2 * Copyright (c) 2016 Intel Corporation
4 * Permission to use, copy, modify, distribute, and sell this software and its
5 * documentation for any purpose is hereby granted without fee, provided that
6 * the above copyright notice appear in all copies and that both that copyright
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14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
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23 #ifndef __DRM_CONNECTOR_H__
24 #define __DRM_CONNECTOR_H__
26 #include <linux/list.h>
27 #include <linux/ctype.h>
28 #include <drm/drm_mode_object.h>
30 #include <uapi/drm/drm_mode.h>
34 struct drm_connector_helper_funcs
;
39 struct drm_property_blob
;
42 enum drm_connector_force
{
43 DRM_FORCE_UNSPECIFIED
,
45 DRM_FORCE_ON
, /* force on analog part normally */
46 DRM_FORCE_ON_DIGITAL
, /* for DVI-I use digital connector */
50 * enum drm_connector_status - status for a &drm_connector
52 * This enum is used to track the connector status. There are no separate
53 * #defines for the uapi!
55 enum drm_connector_status
{
57 * @connector_status_connected: The connector is definitely connected to
58 * a sink device, and can be enabled.
60 connector_status_connected
= 1,
62 * @connector_status_disconnected: The connector isn't connected to a
63 * sink device which can be autodetect. For digital outputs like DP or
64 * HDMI (which can be realiable probed) this means there's really
65 * nothing there. It is driver-dependent whether a connector with this
66 * status can be lit up or not.
68 connector_status_disconnected
= 2,
70 * @connector_status_unknown: The connector's status could not be
71 * reliably detected. This happens when probing would either cause
72 * flicker (like load-detection when the connector is in use), or when a
73 * hardware resource isn't available (like when load-detection needs a
74 * free CRTC). It should be possible to light up the connector with one
75 * of the listed fallback modes. For default configuration userspace
76 * should only try to light up connectors with unknown status when
77 * there's not connector with @connector_status_connected.
79 connector_status_unknown
= 3,
84 SubPixelHorizontalRGB
,
85 SubPixelHorizontalBGR
,
92 * struct drm_display_info - runtime data about the connected sink
94 * Describes a given display (e.g. CRT or flat panel) and its limitations. For
95 * fixed display sinks like built-in panels there's not much difference between
96 * this and struct &drm_connector. But for sinks with a real cable this
97 * structure is meant to describe all the things at the other end of the cable.
99 * For sinks which provide an EDID this can be filled out by calling
100 * drm_add_edid_modes().
102 struct drm_display_info
{
104 * @name: Name of the display.
106 char name
[DRM_DISPLAY_INFO_LEN
];
109 * @width_mm: Physical width in mm.
111 unsigned int width_mm
;
113 * @height_mm: Physical height in mm.
115 unsigned int height_mm
;
118 * @pixel_clock: Maximum pixel clock supported by the sink, in units of
119 * 100Hz. This mismatches the clok in &drm_display_mode (which is in
120 * kHZ), because that's what the EDID uses as base unit.
122 unsigned int pixel_clock
;
124 * @bpc: Maximum bits per color channel. Used by HDMI and DP outputs.
129 * @subpixel_order: Subpixel order of LCD panels.
131 enum subpixel_order subpixel_order
;
133 #define DRM_COLOR_FORMAT_RGB444 (1<<0)
134 #define DRM_COLOR_FORMAT_YCRCB444 (1<<1)
135 #define DRM_COLOR_FORMAT_YCRCB422 (1<<2)
138 * @color_formats: HDMI Color formats, selects between RGB and YCrCb
139 * modes. Used DRM_COLOR_FORMAT\_ defines, which are _not_ the same ones
140 * as used to describe the pixel format in framebuffers, and also don't
141 * match the formats in @bus_formats which are shared with v4l.
146 * @bus_formats: Pixel data format on the wire, somewhat redundant with
147 * @color_formats. Array of size @num_bus_formats encoded using
148 * MEDIA_BUS_FMT\_ defines shared with v4l and media drivers.
150 const u32
*bus_formats
;
152 * @num_bus_formats: Size of @bus_formats array.
