xref: /openbmc/linux/drivers/gpu/drm/drm_connector.c (revision f39650de)
1 /*
2  * Copyright (c) 2016 Intel Corporation
3  *
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
7  * notice and this permission notice appear in supporting documentation, and
8  * that the name of the copyright holders not be used in advertising or
9  * publicity pertaining to distribution of the software without specific,
10  * written prior permission.  The copyright holders make no representations
11  * about the suitability of this software for any purpose.  It is provided "as
12  * is" without express or implied warranty.
13  *
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
17  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20  * OF THIS SOFTWARE.
21  */
22 
23 #include <drm/drm_connector.h>
24 #include <drm/drm_edid.h>
25 #include <drm/drm_encoder.h>
26 #include <drm/drm_utils.h>
27 #include <drm/drm_print.h>
28 #include <drm/drm_drv.h>
29 #include <drm/drm_file.h>
30 #include <drm/drm_sysfs.h>
31 
32 #include <linux/uaccess.h>
33 
34 #include "drm_crtc_internal.h"
35 #include "drm_internal.h"
36 
37 /**
38  * DOC: overview
39  *
40  * In DRM connectors are the general abstraction for display sinks, and include
41  * also fixed panels or anything else that can display pixels in some form. As
42  * opposed to all other KMS objects representing hardware (like CRTC, encoder or
43  * plane abstractions) connectors can be hotplugged and unplugged at runtime.
44  * Hence they are reference-counted using drm_connector_get() and
45  * drm_connector_put().
46  *
47  * KMS driver must create, initialize, register and attach at a &struct
48  * drm_connector for each such sink. The instance is created as other KMS
49  * objects and initialized by setting the following fields. The connector is
50  * initialized with a call to drm_connector_init() with a pointer to the
51  * &struct drm_connector_funcs and a connector type, and then exposed to
52  * userspace with a call to drm_connector_register().
53  *
54  * Connectors must be attached to an encoder to be used. For devices that map
55  * connectors to encoders 1:1, the connector should be attached at
56  * initialization time with a call to drm_connector_attach_encoder(). The
57  * driver must also set the &drm_connector.encoder field to point to the
58  * attached encoder.
59  *
60  * For connectors which are not fixed (like built-in panels) the driver needs to
61  * support hotplug notifications. The simplest way to do that is by using the
62  * probe helpers, see drm_kms_helper_poll_init() for connectors which don't have
63  * hardware support for hotplug interrupts. Connectors with hardware hotplug
64  * support can instead use e.g. drm_helper_hpd_irq_event().
65  */
66 
67 struct drm_conn_prop_enum_list {
68 	int type;
69 	const char *name;
70 	struct ida ida;
71 };
72 
73 /*
74  * Connector and encoder types.
75  */
76 static struct drm_conn_prop_enum_list drm_connector_enum_list[] = {
77 	{ DRM_MODE_CONNECTOR_Unknown, "Unknown" },
78 	{ DRM_MODE_CONNECTOR_VGA, "VGA" },
79 	{ DRM_MODE_CONNECTOR_DVII, "DVI-I" },
80 	{ DRM_MODE_CONNECTOR_DVID, "DVI-D" },
81 	{ DRM_MODE_CONNECTOR_DVIA, "DVI-A" },
82 	{ DRM_MODE_CONNECTOR_Composite, "Composite" },
83 	{ DRM_MODE_CONNECTOR_SVIDEO, "SVIDEO" },
84 	{ DRM_MODE_CONNECTOR_LVDS, "LVDS" },
85 	{ DRM_MODE_CONNECTOR_Component, "Component" },
86 	{ DRM_MODE_CONNECTOR_9PinDIN, "DIN" },
87 	{ DRM_MODE_CONNECTOR_DisplayPort, "DP" },
88 	{ DRM_MODE_CONNECTOR_HDMIA, "HDMI-A" },
89 	{ DRM_MODE_CONNECTOR_HDMIB, "HDMI-B" },
90 	{ DRM_MODE_CONNECTOR_TV, "TV" },
91 	{ DRM_MODE_CONNECTOR_eDP, "eDP" },
92 	{ DRM_MODE_CONNECTOR_VIRTUAL, "Virtual" },
93 	{ DRM_MODE_CONNECTOR_DSI, "DSI" },
94 	{ DRM_MODE_CONNECTOR_DPI, "DPI" },
95 	{ DRM_MODE_CONNECTOR_WRITEBACK, "Writeback" },
96 	{ DRM_MODE_CONNECTOR_SPI, "SPI" },
97 	{ DRM_MODE_CONNECTOR_USB, "USB" },
98 };
99 
100 void drm_connector_ida_init(void)
101 {
102 	int i;
103 
104 	for (i = 0; i < ARRAY_SIZE(drm_connector_enum_list); i++)
105 		ida_init(&drm_connector_enum_list[i].ida);
106 }
107 
108 void drm_connector_ida_destroy(void)
109 {
110 	int i;
111 
112 	for (i = 0; i < ARRAY_SIZE(drm_connector_enum_list); i++)
113 		ida_destroy(&drm_connector_enum_list[i].ida);
114 }
115 
116 /**
117  * drm_get_connector_type_name - return a string for connector type
118  * @type: The connector type (DRM_MODE_CONNECTOR_*)
119  *
120  * Returns: the name of the connector type, or NULL if the type is not valid.
121  */
122 const char *drm_get_connector_type_name(unsigned int type)
123 {
124 	if (type < ARRAY_SIZE(drm_connector_enum_list))
125 		return drm_connector_enum_list[type].name;
126 
127 	return NULL;
128 }
129 EXPORT_SYMBOL(drm_get_connector_type_name);
130 
131 /**
132  * drm_connector_get_cmdline_mode - reads the user's cmdline mode
133  * @connector: connector to query
134  *
135  * The kernel supports per-connector configuration of its consoles through
136  * use of the video= parameter. This function parses that option and
137  * extracts the user's specified mode (or enable/disable status) for a
138  * particular connector. This is typically only used during the early fbdev
139  * setup.
140  */
141 static void drm_connector_get_cmdline_mode(struct drm_connector *connector)
142 {
143 	struct drm_cmdline_mode *mode = &connector->cmdline_mode;
144 	char *option = NULL;
145 
146 	if (fb_get_options(connector->name, &option))
147 		return;
148 
149 	if (!drm_mode_parse_command_line_for_connector(option,
150 						       connector,
151 						       mode))
152 		return;
153 
154 	if (mode->force) {
155 		DRM_INFO("forcing %s connector %s\n", connector->name,
156 			 drm_get_connector_force_name(mode->force));
157 		connector->force = mode->force;
158 	}
159 
160 	if (mode->panel_orientation != DRM_MODE_PANEL_ORIENTATION_UNKNOWN) {
161 		DRM_INFO("cmdline forces connector %s panel_orientation to %d\n",
162 			 connector->name, mode->panel_orientation);
163 		drm_connector_set_panel_orientation(connector,
164 						    mode->panel_orientation);
165 	}
166 
167 	DRM_DEBUG_KMS("cmdline mode for connector %s %s %dx%d@%dHz%s%s%s\n",
168 		      connector->name, mode->name,
169 		      mode->xres, mode->yres,
170 		      mode->refresh_specified ? mode->refresh : 60,
171 		      mode->rb ? " reduced blanking" : "",
172 		      mode->margins ? " with margins" : "",
173 		      mode->interlace ?  " interlaced" : "");
174 }
175 
176 static void drm_connector_free(struct kref *kref)
177 {
178 	struct drm_connector *connector =
179 		container_of(kref, struct drm_connector, base.refcount);
180 	struct drm_device *dev = connector->dev;
181 
182 	drm_mode_object_unregister(dev, &connector->base);
183 	connector->funcs->destroy(connector);
184 }
185 
186 void drm_connector_free_work_fn(struct work_struct *work)
187 {
188 	struct drm_connector *connector, *n;
189 	struct drm_device *dev =
190 		container_of(work, struct drm_device, mode_config.connector_free_work);
191 	struct drm_mode_config *config = &dev->mode_config;
192 	unsigned long flags;
193 	struct llist_node *freed;
194 
195 	spin_lock_irqsave(&config->connector_list_lock, flags);
196 	freed = llist_del_all(&config->connector_free_list);
197 	spin_unlock_irqrestore(&config->connector_list_lock, flags);
198 
199 	llist_for_each_entry_safe(connector, n, freed, free_node) {
200 		drm_mode_object_unregister(dev, &connector->base);
201 		connector->funcs->destroy(connector);
202 	}
203 }
204 
205 /**
206  * drm_connector_init - Init a preallocated connector
207  * @dev: DRM device
208  * @connector: the connector to init
209  * @funcs: callbacks for this connector
210  * @connector_type: user visible type of the connector
211  *
212  * Initialises a preallocated connector. Connectors should be
213  * subclassed as part of driver connector objects.
214  *
215  * Returns:
216  * Zero on success, error code on failure.
217  */
218 int drm_connector_init(struct drm_device *dev,
219 		       struct drm_connector *connector,
220 		       const struct drm_connector_funcs *funcs,
221 		       int connector_type)
222 {
223 	struct drm_mode_config *config = &dev->mode_config;
224 	int ret;
225 	struct ida *connector_ida =
226 		&drm_connector_enum_list[connector_type].ida;
227 
228 	WARN_ON(drm_drv_uses_atomic_modeset(dev) &&
229 		(!funcs->atomic_destroy_state ||
230 		 !funcs->atomic_duplicate_state));
231 
232 	ret = __drm_mode_object_add(dev, &connector->base,
233 				    DRM_MODE_OBJECT_CONNECTOR,
234 				    false, drm_connector_free);
235 	if (ret)
236 		return ret;
237 
238 	connector->base.properties = &connector->properties;
239 	connector->dev = dev;
240 	connector->funcs = funcs;
241 
242 	/* connector index is used with 32bit bitmasks */
243 	ret = ida_simple_get(&config->connector_ida, 0, 32, GFP_KERNEL);
244 	if (ret < 0) {
245 		DRM_DEBUG_KMS("Failed to allocate %s connector index: %d\n",
246 			      drm_connector_enum_list[connector_type].name,
247 			      ret);
248 		goto out_put;
249 	}
250 	connector->index = ret;
251 	ret = 0;
252 
253 	connector->connector_type = connector_type;
254 	connector->connector_type_id =
255 		ida_simple_get(connector_ida, 1, 0, GFP_KERNEL);
256 	if (connector->connector_type_id < 0) {
257 		ret = connector->connector_type_id;
258 		goto out_put_id;
259 	}
260 	connector->name =
261 		kasprintf(GFP_KERNEL, "%s-%d",
262 			  drm_connector_enum_list[connector_type].name,
263 			  connector->connector_type_id);
264 	if (!connector->name) {
265 		ret = -ENOMEM;
266 		goto out_put_type_id;
267 	}
268 
269 	INIT_LIST_HEAD(&connector->probed_modes);
270 	INIT_LIST_HEAD(&connector->modes);
271 	mutex_init(&connector->mutex);
272 	connector->edid_blob_ptr = NULL;
273 	connector->epoch_counter = 0;
274 	connector->tile_blob_ptr = NULL;
275 	connector->status = connector_status_unknown;
276 	connector->display_info.panel_orientation =
277 		DRM_MODE_PANEL_ORIENTATION_UNKNOWN;
278 
279 	drm_connector_get_cmdline_mode(connector);
280 
281 	/* We should add connectors at the end to avoid upsetting the connector
282 	 * index too much. */
283 	spin_lock_irq(&config->connector_list_lock);
284 	list_add_tail(&connector->head, &config->connector_list);
285 	config->num_connector++;
286 	spin_unlock_irq(&config->connector_list_lock);
287 
288 	if (connector_type != DRM_MODE_CONNECTOR_VIRTUAL &&
289 	    connector_type != DRM_MODE_CONNECTOR_WRITEBACK)
290 		drm_connector_attach_edid_property(connector);
291 
292 	drm_object_attach_property(&connector->base,
293 				      config->dpms_property, 0);
294 
295 	drm_object_attach_property(&connector->base,
296 				   config->link_status_property,
297 				   0);
298 
299 	drm_object_attach_property(&connector->base,
300 				   config->non_desktop_property,
301 				   0);
302 	drm_object_attach_property(&connector->base,
303 				   config->tile_property,
304 				   0);
305 
306 	if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
307 		drm_object_attach_property(&connector->base, config->prop_crtc_id, 0);
308 	}
309 
310 	connector->debugfs_entry = NULL;
311 out_put_type_id:
312 	if (ret)
313 		ida_simple_remove(connector_ida, connector->connector_type_id);
314 out_put_id:
315 	if (ret)
316 		ida_simple_remove(&config->connector_ida, connector->index);
317 out_put:
318 	if (ret)
319 		drm_mode_object_unregister(dev, &connector->base);
320 
321 	return ret;
322 }
323 EXPORT_SYMBOL(drm_connector_init);
324 
325 /**
326  * drm_connector_init_with_ddc - Init a preallocated connector
327  * @dev: DRM device
328  * @connector: the connector to init
329  * @funcs: callbacks for this connector
330  * @connector_type: user visible type of the connector
331  * @ddc: pointer to the associated ddc adapter
332  *
333  * Initialises a preallocated connector. Connectors should be
334  * subclassed as part of driver connector objects.
335  *
336  * Ensures that the ddc field of the connector is correctly set.
337  *
338  * Returns:
339  * Zero on success, error code on failure.
340  */
341 int drm_connector_init_with_ddc(struct drm_device *dev,
342 				struct drm_connector *connector,
343 				const struct drm_connector_funcs *funcs,
344 				int connector_type,
345 				struct i2c_adapter *ddc)
346 {
347 	int ret;
348 
349 	ret = drm_connector_init(dev, connector, funcs, connector_type);
350 	if (ret)
351 		return ret;
352 
353 	/* provide ddc symlink in sysfs */
354 	connector->ddc = ddc;
355 
356 	return ret;
357 }
358 EXPORT_SYMBOL(drm_connector_init_with_ddc);
359 
360 /**
361  * drm_connector_attach_edid_property - attach edid property.
