[Intel-gfx] [PATCH v2 4/5] drm/i915: Don't change the status of forced connectors during hotplug detect

[Imre Deak]

DRM display connectors forced to a connected/disconnected state via the
drm_connector::force member shouldn't change their status. Atm, this can
still happen in the connector's detect function when called to handle a
hotplug event. This in turn may lead to the GETCONNECTOR ioctl to report
the incorrect state if it's called to return the connector properties
without doing an actual detection (by calling the ioctl with a non-zero
drm_mode_get_connector::count_modes).

Fix the above by updating the connector state during hotplug detect only
if the connector state is not forced.

Testcase: igt at kms_force_connector_basic@force-connector-state
Signed-off-by: Imre Deak <imre.deak at intel.com>
---
 drivers/gpu/drm/i915/display/intel_hotplug.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_hotplug.c b/drivers/gpu/drm/i915/display/intel_hotplug.c
index d9f0ab1d953b9..1f6fa3f994feb 100644
--- a/drivers/gpu/drm/i915/display/intel_hotplug.c
+++ b/drivers/gpu/drm/i915/display/intel_hotplug.c
@@ -267,14 +267,16 @@ intel_encoder_hotplug(struct intel_encoder *encoder,
 	struct drm_device *dev = connector->base.dev;
 	enum drm_connector_status old_status;
 	u64 old_epoch_counter;
+	int status;
 	bool ret = false;
 
 	drm_WARN_ON(dev, !mutex_is_locked(&dev->mode_config.mutex));
 	old_status = connector->base.status;
 	old_epoch_counter = connector->base.epoch_counter;
 
-	connector->base.status =
-		drm_helper_probe_detect(&connector->base, NULL, false);
+	status = drm_helper_probe_detect(&connector->base, NULL, false);
+	if (!connector->base.force)
+		connector->base.status = status;
 
 	if (old_epoch_counter != connector->base.epoch_counter)
 		ret = true;
-- 
2.37.2