2 * Copyright (c) 2016 Intel Corporation
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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;
43 enum drm_connector_force {
44 DRM_FORCE_UNSPECIFIED,
46 DRM_FORCE_ON, /* force on analog part normally */
47 DRM_FORCE_ON_DIGITAL, /* for DVI-I use digital connector */
51 * enum drm_connector_status - status for a &drm_connector
53 * This enum is used to track the connector status. There are no separate
54 * #defines for the uapi!
56 enum drm_connector_status {
58 * @connector_status_connected: The connector is definitely connected to
59 * a sink device, and can be enabled.
61 connector_status_connected = 1,
63 * @connector_status_disconnected: The connector isn't connected to a
64 * sink device which can be autodetect. For digital outputs like DP or
65 * HDMI (which can be realiable probed) this means there's really
66 * nothing there. It is driver-dependent whether a connector with this
67 * status can be lit up or not.
69 connector_status_disconnected = 2,
71 * @connector_status_unknown: The connector's status could not be
72 * reliably detected. This happens when probing would either cause
73 * flicker (like load-detection when the connector is in use), or when a
74 * hardware resource isn't available (like when load-detection needs a
75 * free CRTC). It should be possible to light up the connector with one
76 * of the listed fallback modes. For default configuration userspace
77 * should only try to light up connectors with unknown status when
78 * there's not connector with @connector_status_connected.
80 connector_status_unknown = 3,
85 SubPixelHorizontalRGB,
86 SubPixelHorizontalBGR,
93 * struct drm_display_info - runtime data about the connected sink
95 * Describes a given display (e.g. CRT or flat panel) and its limitations. For
96 * fixed display sinks like built-in panels there's not much difference between
97 * this and struct &drm_connector. But for sinks with a real cable this
98 * structure is meant to describe all the things at the other end of the cable.
100 * For sinks which provide an EDID this can be filled out by calling
101 * drm_add_edid_modes().
103 struct drm_display_info {
105 * @name: Name of the display.
107 char name[DRM_DISPLAY_INFO_LEN];
110 * @width_mm: Physical width in mm.
112 unsigned int width_mm;
114 * @height_mm: Physical height in mm.
116 unsigned int height_mm;
119 * @pixel_clock: Maximum pixel clock supported by the sink, in units of
120 * 100Hz. This mismatches the clok in &drm_display_mode (which is in
121 * kHZ), because that's what the EDID uses as base unit.
123 unsigned int pixel_clock;
125 * @bpc: Maximum bits per color channel. Used by HDMI and DP outputs.
130 * @subpixel_order: Subpixel order of LCD panels.
132 enum subpixel_order subpixel_order;
134 #define DRM_COLOR_FORMAT_RGB444 (1<<0)
135 #define DRM_COLOR_FORMAT_YCRCB444 (1<<1)
136 #define DRM_COLOR_FORMAT_YCRCB422 (1<<2)
139 * @color_formats: HDMI Color formats, selects between RGB and YCrCb
140 * modes. Used DRM_COLOR_FORMAT\_ defines, which are _not_ the same ones
141 * as used to describe the pixel format in framebuffers, and also don't
142 * match the formats in @bus_formats which are shared with v4l.
147 * @bus_formats: Pixel data format on the wire, somewhat redundant with
148 * @color_formats. Array of size @num_bus_formats encoded using
149 * MEDIA_BUS_FMT\_ defines shared with v4l and media drivers.
151 const u32 *bus_formats;
153 * @num_bus_formats: Size of @bus_formats array.
155 unsigned int num_bus_formats;
157 #define DRM_BUS_FLAG_DE_LOW (1<<0)
158 #define DRM_BUS_FLAG_DE_HIGH (1<<1)
159 /* drive data on pos. edge */
160 #define DRM_BUS_FLAG_PIXDATA_POSEDGE (1<<2)
161 /* drive data on neg. edge */
162 #define DRM_BUS_FLAG_PIXDATA_NEGEDGE (1<<3)
165 * @bus_flags: Additional information (like pixel signal polarity) for
166 * the pixel data on the bus, using DRM_BUS_FLAGS\_ defines.