362  * @connector: the connector
363  *
364  * Some connector types like DRM_MODE_CONNECTOR_VIRTUAL do not get a
365  * edid property attached by default.  This function can be used to
366  * explicitly enable the edid property in these cases.
367  */
368 void drm_connector_attach_edid_property(struct drm_connector *connector)
369 {
370 	struct drm_mode_config *config = &connector->dev->mode_config;
371 
372 	drm_object_attach_property(&connector->base,
373 				   config->edid_property,
374 				   0);
375 }
376 EXPORT_SYMBOL(drm_connector_attach_edid_property);
377 
378 /**
379  * drm_connector_attach_encoder - attach a connector to an encoder
380  * @connector: connector to attach
381  * @encoder: encoder to attach @connector to
382  *
383  * This function links up a connector to an encoder. Note that the routing
384  * restrictions between encoders and crtcs are exposed to userspace through the
385  * possible_clones and possible_crtcs bitmasks.
386  *
387  * Returns:
388  * Zero on success, negative errno on failure.
389  */
390 int drm_connector_attach_encoder(struct drm_connector *connector,
391 				 struct drm_encoder *encoder)
392 {
393 	/*
394 	 * In the past, drivers have attempted to model the static association
395 	 * of connector to encoder in simple connector/encoder devices using a
396 	 * direct assignment of connector->encoder = encoder. This connection
397 	 * is a logical one and the responsibility of the core, so drivers are
398 	 * expected not to mess with this.
399 	 *
400 	 * Note that the error return should've been enough here, but a large
401 	 * majority of drivers ignores the return value, so add in a big WARN
402 	 * to get people's attention.
403 	 */
404 	if (WARN_ON(connector->encoder))
405 		return -EINVAL;
406 
407 	connector->possible_encoders |= drm_encoder_mask(encoder);
408 
409 	return 0;
410 }
411 EXPORT_SYMBOL(drm_connector_attach_encoder);
412 
413 /**
414  * drm_connector_has_possible_encoder - check if the connector and encoder are
415  * associated with each other
416  * @connector: the connector
417  * @encoder: the encoder
418  *
419  * Returns:
420  * True if @encoder is one of the possible encoders for @connector.
421  */
422 bool drm_connector_has_possible_encoder(struct drm_connector *connector,
423 					struct drm_encoder *encoder)
424 {
425 	return connector->possible_encoders & drm_encoder_mask(encoder);
426 }
427 EXPORT_SYMBOL(drm_connector_has_possible_encoder);
428 
429 static void drm_mode_remove(struct drm_connector *connector,
430 			    struct drm_display_mode *mode)
431 {
432 	list_del(&mode->head);
433 	drm_mode_destroy(connector->dev, mode);
434 }
435 
436 /**
437  * drm_connector_cleanup - cleans up an initialised connector
438  * @connector: connector to cleanup
439  *
440  * Cleans up the connector but doesn't free the object.
441  */
442 void drm_connector_cleanup(struct drm_connector *connector)
443 {
444 	struct drm_device *dev = connector->dev;
445 	struct drm_display_mode *mode, *t;
446 
447 	/* The connector should have been removed from userspace long before
448 	 * it is finally destroyed.
449 	 */
450 	if (WARN_ON(connector->registration_state ==
451 		    DRM_CONNECTOR_REGISTERED))
452 		drm_connector_unregister(connector);
453 
454 	if (connector->tile_group) {
455 		drm_mode_put_tile_group(dev, connector->tile_group);
456 		connector->tile_group = NULL;
457 	}
458 
459 	list_for_each_entry_safe(mode, t, &connector->probed_modes, head)
460 		drm_mode_remove(connector, mode);
461 
462 	list_for_each_entry_safe(mode, t, &connector->modes, head)
463 		drm_mode_remove(connector, mode);
464 
465 	ida_simple_remove(&drm_connector_enum_list[connector->connector_type].ida,
466 			  connector->connector_type_id);
467 
468 	ida_simple_remove(&dev->mode_config.connector_ida,
469 			  connector->index);
470 
471 	kfree(connector->display_info.bus_formats);
472 	drm_mode_object_unregister(dev, &connector->base);
473 	kfree(connector->name);
474 	connector->name = NULL;
475 	spin_lock_irq(&dev->mode_config.connector_list_lock);
476 	list_del(&connector->head);
477 	dev->mode_config.num_connector--;
478 	spin_unlock_irq(&dev->mode_config.connector_list_lock);
479 
480 	WARN_ON(connector->state && !connector->funcs->atomic_destroy_state);
481 	if (connector->state && connector->funcs->atomic_destroy_state)
482 		connector->funcs->atomic_destroy_state(connector,
483 						       connector->state);
484 
485 	mutex_destroy(&connector->mutex);
486 
487 	memset(connector, 0, sizeof(*connector));
488 }
489 EXPORT_SYMBOL(drm_connector_cleanup);
490 
491 /**
492  * drm_connector_register - register a connector
493  * @connector: the connector to register
494  *
495  * Register userspace interfaces for a connector. Only call this for connectors
496  * which can be hotplugged after drm_dev_register() has been called already,
497  * e.g. DP MST connectors. All other connectors will be registered automatically
498  * when calling drm_dev_register().
499  *
500  * Returns:
501  * Zero on success, error code on failure.
502  */
503 int drm_connector_register(struct drm_connector *connector)
504 {
505 	int ret = 0;
506 
507 	if (!connector->dev->registered)
508 		return 0;
509 
510 	mutex_lock(&connector->mutex);
511 	if (connector->registration_state != DRM_CONNECTOR_INITIALIZING)
512 		goto unlock;
513 
514 	ret = drm_sysfs_connector_add(connector);
515 	if (ret)
516 		goto unlock;
517 
518 	drm_debugfs_connector_add(connector);
519 
520 	if (connector->funcs->late_register) {
521 		ret = connector->funcs->late_register(connector);
522 		if (ret)
523 			goto err_debugfs;
524 	}
525 
526 	drm_mode_object_register(connector->dev, &connector->base);
527 
528 	connector->registration_state = DRM_CONNECTOR_REGISTERED;
529 
530 	/* Let userspace know we have a new connector */
531 	drm_sysfs_hotplug_event(connector->dev);
532 
533 	goto unlock;
534 
535 err_debugfs:
536 	drm_debugfs_connector_remove(connector);
537 	drm_sysfs_connector_remove(connector);
538 unlock:
539 	mutex_unlock(&connector->mutex);
540 	return ret;
541 }
542 EXPORT_SYMBOL(drm_connector_register);
543 
544 /**
545  * drm_connector_unregister - unregister a connector
546  * @connector: the connector to unregister
547  *
548  * Unregister userspace interfaces for a connector. Only call this for
549  * connectors which have registered explicitly by calling drm_dev_register(),
550  * since connectors are unregistered automatically when drm_dev_unregister() is
551  * called.
552  */
553 void drm_connector_unregister(struct drm_connector *connector)
554 {
555 	mutex_lock(&connector->mutex);
556 	if (connector->registration_state != DRM_CONNECTOR_REGISTERED) {
557 		mutex_unlock(&connector->mutex);
558 		return;
559 	}
560 
561 	if (connector->funcs->early_unregister)
562 		connector->funcs->early_unregister(connector);
563 
564 	drm_sysfs_connector_remove(connector);
565 	drm_debugfs_connector_remove(connector);
566 
567 	connector->registration_state = DRM_CONNECTOR_UNREGISTERED;
568 	mutex_unlock(&connector->mutex);
569 }
570 EXPORT_SYMBOL(drm_connector_unregister);
571 
572 void drm_connector_unregister_all(struct drm_device *dev)
573 {
574 	struct drm_connector *connector;
575 	struct drm_connector_list_iter conn_iter;
576 
577 	drm_connector_list_iter_begin(dev, &conn_iter);
578 	drm_for_each_connector_iter(connector, &conn_iter)
579 		drm_connector_unregister(connector);
580 	drm_connector_list_iter_end(&conn_iter);
581 }
582 
583 int drm_connector_register_all(struct drm_device *dev)
584 {
585 	struct drm_connector *connector;
586 	struct drm_connector_list_iter conn_iter;
587 	int ret = 0;
588 
589 	drm_connector_list_iter_begin(dev, &conn_iter);
590 	drm_for_each_connector_iter(connector, &conn_iter) {
591 		ret = drm_connector_register(connector);
592 		if (ret)
593 			break;
594 	}
595 	drm_connector_list_iter_end(&conn_iter);
596 
597 	if (ret)
598 		drm_connector_unregister_all(dev);
599 	return ret;
600 }
601 
602 /**
603  * drm_get_connector_status_name - return a string for connector status
604  * @status: connector status to compute name of
605  *
606  * In contrast to the other drm_get_*_name functions this one here returns a
607  * const pointer and hence is threadsafe.
608  */
609 const char *drm_get_connector_status_name(enum drm_connector_status status)
610 {
611 	if (status == connector_status_connected)
612 		return "connected";
613 	else if (status == connector_status_disconnected)
614 		return "disconnected";
615 	else
616 		return "unknown";
617 }
618 EXPORT_SYMBOL(drm_get_connector_status_name);
619 
620 /**
621  * drm_get_connector_force_name - return a string for connector force
622  * @force: connector force to get name of
623  *
624  * Returns: const pointer to name.
625  */
626 const char *drm_get_connector_force_name(enum drm_connector_force force)
627 {
628 	switch (force) {
629 	case DRM_FORCE_UNSPECIFIED:
630 		return "unspecified";
631 	case DRM_FORCE_OFF:
632 		return "off";
633 	case DRM_FORCE_ON:
634 		return "on";
635 	case DRM_FORCE_ON_DIGITAL:
636 		return "digital";
637 	default:
638 		return "unknown";
639 	}
640 }
641 
642 #ifdef CONFIG_LOCKDEP
643 static struct lockdep_map connector_list_iter_dep_map = {
644 	.name = "drm_connector_list_iter"
645 };
646 #endif
647 
648 /**
649  * drm_connector_list_iter_begin - initialize a connector_list iterator
650  * @dev: DRM device
651  * @iter: connector_list iterator
652  *
653  * Sets @iter up to walk the &drm_mode_config.connector_list of @dev. @iter
654  * must always be cleaned up again by calling drm_connector_list_iter_end().
655  * Iteration itself happens using drm_connector_list_iter_next() or
656  * drm_for_each_connector_iter().
657  */
658 void drm_connector_list_iter_begin(struct drm_device *dev,
659 				   struct drm_connector_list_iter *iter)
660 {
661 	iter->dev = dev;
662 	iter->conn = NULL;
663 	lock_acquire_shared_recursive(&connector_list_iter_dep_map, 0, 1, NULL, _RET_IP_);
664 }
665 EXPORT_SYMBOL(drm_connector_list_iter_begin);
666 
667 /*
668  * Extra-safe connector put function that works in any context. Should only be
669  * used from the connector_iter functions, where we never really expect to
670  * actually release the connector when dropping our final reference.
671  */
672 static void
673 __drm_connector_put_safe(struct drm_connector *conn)
674 {
675 	struct drm_mode_config *config = &conn->dev->mode_config;
676 
677 	lockdep_assert_held(&config->connector_list_lock);
678 
679 	if (!refcount_dec_and_test(&conn->base.refcount.refcount))
680 		return;
681 
682 	llist_add(&conn->free_node, &config->connector_free_list);
683 	schedule_work(&config->connector_free_work);
684 }
685 
686 /**
687  * drm_connector_list_iter_next - return next connector
688  * @iter: connector_list iterator
689  *
690  * Returns the next connector for @iter, or NULL when the list walk has
691  * completed.
692  */
693 struct drm_connector *
694 drm_connector_list_iter_next(struct drm_connector_list_iter *iter)
695 {
696 	struct drm_connector *old_conn = iter->conn;
697 	struct drm_mode_config *config = &iter->dev->mode_config;
698 	struct list_head *lhead;
699 	unsigned long flags;
700 
701 	spin_lock_irqsave(&config->connector_list_lock, flags);
702 	lhead = old_conn ? &old_conn->head : &config->connector_list;
703 
704 	do {
705 		if (lhead->next == &config->connector_list) {
706 			iter->conn = NULL;
707 			break;
708 		}
709 
710 		lhead = lhead->next;
711 		iter->conn = list_entry(lhead, struct drm_connector, head);
712 
713 		/* loop until it's not a zombie connector */
714 	} while (!kref_get_unless_zero(&iter->conn->base.refcount));
715 
716 	if (old_conn)
717 		__drm_connector_put_safe(old_conn);
718 	spin_unlock_irqrestore(&config->connector_list_lock, flags);
719 
720 	return iter->conn;
721 }
722 EXPORT_SYMBOL(drm_connector_list_iter_next);
723 
724 /**
725  * drm_connector_list_iter_end - tear down a connector_list iterator
726  * @iter: connector_list iterator
727  *
728  * Tears down @iter and releases any resources (like &drm_connector references)
729  * acquired while walking the list. This must always be called, both when the
730  * iteration completes fully or when it was aborted without walking the entire
731  * list.