154 unsigned int num_bus_formats
;
156 #define DRM_BUS_FLAG_DE_LOW (1<<0)
157 #define DRM_BUS_FLAG_DE_HIGH (1<<1)
158 /* drive data on pos. edge */
159 #define DRM_BUS_FLAG_PIXDATA_POSEDGE (1<<2)
160 /* drive data on neg. edge */
161 #define DRM_BUS_FLAG_PIXDATA_NEGEDGE (1<<3)
164 * @bus_flags: Additional information (like pixel signal polarity) for
165 * the pixel data on the bus, using DRM_BUS_FLAGS\_ defines.
170 * @max_tmds_clock: Maximum TMDS clock rate supported by the
171 * sink in kHz. 0 means undefined.
176 * @dvi_dual: Dual-link DVI sink?
181 * @edid_hdmi_dc_modes: Mask of supported hdmi deep color modes. Even
182 * more stuff redundant with @bus_formats.
184 u8 edid_hdmi_dc_modes
;
187 * @cea_rev: CEA revision of the HDMI sink.
192 int drm_display_info_set_bus_formats(struct drm_display_info
*info
,
194 unsigned int num_formats
);
197 * struct drm_connector_state - mutable connector state
198 * @connector: backpointer to the connector
199 * @best_encoder: can be used by helpers and drivers to select the encoder
200 * @state: backpointer to global drm_atomic_state
202 struct drm_connector_state
{
203 struct drm_connector
*connector
;
206 * @crtc: CRTC to connect connector to, NULL if disabled.
208 * Do not change this directly, use drm_atomic_set_crtc_for_connector()
211 struct drm_crtc
*crtc
;
213 struct drm_encoder
*best_encoder
;
215 struct drm_atomic_state
*state
;
219 * struct drm_connector_funcs - control connectors on a given device
221 * Each CRTC may have one or more connectors attached to it. The functions
222 * below allow the core DRM code to control connectors, enumerate available modes,
225 struct drm_connector_funcs
{
229 * Legacy entry point to set the per-connector DPMS state. Legacy DPMS
230 * is exposed as a standard property on the connector, but diverted to
231 * this callback in the drm core. Note that atomic drivers don't
232 * implement the 4 level DPMS support on the connector any more, but
233 * instead only have an on/off "ACTIVE" property on the CRTC object.
235 * Drivers implementing atomic modeset should use
236 * drm_atomic_helper_connector_dpms() to implement this hook.
240 * 0 on success or a negative error code on failure.
242 int (*dpms
)(struct drm_connector
*connector
, int mode
);
247 * Reset connector hardware and software state to off. This function isn't
248 * called by the core directly, only through drm_mode_config_reset().
249 * It's not a helper hook only for historical reasons.
251 * Atomic drivers can use drm_atomic_helper_connector_reset() to reset
252 * atomic state using this hook.
254 void (*reset
)(struct drm_connector
*connector
);
259 * Check to see if anything is attached to the connector. The parameter
260 * force is set to false whilst polling, true when checking the
261 * connector due to a user request. force can be used by the driver to
262 * avoid expensive, destructive operations during automated probing.
266 * Note that this hook is only called by the probe helper. It's not in
267 * the helper library vtable purely for historical reasons. The only DRM
268 * core entry point to probe connector state is @fill_modes.
272 * drm_connector_status indicating the connector's status.
274 enum drm_connector_status (*detect
)(struct drm_connector
*connector
,
280 * This function is called to update internal encoder state when the
281 * connector is forced to a certain state by userspace, either through
282 * the sysfs interfaces or on the kernel cmdline. In that case the
283 * @detect callback isn't called.
287 * Note that this hook is only called by the probe helper. It's not in
288 * the helper library vtable purely for historical reasons. The only DRM
289 * core entry point to probe connector state is @fill_modes.
291 void (*force
)(struct drm_connector
*connector
);
296 * Entry point for output detection and basic mode validation. The
297 * driver should reprobe the output if needed (e.g. when hotplug
298 * handling is unreliable), add all detected modes to connector->modes
299 * and filter out any the device can't support in any configuration. It
300 * also needs to filter out any modes wider or higher than the
301 * parameters max_width and max_height indicate.