171 * @max_tmds_clock: Maximum TMDS clock rate supported by the
172 * sink in kHz. 0 means undefined.
177 * @dvi_dual: Dual-link DVI sink?
182 * @edid_hdmi_dc_modes: Mask of supported hdmi deep color modes. Even
183 * more stuff redundant with @bus_formats.
185 u8 edid_hdmi_dc_modes;
188 * @cea_rev: CEA revision of the HDMI sink.
193 int drm_display_info_set_bus_formats(struct drm_display_info *info,
195 unsigned int num_formats);
198 * struct drm_tv_connector_state - TV connector related states
199 * @subconnector: selected subconnector
200 * @margins: left/right/top/bottom margins
202 * @brightness: brightness in percent
203 * @contrast: contrast in percent
204 * @flicker_reduction: flicker reduction in percent
205 * @overscan: overscan in percent
206 * @saturation: saturation in percent
207 * @hue: hue in percent
209 struct drm_tv_connector_state {
210 enum drm_mode_subconnector subconnector;
218 unsigned int brightness;
219 unsigned int contrast;
220 unsigned int flicker_reduction;
221 unsigned int overscan;
222 unsigned int saturation;
227 * struct drm_connector_state - mutable connector state
228 * @connector: backpointer to the connector
229 * @best_encoder: can be used by helpers and drivers to select the encoder
230 * @state: backpointer to global drm_atomic_state
231 * @tv: TV connector state
233 struct drm_connector_state {
234 struct drm_connector *connector;
237 * @crtc: CRTC to connect connector to, NULL if disabled.
239 * Do not change this directly, use drm_atomic_set_crtc_for_connector()
242 struct drm_crtc *crtc;
244 struct drm_encoder *best_encoder;
246 struct drm_atomic_state *state;
248 struct drm_tv_connector_state tv;
252 * struct drm_connector_funcs - control connectors on a given device
254 * Each CRTC may have one or more connectors attached to it. The functions
255 * below allow the core DRM code to control connectors, enumerate available modes,
258 struct drm_connector_funcs {
262 * Legacy entry point to set the per-connector DPMS state. Legacy DPMS
263 * is exposed as a standard property on the connector, but diverted to
264 * this callback in the drm core. Note that atomic drivers don't
265 * implement the 4 level DPMS support on the connector any more, but
266 * instead only have an on/off "ACTIVE" property on the CRTC object.
268 * Drivers implementing atomic modeset should use
269 * drm_atomic_helper_connector_dpms() to implement this hook.
273 * 0 on success or a negative error code on failure.
275 int (*dpms)(struct drm_connector *connector, int mode);
280 * Reset connector hardware and software state to off. This function isn't
281 * called by the core directly, only through drm_mode_config_reset().
282 * It's not a helper hook only for historical reasons.
284 * Atomic drivers can use drm_atomic_helper_connector_reset() to reset
285 * atomic state using this hook.
287 void (*reset)(struct drm_connector *connector);
292 * Check to see if anything is attached to the connector. The parameter
293 * force is set to false whilst polling, true when checking the
294 * connector due to a user request. force can be used by the driver to
295 * avoid expensive, destructive operations during automated probing.
297 * This callback is optional, if not implemented the connector will be
298 * considered as always being attached.
302 * Note that this hook is only called by the probe helper. It's not in
303 * the helper library vtable purely for historical reasons. The only DRM
304 * core entry point to probe connector state is @fill_modes.
308 * drm_connector_status indicating the connector's status.
310 enum drm_connector_status (*detect)(struct drm_connector *connector,
316 * This function is called to update internal encoder state when the
317 * connector is forced to a certain state by userspace, either through
318 * the sysfs interfaces or on the kernel cmdline. In that case the
319 * @detect callback isn't called.
323 * Note that this hook is only called by the probe helper. It's not in
324 * the helper library vtable purely for historical reasons. The only DRM
325 * core entry point to probe connector state is @fill_modes.
327 void (*force)(struct drm_connector *connector);
332 * Entry point for output detection and basic mode validation. The
333 * driver should reprobe the output if needed (e.g. when hotplug
334 * handling is unreliable), add all detected modes to connector->modes
335 * and filter out any the device can't support in any configuration. It
336 * also needs to filter out any modes wider or higher than the
337 * parameters max_width and max_height indicate.
