[PATCH v3] drm/probe_helper: warning on poll_enabled for issue catching

[Guchun Chen]

In order to catch issues in other drivers to ensure proper call
sequence of polling function.

v2: drop Fixes tag in commit message (Bert & Jani)
v3: use drm_WARN_ON instead of WARN_ON (Jani)

Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/2411
Reported-by: Bert Karwatzki <spasswolf at web.de>
Suggested-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
Signed-off-by: Guchun Chen <guchun.chen at amd.com>
---
 drivers/gpu/drm/drm_probe_helper.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c
index 8127be134c39..d812a4e91760 100644
--- a/drivers/gpu/drm/drm_probe_helper.c
+++ b/drivers/gpu/drm/drm_probe_helper.c
@@ -852,6 +852,8 @@ EXPORT_SYMBOL(drm_kms_helper_is_poll_worker);
  */
 void drm_kms_helper_poll_disable(struct drm_device *dev)
 {
+	drm_WARN_ON(dev, !dev->mode_config.poll_enabled);
+
 	if (dev->mode_config.poll_running)
 		drm_kms_helper_disable_hpd(dev);
 
-- 
2.25.1