From 3d3f7c1e68691574c1d87cd0f9f2348323bc0199 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Tue, 17 Aug 2021 23:51:56 +0200 Subject: drm/connector: Add drm_connector_find_by_fwnode() function (v3) Add a function to find a connector based on a fwnode. This will be used by the new drm_connector_oob_hotplug_event() function which is added by the next patch in this patch-set. Changes in v2: - Complete rewrite to use a global connector list in drm_connector.c rather then using a class-dev-iter in drm_sysfs.c Changes in v3: - Add forward declaration for struct fwnode_handle to drm_crtc_internal.h (fixes warning reported by kernel test robot ) Tested-by: Heikki Krogerus Signed-off-by: Hans de Goede Reviewed-by: Lyude Paul Link: https://lore.kernel.org/r/20210817215201.795062-4-hdegoede@redhat.com --- drivers/gpu/drm/drm_connector.c | 50 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) (limited to 'drivers/gpu/drm/drm_connector.c') diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c index 3ad359a216ff..7d72bcefa4d6 100644 --- a/drivers/gpu/drm/drm_connector.c +++ b/drivers/gpu/drm/drm_connector.c @@ -65,6 +65,14 @@ * support can instead use e.g. drm_helper_hpd_irq_event(). */ +/* + * Global connector list for drm_connector_find_by_fwnode(). + * Note drm_connector_[un]register() first take connector->lock and then + * take the connector_list_lock. + */ +static DEFINE_MUTEX(connector_list_lock); +static LIST_HEAD(connector_list); + struct drm_conn_prop_enum_list { int type; const char *name; @@ -267,6 +275,7 @@ int drm_connector_init(struct drm_device *dev, goto out_put_type_id; } + INIT_LIST_HEAD(&connector->global_connector_list_entry); INIT_LIST_HEAD(&connector->probed_modes); INIT_LIST_HEAD(&connector->modes); mutex_init(&connector->mutex); @@ -534,6 +543,9 @@ int drm_connector_register(struct drm_connector *connector) /* Let userspace know we have a new connector */ drm_sysfs_hotplug_event(connector->dev); + mutex_lock(&connector_list_lock); + list_add_tail(&connector->global_connector_list_entry, &connector_list); + mutex_unlock(&connector_list_lock); goto unlock; err_debugfs: @@ -562,6 +574,10 @@ void drm_connector_unregister(struct drm_connector *connector) return; } + mutex_lock(&connector_list_lock); + list_del_init(&connector->global_connector_list_entry); + mutex_unlock(&connector_list_lock); + if (connector->funcs->early_unregister) connector->funcs->early_unregister(connector); @@ -2545,6 +2561,40 @@ out: return ret; } +/** + * drm_connector_find_by_fwnode - Find a connector based on the associated fwnode + * @fwnode: fwnode for which to find the matching drm_connector + * + * This functions looks up a drm_connector based on its associated fwnode. When + * a connector is found a reference to the connector is returned. The caller must + * call drm_connector_put() to release this reference when it is done with the + * connector. + * + * Returns: A reference to the found connector or an ERR_PTR(). + */ +struct drm_connector *drm_connector_find_by_fwnode(struct fwnode_handle *fwnode) +{ + struct drm_connector *connector, *found = ERR_PTR(-ENODEV); + + if (!fwnode) + return ERR_PTR(-ENODEV); + + mutex_lock(&connector_list_lock); + + list_for_each_entry(connector, &connector_list, global_connector_list_entry) { + if (connector->fwnode == fwnode || + (connector->fwnode && connector->fwnode->secondary == fwnode)) { + drm_connector_get(connector); + found = connector; + break; + } + } + + mutex_unlock(&connector_list_lock); + + return found; +} + /** * DOC: Tile group -- cgit v1.2.3