339 * The drivers must also prune any modes no longer valid from
340 * connector->modes. Furthermore it must update connector->status and
341 * connector->edid. If no EDID has been received for this output
342 * connector->edid must be NULL.
344 * Drivers using the probe helpers should use
345 * drm_helper_probe_single_connector_modes() or
346 * drm_helper_probe_single_connector_modes_nomerge() to implement this
351 * The number of modes detected and filled into connector->modes.
353 int (*fill_modes)(struct drm_connector *connector, uint32_t max_width, uint32_t max_height);
358 * This is the legacy entry point to update a property attached to the
361 * Drivers implementing atomic modeset should use
362 * drm_atomic_helper_connector_set_property() to implement this hook.
364 * This callback is optional if the driver does not support any legacy
365 * driver-private properties.
369 * 0 on success or a negative error code on failure.
371 int (*set_property)(struct drm_connector *connector, struct drm_property *property,
377 * This optional hook can be used to register additional userspace
378 * interfaces attached to the connector, light backlight control, i2c,
379 * DP aux or similar interfaces. It is called late in the driver load
380 * sequence from drm_connector_register() when registering all the
381 * core drm connector interfaces. Everything added from this callback
382 * should be unregistered in the early_unregister callback.
386 * 0 on success, or a negative error code on failure.
388 int (*late_register)(struct drm_connector *connector);
393 * This optional hook should be used to unregister the additional
394 * userspace interfaces attached to the connector from
395 * late_register(). It is called from drm_connector_unregister(),
396 * early in the driver unload sequence to disable userspace access
397 * before data structures are torndown.
399 void (*early_unregister)(struct drm_connector *connector);
404 * Clean up connector resources. This is called at driver unload time
405 * through drm_mode_config_cleanup(). It can also be called at runtime
406 * when a connector is being hot-unplugged for drivers that support
407 * connector hotplugging (e.g. DisplayPort MST).
409 void (*destroy)(struct drm_connector *connector);
412 * @atomic_duplicate_state:
414 * Duplicate the current atomic state for this connector and return it.
415 * The core and helpers guarantee that any atomic state duplicated with
416 * this hook and still owned by the caller (i.e. not transferred to the
417 * driver by calling ->atomic_commit() from struct
418 * &drm_mode_config_funcs) will be cleaned up by calling the
419 * @atomic_destroy_state hook in this structure.
421 * Atomic drivers which don't subclass struct &drm_connector_state should use
422 * drm_atomic_helper_connector_duplicate_state(). Drivers that subclass the
423 * state structure to extend it with driver-private state should use
424 * __drm_atomic_helper_connector_duplicate_state() to make sure shared state is
425 * duplicated in a consistent fashion across drivers.
427 * It is an error to call this hook before connector->state has been
428 * initialized correctly.
432 * If the duplicate state references refcounted resources this hook must
433 * acquire a reference for each of them. The driver must release these
434 * references again in @atomic_destroy_state.
438 * Duplicated atomic state or NULL when the allocation failed.
440 struct drm_connector_state *(*atomic_duplicate_state)(struct drm_connector *connector);
443 * @atomic_destroy_state:
445 * Destroy a state duplicated with @atomic_duplicate_state and release
446 * or unreference all resources it references
448 void (*atomic_destroy_state)(struct drm_connector *connector,
449 struct drm_connector_state *state);
452 * @atomic_set_property:
454 * Decode a driver-private property value and store the decoded value
455 * into the passed-in state structure. Since the atomic core decodes all
456 * standardized properties (even for extensions beyond the core set of
457 * properties which might not be implemented by all drivers) this
458 * requires drivers to subclass the state structure.
460 * Such driver-private properties should really only be implemented for
461 * truly hardware/vendor specific state. Instead it is preferred to
462 * standardize atomic extension and decode the properties used to expose
463 * such an extension in the core.
465 * Do not call this function directly, use
466 * drm_atomic_connector_set_property() instead.
468 * This callback is optional if the driver does not support any
469 * driver-private atomic properties.
