This is a note to let you know that I've just added the patch titled
drm/connector: Add support for out-of-band hotplug notification (v3)
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-connector-add-support-for-out-of-band-hotplug-no.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit c05bb8f58c3106f103cfa2802681dda339e876f3
Author: Hans de Goede <hdegoede@xxxxxxxxxx>
Date: Tue Aug 17 23:51:57 2021 +0200
drm/connector: Add support for out-of-band hotplug notification (v3)
[ Upstream commit 72ad49682dde3d9de5708b8699dc8e0b44962322 ]
Add a new drm_connector_oob_hotplug_event() function and
oob_hotplug_event drm_connector_funcs member.
On some hardware a hotplug event notification may come from outside the
display driver / device. An example of this is some USB Type-C setups
where the hardware muxes the DisplayPort data and aux-lines but does
not pass the altmode HPD status bit to the GPU's DP HPD pin.
In cases like this the new drm_connector_oob_hotplug_event() function can
be used to report these out-of-band events.
Changes in v2:
- Make drm_connector_oob_hotplug_event() take a fwnode as argument and
have it call drm_connector_find_by_fwnode() internally. This allows
making drm_connector_find_by_fwnode() a drm-internal function and
avoids code outside the drm subsystem potentially holding on the
a drm_connector reference for a longer period.
Changes in v3:
- Drop the data argument to the drm_connector_oob_hotplug_event
function since it is not used atm. This can be re-added later when
a use for it actually arises.
Tested-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Reviewed-by: Lyude Paul <lyude@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210817215201.795062-5-hdegoede@xxxxxxxxxx
Stable-dep-of: 89434b069e46 ("usb: typec: altmodes/displayport: Signal hpd low when exiting mode")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index fc06f73acd3c9..c4ed4f1b369c1 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -2514,6 +2514,33 @@ struct drm_connector *drm_connector_find_by_fwnode(struct fwnode_handle *fwnode)
return found;
}
+/**
+ * drm_connector_oob_hotplug_event - Report out-of-band hotplug event to connector
+ * @connector: connector to report the event on
+ *
+ * On some hardware a hotplug event notification may come from outside the display
+ * driver / device. An example of this is some USB Type-C setups where the hardware
+ * muxes the DisplayPort data and aux-lines but does not pass the altmode HPD
+ * status bit to the GPU's DP HPD pin.
+ *
+ * This function can be used to report these out-of-band events after obtaining
+ * a drm_connector reference through calling drm_connector_find_by_fwnode().
+ */
+void drm_connector_oob_hotplug_event(struct fwnode_handle *connector_fwnode)
+{
+ struct drm_connector *connector;
+
+ connector = drm_connector_find_by_fwnode(connector_fwnode);
+ if (IS_ERR(connector))
+ return;
+
+ if (connector->funcs->oob_hotplug_event)
+ connector->funcs->oob_hotplug_event(connector);
+
+ drm_connector_put(connector);
+}
+EXPORT_SYMBOL(drm_connector_oob_hotplug_event);
+
/**
* DOC: Tile group
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index d6c7554f1d405..03d39532c7080 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -1030,6 +1030,14 @@ struct drm_connector_funcs {
*/
void (*atomic_print_state)(struct drm_printer *p,
const struct drm_connector_state *state);
+
+ /**
+ * @oob_hotplug_event:
+ *
+ * This will get called when a hotplug-event for a drm-connector
+ * has been received from a source outside the display driver / device.
+ */
+ void (*oob_hotplug_event)(struct drm_connector *connector);
};
/**
@@ -1612,6 +1620,7 @@ drm_connector_is_unregistered(struct drm_connector *connector)
DRM_CONNECTOR_UNREGISTERED;
}
+void drm_connector_oob_hotplug_event(struct fwnode_handle *connector_fwnode);
const char *drm_get_connector_type_name(unsigned int connector_type);
const char *drm_get_connector_status_name(enum drm_connector_status status);
const char *drm_get_subpixel_order_name(enum subpixel_order order);
