[PATCH] [rfc] drm/mst: split connector registration into two parts

[Dave Airlie]

From: Dave Airlie <airlied at redhat.com>

In order to cache the EDID properly for tiled displays, we
need to retrieve it before we register the connector with
userspace, otherwise userspace can call get resources
and try and get the edid before we've even cached it.

This fixes some problems when hotplugging mst monitors,
with X/mutter running.

Signed-off-by: Dave Airlie <airlied at redhat.com>
---
 drivers/gpu/drm/drm_dp_mst_topology.c  |  1 +
 drivers/gpu/drm/i915/intel_dp_mst.c    |  9 ++++++++-
 drivers/gpu/drm/radeon/radeon_dp_mst.c | 10 +++++++++-
 include/drm/drm_dp_mst_helper.h        |  1 +
 4 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index f6acb57..1b0ca1f 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -1129,6 +1129,7 @@ static void drm_dp_add_port(struct drm_dp_mst_branch *mstb,
 		if (port->port_num >= 8) {
 			port->cached_edid = drm_get_edid(port->connector, &port->aux.ddc);
 		}
+		(*mstb->mgr->cbs->register_connector)(port->connector);
 	}
 
 out:
diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c b/drivers/gpu/drm/i915/intel_dp_mst.c
index 3e4be5a..6ade068 100644
--- a/drivers/gpu/drm/i915/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/intel_dp_mst.c
@@ -462,11 +462,17 @@ static struct drm_connector *intel_dp_add_mst_connector(struct drm_dp_mst_topolo
 	drm_object_attach_property(&connector->base, dev->mode_config.tile_property, 0);
 
 	drm_mode_connector_set_path_property(connector, pathprop);
+	return connector;
+}
+
+static void intel_dp_register_mst_connector(struct drm_connector *connector)
+{
+	struct intel_connector *intel_connector = to_intel_connector(connector);
+	struct drm_device *dev = connector->dev;
 	drm_modeset_lock_all(dev);
 	intel_connector_add_to_fbdev(intel_connector);
 	drm_modeset_unlock_all(dev);
 	drm_connector_register(&intel_connector->base);
-	return connector;
 }
 
 static void intel_dp_destroy_mst_connector(struct drm_dp_mst_topology_mgr *mgr,
@@ -512,6 +518,7 @@ static void intel_dp_mst_hotplug(struct drm_dp_mst_topology_mgr *mgr)
 
 static struct drm_dp_mst_topology_cbs mst_cbs = {
 	.add_connector = intel_dp_add_mst_connector,
+	.register_connector = intel_dp_register_mst_connector,
 	.destroy_connector = intel_dp_destroy_mst_connector,
 	.hotplug = intel_dp_mst_hotplug,
 };
diff --git a/drivers/gpu/drm/radeon/radeon_dp_mst.c b/drivers/gpu/drm/radeon/radeon_dp_mst.c
index 5e09c06..9a9193b 100644
--- a/drivers/gpu/drm/radeon/radeon_dp_mst.c
+++ b/drivers/gpu/drm/radeon/radeon_dp_mst.c
@@ -286,12 +286,19 @@ static struct drm_connector *radeon_dp_add_mst_connector(struct drm_dp_mst_topol
 	drm_object_attach_property(&connector->base, dev->mode_config.path_property, 0);
 	drm_mode_connector_set_path_property(connector, pathprop);
 
+	return connector;
+}
+
+static void radeon_dp_register_mst_connector(struct drm_connector *connector)
+{
+	struct drm_device *dev = connector->dev;
+	struct radeon_device *rdev = dev->dev_private;
+
 	drm_modeset_lock_all(dev);
 	radeon_fb_add_connector(rdev, connector);
 	drm_modeset_unlock_all(dev);
 
 	drm_connector_register(connector);
-	return connector;
 }
 
 static void radeon_dp_destroy_mst_connector(struct drm_dp_mst_topology_mgr *mgr,
@@ -324,6 +331,7 @@ static void radeon_dp_mst_hotplug(struct drm_dp_mst_topology_mgr *mgr)
 
 struct drm_dp_mst_topology_cbs mst_cbs = {
 	.add_connector = radeon_dp_add_mst_connector,
+	.register_connector = radeon_dp_register_mst_connector,
 	.destroy_connector = radeon_dp_destroy_mst_connector,
 	.hotplug = radeon_dp_mst_hotplug,
 };
diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h
index 86d0b25..0f408b0 100644
--- a/include/drm/drm_dp_mst_helper.h
+++ b/include/drm/drm_dp_mst_helper.h
@@ -374,6 +374,7 @@ struct drm_dp_mst_topology_mgr;
 struct drm_dp_mst_topology_cbs {
 	/* create a connector for a port */
 	struct drm_connector *(*add_connector)(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, const char *path);
+	void (*register_connector)(struct drm_connector *connector);
 	void (*destroy_connector)(struct drm_dp_mst_topology_mgr *mgr,
 				  struct drm_connector *connector);
 	void (*hotplug)(struct drm_dp_mst_topology_mgr *mgr);
-- 
2.5.0