diff options
Diffstat (limited to 'drivers/gpu/drm/drm_atomic_helper.c')
-rw-r--r-- | drivers/gpu/drm/drm_atomic_helper.c | 566 |
1 files changed, 477 insertions, 89 deletions
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index ddfa0d120e39..de7fddce3cef 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -110,8 +110,10 @@ static int handle_conflicting_encoders(struct drm_atomic_state *state, if (funcs->atomic_best_encoder) new_encoder = funcs->atomic_best_encoder(connector, conn_state); - else + else if (funcs->best_encoder) new_encoder = funcs->best_encoder(connector); + else + new_encoder = drm_atomic_helper_best_encoder(connector); if (new_encoder) { if (encoder_mask & (1 << drm_encoder_index(new_encoder))) { @@ -298,8 +300,10 @@ update_connector_routing(struct drm_atomic_state *state, if (funcs->atomic_best_encoder) new_encoder = funcs->atomic_best_encoder(connector, connector_state); - else + else if (funcs->best_encoder) new_encoder = funcs->best_encoder(connector); + else + new_encoder = drm_atomic_helper_best_encoder(connector); if (!new_encoder) { DRM_DEBUG_ATOMIC("No suitable encoder found for [CONNECTOR:%d:%s]\n", @@ -414,6 +418,9 @@ mode_fixup(struct drm_atomic_state *state) for_each_crtc_in_state(state, crtc, crtc_state, i) { const struct drm_crtc_helper_funcs *funcs; + if (!crtc_state->enable) + continue; + if (!crtc_state->mode_changed && !crtc_state->connectors_changed) continue; @@ -458,7 +465,7 @@ mode_fixup(struct drm_atomic_state *state) * times for the same update, e.g. when the ->atomic_check functions depend upon * the adjusted dotclock for fifo space allocation and watermark computation. * - * RETURNS + * RETURNS: * Zero for success or -errno */ int @@ -572,7 +579,7 @@ EXPORT_SYMBOL(drm_atomic_helper_check_modeset); * It also sets crtc_state->planes_changed to indicate that a crtc has * updated planes. * - * RETURNS + * RETURNS: * Zero for success or -errno */ int @@ -611,7 +618,7 @@ drm_atomic_helper_check_planes(struct drm_device *dev, if (!funcs || !funcs->atomic_check) continue; - ret = funcs->atomic_check(crtc, state->crtc_states[i]); + ret = funcs->atomic_check(crtc, crtc_state); if (ret) { DRM_DEBUG_ATOMIC("[CRTC:%d:%s] atomic driver check failed\n", crtc->base.id, crtc->name); @@ -640,7 +647,7 @@ EXPORT_SYMBOL(drm_atomic_helper_check_planes); * ->atomic_check functions depend upon an updated adjusted_mode.clock to * e.g. properly compute watermarks. * - * RETURNS + * RETURNS: * Zero for success or -errno */ int drm_atomic_helper_check(struct drm_device *dev, @@ -1113,22 +1120,17 @@ drm_atomic_helper_wait_for_vblanks(struct drm_device *dev, EXPORT_SYMBOL(drm_atomic_helper_wait_for_vblanks); /** - * drm_atomic_helper_commit - commit validated state object - * @dev: DRM device - * @state: the driver state object - * @nonblocking: whether nonblocking behavior is requested. + * drm_atomic_helper_commit_tail - commit atomic update to hardware + * @state: new modeset state to be committed * - * This function commits a with drm_atomic_helper_check() pre-validated state - * object. This can still fail when e.g. the framebuffer reservation fails. For - * now this doesn't implement nonblocking commits. + * This is the default implemenation for the ->atomic_commit_tail() hook of the + * &drm_mode_config_helper_funcs vtable. * - * Note that right now this function does not support nonblocking commits, hence - * driver writers must implement their own version for now. Also note that the - * default ordering of how the various stages are called is to match the legacy - * modeset helper library closest. One peculiarity of that is that it doesn't - * mesh well with runtime PM at