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| -rw-r--r-- | include/drm/drm_bridge.h | 980 |
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diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h new file mode 100644 index 000000000..a76f4103d --- /dev/null +++ b/include/drm/drm_bridge.h @@ -0,0 +1,980 @@ +/* + * 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/ctype.h> +#include <linux/list.h> +#include <linux/mutex.h> + +#include <drm/drm_atomic.h> +#include <drm/drm_encoder.h> +#include <drm/drm_mode_object.h> +#include <drm/drm_modes.h> + +struct drm_bridge; +struct drm_bridge_timings; +struct drm_connector; +struct drm_display_info; +struct drm_panel; +struct edid; +struct i2c_adapter; + +/** + * enum drm_bridge_attach_flags - Flags for &drm_bridge_funcs.attach + */ +enum drm_bridge_attach_flags { + /** + * @DRM_BRIDGE_ATTACH_NO_CONNECTOR: When this flag is set the bridge + * shall not create a drm_connector. + */ + DRM_BRIDGE_ATTACH_NO_CONNECTOR = BIT(0), +}; + +/** + * 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 flags argument tunes the behaviour of the attach + * operation (see DRM_BRIDGE_ATTACH_*). + * + * The @attach callback is optional. + * + * RETURNS: + * + * Zero on success, error code on failure. + */ + int (*attach)(struct drm_bridge *bridge, + enum drm_bridge_attach_flags flags); + + /** + * @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_valid: + * + * This callback is used to check if a specific mode is valid in this + * bridge. This should be implemented if the bridge has some sort of + * restriction in the modes it can display. For example, a given bridge + * may be responsible to set a clock value. If the clock can not + * produce all the values for the available modes then this callback + * can be used to restrict the number of modes to only the ones that + * can be displayed. + * + * This hook is used by the probe helpers to filter the mode list in + * drm_helper_probe_single_connector_modes(), and it is used by the + * atomic helpers to validate modes supplied by userspace in + * drm_atomic_helper_check_modeset(). + * + * The @mode_valid callback is optional. + * + * NOTE: + * + * Since this function is both called from the check phase of an atomic + * commit, and the mode validation in the probe paths it is not allowed + * to look at anything else but the passed-in mode, and validate it + * against configuration-invariant hardward constraints. Any further + * limits which depend upon the configuration can only be checked in + * @mode_fixup. + * + * RETURNS: + * + * drm_mode_status Enum + */ + enum drm_mode_status (*mode_valid)(struct drm_bridge *bridge, + const struct drm_display_info *info, + const struct drm_display_mode *mode); + + /** + * @mode_fixup: + * + * This callback is used to validate and adjust a mode. The parameter + * 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. See also &drm_crtc_state.adjusted_mode for more details. + * + * 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. &drm_bridge_funcs.mode_fixup() + * is not called when &drm_bridge_funcs.atomic_check() is implemented, + * so only one of them should be provided. + * + * 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. + * + * Also beware that userspace can request its own custom modes, neither + * core nor helpers filter modes to the list of probe modes reported by + * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure + * that modes are filtered consistently put any bridge constraints and + * limits checks into @mode_valid. + * + * 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 vfunc. If the preceding element is a &drm_encoder + * it's called right before the &drm_encoder_helper_funcs.disable, + * &drm_encoder_helper_funcs.prepare or &drm_encoder_helper_funcs.dpms + * hook. + * + * 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. + * + * NOTE: + * + * This is deprecated, do not use! + * New drivers shall use &drm_bridge_funcs.atomic_disable. + */ + 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 + * &drm_encoder_helper_funcs.disable, &drm_encoder_helper_funcs.prepare + * or &drm_encoder_helper_funcs.dpms hook. + * + * The bridge must assume that the display pipe (i.e. clocks and timing + * signals) feeding it is no longer running when this callback is + * called. + * + * The @post_disable