473 * This function is called in the state assembly phase of atomic
474 * modesets, which can be aborted for any reason (including on
475 * userspace's request to just check whether a configuration would be
476 * possible). Drivers MUST NOT touch any persistent state (hardware or
477 * software) or data structures except the passed in @state parameter.
479 * Also since userspace controls in which order properties are set this
480 * function must not do any input validation (since the state update is
481 * incomplete and hence likely inconsistent). Instead any such input
482 * validation must be done in the various atomic_check callbacks.
486 * 0 if the property has been found, -EINVAL if the property isn't
487 * implemented by the driver (which shouldn't ever happen, the core only
488 * asks for properties attached to this connector). No other validation
489 * is allowed by the driver. The core already checks that the property
490 * value is within the range (integer, valid enum value, ...) the driver
491 * set when registering the property.
493 int (*atomic_set_property)(struct drm_connector *connector,
494 struct drm_connector_state *state,
495 struct drm_property *property,
499 * @atomic_get_property:
501 * Reads out the decoded driver-private property. This is used to
502 * implement the GETCONNECTOR IOCTL.
504 * Do not call this function directly, use
505 * drm_atomic_connector_get_property() instead.
507 * This callback is optional if the driver does not support any
508 * driver-private atomic properties.
512 * 0 on success, -EINVAL if the property isn't implemented by the
513 * driver (which shouldn't ever happen, the core only asks for
514 * properties attached to this connector).
516 int (*atomic_get_property)(struct drm_connector *connector,
517 const struct drm_connector_state *state,
518 struct drm_property *property,
522 * @atomic_print_state:
524 * If driver subclasses struct &drm_connector_state, it should implement
525 * this optional hook for printing additional driver specific state.
527 * Do not call this directly, use drm_atomic_connector_print_state()
530 void (*atomic_print_state)(struct drm_printer *p,
531 const struct drm_connector_state *state);
534 /* mode specified on the command line */
535 struct drm_cmdline_mode {
537 bool refresh_specified;
546 enum drm_connector_force force;
550 * struct drm_connector - central DRM connector control structure
551 * @dev: parent DRM device
552 * @kdev: kernel device for sysfs attributes
553 * @attr: sysfs attributes
554 * @head: list management
555 * @base: base KMS object
556 * @name: human readable name, can be overwritten by the driver
557 * @connector_type: one of the DRM_MODE_CONNECTOR_<foo> types from drm_mode.h
558 * @connector_type_id: index into connector type enum
559 * @interlace_allowed: can this connector handle interlaced modes?
560 * @doublescan_allowed: can this connector handle doublescan?
561 * @stereo_allowed: can this connector handle stereo modes?
562 * @registered: is this connector exposed (registered) with userspace?
563 * @modes: modes available on this connector (from fill_modes() + user)
564 * @status: one of the drm_connector_status enums (connected, not, or unknown)
565 * @probed_modes: list of modes derived directly from the display
566 * @funcs: connector control functions
567 * @edid_blob_ptr: DRM property containing EDID if present
568 * @properties: property tracking for this connector
569 * @dpms: current dpms state
570 * @helper_private: mid-layer private data
571 * @cmdline_mode: mode line parsed from the kernel cmdline for this connector
572 * @force: a DRM_FORCE_<foo> state for forced mode sets
573 * @override_edid: has the EDID been overwritten through debugfs for testing?
574 * @encoder_ids: valid encoders for this connector
575 * @encoder: encoder driving this connector, if any
576 * @eld: EDID-like data, if present
577 * @latency_present: AV delay info from ELD, if found
578 * @video_latency: video latency info from ELD, if found
579 * @audio_latency: audio latency info from ELD, if found
580 * @null_edid_counter: track sinks that give us all zeros for the EDID
581 * @bad_edid_counter: track sinks that give us an EDID with invalid checksum
582 * @edid_corrupt: indicates whether the last read EDID was corrupt
583 * @debugfs_entry: debugfs directory for this connector
584 * @state: current atomic state for this connector
585 * @has_tile: is this connector connected to a tiled monitor
586 * @tile_group: tile group for the connected monitor
587 * @tile_is_single_monitor: whether the tile is one monitor housing
588 * @num_h_tile: number of horizontal tiles in the tile group
589 * @num_v_tile: number of vertical tiles in the tile group
590 * @tile_h_loc: horizontal location of this tile
591 * @tile_v_loc: vertical location of this tile
592 * @tile_h_size: horizontal size of this tile.
