From ce09d7667dd225564df1e20b8185d4ce7be886cc Mon Sep 17 00:00:00 2001 From: Maarten Lankhorst Date: Thu, 6 Apr 2017 13:19:03 +0200 Subject: [PATCH] drm/atomic: Add connector atomic_check function, v2. The atomic_check function is useful for implementing properties, but it can be used for other connector modeset related checks as well. Similar to plane check functions, on a modeset atomic_check() is always called. Changes since v1: - Make sure atomic_check() is called on any modeset. Signed-off-by: Maarten Lankhorst Reviewed-by: Dhinakaran Pandiyan Reviewed-by: Daniel Vetter Signed-off-by: Sean Paul Link: http://patchwork.freedesktop.org/patch/msgid/1491477543-31257-5-git-send-email-maarten.lankhorst@linux.intel.com --- drivers/gpu/drm/drm_atomic_helper.c | 44 +++++++++++++++++++++--- include/drm/drm_modeset_helper_vtables.h | 34 ++++++++++++++++++ 2 files changed, 74 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index ff3c6eb5b6bd..8be9719284b0 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -459,10 +459,20 @@ mode_fixup(struct drm_atomic_state *state) * * Check the state object to see if the requested state is physically possible. * This does all the crtc and connector related computations for an atomic - * update and adds any additional connectors needed for full modesets and calls - * down into &drm_crtc_helper_funcs.mode_fixup and - * &drm_encoder_helper_funcs.mode_fixup or - * &drm_encoder_helper_funcs.atomic_check functions of the driver backend. + * update and adds any additional connectors needed for full modesets. It calls + * the various per-object callbacks in the follow order: + * + * 1. &drm_connector_helper_funcs.atomic_best_encoder for determining the new encoder. + * 2. &drm_connector_helper_funcs.atomic_check to validate the connector state. + * 3. If it's determined a modeset is needed then all connectors on the affected crtc + * crtc are added and &drm_connector_helper_funcs.atomic_check is run on them. + * 4. &drm_bridge_funcs.mode_fixup is called on all encoder bridges. + * 5. &drm_encoder_helper_funcs.atomic_check is called to validate any encoder state. + * This function is only called when the encoder will be part of a configured crtc, + * it must not be used for implementing connector property validation. + * If this function is NULL, &drm_atomic_encoder_helper_funcs.mode_fixup is called + * instead. + * 6. &drm_crtc_helper_funcs.mode_fixup is called last, to fix up the mode with crtc constraints. * * &drm_crtc_state.mode_changed is set when the input mode is changed. * &drm_crtc_state.connectors_changed is set when a connector is added or @@ -492,6 +502,7 @@ drm_atomic_helper_check_modeset(struct drm_device *dev, struct drm_connector *connector; struct drm_connector_state *old_connector_state, *new_connector_state; int i, ret; + unsigned connectors_mask = 0; for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) { bool has_connectors = @@ -538,6 +549,8 @@ drm_atomic_helper_check_modeset(struct drm_device *dev, return ret; for_each_oldnew_connector_in_state(state, connector, old_connector_state, new_connector_state, i) { + const struct drm_connector_helper_funcs *funcs = connector->helper_private; + /* * This only sets crtc->connectors_changed for routing changes, * drivers must set crtc->connectors_changed themselves when @@ -555,6 +568,13 @@ drm_atomic_helper_check_modeset(struct drm_device *dev, new_connector_state->link_status) new_crtc_state->connectors_changed = true; } + + if (funcs->atomic_check) + ret = funcs->atomic_check(connector, new_connector_state); + if (ret) + return ret; + + connectors_mask += BIT(i); } /* @@ -581,6 +601,22 @@ drm_atomic_helper_check_modeset(struct drm_device *dev, return ret; } + /* + * Iterate over all connectors again, to make sure atomic_check() + * has been called on them when a modeset is forced. + */ + for_each_oldnew_connector_in_state(state, connector, old_connector_state, new_connector_state, i) { + const struct drm_connector_helper_funcs *funcs = connector->helper_private; + + if (connectors_mask & BIT(i)) + continue; + + if (funcs->atomic_check) + ret = funcs->atomic_check(connector, new_connector_state); + if (ret) + return ret; + } + return mode_fixup(state); } EXPORT_SYMBOL(drm_atomic_helper_check_modeset); diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h index 7847babd893c..c01c328f6cc8 100644 --- a/include/drm/drm_modeset_helper_vtables.h +++ b/include/drm/drm_modeset_helper_vtables.h @@ -872,6 +872,40 @@ struct drm_connector_helper_funcs { */ struct drm_encoder *(*atomic_best_encoder)(struct drm_connector *connector, struct drm_connector_state *connector_state); + + /** + * @atomic_check: + * + * This hook is used to validate connector state. This function is + * called from &drm_atomic_helper_check_modeset, and is called when + * a connector property is set, or a modeset on the crtc is forced. + * + * Because &drm_atomic_helper_check_modeset may be called multiple times, + * this function should handle being called multiple times as well. + * + * This function is also allowed to inspect any other object's state and + * can add more state objects to the atomic commit if needed. Care must + * be taken though to ensure that state check and compute functions for + * these added states are all called, and derived state in other objects + * all updated. Again the recommendation is to just call check helpers + * until a maximal configuration is reached. + * + * NOTE: + * + * This function is called in the check phase of an atomic update. The + * driver is not allowed to change anything outside of the free-standing + * state objects passed-in or assembled in the overall &drm_atomic_state + * update tracking structure. + * + * RETURNS: + * + * 0 on success, -EINVAL if the state or the transition can't be + * supported, -ENOMEM on memory allocation failure and -EDEADLK if an + * attempt to obtain another state object ran into a &drm_modeset_lock + * deadlock. + */ + int (*atomic_check)(struct drm_connector *connector, + struct drm_connector_state *state); }; /**