[PATCH v3 1/6] drm: bridge: Propagate the bus flags from bridge->timings

[Tomi Valkeinen]

On 30/11/2020 11:47, Laurent Pinchart wrote:

>>> Hasn't Boris commented in his review of v1 that bus flags should be set
>>> in atomic_check, even when they're static ? We're moving towards
>>> removing timings->input_bus_flags, so this patch goes in the wrong
>>> direction :-S
>>
>> We have atomic_check only if the bridge has implemented atomic funcs. And even if there's
>> atomic_check, not all bridges set the bus_flags there. So we need to either 1) fix the issue for now
>> as in this patch, or 2) convert all bridges to use atomic funcs and fix all the bridges to set the
>> bus_flags.
> 
> The second option is what we'd like to achieve. Wouldn't it be best to
> already start going in that direction ? We don't need to convert all
> bridge drivers in one go here, just the ones that are used by tidss.

I think that sounds fine, except that this is blocking the DisplayPort support for J7. We have
everything in for DP except dts changes (can be added only when the drivers work), and the connector
stuff.

The connector stuff includes this series (so that tidss supports the new connector model), and
"[PATCH RESEND v3 0/2] drm: add DisplayPort connector", which adds the connector driver.

The bridges currently used (that I know of) with tidss are cdns-mhdp, tfp410 and sii9022. I don't
expect converting those would be a huge job, but I'd still really like to get the DP working in
upstream without starting to expand the scope of the patches we need to enable it.

That said, we missed 5.11 so perhaps we have the time.

 Tomi

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