/* * Copyright (c) 2006-2008 Intel Corporation * Copyright (c) 2007 Dave Airlie * * DRM core CRTC related functions * * Permission to use, copy, modify, distribute, and sell this software and its * documentation for any purpose is hereby granted without fee, provided that * the above copyright notice appear in all copies and that both that copyright * notice and this permission notice appear in supporting documentation, and * that the name of the copyright holders not be used in advertising or * publicity pertaining to distribution of the software without specific, * written prior permission. The copyright holders make no representations * about the suitability of this software for any purpose. It is provided "as * is" without express or implied warranty. * * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE * OF THIS SOFTWARE. * * Authors: * Keith Packard * Eric Anholt * Dave Airlie * Jesse Barnes */ #include #include #include #include #include #include #include #include #include #include #include #include #include "drm_crtc_helper_internal.h" /** * DOC: output probing helper overview * * This library provides some helper code for output probing. It provides an * implementation of the core &drm_connector_funcs.fill_modes interface with * drm_helper_probe_single_connector_modes(). * * It also provides support for polling connectors with a work item and for * generic hotplug interrupt handling where the driver doesn't or cannot keep * track of a per-connector hpd interrupt. * * This helper library can be used independently of the modeset helper library. * Drivers can also overwrite different parts e.g. use their own hotplug * handling code to avoid probing unrelated outputs. * * The probe helpers share the function table structures with other display * helper libraries. See &struct drm_connector_helper_funcs for the details. */ static bool drm_kms_helper_poll = true; module_param_named(poll, drm_kms_helper_poll, bool, 0600); static enum drm_mode_status drm_mode_validate_flag(const struct drm_display_mode *mode, int flags) { if ((mode->flags & DRM_MODE_FLAG_INTERLACE) && !(flags & DRM_MODE_FLAG_INTERLACE)) return MODE_NO_INTERLACE; if ((mode->flags & DRM_MODE_FLAG_DBLSCAN) && !(flags & DRM_MODE_FLAG_DBLSCAN)) return MODE_NO_DBLESCAN; if ((mode->flags & DRM_MODE_FLAG_3D_MASK) && !(flags & DRM_MODE_FLAG_3D_MASK)) return MODE_NO_STEREO; return MODE_OK; } static int drm_mode_validate_pipeline(struct drm_display_mode *mode, struct drm_connector *connector, struct drm_modeset_acquire_ctx *ctx, enum drm_mode_status *status) { struct drm_device *dev = connector->dev; struct drm_encoder *encoder; int ret; /* Step 1: Validate against connector */ ret = drm_connector_mode_valid(connector, mode, ctx, status); if (ret || *status != MODE_OK) return ret; /* Step 2: Validate against encoders and crtcs */ drm_connector_for_each_possible_encoder(connector, encoder) { struct drm_bridge *bridge; struct drm_crtc *crtc; *status = drm_encoder_mode_valid(encoder, mode); if (*status != MODE_OK) { /* No point in continuing for crtc check as this encoder * will not accept the mode anyway. If all encoders * reject the mode then, at exit, ret will not be * MODE_OK. */ continue; } bridge = drm_bridge_chain_get_first_bridge(encoder); *status = drm_bridge_chain_mode_valid(bridge, &connector->display_info, mode); if (*status != MODE_OK) { /* There is also no point in continuing for crtc check * here. */ continue; } drm_for_each_crtc(crtc, dev) { if (!drm_encoder_crtc_ok(encoder, crtc)) continue; *status = drm_crtc_mode_valid(crtc, mode); if (*status == MODE_OK) { /* If we get to this point there is at least * one combination of encoder+crtc that works * for this mode. Lets return now. */ return 0; } } } return 0; } static int drm_helper_probe_add_cmdline_mode(struct drm_connector *connector) { struct drm_cmdline_mode *cmdline_mode; struct drm_display_mode *mode; cmdline_mode = &connector->cmdline_mode; if (!cmdline_mode->specified) return 0; /* Only add a GTF mode if we find no matching probed modes */ list_for_each_entry(mode, &connector->probed_modes, head) { if (mode->hdisplay != cmdline_mode->xres || mode->vdisplay != cmdline_mode->yres) continue; if (cmdline_mode->refresh_specified) { /* The probed mode's vrefresh is set until later */ if (drm_mode_vrefresh(mode) != cmdline_mode->refresh) continue; } /* Mark the matching mode as being preferred by the user */ mode->type |= DRM_MODE_TYPE_USERDEF; return 0; } mode = drm_mode_create_from_cmdline_mode(connector->dev, cmdline_mode); if (mode == NULL) return 0; drm_mode_probed_add(connector, mode); return 1; } enum drm_mode_status drm_crtc_mode_valid(struct drm_crtc *crtc, const struct drm_display_mode *mode) { const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private; if (!crtc_funcs || !crtc_funcs->mode_valid) return MODE_OK; return crtc_funcs->mode_valid(crtc, mode); } enum drm_mode_status drm_encoder_mode_valid(struct drm_encoder *encoder, const struct drm_display_mode *mode) { const struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private; if (!encoder_funcs || !encoder_funcs->mode_valid) return MODE_OK; return encoder_funcs->mode_valid(encoder, mode); } int drm_connector_mode_valid(struct drm_connector *connector, struct drm_display_mode *mode, struct drm_modeset_acquire_ctx *ctx, enum drm_mode_status *status) { const struct drm_connector_helper_funcs *connector_funcs = connector->helper_private; int ret = 0; if (!connector_funcs) *status = MODE_OK; else if (connector_funcs->mode_valid_ctx) ret = connector_funcs->mode_valid_ctx(connector, mode, ctx, status); else if (connector_funcs->mode_valid) *status = connector_funcs->mode_valid(connector, mode); else *status = MODE_OK; return ret; } #define DRM_OUTPUT_POLL_PERIOD (10*HZ) /** * drm_kms_helper_poll_enable - re-enable output polling. * @dev: drm_device * * This function re-enables the output polling work, after it has been * temporarily disabled using drm_kms_helper_poll_disable(), for example over * suspend/resume. * * Drivers can call this helper from their device resume implementation. It is * not an error to call this even when output polling isn't enabled. * * Note that calls to enable and disable polling must be strictly ordered, which * is automatically the case when they're only call from suspend/resume * callbacks. */ void drm_kms_helper_poll_enable(struct drm_device *dev) { bool poll = false; struct drm_connector *connector; struct drm_connector_list_iter conn_iter; unsigned long delay = DRM_OUTPUT_POLL_PERIOD; if (!dev->mode_config.poll_enabled || !drm_kms_helper_poll) return; drm_connector_list_iter_begin(dev, &conn_iter); drm_for_each_connector_iter(connector, &conn_iter) { if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT)) poll = true; } drm_connector_list_iter_end(&conn_iter); if (dev->mode_config.delayed_event) { /* * FIXME: * * Use short (1s) delay to handle the initial delayed event. * This delay should not be needed, but Optimus/nouveau will * fail in a mysterious way if the delayed event is handled as * soon as possible like it is done in * drm_helper_probe_single_connector_modes() in case the poll * was enabled before. */ poll = true; delay = HZ; } if (poll) schedule_delayed_work(&dev->mode_config.output_poll_work, delay); } EXPORT_SYMBOL(drm_kms_helper_poll_enable); static enum drm_connector_status drm_helper_probe_detect_ctx(struct drm_connector *connector, bool force) { const struct drm_connector_helper_funcs *funcs = connector->helper_private; struct drm_modeset_acquire_ctx ctx; int ret; drm_modeset_acquire_init(&ctx, 0); retry: ret = drm_modeset_lock(&connector->dev->mode_config.connection_mutex, &ctx); if (!ret) { if (funcs->detect_ctx) ret = funcs->detect_ctx(connector, &ctx, force); else if (connector->funcs->detect) ret = connector->funcs->detect(connector, force); else ret = connector_status_connected; } if (ret == -EDEADLK) { drm_modeset_backoff(&ctx); goto retry; } if (WARN_ON(ret < 0)) ret = connector_status_unknown; if (ret != connector->status) connector->epoch_counter += 1; drm_modeset_drop_locks(&ctx); drm_modeset_acquire_fini(&ctx); return ret; } /** * drm_helper_probe_detect - probe connector status * @connector: connector to probe * @ctx: acquire_ctx, or NULL to let this function handle locking. * @force: Whether destructive probe operations should be performed. * * This