[U-Boot] [PATCH 11/17] sunxi: video: Add support for VGA via external DACs connected to the LCD pins

[Chen-Yu Tsai]

Hi Hans,

On Tue, Dec 30, 2014 at 3:25 AM, Hans de Goede <hdegoede at redhat.com> wrote:
> Hi,
>
>
> On 29-12-14 14:51, Ian Campbell wrote:
>>
>> On Wed, 2014-12-24 at 20:06 +0100, Hans de Goede wrote:
>>>
>>> Add support for external DACs connected to the parallel LCD interface
>>> driving
>>> a VGA connector, such as found on the Olimex A13 boards.
>>>
>>> Signed-off-by: Hans de Goede <hdegoede at redhat.com>
>>
>>
>> Acked-by: Ian Campbell <ijc at hellion.org.uk>
>>
>>> ---
>>>   board/sunxi/Kconfig           |  9 +++++++++
>>>   drivers/video/sunxi_display.c | 14 ++++++++++++++
>>>   2 files changed, 23 insertions(+)
>>>
>>> diff --git a/board/sunxi/Kconfig b/board/sunxi/Kconfig
>>> index 7a8503b..3e42866 100644
>>> --- a/board/sunxi/Kconfig
>>> +++ b/board/sunxi/Kconfig
>>> @@ -253,6 +253,15 @@ config VIDEO_HDMI
>>>         ---help---
>>>         Say Y here to add support for outputting video over HDMI.
>>>
>>> +config VIDEO_VGA_VIA_LCD
>>> +       boolean "VGA via LCD controller support"
>>> +       depends on VIDEO
>>> +       default n
>>> +       ---help---
>>> +       Say Y here to add support for external DACs connected to the
>>> parallel
>>> +       LCD interface driving a VGA connector, such as found on the
>>> +       Olimex A13 boards.
>>
>>
>> But not unique to those boards I take it?
>
>
> Actually sofar it is unique to those boards, both the normal and the Micro
> variant (in theory we could see something similar on other boards one day).

The Hummingbird A31 has the same setup, using an external DAC for the
RGB signals, as it doesn't have the TV encoder. See:

    http://linux-sunxi.org/Merrii_Hummingbird_A31#VGA_out

ChenYu