Op 29-03-17 om 16:06 schreef Daniel Vetter: > On Wed, Mar 29, 2017 at 03:51:08PM +0200, Maarten Lankhorst wrote: >> Op 29-03-17 om 15:31 schreef Boris Brezillon: >>> On Wed, 29 Mar 2017 15:26:45 +0200 >>> Daniel Vetter <daniel@xxxxxxxx> wrote: >>> >>>> On Wed, Mar 29, 2017 at 12:16:50PM +0200, Maarten Lankhorst wrote: >>>>> mode_valid() and get_modes() called >>>>> from drm_helper_probe_single_connector_modes() >>>>> may need to look at connector->state because what a valid mode is may >>>>> depend on connector properties being set. For example some HDMI modes >>>>> might be rejected when a connector property forces the connector >>>>> into DVI mode. >>>>> >>>>> Some implementations of detect() already lock all state, >>>>> so we have to pass an acquire_ctx to them to prevent a deadlock. >>>>> >>>>> This means changing the function signature of detect() slightly, >>>>> and passing the acquire_ctx for locking multiple crtc's. >>>>> It might be NULL, in which case expensive operations should be avoided. >>>>> >>>>> intel_dp.c however ignores the force flag, so still lock >>>>> connection_mutex there if needed. >>>>> >>>>> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> >>>>> Cc: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx> >>>>> Cc: Manasi Navare <manasi.d.navare@xxxxxxxxx> >>>> Hm only noticed this now, but mixing up force with the acquire_ctx sounds >>>> like very bad interface design. Yes, the only user of the new hook works >>>> like that, but that's really accidental I think. I think just having the >>>> ctx everywhere (for atomic drivers at least) would be a lot safer. This is >>>> extremely surprising (and undocumented suprise at that). >>> Yes, I was about to say the same thing: the interface is not very >>> clear, and I don't understand why ctx = NULL implies force = false. >> They're the same thing I fear. I could perhaps call it force_ctx instead, >> but non-zero ctx implies force, and other way around. Though I guess we could >> relax it, and have force = true imply ctx, but not the other way around. >> >> Would that be ok? > Why can't we supply a ctx always? I didn't see any reason not to in the > code ... > -Daniel Then drm_helper_hpd_irq_event and intel_hpd_irq_event have to do -EDEADLK handling too, it could be done but nothing would return -EDEADLK so it's unused code. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