function calls the detect callbacks of the connector. * This function returns &drm_connector_status, or * if @ctx is set, it might also return -EDEADLK. */ int drm_helper_probe_detect(struct drm_connector *connector, struct drm_modeset_acquire_ctx *ctx, bool force) { const struct drm_connector_helper_funcs *funcs = connector->helper_private; struct drm_device *dev = connector->dev; int ret; if (!ctx) return drm_helper_probe_detect_ctx(connector, force); ret = drm_modeset_lock(&dev->mode_config.connection_mutex, ctx); if (ret) return ret; if (funcs->detect_ctx) ret = funcs->detect_ctx(connector, ctx, force); else if (connector->funcs->detect) ret = connector->funcs->detect(connector, force); else ret = connector_status_connected; if (ret != connector->status) connector->epoch_counter += 1; return ret; } EXPORT_SYMBOL(drm_helper_probe_detect); static int drm_helper_probe_get_modes(struct drm_connector *connector) { const struct drm_connector_helper_funcs *connector_funcs = connector->helper_private; int count; count = connector_funcs->get_modes(connector); /* The .get_modes() callback should not return negative values. */ if (count < 0) { drm_err(connector->dev, ".get_modes() returned %pe\n", ERR_PTR(count)); count = 0; } /* * Fallback for when DDC probe failed in drm_get_edid() and thus skipped * override/firmware EDID. */ if (count == 0 && connector->status == connector_status_connected) count = drm_add_override_edid_modes(connector); return count; } static int __drm_helper_update_and_validate(struct drm_connector *connector, uint32_t maxX, uint32_t maxY, struct drm_modeset_acquire_ctx *ctx) { struct drm_device *dev = connector->dev; struct drm_display_mode *mode; int mode_flags = 0; int ret; drm_connector_list_update(connector); if (connector->interlace_allowed) mode_flags |= DRM_MODE_FLAG_INTERLACE; if (connector->doublescan_allowed) mode_flags |= DRM_MODE_FLAG_DBLSCAN; if (connector->stereo_allowed) mode_flags |= DRM_MODE_FLAG_3D_MASK; list_for_each_entry(mode, &connector->modes, head) { if (mode->status != MODE_OK) continue; mode->status = drm_mode_validate_driver(dev, mode); if (mode->status != MODE_OK) continue; mode->status = drm_mode_validate_size(mode, maxX, maxY); if (mode->status != MODE_OK) continue; mode->status = drm_mode_validate_flag(mode, mode_flags); if (mode->status != MODE_OK) continue; ret = drm_mode_validate_pipeline(mode, connector, ctx, &mode->status); if (ret) { drm_dbg_kms(dev, "drm_mode_validate_pipeline failed: %d\n", ret); if (drm_WARN_ON_ONCE(dev, ret != -EDEADLK)) mode->status = MODE_ERROR; else return -EDEADLK; } if (mode->status != MODE_OK) continue; mode->status = drm_mode_validate_ycbcr420(mode, connector); } return 0; } /** * drm_helper_probe_single_connector_modes - get complete set of display modes * @connector: connector to probe * @maxX: max width for modes * @maxY: max height for modes * * Based on the helper callbacks implemented by @connector in struct * &drm_connector_helper_funcs try to detect all valid modes. Modes will first * be added to the connector's probed_modes list, then culled (based on validity * and the @maxX, @maxY parameters) and put into the normal modes list. * * Intended to be used as a generic implementation of the * &drm_connector_funcs.fill_modes() vfunc for drivers that use the CRTC helpers * for output mode filtering and detection. * * The basic procedure is as follows * * 1. All modes currently on the connector's modes list are marked as stale * * 2. New modes are added to the connector's probed_modes list with * drm_mode_probed_add(). New modes start their life with status as OK. * Modes are added from a single source using the following priority order. * * - &drm_connector_helper_funcs.get_modes vfunc * - if the connector status is connector_status_connected, standard * VESA DMT modes up to 1024x768 are automatically added * (drm_add_modes_noedid()) * * Finally modes specified via the kernel command line (video=...) are * added in addition to what the earlier probes produced * (drm_helper_probe_add_cmdline_mode()). These modes are generated * using the VESA GTF/CVT formulas. * * 3. Modes are moved from the probed_modes list to the modes