xref: /openbmc/linux/drivers/gpu/drm/drm_connector.c (revision 3f58ff6b)
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_auth.h>
24 #include <drm/drm_connector.h>
25 #include <drm/drm_drv.h>
26 #include <drm/drm_edid.h>
27 #include <drm/drm_encoder.h>
28 #include <drm/drm_file.h>
29 #include <drm/drm_managed.h>
30 #include <drm/drm_panel.h>
31 #include <drm/drm_print.h>
32 #include <drm/drm_privacy_screen_consumer.h>
33 #include <drm/drm_sysfs.h>
34 #include <drm/drm_utils.h>
35 
36 #include <linux/fb.h>
37 #include <linux/uaccess.h>
38 
39 #include "drm_crtc_internal.h"
40 #include "drm_internal.h"
41 
42 /**
43  * DOC: overview
44  *
45  * In DRM connectors are the general abstraction for display sinks, and include
46  * also fixed panels or anything else that can display pixels in some form. As
47  * opposed to all other KMS objects representing hardware (like CRTC, encoder or
48  * plane abstractions) connectors can be hotplugged and unplugged at runtime.
49  * Hence they are reference-counted using drm_connector_get() and
50  * drm_connector_put().
51  *
52  * KMS driver must create, initialize, register and attach at a &struct
53  * drm_connector for each such sink. The instance is created as other KMS
54  * objects and initialized by setting the following fields. The connector is
55  * initialized with a call to drm_connector_init() with a pointer to the
56  * &struct drm_connector_funcs and a connector type, and then exposed to
57  * userspace with a call to drm_connector_register().
58  *
59  * Connectors must be attached to an encoder to be used. For devices that map
60  * connectors to encoders 1:1, the connector should be attached at
61  * initialization time with a call to drm_connector_attach_encoder(). The
62  * driver must also set the &drm_connector.encoder field to point to the
63  * attached encoder.
64  *
65  * For connectors which are not fixed (like built-in panels) the driver needs to
66  * support hotplug notifications. The simplest way to do that is by using the
67  * probe helpers, see drm_kms_helper_poll_init() for connectors which don't have
68  * hardware support for hotplug interrupts. Connectors with hardware hotplug
69  * support can instead use e.g. drm_helper_hpd_irq_event().
70  */
71 
72 /*
73  * Global connector list for drm_connector_find_by_fwnode().
74  * Note drm_connector_[un]register() first take connector->lock and then
75  * take the connector_list_lock.
76  */
77 static DEFINE_MUTEX(connector_list_lock);
78 static LIST_HEAD(connector_list);
79 
80 struct drm_conn_prop_enum_list {
81 	int type;
82 	const char *name;
83 	struct ida ida;
84 };
85 
86 /*
87  * Connector and encoder types.
88  */
89 static struct drm_conn_prop_enum_list drm_connector_enum_list[] = {
90 	{ DRM_MODE_CONNECTOR_Unknown, "Unknown" },
91 	{ DRM_MODE_CONNECTOR_VGA, "VGA" },
92 	{ DRM_MODE_CONNECTOR_DVII, "DVI-I" },
93 	{ DRM_MODE_CONNECTOR_DVID, "DVI-D" },
94 	{ DRM_MODE_CONNECTOR_DVIA, "DVI-A" },
95 	{ DRM_MODE_CONNECTOR_Composite, "Composite" },
96 	{ DRM_MODE_CONNECTOR_SVIDEO, "SVIDEO" },
97 	{ DRM_MODE_CONNECTOR_LVDS, "LVDS" },
98 	{ DRM_MODE_CONNECTOR_Component, "Component" },
99 	{ DRM_MODE_CONNECTOR_9PinDIN, "DIN" },
100 	{ DRM_MODE_CONNECTOR_DisplayPort, "DP" },
101 	{ DRM_MODE_CONNECTOR_HDMIA, "HDMI-A" },
102 	{ DRM_MODE_CONNECTOR_HDMIB, "HDMI-B" },
103 	{ DRM_MODE_CONNECTOR_TV, "TV" },
104 	{ DRM_MODE_CONNECTOR_eDP, "eDP" },
105 	{ DRM_MODE_CONNECTOR_VIRTUAL, "Virtual" },
106 	{ DRM_MODE_CONNECTOR_DSI, "DSI" },
107 	{ DRM_MODE_CONNECTOR_DPI, "DPI" },
108 	{ DRM_MODE_CONNECTOR_WRITEBACK, "Writeback" },
109 	{ DRM_MODE_CONNECTOR_SPI, "SPI" },
110 	{ DRM_MODE_CONNECTOR_USB, "USB" },
111 };
112 
113 void drm_connector_ida_init(void)
114 {
115 	int i;
116 
117 	for (i = 0; i < ARRAY_SIZE(drm_connector_enum_list); i++)
118 		ida_init(&drm_connector_enum_list[i].ida);
119 }
120 
121 void drm_connector_ida_destroy(void)
122 {
123 	int i;
124 
125 	for (i = 0; i < ARRAY_SIZE(drm_connector_enum_list); i++)
126 		ida_destroy(&drm_connector_enum_list[i].ida);
127 }
128 
129 /**
130  * drm_get_connector_type_name - return a string for connector type
131  * @type: The connector type (DRM_MODE_CONNECTOR_*)
132  *
133  * Returns: the name of the connector type, or NULL if the type is not valid.
134  */
135 const char *drm_get_connector_type_name(unsigned int type)
136 {
137 	if (type < ARRAY_SIZE(drm_connector_enum_list))
138 		return drm_connector_enum_list[type].name;
139 
140 	return NULL;
141 }
142 EXPORT_SYMBOL(drm_get_connector_type_name);
143 
144 /**
145  * drm_connector_get_cmdline_mode - reads the user's cmdline mode
146  * @connector: connector to query
147  *
148  * The kernel supports per-connector configuration of its consoles through
149  * use of the video= parameter. This function parses that option and
150  * extracts the user's specified mode (or enable/disable status) for a
151  * particular connector. This is typically only used during the early fbdev
152  * setup.
