/* * Copyright (c) 2006-2008 Intel Corporation * Copyright (c) 2007 Dave Airlie <[email protected]> * * 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 <[email protected]> * Dave Airlie <[email protected]> * Jesse Barnes <[email protected]> */ #include <linux/export.h> #include <linux/moduleparam.h> #include <drm/drm_bridge.h> #include <drm/drm_client.h> #include <drm/drm_crtc.h> #include <drm/drm_edid.h> #include <drm/drm_fourcc.h> #include <drm/drm_managed.h> #include <drm/drm_modeset_helper_vtables.h> #include <drm/drm_print.h> #include <drm/drm_probe_helper.h> #include <drm/drm_sysfs.h> #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 = …; 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) { … } 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) { … } static int drm_helper_probe_add_cmdline_mode(struct drm_connector *connector) { … } enum drm_mode_status drm_crtc_mode_valid(struct drm_crtc *crtc, const struct drm_display_mode *mode) { … } enum drm_mode_status drm_encoder_mode_valid(struct drm_encoder *encoder, const struct drm_display_mode *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) { … } static void drm_kms_helper_disable_hpd(struct drm_device *dev) { … } static bool drm_kms_helper_enable_hpd(struct drm_device *dev) { … } #define DRM_OUTPUT_POLL_PERIOD … static void reschedule_output_poll_work(struct drm_device *dev) { … } /** * 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. * * If device polling was never initialized before, this call will trigger a * warning and return. * * 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) { … } EXPORT_SYMBOL(…); /** * drm_kms_helper_poll_reschedule - reschedule the output polling work * @dev: drm_device * * This function reschedules the output polling work, after polling for a * connector has been enabled. * * Drivers must call this helper after enabling polling for a connector by * setting %DRM_CONNECTOR_POLL_CONNECT / %DRM_CONNECTOR_POLL_DISCONNECT flags * in drm_connector::polled. Note that after disabling polling by clearing these * flags for a connector will stop the output polling work automatically if * the polling is disabled for all other connectors as well. * * The function can be called only after polling has been enabled by calling * drm_kms_helper_poll_init() / drm_kms_helper_poll_enable(). */ void drm_kms_helper_poll_reschedule(struct drm_device *dev) { … } EXPORT_SYMBOL(…); static enum drm_connector_status drm_helper_probe_detect_ctx(struct drm_connector *connector, bool force) { … } /** * 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) { … } EXPORT_SYMBOL(…); static int drm_helper_probe_get_modes(struct drm_connector *connector) { … } static int __drm_helper_update_and_validate(struct drm_connector *connector, uint32_t maxX, uint32_t maxY, struct drm_modeset_acquire_ctx *ctx) { … } /** * 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) { … } EXPORT_SYMBOL(…); /** * 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) { … } EXPORT_SYMBOL(…); /** * 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) { … } EXPORT_SYMBOL(…); static void output_poll_execute(struct work_struct *work) { … } /** * 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) { … } EXPORT_SYMBOL(…); /** * 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(). * * If however, the polling was never initialized, this call will trigger a * warning and return * * 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) { … } EXPORT_SYMBOL(…); /** * 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) { … } EXPORT_SYMBOL(…); /** * 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) { … } EXPORT_SYMBOL(…); static void drm_kms_helper_poll_init_release(struct drm_device *dev, void *res) { … } /** * drmm_kms_helper_poll_init - initialize and enable output polling * @dev: drm_device * * This function initializes and then also enables output polling support for * @dev similar to drm_kms_helper_poll_init(). Polling will automatically be * cleaned up when the DRM device goes away. * * See drm_kms_helper_poll_init() for more information. * * Returns: * 0 on success, or a negative errno code otherwise. */ int drmm_kms_helper_poll_init(struct drm_device *dev) { … } EXPORT_SYMBOL(…); static bool check_connector_changed(struct drm_connector *connector) { … } /** * 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) { … } EXPORT_SYMBOL(…); /** * 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) { … } EXPORT_SYMBOL(…); /** * 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) { … } EXPORT_SYMBOL(…); /** * 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) { … } EXPORT_SYMBOL(…); /** * 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) { … } EXPORT_SYMBOL(…); /** * drm_connector_helper_tv_get_modes - Fills the modes availables to a TV connector * @connector: The connector * * Fills the available modes for a TV connector based on the supported * TV modes, and the default mode expressed by the kernel command line. * * This can be used as the default TV connector helper .get_modes() hook * if the driver does not need any special processing. * * Returns: * The number of modes added to the connector. */ int drm_connector_helper_tv_get_modes(struct drm_connector *connector) { … } EXPORT_SYMBOL(…); /** * drm_connector_helper_detect_from_ddc - Read EDID and detect connector status. * @connector: The connector * @ctx: Acquire context * @force: Perform screen-destructive operations, if necessary * * Detects the connector status by reading the EDID using drm_probe_ddc(), * which requires connector->ddc to be set. Returns connector_status_connected * on success or connector_status_disconnected on failure. * * Returns: * The connector status as defined by enum drm_connector_status. */ int drm_connector_helper_detect_from_ddc(struct drm_connector *connector, struct drm_modeset_acquire_ctx *ctx, bool force) { … } EXPORT_SYMBOL(…);