list. Potential * duplicates are merged together (see drm_connector_list_update()). * After this step the probed_modes list will be empty again. * * 4. Any non-stale mode on the modes list then undergoes validation * * - drm_mode_validate_basic() performs basic sanity checks * - drm_mode_validate_size() filters out modes larger than @maxX and @maxY * (if specified) * - drm_mode_validate_flag() checks the modes against basic connector * capabilities (interlace_allowed,doublescan_allowed,stereo_allowed) * - the optional &drm_connector_helper_funcs.mode_valid or * &drm_connector_helper_funcs.mode_valid_ctx helpers can perform driver * and/or sink specific checks * - the optional &drm_crtc_helper_funcs.mode_valid, * &drm_bridge_funcs.mode_valid and &drm_encoder_helper_funcs.mode_valid * helpers can perform driver and/or source specific checks which are also * enforced by the modeset/atomic helpers * * 5. Any mode whose status is not OK is pruned from the connector's modes list, * accompanied by a debug message indicating the reason for the mode's * rejection (see drm_mode_prune_invalid()). * * Returns: * The number of modes found on @connector. */ int drm_helper_probe_single_connector_modes(struct drm_connector *connector, uint32_t maxX, uint32_t maxY) { struct drm_device *dev = connector->dev; struct drm_display_mode *mode; int count = 0, ret; enum drm_connector_status old_status; struct drm_modeset_acquire_ctx ctx; WARN_ON(!mutex_is_locked(&dev->mode_config.mutex)); drm_modeset_acquire_init(&ctx, 0); DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n", connector->base.id, connector->name); retry: ret = drm_modeset_lock(&dev->mode_config.connection_mutex, &ctx); if (ret == -EDEADLK) { drm_modeset_backoff(&ctx); goto retry; } else WARN_ON(ret < 0); /* set all old modes to the stale state */ list_for_each_entry(mode, &connector->modes, head) mode->status = MODE_STALE; old_status = connector->status; if (connector->force) { if (connector->force == DRM_FORCE_ON || connector->force == DRM_FORCE_ON_DIGITAL) connector->status = connector_status_connected; else connector->status = connector_status_disconnected; if (connector->funcs->force) connector->funcs->force(connector); } else { ret = drm_helper_probe_detect(connector, &ctx, true); if (ret == -EDEADLK) { drm_modeset_backoff(&ctx); goto retry; } else if (WARN(ret < 0, "Invalid return value %i for connector detection\n", ret)) ret = connector_status_unknown; connector->status = ret; } /* * Normally either the driver's hpd code or the poll loop should * pick up any changes and fire the hotplug event. But if * userspace sneaks in a probe, we might miss a change. Hence * check here, and if anything changed start the hotplug code. */ if (old_status != connector->status) { DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n", connector->base.id, connector->name, drm_get_connector_status_name(old_status), drm_get_connector_status_name(connector->status)); /* * The hotplug event code might call into the fb * helpers, and so expects that we do not hold any * locks. Fire up the poll struct instead, it will * disable itself again. */ dev->mode_config.delayed_event = true; if (dev->mode_config.poll_enabled) mod_delayed_work(system_wq, &dev->mode_config.output_poll_work, 0); } /* Re-enable polling in case the global poll config changed. */ if (drm_kms_helper_poll != dev->mode_config.poll_running) drm_kms_helper_poll_enable(dev); dev->mode_config.poll_running = drm_kms_helper_poll; if (connector->status == connector_status_disconnected) { DRM_DEBUG_KMS("[CONNECTOR:%d:%s] disconnected\n", connector->base.id, connector->name); drm_connector_update_edid_property(connector, NULL); drm_mode_prune_invalid(dev, &connector->modes, false); goto exit; } count = drm_helper_probe_get_modes(connector); if (count == 0 && (connector->status == connector_status_connected || connector->status == connector_status_unknown)) { count = drm_add_modes_noedid(connector, 1024, 768); /* * Section 4.2.2.6 (EDID Corruption Detection) of the DP 1.4a * Link CTS specifies that 640x480 (the official "failsafe" * mode) needs to be the default if there's no EDID. */ if (connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort) drm_set_preferred_mode(connector, 640, 480); } count += drm_helper_probe_add_cmdline_mode(connector); if (count != 0) { ret = __drm_helper_update_and_validate(connector, maxX, maxY, &ctx); if (ret == -EDEADLK) { drm_modeset_backoff(&ctx); goto retry; } } drm_mode_prune_invalid(dev, &connector->modes, true); /* * Displayport spec section 5.2.1.2 ("Video Timing Format") says that * all detachable sinks shall support 640x480 @60Hz as a fail safe * mode. If all modes were pruned, perhaps because they need more * lanes or a higher pixel clock than available, at least try to add * in 640x480. */ if (list_empty(&connector->modes) && connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort) { count = drm_add_modes_noedid(connector, 640, 480); ret = __drm_helper_update_and_validate(connector, maxX, maxY, &ctx); if (ret == -EDEADLK) { drm_modeset_backoff(&ctx); goto retry; } drm_mode_prune_invalid(dev, &connector->modes, true); } exit: drm_modeset_drop_locks(&ctx); drm_modeset_acquire_fini(&ctx); if (list_empty(&connector->modes)) return 0; drm_mode_sort(&connector->modes); DRM_DEBUG_KMS("[CONNECTOR:%d:%s] probed modes :\n", connector->base.id, connector->name); list_for_each_entry(mode, &connector->modes, head) { drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V); drm_mode_debug_printmodeline(mode); } return count; } EXPORT_SYMBOL(drm_helper_probe_single_connector_modes); /** * drm_kms_helper_hotplug_event - fire off KMS hotplug events * @dev: drm_device whose connector state changed * * This function fires off the uevent for userspace and also calls the * output_poll_changed function, which is most commonly used to inform the fbdev * emulation code and allow it to update the fbcon output configuration. * * Drivers should call this from their hotplug handling code when a change is * detected. Note that this function does not do any output detection of its * own, like drm_helper_hpd_irq_event() does - this is assumed to be done by the * driver already. * * This function must be called from process context with no mode * setting locks held. * * If only a single connector has changed, consider calling * drm_kms_helper_connector_hotplug_event() instead. */ void drm_kms_helper_hotplug_event(struct drm_device *dev) { /* send a uevent + call fbdev */ drm_sysfs_hotplug_event(dev); if (dev->mode_config.funcs->output_poll_changed) dev->mode_config.funcs->output_poll_changed(dev); drm_client_dev_hotplug(dev); } EXPORT_SYMBOL(drm_kms_helper_hotplug_event); /** * drm_kms_helper_connector_hotplug_event - fire off a KMS connector hotplug event * @connector: drm_connector which has changed * * This is the same as drm_kms_helper_hotplug_event(), except it fires a more * fine-grained uevent for a single connector. */ void drm_kms_helper_connector_hotplug_event(struct drm_connector *connector) { struct drm_device *dev = connector->dev; /* send a uevent + call fbdev */ drm_sysfs_connector_hotplug_event(connector); if (dev->mode_config.funcs->output_poll_changed) dev->mode_config.funcs->output_poll_changed(dev); drm_client_dev_hotplug(dev); } EXPORT_SYMBOL(drm_kms_helper_connector_hotplug_event); static void output_poll_execute(struct work_struct *work) { struct delayed_work *delayed_work = to_delayed_work(work); struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_work); struct drm_connector *connector; struct drm_connector_list_iter conn_iter; enum drm_connector_status old_status; bool repoll = false, changed; u64 old_epoch_counter; if (!dev->mode_config.poll_enabled) return; /* Pick up any changes detected by the probe functions. */ changed = dev->mode_config.delayed_event; dev->mode_config.delayed_event = false; if (!drm_kms_helper_poll) goto out; if (!mutex_trylock(&dev->mode_config.mutex)) { repoll = true; goto out; } drm_connector_list_iter_begin(dev, &conn_iter); drm_for_each_connector_iter(connector, &conn_iter) { /* Ignore forced connectors. */ if (connector->force) continue; /* Ignore HPD capable connectors and connectors where we don't * want any hotplug detection at all for polling. */ if (!connector->polled || connector->polled == DRM_CONNECTOR_POLL_HPD) continue; old_status = connector->status; /* if we are connected and don't want to poll for disconnect skip it */ if (old_status == connector_status_connected && !