153  */
154 static void drm_connector_get_cmdline_mode(struct drm_connector *connector)
155 {
156 	struct drm_cmdline_mode *mode = &connector->cmdline_mode;
157 	char *option = NULL;
158 
159 	if (fb_get_options(connector->name, &option))
160 		return;
161 
162 	if (!drm_mode_parse_command_line_for_connector(option,
163 						       connector,
164 						       mode))
165 		return;
166 
167 	if (mode->force) {
168 		DRM_INFO("forcing %s connector %s\n", connector->name,
169 			 drm_get_connector_force_name(mode->force));
170 		connector->force = mode->force;
171 	}
172 
173 	if (mode->panel_orientation != DRM_MODE_PANEL_ORIENTATION_UNKNOWN) {
174 		DRM_INFO("cmdline forces connector %s panel_orientation to %d\n",
175 			 connector->name, mode->panel_orientation);
176 		drm_connector_set_panel_orientation(connector,
177 						    mode->panel_orientation);
178 	}
179 
180 	DRM_DEBUG_KMS("cmdline mode for connector %s %s %dx%d@%dHz%s%s%s\n",
181 		      connector->name, mode->name,
182 		      mode->xres, mode->yres,
183 		      mode->refresh_specified ? mode->refresh : 60,
184 		      mode->rb ? " reduced blanking" : "",
185 		      mode->margins ? " with margins" : "",
186 		      mode->interlace ?  " interlaced" : "");
187 }
188 
189 static void drm_connector_free(struct kref *kref)
190 {
191 	struct drm_connector *connector =
192 		container_of(kref, struct drm_connector, base.refcount);
193 	struct drm_device *dev = connector->dev;
194 
195 	drm_mode_object_unregister(dev, &connector->base);
196 	connector->funcs->destroy(connector);
197 }
198 
199 void drm_connector_free_work_fn(struct work_struct *work)
200 {
201 	struct drm_connector *connector, *n;
202 	struct drm_device *dev =
203 		container_of(work, struct drm_device, mode_config.connector_free_work);
204 	struct drm_mode_config *config = &dev->mode_config;
205 	unsigned long flags;
206 	struct llist_node *freed;
207 
208 	spin_lock_irqsave(&config->connector_list_lock, flags);
209 	freed = llist_del_all(&config->connector_free_list);
210 	spin_unlock_irqrestore(&config->connector_list_lock, flags);
211 
212 	llist_for_each_entry_safe(connector, n, freed, free_node) {
213 		drm_mode_object_unregister(dev, &connector->base);
214 		connector->funcs->destroy(connector);
215 	}
216 }
217 
218 static 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 				struct i2c_adapter *ddc)
223 {
224 	struct drm_mode_config *config = &dev->mode_config;
225 	int ret;
226 	struct ida *connector_ida =
227 		&drm_connector_enum_list[connector_type].ida;
228 
229 	WARN_ON(drm_drv_uses_atomic_modeset(dev) &&
230 		(!funcs->atomic_destroy_state ||
231 		 !funcs->atomic_duplicate_state));
232 
233 	ret = __drm_mode_object_add(dev, &connector->base,
234 				    DRM_MODE_OBJECT_CONNECTOR,
235 				    false, drm_connector_free);
236 	if (ret)
237 		return ret;
238 
239 	connector->base.properties = &connector->properties;
240 	connector->dev = dev;
241 	connector->funcs = funcs;
242 
243 	/* connector index is used with 32bit bitmasks */
244 	ret = ida_alloc_max(&config->connector_ida, 31, GFP_KERNEL);
245 	if (ret < 0) {
246 		DRM_DEBUG_KMS("Failed to allocate %s connector index: %d\n",
247 			      drm_connector_enum_list[connector_type].name,
248 			      ret);
249 		goto out_put;
250 	}
251 	connector->index = ret;
252 	ret = 0;
253 
254 	connector->connector_type = connector_type;
255 	connector->connector_type_id =
256 		ida_alloc_min(connector_ida, 1, GFP_KERNEL);
257 	if (connector->connector_type_id < 0) {
258 		ret = connector->connector_type_id;
259 		goto out_put_id;
260 	}
261 	connector->name =
262 		kasprintf(GFP_KERNEL, "%s-%d",
263 			  drm_connector_enum_list[connector_type].name,
264 			  connector->connector_type_id);
265 	if (!connector->name) {
266 		ret = -ENOMEM;
267 		goto out_put_type_id;
268 	}
269 
270 	/* provide ddc symlink in sysfs */
271 	connector->ddc = ddc;
272 
273 	INIT_LIST_HEAD(&connector->global_connector_list_entry);
274 	INIT_LIST_HEAD(&connector->probed_modes);
275 	INIT_LIST_HEAD(&connector->modes);
276 	mutex_init(&connector->mutex);
277 	mutex_init(&connector->edid_override_mutex);
278 	connector->edid_blob_ptr = NULL;
279 	connector->epoch_counter = 0;
280 	connector->tile_blob_ptr = NULL;
281 	connector->status = connector_status_unknown;
282 	connector->display_info.panel_orientation =
283 		DRM_MODE_PANEL_ORIENTATION_UNKNOWN;
284 
285 	drm_connector_get_cmdline_mode(connector);
286 
287 	/* We should add connectors at the end to avoid upsetting the connector
288 	 * index too much.
289 	 */
290 	spin_lock_irq(&config->connector_list_lock);
291 	list_add_tail(&connector->head, &config->connector_list);
292 	config->num_connector++;
293 	spin_unlock_irq(&config->connector_list_lock);
294 
295 	if (connector_type != DRM_MODE_CONNECTOR_VIRTUAL &&
296 	    connector_type != DRM_MODE_CONNECTOR_WRITEBACK)
297 		drm_connector_attach_edid_property(connector);
298 
299 	drm_object_attach_property(&connector->base,
300 				      config->dpms_property, 0);
301 
302 	drm_object_attach_property(&connector->base,
303 				   config->link_status_property,
304 				   0);
305 
306 	drm_object_attach_property(&connector->base,
307 				   config->non_desktop_property,
308 				   0);
309 	drm_object_attach_property(&connector->base,
310 				   config->tile_property,
311 				   0);
312 
313 	if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
314 		drm_object_attach_property(&connector->base, config->prop_crtc_id, 0);
315 	}
316 
317 	connector->debugfs_entry = NULL;
318 out_put_type_id:
319 	if (ret)
320 		ida_free(connector_ida, connector->connector_type_id);
321 out_put_id:
322 	if (ret)
323 		ida_free(&config->connector_ida, connector->index);
324 out_put:
325 	if (ret)
326 		drm_mode_object_unregister(dev, &connector->base);
327 
328 	return ret;
329 }
330 
331 /**
332  * drm_connector_init - Init a preallocated connector
333  * @dev: DRM device
334  * @connector: the connector to init
335  * @funcs: callbacks for this connector
336  * @connector_type: user visible type of the connector
337  *
338  * Initialises a preallocated connector. Connectors should be
339  * subclassed as part of driver connector objects.
340  *
341  * At driver unload time the driver's &drm_connector_funcs.destroy hook
342  * should call drm_connector_cleanup() and free the connector structure.
343  * The connector structure should not be allocated with devm_kzalloc().
344  *
345  * Note: consider using drmm_connector_init() instead of
346  * drm_connector_init() to let the DRM managed resource infrastructure
347  * take care of cleanup and deallocation.
348  *
349  * Returns:
350  * Zero on success, error code on failure.
351  */
352 int drm_connector_init(struct drm_device *dev,
353 		       struct drm_connector *connector,
354 		       const struct drm_connector_funcs *funcs,
355 		       int connector_type)
356 {
357 	if (drm_WARN_ON(dev, !(funcs && funcs->destroy)))
358 		return -EINVAL;
359 
360 	return __drm_connector_init(dev, connector, funcs, connector_type, NULL);
361 }
362 EXPORT_SYMBOL(drm_connector_init);
363 
364 /**
365  * drm_connector_init_with_ddc - Init a preallocated connector
366  * @dev: DRM device
367  * @connector: the connector to init
368  * @funcs: callbacks for this connector
369  * @connector_type: user visible type of the connector
370  * @ddc: pointer to the associated ddc adapter
371  *
372  * Initialises a preallocated connector. Connectors should be
373  * subclassed as part of driver connector objects.
374  *
375  * At driver unload time the driver's &drm_connector_funcs.destroy hook
376  * should call drm_connector_cleanup() and free the connector structure.
377  * The connector structure should not be allocated with devm_kzalloc().
378  *
379  * Ensures that the ddc field of the connector is correctly set.
