>
>> The LCD and LED units are usually powered up via regulators,
>> and almost on all boards, we will have a BL_EN pin to enable/
>> disable the backlight. Sometimes, we can have LCD_EN switches
>> as well. The routines in this driver can be used to control
>> panel power sequence on such boards.
>>
>> Signed-off-by: Ajay Kumar <ajaykumar.rs at samsung.com>
>> ---
>> Changes since V1:
>>       Added routine for post_disable, removed few unwanted headers.
>>       Refactored a lot of code.
>>
>>  .../devicetree/bindings/panel/exynos-dp-panel.txt  |   45 ++++
>>  drivers/gpu/drm/panel/Kconfig                      |    9 +
>>  drivers/gpu/drm/panel/Makefile                     |    1 +
>>  drivers/gpu/drm/panel/panel-exynos-dp.c            |  251 ++++++++++++++++++++
>>  4 files changed, 306 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/panel/exynos-dp-panel.txt
>>  create mode 100644 drivers/gpu/drm/panel/panel-exynos-dp.c
>
> What this patch does is in no way Exynos specific. It is also not eDP
> specific.
>
Right. This is not at all writing into any "exynos" specific register,
but can't this be just a placeholder for all the panel controls
which can serve boards which use exynos_dp?

> This conflates panel drivers with board drivers in a strange way. Panel
> drivers should be for *panels*, not for a given SoC or specific outputs
> on that SoC.
>
Right. But for that matter, even the "panel-simple" driver is doing the same,
which is just a placeholder for "generic" panel controls which serves
multiple boards.
I din't choose to reuse that because the boards which I have expect more
control over the panel sequence as mentioned before.
If you don't mind, I can fit in all these settings into panel-simple
driver itself ;)
But again, I should be able to register the panel driver much before
exynos_dp gets probed, That's the actual catch!


Thanks and regards,
Ajay Kumar