(connector->polled & DRM_CONNECTOR_POLL_DISCONNECT)) continue; repoll = true; old_epoch_counter = connector->epoch_counter; connector->status = drm_helper_probe_detect(connector, NULL, false); if (old_epoch_counter != connector->epoch_counter) { const char *old, *new; /* * The poll work sets force=false when calling detect so * that drivers can avoid to do disruptive tests (e.g. * when load detect cycles could cause flickering on * other, running displays). This bears the risk that we * flip-flop between unknown here in the poll work and * the real state when userspace forces a full detect * call after receiving a hotplug event due to this * change. * * Hence clamp an unknown detect status to the old * value. */ if (connector->status == connector_status_unknown) { connector->status = old_status; continue; } old = drm_get_connector_status_name(old_status); new = drm_get_connector_status_name(connector->status); DRM_DEBUG_KMS("[CONNECTOR:%d:%s] " "status updated from %s to %s\n", connector->base.id, connector->name, old, new); DRM_DEBUG_KMS("[CONNECTOR:%d:%s] epoch counter %llu -> %llu\n", connector->base.id, connector->name, old_epoch_counter, connector->epoch_counter); changed = true; } } drm_connector_list_iter_end(&conn_iter); mutex_unlock(&dev->mode_config.mutex); out: if (changed) drm_kms_helper_hotplug_event(dev); if (repoll) schedule_delayed_work(delayed_work, DRM_OUTPUT_POLL_PERIOD); } /** * drm_kms_helper_is_poll_worker - is %current task an output poll worker? * * Determine if %current task is an output poll worker. This can be used * to select distinct code paths for output polling versus other contexts. * * One use case is to avoid a deadlock between the output poll worker and * the autosuspend worker wherein the latter waits for polling to finish * upon calling drm_kms_helper_poll_disable(), while the former waits for * runtime suspend to finish upon calling pm_runtime_get_sync() in a * connector ->detect hook. */ bool drm_kms_helper_is_poll_worker(void) { struct work_struct *work = current_work(); return work && work->func == output_poll_execute; } EXPORT_SYMBOL(drm_kms_helper_is_poll_worker); /** * drm_kms_helper_poll_disable - disable output polling * @dev: drm_device * * This function disables the output polling work. * * Drivers can call this helper from their device suspend implementation. It is * not an error to call this even when output polling isn't enabled or already * disabled. Polling is re-enabled by calling drm_kms_helper_poll_enable(). * * Note that calls to enable and disable polling must be strictly ordered, which * is automatically the case when they're only call from suspend/resume * callbacks. */ void drm_kms_helper_poll_disable(struct drm_device *dev) { if (!dev->mode_config.poll_enabled) return; cancel_delayed_work_sync(&dev->mode_config.output_poll_work); } EXPORT_SYMBOL(drm_kms_helper_poll_disable); /** * drm_kms_helper_poll_init - initialize and enable output polling * @dev: drm_device * * This function initializes and then also enables output polling support for * @dev. Drivers which do not have reliable hotplug support in hardware can use * this helper infrastructure to regularly poll such connectors for changes in * their connection state. * * Drivers can control which connectors are polled by setting the * DRM_CONNECTOR_POLL_CONNECT and DRM_CONNECTOR_POLL_DISCONNECT flags. On * connectors where probing live outputs can result in visual distortion drivers * should not set the DRM_CONNECTOR_POLL_DISCONNECT flag to avoid this. * Connectors which have no flag or only DRM_CONNECTOR_POLL_HPD set are * completely ignored by the polling logic. * * Note that a connector can be both polled and probed from the hotplug handler, * in case the hotplug interrupt is known to be unreliable. */ void drm_kms_helper_poll_init(struct drm_device *dev) { INIT_DELAYED_WORK(&dev->mode_config.output_poll_work, output_poll_execute); dev->mode_config.poll_enabled = true; drm_kms_helper_poll_enable(dev); } EXPORT_SYMBOL(drm_kms_helper_poll_init); /** * drm_kms_helper_poll_fini - disable output polling and clean it up * @dev: drm_device */ void drm_kms_helper_poll_fini(struct drm_device *dev) { if (!dev->mode_config.poll_enabled) return; dev->mode_config.poll_enabled = false; cancel_delayed_work_sync(&dev->mode_config.output_poll_work); } EXPORT_SYMBOL(drm_kms_helper_poll_fini); static bool check_connector_changed(struct drm_connector *connector) { struct drm_device *dev = connector->dev; enum drm_connector_status old_status; u64 old_epoch_counter; /* Only handle HPD capable connectors. */ drm_WARN_ON(dev, !