[PATCH] drm: Pass down CONNECTOR ID for user-space to use

[Marius Vlad <marius.vlad@collabora.com>]

Manually setting/forcing the connector status in sysfs does not
propagate the CONNECTOR ID. For drivers that use polling, including
manually setting it up with sysfs this would similarly to the HDP IRQ
path which can pass it through drm_connector_helper_hpd_irq_event().

Signed-off-by: Marius Vlad <marius.vlad@collabora.com>
---
 drivers/gpu/drm/drm_probe_helper.c | 28 ++++++++++++++++++++++++++--
 drivers/gpu/drm/drm_sysfs.c        |  1 +
 include/drm/drm_connector.h        |  8 ++++++++
 3 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c
index 6b3541159c0f..b472bfb43c17 100644
--- a/drivers/gpu/drm/drm_probe_helper.c
+++ b/drivers/gpu/drm/drm_probe_helper.c
@@ -843,9 +843,33 @@ static void output_poll_execute(struct work_struct *work)
 	mutex_unlock(&dev->mode_config.mutex);
 
 out:
-	if (changed)
-		drm_kms_helper_hotplug_event(dev);
+	if (changed) {
+		struct drm_connector *first_changed_connector = NULL;
+		if (!mutex_trylock(&dev->mode_config.mutex)) {
+			repoll = true;
+			goto repoll;
+		}
 
+		drm_connector_list_iter_begin(dev, &conn_iter);
+		drm_for_each_connector_iter(connector, &conn_iter) {
+			if (connector->sysfs_hotplug) {
+				drm_connector_get(connector);
+				first_changed_connector = connector;
+				connector->sysfs_hotplug = false;
+				break;
+			}
+		}
+		drm_connector_list_iter_end(&conn_iter);
+		mutex_unlock(&dev->mode_config.mutex);
+
+		if (first_changed_connector) {
+			drm_sysfs_connector_hotplug_event(connector);
+			drm_connector_put(first_changed_connector);
+		} else {
+			drm_kms_helper_hotplug_event(dev);
+		}
+	}
+repoll:
 	if (repoll)
 		schedule_delayed_work(delayed_work, DRM_OUTPUT_POLL_PERIOD);
 }
diff --git a/drivers/gpu/drm/drm_sysfs.c b/drivers/gpu/drm/drm_sysfs.c
index 60c1f26edb6f..c38b7a2accee 100644
--- a/drivers/gpu/drm/drm_sysfs.c
+++ b/drivers/gpu/drm/drm_sysfs.c
@@ -196,6 +196,7 @@ static ssize_t status_store(struct device *device,
 		return ret;
 
 	old_force = connector->force;
+	connector->sysfs_hotplug = true;
 
 	if (sysfs_streq(buf, "detect"))
 		connector->force = 0;
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index 137773dd138e..7a8344814219 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -2125,6 +2125,14 @@ struct drm_connector {
 	 */
 	uint8_t polled;
 
+	/**
+	 * @sysfs_hotplug:
+	 *
+	 * Set in by sysfs connector status to propagate CONNECTOR_ID to udev
+	 * and further down the stack.
+	 */
+	bool sysfs_hotplug;
+
 	/**
 	 * @dpms: Current dpms state. For legacy drivers the
 	 * &drm_connector_funcs.dpms callback must update this. For atomic
-- 
2.47.2