The code for detecting and updating the connector status in cdn_dp_pd_event_work() has a number of problems.

- It does not aquire the locks to call the detect helper and update the connector status. These are struct drm_mode_config.connection_mutex and struct drm_mode_config.mutex.

- It does not use drm_helper_probe_detect(), which helps with the details of locking and detection.

- It uses the connector's status field to determine a change to the connector status. The epoch_counter field is the correct one. The field signals a change even if the connector status' value did not change.

Replace the code with a call to drm_connector_helper_hpd_irq_event(), which fixes all these problems.

Signed-off-by: Thomas Zimmermann tzimmermann@suse.de Fixes: 81632df69772 ("drm/rockchip: cdn-dp: do not use drm_helper_hpd_irq_event") Cc: Chris Zhong zyw@rock-chips.com Cc: Guenter Roeck groeck@chromium.org Cc: Sandy Huang hjc@rock-chips.com Cc: "Heiko Stübner" heiko@sntech.de Cc: Andy Yan andy.yan@rock-chips.com Cc: dri-devel@lists.freedesktop.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-rockchip@lists.infradead.org Cc: stable@vger.kernel.org # v4.11+ --- drivers/gpu/drm/rockchip/cdn-dp-core.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/rockchip/cdn-dp-core.c b/drivers/gpu/drm/rockchip/cdn-dp-core.c index b04538907f95..f576b1aa86d1 100644 --- a/drivers/gpu/drm/rockchip/cdn-dp-core.c +++ b/drivers/gpu/drm/rockchip/cdn-dp-core.c @@ -947,9 +947,6 @@ static void cdn_dp_pd_event_work(struct work_struct *work) { struct cdn_dp_device *dp = container_of(work, struct cdn_dp_device, event_work); - struct drm_connector *connector = &dp->connector; - enum drm_connector_status old_status; - int ret;

mutex_lock(&dp->lock); @@ -1009,11 +1006,7 @@ static void cdn_dp_pd_event_work(struct work_struct *work)

out: mutex_unlock(&dp->lock); - - old_status = connector->status; - connector->status = connector->funcs->detect(connector, false); - if (old_status != connector->status) - drm_kms_helper_hotplug_event(dp->drm_dev); + drm_connector_helper_hpd_irq_event(&dp->connector); }

static int cdn_dp_pd_event(struct notifier_block *nb,