(connector->polled & DRM_CONNECTOR_POLL_HPD)); drm_WARN_ON(dev, !mutex_is_locked(&dev->mode_config.mutex)); old_status = connector->status; old_epoch_counter = connector->epoch_counter; connector->status = drm_helper_probe_detect(connector, NULL, false); if (old_epoch_counter == connector->epoch_counter) { drm_dbg_kms(dev, "[CONNECTOR:%d:%s] Same epoch counter %llu\n", connector->base.id, connector->name, connector->epoch_counter); return false; } drm_dbg_kms(dev, "[CONNECTOR:%d:%s] status updated from %s to %s\n", connector->base.id, connector->name, drm_get_connector_status_name(old_status), drm_get_connector_status_name(connector->status)); drm_dbg_kms(dev, "[CONNECTOR:%d:%s] Changed epoch counter %llu => %llu\n", connector->base.id, connector->name, old_epoch_counter, connector->epoch_counter); return true; } /** * drm_connector_helper_hpd_irq_event - hotplug processing * @connector: drm_connector * * Drivers can use this helper function to run a detect cycle on a connector * which has the DRM_CONNECTOR_POLL_HPD flag set in its &polled member. * * This helper function is useful for drivers which can track hotplug * interrupts for a single connector. Drivers that want to send a * hotplug event for all connectors or can't track hotplug interrupts * per connector need to use drm_helper_hpd_irq_event(). * * This function must be called from process context with no mode * setting locks held. * * Note that a connector can be both polled and probed from the hotplug * handler, in case the hotplug interrupt is known to be unreliable. * * Returns: * A boolean indicating whether the connector status changed or not */ bool drm_connector_helper_hpd_irq_event(struct drm_connector *connector) { struct drm_device *dev = connector->dev; bool changed; mutex_lock(&dev->mode_config.mutex); changed = check_connector_changed(connector); mutex_unlock(&dev->mode_config.mutex); if (changed) { drm_kms_helper_connector_hotplug_event(connector); drm_dbg_kms(dev, "[CONNECTOR:%d:%s] Sent hotplug event\n", connector->base.id, connector->name); } return changed; } EXPORT_SYMBOL(drm_connector_helper_hpd_irq_event); /** * drm_helper_hpd_irq_event - hotplug processing * @dev: drm_device * * Drivers can use this helper function to run a detect cycle on all connectors * which have the DRM_CONNECTOR_POLL_HPD flag set in their &polled member. All * other connectors are ignored, which is useful to avoid reprobing fixed * panels. * * This helper function is useful for drivers which can't or don't track hotplug * interrupts for each connector. * * Drivers which support hotplug interrupts for each connector individually and * which have a more fine-grained detect logic can use * drm_connector_helper_hpd_irq_event(). Alternatively, they should bypass this * code and directly call drm_kms_helper_hotplug_event() in case the connector * state changed. * * This function must be called from process context with no mode * setting locks held. * * Note that a connector can be both polled and probed from the hotplug handler, * in case the hotplug interrupt is known to be unreliable. * * Returns: * A boolean indicating whether the connector status changed or not */ bool drm_helper_hpd_irq_event(struct drm_device *dev) { struct drm_connector *connector, *first_changed_connector = NULL; struct drm_connector_list_iter conn_iter; int changed = 0; if (!dev->mode_config.poll_enabled) return false; mutex_lock(&dev->mode_config.mutex); drm_connector_list_iter_begin(dev, &conn_iter); drm_for_each_connector_iter(connector, &conn_iter) { /* Only handle HPD capable connectors. */ if (!