all. + * Note that the default ordering of how the various stages are called is to + * match the legacy modeset helper library closest. One peculiarity of that is + * that it doesn't mesh well with runtime PM at all. * - * For drivers supporting runtime PM the recommended sequence is + * For drivers supporting runtime PM the recommended sequence is instead :: * * drm_atomic_helper_commit_modeset_disables(dev, state); * @@ -1136,9 +1138,75 @@ EXPORT_SYMBOL(drm_atomic_helper_wait_for_vblanks); * * drm_atomic_helper_commit_planes(dev, state, true); * - * See the kerneldoc entries for these three functions for more details. + * for committing the atomic update to hardware. See the kerneldoc entries for + * these three functions for more details. + */ +void drm_atomic_helper_commit_tail(struct drm_atomic_state *state) +{ + struct drm_device *dev = state->dev; + + drm_atomic_helper_commit_modeset_disables(dev, state); + + drm_atomic_helper_commit_planes(dev, state, false); + + drm_atomic_helper_commit_modeset_enables(dev, state); + + drm_atomic_helper_commit_hw_done(state); + + drm_atomic_helper_wait_for_vblanks(dev, state); + + drm_atomic_helper_cleanup_planes(dev, state); +} +EXPORT_SYMBOL(drm_atomic_helper_commit_tail); + +static void commit_tail(struct drm_atomic_state *state) +{ + struct drm_device *dev = state->dev; + struct drm_mode_config_helper_funcs *funcs; + + funcs = dev->mode_config.helper_private; + + drm_atomic_helper_wait_for_fences(dev, state); + + drm_atomic_helper_wait_for_dependencies(state); + + if (funcs && funcs->atomic_commit_tail) + funcs->atomic_commit_tail(state); + else + drm_atomic_helper_commit_tail(state); + + drm_atomic_helper_commit_cleanup_done(state); + + drm_atomic_state_free(state); +} + +static void commit_work(struct work_struct *work) +{ + struct drm_atomic_state *state = container_of(work, + struct drm_atomic_state, + commit_work); + commit_tail(state); +} + +/** + * drm_atomic_helper_commit - commit validated state object + * @dev: DRM device + * @state: the driver state object + * @nonblock: whether nonblocking behavior is requested. + * + * This function commits a with drm_atomic_helper_check() pre-validated state + * object. This can still fail when e.g. the framebuffer reservation fails. This + * function implements nonblocking commits, using + * drm_atomic_helper_setup_commit() and related functions. + * + * Note that right now this function does not support nonblocking commits, hence + * driver writers must implement their own version for now. + * + * Committing the actual hardware state is done through the + * ->atomic_commit_tail() callback of the &drm_mode_config_helper_funcs vtable, + * or it's default implementation drm_atomic_helper_commit_tail(). * - * RETURNS + * RETURNS: * Zero for success or -errno. */ int drm_atomic_helper_commit(struct drm_device *dev, @@ -1147,8 +1215,11 @@ int drm_atomic_helper_commit(struct drm_device *dev, { int ret; - if (nonblock) - return -EBUSY; + ret = drm_atomic_helper_setup_commit(state, nonblock); + if (ret) + return ret; + + INIT_WORK(&state->commit_work, commit_work); ret = drm_atomic_helper_prepare_planes(dev, state); if (ret) @@ -1160,7 +1231,7 @@ int drm_atomic_helper_commit(struct drm_device *dev, * the software side now. */ - drm_atomic_helper_swap_state(dev, state); + drm_atomic_helper_swap_state(state, true); /* * Everything below can be run asynchronously without the need to grab @@ -1176,21 +1247,16 @@ int drm_atomic_helper_commit(struct drm_device *dev, * update. Which is important since compositors need to figure out the * composition of the next frame right after having submitted the * current layout. + * + * NOTE: Commit work has multiple phases, first hardware commit, then + * cleanup. We want them to overlap, hence need system_unbound_wq to + * make sure work items don't artifically stall on each another. */ - drm_atomic_helper_wait_for_fences(dev, state); - - drm_atomic_helper_commit_modeset_disables(dev, state); - - drm_atomic_helper_commit_planes(dev, state, false); - - drm_atomic_helper_commit_modeset_enables(dev, state); - - drm_atomic_helper_wait_for_vblanks(dev, state); - - drm_atomic_helper_cleanup_planes(dev, state); - - drm_atomic_state_free(state); + if (nonblock) + queue_work(system_unbound_wq, &state->commit_work); + else + commit_tail(state); return 0; } @@ -1199,12 +1265,7 @@ EXPORT_SYMBOL(drm_atomic_helper_commit); /** * DOC: implementing nonblocking commit * - * For now the atomic helpers don't support nonblocking commit directly. If - * there is real need it could be added though, using the dma-buf fence - * infrastructure for generic synchronization with outstanding rendering. - * - * For now drivers have to implement nonblocking commit themselves, with the - * following sequence being the recommended one: + * Nonblocking atomic commits have to be implemented in the following sequence: * * 1. Run drm_atomic_helper_prepare_planes() first. This is the only function * which commit needs to call which can fail, so we want to run it first and @@ -1216,10 +1277,14 @@ EXPORT_SYMBOL(drm_atomic_helper_commit); * cancelled updates. Note that it is important to ensure that the framebuffer * cleanup is still done when cancelling. * - * For sufficient parallelism it is recommended to have a work item per crtc - * (for updates which don't touch global state) and a global one. Then we only - * need to synchronize with the crtc work items for changed crtcs and the global - * work item, which allows nice concurrent updates on disjoint sets of crtcs. + * Asynchronous workers need to have sufficient parallelism to be able to run + * different atomic commits on different CRTCs in parallel. The simplest way to + * achive this is by running them on the &system_unbound_wq work queue. Note + * that drivers are not required to split up atomic commits and run an + * individual commit in parallel - userspace is supposed to do that if it cares. + * But it might be beneficial to do that for modesets, since those necessarily + * must be done as one global operation, and enabling or disabling a CRTC can + * take a long time. But even that is not required. * * 3. The software state is updated synchronously with * drm_atomic_helper_swap_state(). Doing this under the protection of all modeset @@ -1232,8 +1297,310 @@ EXPORT_SYMBOL(drm_atomic_helper_commit); * commit helpers: a) pre-plane commit b) plane commit c) post-plane commit and * then cleaning up the framebuffers after the old framebuffer is no longer * being displayed. + * + * The above scheme is implemented in the atomic helper libraries in + * drm_atomic_helper_commit() using a bunch of helper functions. See + * drm_atomic_helper_setup_commit() for a starting point. */ +static int stall_checks(struct drm_crtc *crtc, bool nonblock) +{ + struct drm_crtc_commit *commit, *stall_commit = NULL; + bool completed = true; + int i; + long ret = 0; + + spin_lock(&crtc->commit_lock); + i = 0; + list_for_each_entry(commit, &crtc->commit_list, commit_entry) { + if (i == 0) { + completed = try_wait_for_completion(&commit->flip_done); + /* Userspace is not allowed to get ahead of the previous + * commit with nonblocking ones. */ + if (!completed && nonblock) { + spin_unlock(&crtc->commit_lock); + return -EBUSY; + } + } else if (i == 1) { + stall_commit = commit; + drm_crtc_commit_get(stall_commit); + break; + } + + i++; + } + spin_unlock(&crtc->commit_lock); + + if (!stall_commit) + return 0; + + /* We don't want to let commits get ahead of cleanup work too much, + * stalling on 2nd previous commit means triple-buffer won't ever stall. + */ + ret = wait_for_completion_interruptible_timeout(&stall_commit->cleanup_done, + 10*HZ); + if (ret == 0) + DRM_ERROR("[CRTC:%d:%s] cleanup_done timed out\n", + crtc->base.id, crtc->name); + + drm_crtc_commit_put(stall_commit); + + return ret < 0 ? ret : 0; +} + +/** + * drm_atomic_helper_setup_commit - setup possibly nonblocking commit + * @state: new modeset state to be committed + * @nonblock: whether nonblocking behavior is requested. + * + * This function prepares @state to be used by the atomic helper's support for + * nonblocking commits. Drivers using the nonblocking commit infrastructure + * should always call this function from their ->atomic_commit hook. + * + * To be able to use this support drivers need to use a few more helper + * functions. drm_atomic_helper_wait_for_dependencies() must be called before + * actually committing the hardware state, and for nonblocking commits this call + * must be placed in the async worker. See also drm_atomic_helper_swap_state() + * and it's stall parameter, for when a driver's commit hooks look at the + * ->state pointers of struct &drm_crtc, &drm_plane or &drm_connector directly. + * + * Completion of the hardware commit step must be signalled using + * drm_atomic_helper_commit_hw_done(). After this step the driver is not allowed + * to read or change any permanent software or hardware modeset state. The only + * exception is state protected by other means than &drm_modeset_lock locks. + * Only the free standing @state with pointers to the old state structures can + * be inspected, e.g. to clean up old buffers using + * drm_atomic_helper_cleanup_planes(). + * + * At the very end, before cleaning up @state drivers must call + * drm_atomic_helper_commit_cleanup_done(). + * + * This is all implemented by in drm_atomic_helper_commit(), giving drivers a + * complete and esay-to-use default implementation of the atomic_commit() hook. + * + * The tracking of asynchronously executed and still pending commits is done + * using the core structure &drm_crtc_commit. + * + * By default there's no need to clean up resources allocated by this function + * explicitly: drm_atomic_state_default_clear() will take care of that + * automatically. + * + * Returns: + * + * 0 on success. -EBUSY when userspace schedules nonblocking commits too fast, + * -ENOMEM on allocation failures and -EINTR when a signal is pending. + */ +int drm_atomic_helper_setup_commit(struct drm_atomic_state *state, + bool nonblock) +{ + struct drm_crtc *crtc; + struct drm_crtc_state *crtc_state; + struct drm_crtc_commit *commit; + int i, ret; + + for_each_crtc_in_state(state, crtc, crtc_state, i) { + commit = kzalloc(sizeof(*commit), GFP_KERNEL); + if (!commit) + return -ENOMEM; + + init_completion(&commit->flip_done); + init_completion(&commit->hw_done); + init_completion(&commit->cleanup_done); + INIT_LIST_HEAD(&commit->commit_entry); + kref_init(&commit->ref); + commit->crtc = crtc; + + state->crtcs[i].commit = commit; + + ret = stall_checks(crtc, nonblock); + if (ret) + return ret; + + /* Drivers only send out events when at least either current or + * new CRTC state is active. Complete right away if everything + * stays off. */ + if (!crtc->state->active && !crtc_state->active) { + complete_all(&commit->flip_done); + continue; + } + + /* Legacy cursor updates are fully unsynced. */ + if (state->legacy_cursor_update) { + complete_all(&commit->flip_done); + continue; + } + + if (!crtc_state->event) { + commit->event = kzalloc(sizeof(*commit->event), + GFP_KERNEL); + if (!commit->event) + return -ENOMEM; + + crtc_state->event = commit->event; + } + + crtc_state->event->base.completion = &commit->flip_done; + } + + return 0; +} +EXPORT_SYMBOL(drm_atomic_helper_setup_commit); + + +static struct drm_crtc_commit *preceeding_commit(struct drm_crtc *crtc) +{ + struct drm_crtc_commit *commit; + int i = 0; + + list_for_each_entry(commit, &crtc->commit_list, commit_entry) { + /* skip the first entry, that's the current commit */ + if (i == 1) + return commit; + i++; + } + + return NULL; +} + +/** + * drm_atomic_helper_wait_for_dependencies - wait for required preceeding commits + * @state: new modeset state to be committed + * + * This function waits for all preceeding commits that touch the same CRTC as + * @state to both be committed to the hardware (as signalled by + * drm_atomic_helper_commit_hw_done) and executed by the hardware (as signalled + * by calling drm_crtc_vblank_send_event on the event member of + * &drm_crtc_state). + * + * This is part of the atomic helper support for nonblocking commits, see + * drm_atomic_helper_setup_commit() for an overview. + */ +void drm_atomic_helper_wait_for_dependencies(struct drm_atomic_state *state) +{ + struct drm_crtc *crtc; + struct drm_crtc_state *crtc_state; + struct drm_crtc_commit *commit; + int i; + long ret; + + for_each_crtc_in_state(state, crtc, crtc_state, i) { + spin_lock(&crtc->commit_lock); + commit = preceeding_commit(crtc); + if (commit) + drm_crtc_commit_get(commit); + spin_unlock(&crtc->commit_lock); + + if (!commit) + continue; + + ret = wait_for_completion_timeout(&commit->hw_done, + 10*HZ); + if (ret == 0) + DRM_ERROR("[CRTC:%d:%s] hw_done timed out\n", + crtc->base.id, crtc->name); + + /* Currently no support for overwriting flips, hence + * stall for previous one to execute completely. */ + ret = wait_for_completion_timeout(&commit->flip_done, + 10*HZ); + if (ret == 0) + DRM_ERROR("[CRTC:%d:%s] flip_done timed out\n", + crtc->base.id, crtc->name); + + drm_crtc_commit_put(commit); + } +} +EXPORT_SYMBOL(drm_atomic_helper_wait_for_dependencies); + +/** + * drm_atomic_helper_commit_hw_done - setup possible nonblocking commit + * @state: new modeset state to be committed + * + * This function is used to signal completion of the hardware commit step. After + * this step the driver is not allowed to read or change any permanent software + * or hardware modeset state. The only exception is state protected by other + * means than &drm_modeset_lock locks. + * + * Drivers should try to postpone any expensive or delayed cleanup work after + * this function is called. + * + * This is part of the atomic helper support for nonblocking commits, see + * drm_atomic_helper_setup_commit() for an overview. + */ +void drm_atomic_helper_commit_hw_done(struct drm_atomic_state *state) +{ + struct drm_crtc *crtc; + struct drm_crtc_state *crtc_state; + struct drm_crtc_commit *commit; + int i; + + for_each_crtc_in_state(state, crtc, crtc_state, i) { + commit = state->crtcs[i].commit; + if (!commit) + continue; + + /* backend must have consumed any event by now */ + WARN_ON(crtc->state->event); + spin_lock(&crtc->commit_lock); + complete_all(&commit->hw_done); + spin_unlock(&crtc->commit_lock); + } +} +EXPORT_SYMBOL(drm_atomic_helper_commit_hw_done); + +/** + * drm_atomic_helper_commit_cleanup_done - signal completion of commit + * @state: new modeset state to be committed + * + * This signals completion of the atomic update @state, including any cleanup + * work. If used, it must be called right before calling + * drm_atomic_state_free(). + * + * This is part of the atomic helper support for nonblocking commits, see + * drm_atomic_helper_setup_commit() for an overview. + */ +void drm_atomic_helper_commit_cleanup_done(struct drm_atomic_state *state) +{ + struct drm_crtc *crtc; + struct drm_crtc_state *crtc_state; + struct drm_crtc_commit *commit; + int i; + long ret; + + for_each_crtc_in_state(state, crtc, crtc_state, i) { + commit = state->crtcs[i].commit; + if (WARN_ON(!commit)) + continue; + + spin_lock(&crtc->commit_lock); + complete_all(&commit->cleanup_done); + WARN_ON(!try_wait_for_completion(&commit->hw_done)); + + /* commit_list borrows our reference, need to remove before we + * clean up our drm_atomic_state. But only after it actually + * completed, otherwise subsequent commits won't stall properly. */ + if (try_wait_for_completion(&commit->flip_done)) + goto del_commit; + + spin_unlock(&crtc->commit_lock); + + /* We must wait for the vblank event to signal our completion + * before releasing our reference, since the vblank work does + * not hold a reference of its own. */ + ret = wait_for_completion_timeout(&commit->flip_done, + 10*HZ); + if (ret == 0) + DRM_ERROR("[CRTC:%d:%s] flip_done timed out\n", + crtc->base.id, crtc->name); + + spin_lock(&crtc->commit_lock); +del_commit: + list_del(&commit->commit_entry); + spin_unlock(&crtc->commit_lock); + } +} +EXPORT_SYMBOL(drm_atomic_helper_commit_cleanup_done); + /** * drm_atomic_helper_prepare_planes - prepare plane resources before commit * @dev: DRM device @@ -1249,16 +1616,12 @@ EXPORT_SYMBOL(drm_atomic_helper_commit); int drm_atomic_helper_prepare_planes(struct drm_device *dev, struct drm_atomic_state *state) { - int nplanes = dev->mode_config.num_total_plane; - int ret, i; + struct drm_plane *plane; + struct drm_plane_state *plane_state; + int ret, i, j; - for (i = 0; i < nplanes; i++) { + for_each_plane_in_state(state, plane, plane_state, i) { const struct drm_plane_helper_funcs *funcs; - struct drm_plane *plane = state->planes[i]; - struct drm_plane_state *plane_state = state->plane_states[i]; - - if (!plane) - continue; funcs = plane->helper_private; @@ -1272,12 +1635,10 @@ int drm_atomic_helper_prepare_planes(struct drm_device *dev, return 0; fail: - for (i--; i >= 0; i--) { + for_each_plane_in_state(state, plane, plane_state, j) { const struct drm_plane_helper_funcs *funcs; - struct drm_plane *plane = state->planes[i]; - struct drm_plane_state *plane_state = state->plane_states[i]; - if (!plane) + if (j >= i) continue; funcs = plane->helper_private; @@ -1537,8 +1898,8 @@ EXPORT_SYMBOL(drm_atomic_helper_cleanup_planes); /** * drm_atomic_helper_swap_state - store atomic state into current sw state - * @dev: DRM device * @state: atomic state + * @stall: stall for proceeding commits * * This function stores the atomic state into the current state pointers in all * driver objects. It should be called after all failing steps have been done @@ -1559,42 +1920,70 @@ EXPORT_SYMBOL(drm_atomic_helper_cleanup_planes); * * 5. Call drm_atomic_helper_cleanup_planes() with @state, which since step 3 * contains the old state. Also do any other cleanup required with that state. + * + * @stall must be set when nonblocking commits for this driver directly access + * the ->state pointer of &drm_plane, &drm_crtc or &drm_connector. With the + * current atomic helpers this is almost always the case, since the helpers + * don't pass the right state structures to the callbacks. */ -void drm_atomic_helper_swap_state(struct drm_device *dev, - struct drm_atomic_state *state) +void drm_atomic_helper_swap_state(struct drm_atomic_state *state, + bool stall) { int i; + long ret; + struct