callback is optional. + * + * NOTE: + * + * This is deprecated, do not use! + * New drivers shall use &drm_bridge_funcs.atomic_post_disable. + */ + 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. If the bridge is the first element + * then this would be &drm_encoder_helper_funcs.mode_set. The display + * pipe (i.e. clocks and timing signals) is off when this function is + * called. + * + * The adjusted_mode parameter is the mode output by the CRTC for the + * first bridge in the chain. It can be different from the mode + * parameter that contains the desired mode for the connector at the end + * of the bridges chain, for instance when the first bridge in the chain + * performs scaling. The adjusted mode is mostly useful for the first + * bridge in the chain and is likely irrelevant for the other bridges. + * + * For atomic drivers the adjusted_mode is the mode stored in + * &drm_crtc_state.adjusted_mode. + * + * NOTE: + * + * This is deprecated, do not use! + * New drivers shall set their mode in the + * &drm_bridge_funcs.atomic_enable operation. + */ + void (*mode_set)(struct drm_bridge *bridge, + const struct drm_display_mode *mode, + const 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 + * &drm_encoder_helper_funcs.enable, &drm_encoder_helper_funcs.commit or + * &drm_encoder_helper_funcs.dpms hook. + * + * 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. + * + * NOTE: + * + * This is deprecated, do not use! + * New drivers shall use &drm_bridge_funcs.atomic_pre_enable. + */ + 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 + * &drm_encoder_helper_funcs.enable, &drm_encoder_helper_funcs.commit or + * &drm_encoder_helper_funcs.dpms hook. + * + * 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. + * + * NOTE: + * + * This is deprecated, do not use! + * New drivers shall use &drm_bridge_funcs.atomic_enable. + */ + void (*enable)(struct drm_bridge *bridge); + + /** + * @atomic_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 @atomic_pre_enable or @pre_enable function. If the preceding + * element is a &drm_encoder it's called right before the encoder's + * &drm_encoder_helper_funcs.atomic_enable hook. + * + * 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. + * + * Note that this function will only be invoked in the context of an + * atomic commit. It will not be invoked from + * &drm_bridge_chain_pre_enable. It would be prudent to also provide an + * implementation of @pre_enable if you are expecting driver calls into + * &drm_bridge_chain_pre_enable. + * + * The @atomic_pre_enable callback is optional. + */ + void (*atomic_pre_enable)(struct drm_bridge *bridge, + struct drm_bridge_state *old_bridge_state); + + /** + * @atomic_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 @atomic_enable or @enable function. If the preceding element + * is a &drm_encoder it's called right after the encoder's + * &drm_encoder_helper_funcs.atomic_enable hook. + * + * 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. + * + * Note that this function will only be invoked in the context of an + * atomic commit. It will not be invoked from &drm_bridge_chain_enable. + * It would be prudent to also provide an implementation of @enable if + * you are expecting driver calls into &drm_bridge_chain_enable. + * + * The @atomic_enable callback is optional. + */ + void (*atomic_enable)(struct drm_bridge *bridge, + struct drm_bridge_state *old_bridge_state); + /** + * @atomic_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 @atomic_disable or @disable vfunc. If the preceding element + * is a &drm_encoder it's called right before the + * &drm_encoder_helper_funcs.atomic_disable hook. + * + * The bridge can assume that the display pipe (i.e. clocks and timing + * signals) feeding it is still running when this callback is called. + * + * Note that this function will only be invoked in the context of an + * atomic commit. It will not be invoked from + * &drm_bridge_chain_disable. It would be prudent to also provide an + * implementation of @disable if you are expecting driver calls into + * &drm_bridge_chain_disable. + * + * The @atomic_disable callback is optional. + */ + void (*atomic_disable)(struct drm_bridge *bridge, + struct drm_bridge_state *old_bridge_state); + + /** + * @atomic_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 + * @atomic_post_disable or @post_disable function. If the preceding + * element is a &drm_encoder it's called right after the encoder's + * &drm_encoder_helper_funcs.atomic_disable hook. + * + * The bridge must assume that the display pipe (i.e. clocks and timing + * signals) feeding it is no longer running when this callback is + * called. + * + * Note that this function will only be invoked in the context of an + * atomic commit. It will not be invoked from + * &drm_bridge_chain_post_disable. + * It would be prudent to also provide an implementation of + * @post_disable if you are expecting driver calls into + * &drm_bridge_chain_post_disable. + * + * The @atomic_post_disable callback is optional. + */ + void (*atomic_post_disable)(struct drm_bridge *bridge, + struct drm_bridge_state *old_bridge_state); + + /** + * @atomic_duplicate_state: + * + * Duplicate the current bridge state object (which is guaranteed to be + * non-NULL). + * + * The atomic_duplicate_state hook is mandatory if the bridge + * implements any of the atomic hooks, and should be left unassigned + * otherwise. For bridges that don't subclass &drm_bridge_state, the + * drm_atomic_helper_bridge_duplicate_state() helper function shall be + * used to implement this hook. + * + * RETURNS: + * A valid drm_bridge_state object or NULL if the allocation fails. + */ + struct drm_bridge_state *(*atomic_duplicate_state)(struct drm_bridge *bridge); + + /** + * @atomic_destroy_state: + * + * Destroy a bridge state object previously allocated by + * &drm_bridge_funcs.atomic_duplicate_state(). + * + * The atomic_destroy_state hook is mandatory if the bridge implements + * any of the atomic hooks, and should be left unassigned otherwise. + * For bridges that don't subclass &drm_bridge_state, the + * drm_atomic_helper_bridge_destroy_state() helper function shall be + * used to implement this hook. + */ + void (*atomic_destroy_state)(struct drm_bridge *bridge, + struct drm_bridge_state *state); + + /** + * @atomic_get_output_bus_fmts: + * + * Return the supported bus formats on the output end of a bridge. + * The returned array must be allocated with kmalloc() and will be + * freed by the caller. If the allocation fails, NULL should be + * returned. num_output_fmts must be set to the returned array size. + * Formats listed in the returned array should be listed in decreasing + * preference order (the core will try all formats until it finds one + * that works). + * + * This method is only called on the last element of the bridge chain + * as part of the bus format negotiation process that happens in + * &drm_atomic_bridge_chain_select_bus_fmts(). + * This method is optional. When not implemented, the core will + * fall back to &drm_connector.display_info.bus_formats[0] if + * &drm_connector.display_info.num_bus_formats > 0, + * or to MEDIA_BUS_FMT_FIXED otherwise. + */ + u32 *(*atomic_get_output_bus_fmts)(struct drm_bridge *bridge, + struct drm_bridge_state *bridge_state, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state, + unsigned int *num_output_fmts); + + /** + * @atomic_get_input_bus_fmts: + * + * Return the supported bus formats on the input end of a bridge for + * a specific output bus format. + * + * The returned array must be allocated with kmalloc() and will be + * freed by the caller. If the allocation fails, NULL should be + * returned. num_input_fmts must be set to the returned array size. + * Formats listed in the returned array should be listed in decreasing + * preference order (the core will try all formats until it finds one + * that works). When the format is not supported NULL should be + * returned and num_input_fmts should be set to 0. + * + * This method is called on all elements of the bridge chain as part of + * the bus format negotiation process that happens in + * drm_atomic_bridge_chain_select_bus_fmts(). + * This method is optional. When not implemented, the core will bypass + * bus format negotiation on this element of the bridge without + * failing, and the previous element in the chain will be passed + * MEDIA_BUS_FMT_FIXED as its output bus format. + * + * Bridge drivers that need to support being linked to bridges that are + * not supporting bus format negotiation should handle the + * output_fmt == MEDIA_BUS_FMT_FIXED case appropriately, by selecting a + * sensible default