On 12/04/17 17:04, Hans Verkuil wrote: >> So is some other driver supporting this already? Or is the omap4 the >> first platform you're trying this on? > > No, there are quite a few CEC drivers by now, but typically the CEC block is > a totally independent IP block with its own power, irq, etc. The omap4 is by far > the most complex one to set up with various GPIO pins, interrupts, regulators, > etc. to deal with. > > Normally it takes about 2 days to make a new CEC driver, but the omap4 is much > more work :-( Ok. I mentioned the omapdrm restructuring that we've planned to do, I think after that this will be easier to implement in a nice way. For now, I think more or less what you have now is an acceptable solution. We can hack the tpd12s015 to keep the level shifter always enabled, and, afaics, everything else can be handled inside the hdmi4 driver, right? Generally speaking, what are the "dependencies" for CEC? It needs to access EDID? Does CEC care about HPD? Does it care if the cable is connected or not? For Panda, the level shifter of tpd12s015 is obviously one hard dendency. Is there anything else CEC needs to access or control (besides the CEC IP itself)? Tomi