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/*
* 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 device_node;
struct drm_bridge;
struct drm_bridge_timings;
struct drm_connector;
struct drm_display_info;
struct drm_minor;
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.
*
* 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.
*
* 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.
*
* 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.
*
* 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);
/**
* @edid_read:
*
* Read the EDID data of the connected display.
*
* The @edid_read 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 shall not be stored internally by bridge drivers for
* future usage.
*
* RETURNS:
*
* An edid structure newly allocated with drm_edid_alloc() or returned
* from drm_edid_read() family of functions on success, or NULL
* otherwise. The caller is responsible for freeing the returned edid
* structure with drm_edid_free().
*/
const struct drm_edid *(*edid_read)(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;
/** @of_node: device node pointer to the bridge */
struct device_node *of_node;
/** @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_mode_set(struct drm_bridge *bridge,
const struct drm_display_mode *mode,
const struct drm_display_mode *adjusted_mode);
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);
const struct drm_edid *drm_bridge_edid_read(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
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