On Tue, Feb 14, 2017 at 01:03:27PM -0800, John Stultz wrote: > On Tue, Feb 14, 2017 at 12:22 PM, Daniel Vetter <daniel@xxxxxxxx> wrote: > > On Tue, Feb 14, 2017 at 11:45:54AM -0800, John Stultz wrote: > >> > >> Not following here. What do you mean by "put it into drivers"? Where? > > > > In your driver callback for ->mode_valid, call into a shared function to > > validate CRTC limits. Which you also call from the crtc's ->mode_fixup > > function. > > So bascially have the adv7511 driver's mode_valid() have a special > callback to the kirin (and freedreno, and whatever other) drm driver > to check the modes? Or I guess the drm driver that uses that bridge > should register something w/ the adv7511 code? > > Part of my confusion here is that the main issue is that its not just > one driver I'm dealing with, and they're all really just tied together > via device tree, so I'm not sure how to special case it in just one of > the drivers. This sounds you want to fix this for bridges, but your patch only adds a crtc callback? > > In short my complain here is that this is only a partial solution of the > > larger problem, specific for your driver. That kind of code is better put > > into drivers, until we have a clear understanding to type up something > > complete in the helpers. Shared code is imo overrated :-) > > Yea, apologies for my not seeing the larger problem at first (its > still a bit hazy, really), part of this submission is just trying to > get something to throw darts at and figure out the right thing. > > But I'll try to figure out another approach here. Latest kerneldoc in drm-tip should explain this, not sure you didn't spot it or looked at an old kernel version. For drm docs, _always_ look at drm-tip, they're moving real fast :-) https://dri.freedesktop.org/docs/drm/gpu/drm-kms-helpers.html#modeset-helper-reference-for-common-vtables See e.g. drm_crtc_helpers_funcs->mode_fixup docs, it's there. There's explanations sprinkled at various places (mode_valid, plus the different helper funcs), probably good to first hunt these all down. Then read a bunch of driver callbacks so you have a better idea of the patterns of checks, otoh _lots_ of kms drivers get this wrong :( Cheers, Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