380  *
381  * Note: consider using drmm_connector_init() instead of
382  * drm_connector_init_with_ddc() to let the DRM managed resource
383  * infrastructure take care of cleanup and deallocation.
384  *
385  * Returns:
386  * Zero on success, error code on failure.
387  */
388 int drm_connector_init_with_ddc(struct drm_device *dev,
389 				struct drm_connector *connector,
390 				const struct drm_connector_funcs *funcs,
391 				int connector_type,
392 				struct i2c_adapter *ddc)
393 {
394 	if (drm_WARN_ON(dev, !(funcs && funcs->destroy)))
395 		return -EINVAL;
396 
397 	return __drm_connector_init(dev, connector, funcs, connector_type, ddc);
398 }
399 EXPORT_SYMBOL(drm_connector_init_with_ddc);
400 
401 static void drm_connector_cleanup_action(struct drm_device *dev,
402 					 void *ptr)
403 {
404 	struct drm_connector *connector = ptr;
405 
406 	drm_connector_cleanup(connector);
407 }
408 
409 /**
410  * drmm_connector_init - Init a preallocated connector
411  * @dev: DRM device
412  * @connector: the connector to init
413  * @funcs: callbacks for this connector
414  * @connector_type: user visible type of the connector
415  * @ddc: optional pointer to the associated ddc adapter
416  *
417  * Initialises a preallocated connector. Connectors should be
418  * subclassed as part of driver connector objects.
419  *
420  * Cleanup is automatically handled with a call to
421  * drm_connector_cleanup() in a DRM-managed action.
422  *
423  * The connector structure should be allocated with drmm_kzalloc().
424  *
425  * Returns:
426  * Zero on success, error code on failure.
427  */
428 int drmm_connector_init(struct drm_device *dev,
429 			struct drm_connector *connector,
430 			const struct drm_connector_funcs *funcs,
431 			int connector_type,
432 			struct i2c_adapter *ddc)
433 {
434 	int ret;
435 
436 	if (drm_WARN_ON(dev, funcs && funcs->destroy))
437 		return -EINVAL;
438 
439 	ret = __drm_connector_init(dev, connector, funcs, connector_type, ddc);
440 	if (ret)
441 		return ret;
442 
443 	ret = drmm_add_action_or_reset(dev, drm_connector_cleanup_action,
444 				       connector);
445 	if (ret)
446 		return ret;
447 
448 	return 0;
449 }
450 EXPORT_SYMBOL(drmm_connector_init);
451 
452 /**
453  * drm_connector_attach_edid_property - attach edid property.
454  * @connector: the connector
455  *
456  * Some connector types like DRM_MODE_CONNECTOR_VIRTUAL do not get a
457  * edid property attached by default.  This function can be used to
458  * explicitly enable the edid property in these cases.
459  */
460 void drm_connector_attach_edid_property(struct drm_connector *connector)
461 {
462 	struct drm_mode_config *config = &connector->dev->mode_config;
463 
464 	drm_object_attach_property(&connector->base,
465 				   config->edid_property,
466 				   0);
467 }
468 EXPORT_SYMBOL(drm_connector_attach_edid_property);
469 
470 /**
471  * drm_connector_attach_encoder - attach a connector to an encoder
472  * @connector: connector to attach
473  * @encoder: encoder to attach @connector to
474  *
475  * This function links up a connector to an encoder. Note that the routing
476  * restrictions between encoders and crtcs are exposed to userspace through the
477  * possible_clones and possible_crtcs bitmasks.
478  *
479  * Returns:
480  * Zero on success, negative errno on failure.
481  */
482 int drm_connector_attach_encoder(struct drm_connector *connector,
483 				 struct drm_encoder *encoder)
484 {
485 	/*
486 	 * In the past, drivers have attempted to model the static association
487 	 * of connector to encoder in simple connector/encoder devices using a
488 	 * direct assignment of connector->encoder = encoder. This connection
489 	 * is a logical one and the responsibility of the core, so drivers are
490 	 * expected not to mess with this.
491 	 *
492 	 * Note that the error return should've been enough here, but a large
493 	 * majority of drivers ignores the return value, so add in a big WARN
494 	 * to get people's attention.
495 	 */
496 	if (WARN_ON(connector->encoder))
497 		return -EINVAL;
498 
499 	connector->possible_encoders |= drm_encoder_mask(encoder);
500 
501 	return 0;
502 }
503 EXPORT_SYMBOL(drm_connector_attach_encoder);
504 
505 /**
506  * drm_connector_has_possible_encoder - check if the connector and encoder are
507  * associated with each other
508  * @connector: the connector
509  * @encoder: the encoder
510  *
511  * Returns:
512  * True if @encoder is one of the possible encoders for @connector.
513  */
514 bool drm_connector_has_possible_encoder(struct drm_connector *connector,
515 					struct drm_encoder *encoder)
516 {
517 	return connector->possible_encoders & drm_encoder_mask(encoder);
518 }
519 EXPORT_SYMBOL(drm_connector_has_possible_encoder);
520 
521 static void drm_mode_remove(struct drm_connector *connector,
522 			    struct drm_display_mode *mode)
523 {
524 	list_del(&mode->head);
525 	drm_mode_destroy(connector->dev, mode);
526 }
527 
528 /**
529  * drm_connector_cleanup - cleans up an initialised connector
530  * @connector: connector to cleanup
531  *
532  * Cleans up the connector but doesn't free the object.
533  */
534 void drm_connector_cleanup(struct drm_connector *connector)
535 {
536 	struct drm_device *dev = connector->dev;
537 	struct drm_display_mode *mode, *t;
538 
539 	/* The connector should have been removed from userspace long before
540 	 * it is finally destroyed.
541 	 */
542 	if (WARN_ON(connector->registration_state ==
543 		    DRM_CONNECTOR_REGISTERED))
544 		drm_connector_unregister(connector);
545 
546 	if (connector->privacy_screen) {
547 		drm_privacy_screen_put(connector->privacy_screen);
548 		connector->privacy_screen = NULL;
549 	}
550 
551 	if (connector->tile_group) {
552 		drm_mode_put_tile_group(dev, connector->tile_group);
553 		connector->tile_group = NULL;
554 	}
555 
556 	list_for_each_entry_safe(mode, t, &connector->probed_modes, head)
557 		drm_mode_remove(connector, mode);
558 
559 	list_for_each_entry_safe(mode, t, &connector->modes, head)
560 		drm_mode_remove(connector, mode);
561 
562 	ida_free(&drm_connector_enum_list[connector->connector_type].ida,
563 			  connector->connector_type_id);
564 
565 	ida_free(&dev->mode_config.connector_ida, connector->index);
566 
567 	kfree(connector->display_info.bus_formats);
568 	drm_mode_object_unregister(dev, &connector->base);
569 	kfree(connector->name);
570 	connector->name = NULL;
571 	fwnode_handle_put(connector->fwnode);
572 	connector->fwnode = NULL;
573 	spin_lock_irq(&dev->mode_config.connector_list_lock);
574 	list_del(&connector->head);
575 	dev->mode_config.num_connector--;
576 	spin_unlock_irq(&dev->mode_config.connector_list_lock);
577 
578 	WARN_ON(connector->state && !connector->funcs->atomic_destroy_state);
579 	if (connector->state && connector->funcs->atomic_destroy_state)
580 		connector->funcs->atomic_destroy_state(connector,
581 						       connector->state);
582 
583 	mutex_destroy(&connector->mutex);
584 
585 	memset(connector, 0, sizeof(*connector));
586 
587 	if (dev->registered)
588 		drm_sysfs_hotplug_event(dev);
589 }
590 EXPORT_SYMBOL(drm_connector_cleanup);
591 
592 /**
593  * drm_connector_register - register a connector
594  * @connector: the connector to register
595  *
596  * Register userspace interfaces for a connector. Only call this for connectors
597  * which can be hotplugged after drm_dev_register() has been called already,
598  * e.g. DP MST connectors. All other connectors will be registered automatically
599  * when calling drm_dev_register().
