[ADV7393] DRM Encoder Slave or DRM Bridge

[Vikas Patil]

On Wed, Sep 14, 2016 at 3:04 PM, Tomi Valkeinen <tomi.valkeinen at ti.com> wrote:
>
>
> On 13/09/16 16:13, Vikas Patil wrote:
>> Thanks Tomi for quick comment.
>>
>> I am thinking to base adv7393 driver on
>> "drivers\gpu\drm\omapdrm\displays\encoder-tc358768.c" as I don't think
>> any similar to adv7393 chip driver available. Could you please comment
>> if this will help to get adv chip running?
>
> I presume you're not using mainline kernel, as that driver is not there.
> I'm not familiar with adv7393, but yes, I think you can use that as an
> example.
>

Thanks a lot for your comments. I am using latest (i.e. 3.00.00.03 )
Processor SDK Linux Automotive which is based on linux 4.4.14.

As my display panel is connected as follows. I am little confused over
the values I need to set for following properties in probe function.

DPI1/VOUT1 -----16bit DRGB---> ADV7393 (Digital to Analog video
encoder) ------> CVBS Out ------> Display Panel


     dssdev->ops.dpi = &adv7393_dpi_ops; (atv?)
    dssdev->type = OMAP_DISPLAY_TYPE_DPI;
    dssdev->output_type = OMAP_DISPLAY_TYPE_DPI; (Do I need to use
OMAP_DISPLAY_TYPE_VENC, but DRA74x do not have VENC Encoder I think)
    dssdev->phy.dpi.data_lines = ddata->dpi_ndl;
    dssdev->port_num = 1;


As adv7393 takes 16-bit DRGB as input and gives composite as output,
does above configuration looks correct? or Do I need to change to
something else (e.g. dpi,sdi,dvi, hdmi, atv, dsi)?


>> I tried to add the device tree config but after adding device
>> configuration related to adv7393, my first display stopped working and
>> whenever I run kmscube or modetest it fails.
>
> If you don't have all the display pipelines working (i.e. the drivers
> present and working), none of the displays will work.
>
>> I have following configuration related to displays. Could anyone tell
>> me if I am doing anything wrong in DTS configuration? What could be
>> going wrong when I enable adv7393 related config so display 1 stops
>> working?
>
> The dts looks ok.
>
>  Tomi
>