732  */
733 void drm_connector_list_iter_end(struct drm_connector_list_iter *iter)
734 {
735 	struct drm_mode_config *config = &iter->dev->mode_config;
736 	unsigned long flags;
737 
738 	iter->dev = NULL;
739 	if (iter->conn) {
740 		spin_lock_irqsave(&config->connector_list_lock, flags);
741 		__drm_connector_put_safe(iter->conn);
742 		spin_unlock_irqrestore(&config->connector_list_lock, flags);
743 	}
744 	lock_release(&connector_list_iter_dep_map, _RET_IP_);
745 }
746 EXPORT_SYMBOL(drm_connector_list_iter_end);
747 
748 static const struct drm_prop_enum_list drm_subpixel_enum_list[] = {
749 	{ SubPixelUnknown, "Unknown" },
750 	{ SubPixelHorizontalRGB, "Horizontal RGB" },
751 	{ SubPixelHorizontalBGR, "Horizontal BGR" },
752 	{ SubPixelVerticalRGB, "Vertical RGB" },
753 	{ SubPixelVerticalBGR, "Vertical BGR" },
754 	{ SubPixelNone, "None" },
755 };
756 
757 /**
758  * drm_get_subpixel_order_name - return a string for a given subpixel enum
759  * @order: enum of subpixel_order
760  *
761  * Note you could abuse this and return something out of bounds, but that
762  * would be a caller error.  No unscrubbed user data should make it here.
763  */
764 const char *drm_get_subpixel_order_name(enum subpixel_order order)
765 {
766 	return drm_subpixel_enum_list[order].name;
767 }
768 EXPORT_SYMBOL(drm_get_subpixel_order_name);
769 
770 static const struct drm_prop_enum_list drm_dpms_enum_list[] = {
771 	{ DRM_MODE_DPMS_ON, "On" },
772 	{ DRM_MODE_DPMS_STANDBY, "Standby" },
773 	{ DRM_MODE_DPMS_SUSPEND, "Suspend" },
774 	{ DRM_MODE_DPMS_OFF, "Off" }
775 };
776 DRM_ENUM_NAME_FN(drm_get_dpms_name, drm_dpms_enum_list)
777 
778 static const struct drm_prop_enum_list drm_link_status_enum_list[] = {
779 	{ DRM_MODE_LINK_STATUS_GOOD, "Good" },
780 	{ DRM_MODE_LINK_STATUS_BAD, "Bad" },
781 };
782 
783 /**
784  * drm_display_info_set_bus_formats - set the supported bus formats
785  * @info: display info to store bus formats in
786  * @formats: array containing the supported bus formats
787  * @num_formats: the number of entries in the fmts array
788  *
789  * Store the supported bus formats in display info structure.
790  * See MEDIA_BUS_FMT_* definitions in include/uapi/linux/media-bus-format.h for
791  * a full list of available formats.
792  */
793 int drm_display_info_set_bus_formats(struct drm_display_info *info,
794 				     const u32 *formats,
795 				     unsigned int num_formats)
796 {
797 	u32 *fmts = NULL;
798 
799 	if (!formats && num_formats)
800 		return -EINVAL;
801 
802 	if (formats && num_formats) {
803 		fmts = kmemdup(formats, sizeof(*formats) * num_formats,
804 			       GFP_KERNEL);
805 		if (!fmts)
806 			return -ENOMEM;
807 	}
808 
809 	kfree(info->bus_formats);
810 	info->bus_formats = fmts;
811 	info->num_bus_formats = num_formats;
812 
813 	return 0;
814 }
815 EXPORT_SYMBOL(drm_display_info_set_bus_formats);
816 
817 /* Optional connector properties. */
818 static const struct drm_prop_enum_list drm_scaling_mode_enum_list[] = {
819 	{ DRM_MODE_SCALE_NONE, "None" },
820 	{ DRM_MODE_SCALE_FULLSCREEN, "Full" },
821 	{ DRM_MODE_SCALE_CENTER, "Center" },
822 	{ DRM_MODE_SCALE_ASPECT, "Full aspect" },
823 };
824 
825 static const struct drm_prop_enum_list drm_aspect_ratio_enum_list[] = {
826 	{ DRM_MODE_PICTURE_ASPECT_NONE, "Automatic" },
827 	{ DRM_MODE_PICTURE_ASPECT_4_3, "4:3" },
828 	{ DRM_MODE_PICTURE_ASPECT_16_9, "16:9" },
829 };
830 
831 static const struct drm_prop_enum_list drm_content_type_enum_list[] = {
832 	{ DRM_MODE_CONTENT_TYPE_NO_DATA, "No Data" },
833 	{ DRM_MODE_CONTENT_TYPE_GRAPHICS, "Graphics" },
834 	{ DRM_MODE_CONTENT_TYPE_PHOTO, "Photo" },
835 	{ DRM_MODE_CONTENT_TYPE_CINEMA, "Cinema" },
836 	{ DRM_MODE_CONTENT_TYPE_GAME, "Game" },
837 };
838 
839 static const struct drm_prop_enum_list drm_panel_orientation_enum_list[] = {
840 	{ DRM_MODE_PANEL_ORIENTATION_NORMAL,	"Normal"	},
841 	{ DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP,	"Upside Down"	},
842 	{ DRM_MODE_PANEL_ORIENTATION_LEFT_UP,	"Left Side Up"	},
843 	{ DRM_MODE_PANEL_ORIENTATION_RIGHT_UP,	"Right Side Up"	},
844 };
845 
846 static const struct drm_prop_enum_list drm_dvi_i_select_enum_list[] = {
847 	{ DRM_MODE_SUBCONNECTOR_Automatic, "Automatic" }, /* DVI-I and TV-out */
848 	{ DRM_MODE_SUBCONNECTOR_DVID,      "DVI-D"     }, /* DVI-I  */
849 	{ DRM_MODE_SUBCONNECTOR_DVIA,      "DVI-A"     }, /* DVI-I  */
850 };
851 DRM_ENUM_NAME_FN(drm_get_dvi_i_select_name, drm_dvi_i_select_enum_list)
852 
853 static const struct drm_prop_enum_list drm_dvi_i_subconnector_enum_list[] = {
854 	{ DRM_MODE_SUBCONNECTOR_Unknown,   "Unknown"   }, /* DVI-I, TV-out and DP */
855 	{ DRM_MODE_SUBCONNECTOR_DVID,      "DVI-D"     }, /* DVI-I  */
856 	{ DRM_MODE_SUBCONNECTOR_DVIA,      "DVI-A"     }, /* DVI-I  */
857 };
858 DRM_ENUM_NAME_FN(drm_get_dvi_i_subconnector_name,
859 		 drm_dvi_i_subconnector_enum_list)
860 
861 static const struct drm_prop_enum_list drm_tv_select_enum_list[] = {
862 	{ DRM_MODE_SUBCONNECTOR_Automatic, "Automatic" }, /* DVI-I and TV-out */
863 	{ DRM_MODE_SUBCONNECTOR_Composite, "Composite" }, /* TV-out */
864 	{ DRM_MODE_SUBCONNECTOR_SVIDEO,    "SVIDEO"    }, /* TV-out */
865 	{ DRM_MODE_SUBCONNECTOR_Component, "Component" }, /* TV-out */
866 	{ DRM_MODE_SUBCONNECTOR_SCART,     "SCART"     }, /* TV-out */
867 };
868 DRM_ENUM_NAME_FN(drm_get_tv_select_name, drm_tv_select_enum_list)
869 
870 static const struct drm_prop_enum_list drm_tv_subconnector_enum_list[] = {
871 	{ DRM_MODE_SUBCONNECTOR_Unknown,   "Unknown"   }, /* DVI-I, TV-out and DP */
872 	{ DRM_MODE_SUBCONNECTOR_Composite, "Composite" }, /* TV-out */
873 	{ DRM_MODE_SUBCONNECTOR_SVIDEO,    "SVIDEO"    }, /* TV-out */
874 	{ DRM_MODE_SUBCONNECTOR_Component, "Component" }, /* TV-out */
875 	{ DRM_MODE_SUBCONNECTOR_SCART,     "SCART"     }, /* TV-out */
876 };
877 DRM_ENUM_NAME_FN(drm_get_tv_subconnector_name,
878 		 drm_tv_subconnector_enum_list)
879 
880 static const struct drm_prop_enum_list drm_dp_subconnector_enum_list[] = {
881 	{ DRM_MODE_SUBCONNECTOR_Unknown,     "Unknown"   }, /* DVI-I, TV-out and DP */
882 	{ DRM_MODE_SUBCONNECTOR_VGA,	     "VGA"       }, /* DP */
883 	{ DRM_MODE_SUBCONNECTOR_DVID,	     "DVI-D"     }, /* DP */
884 	{ DRM_MODE_SUBCONNECTOR_HDMIA,	     "HDMI"      }, /* DP */
885 	{ DRM_MODE_SUBCONNECTOR_DisplayPort, "DP"        }, /* DP */
886 	{ DRM_MODE_SUBCONNECTOR_Wireless,    "Wireless"  }, /* DP */
887 	{ DRM_MODE_SUBCONNECTOR_Native,	     "Native"    }, /* DP */
888 };
889 
890 DRM_ENUM_NAME_FN(drm_get_dp_subconnector_name,
891 		 drm_dp_subconnector_enum_list)
892 
893 static const struct drm_prop_enum_list hdmi_colorspaces[] = {
894 	/* For Default case, driver will set the colorspace */
895 	{ DRM_MODE_COLORIMETRY_DEFAULT, "Default" },
896 	/* Standard Definition Colorimetry based on CEA 861 */
897 	{ DRM_MODE_COLORIMETRY_SMPTE_170M_YCC, "SMPTE_170M_YCC" },
898 	{ DRM_MODE_COLORIMETRY_BT709_YCC, "BT709_YCC" },
899 	/* Standard Definition Colorimetry based on IEC 61966-2-4 */
900 	{ DRM_MODE_COLORIMETRY_XVYCC_601, "XVYCC_601" },
901 	/* High Definition Colorimetry based on IEC 61966-2-4 */
902 	{ DRM_MODE_COLORIMETRY_XVYCC_709, "XVYCC_709" },
903 	/* Colorimetry based on IEC 61966-2-1/Amendment 1 */
904 	{ DRM_MODE_COLORIMETRY_SYCC_601, "SYCC_601" },
905 	/* Colorimetry based on IEC 61966-2-5 [33] */
906 	{ DRM_MODE_COLORIMETRY_OPYCC_601, "opYCC_601" },
907 	/* Colorimetry based on IEC 61966-2-5 */
908 	{ DRM_MODE_COLORIMETRY_OPRGB, "opRGB" },
909 	/* Colorimetry based on ITU-R BT.2020 */
910 	{ DRM_MODE_COLORIMETRY_BT2020_CYCC, "BT2020_CYCC" },
911 	/* Colorimetry based on ITU-R BT.2020 */
912 	{ DRM_MODE_COLORIMETRY_BT2020_RGB, "BT2020_RGB" },
913 	/* Colorimetry based on ITU-R BT.2020 */
914 	{ DRM_MODE_COLORIMETRY_BT2020_YCC, "BT2020_YCC" },
915 	/* Added as part of Additional Colorimetry Extension in 861.G */
916 	{ DRM_MODE_COLORIMETRY_DCI_P3_RGB_D65, "DCI-P3_RGB_D65" },
917 	{ DRM_MODE_COLORIMETRY_DCI_P3_RGB_THEATER, "DCI-P3_RGB_Theater" },
918 };
919 
920 /*
921  * As per DP 1.4a spec, 2.2.5.7.5 VSC SDP Payload for Pixel Encoding/Colorimetry
922  * Format Table 2-120
923  */
924 static const struct drm_prop_enum_list dp_colorspaces[] = {
925 	/* For Default case, driver will set the colorspace */
926 	{ DRM_MODE_COLORIMETRY_DEFAULT, "Default" },
927 	{ DRM_MODE_COLORIMETRY_RGB_WIDE_FIXED, "RGB_Wide_Gamut_Fixed_Point" },
928 	/* Colorimetry based on scRGB (IEC 61966-2-2) */
929 	{ DRM_MODE_COLORIMETRY_RGB_WIDE_FLOAT, "RGB_Wide_Gamut_Floating_Point" },
930 	/* Colorimetry based on IEC 61966-2-5 */
931 	{ DRM_MODE_COLORIMETRY_OPRGB, "opRGB" },
932 	/* Colorimetry based on SMPTE RP 431-2 */
933 	{ DRM_MODE_COLORIMETRY_DCI_P3_RGB_D65, "DCI-P3_RGB_D65" },
934 	/* Colorimetry based on ITU-R BT.2020 */
935 	{ DRM_MODE_COLORIMETRY_BT2020_RGB, "BT2020_RGB" },
936 	{ DRM_MODE_COLORIMETRY_BT601_YCC, "BT601_YCC" },
937 	{ DRM_MODE_COLORIMETRY_BT709_YCC, "BT709_YCC" },
938 	/* Standard Definition Colorimetry based on IEC 61966-2-4 */
939 	{ DRM_MODE_COLORIMETRY_XVYCC_601, "XVYCC_601" },
940 	/* High Definition Colorimetry based on IEC 61966-2-4 */
941 	{ DRM_MODE_COLORIMETRY_XVYCC_709, "XVYCC_709" },
942 	/* Colorimetry based on IEC 61966-2-1/Amendment 1 */
943 	{ DRM_MODE_COLORIMETRY_SYCC_601, "SYCC_601" },
944 	/* Colorimetry based on IEC 61966-2-5 [33] */
945 	{ DRM_MODE_COLORIMETRY_OPYCC_601, "opYCC_601" },
946 	/* Colorimetry based on ITU-R BT.2020 */
947 	{ DRM_MODE_COLORIMETRY_BT2020_CYCC, "BT2020_CYCC" },
948 	/* Colorimetry based on ITU-R BT.2020 */
949 	{ DRM_MODE_COLORIMETRY_BT2020_YCC, "BT2020_YCC" },
950 };
951 
952 /**
953  * DOC: standard connector properties
954  *
955  * DRM connectors have a few standardized properties:
956  *
957  * EDID:
958  * 	Blob property which contains the current EDID read from the sink. This
959  * 	is useful to parse sink identification information like vendor, model
960  * 	and serial. Drivers should update this property by calling
961  * 	drm_connector_update_edid_property(), usually after having parsed
962  * 	the EDID using drm_add_edid_modes(). Userspace cannot change this
963  * 	property.