600  *
601  * When the connector is no longer available, callers must call
602  * drm_connector_unregister().
603  *
604  * Returns:
605  * Zero on success, error code on failure.
606  */
607 int drm_connector_register(struct drm_connector *connector)
608 {
609 	int ret = 0;
610 
611 	if (!connector->dev->registered)
612 		return 0;
613 
614 	mutex_lock(&connector->mutex);
615 	if (connector->registration_state != DRM_CONNECTOR_INITIALIZING)
616 		goto unlock;
617 
618 	ret = drm_sysfs_connector_add(connector);
619 	if (ret)
620 		goto unlock;
621 
622 	drm_debugfs_connector_add(connector);
623 
624 	if (connector->funcs->late_register) {
625 		ret = connector->funcs->late_register(connector);
626 		if (ret)
627 			goto err_debugfs;
628 	}
629 
630 	drm_mode_object_register(connector->dev, &connector->base);
631 
632 	connector->registration_state = DRM_CONNECTOR_REGISTERED;
633 
634 	/* Let userspace know we have a new connector */
635 	drm_sysfs_connector_hotplug_event(connector);
636 
637 	if (connector->privacy_screen)
638 		drm_privacy_screen_register_notifier(connector->privacy_screen,
639 					   &connector->privacy_screen_notifier);
640 
641 	mutex_lock(&connector_list_lock);
642 	list_add_tail(&connector->global_connector_list_entry, &connector_list);
643 	mutex_unlock(&connector_list_lock);
644 	goto unlock;
645 
646 err_debugfs:
647 	drm_debugfs_connector_remove(connector);
648 	drm_sysfs_connector_remove(connector);
649 unlock:
650 	mutex_unlock(&connector->mutex);
651 	return ret;
652 }
653 EXPORT_SYMBOL(drm_connector_register);
654 
655 /**
656  * drm_connector_unregister - unregister a connector
657  * @connector: the connector to unregister
658  *
659  * Unregister userspace interfaces for a connector. Only call this for
660  * connectors which have been registered explicitly by calling
661  * drm_connector_register().
662  */
663 void drm_connector_unregister(struct drm_connector *connector)
664 {
665 	mutex_lock(&connector->mutex);
666 	if (connector->registration_state != DRM_CONNECTOR_REGISTERED) {
667 		mutex_unlock(&connector->mutex);
668 		return;
669 	}
670 
671 	mutex_lock(&connector_list_lock);
672 	list_del_init(&connector->global_connector_list_entry);
673 	mutex_unlock(&connector_list_lock);
674 
675 	if (connector->privacy_screen)
676 		drm_privacy_screen_unregister_notifier(
677 					connector->privacy_screen,
678 					&connector->privacy_screen_notifier);
679 
680 	if (connector->funcs->early_unregister)
681 		connector->funcs->early_unregister(connector);
682 
683 	drm_sysfs_connector_remove(connector);
684 	drm_debugfs_connector_remove(connector);
685 
686 	connector->registration_state = DRM_CONNECTOR_UNREGISTERED;
687 	mutex_unlock(&connector->mutex);
688 }
689 EXPORT_SYMBOL(drm_connector_unregister);
690 
691 void drm_connector_unregister_all(struct drm_device *dev)
692 {
693 	struct drm_connector *connector;
694 	struct drm_connector_list_iter conn_iter;
695 
696 	drm_connector_list_iter_begin(dev, &conn_iter);
697 	drm_for_each_connector_iter(connector, &conn_iter)
698 		drm_connector_unregister(connector);
699 	drm_connector_list_iter_end(&conn_iter);
700 }
701 
702 int drm_connector_register_all(struct drm_device *dev)
703 {
704 	struct drm_connector *connector;
705 	struct drm_connector_list_iter conn_iter;
706 	int ret = 0;
707 
708 	drm_connector_list_iter_begin(dev, &conn_iter);
709 	drm_for_each_connector_iter(connector, &conn_iter) {
710 		ret = drm_connector_register(connector);
711 		if (ret)
712 			break;
713 	}
714 	drm_connector_list_iter_end(&conn_iter);
715 
716 	if (ret)
717 		drm_connector_unregister_all(dev);
718 	return ret;
719 }
720 
721 /**
722  * drm_get_connector_status_name - return a string for connector status
723  * @status: connector status to compute name of
724  *
725  * In contrast to the other drm_get_*_name functions this one here returns a
726  * const pointer and hence is threadsafe.
727  *
728  * Returns: connector status string
729  */
730 const char *drm_get_connector_status_name(enum drm_connector_status status)
731 {
732 	if (status == connector_status_connected)
733 		return "connected";
734 	else if (status == connector_status_disconnected)
735 		return "disconnected";
736 	else
737 		return "unknown";
738 }
739 EXPORT_SYMBOL(drm_get_connector_status_name);
740 
741 /**
742  * drm_get_connector_force_name - return a string for connector force
743  * @force: connector force to get name of
744  *
745  * Returns: const pointer to name.
746  */
747 const char *drm_get_connector_force_name(enum drm_connector_force force)
748 {
749 	switch (force) {
750 	case DRM_FORCE_UNSPECIFIED:
751 		return "unspecified";
752 	case DRM_FORCE_OFF:
753 		return "off";
754 	case DRM_FORCE_ON:
755 		return "on";
756 	case DRM_FORCE_ON_DIGITAL:
757 		return "digital";
758 	default:
759 		return "unknown";
760 	}
761 }
762 
763 #ifdef CONFIG_LOCKDEP
764 static struct lockdep_map connector_list_iter_dep_map = {
765 	.name = "drm_connector_list_iter"
766 };
767 #endif
768 
769 /**
770  * drm_connector_list_iter_begin - initialize a connector_list iterator
771  * @dev: DRM device
772  * @iter: connector_list iterator
773  *
774  * Sets @iter up to walk the &drm_mode_config.connector_list of @dev. @iter
775  * must always be cleaned up again by calling drm_connector_list_iter_end().
776  * Iteration itself happens using drm_connector_list_iter_next() or
777  * drm_for_each_connector_iter().
778  */
779 void drm_connector_list_iter_begin(struct drm_device *dev,
780 				   struct drm_connector_list_iter *iter)
781 {
782 	iter->dev = dev;
783 	iter->conn = NULL;
784 	lock_acquire_shared_recursive(&connector_list_iter_dep_map, 0, 1, NULL, _RET_IP_);
785 }
786 EXPORT_SYMBOL(drm_connector_list_iter_begin);
787 
788 /*
789  * Extra-safe connector put function that works in any context. Should only be
790  * used from the connector_iter functions, where we never really expect to
791  * actually release the connector when dropping our final reference.
