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Diffstat (limited to '')
| -rw-r--r-- | include/drm/drm_panel.h | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h new file mode 100644 index 000000000..675aa1e87 --- /dev/null +++ b/include/drm/drm_panel.h @@ -0,0 +1,207 @@ +/* + * 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> + +struct device_node; +struct drm_connector; +struct drm_device; +struct drm_panel; +struct display_timing; + +/** + * struct drm_panel_funcs - perform operations on a given panel + * @disable: disable panel (turn off back light, etc.) + * @unprepare: turn off panel + * @prepare: turn on panel and perform set up + * @enable: enable panel (turn on back light, etc.) + * @get_modes: add modes to the connector that the panel is attached to and + * return the number of modes added + * @get_timings: copy display timings into the provided array and return + * the number of display timings available + * + * 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. + */ +struct drm_panel_funcs { + int (*disable)(struct drm_panel *panel); + int (*unprepare)(struct drm_panel *panel); + int (*prepare)(struct drm_panel *panel); + int (*enable)(struct drm_panel *panel); + int (*get_modes)(struct drm_panel *panel); + int (*get_timings)(struct drm_panel *panel, unsigned int num_timings, + struct display_timing *timings); +}; + +/** + * struct drm_panel - DRM panel object + * @drm: DRM device owning the panel + * @connector: DRM connector that the panel is attached to + * @dev: parent device of the panel + * @funcs: operations that can be performed on the panel + * @list: panel entry in registry + */ +struct drm_panel { + struct drm_device *drm; + struct drm_connector *connector; + struct device *dev; + + const struct drm_panel_funcs *funcs; + + struct list_head list; +}; + +/** + * drm_disable_unprepare - power off a panel + * @panel: DRM panel + * + * Calling this function will completely power off a panel (assert the panel's + * reset, turn off power supplies, ...). After this function has completed, it + * is usually no longer possible to communicate with the panel until another + * call to drm_panel_prepare(). + * + * Return: 0 on success or a negative error code on failure. + */ +static inline int drm_panel_unprepare(struct drm_panel *panel) +{ + if (panel && panel->funcs && panel->funcs->unprepare) + return panel->funcs->unprepare(panel); + + return panel ? -ENOSYS : -EINVAL; +} + +/** + * drm_panel_disable - disable a panel + * @panel: DRM panel + * + * This will typically turn off the panel's backlight or disable the display + * drivers. For smart panels it should still be possible to communicate with + * the integrated circuitry via any command bus after this call. + * + * Return: 0 on success or a negative error code on failure. + */ +static inline int drm_panel_disable(struct drm_panel *panel) +{ + if (panel && panel->funcs && panel->funcs->disable) + return panel->funcs->disable(panel); + + return panel ? -ENOSYS : -EINVAL; +} + +/** + * drm_panel_prepare - power on a panel + * @panel: DRM panel + * + * Calling this function will enable power and deassert any reset signals to + * the panel. After this has completed it is possible to communicate with any + * integrated circuitry via a command bus. + * + * Return: 0 on success or a negative error code on failure. + */ +static inline int drm_panel_prepare(struct drm_panel *panel) +{ + if (panel && panel->funcs && panel->funcs->prepare) + return panel->funcs->prepare(panel); + + return panel ? -ENOSYS : -EINVAL; +} + +/** + * drm_panel_enable - enable a panel + * @panel: DRM panel + * + * Calling this function will cause the panel display drivers to be turned on + * and the backlight to be enabled. Content will be visible on screen after + * this call completes. + * + * Return: 0 on success or a negative error code on failure. + */ +static inline int drm_panel_enable(struct drm_panel *panel) +{ + if (panel && panel->funcs && panel->funcs->enable) + return panel->funcs->enable(panel); + + return panel ? -ENOSYS : -EINVAL; +} + +/** + * drm_panel_get_modes - probe the available display modes of a panel + * @panel: DRM panel + * + * The modes probed from the panel are automatically added to the connector + * that the panel is attached to. + * + * Return: The number of modes available from the panel on success or a + * negative error code on failure. + */ +static inline int drm_panel_get_modes(struct drm_panel *panel) +{ + if (panel && panel->funcs && panel->funcs->get_modes) + return panel->funcs->get_modes(panel); + + return panel ? -ENOSYS : -EINVAL; +} + +void drm_panel_init(struct drm_panel *panel); + +int drm_panel_add(struct drm_panel *panel); +void drm_panel_remove(struct drm_panel *panel); + +int drm_panel_attach(struct drm_panel *panel, struct drm_connector *connector); +int drm_panel_detach(struct drm_panel *panel); + +#if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL) +struct drm_panel *of_drm_find_panel(const struct device_node *np); +#else +static inline struct drm_panel *of_drm_find_panel(const struct device_node *np) +{ + return ERR_PTR(-ENODEV); +} +#endif + +#endif |