drm/bridge: make bridge registration independent of drm flow

Currently, third party bridge drivers(ptn3460) are dependent
on the corresponding encoder driver init, since bridge driver
needs a drm_device pointer to finish drm initializations.
The encoder driver passes the drm_device pointer to the
bridge driver. Because of this dependency, third party drivers
like ptn3460 doesn't adhere to the driver model.

In this patch, we reframe the bridge registration framework
so that bridge initialization is split into 2 steps, and
bridge registration happens independent of drm flow:
--Step 1: gather all the bridge settings independent of drm and
	  add the bridge onto a global list of bridges.
--Step 2: when the encoder driver is probed, call drm_bridge_attach
	  for the corresponding bridge so that the bridge receives
	  drm_device pointer and continues with connector and other
	  drm initializations.

The old set of bridge helpers are removed, and a set of new helpers
are added to accomplish the 2 step initialization.

The bridge devices register themselves onto global list of bridges
when they get probed by calling "drm_bridge_add".

The parent encoder driver waits till the bridge is available
in the lookup table(by calling "of_drm_find_bridge") and then
continues with its initialization.

The encoder driver should also call "drm_bridge_attach" to pass
on the drm_device to the bridge object.

drm_bridge_attach inturn calls "bridge->funcs->attach" so that
bridge can continue with drm related initializations.

Signed-off-by: Ajay Kumar <ajaykumar.rs@samsung.com>
Acked-by: Inki Dae <inki.dae@samsung.com>
Tested-by: Rahul Sharma <rahul.sharma@samsung.com>
Tested-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Tested-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Tested-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Signed-off-by: Thierry Reding <treding@nvidia.com>

1 files changed, 0 insertions, 67 deletions

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 7936c5c2314c..0e4ec700b0a6 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -1066,58 +1066,6 @@ void drm_connector_unplug_all(struct drm_device *dev)
 EXPORT_SYMBOL(drm_connector_unplug_all);
 
 /**
- * drm_bridge_init - initialize a drm transcoder/bridge
- * @dev: drm device
- * @bridge: transcoder/bridge to set up
- *
- * Initialises a preallocated bridge. Bridges should be
- * subclassed as part of driver connector objects.
- *
- * Returns:
- * Zero on success, error code on failure.
- */
-int drm_bridge_init(struct drm_device *dev, struct drm_bridge *bridge)
-{
-	int ret;
-
-	drm_modeset_lock_all(dev);
-
-	ret = drm_mode_object_get(dev, &bridge->base, DRM_MODE_OBJECT_BRIDGE);
-	if (ret)
-		goto out;
-
-	bridge->dev = dev;
-
-	list_add_tail(&bridge->head, &dev->mode_config.bridge_list);
-	dev->mode_config.num_bridge++;
-
- out:
-	drm_modeset_unlock_all(dev);
-	return ret;
-}
-EXPORT_SYMBOL(drm_bridge_init);
-
-/**
- * drm_bridge_cleanup - cleans up an initialised bridge
- * @bridge: bridge to cleanup
- *
- * Cleans up the bridge but doesn't free the object.
- */
-void drm_bridge_cleanup(struct drm_bridge *bridge)
-{
-	struct drm_device *dev = bridge->dev;
-
-	drm_modeset_lock_all(dev);
-	drm_mode_object_put(dev, &bridge->base);
-	list_del(&bridge->head);
-	dev->mode_config.num_bridge--;
-	drm_modeset_unlock_all(dev);
-
-	memset(bridge, 0, sizeof(*bridge));
-}
-EXPORT_SYMBOL(drm_bridge_cleanup);
-
-/**
  * drm_encoder_init - Init a preallocated encoder
  * @dev: drm device
  * @encoder: the encoder to init
@@ -1712,7 +1660,6 @@ static int drm_mode_group_init(struct drm_device *dev, struct drm_mode_group *gr
 	total_objects += dev->mode_config.num_crtc;
 	total_objects += dev->mode_config.num_connector;
 	total_objects += dev->mode_config.num_encoder;
-	total_objects += dev->mode_config.num_bridge;
 
 	group->id_list = kcalloc(total_objects, sizeof(uint32_t), GFP_KERNEL);
 	if (!group->id_list)
@@ -1721,7 +1668,6 @@ static int drm_mode_group_init(struct drm_device *dev, struct drm_mode_group *gr
 	group->num_crtcs = 0;
 	group->num_connectors = 0;
 	group->num_encoders = 0;
-	group->num_bridges = 0;
 	return 0;
 }
 
@@ -1741,7 +1687,6 @@ int drm_mode_group_init_legacy_group(struct drm_device *dev,
 	struct drm_crtc *crtc;
 	struct drm_encoder *encoder;
 	struct drm_connector *connector;
-	struct drm_bridge *bridge;
 	int ret;
 
 	ret = drm_mode_group_init(dev, group);
@@ -1759,11 +1704,6 @@ int drm_mode_group_init_legacy_group(struct drm_device *dev,
 		group->id_list[group->num_crtcs + group->num_encoders +
 			       group->num_connectors++] = connector->base.id;
 
-	list_for_each_entry(bridge, &dev->mode_config.bridge_list, head)
-		group->id_list[group->num_crtcs + group->num_encoders +
-			       group->num_connectors + group->num_bridges++] =
-					bridge->base.id;
-
 	return 0;
 }
 EXPORT_SYMBOL(drm_mode_group_init_legacy_group);
@@ -5440,7 +5380,6 @@ void drm_mode_config_init(struct drm_device *dev)
 	INIT_LIST_HEAD(&dev->mode_config.fb_list);
 	INIT_LIST_HEAD(&dev->mode_config.crtc_list);
 	INIT_LIST_HEAD(&dev->mode_config.connector_list);
-	INIT_LIST_HEAD(&dev->mode_config.bridge_list);
 	INIT_LIST_HEAD(&dev->mode_config.encoder_list);
 	INIT_LIST_HEAD(&dev->mode_config.property_list);
 	INIT_LIST_HEAD(&dev->mode_config.property_blob_list);
@@ -5480,7 +5419,6 @@ void drm_mode_config_cleanup(struct drm_device *dev)
 	struct drm_connector *connector, *ot;
 	struct drm_crtc *crtc, *ct;
 	struct drm_encoder *encoder, *enct;
-	struct drm_bridge *bridge, *brt;
 	struct drm_framebuffer *fb, *fbt;
 	struct drm_property *property, *pt;
 	struct drm_property_blob *blob, *bt;
@@ -5491,11 +5429,6 @@ void drm_mode_config_cleanup(struct drm_device *dev)
 		encoder->funcs->destroy(encoder);
 	}
 
-	list_for_each_entry_safe(bridge, brt,
-				 &dev->mode_config.bridge_list, head) {
-		bridge->funcs->destroy(bridge);
-	}
-
 	list_for_each_entry_safe(connector, ot,
 				 &dev->mode_config.connector_list, head) {
 		connector->funcs->destroy(connector);