792  */
793 static void
794 __drm_connector_put_safe(struct drm_connector *conn)
795 {
796 	struct drm_mode_config *config = &conn->dev->mode_config;
797 
798 	lockdep_assert_held(&config->connector_list_lock);
799 
800 	if (!refcount_dec_and_test(&conn->base.refcount.refcount))
801 		return;
802 
803 	llist_add(&conn->free_node, &config->connector_free_list);
804 	schedule_work(&config->connector_free_work);
805 }
806 
807 /**
808  * drm_connector_list_iter_next - return next connector
809  * @iter: connector_list iterator
810  *
811  * Returns: the next connector for @iter, or NULL when the list walk has
812  * completed.
813  */
814 struct drm_connector *
815 drm_connector_list_iter_next(struct drm_connector_list_iter *iter)
816 {
817 	struct drm_connector *old_conn = iter->conn;
818 	struct drm_mode_config *config = &iter->dev->mode_config;
819 	struct list_head *lhead;
820 	unsigned long flags;
821 
822 	spin_lock_irqsave(&config->connector_list_lock, flags);
823 	lhead = old_conn ? &old_conn->head : &config->connector_list;
824 
825 	do {
826 		if (lhead->next == &config->connector_list) {
827 			iter->conn = NULL;
828 			break;
829 		}
830 
831 		lhead = lhead->next;
832 		iter->conn = list_entry(lhead, struct drm_connector, head);
833 
834 		/* loop until it's not a zombie connector */
835 	} while (!kref_get_unless_zero(&iter->conn->base.refcount));
836 
837 	if (old_conn)
838 		__drm_connector_put_safe(old_conn);
839 	spin_unlock_irqrestore(&config->connector_list_lock, flags);
840 
841 	return iter->conn;
842 }
843 EXPORT_SYMBOL(drm_connector_list_iter_next);
844 
845 /**
846  * drm_connector_list_iter_end - tear down a connector_list iterator
847  * @iter: connector_list iterator
848  *
849  * Tears down @iter and releases any resources (like &drm_connector references)
850  * acquired while walking the list. This must always be called, both when the
851  * iteration completes fully or when it was aborted without walking the entire
852  * list.
853  */
854 void drm_connector_list_iter_end(struct drm_connector_list_iter *iter)
855 {
856 	struct drm_mode_config *config = &iter->dev->mode_config;
857 	unsigned long flags;
858 
859 	iter->dev = NULL;
860 	if (iter->conn) {
861 		spin_lock_irqsave(&config->connector_list_lock, flags);
862 		__drm_connector_put_safe(iter->conn);
863 		spin_unlock_irqrestore(&config->connector_list_lock, flags);
864 	}
865 	lock_release(&connector_list_iter_dep_map, _RET_IP_);
866 }
867 EXPORT_SYMBOL(drm_connector_list_iter_end);
868 
869 static const struct drm_prop_enum_list drm_subpixel_enum_list[] = {
870 	{ SubPixelUnknown, "Unknown" },
871 	{ SubPixelHorizontalRGB, "Horizontal RGB" },
872 	{ SubPixelHorizontalBGR, "Horizontal BGR" },
873 	{ SubPixelVerticalRGB, "Vertical RGB" },
874 	{ SubPixelVerticalBGR, "Vertical BGR" },
875 	{ SubPixelNone, "None" },
876 };
877 
878 /**
879  * drm_get_subpixel_order_name - return a string for a given subpixel enum
880  * @order: enum of subpixel_order
881  *
882  * Note you could abuse this and return something out of bounds, but that
883  * would be a caller error.  No unscrubbed user data should make it here.
884  *
885  * Returns: string describing an enumerated subpixel property
886  */
887 const char *drm_get_subpixel_order_name(enum subpixel_order order)
888 {
889 	return drm_subpixel_enum_list[order].name;
890 }
891 EXPORT_SYMBOL(drm_get_subpixel_order_name);
892 
893 static const struct drm_prop_enum_list drm_dpms_enum_list[] = {
894 	{ DRM_MODE_DPMS_ON, "On" },
895 	{ DRM_MODE_DPMS_STANDBY, "Standby" },
896 	{ DRM_MODE_DPMS_SUSPEND, "Suspend" },
897 	{ DRM_MODE_DPMS_OFF, "Off" }
898 };
899 DRM_ENUM_NAME_FN(drm_get_dpms_name, drm_dpms_enum_list)
900 
901 static const struct drm_prop_enum_list drm_link_status_enum_list[] = {
902 	{ DRM_MODE_LINK_STATUS_GOOD, "Good" },
903 	{ DRM_MODE_LINK_STATUS_BAD, "Bad" },
904 };
905 
906 /**
907  * drm_display_info_set_bus_formats - set the supported bus formats
908  * @info: display info to store bus formats in
909  * @formats: array containing the supported bus formats
910  * @num_formats: the number of entries in the fmts array
911  *
912  * Store the supported bus formats in display info structure.
913  * See MEDIA_BUS_FMT_* definitions in include/uapi/linux/media-bus-format.h for
914  * a full list of available formats.
915  *
916  * Returns:
917  * 0 on success or a negative error code on failure.
918  */
919 int drm_display_info_set_bus_formats(struct drm_display_info *info,
920 				     const u32 *formats,
921 				     unsigned int num_formats)
922 {
923 	u32 *fmts = NULL;
924 
925 	if (!formats && num_formats)
926 		return -EINVAL;
927 
928 	if (formats && num_formats) {
929 		fmts = kmemdup(formats, sizeof(*formats) * num_formats,
930 			       GFP_KERNEL);
931 		if (!fmts)
932 			return -ENOMEM;
933 	}
934 
935 	kfree(info->bus_formats);
936 	info->bus_formats = fmts;
937 	info->num_bus_formats = num_formats;
938 
939 	return 0;
940 }
941 EXPORT_SYMBOL(drm_display_info_set_bus_formats);
942 
943 /* Optional connector properties. */
944 static const struct drm_prop_enum_list drm_scaling_mode_enum_list[] = {
945 	{ DRM_MODE_SCALE_NONE, "None" },
946 	{ DRM_MODE_SCALE_FULLSCREEN, "Full" },
947 	{ DRM_MODE_SCALE_CENTER, "Center" },
948 	{ DRM_MODE_SCALE_ASPECT, "Full aspect" },
949 };
950 
951 static const struct drm_prop_enum_list drm_aspect_ratio_enum_list[] = {
952 	{ DRM_MODE_PICTURE_ASPECT_NONE, "Automatic" },
953 	{ DRM_MODE_PICTURE_ASPECT_4_3, "4:3" },
954 	{ DRM_MODE_PICTURE_ASPECT_16_9, "16:9" },
955 };
956 
957 static const struct drm_prop_enum_list drm_content_type_enum_list[] = {
958 	{ DRM_MODE_CONTENT_TYPE_NO_DATA, "No Data" },
959 	{ DRM_MODE_CONTENT_TYPE_GRAPHICS, "Graphics" },
960 	{ DRM_MODE_CONTENT_TYPE_PHOTO, "Photo" },
