[PATCH 02/18] drm/bridge: Add HDMI output fmt helper

[Neil Armstrong]

On 18/03/2021 19:31, Jernej Škrabec wrote:
> Dne sreda, 17. marec 2021 ob 17:08:07 CET je Neil Armstrong napisal(a):
>> On 17/03/2021 16:43, Maxime Ripard wrote:
>>> The atomic_get_output_bus_fmts bridge callback is there to list the
>>> available formats for output by decreasing order of preference.
>>>
>>> On HDMI controllers, we have a fairly static list that will depend on
>>> what the HDMI sink is capable of and the BPC our controller can output.
>>>
>>> The dw-hdmi driver already has that code done in a fairly generic
>>> manner, so let's turn that code into an helper for all the HDMI
>>> controllers to reuse.
>>
>> This code was based on the capabilities of the DW-HDMI IP, copying it as-is
>> doesn't make much sense, we should be able to filter out formats the HDMI IP
>> doesn't support.
> 
> HDMI standard has pretty strict requirements which formats should be 
> supported, so cores should have very similar capabilities.

Yes for output formats (we still may need to filter out 420, 422 for example),

No for input formats, since it depends entirely on the capability of the transceiver
in terms of format conversion.

Neil

> 
> Best regards,
> Jernej
> 
>