[PATCH v4 05/13] drm/atomic: Create function to insert plane state into a commit

From: Maxime Ripard

Date: Fri Sep 18 2026 - 10:33:00 EST


drm_atomic_get_plane_state() allocates a new plane state by
duplicating the current one and inserts it into the atomic commit as
a single operation.

However, a later change will need to insert a plane state into a
commit without going through the full allocation and duplication path
in drm_atomic_get_plane_state().

Extract the state insertion logic into a new static
drm_atomic_commit_set_plane_state() helper, and convert
drm_atomic_get_plane_state() to use it.

Reviewed-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
Signed-off-by: Maxime Ripard <mripard@xxxxxxxxxx>
---
drivers/gpu/drm/drm_atomic.c | 23 +++++++++++++++++------
1 file changed, 17 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 178eca95d0e3..b26458ee98d8 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -628,10 +628,25 @@ static int drm_atomic_connector_check(struct drm_connector *connector,
}

return 0;
}

+static void drm_atomic_commit_set_plane_state(struct drm_atomic_commit *commit,
+ struct drm_plane *plane,
+ struct drm_plane_state *plane_state)
+{
+ int index = drm_plane_index(plane);
+
+ drm_modeset_lock_assert_held(&plane->mutex);
+
+ commit->planes[index].state_to_destroy = plane_state;
+ commit->planes[index].old_state = plane->state;
+ commit->planes[index].new_state = plane_state;
+ commit->planes[index].ptr = plane;
+ plane_state->state = commit;
+}
+
/**
* drm_atomic_get_plane_state - get plane state
* @state: global atomic state object
* @plane: plane to get state object for
*
@@ -646,11 +661,11 @@ static int drm_atomic_connector_check(struct drm_connector *connector,
*/
struct drm_plane_state *
drm_atomic_get_plane_state(struct drm_atomic_commit *state,
struct drm_plane *plane)
{
- int ret, index = drm_plane_index(plane);
+ int ret;
struct drm_plane_state *plane_state;

WARN_ON(!state->acquire_ctx);
drm_WARN_ON(state->dev, state->checked);

@@ -669,15 +684,11 @@ drm_atomic_get_plane_state(struct drm_atomic_commit *state,

plane_state = plane->funcs->atomic_duplicate_state(plane);
if (!plane_state)
return ERR_PTR(-ENOMEM);

- state->planes[index].state_to_destroy = plane_state;
- state->planes[index].ptr = plane;
- state->planes[index].old_state = plane->state;
- state->planes[index].new_state = plane_state;
- plane_state->state = state;
+ drm_atomic_commit_set_plane_state(state, plane, plane_state);

drm_dbg_atomic(plane->dev, "Added [PLANE:%d:%s] %p state to %p\n",
plane->base.id, plane->name, plane_state, state);

if (plane_state->crtc) {

--
2.55.0