961 	{ DRM_MODE_CONTENT_TYPE_CINEMA, "Cinema" },
962 	{ DRM_MODE_CONTENT_TYPE_GAME, "Game" },
963 };
964 
965 static const struct drm_prop_enum_list drm_panel_orientation_enum_list[] = {
966 	{ DRM_MODE_PANEL_ORIENTATION_NORMAL,	"Normal"	},
967 	{ DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP,	"Upside Down"	},
968 	{ DRM_MODE_PANEL_ORIENTATION_LEFT_UP,	"Left Side Up"	},
969 	{ DRM_MODE_PANEL_ORIENTATION_RIGHT_UP,	"Right Side Up"	},
970 };
971 
972 static const struct drm_prop_enum_list drm_dvi_i_select_enum_list[] = {
973 	{ DRM_MODE_SUBCONNECTOR_Automatic, "Automatic" }, /* DVI-I and TV-out */
974 	{ DRM_MODE_SUBCONNECTOR_DVID,      "DVI-D"     }, /* DVI-I  */
975 	{ DRM_MODE_SUBCONNECTOR_DVIA,      "DVI-A"     }, /* DVI-I  */
976 };
977 DRM_ENUM_NAME_FN(drm_get_dvi_i_select_name, drm_dvi_i_select_enum_list)
978 
979 static const struct drm_prop_enum_list drm_dvi_i_subconnector_enum_list[] = {
980 	{ DRM_MODE_SUBCONNECTOR_Unknown,   "Unknown"   }, /* DVI-I, TV-out and DP */
981 	{ DRM_MODE_SUBCONNECTOR_DVID,      "DVI-D"     }, /* DVI-I  */
982 	{ DRM_MODE_SUBCONNECTOR_DVIA,      "DVI-A"     }, /* DVI-I  */
983 };
984 DRM_ENUM_NAME_FN(drm_get_dvi_i_subconnector_name,
985 		 drm_dvi_i_subconnector_enum_list)
986 
987 static const struct drm_prop_enum_list drm_tv_select_enum_list[] = {
988 	{ DRM_MODE_SUBCONNECTOR_Automatic, "Automatic" }, /* DVI-I and TV-out */
989 	{ DRM_MODE_SUBCONNECTOR_Composite, "Composite" }, /* TV-out */
990 	{ DRM_MODE_SUBCONNECTOR_SVIDEO,    "SVIDEO"    }, /* TV-out */
991 	{ DRM_MODE_SUBCONNECTOR_Component, "Component" }, /* TV-out */
992 	{ DRM_MODE_SUBCONNECTOR_SCART,     "SCART"     }, /* TV-out */
993 };
994 DRM_ENUM_NAME_FN(drm_get_tv_select_name, drm_tv_select_enum_list)
995 
996 static const struct drm_prop_enum_list drm_tv_subconnector_enum_list[] = {
997 	{ DRM_MODE_SUBCONNECTOR_Unknown,   "Unknown"   }, /* DVI-I, TV-out and DP */
998 	{ DRM_MODE_SUBCONNECTOR_Composite, "Composite" }, /* TV-out */
999 	{ DRM_MODE_SUBCONNECTOR_SVIDEO,    "SVIDEO"    }, /* TV-out */
1000 	{ DRM_MODE_SUBCONNECTOR_Component, "Component" }, /* TV-out */
1001 	{ DRM_MODE_SUBCONNECTOR_SCART,     "SCART"     }, /* TV-out */
1002 };
1003 DRM_ENUM_NAME_FN(drm_get_tv_subconnector_name,
1004 		 drm_tv_subconnector_enum_list)
1005 
1006 static const struct drm_prop_enum_list drm_dp_subconnector_enum_list[] = {
1007 	{ DRM_MODE_SUBCONNECTOR_Unknown,     "Unknown"   }, /* DVI-I, TV-out and DP */
1008 	{ DRM_MODE_SUBCONNECTOR_VGA,	     "VGA"       }, /* DP */
1009 	{ DRM_MODE_SUBCONNECTOR_DVID,	     "DVI-D"     }, /* DP */
1010 	{ DRM_MODE_SUBCONNECTOR_HDMIA,	     "HDMI"      }, /* DP */
1011 	{ DRM_MODE_SUBCONNECTOR_DisplayPort, "DP"        }, /* DP */
1012 	{ DRM_MODE_SUBCONNECTOR_Wireless,    "Wireless"  }, /* DP */
1013 	{ DRM_MODE_SUBCONNECTOR_Native,	     "Native"    }, /* DP */
1014 };
1015 
1016 DRM_ENUM_NAME_FN(drm_get_dp_subconnector_name,
1017 		 drm_dp_subconnector_enum_list)
1018 
1019 static const struct drm_prop_enum_list hdmi_colorspaces[] = {
1020 	/* For Default case, driver will set the colorspace */
1021 	{ DRM_MODE_COLORIMETRY_DEFAULT, "Default" },
1022 	/* Standard Definition Colorimetry based on CEA 861 */
1023 	{ DRM_MODE_COLORIMETRY_SMPTE_170M_YCC, "SMPTE_170M_YCC" },
1024 	{ DRM_MODE_COLORIMETRY_BT709_YCC, "BT709_YCC" },
1025 	/* Standard Definition Colorimetry based on IEC 61966-2-4 */
1026 	{ DRM_MODE_COLORIMETRY_XVYCC_601, "XVYCC_601" },
1027 	/* High Definition Colorimetry based on IEC 61966-2-4 */
1028 	{ DRM_MODE_COLORIMETRY_XVYCC_709, "XVYCC_709" },
1029 	/* Colorimetry based on IEC 61966-2-1/Amendment 1 */
1030 	{ DRM_MODE_COLORIMETRY_SYCC_601, "SYCC_601" },
1031 	/* Colorimetry based on IEC 61966-2-5 [33] */
1032 	{ DRM_MODE_COLORIMETRY_OPYCC_601, "opYCC_601" },
1033 	/* Colorimetry based on IEC 61966-2-5 */
1034 	{ DRM_MODE_COLORIMETRY_OPRGB, "opRGB" },
1035 	/* Colorimetry based on ITU-R BT.2020 */
1036 	{ DRM_MODE_COLORIMETRY_BT2020_CYCC, "BT2020_CYCC" },
1037 	/* Colorimetry based on ITU-R BT.2020 */
1038 	{ DRM_MODE_COLORIMETRY_BT2020_RGB, "BT2020_RGB" },
1039 	/* Colorimetry based on ITU-R BT.2020 */
1040 	{ DRM_MODE_COLORIMETRY_BT2020_YCC, "BT2020_YCC" },
1041 	/* Added as part of Additional Colorimetry Extension in 861.G */
1042 	{ DRM_MODE_COLORIMETRY_DCI_P3_RGB_D65, "DCI-P3_RGB_D65" },
1043 	{ DRM_MODE_COLORIMETRY_DCI_P3_RGB_THEATER, "DCI-P3_RGB_Theater" },
1044 };
1045 
1046 /*
1047  * As per DP 1.4a spec, 2.2.5.7.5 VSC SDP Payload for Pixel Encoding/Colorimetry
1048  * Format Table 2-120
1049  */
1050 static const struct drm_prop_enum_list dp_colorspaces[] = {
1051 	/* For Default case, driver will set the colorspace */
1052 	{ DRM_MODE_COLORIMETRY_DEFAULT, "Default" },
1053 	{ DRM_MODE_COLORIMETRY_RGB_WIDE_FIXED, "RGB_Wide_Gamut_Fixed_Point" },
1054 	/* Colorimetry based on scRGB (IEC 61966-2-2) */
1055 	{ DRM_MODE_COLORIMETRY_RGB_WIDE_FLOAT, "RGB_Wide_Gamut_Floating_Point" },
1056 	/* Colorimetry based on IEC 61966-2-5 */
1057 	{ DRM_MODE_COLORIMETRY_OPRGB, "opRGB" },
1058 	/* Colorimetry based on SMPTE RP 431-2 */
1059 	{ DRM_MODE_COLORIMETRY_DCI_P3_RGB_D65, "DCI-P3_RGB_D65" },
1060 	/* Colorimetry based on ITU-R BT.2020 */
1061 	{ DRM_MODE_COLORIMETRY_BT2020_RGB, "BT2020_RGB" },
1062 	{ DRM_MODE_COLORIMETRY_BT601_YCC, "BT601_YCC" },
1063 	{ DRM_MODE_COLORIMETRY_BT709_YCC, "BT709_YCC" },
1064 	/* Standard Definition Colorimetry based on IEC 61966-2-4 */
1065 	{ DRM_MODE_COLORIMETRY_XVYCC_601, "XVYCC_601" },
1066 	/* High Definition Colorimetry based on IEC 61966-2-4 */
1067 	{ DRM_MODE_COLORIMETRY_XVYCC_709, "XVYCC_709" },
1068 	/* Colorimetry based on IEC 61966-2-1/Amendment 1 */
1069 	{ DRM_MODE_COLORIMETRY_SYCC_601, "SYCC_601" },
1070 	/* Colorimetry based on IEC 61966-2-5 [33] */
1071 	{ DRM_MODE_COLORIMETRY_OPYCC_601, "opYCC_601" },
