Quick question; if I want to validate a mode given to me by a connector/encoder as workable or not before I am going through the code to actually set that mode, how would I do this?

I expected to see a mode_valid callback in crtc or somewhere similar. What I've got right now is a drm connector and encoder, which are describing a silicon image hdmi transmitter, and an embedded crtc connected to it. While the transmitter is fairly capable the crtc in the SoC is not (it has a maximum pixel clock limitation of 133MHz which means I have to kill off modes above that like 1080p@60. There are other things I may need to limit too).

How do I coordinate such things from the drm_driver or crtc level up to the connector/encoder without making the connector/encoder intimately knowledgeable about the underlying crtc? Currently my only resort is to put the limits in platform data for the connector/encoder and use the mode_valid I already have to parse and discard modes which are plainly not going to be able to be clocked.