drm_connector *connector; + struct drm_connector_state *conn_state; + struct drm_crtc *crtc; + struct drm_crtc_state *crtc_state; + struct drm_plane *plane; + struct drm_plane_state *plane_state; + struct drm_crtc_commit *commit; + + if (stall) { + for_each_crtc_in_state(state, crtc, crtc_state, i) { + spin_lock(&crtc->commit_lock); + commit = list_first_entry_or_null(&crtc->commit_list, + struct drm_crtc_commit, commit_entry); + if (commit) + drm_crtc_commit_get(commit); + spin_unlock(&crtc->commit_lock); + + if (!commit) + continue; - for (i = 0; i < state->num_connector; i++) { - struct drm_connector *connector = state->connectors[i]; - - if (!connector) - continue; + ret = wait_for_completion_timeout(&commit->hw_done, + 10*HZ); + if (ret == 0) + DRM_ERROR("[CRTC:%d:%s] hw_done timed out\n", + crtc->base.id, crtc->name); + drm_crtc_commit_put(commit); + } + } + for_each_connector_in_state(state, connector, conn_state, i) { connector->state->state = state; - swap(state->connector_states[i], connector->state); + swap(state->connectors[i].state, connector->state); connector->state->state = NULL; } - for (i = 0; i < dev->mode_config.num_crtc; i++) { - struct drm_crtc *crtc = state->crtcs[i]; - - if (!crtc) - continue; - + for_each_crtc_in_state(state, crtc, crtc_state, i) { crtc->state->state = state; - swap(state->crtc_states[i], crtc->state); + swap(state->crtcs[i].state, crtc->state); crtc->state->state = NULL; - } - for (i = 0; i < dev->mode_config.num_total_plane; i++) { - struct drm_plane *plane = state->planes[i]; + if (state->crtcs[i].commit) { + spin_lock(&crtc->commit_lock); + list_add(&state->crtcs[i].commit->commit_entry, + &crtc->commit_list); + spin_unlock(&crtc->commit_lock); - if (!plane) - continue; + state->crtcs[i].commit->event = NULL; + } + } + for_each_plane_in_state(state, plane, plane_state, i) { plane->state->state = state; - swap(state->plane_states[i], plane->state); + swap(state->planes[i].state, plane->state); plane->state->state = NULL; } } @@ -2409,7 +2798,7 @@ EXPORT_SYMBOL(drm_atomic_helper_page_flip); * This is the main helper function provided by the atomic helper framework for * implementing the legacy DPMS connector interface. It computes the new desired * ->active state for the corresponding CRTC (if the connector is enabled) and - * updates it. + * updates it. * * Returns: * Returns 0 on success, negative errno numbers on failure. @@ -2930,16 +3319,15 @@ EXPORT_SYMBOL(drm_atomic_helper_connector_destroy_state); * @red: red correction table * @green: green correction table * @blue: green correction table - * @start: * @size: size of the tables * * Implements support for legacy gamma correction table for drivers * that support color management through the DEGAMMA_LUT/GAMMA_LUT * properties. */ -void drm_atomic_helper_legacy_gamma_set(struct drm_crtc *crtc, - u16 *red, u16 *green, u16 *blue, - uint32_t start, uint32_t size) +int drm_atomic_helper_legacy_gamma_set(struct drm_crtc *crtc, + u16 *red, u16 *green, u16 *blue, + uint32_t size) { struct drm_device *dev = crtc->dev; struct drm_mode_config *config = &dev->mode_config; @@ -2951,7 +3339,7 @@ void drm_atomic_helper_legacy_gamma_set(struct drm_crtc *crtc, state = drm_atomic_state_alloc(crtc->dev); if (!state) - return; + return -ENOMEM; blob = drm_property_create_blob(dev, sizeof(struct drm_color_lut) * size, @@ -3002,7 +3390,7 @@ retry: drm_property_unreference_blob(blob); - return; + return 0; fail: if (ret == -EDEADLK) goto backoff; @@ -3010,7 +3398,7 @@ fail: drm_atomic_state_free(state); drm_property_unreference_blob(blob); - return; + return ret; backoff: drm_atomic_state_clear(state); drm_atomic_legacy_backoff(state); |