value or extracting this information from somewhere + * else (FW property, &drm_display_mode, &drm_display_info, ...) + * + * Note: Even if input format selection on the first bridge has no + * impact on the negotiation process (bus format negotiation stops once + * we reach the first element of the chain), drivers are expected to + * return accurate input formats as the input format may be used to + * configure the CRTC output appropriately. + */ + u32 *(*atomic_get_input_bus_fmts)(struct drm_bridge *bridge, + struct drm_bridge_state *bridge_state, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state, + u32 output_fmt, + unsigned int *num_input_fmts); + + /** + * @atomic_check: + * + * This method is responsible for checking bridge state correctness. + * It can also check the state of the surrounding components in chain + * to make sure the whole pipeline can work properly. + * + * &drm_bridge_funcs.atomic_check() hooks are called in reverse + * order (from the last to the first bridge). + * + * This method is optional. &drm_bridge_funcs.mode_fixup() is not + * called when &drm_bridge_funcs.atomic_check() is implemented, so only + * one of them should be provided. + * + * If drivers need to tweak &drm_bridge_state.input_bus_cfg.flags or + * &drm_bridge_state.output_bus_cfg.flags it should happen in + * this function. By default the &drm_bridge_state.output_bus_cfg.flags + * field is set to the next bridge + * &drm_bridge_state.input_bus_cfg.flags value or + * &drm_connector.display_info.bus_flags if the bridge is the last + * element in the chain. + * + * RETURNS: + * zero if the check passed, a negative error code otherwise. + */ + int (*atomic_check)(struct drm_bridge *bridge, + struct drm_bridge_state *bridge_state, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state); + + /** + * @atomic_reset: + * + * Reset the bridge to a predefined state (or retrieve its current + * state) and return a &drm_bridge_state object matching this state. + * This function is called at attach time. + * + * The atomic_reset hook is mandatory if the bridge implements any of + * the atomic hooks, and should be left unassigned otherwise. For + * bridges that don't subclass &drm_bridge_state, the + * drm_atomic_helper_bridge_reset() helper function shall be used to + * implement this hook. + * + * Note that the atomic_reset() semantics is not exactly matching the + * reset() semantics found on other components (connector, plane, ...). + * + * 1. The reset operation happens when the bridge is attached, not when + * drm_mode_config_reset() is called + * 2. It's meant to be used exclusively on bridges that have been + * converted to the ATOMIC API + * + * RETURNS: + * A valid drm_bridge_state object in case of success, an ERR_PTR() + * giving the reason of the failure otherwise. + */ + struct drm_bridge_state *(*atomic_reset)(struct drm_bridge *bridge); + + /** + * @detect: + * + * Check if anything is attached to the bridge output. + * + * This callback is optional, if not implemented the bridge will be + * considered as always having a component attached to its output. + * Bridges that implement this callback shall set the + * DRM_BRIDGE_OP_DETECT flag in their &drm_bridge->ops. + * + * RETURNS: + * + * drm_connector_status indicating the bridge output status. + */ + enum drm_connector_status (*detect)(struct drm_bridge *bridge); + + /** + * @get_modes: + * + * Fill all modes currently valid for the sink into the &drm_connector + * with drm_mode_probed_add(). + * + * The @get_modes callback is mostly intended to support non-probeable + * displays such as many fixed panels. Bridges that support reading + * EDID shall leave @get_modes unimplemented and implement the + * &drm_bridge_funcs->get_edid callback instead. + * + * This callback is optional. Bridges that implement it shall set the + * DRM_BRIDGE_OP_MODES flag in their &drm_bridge->ops. + * + * The connector parameter shall be used for the sole purpose of + * filling modes, and shall not be stored internally by bridge drivers + * for future usage. + * + * RETURNS: + * + * The number of modes added by calling drm_mode_probed_add(). + */ + int (*get_modes)(struct drm_bridge *bridge, + struct drm_connector *connector); + + /** + * @get_edid: + * + * Read and parse the EDID data of the connected display. + * + * The @get_edid