Commit d6b9af10 authored by Thomas Zimmermann's avatar Thomas Zimmermann
Browse files

drm/atomic-helper: Add helper drm_atomic_helper_check_crtc_state() 



Add drm_atomic_helper_check_crtc_state(), which contains tests common
to many CRTCs. The first added test verifies that an enabled CRTC has
at least one enabled primary plane.

Signed-off-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Acked-by: default avatarJocelyn Falempe <jfalempe@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220617103226.25617-2-tzimmermann@suse.de
parent ae25885b

drivers/gpu/drm/drm_atomic_helper.c

+55 −0
Original line number Diff line number Diff line
@@ -877,6 +877,61 @@ int drm_atomic_helper_check_plane_state(struct drm_plane_state *plane_state, 
}

EXPORT_SYMBOL(drm_atomic_helper_check_plane_state);



/**

 * drm_atomic_helper_check_crtc_state() - Check CRTC state for validity

 * @crtc_state: CRTC state to check

 * @can_disable_primary_planes: can the CRTC be enabled without a primary plane?

 *

 * Checks that a desired CRTC update is valid. Drivers that provide

 * their own CRTC handling rather than helper-provided implementations may

 * still wish to call this function to avoid duplication of error checking

 * code.

 *

 * Note that @can_disable_primary_planes only tests if the CRTC can be

 * enabled without a primary plane. To test if a primary plane can be updated

 * without a CRTC, use drm_atomic_helper_check_plane_state() in the plane's

 * atomic check.

 *

 * RETURNS:

 * Zero if update appears valid, error code on failure

 */

int drm_atomic_helper_check_crtc_state(struct drm_crtc_state *crtc_state,

				       bool can_disable_primary_planes)

{

	struct drm_device *dev = crtc_state->crtc->dev;

	struct drm_atomic_state *state = crtc_state->state;



	if (!crtc_state->enable)

		return 0;



	/* needs at least one primary plane to be enabled */

	if (!can_disable_primary_planes) {

		bool has_primary_plane = false;

		struct drm_plane *plane;



		drm_for_each_plane_mask(plane, dev, crtc_state->plane_mask) {

			struct drm_plane_state *plane_state;



			if (plane->type != DRM_PLANE_TYPE_PRIMARY)

				continue;

			plane_state = drm_atomic_get_plane_state(state, plane);

			if (IS_ERR(plane_state))

				return PTR_ERR(plane_state);

			if (plane_state->fb && plane_state->crtc) {

				has_primary_plane = true;

				break;

			}

		}

		if (!has_primary_plane) {

			drm_dbg_kms(dev, "Cannot enable CRTC without a primary plane.\n");

			return -EINVAL;

		}

	}



	return 0;

}

EXPORT_SYMBOL(drm_atomic_helper_check_crtc_state);



/**

 * drm_atomic_helper_check_planes - validate state object for planes changes

 * @dev: DRM device

include/drm/drm_atomic_helper.h

+2 −0
Original line number Diff line number Diff line
@@ -46,6 +46,8 @@ int drm_atomic_helper_check_plane_state(struct drm_plane_state *plane_state, 
					int max_scale,

					bool can_position,

					bool can_update_disabled);

int drm_atomic_helper_check_crtc_state(struct drm_crtc_state *crtc_state,

				       bool can_disable_primary_plane);

int drm_atomic_helper_check_planes(struct drm_device *dev,

			       struct drm_atomic_state *state);

int drm_atomic_helper_check(struct drm_device *dev,