[RFC PATCH 2/3] drm/msm: filter out modes for DSI bridge having unsupported clock

[Dmitry Baryshkov]

On 30/08/2022 06:33, Abhinav Kumar wrote:
> DSI interface used with a bridge chip connected to an external
> display is subject to the same pixel clock limits as one
> which is natively pluggable like DisplayPort.
> 
> Hence filter out DSI modes having an unsupported pixel clock
> if its connected to a bridge which is pluggable.
> 
> Ideally, this can be accommodated into msm_dsi_modeset_init()
> by passing an extra parameter but this will also affect non-dpu
> targets. Till we add the same logic for non-dpu chipsets, lets
> have this as a separate call.

I think this makes DP/DSI depend too much on the DPU and DPU internals. 
Can we instead use clk_round_rate() in the .mode_valid in DSI/DP/HDMI 
drivers in order to check that the requested rate can be achieved?

-- 
With best wishes
Dmitry