303 * The drivers must also prune any modes no longer valid from
304 * connector->modes. Furthermore it must update connector->status and
305 * connector->edid. If no EDID has been received for this output
306 * connector->edid must be NULL.
308 * Drivers using the probe helpers should use
309 * drm_helper_probe_single_connector_modes() or
310 * drm_helper_probe_single_connector_modes_nomerge() to implement this
315 * The number of modes detected and filled into connector->modes.
317 int (*fill_modes
)(struct drm_connector
*connector
, uint32_t max_width
, uint32_t max_height
);
322 * This is the legacy entry point to update a property attached to the
325 * Drivers implementing atomic modeset should use
326 * drm_atomic_helper_connector_set_property() to implement this hook.
328 * This callback is optional if the driver does not support any legacy
329 * driver-private properties.
333 * 0 on success or a negative error code on failure.
335 int (*set_property
)(struct drm_connector
*connector
, struct drm_property
*property
,
341 * This optional hook can be used to register additional userspace
342 * interfaces attached to the connector, light backlight control, i2c,
343 * DP aux or similar interfaces. It is called late in the driver load
344 * sequence from drm_connector_register() when registering all the
345 * core drm connector interfaces. Everything added from this callback
346 * should be unregistered in the early_unregister callback.
348 * This is called while holding drm_connector->mutex.
352 * 0 on success, or a negative error code on failure.
354 int (*late_register
)(struct drm_connector
*connector
);
359 * This optional hook should be used to unregister the additional
360 * userspace interfaces attached to the connector from
361 * late_register(). It is called from drm_connector_unregister(),
362 * early in the driver unload sequence to disable userspace access
363 * before data structures are torndown.
365 * This is called while holding drm_connector->mutex.
367 void (*early_unregister
)(struct drm_connector
*connector
);
372 * Clean up connector resources. This is called at driver unload time
373 * through drm_mode_config_cleanup(). It can also be called at runtime
374 * when a connector is being hot-unplugged for drivers that support
375 * connector hotplugging (e.g. DisplayPort MST).
377 void (*destroy
)(struct drm_connector
*connector
);
380 * @atomic_duplicate_state:
382 * Duplicate the current atomic state for this connector and return it.
383 * The core and helpers guarantee that any atomic state duplicated with
384 * this hook and still owned by the caller (i.e. not transferred to the
385 * driver by calling ->atomic_commit() from struct
386 * &drm_mode_config_funcs) will be cleaned up by calling the
387 * @atomic_destroy_state hook in this structure.
389 * Atomic drivers which don't subclass struct &drm_connector_state should use
390 * drm_atomic_helper_connector_duplicate_state(). Drivers that subclass the
391 * state structure to extend it with driver-private state should use
392 * __drm_atomic_helper_connector_duplicate_state() to make sure shared state is
393 * duplicated in a consistent fashion across drivers.
395 * It is an error to call this hook before connector->state has been
396 * initialized correctly.
400 * If the duplicate state references refcounted resources this hook must
401 * acquire a reference for each of them. The driver must release these
402 * references again in @atomic_destroy_state.
406 * Duplicated atomic state or NULL when the allocation failed.
408 struct drm_connector_state
*(*atomic_duplicate_state
)(struct drm_connector
*connector
);
411 * @atomic_destroy_state:
413 * Destroy a state duplicated with @atomic_duplicate_state and release
414 * or unreference all resources it references
416 void (*atomic_destroy_state
)(struct drm_connector
*connector
,
417 struct drm_connector_state
*state
);
420 * @atomic_set_property:
422 * Decode a driver-private property value and store the decoded value
423 * into the passed-in state structure. Since the atomic core decodes all
424 * standardized properties (even for extensions beyond the core set of
425 * properties which might not be implemented by all drivers) this
426 * requires drivers to subclass the state structure.
428 * Such driver-private properties should really only be implemented for
429 * truly hardware/vendor specific state. Instead it is preferred to
430 * standardize atomic extension and decode the properties used to expose
431 * such an extension in the core.
