drm_connector_helper_funcs.detect_ctx() is expected to propagate
-EDEADLK so that context owners, e.g. drm_helper_probe_detect_ctx(), can
perform the required backoff and retry.

vc4_hdmi_handle_hotplug() instead runs its own retry loop and calls
drm_modeset_backoff() on an acquire context it does not own.  This drops
all locks in the context, including connection_mutex held by the core.

Drop the local retry logic and propagate -EDEADLK to the caller instead.
This aligns VC4 with the expected detect_ctx() semantics.

Signed-off-by: Cristian Ciocaltea <[email protected]>
---
 drivers/gpu/drm/vc4/vc4_hdmi.c | 23 +++++++----------------
 1 file changed, 7 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index ba16e7944cf3..72042fad04c5 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -344,12 +344,11 @@ static int vc4_hdmi_reset_link(struct drm_connector 
*connector,
        return drm_atomic_helper_reset_crtc(crtc, ctx);
 }
 
-static void vc4_hdmi_handle_hotplug(struct vc4_hdmi *vc4_hdmi,
-                                   struct drm_modeset_acquire_ctx *ctx,
-                                   enum drm_connector_status status)
+static int vc4_hdmi_handle_hotplug(struct vc4_hdmi *vc4_hdmi,
+                                  struct drm_modeset_acquire_ctx *ctx,
+                                  enum drm_connector_status status)
 {
        struct drm_connector *connector = &vc4_hdmi->connector;
-       int ret;
 
        /*
         * NOTE: This function should really be called with vc4_hdmi->mutex
@@ -368,17 +367,9 @@ static void vc4_hdmi_handle_hotplug(struct vc4_hdmi 
*vc4_hdmi,
        drm_atomic_helper_connector_hdmi_hotplug(connector, ctx, status);
 
        if (status != connector_status_connected)
-               return;
+               return 0;
 
-       for (;;) {
-               ret = vc4_hdmi_reset_link(connector, ctx);
-               if (ret == -EDEADLK) {
-                       drm_modeset_backoff(ctx);
-                       continue;
-               }
-
-               break;
-       }
+       return vc4_hdmi_reset_link(connector, ctx);
 }
 
 static int vc4_hdmi_connector_detect_ctx(struct drm_connector *connector,
@@ -416,10 +407,10 @@ static int vc4_hdmi_connector_detect_ctx(struct 
drm_connector *connector,
                        status = connector_status_connected;
        }
 
-       vc4_hdmi_handle_hotplug(vc4_hdmi, ctx, status);
+       ret = vc4_hdmi_handle_hotplug(vc4_hdmi, ctx, status);
        pm_runtime_put(&vc4_hdmi->pdev->dev);
 
-       return status;
+       return ret == -EDEADLK ? ret : status;
 }
 
 static int vc4_hdmi_connector_get_modes(struct drm_connector *connector)

-- 
2.55.0

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