Merge tag 'topic/drm-misc-2015-10-19' of git://anongit.freedesktop.org/drm-intel into drm-next

More drm-misc for 4.4.
- fb refcount fix in atomic fbdev
- various locking reworks to reduce drm_global_mutex and dev->struct_mutex
- rename docbook to gpu.tmpl and include vga_switcheroo stuff, plus more
  vga_switcheroo (Lukas Wunner)
- viewport check fixes for atomic drivers from Ville
- DRM_DEBUG_VBL from Ville
- non-contentious header fixes from Mikko Rapeli
- small things all over

* tag 'topic/drm-misc-2015-10-19' of git://anongit.freedesktop.org/drm-intel: (31 commits)
  drm/fb-helper: Fix fb refcounting in pan_display_atomic
  drm/fb-helper: Set plane rotation directly
  drm: fix mutex leak in drm_dp_get_mst_branch_device
  drm: Check plane src coordinates correctly during page flip for atomic drivers
  drm: Check crtc viewport correctly with rotated primary plane on atomic drivers
  drm: Refactor plane src coordinate checks
  drm: Swap w/h when converting the mode to src coordidates for a rotated primary plane
  drm: Don't leak fb when plane crtc coodinates are bad
  ALSA: hda - Spell vga_switcheroo consistently
  drm/gem: Use kref_get_unless_zero for the weak mmap references
  drm/vgem: Drop vgem_drm_gem_mmap
  drm: Fix return value of drm_framebuffer_init()
  drm/gem: Use container_of in drm_gem_object_free
  drm/gem: Check locking in drm_gem_object_unreference
  drm/gem: Drop struct_mutex requirement from drm_gem_mmap_obj
  drm/i810_drm.h: include drm/drm.h
  r128_drm.h: include drm/drm.h
  savage_drm.h: include <drm/drm.h>
  gpu/doc: Convert to markdown harder
  gpu/doc: Add vga_switcheroo documentation
  ...

1 files changed, 4 insertions, 3 deletions

diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index bf27a07dbce3..2d46fc6230c2 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -1194,17 +1194,18 @@ static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_
 
 		list_for_each_entry(port, &mstb->ports, next) {
 			if (port->port_num == port_num) {
-				if (!port->mstb) {
+				mstb = port->mstb;
+				if (!mstb) {
 					DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]);
-					return NULL;
+					goto out;
 				}
 
-				mstb = port->mstb;
 				break;
 			}
 		}
 	}
 	kref_get(&mstb->kref);
+out:
 	mutex_unlock(&mgr->lock);
 	return mstb;
 }