433 * Do not call this function directly, use
434 * drm_atomic_connector_set_property() instead.
436 * This callback is optional if the driver does not support any
437 * driver-private atomic properties.
441 * This function is called in the state assembly phase of atomic
442 * modesets, which can be aborted for any reason (including on
443 * userspace's request to just check whether a configuration would be
444 * possible). Drivers MUST NOT touch any persistent state (hardware or
445 * software) or data structures except the passed in @state parameter.
447 * Also since userspace controls in which order properties are set this
448 * function must not do any input validation (since the state update is
449 * incomplete and hence likely inconsistent). Instead any such input
450 * validation must be done in the various atomic_check callbacks.
454 * 0 if the property has been found, -EINVAL if the property isn't
455 * implemented by the driver (which shouldn't ever happen, the core only
456 * asks for properties attached to this connector). No other validation
457 * is allowed by the driver. The core already checks that the property
458 * value is within the range (integer, valid enum value, ...) the driver
459 * set when registering the property.
461 int (*atomic_set_property
)(struct drm_connector
*connector
,
462 struct drm_connector_state
*state
,
463 struct drm_property
*property
,
467 * @atomic_get_property:
469 * Reads out the decoded driver-private property. This is used to
470 * implement the GETCONNECTOR IOCTL.
472 * Do not call this function directly, use
473 * drm_atomic_connector_get_property() instead.
475 * This callback is optional if the driver does not support any
476 * driver-private atomic properties.
480 * 0 on success, -EINVAL if the property isn't implemented by the
481 * driver (which shouldn't ever happen, the core only asks for
482 * properties attached to this connector).
484 int (*atomic_get_property
)(struct drm_connector
*connector
,
485 const struct drm_connector_state
*state
,
486 struct drm_property
*property
,
490 /* mode specified on the command line */
491 struct drm_cmdline_mode
{
493 bool refresh_specified
;
502 enum drm_connector_force force
;
506 * struct drm_connector - central DRM connector control structure
507 * @dev: parent DRM device
508 * @kdev: kernel device for sysfs attributes
509 * @attr: sysfs attributes
510 * @head: list management
511 * @base: base KMS object
512 * @name: human readable name, can be overwritten by the driver
513 * @connector_type: one of the DRM_MODE_CONNECTOR_<foo> types from drm_mode.h
514 * @connector_type_id: index into connector type enum
515 * @interlace_allowed: can this connector handle interlaced modes?
516 * @doublescan_allowed: can this connector handle doublescan?
517 * @stereo_allowed: can this connector handle stereo modes?
518 * @modes: modes available on this connector (from fill_modes() + user)
519 * @status: one of the drm_connector_status enums (connected, not, or unknown)
520 * @probed_modes: list of modes derived directly from the display
521 * @funcs: connector control functions
522 * @edid_blob_ptr: DRM property containing EDID if present
523 * @properties: property tracking for this connector
524 * @dpms: current dpms state
525 * @helper_private: mid-layer private data
526 * @cmdline_mode: mode line parsed from the kernel cmdline for this connector
527 * @force: a DRM_FORCE_<foo> state for forced mode sets
528 * @override_edid: has the EDID been overwritten through debugfs for testing?
529 * @encoder_ids: valid encoders for this connector
530 * @encoder: encoder driving this connector, if any
531 * @eld: EDID-like data, if present
532 * @latency_present: AV delay info from ELD, if found
533 * @video_latency: video latency info from ELD, if found
534 * @audio_latency: audio latency info from ELD, if found
535 * @null_edid_counter: track sinks that give us all zeros for the EDID
536 * @bad_edid_counter: track sinks that give us an EDID with invalid checksum
537 * @edid_corrupt: indicates whether the last read EDID was corrupt
538 * @debugfs_entry: debugfs directory for this connector
539 * @state: current atomic state for this connector
540 * @has_tile: is this connector connected to a tiled monitor
541 * @tile_group: tile group for the connected monitor
542 * @tile_is_single_monitor: whether the tile is one monitor housing
543 * @num_h_tile: number of horizontal tiles in the tile group
544 * @num_v_tile: number of vertical tiles in the tile group
545 * @tile_h_loc: horizontal location of this tile
546 * @tile_v_loc: vertical location of this tile
547 * @tile_h_size: horizontal size of this tile.
