Subject: [PATCH 24/37] drm/atomic: move drm_atomic_helper_disable_all() and drm_atomic_helper_shutdown() from drm_atomic_helper to drm_atomic

From: Luca Ceresoli <[email-masked]>
Date: Tue, 19 May 2026 12:37:41 +0200

To support the upcoming DRM bridge hotplug, the drm_bridge.c code will need
to call drm_atomic_helper_shutdown() to disable the pipeline when the tail
bridges of the pipeline are removed without tearing down the card.

However this would create a module dependency loop between the drm module
(where drm_encoder is) and the drm_kms_helper module where
drm_atomic_helper_shutdown() function currently is and which already
depends on the drm module.

Solve by moving drm_atomic_helper_shutdown(), along with its callee
drm_atomic_helper_disable_all(), to drm_atomic which is in the drm
module. Use identical names except for dropping the "_helper" infix, and
make the original functions a deprecated wrapper to the new ones.

No changes to the functions body.

No functional changes except for moving the code to a different module.

Signed-off-by: Luca Ceresoli <[email-masked]>
---
 drivers/gpu/drm/drm_atomic.c        | 115 ++++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/drm_atomic_helper.c |  76 ++----------------------
 include/drm/drm_atomic.h            |   3 +
 3 files changed, 124 insertions(+), 70 deletions(-)

diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 9b2009262c97..7d12c062c16d 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -1993,6 +1993,121 @@ int __drm_atomic_helper_set_config(struct drm_mode_set *set,
 }
 EXPORT_SYMBOL(__drm_atomic_helper_set_config);
 
+/**
+ * drm_atomic_disable_all - disable all currently active outputs
+ * @dev: DRM device
+ * @ctx: lock acquisition context
+ *
+ * Loops through all connectors, finding those that aren't turned off and then
+ * turns them off by setting their DPMS mode to OFF and deactivating the CRTC
+ * that they are connected to.
+ *
+ * This is used for example in suspend/resume to disable all currently active
+ * functions when suspending. If you just want to shut down everything at e.g.
+ * driver unload, look at drm_atomic_helper_shutdown().
+ *
+ * Note that if callers haven't already acquired all modeset locks this might
+ * return -EDEADLK, which must be handled by calling drm_modeset_backoff().
+ *
+ * Returns:
+ * 0 on success or a negative error code on failure.
+ *
+ * See also:
+ * drm_atomic_helper_suspend(), drm_atomic_helper_resume() and
+ * drm_atomic_helper_shutdown().
+ */
+int drm_atomic_disable_all(struct drm_device *dev,
+			   struct drm_modeset_acquire_ctx *ctx)
+{
+	struct drm_atomic_commit *state;
+	struct drm_connector_state *conn_state;
+	struct drm_connector *conn;
+	struct drm_plane_state *plane_state;
+	struct drm_plane *plane;
+	struct drm_crtc_state *crtc_state;
+	struct drm_crtc *crtc;
+	int ret, i;
+
+	state = drm_atomic_commit_alloc(dev);
+	if (!state)
+		return -ENOMEM;
+
+	state->acquire_ctx = ctx;
+
+	drm_for_each_crtc(crtc, dev) {
+		crtc_state = drm_atomic_get_crtc_state(state, crtc);
+		if (IS_ERR(crtc_state)) {
+			ret = PTR_ERR(crtc_state);
+			goto free;
+		}
+
+		crtc_state->active = false;
+
+		ret = drm_atomic_set_mode_prop_for_crtc(crtc_state, NULL);
+		if (ret < 0)
+			goto free;
+
+		ret = drm_atomic_add_affected_planes(state, crtc);
+		if (ret < 0)
+			goto free;
+
+		ret = drm_atomic_add_affected_connectors(state, crtc);
+		if (ret < 0)
+			goto free;
+	}
+
+	for_each_new_connector_in_state(state, conn, conn_state, i) {
+		ret = drm_atomic_set_crtc_for_connector(conn_state, NULL);
+		if (ret < 0)
+			goto free;
+	}
+
+	for_each_new_plane_in_state(state, plane, plane_state, i) {
+		ret = drm_atomic_set_crtc_for_plane(plane_state, NULL);
+		if (ret < 0)
+			goto free;
+
+		drm_atomic_set_fb_for_plane(plane_state, NULL);
+	}
+
+	ret = drm_atomic_commit(state);
+free:
+	drm_atomic_commit_put(state);
+	return ret;
+}
+EXPORT_SYMBOL(drm_atomic_disable_all);
+
+/**
+ * drm_atomic_shutdown - shutdown all CRTC
+ * @dev: DRM device
+ *
+ * This shuts down all CRTC, which is useful for driver unloading. Shutdown on
+ * suspend should instead be handled with drm_atomic_helper_suspend(), since
+ * that also takes a snapshot of the modeset state to be restored on resume.
+ *
+ * This is just a convenience wrapper around drm_atomic_helper_disable_all(),
+ * and it is the atomic version of drm_helper_force_disable_all().
+ */
+void drm_atomic_shutdown(struct drm_device *dev)
+{
+	struct drm_modeset_acquire_ctx ctx;
+	int ret;
+
+	if (dev == NULL)
+		return;
+
+	DRM_MODESET_LOCK_ALL_BEGIN(dev, ctx, 0, ret);
+
+	ret = drm_atomic_disable_all(dev, &ctx);
+	if (ret)
+		drm_err(dev,
+			"Disabling all crtc's during unload failed with %i\n",
+			ret);
+
+	DRM_MODESET_LOCK_ALL_END(dev, ctx, ret);
+}
+EXPORT_SYMBOL(drm_atomic_shutdown);
+
 static void drm_atomic_private_obj_print_state(struct drm_printer *p,
 					       const struct drm_private_state *state)
 {
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 51f39edc31ed..afedfab9b568 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -3533,6 +3533,8 @@ EXPORT_SYMBOL(drm_atomic_helper_set_config);
  * @dev: DRM device
  * @ctx: lock acquisition context
  *
+ * Deprecated wrapper to drm_atomic_disable_all().
+ *
  * Loops through all connectors, finding those that aren't turned off and then
  * turns them off by setting their DPMS mode to OFF and deactivating the CRTC
  * that they are connected to.
@@ -3554,61 +3556,7 @@ EXPORT_SYMBOL(drm_atomic_helper_set_config);
 int drm_atomic_helper_disable_all(struct drm_device *dev,
 				  struct drm_modeset_acquire_ctx *ctx)
 {
-	struct drm_atomic_commit *state;
-	struct drm_connector_state *conn_state;
-	struct drm_connector *conn;
-	struct drm_plane_state *plane_state;
-	struct drm_plane *plane;
-	struct drm_crtc_state *crtc_state;
-	struct drm_crtc *crtc;
-	int ret, i;
-
-	state = drm_atomic_commit_alloc(dev);
-	if (!state)
-		return -ENOMEM;
-
-	state->acquire_ctx = ctx;
-
-	drm_for_each_crtc(crtc, dev) {
-		crtc_state = drm_atomic_get_crtc_state(state, crtc);
-		if (IS_ERR(crtc_state)) {
-			ret = PTR_ERR(crtc_state);
-			goto free;
-		}
-
-		crtc_state->active = false;
-
-		ret = drm_atomic_set_mode_prop_for_crtc(crtc_state, NULL);
-		if (ret < 0)
-			goto free;
-
-		ret = drm_atomic_add_affected_planes(state, crtc);
-		if (ret < 0)
-			goto free;
-
-		ret = drm_atomic_add_affected_connectors(state, crtc);
-		if (ret < 0)
-			goto free;
-	}
-
-	for_each_new_connector_in_state(state, conn, conn_state, i) {
-		ret = drm_atomic_set_crtc_for_connector(conn_state, NULL);
-		if (ret < 0)
-			goto free;
-	}
-
-	for_each_new_plane_in_state(state, plane, plane_state, i) {
-		ret = drm_atomic_set_crtc_for_plane(plane_state, NULL);
-		if (ret < 0)
-			goto free;
-
-		drm_atomic_set_fb_for_plane(plane_state, NULL);
-	}
-
-	ret = drm_atomic_commit(state);
-free:
-	drm_atomic_commit_put(state);
-	return ret;
+	return drm_atomic_disable_all(dev, ctx);
 }
 EXPORT_SYMBOL(drm_atomic_helper_disable_all);
 