1072 	/* Colorimetry based on ITU-R BT.2020 */
1073 	{ DRM_MODE_COLORIMETRY_BT2020_CYCC, "BT2020_CYCC" },
1074 	/* Colorimetry based on ITU-R BT.2020 */
1075 	{ DRM_MODE_COLORIMETRY_BT2020_YCC, "BT2020_YCC" },
1076 };
1077 
1078 /**
1079  * DOC: standard connector properties
1080  *
1081  * DRM connectors have a few standardized properties:
1082  *
1083  * EDID:
1084  * 	Blob property which contains the current EDID read from the sink. This
1085  * 	is useful to parse sink identification information like vendor, model
1086  * 	and serial. Drivers should update this property by calling
1087  * 	drm_connector_update_edid_property(), usually after having parsed
1088  * 	the EDID using drm_add_edid_modes(). Userspace cannot change this
1089  * 	property.
1090  *
1091  * 	User-space should not parse the EDID to obtain information exposed via
1092  * 	other KMS properties (because the kernel might apply limits, quirks or
1093  * 	fixups to the EDID). For instance, user-space should not try to parse
1094  * 	mode lists from the EDID.
1095  * DPMS:
1096  * 	Legacy property for setting the power state of the connector. For atomic
1097  * 	drivers this is only provided for backwards compatibility with existing
1098  * 	drivers, it remaps to controlling the "ACTIVE" property on the CRTC the
1099  * 	connector is linked to. Drivers should never set this property directly,
1100  * 	it is handled by the DRM core by calling the &drm_connector_funcs.dpms
1101  * 	callback. For atomic drivers the remapping to the "ACTIVE" property is
1102  * 	implemented in the DRM core.
1103  *
1104  * 	Note that this property cannot be set through the MODE_ATOMIC ioctl,
1105  * 	userspace must use "ACTIVE" on the CRTC instead.
1106  *
1107  * 	WARNING:
1108  *
1109  * 	For userspace also running on legacy drivers the "DPMS" semantics are a
1110  * 	lot more complicated. First, userspace cannot rely on the "DPMS" value
1111  * 	returned by the GETCONNECTOR actually reflecting reality, because many
1112  * 	drivers fail to update it. For atomic drivers this is taken care of in
1113  * 	drm_atomic_helper_update_legacy_modeset_state().
1114  *
1115  * 	The second issue is that the DPMS state is only well-defined when the
1116  * 	connector is connected to a CRTC. In atomic the DRM core enforces that
1117  * 	"ACTIVE" is off in such a case, no such checks exists for "DPMS".
1118  *
1119  * 	Finally, when enabling an output using the legacy SETCONFIG ioctl then
1120  * 	"DPMS" is forced to ON. But see above, that might not be reflected in
1121  * 	the software value on legacy drivers.
1122  *
1123  * 	Summarizing: Only set "DPMS" when the connector is known to be enabled,
1124  * 	assume that a successful SETCONFIG call also sets "DPMS" to on, and
1125  * 	never read back the value of "DPMS" because it can be incorrect.
1126  * PATH:
1127  * 	Connector path property to identify how this sink is physically
1128  * 	connected. Used by DP MST. This should be set by calling
1129  * 	drm_connector_set_path_property(), in the case of DP MST with the
1130  * 	path property the MST manager created. Userspace cannot change this
1131  * 	property.
1132  * TILE:
1133  * 	Connector tile group property to indicate how a set of DRM connector
1134  * 	compose together into one logical screen. This is used by both high-res
1135  * 	external screens (often only using a single cable, but exposing multiple
1136  * 	DP MST sinks), or high-res integrated panels (like dual-link DSI) which
1137  * 	are not gen-locked. Note that for tiled panels which are genlocked, like
1138  * 	dual-link LVDS or dual-link DSI, the driver should try to not expose the
1139  * 	tiling and virtualise both &drm_crtc and &drm_plane if needed. Drivers
1140  * 	should update this value using drm_connector_set_tile_property().
1141  * 	Userspace cannot change this property.
1142  * link-status:
1143  *      Connector link-status property to indicate the status of link. The
1144  *      default value of link-status is "GOOD". If something fails during or
1145  *      after modeset, the kernel driver may set this to "BAD" and issue a
1146  *      hotplug uevent. Drivers should update this value using
1147  *      drm_connector_set_link_status_property().
1148  *
1149  *      When user-space receives the hotplug uevent and detects a "BAD"
1150  *      link-status, the sink doesn't receive pixels anymore (e.g. the screen
1151  *      becomes completely black). The list of available modes may have
1152  *      changed. User-space is expected to pick a new mode if the current one
1153  *      has disappeared and perform a new modeset with link-status set to
1154  *      "GOOD" to re-enable the connector.
1155  *
1156  *      If multiple connectors share the same CRTC and one of them gets a "BAD"
1157  *      link-status, the other are unaffected (ie. the sinks still continue to
1158  *      receive pixels).
1159  *
1160  *      When user-space performs an atomic commit on a connector with a "BAD"
1161  *      link-status without resetting the property to "GOOD", the sink may
1162  *      still not receive pixels. When user-space performs an atomic commit
1163  *      which resets the link-status property to "GOOD" without the
1164  *      ALLOW_MODESET flag set, it might fail because a modeset is required.
1165  *
1166  *      User-space can only change link-status to "GOOD", changing it to "BAD"
1167  *      is a no-op.
1168  *
1169  *      For backwards compatibility with non-atomic userspace the kernel
1170  *      tries to automatically set the link-status back to "GOOD" in the
1171  *      SETCRTC IOCTL. This might fail if the mode is no longer valid, similar
1172  *      to how it might fail if a different screen has been connected in the
1173  *      interim.