964  *
965  * 	User-space should not parse the EDID to obtain information exposed via
966  * 	other KMS properties (because the kernel might apply limits, quirks or
967  * 	fixups to the EDID). For instance, user-space should not try to parse
968  * 	mode lists from the EDID.
969  * DPMS:
970  * 	Legacy property for setting the power state of the connector. For atomic
971  * 	drivers this is only provided for backwards compatibility with existing
972  * 	drivers, it remaps to controlling the "ACTIVE" property on the CRTC the
973  * 	connector is linked to. Drivers should never set this property directly,
974  * 	it is handled by the DRM core by calling the &drm_connector_funcs.dpms
975  * 	callback. For atomic drivers the remapping to the "ACTIVE" property is
976  * 	implemented in the DRM core.
977  *
978  * 	Note that this property cannot be set through the MODE_ATOMIC ioctl,
979  * 	userspace must use "ACTIVE" on the CRTC instead.
980  *
981  * 	WARNING:
982  *
983  * 	For userspace also running on legacy drivers the "DPMS" semantics are a
984  * 	lot more complicated. First, userspace cannot rely on the "DPMS" value
985  * 	returned by the GETCONNECTOR actually reflecting reality, because many
986  * 	drivers fail to update it. For atomic drivers this is taken care of in
987  * 	drm_atomic_helper_update_legacy_modeset_state().
988  *
989  * 	The second issue is that the DPMS state is only well-defined when the
990  * 	connector is connected to a CRTC. In atomic the DRM core enforces that
991  * 	"ACTIVE" is off in such a case, no such checks exists for "DPMS".
992  *
993  * 	Finally, when enabling an output using the legacy SETCONFIG ioctl then
994  * 	"DPMS" is forced to ON. But see above, that might not be reflected in
995  * 	the software value on legacy drivers.
996  *
997  * 	Summarizing: Only set "DPMS" when the connector is known to be enabled,
998  * 	assume that a successful SETCONFIG call also sets "DPMS" to on, and
999  * 	never read back the value of "DPMS" because it can be incorrect.
1000  * PATH:
1001  * 	Connector path property to identify how this sink is physically
1002  * 	connected. Used by DP MST. This should be set by calling
1003  * 	drm_connector_set_path_property(), in the case of DP MST with the
1004  * 	path property the MST manager created. Userspace cannot change this
1005  * 	property.
1006  * TILE:
1007  * 	Connector tile group property to indicate how a set of DRM connector
1008  * 	compose together into one logical screen. This is used by both high-res
1009  * 	external screens (often only using a single cable, but exposing multiple
1010  * 	DP MST sinks), or high-res integrated panels (like dual-link DSI) which
1011  * 	are not gen-locked. Note that for tiled panels which are genlocked, like
1012  * 	dual-link LVDS or dual-link DSI, the driver should try to not expose the
1013  * 	tiling and virtualise both &drm_crtc and &drm_plane if needed. Drivers
1014  * 	should update this value using drm_connector_set_tile_property().
1015  * 	Userspace cannot change this property.
1016  * link-status:
1017  *      Connector link-status property to indicate the status of link. The
1018  *      default value of link-status is "GOOD". If something fails during or
1019  *      after modeset, the kernel driver may set this to "BAD" and issue a
1020  *      hotplug uevent. Drivers should update this value using
1021  *      drm_connector_set_link_status_property().
1022  *
1023  *      When user-space receives the hotplug uevent and detects a "BAD"
1024  *      link-status, the sink doesn't receive pixels anymore (e.g. the screen
1025  *      becomes completely black). The list of available modes may have
1026  *      changed. User-space is expected to pick a new mode if the current one
1027  *      has disappeared and perform a new modeset with link-status set to
1028  *      "GOOD" to re-enable the connector.
1029  *
1030  *      If multiple connectors share the same CRTC and one of them gets a "BAD"
1031  *      link-status, the other are unaffected (ie. the sinks still continue to
1032  *      receive pixels).
1033  *
1034  *      When user-space performs an atomic commit on a connector with a "BAD"
1035  *      link-status without resetting the property to "GOOD", the sink may
1036  *      still not receive pixels. When user-space performs an atomic commit
1037  *      which resets the link-status property to "GOOD" without the
1038  *      ALLOW_MODESET flag set, it might fail because a modeset is required.
1039  *
1040  *      User-space can only change link-status to "GOOD", changing it to "BAD"
1041  *      is a no-op.
1042  *
1043  *      For backwards compatibility with non-atomic userspace the kernel
1044  *      tries to automatically set the link-status back to "GOOD" in the
1045  *      SETCRTC IOCTL. This might fail if the mode is no longer valid, similar
1046  *      to how it might fail if a different screen has been connected in the
1047  *      interim.
1048  * non_desktop:
1049  * 	Indicates the output should be ignored for purposes of displaying a
1050  * 	standard desktop environment or console. This is most likely because
1051  * 	the output device is not rectilinear.
1052  * Content Protection:
1053  *	This property is used by userspace to request the kernel protect future
1054  *	content communicated over the link. When requested, kernel will apply
1055  *	the appropriate means of protection (most often HDCP), and use the
1056  *	property to tell userspace the protection is active.
1057  *
1058  *	Drivers can set this up by calling
1059  *	drm_connector_attach_content_protection_property() on initialization.
1060  *
1061  *	The value of this property can be one of the following:
1062  *
1063  *	DRM_MODE_CONTENT_PROTECTION_UNDESIRED = 0
1064  *		The link is not protected, content is transmitted in the clear.
1065  *	DRM_MODE_CONTENT_PROTECTION_DESIRED = 1
1066  *		Userspace has requested content protection, but the link is not
1067  *		currently protected. When in this state, kernel should enable
1068  *		Content Protection as soon as possible.
1069  *	DRM_MODE_CONTENT_PROTECTION_ENABLED = 2
1070  *		Userspace has requested content protection, and the link is
1071  *		protected. Only the driver can set the property to this value.
1072  *		If userspace attempts to set to ENABLED, kernel will return
1073  *		-EINVAL.
1074  *
1075  *	A few guidelines:
1076  *
1077  *	- DESIRED state should be preserved until userspace de-asserts it by
1078  *	  setting the property to UNDESIRED. This means ENABLED should only
1079  *	  transition to UNDESIRED when the user explicitly requests it.
1080  *	- If the state is DESIRED, kernel should attempt to re-authenticate the
1081  *	  link whenever possible. This includes across disable/enable, dpms,
1082  *	  hotplug, downstream device changes, link status failures, etc..
1083  *	- Kernel sends uevent with the connector id and property id through
1084  *	  @drm_hdcp_update_content_protection, upon below kernel triggered
1085  *	  scenarios:
1086  *
1087  *		- DESIRED -> ENABLED (authentication success)
1088  *		- ENABLED -> DESIRED (termination of authentication)
1089  *	- Please note no uevents for userspace triggered property state changes,
1090  *	  which can't fail such as
1091  *
1092  *		- DESIRED/ENABLED -> UNDESIRED
1093  *		- UNDESIRED -> DESIRED
1094  *	- Userspace is responsible for polling the property or listen to uevents
1095  *	  to determine when the value transitions from ENABLED to DESIRED.
1096  *	  This signifies the link is no longer protected and userspace should
1097  *	  take appropriate action (whatever that might be).
1098  *
1099  * HDCP Content Type:
1100  *	This Enum property is used by the userspace to declare the content type
1101  *	of the display stream, to kernel. Here display stream stands for any
1102  *	display content that userspace intended to display through HDCP
1103  *	encryption.
1104  *
1105  *	Content Type of a stream is decided by the owner of the stream, as
1106  *	"HDCP Type0" or "HDCP Type1".
1107  *
1108  *	The value of the property can be one of the below:
1109  *	  - "HDCP Type0": DRM_MODE_HDCP_CONTENT_TYPE0 = 0
1110  *	  - "HDCP Type1": DRM_MODE_HDCP_CONTENT_TYPE1 = 1
1111  *
1112  *	When kernel starts the HDCP authentication (see "Content Protection"
1113  *	for details), it uses the content type in "HDCP Content Type"
1114  *	for performing the HDCP authentication with the display sink.
1115  *
1116  *	Please note in HDCP spec versions, a link can be authenticated with
1117  *	HDCP 2.2 for Content Type 0/Content Type 1. Where as a link can be
1118  *	authenticated with HDCP1.4 only for Content Type 0(though it is implicit
1119  *	in nature. As there is no reference for Content Type in HDCP1.4).
1120  *
1121  *	HDCP2.2 authentication protocol itself takes the "Content Type" as a
1122  *	parameter, which is a input for the DP HDCP2.2 encryption algo.
1123  *
1124  *	In case of Type 0 content protection request, kernel driver can choose
1125  *	either of HDCP spec versions 1.4 and 2.2. When HDCP2.2 is used for
1126  *	"HDCP Type 0", a HDCP 2.2 capable repeater in the downstream can send
1127  *	that content to a HDCP 1.4 authenticated HDCP sink (Type0 link).
1128  *	But if the content is classified as "HDCP Type 1", above mentioned
1129  *	HDCP 2.2 repeater wont send the content to the HDCP sink as it can't
1130  *	authenticate the HDCP1.4 capable sink for "HDCP Type 1".
1131  *
1132  *	Please note userspace can be ignorant of the HDCP versions used by the
1133  *	kernel driver to achieve the "HDCP Content Type".
1134  *
1135  *	At current scenario, classifying a content as Type 1 ensures that the
1136  *	content will be displayed only through the HDCP2.2 encrypted link.
1137  *
1138  *	Note that the HDCP Content Type property is introduced at HDCP 2.2, and
1139  *	defaults to type 0. It is only exposed by drivers supporting HDCP 2.2
1140  *	(hence supporting Type 0 and Type 1). Based on how next versions of
1141  *	HDCP specs are defined content Type could be used for higher versions
1142  *	too.
1143  *
1144  *	If content type is changed when "Content Protection" is not UNDESIRED,
1145  *	then kernel will disable the HDCP and re-enable with new type in the
1146  *	same atomic commit. And when "Content Protection" is ENABLED, it means
1147  *	that link is HDCP authenticated and encrypted, for the transmission of
1148  *	the Type of stream mentioned at "HDCP Content Type".
1149  *
1150  * HDR_OUTPUT_METADATA:
1151  *	Connector property to enable userspace to send HDR Metadata to
1152  *	driver. This metadata is based on the composition and blending
1153  *	policies decided by user, taking into account the hardware and
1154  *	sink capabilities. The driver gets this metadata and creates a
1155  *	Dynamic Range and Mastering Infoframe (DRM) in case of HDMI,
1156  *	SDP packet (Non-audio INFOFRAME SDP v1.3) for DP. This is then
1157  *	sent to sink. This notifies the sink of the upcoming frame's Color
1158  *	Encoding and Luminance parameters.
1159  *
1160  *	Userspace first need to detect the HDR capabilities of sink by
1161  *	reading and parsing the EDID. Details of HDR metadata for HDMI
1162  *	are added in CTA 861.G spec. For DP , its defined in VESA DP
1163  *	Standard v1.4. It needs to then get the metadata information
1164  *	of the video/game/app content which are encoded in HDR (basically
1165  *	using HDR transfer functions). With this information it needs to
1166  *	decide on a blending policy and compose the relevant
1167  *	layers/overlays into a common format. Once this blending is done,
1168  *	userspace will be aware of the metadata of the composed frame to
1169  *	be send to sink. It then uses this property to communicate this
1170  *	metadata to driver which then make a Infoframe packet and sends
1171  *	to sink based on the type of encoder connected.
1172  *
1173  *	Userspace will be responsible to do Tone mapping operation in case:
1174  *		- Some layers are HDR and others are SDR
1175  *		- HDR layers luminance is not same as sink
1176  *
1177  *	It will even need to do colorspace conversion and get all layers
1178  *	to one common colorspace for blending. It can use either GL, Media
1179  *	or display engine to get this done based on the capabilities of the
1180  *	associated hardware.
1181  *
1182  *	Driver expects metadata to be put in &struct hdr_output_metadata
1183  *	structure from userspace. This is received as blob and stored in
1184  *	&drm_connector_state.hdr_output_metadata. It parses EDID and saves the
1185  *	sink metadata in &struct hdr_sink_metadata, as
1186  *	&drm_connector.hdr_sink_metadata.  Driver uses
1187  *	drm_hdmi_infoframe_set_hdr_metadata() helper to set the HDR metadata,
1188  *	hdmi_drm_infoframe_pack() to pack the infoframe as per spec, in case of
1189  *	HDMI encoder.
1190  *
1191  * max bpc:
1192  *	This range property is used by userspace to limit the bit depth. When
1193  *	used the driver would limit the bpc in accordance with the valid range
1194  *	supported by the hardware and sink. Drivers to use the function
1195  *	drm_connector_attach_max_bpc_property() to create and attach the
1196  *	property to the connector during initialization.
1197  *
1198  * Connectors also have one standardized atomic property:
1199  *
1200  * CRTC_ID:
1201  * 	Mode object ID of the &drm_crtc this connector should be connected to.
1202  *
1203  * Connectors for LCD panels may also have one standardized property:
1204  *
1205  * panel orientation:
1206  *	On some devices the LCD panel is mounted in the casing in such a way
1207  *	that the up/top side of the panel does not match with the top side of
1208  *	the device. Userspace can use this property to check for this.