548 * @tile_v_size: vertical size of this tile.
550 * Each connector may be connected to one or more CRTCs, or may be clonable by
551 * another connector if they can share a CRTC. Each connector also has a specific
552 * position in the broader display (referred to as a 'screen' though it could
553 * span multiple monitors).
555 struct drm_connector
{
556 struct drm_device
*dev
;
558 struct device_attribute
*attr
;
559 struct list_head head
;
561 struct drm_mode_object base
;
566 * @mutex: Lock for general connector state, but currently only protects
567 * @registered. Most of the connector state is still protected by the
568 * mutex in &drm_mode_config.
573 * @index: Compacted connector index, which matches the position inside
574 * the mode_config.list for drivers not supporting hot-add/removing. Can
575 * be used as an array index. It is invariant over the lifetime of the
581 int connector_type_id
;
582 bool interlace_allowed
;
583 bool doublescan_allowed
;
586 * @registered: Is this connector exposed (registered) with userspace?
587 * Protected by @mutex.
590 struct list_head modes
; /* list of modes on this connector */
592 enum drm_connector_status status
;
594 /* these are modes added by probing with DDC or the BIOS */
595 struct list_head probed_modes
;
598 * @display_info: Display information is filled from EDID information
599 * when a display is detected. For non hot-pluggable displays such as
600 * flat panels in embedded systems, the driver should initialize the
601 * display_info.width_mm and display_info.height_mm fields with the
602 * physical size of the display.
604 struct drm_display_info display_info
;
605 const struct drm_connector_funcs
*funcs
;
607 struct drm_property_blob
*edid_blob_ptr
;
608 struct drm_object_properties properties
;
613 * DRM blob property data for the DP MST path property.
615 struct drm_property_blob
*path_blob_ptr
;
620 * DRM blob property data for the tile property (used mostly by DP MST).
621 * This is meant for screens which are driven through separate display
622 * pipelines represented by &drm_crtc, which might not be running with
623 * genlocked clocks. For tiled panels which are genlocked, like
624 * dual-link LVDS or dual-link DSI, the driver should try to not expose
625 * the tiling and virtualize both &drm_crtc and &drm_plane if needed.
627 struct drm_property_blob
*tile_blob_ptr
;
629 /* should we poll this connector for connects and disconnects */
630 /* hot plug detectable */
631 #define DRM_CONNECTOR_POLL_HPD (1 << 0)
632 /* poll for connections */
633 #define DRM_CONNECTOR_POLL_CONNECT (1 << 1)
634 /* can cleanly poll for disconnections without flickering the screen */
635 /* DACs should rarely do this without a lot of testing */
636 #define DRM_CONNECTOR_POLL_DISCONNECT (1 << 2)
641 * Connector polling mode, a combination of
643 * DRM_CONNECTOR_POLL_HPD
644 * The connector generates hotplug events and doesn't need to be
645 * periodically polled. The CONNECT and DISCONNECT flags must not
646 * be set together with the HPD flag.
648 * DRM_CONNECTOR_POLL_CONNECT
649 * Periodically poll the connector for connection.
651 * DRM_CONNECTOR_POLL_DISCONNECT
652 * Periodically poll the connector for disconnection.
