On Sun, 18 Oct 2015 19:16:42 +0200, Russell King - ARM Linux wrote: > > On Sun, Oct 18, 2015 at 09:43:29PM +0530, Vinod Koul wrote: > > Right but can I ask why you didn't try making video as component and then > > CEC, audio and others receive the notification over this. > > Okay, I think I see what you're getting at. No, I don't want to tie > this stuff into the component helpers because that's the wrong approach. > > The component helper is purely about combining several struct devices > into one larger component for a subsystem which deals with card-level > components. It's not about cross-subsystem stuff. > > The problem with using it for cross-subsystem stuff is that it becomes > too tightly bound together: why should the graphics side get torn down > if you unload the audio or CEC driver? > > Audio and CEC are rather optional for HDMI - HDMI can work without audio > and CEC being present. However, audio can't be conveyed across the link > without the video side being configured. So, it makes sense to allow > the CEC and audio parts to be loaded separately (possibly as modules) > while having the video parts built-in to the kernel - especially if you > want to use the HDMI output as the console. > > Binding CEC and audio into the component helper alongside the video part > will mean that nothing will come up until all the components are present, > and everything will be torn down when any one of those components are > removed. Clearly, that's undesirable. Currently i915/audio component works as you described. The audio is optional and HDMI graphics works without audio, while HDMI HD-audio mandates i915 graphics. Takashi _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