1209  *	Note that input coordinates from touchscreens (input devices with
1210  *	INPUT_PROP_DIRECT) will still map 1:1 to the actual LCD panel
1211  *	coordinates, so if userspace rotates the picture to adjust for
1212  *	the orientation it must also apply the same transformation to the
1213  *	touchscreen input coordinates. This property is initialized by calling
1214  *	drm_connector_set_panel_orientation() or
1215  *	drm_connector_set_panel_orientation_with_quirk()
1216  *
1217  * scaling mode:
1218  *	This property defines how a non-native mode is upscaled to the native
1219  *	mode of an LCD panel:
1220  *
1221  *	None:
1222  *		No upscaling happens, scaling is left to the panel. Not all
1223  *		drivers expose this mode.
1224  *	Full:
1225  *		The output is upscaled to the full resolution of the panel,
1226  *		ignoring the aspect ratio.
1227  *	Center:
1228  *		No upscaling happens, the output is centered within the native
1229  *		resolution the panel.
1230  *	Full aspect:
1231  *		The output is upscaled to maximize either the width or height
1232  *		while retaining the aspect ratio.
1233  *
1234  *	This property should be set up by calling
1235  *	drm_connector_attach_scaling_mode_property(). Note that drivers
1236  *	can also expose this property to external outputs, in which case they
1237  *	must support "None", which should be the default (since external screens
1238  *	have a built-in scaler).
1239  *
1240  * subconnector:
1241  *	This property is used by DVI-I, TVout and DisplayPort to indicate different
1242  *	connector subtypes. Enum values more or less match with those from main
1243  *	connector types.
1244  *	For DVI-I and TVout there is also a matching property "select subconnector"
1245  *	allowing to switch between signal types.
1246  *	DP subconnector corresponds to a downstream port.
1247  */
1248 
1249 int drm_connector_create_standard_properties(struct drm_device *dev)
1250 {
1251 	struct drm_property *prop;
1252 
1253 	prop = drm_property_create(dev, DRM_MODE_PROP_BLOB |
1254 				   DRM_MODE_PROP_IMMUTABLE,
1255 				   "EDID", 0);
1256 	if (!prop)
1257 		return -ENOMEM;
1258 	dev->mode_config.edid_property = prop;
1259 
1260 	prop = drm_property_create_enum(dev, 0,
1261 				   "DPMS", drm_dpms_enum_list,
1262 				   ARRAY_SIZE(drm_dpms_enum_list));
1263 	if (!prop)
1264 		return -ENOMEM;
1265 	dev->mode_config.dpms_property = prop;
1266 
1267 	prop = drm_property_create(dev,
1268 				   DRM_MODE_PROP_BLOB |
1269 				   DRM_MODE_PROP_IMMUTABLE,
1270 				   "PATH", 0);
1271 	if (!prop)
1272 		return -ENOMEM;
1273 	dev->mode_config.path_property = prop;
1274 
1275 	prop = drm_property_create(dev,
1276 				   DRM_MODE_PROP_BLOB |
1277 				   DRM_MODE_PROP_IMMUTABLE,
1278 				   "TILE", 0);
1279 	if (!prop)
1280 		return -ENOMEM;
1281 	dev->mode_config.tile_property = prop;
1282 
1283 	prop = drm_property_create_enum(dev, 0, "link-status",
1284 					drm_link_status_enum_list,
1285 					ARRAY_SIZE(drm_link_status_enum_list));
1286 	if (!prop)
1287 		return -ENOMEM;
1288 	dev->mode_config.link_status_property = prop;
1289 
1290 	prop = drm_property_create_bool(dev, DRM_MODE_PROP_IMMUTABLE, "non-desktop");
1291 	if (!prop)
1292 		return -ENOMEM;
1293 	dev->mode_config.non_desktop_property = prop;
1294 
1295 	prop = drm_property_create(dev, DRM_MODE_PROP_BLOB,
1296 				   "HDR_OUTPUT_METADATA", 0);
1297 	if (!prop)
1298 		return -ENOMEM;
1299 	dev->mode_config.hdr_output_metadata_property = prop;
1300 
1301 	return 0;
1302 }
1303 
1304 /**
1305  * drm_mode_create_dvi_i_properties - create DVI-I specific connector properties
1306  * @dev: DRM device
1307  *
1308  * Called by a driver the first time a DVI-I connector is made.
1309  */
1310 int drm_mode_create_dvi_i_properties(struct drm_device *dev)
1311 {
1312 	struct drm_property *dvi_i_selector;
1313 	struct drm_property *dvi_i_subconnector;
1314 
1315 	if (dev->mode_config.dvi_i_select_subconnector_property)
1316 		return 0;
1317 
1318 	dvi_i_selector =
1319 		drm_property_create_enum(dev, 0,
1320 				    "select subconnector",
1321 				    drm_dvi_i_select_enum_list,
1322 				    ARRAY_SIZE(drm_dvi_i_select_enum_list));
1323 	dev->mode_config.dvi_i_select_subconnector_property = dvi_i_selector;
1324 
1325 	dvi_i_subconnector = drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
1326 				    "subconnector",
1327 				    drm_dvi_i_subconnector_enum_list,
1328 				    ARRAY_SIZE(drm_dvi_i_subconnector_enum_list));
1329 	dev->mode_config.dvi_i_subconnector_property = dvi_i_subconnector;
1330 
1331 	return 0;
1332 }
1333 EXPORT_SYMBOL(drm_mode_create_dvi_i_properties);
1334 
1335 /**
1336  * drm_connector_attach_dp_subconnector_property - create subconnector property for DP
1337  * @connector: drm_connector to attach property
1338  *
1339  * Called by a driver when DP connector is created.
1340  */
1341 void drm_connector_attach_dp_subconnector_property(struct drm_connector *connector)
1342 {
1343 	struct drm_mode_config *mode_config = &connector->dev->mode_config;
1344 
1345 	if (!mode_config->dp_subconnector_property)
1346 		mode_config->dp_subconnector_property =
1347 			drm_property_create_enum(connector->dev,
1348 				DRM_MODE_PROP_IMMUTABLE,
1349 				"subconnector",
1350 				drm_dp_subconnector_enum_list,
1351 				ARRAY_SIZE(drm_dp_subconnector_enum_list));
1352 
1353 	drm_object_attach_property(&connector->base,
1354 				   mode_config->dp_subconnector_property,
1355 				   DRM_MODE_SUBCONNECTOR_Unknown);
1356 }
1357 EXPORT_SYMBOL(drm_connector_attach_dp_subconnector_property);
1358 
1359 /**
1360  * DOC: HDMI connector properties
1361  *
1362  * content type (HDMI specific):
1363  *	Indicates content type setting to be used in HDMI infoframes to indicate
1364  *	content type for the external device, so that it adjusts its display
1365  *	settings accordingly.
1366  *
1367  *	The value of this property can be one of the following:
1368  *
1369  *	No Data:
1370  *		Content type is unknown
1371  *	Graphics:
1372  *		Content type is graphics
1373  *	Photo:
1374  *		Content type is photo
1375  *	Cinema:
1376  *		Content type is cinema
1377  *	Game:
1378  *		Content type is game
1379  *
1380  *	Drivers can set up this property by calling
1381  *	drm_connector_attach_content_type_property(). Decoding to
1382  *	infoframe values is done through drm_hdmi_avi_infoframe_content_type().
1383  */
1384 
1385 /**
1386  * drm_connector_attach_content_type_property - attach content-type property
1387  * @connector: connector to attach content type property on.
1388  *
1389  * Called by a driver the first time a HDMI connector is made.
1390  */
1391 int drm_connector_attach_content_type_property(struct drm_connector *connector)
1392 {
1393 	if (!drm_mode_create_content_type_property(connector->dev))
1394 		drm_object_attach_property(&connector->base,
1395 					   connector->dev->mode_config.content_type_property,
1396 					   DRM_MODE_CONTENT_TYPE_NO_DATA);
1397 	return 0;
1398 }
1399 EXPORT_SYMBOL(drm_connector_attach_content_type_property);
1400 
1401 
1402 /**
1403  * drm_hdmi_avi_infoframe_content_type() - fill the HDMI AVI infoframe
1404  *                                         content type information, based
1405  *                                         on correspondent DRM property.
1406  * @frame: HDMI AVI infoframe
1407  * @conn_state: DRM display connector state
1408  *
1409  */
1410 void drm_hdmi_avi_infoframe_content_type(struct hdmi_avi_infoframe *frame,
1411 					 const struct drm_connector_state *conn_state)
1412 {
1413 	switch (conn_state->content_type) {
1414 	case DRM_MODE_CONTENT_TYPE_GRAPHICS:
1415 		frame->content_type = HDMI_CONTENT_TYPE_GRAPHICS;
1416 		break;
1417 	case DRM_MODE_CONTENT_TYPE_CINEMA:
1418 		frame->content_type = HDMI_CONTENT_TYPE_CINEMA;
1419 		break;
1420 	case DRM_MODE_CONTENT_TYPE_GAME:
1421 		frame->content_type = HDMI_CONTENT_TYPE_GAME;
1422 		break;
1423 	case DRM_MODE_CONTENT_TYPE_PHOTO:
1424 		frame->content_type = HDMI_CONTENT_TYPE_PHOTO;
1425 		break;
1426 	default:
1427 		/* Graphics is the default(0) */
1428 		frame->content_type = HDMI_CONTENT_TYPE_GRAPHICS;
1429 	}
1430 
1431 	frame->itc = conn_state->content_type != DRM_MODE_CONTENT_TYPE_NO_DATA;
1432 }
1433 EXPORT_SYMBOL(drm_hdmi_avi_infoframe_content_type);
1434 
1435 /**
1436  * drm_connector_attach_tv_margin_properties - attach TV connector margin
1437  * 	properties
1438  * @connector: DRM connector
1439  *
1440  * Called by a driver when it needs to attach TV margin props to a connector.
1441  * Typically used on SDTV and HDMI connectors.
1442  */
1443 void drm_connector_attach_tv_margin_properties(struct drm_connector *connector)
1444 {
1445 	struct drm_device *dev = connector->dev;
1446 
1447 	drm_object_attach_property(&connector->base,
1448 				   dev->mode_config.tv_left_margin_property,
1449 				   0);
1450 	drm_object_attach_property(&connector->base,
1451 				   dev->mode_config.tv_right_margin_property,
1452 				   0);
1453 	drm_object_attach_property(&connector->base,
1454 				   dev->mode_config.tv_top_margin_property,
1455 				   0);
1456 	drm_object_attach_property(&connector->base,
1457 				   dev->mode_config.tv_bottom_margin_property,
1458 				   0);
1459 }
1460 EXPORT_SYMBOL(drm_connector_attach_tv_margin_properties);
1461 
1462 /**
1463  * drm_mode_create_tv_margin_properties - create TV connector margin properties
1464  * @dev: DRM device
1465  *
1466  * Called by a driver's HDMI connector initialization routine, this function
1467  * creates the TV margin properties for a given device. No need to call this
1468  * function for an SDTV connector, it's already called from
1469  * drm_mode_create_tv_properties().
1470  */
1471 int drm_mode_create_tv_margin_properties(struct drm_device *dev)
1472 {
1473 	if (dev->mode_config.tv_left_margin_property)
1474 		return 0;
1475 
1476 	dev->mode_config.tv_left_margin_property =
1477 		drm_property_create_range(dev, 0, "left margin", 0, 100);
1478 	if (!dev->mode_config.tv_left_margin_property)
1479 		return -ENOMEM;
1480 
1481 	dev->mode_config.tv_right_margin_property =
1482 		drm_property_create_range(dev, 0, "right margin", 0, 100);
1483 	if (!dev->mode_config.tv_right_margin_property)
1484 		return -ENOMEM;
1485 
1486 	dev->mode_config.tv_top_margin_property =
1487 		drm_property_create_range(dev, 0, "top margin", 0, 100);
1488 	if (!dev->mode_config.tv_top_margin_property)
1489 		return -ENOMEM;
1490 
1491 	dev->mode_config.tv_bottom_margin_property =
1492 		drm_property_create_range(dev, 0, "bottom margin", 0, 100);
1493 	if (!dev->mode_config.tv_bottom_margin_property)
1494 		return -ENOMEM;
1495 
1496 	return 0;
1497 }
1498 EXPORT_SYMBOL(drm_mode_create_tv_margin_properties);
1499 
1500 /**
1501  * drm_mode_create_tv_properties - create TV specific connector properties
1502  * @dev: DRM device
1503  * @num_modes: number of different TV formats (modes) supported
1504  * @modes: array of pointers to strings containing name of each format
1505  *
1506  * Called by a driver's TV initialization routine, this function creates
1507  * the TV specific connector properties for a given device.  Caller is
1508  * responsible for allocating a list of format names and passing them to
1509  * this routine.
1510  */
1511 int drm_mode_create_tv_properties(struct drm_device *dev,
1512 				  unsigned int num_modes,
1513 				  const char * const modes[])
1514 {
1515 	struct drm_property *tv_selector;
1516 	struct drm_property *tv_subconnector;
1517 	unsigned int i;
1518 
1519 	if (dev->mode_config.tv_select_subconnector_property)
1520 		return 0;
1521 
1522 	/*
1523 	 * Basic connector properties
1524 	 */
1525 	tv_selector = drm_property_create_enum(dev, 0,
1526 					  "select subconnector",
1527 					  drm_tv_select_enum_list,
1528 					  ARRAY_SIZE(drm_tv_select_enum_list));
1529 	if (!tv_selector)
1530 		goto nomem;
1531 
1532 	dev->mode_config.tv_select_subconnector_property = tv_selector;
1533 
1534 	tv_subconnector =
1535 		drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
1536 				    "subconnector",
1537 				    drm_tv_subconnector_enum_list,
1538 				    ARRAY_SIZE(drm_tv_subconnector_enum_list));
1539 	if (!tv_subconnector)
1540 		goto nomem;
1541 	dev->mode_config.tv_subconnector_property = tv_subconnector;
1542 
1543 	/*
1544 	 * Other, TV specific properties: margins & TV modes.