593 * @tile_v_size: vertical size of this tile.
595 * Each connector may be connected to one or more CRTCs, or may be clonable by
596 * another connector if they can share a CRTC. Each connector also has a specific
597 * position in the broader display (referred to as a 'screen' though it could
598 * span multiple monitors).
600 struct drm_connector {
601 struct drm_device *dev;
603 struct device_attribute *attr;
604 struct list_head head;
606 struct drm_mode_object base;
611 * @index: Compacted connector index, which matches the position inside
612 * the mode_config.list for drivers not supporting hot-add/removing. Can
613 * be used as an array index. It is invariant over the lifetime of the
619 int connector_type_id;
620 bool interlace_allowed;
621 bool doublescan_allowed;
624 struct list_head modes; /* list of modes on this connector */
626 enum drm_connector_status status;
628 /* these are modes added by probing with DDC or the BIOS */
629 struct list_head probed_modes;
632 * @display_info: Display information is filled from EDID information
633 * when a display is detected. For non hot-pluggable displays such as
634 * flat panels in embedded systems, the driver should initialize the
635 * display_info.width_mm and display_info.height_mm fields with the
636 * physical size of the display.
638 struct drm_display_info display_info;
639 const struct drm_connector_funcs *funcs;
641 struct drm_property_blob *edid_blob_ptr;
642 struct drm_object_properties properties;
647 * DRM blob property data for the DP MST path property.
649 struct drm_property_blob *path_blob_ptr;
654 * DRM blob property data for the tile property (used mostly by DP MST).
655 * This is meant for screens which are driven through separate display
656 * pipelines represented by &drm_crtc, which might not be running with
657 * genlocked clocks. For tiled panels which are genlocked, like
658 * dual-link LVDS or dual-link DSI, the driver should try to not expose
659 * the tiling and virtualize both &drm_crtc and &drm_plane if needed.
661 struct drm_property_blob *tile_blob_ptr;
663 /* should we poll this connector for connects and disconnects */
664 /* hot plug detectable */
665 #define DRM_CONNECTOR_POLL_HPD (1 << 0)
666 /* poll for connections */
667 #define DRM_CONNECTOR_POLL_CONNECT (1 << 1)
668 /* can cleanly poll for disconnections without flickering the screen */
669 /* DACs should rarely do this without a lot of testing */
670 #define DRM_CONNECTOR_POLL_DISCONNECT (1 << 2)
675 * Connector polling mode, a combination of
677 * DRM_CONNECTOR_POLL_HPD
678 * The connector generates hotplug events and doesn't need to be
679 * periodically polled. The CONNECT and DISCONNECT flags must not
680 * be set together with the HPD flag.
682 * DRM_CONNECTOR_POLL_CONNECT
683 * Periodically poll the connector for connection.
685 * DRM_CONNECTOR_POLL_DISCONNECT
686 * Periodically poll the connector for disconnection.
688 * Set to 0 for connectors that don't support connection status
693 /* requested DPMS state */
696 const struct drm_connector_helper_funcs *helper_private;
698 /* forced on connector */
699 struct drm_cmdline_mode cmdline_mode;
700 enum drm_connector_force force;
703 #define DRM_CONNECTOR_MAX_ENCODER 3
704 uint32_t encoder_ids[DRM_CONNECTOR_MAX_ENCODER];
705 struct drm_encoder *encoder; /* currently active encoder */
707 #define MAX_ELD_BYTES 128
709 uint8_t eld[MAX_ELD_BYTES];
710 bool latency_present[2];
711 int video_latency[2]; /* [0]: progressive, [1]: interlaced */
712 int audio_latency[2];
713 int null_edid_counter; /* needed to workaround some HW bugs where we get all 0s */
714 unsigned bad_edid_counter;
716 /* Flag for raw EDID header corruption - used in Displayport
717 * compliance testing - * Displayport Link CTS Core 1.2 rev1.1 4.2.2.6
721 struct dentry *debugfs_entry;
723 struct drm_connector_state *state;
727 struct drm_tile_group *tile_group;
728 bool tile_is_single_monitor;
730 uint8_t num_h_tile, num_v_tile;
731 uint8_t tile_h_loc, tile_v_loc;
732 uint16_t tile_h_size, tile_v_size;
735 #define obj_to_connector(x) container_of(x, struct drm_connector, base)
737 int drm_connector_init(struct drm_device *dev,
738 struct drm_connector *connector,
739 const struct drm_connector_funcs *funcs,
741 int drm_connector_register(struct drm_connector *connector);
742 void drm_connector_unregister(struct drm_connector *connector);
743 int drm_mode_connector_attach_encoder(struct drm_connector *connector,
744 struct drm_encoder *encoder);
746 void drm_connector_cleanup(struct drm_connector *connector);
747 static inline unsigned drm_connector_index(struct drm_connector *connector)
749 return connector->index;
753 * drm_connector_lookup - lookup connector object
755 * @id: connector object id
757 * This function looks up the connector object specified by id
758 * add takes a reference to it.
