On Thu, Jul 30, 2015 at 5:32 PM, Theodore Ts'o <ty...@mit.edu> wrote: > On Thu, Jul 30, 2015 at 04:40:02PM +0200, Daniel Vetter wrote: >> On Wed, Jul 29, 2015 at 10:18:16PM -0700, Linus Torvalds wrote: >> > drivers/gpu/drm/drm_atomic_helper.c | 8 +++++--- >> > 1 file changed, 5 insertions(+), 3 deletions(-) >> > >> > diff --git a/drivers/gpu/drm/drm_atomic_helper.c >> > b/drivers/gpu/drm/drm_atomic_helper.c >> > index 5b59d5ad7d1c..aac212297b49 100644 >> > --- a/drivers/gpu/drm/drm_atomic_helper.c >> > +++ b/drivers/gpu/drm/drm_atomic_helper.c >> > @@ -230,10 +230,12 @@ update_connector_routing(struct drm_atomic_state >> > *state, int conn_idx) >> > } >> > >> > connector_state->best_encoder = new_encoder; >> > - idx = drm_crtc_index(connector_state->crtc); >> > + if (connector_state->crtc) { >> > + idx = drm_crtc_index(connector_state->crtc); >> > >> > - crtc_state = state->crtc_states[idx]; >> > - crtc_state->mode_changed = true; >> > + crtc_state = state->crtc_states[idx]; >> > + crtc_state->mode_changed = true; >> > + } >> >> This shouldn't happen since if it does we ended up stealing the encoder >> from the connector itself (we do check for connector_state->crtc earlier) >> and that would be a bug. I haven't figured out a precise theory but my >> guess is on the best_encoder selection, and indeed dp mst encoder >> selection seems to have gone belly up in 4.2 with the bisected commit. > > Well, I just tested Linus's patch and it works.
That's sersiously surprising if you mean display and everything actually works. Is dpms on/off and suspend and all that also still working? Can you please changed the check into a if (!connector_state->crtc) return 0; so that we don't blow up on the debug line below and then grab dmesg with drm.debug=0x1e when this happens? Note there will be lots of noise you might need to dig out full dmesg from logs. > BTW, is there any chance that I can suspend my laptop, and then move > it from my docking station at home (where I have a Dell 30" display) > to my docking station at work (where I have a Dell 24" display), and > actually have the new monitor be detected? For at least the past > year, I have to reboot in order to be able to use the external > monitor? This used to work, but it's been a very long-standing > regression. I undrstand that Multi-stream DP is a evil horrible hack, > and supporting it is painful, but this used to work, and it hasn't in > a long time. :-( Hm we seem to not reprobe mst state on resume. The quick hack below should help (but totally untested since still no dp mst hub here). -Daniel diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index 884b4f9b81c4..c0677c83a0e9 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -775,6 +775,9 @@ static int i915_drm_resume(struct drm_device *dev) /* Config may have changed between suspend and resume */ drm_helper_hpd_irq_event(dev); + dev_priv->short_hpd_port_mask = ~0; + queue_work(dev_priv->dp_wq, &dev_priv->dig_port_work); + intel_opregion_init(dev); intel_fbdev_set_suspend(dev, FBINFO_STATE_RUNNING, false); -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/