654 * Set to 0 for connectors that don't support connection status
659 /* requested DPMS state */
662 const struct drm_connector_helper_funcs
*helper_private
;
664 /* forced on connector */
665 struct drm_cmdline_mode cmdline_mode
;
666 enum drm_connector_force force
;
669 #define DRM_CONNECTOR_MAX_ENCODER 3
670 uint32_t encoder_ids
[DRM_CONNECTOR_MAX_ENCODER
];
671 struct drm_encoder
*encoder
; /* currently active encoder */
673 #define MAX_ELD_BYTES 128
675 uint8_t eld
[MAX_ELD_BYTES
];
676 bool latency_present
[2];
677 int video_latency
[2]; /* [0]: progressive, [1]: interlaced */
678 int audio_latency
[2];
679 int null_edid_counter
; /* needed to workaround some HW bugs where we get all 0s */
680 unsigned bad_edid_counter
;
682 /* Flag for raw EDID header corruption - used in Displayport
683 * compliance testing - * Displayport Link CTS Core 1.2 rev1.1 4.2.2.6
687 struct dentry
*debugfs_entry
;
689 struct drm_connector_state
*state
;
693 struct drm_tile_group
*tile_group
;
694 bool tile_is_single_monitor
;
696 uint8_t num_h_tile
, num_v_tile
;
697 uint8_t tile_h_loc
, tile_v_loc
;
698 uint16_t tile_h_size
, tile_v_size
;
701 #define obj_to_connector(x) container_of(x, struct drm_connector, base)
703 int drm_connector_init(struct drm_device
*dev
,
704 struct drm_connector
*connector
,
705 const struct drm_connector_funcs
*funcs
,
707 int drm_connector_register(struct drm_connector
*connector
);
708 void drm_connector_unregister(struct drm_connector
*connector
);
709 int drm_mode_connector_attach_encoder(struct drm_connector
*connector
,
710 struct drm_encoder
*encoder
);
712 void drm_connector_cleanup(struct drm_connector
*connector
);
713 static inline unsigned drm_connector_index(struct drm_connector
*connector
)
715 return connector
->index
;
719 * drm_connector_lookup - lookup connector object
721 * @id: connector object id
723 * This function looks up the connector object specified by id
724 * add takes a reference to it.
726 static inline struct drm_connector
*drm_connector_lookup(struct drm_device
*dev
,
729 struct drm_mode_object
*mo
;
730 mo
= drm_mode_object_find(dev
, id
, DRM_MODE_OBJECT_CONNECTOR
);
731 return mo
? obj_to_connector(mo
) : NULL
;
735 * drm_connector_reference - incr the connector refcnt
736 * @connector: connector
738 * This function increments the connector's refcount.
740 static inline void drm_connector_reference(struct drm_connector
*connector
)
742 drm_mode_object_reference(&connector
->base
);
746 * drm_connector_unreference - unref a connector
747 * @connector: connector to unref
749 * This function decrements the connector's refcount and frees it if it drops to zero.
751 static inline void drm_connector_unreference(struct drm_connector
*connector
)
753 drm_mode_object_unreference(&connector
->base
);
756 const char *drm_get_connector_status_name(enum drm_connector_status status
);
757 const char *drm_get_subpixel_order_name(enum subpixel_order order
);
758 const char *drm_get_dpms_name(int val
);
759 const char *drm_get_dvi_i_subconnector_name(int val
);
760 const char *drm_get_dvi_i_select_name(int val
);
761 const char *drm_get_tv_subconnector_name(int val
);
762 const char *drm_get_tv_select_name(int val
);
764 int drm_mode_create_dvi_i_properties(struct drm_device
*dev
);
765 int drm_mode_create_tv_properties(struct drm_device
*dev
,
766 unsigned int num_modes
,
767 const char * const modes
[]);
768 int drm_mode_create_scaling_mode_property(struct drm_device
*dev
);
769 int drm_mode_create_aspect_ratio_property(struct drm_device
*dev
);
770 int drm_mode_create_suggested_offset_properties(struct drm_device
*dev
);
772 int drm_mode_connector_set_path_property(struct drm_connector
*connector
,
774 int drm_mode_connector_set_tile_property(struct drm_connector
*connector
);
775 int drm_mode_connector_update_edid_property(struct drm_connector
*connector
,
776 const struct edid
*edid
);
779 * drm_for_each_connector - iterate over all connectors
780 * @connector: the loop cursor
781 * @dev: the DRM device
783 * Iterate over all connectors of @dev.
785 #define drm_for_each_connector(connector, dev) \
786 for (assert_drm_connector_list_read_locked(&(dev)->mode_config), \
787 connector = list_first_entry(&(dev)->mode_config.connector_list, \
788 struct drm_connector, head); \
789 &connector->head != (&(dev)->mode_config.connector_list); \
790 connector = list_next_entry(connector, head))