[PATCH v5 2/4] drm/atomic-helper: Introduce drm_atomic_helper_reset_crtc()

Herve Codina
2025-02-03T16:16:15Z

drm_atomic_helper_reset_crtc() allows to reset the CRTC active outputs.

This resets all active components available between the CRTC and
connectors.

Signed-off-by: Herve Codina <herve.codina@bootlin.com>
---
drivers/gpu/drm/drm_atomic_helper.c | 41 +++++++++++++++++++++++++++++
include/drm/drm_atomic_helper.h | 2 ++
2 files changed, 43 insertions(+)

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 5186d2114a50..0a636c398578 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -3362,6 +3362,47 @@ int drm_atomic_helper_disable_all(struct drm_device *dev,
}
EXPORT_SYMBOL(drm_atomic_helper_disable_all);

+/**
+ * drm_atomic_helper_reset_crtc - reset the active outputs of a CRTC
+ * @crtc: DRM CRTC
+ * @ctx: lock acquisition context
+ *
+ * Reset the active outputs by indicating that connectors have changed.
+ * This implies a reset of all active components available between the CRTC and
+ * connectors.
+ *
+ * Returns:
+ * 0 on success or a negative error code on failure.
+ */
+int drm_atomic_helper_reset_crtc(struct drm_crtc *crtc,
+ struct drm_modeset_acquire_ctx *ctx)
+{
+ struct drm_atomic_state *state;
+ struct drm_crtc_state *crtc_state;
+ int ret;
+
+ state = drm_atomic_state_alloc(crtc->dev);
+ if (!state)
+ return -ENOMEM;
+
+ state->acquire_ctx = ctx;
+
+ crtc_state = drm_atomic_get_crtc_state(state, crtc);
+ if (IS_ERR(crtc_state)) {
+ ret = PTR_ERR(crtc_state);
+ goto out;
+ }
+
+ crtc_state->connectors_changed = true;
+
+ ret = drm_atomic_commit(state);
+out:
+ drm_atomic_state_put(state);
+
+ return ret;
+}
+EXPORT_SYMBOL(drm_atomic_helper_reset_crtc);
+
/**
* drm_atomic_helper_shutdown - shutdown all CRTC
* @dev: DRM device
diff --git a/include/drm/drm_atomic_helper.h b/include/drm/drm_atomic_helper.h
index 9aa0a05aa072..53382fe93537 100644
--- a/include/drm/drm_atomic_helper.h
+++ b/include/drm/drm_atomic_helper.h
@@ -139,6 +139,8 @@ int drm_atomic_helper_set_config(struct drm_mode_set *set,

int drm_atomic_helper_disable_all(struct drm_device *dev,
struct drm_modeset_acquire_ctx *ctx);
+int drm_atomic_helper_reset_crtc(struct drm_crtc *crtc,
+ struct drm_modeset_acquire_ctx *ctx);
void drm_atomic_helper_shutdown(struct drm_device *dev);
struct drm_atomic_state *
drm_atomic_helper_duplicate_state(struct drm_device *dev,
--
2.47.1