760 static inline struct drm_connector *drm_connector_lookup(struct drm_device *dev,
763 struct drm_mode_object *mo;
764 mo = drm_mode_object_find(dev, id, DRM_MODE_OBJECT_CONNECTOR);
765 return mo ? obj_to_connector(mo) : NULL;
769 * drm_connector_reference - incr the connector refcnt
770 * @connector: connector
772 * This function increments the connector's refcount.
774 static inline void drm_connector_reference(struct drm_connector *connector)
776 drm_mode_object_reference(&connector->base);
780 * drm_connector_unreference - unref a connector
781 * @connector: connector to unref
783 * This function decrements the connector's refcount and frees it if it drops to zero.
785 static inline void drm_connector_unreference(struct drm_connector *connector)
787 drm_mode_object_unreference(&connector->base);
790 const char *drm_get_connector_status_name(enum drm_connector_status status);
791 const char *drm_get_subpixel_order_name(enum subpixel_order order);
792 const char *drm_get_dpms_name(int val);
793 const char *drm_get_dvi_i_subconnector_name(int val);
794 const char *drm_get_dvi_i_select_name(int val);
795 const char *drm_get_tv_subconnector_name(int val);
796 const char *drm_get_tv_select_name(int val);
798 int drm_mode_create_dvi_i_properties(struct drm_device *dev);
799 int drm_mode_create_tv_properties(struct drm_device *dev,
800 unsigned int num_modes,
801 const char * const modes[]);
802 int drm_mode_create_scaling_mode_property(struct drm_device *dev);
803 int drm_mode_create_aspect_ratio_property(struct drm_device *dev);
804 int drm_mode_create_suggested_offset_properties(struct drm_device *dev);
806 int drm_mode_connector_set_path_property(struct drm_connector *connector,
808 int drm_mode_connector_set_tile_property(struct drm_connector *connector);
809 int drm_mode_connector_update_edid_property(struct drm_connector *connector,
810 const struct edid *edid);
813 * struct drm_tile_group - Tile group metadata
814 * @refcount: reference count
816 * @id: tile group id exposed to userspace
817 * @group_data: Sink-private data identifying this group
819 * @group_data corresponds to displayid vend/prod/serial for external screens
822 struct drm_tile_group {
823 struct kref refcount;
824 struct drm_device *dev;
829 struct drm_tile_group *drm_mode_create_tile_group(struct drm_device *dev,
831 struct drm_tile_group *drm_mode_get_tile_group(struct drm_device *dev,
833 void drm_mode_put_tile_group(struct drm_device *dev,
834 struct drm_tile_group *tg);
837 * drm_for_each_connector - iterate over all connectors
838 * @connector: the loop cursor
839 * @dev: the DRM device
841 * Iterate over all connectors of @dev.
843 #define drm_for_each_connector(connector, dev) \
844 for (assert_drm_connector_list_read_locked(&(dev)->mode_config), \
845 connector = list_first_entry(&(dev)->mode_config.connector_list, \
846 struct drm_connector, head); \
847 &connector->head != (&(dev)->mode_config.connector_list); \
848 connector = list_next_entry(connector, head))