callback is the preferred way of reporting mode + * information for a display connected to the bridge output. Bridges + * that support reading EDID shall implement this callback and leave + * the @get_modes callback unimplemented. + * + * The caller of this operation shall first verify the output + * connection status and refrain from reading EDID from a disconnected + * output. + * + * This callback is optional. Bridges that implement it shall set the + * DRM_BRIDGE_OP_EDID flag in their &drm_bridge->ops. + * + * The connector parameter shall be used for the sole purpose of EDID + * retrieval and parsing, and shall not be stored internally by bridge + * drivers for future usage. + * + * RETURNS: + * + * An edid structure newly allocated with kmalloc() (or similar) on + * success, or NULL otherwise. The caller is responsible for freeing + * the returned edid structure with kfree(). + */ + struct edid *(*get_edid)(struct drm_bridge *bridge, + struct drm_connector *connector); + + /** + * @hpd_notify: + * + * Notify the bridge of hot plug detection. + * + * This callback is optional, it may be implemented by bridges that + * need to be notified of display connection or disconnection for + * internal reasons. One use case is to reset the internal state of CEC + * controllers for HDMI bridges. + */ + void (*hpd_notify)(struct drm_bridge *bridge, + enum drm_connector_status status); + + /** + * @hpd_enable: + * + * Enable hot plug detection. From now on the bridge shall call + * drm_bridge_hpd_notify() each time a change is detected in the output + * connection status, until hot plug detection gets disabled with + * @hpd_disable. + * + * This callback is optional and shall only be implemented by bridges + * that support hot-plug notification without polling. Bridges that + * implement it shall also implement the @hpd_disable callback and set + * the DRM_BRIDGE_OP_HPD flag in their &drm_bridge->ops. + */ + void (*hpd_enable)(struct drm_bridge *bridge); + + /** + * @hpd_disable: + * + * Disable hot plug detection. Once this function returns the bridge + * shall not call drm_bridge_hpd_notify() when a change in the output + * connection status occurs. + * + * This callback is optional and shall only be implemented by bridges + * that support hot-plug notification without polling. Bridges that + * implement it shall also implement the @hpd_enable callback and set + * the DRM_BRIDGE_OP_HPD flag in their &drm_bridge->ops. + */ + void (*hpd_disable)(struct drm_bridge *bridge); + + /** + * @debugfs_init: + * + * Allows bridges to create bridge-specific debugfs files. + */ + void (*debugfs_init)(struct drm_bridge *bridge, struct dentry *root); +}; + +/** + * struct drm_bridge_timings - timing information for the bridge + */ +struct drm_bridge_timings { + /** + * @input_bus_flags: + * + * Tells what additional settings for the pixel data on the bus + * this bridge requires (like pixel signal polarity). See also + * &drm_display_info->bus_flags. + */ + u32 input_bus_flags; + /** + * @setup_time_ps: + * + * Defines the time in picoseconds the input data lines must be + * stable before the clock edge. + */ + u32 setup_time_ps; + /** + * @hold_time_ps: + * + * Defines the time in picoseconds taken for the bridge to sample the + * input signal after the clock edge. + */ + u32 hold_time_ps; + /** + * @dual_link: + * + * True if the bus operates in dual-link mode. The exact meaning is + * dependent on the bus type. For LVDS buses, this indicates that even- + * and odd-numbered pixels are received on separate links. + */ + bool dual_link; +}; + +/** + * enum drm_bridge_ops - Bitmask of operations supported by the bridge + */ +enum drm_bridge_ops { + /** + * @DRM_BRIDGE_OP_DETECT: The bridge can detect displays connected to + * its output. Bridges that set this flag shall implement the + * &drm_bridge_funcs->detect callback. + */ + DRM_BRIDGE_OP_DETECT = BIT(0), + /** + * @DRM_BRIDGE_OP_EDID: The bridge can retrieve the EDID of the display + * connected to its output. Bridges that set this flag shall implement + * the &drm_bridge_funcs->get_edid callback. + */ + DRM_BRIDGE_OP_EDID = BIT(1), + /** + * @DRM_BRIDGE_OP_HPD: The bridge can detect hot-plug and hot-unplug + * without requiring polling. Bridges that set this flag shall + * implement the &drm_bridge_funcs->hpd_enable and + * &drm_bridge_funcs->hpd_disable callbacks if they support enabling + * and disabling hot-plug detection dynamically. + */ + DRM_BRIDGE_OP_HPD = BIT(2), + /** + * @DRM_BRIDGE_OP_MODES: The bridge can retrieve the modes supported + * by the display at its output. This does not include reading EDID + * which is separately covered by @DRM_BRIDGE_OP_EDID. Bridges that set + * this flag shall implement the &drm_bridge_funcs->get_modes callback. + */ + DRM_BRIDGE_OP_MODES = BIT(3), +}; + +/** + * struct drm_bridge - central DRM bridge control structure + */ +struct drm_bridge { + /** @base: inherit from &drm_private_object */ + struct drm_private_obj base; + /** @dev: DRM device this bridge belongs to */ + struct drm_device *dev; + /** @encoder: encoder to which this bridge is connected */ + struct drm_encoder *encoder; + /** @chain_node: used to form a bridge chain */ + struct list_head chain_node; +#ifdef CONFIG_OF + /** @of_node: device node pointer to the bridge */ + struct device_node *of_node; +#endif + /** @list: to keep track of all added bridges */ + struct list_head list; + /** + * @timings: + * + * the timing specification for the bridge, if any (may be NULL) + */ + const struct drm_bridge_timings *timings; + /** @funcs: control functions */ + const struct drm_bridge_funcs *funcs; + /** @driver_private: pointer to the bridge driver's internal context */ + void *driver_private; + /** @ops: bitmask of operations supported by the bridge */ + enum drm_bridge_ops ops; + /** + * @type: Type of the connection at the bridge output + * (DRM_MODE_CONNECTOR_*). For bridges at the end of this chain this + * identifies the type of connected display. + */ + int type; + /** + * @interlace_allowed: Indicate that the bridge can handle interlaced + * modes. + */ + bool interlace_allowed; + /** + * @pre_enable_prev_first: The bridge requires that the prev + * bridge @pre_enable function is called before its @pre_enable, + * and conversely for post_disable. This is most frequently a + * requirement for DSI devices which need the host to be initialised + * before the peripheral. + */ + bool pre_enable_prev_first; + /** + * @ddc: Associated I2C adapter for DDC access, if any. + */ + struct i2c_adapter *ddc; + /** private: */ + /** + * @hpd_mutex: Protects the @hpd_cb and @hpd_data fields. + */ + struct mutex hpd_mutex; + /** + * @hpd_cb: Hot plug detection callback, registered with + * drm_bridge_hpd_enable(). + */ + void (*hpd_cb)(void *data, enum drm_connector_status status); + /** + * @hpd_data: Private data passed to the Hot plug detection callback + * @hpd_cb. + */ + void *hpd_data; +}; + +static inline struct drm_bridge * +drm_priv_to_bridge(struct drm_private_obj *priv) +{ + return container_of(priv, struct drm_bridge, base); +} + +void drm_bridge_add(struct drm_bridge *bridge); +int devm_drm_bridge_add(struct device *dev, struct drm_bridge *bridge); +void drm_bridge_remove(struct drm_bridge *bridge); +int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge, + struct drm_bridge *previous, + enum drm_bridge_attach_flags flags); + +#ifdef CONFIG_OF +struct drm_bridge *of_drm_find_bridge(struct device_node *np); +#else +static inline struct drm_bridge *of_drm_find_bridge(struct device_node *np) +{ + return NULL; +} +#endif + +/** + * drm_bridge_get_next_bridge() - Get the next bridge in the chain + * @bridge: bridge object + * + * RETURNS: + * the next bridge in the chain after @bridge, or NULL if @bridge is the last. + */ +static inline struct drm_bridge * +drm_bridge_get_next_bridge(struct drm_bridge *bridge) +{ + if (list_is_last(&bridge->chain_node, &bridge->encoder->bridge_chain)) + return NULL; + + return list_next_entry(bridge, chain_node); +} + +/** + * drm_bridge_get_prev_bridge() - Get the previous bridge in the chain + * @bridge: bridge object + * + * RETURNS: + * the previous bridge in the chain, or NULL if @bridge is the first. + */ +static inline struct drm_bridge * +drm_bridge_get_prev_bridge(struct drm_bridge *bridge) +{ + if (list_is_first(&bridge->chain_node, &bridge->encoder->bridge_chain)) + return NULL; + + return list_prev_entry(bridge, chain_node); +} + +/** + * drm_bridge_chain_get_first_bridge() - Get the first bridge in the chain + * @encoder: encoder object + * + * RETURNS: + * the first bridge in the chain, or NULL if @encoder has no bridge attached + * to it. + */ +static inline struct drm_bridge * +drm_bridge_chain_get_first_bridge(struct drm_encoder *encoder) +{ + return list_first_entry_or_null(&encoder->bridge_chain, + struct drm_bridge, chain_node); +} + +/** + * drm_for_each_bridge_in_chain() - Iterate over all bridges present in a chain + * @encoder: the encoder to iterate bridges on + * @bridge: a bridge pointer updated to point to the current bridge at each + * iteration + * + * Iterate over all bridges present in the bridge chain attached to @encoder. + */ +#define drm_for_each_bridge_in_chain(encoder, bridge) \ + list_for_each_entry(bridge, &(encoder)->bridge_chain, chain_node) + +bool drm_bridge_chain_mode_fixup(struct drm_bridge *bridge, + const struct drm_display_mode *mode, + struct drm_display_mode *adjusted_mode); +enum drm_mode_status +drm_bridge_chain_mode_valid(struct drm_bridge *bridge, + const struct drm_display_info *info, + const struct drm_display_mode *mode); +void drm_bridge_chain_disable(struct drm_bridge *bridge); +void drm_bridge_chain_post_disable(struct drm_bridge *bridge); +void drm_bridge_chain_mode_set(struct drm_bridge *bridge, + const struct drm_display_mode *mode, + const struct drm_display_mode *adjusted_mode); +void drm_bridge_chain_pre_enable(struct drm_bridge *bridge); +void drm_bridge_chain_enable(struct drm_bridge *bridge); + +int drm_atomic_bridge_chain_check(struct drm_bridge *bridge, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state); +void drm_atomic_bridge_chain_disable(struct drm_bridge *bridge, + struct drm_atomic_state *state); +void drm_atomic_bridge_chain_post_disable(struct drm_bridge *bridge, + struct drm_atomic_state *state); +void drm_atomic_bridge_chain_pre_enable(struct drm_bridge *bridge, + struct drm_atomic_state *state); +void drm_atomic_bridge_chain_enable(struct drm_bridge *bridge, + struct drm_atomic_state *state); + +u32 * +drm_atomic_helper_bridge_propagate_bus_fmt(struct drm_bridge *bridge, + struct drm_bridge_state *bridge_state, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state, + u32 output_fmt, + unsigned int *num_input_fmts); + +enum drm_connector_status drm_bridge_detect(struct drm_bridge *bridge); +int drm_bridge_get_modes(struct drm_bridge *bridge, + struct drm_connector *connector); +struct edid *drm_bridge_get_edid(struct drm_bridge *bridge, + struct drm_connector *connector); +void drm_bridge_hpd_enable(struct drm_bridge *bridge, + void (*cb)(void *data, + enum drm_connector_status status), + void *data); +void drm_bridge_hpd_disable(struct drm_bridge *bridge); +void drm_bridge_hpd_notify(struct drm_bridge *bridge, + enum drm_connector_status status); + +#ifdef CONFIG_DRM_PANEL_BRIDGE +bool drm_bridge_is_panel(const struct drm_bridge *bridge); +struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel); +struct drm_bridge *drm_panel_bridge_add_typed(struct drm_panel *panel, + u32 connector_type); +void drm_panel_bridge_remove(struct drm_bridge *bridge); +int drm_panel_bridge_set_orientation(struct drm_connector *connector, + struct drm_bridge *bridge); +struct drm_bridge *devm_drm_panel_bridge_add(struct device *dev, + struct drm_panel *panel); +struct drm_bridge *devm_drm_panel_bridge_add_typed(struct device *dev, + struct drm_panel *panel, + u32 connector_type); +struct drm_bridge *drmm_panel_bridge_add(struct drm_device *drm, + struct drm_panel *panel); +struct drm_connector *drm_panel_bridge_connector(struct drm_bridge *bridge); +#else +static inline bool drm_bridge_is_panel(const struct drm_bridge *bridge) +{ + return false; +} + +static inline int drm_panel_bridge_set_orientation(struct drm_connector *connector, + struct drm_bridge *bridge) +{ + return -EINVAL; +} +#endif + +#if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL_BRIDGE) +struct drm_bridge *devm_drm_of_get_bridge(struct device *dev, struct device_node *node, + u32 port, u32 endpoint); +struct drm_bridge *drmm_of_get_bridge(struct drm_device *drm, struct device_node *node, + u32 port, u32 endpoint); +#else +static inline struct drm_bridge *devm_drm_of_get_bridge(struct device *dev, + struct device_node *node, + u32 port, + u32 endpoint) +{ + return ERR_PTR(-ENODEV); +} + +static inline struct drm_bridge *drmm_of_get_bridge(struct drm_device *drm, + struct device_node *node, + u32 port, + u32 endpoint) +{ + return ERR_PTR(-ENODEV); +} +#endif + +#endif |