On Wed, Feb 8, 2017 at 1:45 AM, Mark yao <mark.yao@xxxxxxxxxxxxxx> wrote: > On 2017年02月08日 00:14, Sean Paul wrote: >> >> On Sun, Feb 05, 2017 at 03:36:36PM +0800, Mark Yao wrote: >>> >>> drm crtc already has mode_fixup callback to can do mode check, but >>> We actually want to valid display mode on connector getmode time, >>> mode_fixup can't do it. >>> >>> So add a private mode_valid callback to rockchip crtc, connectors can >>> check mode with this mode_valid callback. >>> >> There are some nasty layer violations happening in this set. You should >> use >> mode_fixup if the crtc has limitations on the mode being set. >> >> Sean > > Mode_fixup can also check crtc limitations, but it's secondly time to check > display mode. > > mode_fixup only works on drm_setcrtc or atomic_commit check, when userspace > get a series of display modes, > They don't know which display mode is bad before drm_setcrtc or > atomic_commit check, they need try, > but drm_setcrtc or atomic_commit check not only for display mode check, > means that userspace didn't have a sure > method to verify display mode. > > So I try to add the mode_valid callback to connector getmodes time, verify > display mode before send mode list to userspace. > then userspace would get a good display mode list. You need both, the kerneldoc of these hooks explains in detail why. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
