On Wed, May 25, 2016 at 05:37:41PM +0800, Ying Liu wrote: > On Tue, May 24, 2016 at 6:57 PM, Daniel Vetter <daniel@xxxxxxxx> wrote: > > On Tue, May 24, 2016 at 06:10:44PM +0800, Liu Ying wrote: > >> Since CRTC has already been disabled in crtc_funcs->prepare(), it doesn't hurt > >> to disable the primary plane in drm_helper_crtc_mode_set() before enabling it > >> in drm_helper_crtc_mode_set_base(). This makes those who reject active plane > >> update in plane_funcs->atomic_check() happy. > > > > How/where exactly do you blow up? > >> > >> Signed-off-by: Liu Ying <gnuiyl@xxxxxxxxx> > >> --- > >> drivers/gpu/drm/drm_crtc_helper.c | 9 +++++++++ > >> 1 file changed, 9 insertions(+) > >> > >> diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c > >> index 79555d2..7fabcd7 100644 > >> --- a/drivers/gpu/drm/drm_crtc_helper.c > >> +++ b/drivers/gpu/drm/drm_crtc_helper.c > >> @@ -1013,6 +1013,15 @@ int drm_helper_crtc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mod > >> goto out; > >> } > >> > >> + /* > >> + * It doesn't hurt to disable primary plane here since crtc is off > >> + * and we'll enable it again in drm_helper_crtc_mode_set_base() > >> + * below soon. > >> + */ > >> + ret = drm_plane_helper_disable(crtc->primary); > > > > You can't call this helper from crtc helpers. drm_plane_helper_disable > > assumes that a) you've already extracted universal plane support for the > > primary plane by registering a proper drm_plane for it b) that you're > > driver is at least partially using atomic hooks already. > > > > Both assumptions are wrong for all current users of this function. > > drm_helper_crtc_mode_set() is purely a legacy helper for legecy drivers. > > Isn't the function a transitional helper, just as the kdoc claims? > It looks all current users are sort of atomic users already. drm_helper_crtc_mode_set is exclusively used by legacy drivers. drm_plane_helper_disable can be used for transitioning to atomic. Calling the latter from the former means you break every non-transition legacy driver. -Daniel > > Regards, > Liu Ying > > > -Daniel > > > >> + if (ret) > >> + goto out; > >> + > >> swap(crtc->state, crtc_state); > >> > >> crtc_funcs->mode_set_nofb(crtc); > >> -- > >> 2.7.4 > >> > >> _______________________________________________ > >> dri-devel mailing list > >> dri-devel@xxxxxxxxxxxxxxxxxxxxx > >> https://lists.freedesktop.org/mailman/listinfo/dri-devel > > > > -- > > Daniel Vetter > > Software Engineer, Intel Corporation > > http://blog.ffwll.ch -- 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
