/* * Copyright (C) 2013, NVIDIA Corporation. All rights reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sub license, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice (including the * next paragraph) shall be included in all copies or substantial portions * of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * DEALINGS IN THE SOFTWARE. */ #ifndef __DRM_PANEL_H__ #define __DRM_PANEL_H__ #include <linux/err.h> #include <linux/errno.h> #include <linux/list.h> #include <linux/mutex.h> #include <linux/kref.h> struct backlight_device; struct dentry; struct device_node; struct drm_connector; struct drm_panel_follower; struct drm_panel; struct display_timing; enum drm_panel_orientation; /** * struct drm_panel_funcs - perform operations on a given panel * * The .prepare() function is typically called before the display controller * starts to transmit video data. Panel drivers can use this to turn the panel * on and wait for it to become ready. If additional configuration is required * (via a control bus such as I2C, SPI or DSI for example) this is a good time * to do that. * * After the display controller has started transmitting video data, it's safe * to call the .enable() function. This will typically enable the backlight to * make the image on screen visible. Some panels require a certain amount of * time or frames before the image is displayed. This function is responsible * for taking this into account before enabling the backlight to avoid visual * glitches. * * Before stopping video transmission from the display controller it can be * necessary to turn off the panel to avoid visual glitches. This is done in * the .disable() function. Analogously to .enable() this typically involves * turning off the backlight and waiting for some time to make sure no image * is visible on the panel. It is then safe for the display controller to * cease transmission of video data. * * To save power when no video data is transmitted, a driver can power down * the panel. This is the job of the .unprepare() function. * * Backlight can be handled automatically if configured using * drm_panel_of_backlight() or drm_panel_dp_aux_backlight(). Then the driver * does not need to implement the functionality to enable/disable backlight. */ struct drm_panel_funcs { /** * @prepare: * * Turn on panel and perform set up. * * This function is optional. */ int (*prepare)(struct drm_panel *panel); /** * @enable: * * Enable panel (turn on back light, etc.). * * This function is optional. */ int (*enable)(struct drm_panel *panel); /** * @disable: * * Disable panel (turn off back light, etc.). * * This function is optional. */ int (*disable)(struct drm_panel *panel); /** * @unprepare: * * Turn off panel. * * This function is optional. */ int (*unprepare)(struct drm_panel *panel); /** * @get_modes: * * Add modes to the connector that the panel is attached to * and returns the number of modes added. * * This function is mandatory. */ int (*get_modes)(struct drm_panel *panel, struct drm_connector *connector); /** * @get_orientation: * * Return the panel orientation set by device tree or EDID. * * This function is optional. */ enum drm_panel_orientation (*get_orientation)(struct drm_panel *panel); /** * @get_timings: * * Copy display timings into the provided array and return * the number of display timings available. * * This function is optional. */ int (*get_timings)(struct drm_panel *panel, unsigned int num_timings, struct display_timing *timings); /** * @debugfs_init: * * Allows panels to create panels-specific debugfs files. */ void (*debugfs_init)(struct drm_panel *panel, struct dentry *root); }; struct drm_panel_follower_funcs { /** * @panel_prepared: * * Called after the panel has been powered on. */ int (*panel_prepared)(struct drm_panel_follower *follower); /** * @panel_unpreparing: * * Called before the panel is powered off. */ int (*panel_unpreparing)(struct drm_panel_follower *follower); /** * @panel_enabled: * * Called after the panel and the backlight have been enabled. */ int (*panel_enabled)(struct drm_panel_follower *follower); /** * @panel_disabling: * * Called before the panel and the backlight are disabled. */ int (*panel_disabling)(struct drm_panel_follower *follower); }; struct drm_panel_follower { /** * @funcs: * * Dependent device callbacks; should be initted by the caller. */ const struct drm_panel_follower_funcs *funcs; /** * @list * * Used for linking into panel's list; set by drm_panel_add_follower(). */ struct list_head list; /** * @panel * * The panel we're dependent on; set by drm_panel_add_follower(). */ struct drm_panel *panel; }; /** * struct drm_panel - DRM panel object */ struct drm_panel { /** * @dev: * * Parent