/* * Copyright (c) 2016 Intel Corporation * * 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. */ #ifndef __DRM_BRIDGE_H__ #define __DRM_BRIDGE_H__ #include <linux/list.h> #include <linux/ctype.h> #include <drm/drm_mode_object.h> #include <drm/drm_modes.h> struct drm_bridge; /** * struct drm_bridge_funcs - drm_bridge control functions */ struct drm_bridge_funcs { /** * @attach: * * This callback is invoked whenever our bridge is being attached to a * &drm_encoder. * * The attach callback is optional. * * RETURNS: * * Zero on success, error code on failure. */ int (*attach)(struct drm_bridge *bridge); /** * @detach: * * This callback is invoked whenever our bridge is being detached from a * &drm_encoder. * * The detach callback is optional. */ void (*detach)(struct drm_bridge *bridge); /** * @mode_fixup: * * This callback is used to validate and adjust a mode. The paramater * mode is the display mode that should be fed to the next element in * the display chain, either the final &drm_connector or the next * &drm_bridge. The parameter adjusted_mode is the input mode the bridge * requires. It can be modified by this callback and does not need to * match mode. * * This is the only hook that allows a bridge to reject a modeset. If * this function passes all other callbacks must succeed for this * configuration. * * The mode_fixup callback is optional. * * NOTE: * * This function is called in the check phase of atomic modesets, which * can be aborted for any reason (including on userspace's request to * just check whether a configuration would be possible). Drivers MUST * NOT touch any persistent state (hardware or software) or data * structures except the passed in @state parameter. * * RETURNS: * * True if an acceptable configuration is possible, false if the modeset * operation should be rejected. */ bool (*mode_fixup)(struct drm_bridge *bridge, const struct drm_display_mode *mode, struct drm_display_mode *adjusted_mode); /** * @disable: * * This callback should disable the bridge. It is called right before * the preceding element in the display pipe is disabled. If the * preceding element is a bridge this means it's called before that * bridge's ->disable() function. If the preceding element is a * &drm_encoder it's called right before the encoder's ->disable(), * ->prepare() or ->dpms() hook from struct &drm_encoder_helper_funcs. * * The bridge can assume that the display pipe (i.e. clocks and timing * signals) feeding it is still running when this callback is called. * * The disable callback is optional. */ void (*disable)(struct drm_bridge *bridge); /** * @post_disable: * * This callback should disable the bridge. It is called right after * the preceding element in the display pipe is disabled. If the * preceding element is a bridge this means it's called after that * bridge's ->post_disable() function. If the preceding element is a * &drm_encoder it's called right after the encoder's ->disable(), * ->prepare() or ->dpms() hook from struct &drm_encoder_helper_funcs. * * The bridge must assume that the display pipe (i.e. clocks and timing * singals) feeding it is no longer running when this callback is * called. * * The post_disable callback is optional. */ void (*post_disable)(struct drm_bridge *bridge); /** * @mode_set: * * This callback should set the given mode on the bridge. It is called * after the ->mode_set() callback for the preceding element in the * display pipeline has been called already. The display pipe (i.e. * clocks and timing signals) is off when this function is called. */ void (*mode_set)(struct drm_bridge *bridge, struct drm_display_mode *mode, struct drm_display_mode *adjusted_mode); /** * @pre_enable: * * This callback should enable the bridge. It is called right before * the preceding element in the display pipe is enabled. If the * preceding element is a bridge this means it's called before that * bridge's ->pre_enable() function. If the preceding element is a * &drm_encoder it's called right before the encoder's ->enable(), * ->commit() or ->dpms() hook from struct &drm_encoder_helper_funcs. * * The display pipe (i.e. clocks and timing signals) feeding this bridge * will not yet be running when this callback is called. The bridge must * not enable the display link feeding the next bridge in the chain (if * there is one) when this callback is called. * * The pre_enable callback is optional. */ void (*pre_enable)(struct drm_bridge *bridge); /** * @enable: * * This callback should enable the bridge. It is called right after * the preceding element in the display pipe is enabled. If the * preceding element is a bridge this means it's called after that * bridge's ->enable() function. If the preceding element is a * &drm_encoder it's called right after the encoder's ->enable(), * ->commit() or ->dpms() hook from struct &drm_encoder_helper_funcs. * * The bridge can assume that the display pipe (i.e. clocks and timing * signals) feeding it is running when this callback is called. This * callback must enable the display link feeding the next bridge in the * chain if there is one. * * The enable callback is optional. */ void (*enable)(struct drm_bridge *bridge); }; /** * struct drm_bridge - central DRM bridge control structure * @dev: DRM device this bridge belongs to * @encoder: encoder to which this bridge is connected * @next: the next bridge in the encoder chain * @of_node: device node pointer to the bridge * @list: to keep track of all added bridges * @funcs: control functions * @driver_private: pointer to the bridge driver's internal context */ struct drm_bridge { struct drm_device *dev; struct drm_encoder *encoder; struct drm_bridge *next; #ifdef CONFIG_OF struct device_node *of_node; #endif struct list_head list; const struct drm_bridge_funcs *funcs; void *driver_private; }; int drm_bridge_add(struct drm_bridge *bridge); void drm_bridge_remove(struct drm_bridge *bridge); struct drm_bridge *of_drm_find_bridge(struct device_node *np); int drm_bridge_attach(struct drm_device *dev, struct drm_bridge *bridge); void drm_bridge_detach(struct drm_bridge *bridge); bool drm_bridge_mode_fixup(struct drm_bridge *bridge, const struct drm_display_mode *mode, struct drm_display_mode *adjusted_mode); void drm_bridge_disable(struct drm_bridge *bridge); void drm_bridge_post_disable(struct drm_bridge *bridge); void drm_bridge_mode_set(struct drm_bridge *bridge, struct drm_display_mode *mode, struct drm_display_mode *adjusted_mode); void drm_bridge_pre_enable(struct drm_bridge *bridge); void drm_bridge_enable(struct drm_bridge *bridge); #endif