1545 	 */
1546 	if (drm_mode_create_tv_margin_properties(dev))
1547 		goto nomem;
1548 
1549 	dev->mode_config.tv_mode_property =
1550 		drm_property_create(dev, DRM_MODE_PROP_ENUM,
1551 				    "mode", num_modes);
1552 	if (!dev->mode_config.tv_mode_property)
1553 		goto nomem;
1554 
1555 	for (i = 0; i < num_modes; i++)
1556 		drm_property_add_enum(dev->mode_config.tv_mode_property,
1557 				      i, modes[i]);
1558 
1559 	dev->mode_config.tv_brightness_property =
1560 		drm_property_create_range(dev, 0, "brightness", 0, 100);
1561 	if (!dev->mode_config.tv_brightness_property)
1562 		goto nomem;
1563 
1564 	dev->mode_config.tv_contrast_property =
1565 		drm_property_create_range(dev, 0, "contrast", 0, 100);
1566 	if (!dev->mode_config.tv_contrast_property)
1567 		goto nomem;
1568 
1569 	dev->mode_config.tv_flicker_reduction_property =
1570 		drm_property_create_range(dev, 0, "flicker reduction", 0, 100);
1571 	if (!dev->mode_config.tv_flicker_reduction_property)
1572 		goto nomem;
1573 
1574 	dev->mode_config.tv_overscan_property =
1575 		drm_property_create_range(dev, 0, "overscan", 0, 100);
1576 	if (!dev->mode_config.tv_overscan_property)
1577 		goto nomem;
1578 
1579 	dev->mode_config.tv_saturation_property =
1580 		drm_property_create_range(dev, 0, "saturation", 0, 100);
1581 	if (!dev->mode_config.tv_saturation_property)
1582 		goto nomem;
1583 
1584 	dev->mode_config.tv_hue_property =
1585 		drm_property_create_range(dev, 0, "hue", 0, 100);
1586 	if (!dev->mode_config.tv_hue_property)
1587 		goto nomem;
1588 
1589 	return 0;
1590 nomem:
1591 	return -ENOMEM;
1592 }
1593 EXPORT_SYMBOL(drm_mode_create_tv_properties);
1594 
1595 /**
1596  * drm_mode_create_scaling_mode_property - create scaling mode property
1597  * @dev: DRM device
1598  *
1599  * Called by a driver the first time it's needed, must be attached to desired
1600  * connectors.
1601  *
1602  * Atomic drivers should use drm_connector_attach_scaling_mode_property()
1603  * instead to correctly assign &drm_connector_state.picture_aspect_ratio
1604  * in the atomic state.
1605  */
1606 int drm_mode_create_scaling_mode_property(struct drm_device *dev)
1607 {
1608 	struct drm_property *scaling_mode;
1609 
1610 	if (dev->mode_config.scaling_mode_property)
1611 		return 0;
1612 
1613 	scaling_mode =
1614 		drm_property_create_enum(dev, 0, "scaling mode",
1615 				drm_scaling_mode_enum_list,
1616 				    ARRAY_SIZE(drm_scaling_mode_enum_list));
1617 
1618 	dev->mode_config.scaling_mode_property = scaling_mode;
1619 
1620 	return 0;
1621 }
1622 EXPORT_SYMBOL(drm_mode_create_scaling_mode_property);
1623 
1624 /**
1625  * DOC: Variable refresh properties
1626  *
1627  * Variable refresh rate capable displays can dynamically adjust their
1628  * refresh rate by extending the duration of their vertical front porch
1629  * until page flip or timeout occurs. This can reduce or remove stuttering
1630  * and latency in scenarios where the page flip does not align with the
1631  * vblank interval.
1632  *
1633  * An example scenario would be an application flipping at a constant rate
1634  * of 48Hz on a 60Hz display. The page flip will frequently miss the vblank
1635  * interval and the same contents will be displayed twice. This can be
1636  * observed as stuttering for content with motion.
1637  *
1638  * If variable refresh rate was active on a display that supported a
1639  * variable refresh range from 35Hz to 60Hz no stuttering would be observable
1640  * for the example scenario. The minimum supported variable refresh rate of
1641  * 35Hz is below the page flip frequency and the vertical front porch can
1642  * be extended until the page flip occurs. The vblank interval will be
1643  * directly aligned to the page flip rate.
1644  *
1645  * Not all userspace content is suitable for use with variable refresh rate.
1646  * Large and frequent changes in vertical front porch duration may worsen
1647  * perceived stuttering for input sensitive applications.
1648  *
1649  * Panel brightness will also vary with vertical front porch duration. Some
1650  * panels may have noticeable differences in brightness between the minimum
1651  * vertical front porch duration and the maximum vertical front porch duration.
1652  * Large and frequent changes in vertical front porch duration may produce
1653  * observable flickering for such panels.
1654  *
1655  * Userspace control for variable refresh rate is supported via properties
1656  * on the &drm_connector and &drm_crtc objects.
1657  *
1658  * "vrr_capable":
1659  *	Optional &drm_connector boolean property that drivers should attach
1660  *	with drm_connector_attach_vrr_capable_property() on connectors that
1661  *	could support variable refresh rates. Drivers should update the
1662  *	property value by calling drm_connector_set_vrr_capable_property().
1663  *
1664  *	Absence of the property should indicate absence of support.
1665  *
1666  * "VRR_ENABLED":
1667  *	Default &drm_crtc boolean property that notifies the driver that the
1668  *	content on the CRTC is suitable for variable refresh rate presentation.
1669  *	The driver will take this property as a hint to enable variable
1670  *	refresh rate support if the receiver supports it, ie. if the
1671  *	"vrr_capable" property is true on the &drm_connector object. The
1672  *	vertical front porch duration will be extended until page-flip or
1673  *	timeout when enabled.
1674  *
1675  *	The minimum vertical front porch duration is defined as the vertical
1676  *	front porch duration for the current mode.
1677  *
1678  *	The maximum vertical front porch duration is greater than or equal to
1679  *	the minimum vertical front porch duration. The duration is derived
1680  *	from the minimum supported variable refresh rate for the connector.
1681  *
1682  *	The driver may place further restrictions within these minimum
1683  *	and maximum bounds.
1684  */
1685 
1686 /**
1687  * drm_connector_attach_vrr_capable_property - creates the
1688  * vrr_capable property
1689  * @connector: connector to create the vrr_capable property on.
1690  *
1691  * This is used by atomic drivers to add support for querying
1692  * variable refresh rate capability for a connector.
1693  *
1694  * Returns:
1695  * Zero on success, negative errno on failure.
1696  */
1697 int drm_connector_attach_vrr_capable_property(
1698 	struct drm_connector *connector)
1699 {
1700 	struct drm_device *dev = connector->dev;
1701 	struct drm_property *prop;
1702 
1703 	if (!connector->vrr_capable_property) {
1704 		prop = drm_property_create_bool(dev, DRM_MODE_PROP_IMMUTABLE,
1705 			"vrr_capable");
1706 		if (!prop)
1707 			return -ENOMEM;
1708 
1709 		connector->vrr_capable_property = prop;
1710 		drm_object_attach_property(&connector->base, prop, 0);
1711 	}
1712 
1713 	return 0;
1714 }
1715 EXPORT_SYMBOL(drm_connector_attach_vrr_capable_property);
1716 
1717 /**
1718  * drm_connector_attach_scaling_mode_property - attach atomic scaling mode property
1719  * @connector: connector to attach scaling mode property on.
1720  * @scaling_mode_mask: or'ed mask of BIT(%DRM_MODE_SCALE_\*).
1721  *
1722  * This is used to add support for scaling mode to atomic drivers.
1723  * The scaling mode will be set to &drm_connector_state.picture_aspect_ratio
1724  * and can be used from &drm_connector_helper_funcs->atomic_check for validation.
1725  *
1726  * This is the atomic version of drm_mode_create_scaling_mode_property().
1727  *
1728  * Returns:
1729  * Zero on success, negative errno on failure.
1730  */
1731 int drm_connector_attach_scaling_mode_property(struct drm_connector *connector,
1732 					       u32 scaling_mode_mask)
1733 {
1734 	struct drm_device *dev = connector->dev;
1735 	struct drm_property *scaling_mode_property;
1736 	int i;
1737 	const unsigned valid_scaling_mode_mask =
1738 		(1U << ARRAY_SIZE(drm_scaling_mode_enum_list)) - 1;
1739 
1740 	if (WARN_ON(hweight32(scaling_mode_mask) < 2 ||
1741 		    scaling_mode_mask & ~valid_scaling_mode_mask))
1742 		return -EINVAL;
1743 
1744 	scaling_mode_property =
1745 		drm_property_create(dev, DRM_MODE_PROP_ENUM, "scaling mode",
1746 				    hweight32(scaling_mode_mask));
1747 
1748 	if (!scaling_mode_property)
1749 		return -ENOMEM;
1750 
1751 	for (i = 0; i < ARRAY_SIZE(drm_scaling_mode_enum_list); i++) {
1752 		int ret;
1753 
1754 		if (!(BIT(i) & scaling_mode_mask))
1755 			continue;
1756 
1757 		ret = drm_property_add_enum(scaling_mode_property,
1758 					    drm_scaling_mode_enum_list[i].type,
1759 					    drm_scaling_mode_enum_list[i].name);
1760 
1761 		if (ret) {
1762 			drm_property_destroy(dev, scaling_mode_property);
1763 
1764 			return ret;
1765 		}
1766 	}
1767 
1768 	drm_object_attach_property(&connector->base,
1769 				   scaling_mode_property, 0);
1770 
1771 	connector->scaling_mode_property = scaling_mode_property;
1772 
1773 	return 0;
1774 }
1775 EXPORT_SYMBOL(drm_connector_attach_scaling_mode_property);
1776 
1777 /**
1778  * drm_mode_create_aspect_ratio_property - create aspect ratio property
1779  * @dev: DRM device
1780  *
1781  * Called by a driver the first time it's needed, must be attached to desired
1782  * connectors.
1783  *
1784  * Returns:
1785  * Zero on success, negative errno on failure.
1786  */
1787 int drm_mode_create_aspect_ratio_property(struct drm_device *dev)
1788 {
1789 	if (dev->mode_config.aspect_ratio_property)
1790 		return 0;
1791 
1792 	dev->mode_config.aspect_ratio_property =
1793 		drm_property_create_enum(dev, 0, "aspect ratio",
1794 				drm_aspect_ratio_enum_list,
1795 				ARRAY_SIZE(drm_aspect_ratio_enum_list));
1796 
1797 	if (dev->mode_config.aspect_ratio_property == NULL)
1798 		return -ENOMEM;
1799 
1800 	return 0;
1801 }
1802 EXPORT_SYMBOL(drm_mode_create_aspect_ratio_property);
1803 
1804 /**
1805  * DOC: standard connector properties
1806  *
1807  * Colorspace:
1808  *     This property helps select a suitable colorspace based on the sink
1809  *     capability. Modern sink devices support wider gamut like BT2020.
1810  *     This helps switch to BT2020 mode if the BT2020 encoded video stream
1811  *     is being played by the user, same for any other colorspace. Thereby
1812  *     giving a good visual experience to users.
1813  *
1814  *     The expectation from userspace is that it should parse the EDID
1815  *     and get supported colorspaces. Use this property and switch to the
1816  *     one supported. Sink supported colorspaces should be retrieved by
1817  *     userspace from EDID and driver will not explicitly expose them.
1818  *
1819  *     Basically the expectation from userspace is:
1820  *      - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink
1821  *        colorspace
1822  *      - Set this new property to let the sink know what it
1823  *        converted the CRTC output to.
1824  *      - This property is just to inform sink what colorspace
1825  *        source is trying to drive.
1826  *
1827  * Because between HDMI and DP have different colorspaces,
1828  * drm_mode_create_hdmi_colorspace_property() is used for HDMI connector and
1829  * drm_mode_create_dp_colorspace_property() is used for DP connector.
1830  */
1831 
1832 /**
1833  * drm_mode_create_hdmi_colorspace_property - create hdmi colorspace property
1834  * @connector: connector to create the Colorspace property on.
1835  *
1836  * Called by a driver the first time it's needed, must be attached to desired
1837  * HDMI connectors.
1838  *
1839  * Returns:
1840  * Zero on success, negative errno on failure.
1841  */
1842 int drm_mode_create_hdmi_colorspace_property(struct drm_connector *connector)
1843 {
1844 	struct drm_device *dev = connector->dev;
1845 
1846 	if (connector->colorspace_property)
1847 		return 0;
1848 
1849 	connector->colorspace_property =
1850 		drm_property_create_enum(dev, DRM_MODE_PROP_ENUM, "Colorspace",
1851 					 hdmi_colorspaces,
1852 					 ARRAY_SIZE(hdmi_colorspaces));
1853 
1854 	if (!connector->colorspace_property)
1855 		return -ENOMEM;
1856 
1857 	return 0;
1858 }
1859 EXPORT_SYMBOL(drm_mode_create_hdmi_colorspace_property);
1860 
1861 /**
1862  * drm_mode_create_dp_colorspace_property - create dp colorspace property
1863  * @connector: connector to create the Colorspace property on.
1864  *
1865  * Called by a driver the first time it's needed, must be attached to desired
1866  * DP connectors.
1867  *
1868  * Returns:
1869  * Zero on success, negative errno on failure.