device of the panel. */ struct device *dev; /** * @backlight: * * Backlight device, used to turn on backlight after the call * to enable(), and to turn off backlight before the call to * disable(). * backlight is set by drm_panel_of_backlight() or * drm_panel_dp_aux_backlight() and drivers shall not assign it. */ struct backlight_device *backlight; /** * @funcs: * * Operations that can be performed on the panel. */ const struct drm_panel_funcs *funcs; /** * @connector_type: * * Type of the panel as a DRM_MODE_CONNECTOR_* value. This is used to * initialise the drm_connector corresponding to the panel with the * correct connector type. */ int connector_type; /** * @list: * * Panel entry in registry. */ struct list_head list; /** * @followers: * * A list of struct drm_panel_follower dependent on this panel. */ struct list_head followers; /** * @follower_lock: * * Lock for followers list. */ struct mutex follower_lock; /** * @prepare_prev_first: * * The previous controller should be prepared first, before the prepare * for the panel is called. This is largely required for DSI panels * where the DSI host controller should be initialised to LP-11 before * the panel is powered up. */ bool prepare_prev_first; /** * @prepared: * * If true then the panel has been prepared. */ bool prepared; /** * @enabled: * * If true then the panel has been enabled. */ bool enabled; /** * @container: Pointer to the private driver struct embedding this * @struct drm_panel. */ void *container; /** * @refcount: reference count of users referencing this panel. */ struct kref refcount; }; void *__devm_drm_panel_alloc(struct device *dev, size_t size, size_t offset, const struct drm_panel_funcs *funcs, int connector_type); /** * devm_drm_panel_alloc - Allocate and initialize a refcounted panel. * * @dev: struct device of the panel device * @type: the type of the struct which contains struct &drm_panel * @member: the name of the &drm_panel within @type * @funcs: callbacks for this panel * @connector_type: the connector type (DRM_MODE_CONNECTOR_*) corresponding to * the panel interface * * The reference count of the returned panel is initialized to 1. This * reference will be automatically dropped via devm (by calling * drm_panel_put()) when @dev is removed. * * Returns: * Pointer to container structure embedding the panel, ERR_PTR on failure. */ #define devm_drm_panel_alloc(dev, type, member, funcs, connector_type) \ ((type *)__devm_drm_panel_alloc(dev, sizeof(type), \ offsetof(type, member), funcs, \ connector_type)) void drm_panel_init(struct drm_panel *panel, struct device *dev, const struct drm_panel_funcs *funcs, int connector_type); struct drm_panel *drm_panel_get(struct drm_panel *panel); void drm_panel_put(struct drm_panel *panel); void drm_panel_add(struct drm_panel *panel); void drm_panel_remove(struct drm_panel *panel); void drm_panel_prepare(struct drm_panel *panel); void drm_panel_unprepare(struct drm_panel *panel); void drm_panel_enable(struct drm_panel *panel); void drm_panel_disable(struct drm_panel *panel); int drm_panel_get_modes(struct drm_panel *panel, struct drm_connector *connector); #if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL) struct drm_panel *of_drm_find_panel(const struct device_node *np); int of_drm_get_panel_orientation(const struct device_node *np, enum drm_panel_orientation *orientation); #else static inline struct drm_panel *of_drm_find_panel(const struct device_node *np) { return ERR_PTR(-ENODEV); } static inline int of_drm_get_panel_orientation(const struct device_node *np, enum drm_panel_orientation *orientation) { return -ENODEV; } #endif #if defined(CONFIG_DRM_PANEL) bool drm_is_panel_follower(struct device *dev); int drm_panel_add_follower(struct device *follower_dev, struct drm_panel_follower *follower); void drm_panel_remove_follower(struct drm_panel_follower *follower); int devm_drm_panel_add_follower(struct device *follower_dev, struct drm_panel_follower *follower); #else static inline bool drm_is_panel_follower(struct device *dev) { return false; } static inline int drm_panel_add_follower(struct device *follower_dev, struct drm_panel_follower *follower) { return -ENODEV; } static inline void drm_panel_remove_follower(struct drm_panel_follower *follower) { } static inline int devm_drm_panel_add_follower(struct device *follower_dev, struct drm_panel_follower *follower) { return -ENODEV; } #endif #if IS_ENABLED(CONFIG_DRM_PANEL) && (IS_BUILTIN(CONFIG_BACKLIGHT_CLASS_DEVICE) || \ (IS_MODULE(CONFIG_DRM) && IS_MODULE(CONFIG_BACKLIGHT_CLASS_DEVICE))) int drm_panel_of_backlight(struct drm_panel *panel); #else static inline int drm_panel_of_backlight(struct drm_panel *panel) { return 0; } #endif #endif