@@ -3664,6 +3612,8 @@ EXPORT_SYMBOL(drm_atomic_helper_reset_crtc);
  * drm_atomic_helper_shutdown - shutdown all CRTC
  * @dev: DRM device
  *
+ * Deprecated wrapper to drm_atomic_shutdown().
+ *
  * This shuts down all CRTC, which is useful for driver unloading. Shutdown on
  * suspend should instead be handled with drm_atomic_helper_suspend(), since
  * that also takes a snapshot of the modeset state to be restored on resume.
@@ -3673,21 +3623,7 @@ EXPORT_SYMBOL(drm_atomic_helper_reset_crtc);
  */
 void drm_atomic_helper_shutdown(struct drm_device *dev)
 {
-	struct drm_modeset_acquire_ctx ctx;
-	int ret;
-
-	if (dev == NULL)
-		return;
-
-	DRM_MODESET_LOCK_ALL_BEGIN(dev, ctx, 0, ret);
-
-	ret = drm_atomic_helper_disable_all(dev, &ctx);
-	if (ret)
-		drm_err(dev,
-			"Disabling all crtc's during unload failed with %i\n",
-			ret);
-
-	DRM_MODESET_LOCK_ALL_END(dev, ctx, ret);
+	return drm_atomic_shutdown(dev);
 }
 EXPORT_SYMBOL(drm_atomic_helper_shutdown);
 
diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h
index 1a80a8cdf269..9eb3d1bfa084 100644
--- a/include/drm/drm_atomic.h
+++ b/include/drm/drm_atomic.h
@@ -1373,5 +1373,8 @@ drm_atomic_get_old_bridge_state(const struct drm_atomic_commit *state,
 struct drm_bridge_state *
 drm_atomic_get_new_bridge_state(const struct drm_atomic_commit *state,
 				struct drm_bridge *bridge);
+int drm_atomic_disable_all(struct drm_device *dev,
+			   struct drm_modeset_acquire_ctx *ctx);
+void drm_atomic_shutdown(struct drm_device *dev);
 
 #endif /* DRM_ATOMIC_H_ */

-- 
2.54.0