(connector->polled & DRM_CONNECTOR_POLL_HPD)) continue; if (check_connector_changed(connector)) { if (!first_changed_connector) { drm_connector_get(connector); first_changed_connector = connector; } changed++; } } drm_connector_list_iter_end(&conn_iter); mutex_unlock(&dev->mode_config.mutex); if (changed == 1) drm_kms_helper_connector_hotplug_event(first_changed_connector); else if (changed > 0) drm_kms_helper_hotplug_event(dev); if (first_changed_connector) drm_connector_put(first_changed_connector); return changed; } EXPORT_SYMBOL(drm_helper_hpd_irq_event); /** * drm_crtc_helper_mode_valid_fixed - Validates a display mode * @crtc: the crtc * @mode: the mode to validate * @fixed_mode: the display hardware's mode * * Returns: * MODE_OK on success, or another mode-status code otherwise. */ enum drm_mode_status drm_crtc_helper_mode_valid_fixed(struct drm_crtc *crtc, const struct drm_display_mode *mode, const struct drm_display_mode *fixed_mode) { if (mode->hdisplay != fixed_mode->hdisplay && mode->vdisplay != fixed_mode->vdisplay) return MODE_ONE_SIZE; else if (mode->hdisplay != fixed_mode->hdisplay) return MODE_ONE_WIDTH; else if (mode->vdisplay != fixed_mode->vdisplay) return MODE_ONE_HEIGHT; return MODE_OK; } EXPORT_SYMBOL(drm_crtc_helper_mode_valid_fixed); /** * drm_connector_helper_get_modes_from_ddc - Updates the connector's EDID * property from the connector's * DDC channel * @connector: The connector * * Returns: * The number of detected display modes. * * Uses a connector's DDC channel to retrieve EDID data and update the * connector's EDID property and display modes. Drivers can use this * function to implement struct &drm_connector_helper_funcs.get_modes * for connectors with a DDC channel. */ int drm_connector_helper_get_modes_from_ddc(struct drm_connector *connector) { struct edid *edid; int count = 0; if (!connector->ddc) return 0; edid = drm_get_edid(connector, connector->ddc); // clears property if EDID is NULL drm_connector_update_edid_property(connector, edid); if (edid) { count = drm_add_edid_modes(connector, edid); kfree(edid); } return count; } EXPORT_SYMBOL(drm_connector_helper_get_modes_from_ddc); /** * drm_connector_helper_get_modes_fixed - Duplicates a display mode for a connector * @connector: the connector * @fixed_mode: the display hardware's mode * * This function duplicates a display modes for a connector. Drivers for hardware * that only supports a single fixed mode can use this function in their connector's * get_modes helper. * * Returns: * The number of created modes. */ int drm_connector_helper_get_modes_fixed(struct drm_connector *connector, const struct drm_display_mode *fixed_mode) { struct drm_device *dev = connector->dev; struct drm_display_mode *mode; mode = drm_mode_duplicate(dev, fixed_mode); if (!mode) { drm_err(dev, "Failed to duplicate mode " DRM_MODE_FMT "\n", DRM_MODE_ARG(fixed_mode)); return 0; } if (mode->name[0] == '\0') drm_mode_set_name(mode); mode->type |= DRM_MODE_TYPE_PREFERRED; drm_mode_probed_add(connector, mode); if (mode->width_mm) connector->display_info.width_mm = mode->width_mm; if (mode->height_mm) connector->display_info.height_mm = mode->height_mm; return 1; } EXPORT_SYMBOL(drm_connector_helper_get_modes_fixed); /** * drm_connector_helper_get_modes - Read EDID and update connector. * @connector: The connector * * Read the EDID using drm_edid_read() (which requires that connector->ddc is * set), and update the connector using the EDID. * * This can be used as the "default" connector helper .get_modes() hook if the * driver does not need any special processing. This is sets the example what * custom .get_modes() hooks should do regarding EDID read and connector update. * * Returns: Number of modes. */ int drm_connector_helper_get_modes(struct drm_connector *connector) { const struct drm_edid *drm_edid; int count; drm_edid = drm_edid_read(connector); /* * Unconditionally update the connector. If the EDID was read * successfully, fill in the connector information derived from the * EDID. Otherwise, if the EDID is NULL, clear the connector * information. */ count = drm_edid_connector_update(connector, drm_edid); drm_edid_free(drm_edid); return count; } EXPORT_SYMBOL(drm_connector_helper_get_modes);