1870  */
1871 int drm_mode_create_dp_colorspace_property(struct drm_connector *connector)
1872 {
1873 	struct drm_device *dev = connector->dev;
1874 
1875 	if (connector->colorspace_property)
1876 		return 0;
1877 
1878 	connector->colorspace_property =
1879 		drm_property_create_enum(dev, DRM_MODE_PROP_ENUM, "Colorspace",
1880 					 dp_colorspaces,
1881 					 ARRAY_SIZE(dp_colorspaces));
1882 
1883 	if (!connector->colorspace_property)
1884 		return -ENOMEM;
1885 
1886 	return 0;
1887 }
1888 EXPORT_SYMBOL(drm_mode_create_dp_colorspace_property);
1889 
1890 /**
1891  * drm_mode_create_content_type_property - create content type property
1892  * @dev: DRM device
1893  *
1894  * Called by a driver the first time it's needed, must be attached to desired
1895  * connectors.
1896  *
1897  * Returns:
1898  * Zero on success, negative errno on failure.
1899  */
1900 int drm_mode_create_content_type_property(struct drm_device *dev)
1901 {
1902 	if (dev->mode_config.content_type_property)
1903 		return 0;
1904 
1905 	dev->mode_config.content_type_property =
1906 		drm_property_create_enum(dev, 0, "content type",
1907 					 drm_content_type_enum_list,
1908 					 ARRAY_SIZE(drm_content_type_enum_list));
1909 
1910 	if (dev->mode_config.content_type_property == NULL)
1911 		return -ENOMEM;
1912 
1913 	return 0;
1914 }
1915 EXPORT_SYMBOL(drm_mode_create_content_type_property);
1916 
1917 /**
1918  * drm_mode_create_suggested_offset_properties - create suggests offset properties
1919  * @dev: DRM device
1920  *
1921  * Create the suggested x/y offset property for connectors.
1922  */
1923 int drm_mode_create_suggested_offset_properties(struct drm_device *dev)
1924 {
1925 	if (dev->mode_config.suggested_x_property && dev->mode_config.suggested_y_property)
1926 		return 0;
1927 
1928 	dev->mode_config.suggested_x_property =
1929 		drm_property_create_range(dev, DRM_MODE_PROP_IMMUTABLE, "suggested X", 0, 0xffffffff);
1930 
1931 	dev->mode_config.suggested_y_property =
1932 		drm_property_create_range(dev, DRM_MODE_PROP_IMMUTABLE, "suggested Y", 0, 0xffffffff);
1933 
1934 	if (dev->mode_config.suggested_x_property == NULL ||
1935 	    dev->mode_config.suggested_y_property == NULL)
1936 		return -ENOMEM;
1937 	return 0;
1938 }
1939 EXPORT_SYMBOL(drm_mode_create_suggested_offset_properties);
1940 
1941 /**
1942  * drm_connector_set_path_property - set tile property on connector
1943  * @connector: connector to set property on.
1944  * @path: path to use for property; must not be NULL.
1945  *
1946  * This creates a property to expose to userspace to specify a
1947  * connector path. This is mainly used for DisplayPort MST where
1948  * connectors have a topology and we want to allow userspace to give
1949  * them more meaningful names.
1950  *
1951  * Returns:
1952  * Zero on success, negative errno on failure.
1953  */
1954 int drm_connector_set_path_property(struct drm_connector *connector,
1955 				    const char *path)
1956 {
1957 	struct drm_device *dev = connector->dev;
1958 	int ret;
1959 
1960 	ret = drm_property_replace_global_blob(dev,
1961 	                                       &connector->path_blob_ptr,
1962 	                                       strlen(path) + 1,
1963 	                                       path,
1964 	                                       &connector->base,
1965 	                                       dev->mode_config.path_property);
1966 	return ret;
1967 }
1968 EXPORT_SYMBOL(drm_connector_set_path_property);
1969 
1970 /**
1971  * drm_connector_set_tile_property - set tile property on connector
1972  * @connector: connector to set property on.
1973  *
1974  * This looks up the tile information for a connector, and creates a
1975  * property for userspace to parse if it exists. The property is of
1976  * the form of 8 integers using ':' as a separator.
1977  * This is used for dual port tiled displays with DisplayPort SST
1978  * or DisplayPort MST connectors.
1979  *
1980  * Returns:
1981  * Zero on success, errno on failure.
1982  */
1983 int drm_connector_set_tile_property(struct drm_connector *connector)
1984 {
1985 	struct drm_device *dev = connector->dev;
1986 	char tile[256];
1987 	int ret;
1988 
1989 	if (!connector->has_tile) {
1990 		ret  = drm_property_replace_global_blob(dev,
1991 		                                        &connector->tile_blob_ptr,
1992 		                                        0,
1993 		                                        NULL,
1994 		                                        &connector->base,
1995 		                                        dev->mode_config.tile_property);
1996 		return ret;
1997 	}
1998 
1999 	snprintf(tile, 256, "%d:%d:%d:%d:%d:%d:%d:%d",
2000 		 connector->tile_group->id, connector->tile_is_single_monitor,
2001 		 connector->num_h_tile, connector->num_v_tile,
2002 		 connector->tile_h_loc, connector->tile_v_loc,
2003 		 connector->tile_h_size, connector->tile_v_size);
2004 
2005 	ret = drm_property_replace_global_blob(dev,
2006 	                                       &connector->tile_blob_ptr,
2007 	                                       strlen(tile) + 1,
2008 	                                       tile,
2009 	                                       &connector->base,
2010 	                                       dev->mode_config.tile_property);
2011 	return ret;
2012 }
2013 EXPORT_SYMBOL(drm_connector_set_tile_property);
2014 
2015 /**
2016  * drm_connector_update_edid_property - update the edid property of a connector
2017  * @connector: drm connector
2018  * @edid: new value of the edid property
2019  *
2020  * This function creates a new blob modeset object and assigns its id to the
2021  * connector's edid property.
2022  * Since we also parse tile information from EDID's displayID block, we also
2023  * set the connector's tile property here. See drm_connector_set_tile_property()
2024  * for more details.
2025  *
2026  * Returns:
2027  * Zero on success, negative errno on failure.
2028  */
2029 int drm_connector_update_edid_property(struct drm_connector *connector,
2030 				       const struct edid *edid)
2031 {
2032 	struct drm_device *dev = connector->dev;
2033 	size_t size = 0;
2034 	int ret;
2035 	const struct edid *old_edid;
2036 
2037 	/* ignore requests to set edid when overridden */
2038 	if (connector->override_edid)
2039 		return 0;
2040 
2041 	if (edid)
2042 		size = EDID_LENGTH * (1 + edid->extensions);
2043 
2044 	/* Set the display info, using edid if available, otherwise
2045 	 * resetting the values to defaults. This duplicates the work
2046 	 * done in drm_add_edid_modes, but that function is not
2047 	 * consistently called before this one in all drivers and the
2048 	 * computation is cheap enough that it seems better to
2049 	 * duplicate it rather than attempt to ensure some arbitrary
2050 	 * ordering of calls.
2051 	 */
2052 	if (edid)
2053 		drm_add_display_info(connector, edid);
2054 	else
2055 		drm_reset_display_info(connector);
2056 
2057 	drm_update_tile_info(connector, edid);
2058 
2059 	if (connector->edid_blob_ptr) {
2060 		old_edid = (const struct edid *)connector->edid_blob_ptr->data;
2061 		if (old_edid) {
2062 			if (!drm_edid_are_equal(edid, old_edid)) {
2063 				DRM_DEBUG_KMS("[CONNECTOR:%d:%s] Edid was changed.\n",
2064 					      connector->base.id, connector->name);
2065 
2066 				connector->epoch_counter += 1;
2067 				DRM_DEBUG_KMS("Updating change counter to %llu\n",
2068 					      connector->epoch_counter);
2069 			}
2070 		}
2071 	}
2072 
2073 	drm_object_property_set_value(&connector->base,
2074 				      dev->mode_config.non_desktop_property,
2075 				      connector->display_info.non_desktop);
2076 
2077 	ret = drm_property_replace_global_blob(dev,
2078 					       &connector->edid_blob_ptr,
2079 	                                       size,
2080 	                                       edid,
2081 	                                       &connector->base,
2082 	                                       dev->mode_config.edid_property);
2083 	if (ret)
2084 		return ret;
2085 	return drm_connector_set_tile_property(connector);
2086 }
2087 EXPORT_SYMBOL(drm_connector_update_edid_property);
2088 
2089 /**
2090  * drm_connector_set_link_status_property - Set link status property of a connector
2091  * @connector: drm connector
2092  * @link_status: new value of link status property (0: Good, 1: Bad)
2093  *
2094  * In usual working scenario, this link status property will always be set to
2095  * "GOOD". If something fails during or after a mode set, the kernel driver
2096  * may set this link status property to "BAD". The caller then needs to send a
2097  * hotplug uevent for userspace to re-check the valid modes through
2098  * GET_CONNECTOR_IOCTL and retry modeset.
2099  *
2100  * Note: Drivers cannot rely on userspace to support this property and
2101  * issue a modeset. As such, they may choose to handle issues (like
2102  * re-training a link) without userspace's intervention.
2103  *
2104  * The reason for adding this property is to handle link training failures, but
2105  * it is not limited to DP or link training. For example, if we implement
2106  * asynchronous setcrtc, this property can be used to report any failures in that.
2107  */
2108 void drm_connector_set_link_status_property(struct drm_connector *connector,
2109 					    uint64_t link_status)
2110 {
2111 	struct drm_device *dev = connector->dev;
2112 
2113 	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
2114 	connector->state->link_status = link_status;
2115 	drm_modeset_unlock(&dev->mode_config.connection_mutex);
2116 }
2117 EXPORT_SYMBOL(drm_connector_set_link_status_property);
2118 
2119 /**
2120  * drm_connector_attach_max_bpc_property - attach "max bpc" property
2121  * @connector: connector to attach max bpc property on.
2122  * @min: The minimum bit depth supported by the connector.
2123  * @max: The maximum bit depth supported by the connector.
2124  *
2125  * This is used to add support for limiting the bit depth on a connector.
2126  *
2127  * Returns:
2128  * Zero on success, negative errno on failure.
2129  */
2130 int drm_connector_attach_max_bpc_property(struct drm_connector *connector,
2131 					  int min, int max)
2132 {
2133 	struct drm_device *dev = connector->dev;
2134 	struct drm_property *prop;
2135 
2136 	prop = connector->max_bpc_property;
2137 	if (!prop) {
2138 		prop = drm_property_create_range(dev, 0, "max bpc", min, max);
2139 		if (!prop)
2140 			return -ENOMEM;
2141 
2142 		connector->max_bpc_property = prop;
2143 	}
2144 
2145 	drm_object_attach_property(&connector->base, prop, max);
2146 	connector->state->max_requested_bpc = max;
2147 	connector->state->max_bpc = max;
2148 
2149 	return 0;
2150 }
2151 EXPORT_SYMBOL(drm_connector_attach_max_bpc_property);
2152 
2153 /**
2154  * drm_connector_set_vrr_capable_property - sets the variable refresh rate
2155  * capable property for a connector
2156  * @connector: drm connector
2157  * @capable: True if the connector is variable refresh rate capable
2158  *
2159  * Should be used by atomic drivers to update the indicated support for
2160  * variable refresh rate over a connector.
2161  */
2162 void drm_connector_set_vrr_capable_property(
2163 		struct drm_connector *connector, bool capable)
2164 {
2165 	drm_object_property_set_value(&connector->base,
2166 				      connector->vrr_capable_property,
2167 				      capable);
2168 }
2169 EXPORT_SYMBOL(drm_connector_set_vrr_capable_property);
2170 
2171 /**
2172  * drm_connector_set_panel_orientation - sets the connector's panel_orientation
2173  * @connector: connector for which to set the panel-orientation property.
2174  * @panel_orientation: drm_panel_orientation value to set
2175  *
2176  * This function sets the connector's panel_orientation and attaches
2177  * a "panel orientation" property to the connector.
2178  *
2179  * Calling this function on a connector where the panel_orientation has
2180  * already been set is a no-op (e.g. the orientation has been overridden with
2181  * a kernel commandline option).
2182  *
2183  * It is allowed to call this function with a panel_orientation of
2184  * DRM_MODE_PANEL_ORIENTATION_UNKNOWN, in which case it is a no-op.
2185  *
2186  * Returns:
2187  * Zero on success, negative errno on failure.
2188  */
2189 int drm_connector_set_panel_orientation(
2190 	struct drm_connector *connector,
2191 	enum drm_panel_orientation panel_orientation)
2192 {
2193 	struct drm_device *dev = connector->dev;
2194 	struct drm_display_info *info = &connector->display_info;
2195 	struct drm_property *prop;
2196 
2197 	/* Already set? */
2198 	if (info->panel_orientation != DRM_MODE_PANEL_ORIENTATION_UNKNOWN)
2199 		return 0;
2200 
2201 	/* Don't attach the property if the orientation is unknown */
2202 	if (panel_orientation == DRM_MODE_PANEL_ORIENTATION_UNKNOWN)
2203 		return 0;
2204 
2205 	info->panel_orientation = panel_orientation;
2206 
2207 	prop = dev->mode_config.panel_orientation_property;
2208 	if (!prop) {
2209 		prop = drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
2210 				"panel orientation",
2211 				drm_panel_orientation_enum_list,
2212 				ARRAY_SIZE(drm_panel_orientation_enum_list));
2213 		if (!prop)
2214 			return -ENOMEM;
2215 
2216 		dev->mode_config.panel_orientation_property = prop;
2217 	}
2218 
2219 	drm_object_attach_property(&connector->base, prop,
2220 				   info->panel_orientation);
2221 	return 0;
2222 }
2223 EXPORT_SYMBOL(drm_connector_set_panel_orientation);
2224 
2225 /**
2226  * drm_connector_set_panel_orientation_with_quirk -
2227  *	set the connector's panel_orientation after checking for quirks
2228  * @connector: connector for which to init the panel-orientation property.
2229  * @panel_orientation: drm_panel_orientation value to set
2230  * @width: width in pixels of the panel, used for panel quirk detection
2231  * @height: height in pixels of the panel, used for panel quirk detection
2232  *
2233  * Like drm_connector_set_panel_orientation(), but with a check for platform
2234  * specific (e.g. DMI based) quirks overriding the passed in panel_orientation.
2235  *
2236  * Returns:
2237  * Zero on success, negative errno on failure.
2238  */
2239 int drm_connector_set_panel_orientation_with_quirk(
2240 	struct drm_connector *connector,
2241 	enum drm_panel_orientation panel_orientation,
2242 	int width, int height)
2243 {
2244 	int orientation_quirk;
2245 
2246 	orientation_quirk = drm_get_panel_orientation_quirk(width, height);
2247 	if (orientation_quirk != DRM_MODE_PANEL_ORIENTATION_UNKNOWN)
2248 		panel_orientation = orientation_quirk;
2249 
2250 	return drm_connector_set_panel_orientation(connector,
2251 						   panel_orientation);
2252 }
2253 EXPORT_SYMBOL(drm_connector_set_panel_orientation_with_quirk);
2254 
2255 int drm_connector_set_obj_prop(struct drm_mode_object *obj,
2256 				    struct drm_property *property,
2257 				    uint64_t value)
2258 {
2259 	int ret = -EINVAL;
2260 	struct drm_connector *connector = obj_to_connector(obj);
2261 
2262 	/* Do DPMS ourselves */
2263 	if (property == connector->dev->mode_config.dpms_property) {
2264 		ret = (*connector->funcs->dpms)(connector, (int)value);
2265 	} else if (connector->funcs->set_property)
2266 		ret = connector->funcs->set_property(connector, property, value);
2267 
2268 	if (!ret)
2269 		drm_object_property_set_value(&connector->base, property, value);
2270 	return ret;
2271 }
2272 
2273 int drm_connector_property_set_ioctl(struct drm_device *dev,
2274 				     void *data, struct drm_file *file_priv)
2275 {
2276 	struct drm_mode_connector_set_property *conn_set_prop = data;
2277 	struct drm_mode_obj_set_property obj_set_prop = {
2278 		.value = conn_set_prop->value,
2279 		.prop_id = conn_set_prop->prop_id,
2280 		.obj_id = conn_set_prop->connector_id,
2281 		.obj_type = DRM_MODE_OBJECT_CONNECTOR
2282 	};
2283 
2284 	/* It does all the locking and checking we need */
2285 	return drm_mode_obj_set_property_ioctl(dev, &obj_set_prop, file_priv);
2286 }
2287 
2288 static struct drm_encoder *drm_connector_get_encoder(struct drm_connector *connector)
2289 {
2290 	/* For atomic drivers only state objects are synchronously updated and
2291 	 * protected by modeset locks, so check those first. */
2292 	if (connector->state)
2293 		return connector->state->best_encoder;
2294 	return connector->encoder;
2295 }
2296 
2297 static bool
2298 drm_mode_expose_to_userspace(const struct drm_display_mode *mode,
2299 			     const struct list_head *modes,
2300 			     const struct drm_file *file_priv)
2301 {
2302 	/*
2303 	 * If user-space hasn't configured the driver to expose the stereo 3D
2304 	 * modes, don't expose them.
2305 	 */
2306 	if (!file_priv->stereo_allowed && drm_mode_is_stereo(mode))
2307 		return false;
2308 	/*
2309 	 * If user-space hasn't configured the driver to expose the modes
2310 	 * with aspect-ratio, don't expose them. However if such a mode
2311 	 * is unique, let it be exposed, but reset the aspect-ratio flags
2312 	 * while preparing the list of user-modes.
2313 	 */
2314 	if (!file_priv->aspect_ratio_allowed) {
2315 		const struct drm_display_mode *mode_itr;
2316 
2317 		list_for_each_entry(mode_itr, modes, head) {
2318 			if (mode_itr->expose_to_userspace &&
2319 			    drm_mode_match(mode_itr, mode,
2320 					   DRM_MODE_MATCH_TIMINGS |
2321 					   DRM_MODE_MATCH_CLOCK |
2322 					   DRM_MODE_MATCH_FLAGS |
2323 					   DRM_MODE_MATCH_3D_FLAGS))
2324 				return false;
2325 		}
2326 	}
2327 
2328 	return true;
2329 }
2330 
2331 int drm_mode_getconnector(struct drm_device *dev, void *data,
2332 			  struct drm_file *file_priv)
2333 {
2334 	struct drm_mode_get_connector *out_resp = data;
2335 	struct drm_connector *connector;
2336 	struct drm_encoder *encoder;
2337 	struct drm_display_mode *mode;
2338 	int mode_count = 0;
2339 	int encoders_count = 0;
2340 	int ret = 0;
2341 	int copied = 0;
2342 	struct drm_mode_modeinfo u_mode;
2343 	struct drm_mode_modeinfo __user *mode_ptr;
2344 	uint32_t __user *encoder_ptr;
2345 
2346 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
2347 		return -EOPNOTSUPP;
2348 
2349 	memset(&u_mode, 0, sizeof(struct drm_mode_modeinfo));
2350 
2351 	connector = drm_connector_lookup(dev, file_priv, out_resp->connector_id);
2352 	if (!connector)
2353 		return -ENOENT;
2354 
2355 	encoders_count = hweight32(connector->possible_encoders);
2356 
2357 	if ((out_resp->count_encoders >= encoders_count) && encoders_count) {
2358 		copied = 0;
2359 		encoder_ptr = (uint32_t __user *)(unsigned long)(out_resp->encoders_ptr);
2360 
2361 		drm_connector_for_each_possible_encoder(connector, encoder) {
2362 			if (put_user(encoder->base.id, encoder_ptr + copied)) {
2363 				ret = -EFAULT;
2364 				goto out;
2365 			}
2366 			copied++;
2367 		}
2368 	}
2369 	out_resp->count_encoders = encoders_count;
2370 
2371 	out_resp->connector_id = connector->base.id;
2372 	out_resp->connector_type = connector->connector_type;
2373 	out_resp->connector_type_id = connector->connector_type_id;
2374 
2375 	mutex_lock(&dev->mode_config.mutex);
2376 	if (out_resp->count_modes == 0) {
2377 		connector->funcs->fill_modes(connector,
2378 					     dev->mode_config.max_width,
2379 					     dev->mode_config.max_height);
2380 	}
2381 
2382 	out_resp->mm_width = connector->display_info.width_mm;
2383 	out_resp->mm_height = connector->display_info.height_mm;
2384 	out_resp->subpixel = connector->display_info.subpixel_order;
2385 	out_resp->connection = connector->status;
2386 
2387 	/* delayed so we get modes regardless of pre-fill_modes state */
2388 	list_for_each_entry(mode, &connector->modes, head) {
2389 		WARN_ON(mode->expose_to_userspace);
2390 
2391 		if (drm_mode_expose_to_userspace(mode, &connector->modes,
2392 						 file_priv)) {
2393 			mode->expose_to_userspace = true;
2394 			mode_count++;
2395 		}
2396 	}
2397 
2398 	/*
2399 	 * This ioctl is called twice, once to determine how much space is
2400 	 * needed, and the 2nd time to fill it.
2401 	 */
2402 	if ((out_resp->count_modes >= mode_count) && mode_count) {
2403 		copied = 0;
2404 		mode_ptr = (struct drm_mode_modeinfo __user *)(unsigned long)out_resp->modes_ptr;
2405 		list_for_each_entry(mode, &connector->modes, head) {
2406 			if (!mode->expose_to_userspace)
2407 				continue;
2408 
2409 			/* Clear the tag for the next time around */
2410 			mode->expose_to_userspace = false;
2411 
2412 			drm_mode_convert_to_umode(&u_mode, mode);
2413 			/*
2414 			 * Reset aspect ratio flags of user-mode, if modes with
2415 			 * aspect-ratio are not supported.
2416 			 */
2417 			if (!file_priv->aspect_ratio_allowed)
2418 				u_mode.flags &= ~DRM_MODE_FLAG_PIC_AR_MASK;
2419 			if (copy_to_user(mode_ptr + copied,
2420 					 &u_mode, sizeof(u_mode))) {
2421 				ret = -EFAULT;
2422 
2423 				/*
2424 				 * Clear the tag for the rest of
2425 				 * the modes for the next time around.
2426 				 */
2427 				list_for_each_entry_continue(mode, &connector->modes, head)
2428 					mode->expose_to_userspace = false;
2429 
2430 				mutex_unlock(&dev->mode_config.mutex);
2431 
2432 				goto out;
2433 			}
2434 			copied++;
2435 		}
2436 	} else {
2437 		/* Clear the tag for the next time around */
2438 		list_for_each_entry(mode, &connector->modes, head)
2439 			mode->expose_to_userspace = false;
2440 	}
2441 
2442 	out_resp->count_modes = mode_count;
2443 	mutex_unlock(&dev->mode_config.mutex);
2444 
2445 	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
2446 	encoder = drm_connector_get_encoder(connector);
2447 	if (encoder)
2448 		out_resp->encoder_id = encoder->base.id;
2449 	else
2450 		out_resp->encoder_id = 0;
2451 
2452 	/* Only grab properties after probing, to make sure EDID and other
2453 	 * properties reflect the latest status. */
2454 	ret = drm_mode_object_get_properties(&connector->base, file_priv->atomic,
2455 			(uint32_t __user *)(unsigned long)(out_resp->props_ptr),
2456 			(uint64_t __user *)(unsigned long)(out_resp->prop_values_ptr),
2457 			&out_resp->count_props);
2458 	drm_modeset_unlock(&dev->mode_config.connection_mutex);
2459 
2460 out:
2461 	drm_connector_put(connector);
2462 
2463 	return ret;
2464 }
2465 
2466 
2467 /**
2468  * DOC: Tile group
2469  *
2470  * Tile groups are used to represent tiled monitors with a unique integer
2471  * identifier. Tiled monitors using DisplayID v1.3 have a unique 8-byte handle,
2472  * we store this in a tile group, so we have a common identifier for all tiles
2473  * in a monitor group. The property is called "TILE". Drivers can manage tile
2474  * groups using drm_mode_create_tile_group(), drm_mode_put_tile_group() and
2475  * drm_mode_get_tile_group(). But this is only needed for internal panels where
2476  * the tile group information is exposed through a non-standard way.
2477  */
2478 
2479 static void drm_tile_group_free(struct kref *kref)
2480 {
2481 	struct drm_tile_group *tg = container_of(kref, struct drm_tile_group, refcount);
2482 	struct drm_device *dev = tg->dev;
2483 
2484 	mutex_lock(&dev->mode_config.idr_mutex);
2485 	idr_remove(&dev->mode_config.tile_idr, tg->id);
2486 	mutex_unlock(&dev->mode_config.idr_mutex);
2487 	kfree(tg);
2488 }
2489 
2490 /**
2491  * drm_mode_put_tile_group - drop a reference to a tile group.
2492  * @dev: DRM device
2493  * @tg: tile group to drop reference to.
2494  *
2495  * drop reference to tile group and free if 0.
2496  */
2497 void drm_mode_put_tile_group(struct drm_device *dev,
2498 			     struct drm_tile_group *tg)
2499 {
2500 	kref_put(&tg->refcount, drm_tile_group_free);
2501 }
2502 EXPORT_SYMBOL(drm_mode_put_tile_group);
2503 
2504 /**
2505  * drm_mode_get_tile_group - get a reference to an existing tile group
2506  * @dev: DRM device
2507  * @topology: 8-bytes unique per monitor.
2508  *
2509  * Use the unique bytes to get a reference to an existing tile group.
2510  *
2511  * RETURNS:
2512  * tile group or NULL if not found.
2513  */
2514 struct drm_tile_group *drm_mode_get_tile_group(struct drm_device *dev,
2515 					       const char topology[8])
2516 {
2517 	struct drm_tile_group *tg;
2518 	int id;
2519 
2520 	mutex_lock(&dev->mode_config.idr_mutex);
2521 	idr_for_each_entry(&dev->mode_config.tile_idr, tg, id) {
2522 		if (!memcmp(tg->group_data, topology, 8)) {
2523 			if (!kref_get_unless_zero(&tg->refcount))
2524 				tg = NULL;
2525 			mutex_unlock(&dev->mode_config.idr_mutex);
2526 			return tg;
2527 		}
2528 	}
2529 	mutex_unlock(&dev->mode_config.idr_mutex);
2530 	return NULL;
2531 }
2532 EXPORT_SYMBOL(drm_mode_get_tile_group);
2533 
2534 /**
2535  * drm_mode_create_tile_group - create a tile group from a displayid description
2536  * @dev: DRM device
2537  * @topology: 8-bytes unique per monitor.
2538  *
2539  * Create a tile group for the unique monitor, and get a unique
2540  * identifier for the tile group.
2541  *
2542  * RETURNS:
2543  * new tile group or NULL.
2544  */
2545 struct drm_tile_group *drm_mode_create_tile_group(struct drm_device *dev,
2546 						  const char topology[8])
2547 {
2548 	struct drm_tile_group *tg;
2549 	int ret;
2550 
2551 	tg = kzalloc(sizeof(*tg), GFP_KERNEL);
2552 	if (!tg)
2553 		return NULL;
2554 
2555 	kref_init(&tg->refcount);
2556 	memcpy(tg->group_data, topology, 8);
2557 	tg->dev = dev;
2558 
2559 	mutex_lock(&dev->mode_config.idr_mutex);
2560 	ret = idr_alloc(&dev->mode_config.tile_idr, tg, 1, 0, GFP_KERNEL);
2561 	if (ret >= 0) {
2562 		tg->id = ret;
2563 	} else {
2564 		kfree(tg);
2565 		tg = NULL;
2566 	}
2567 
2568 	mutex_unlock(&dev->mode_config.idr_mutex);
2569 	return tg;
2570 }
2571 EXPORT_SYMBOL(drm_mode_create_tile_group);
2572