1174  * non_desktop:
1175  * 	Indicates the output should be ignored for purposes of displaying a
1176  * 	standard desktop environment or console. This is most likely because
1177  * 	the output device is not rectilinear.
1178  * Content Protection:
1179  *	This property is used by userspace to request the kernel protect future
1180  *	content communicated over the link. When requested, kernel will apply
1181  *	the appropriate means of protection (most often HDCP), and use the
1182  *	property to tell userspace the protection is active.
1183  *
1184  *	Drivers can set this up by calling
1185  *	drm_connector_attach_content_protection_property() on initialization.
1186  *
1187  *	The value of this property can be one of the following:
1188  *
1189  *	DRM_MODE_CONTENT_PROTECTION_UNDESIRED = 0
1190  *		The link is not protected, content is transmitted in the clear.
1191  *	DRM_MODE_CONTENT_PROTECTION_DESIRED = 1
1192  *		Userspace has requested content protection, but the link is not
1193  *		currently protected. When in this state, kernel should enable
1194  *		Content Protection as soon as possible.
1195  *	DRM_MODE_CONTENT_PROTECTION_ENABLED = 2
1196  *		Userspace has requested content protection, and the link is
1197  *		protected. Only the driver can set the property to this value.
1198  *		If userspace attempts to set to ENABLED, kernel will return
1199  *		-EINVAL.
1200  *
1201  *	A few guidelines:
1202  *
1203  *	- DESIRED state should be preserved until userspace de-asserts it by
1204  *	  setting the property to UNDESIRED. This means ENABLED should only
1205  *	  transition to UNDESIRED when the user explicitly requests it.
1206  *	- If the state is DESIRED, kernel should attempt to re-authenticate the
1207  *	  link whenever possible. This includes across disable/enable, dpms,
1208  *	  hotplug, downstream device changes, link status failures, etc..
1209  *	- Kernel sends uevent with the connector id and property id through
1210  *	  @drm_hdcp_update_content_protection, upon below kernel triggered
1211  *	  scenarios:
1212  *
1213  *		- DESIRED -> ENABLED (authentication success)
1214  *		- ENABLED -> DESIRED (termination of authentication)
1215  *	- Please note no uevents for userspace triggered property state changes,
1216  *	  which can't fail such as
1217  *
1218  *		- DESIRED/ENABLED -> UNDESIRED
1219  *		- UNDESIRED -> DESIRED
1220  *	- Userspace is responsible for polling the property or listen to uevents
1221  *	  to determine when the value transitions from ENABLED to DESIRED.
1222  *	  This signifies the link is no longer protected and userspace should
1223  *	  take appropriate action (whatever that might be).
1224  *
1225  * HDCP Content Type:
1226  *	This Enum property is used by the userspace to declare the content type
1227  *	of the display stream, to kernel. Here display stream stands for any
1228  *	display content that userspace intended to display through HDCP
1229  *	encryption.
1230  *
1231  *	Content Type of a stream is decided by the owner of the stream, as
1232  *	"HDCP Type0" or "HDCP Type1".
1233  *
1234  *	The value of the property can be one of the below:
1235  *	  - "HDCP Type0": DRM_MODE_HDCP_CONTENT_TYPE0 = 0
1236  *	  - "HDCP Type1": DRM_MODE_HDCP_CONTENT_TYPE1 = 1
1237  *
1238  *	When kernel starts the HDCP authentication (see "Content Protection"
1239  *	for details), it uses the content type in "HDCP Content Type"
1240  *	for performing the HDCP authentication with the display sink.
1241  *
1242  *	Please note in HDCP spec versions, a link can be authenticated with
1243  *	HDCP 2.2 for Content Type 0/Content Type 1. Where as a link can be
1244  *	authenticated with HDCP1.4 only for Content Type 0(though it is implicit
1245  *	in nature. As there is no reference for Content Type in HDCP1.4).
1246  *
1247  *	HDCP2.2 authentication protocol itself takes the "Content Type" as a
1248  *	parameter, which is a input for the DP HDCP2.2 encryption algo.
1249  *
1250  *	In case of Type 0 content protection request, kernel driver can choose
1251  *	either of HDCP spec versions 1.4 and 2.2. When HDCP2.2 is used for
1252  *	"HDCP Type 0", a HDCP 2.2 capable repeater in the downstream can send
1253  *	that content to a HDCP 1.4 authenticated HDCP sink (Type0 link).
1254  *	But if the content is classified as "HDCP Type 1", above mentioned
1255  *	HDCP 2.2 repeater wont send the content to the HDCP sink as it can't
1256  *	authenticate the HDCP1.4 capable sink for "HDCP Type 1".
1257  *
1258  *	Please note userspace can be ignorant of the HDCP versions used by the
1259  *	kernel driver to achieve the "HDCP Content Type".
1260  *
1261  *	At current scenario, classifying a content as Type 1 ensures that the
1262  *	content will be displayed only through the HDCP2.2 encrypted link.
1263  *
1264  *	Note that the HDCP Content Type property is introduced at HDCP 2.2, and
1265  *	defaults to type 0. It is only exposed by drivers supporting HDCP 2.2
1266  *	(hence supporting Type 0 and Type 1). Based on how next versions of
1267  *	HDCP specs are defined content Type could be used for higher versions
1268  *	too.
1269  *
1270  *	If content type is changed when "Content Protection" is not UNDESIRED,
1271  *	then kernel will disable the HDCP and re-enable with new type in the
1272  *	same atomic commit. And when "Content Protection" is ENABLED, it means
1273  *	that link is HDCP authenticated and encrypted, for the transmission of
1274  *	the Type of stream mentioned at "HDCP Content Type".
1275  *
1276  * HDR_OUTPUT_METADATA:
1277  *	Connector property to enable userspace to send HDR Metadata to
1278  *	driver. This metadata is based on the composition and blending
1279  *	policies decided by user, taking into account the hardware and
1280  *	sink capabilities. The driver gets this metadata and creates a
1281  *	Dynamic Range and Mastering Infoframe (DRM) in case of HDMI,
1282  *	SDP packet (Non-audio INFOFRAME SDP v1.3) for DP. This is then
1283  *	sent to sink. This notifies the sink of the upcoming frame's Color
1284  *	Encoding and Luminance parameters.
1285  *
1286  *	Userspace first need to detect the HDR capabilities of sink by
1287  *	reading and parsing the EDID. Details of HDR metadata for HDMI
1288  *	are added in CTA 861.G spec. For DP , its defined in VESA DP
1289  *	Standard v1.4. It needs to then get the metadata information
1290  *	of the video/game/app content which are encoded in HDR (basically
1291  *	using HDR transfer functions). With this information it needs to
1292  *	decide on a blending policy and compose the relevant
1293  *	layers/overlays into a common format. Once this blending is done,
1294  *	userspace will be aware of the metadata of the composed frame to
1295  *	be send to sink. It then uses this property to communicate this
1296  *	metadata to driver which then make a Infoframe packet and sends
1297  *	to sink based on the type of encoder connected.
1298  *
1299  *	Userspace will be responsible to do Tone mapping operation in case:
1300  *		- Some layers are HDR and others are SDR
1301  *		- HDR layers luminance is not same as sink
1302  *
1303  *	It will even need to do colorspace conversion and get all layers
1304  *	to one common colorspace for blending. It can use either GL, Media
1305  *	or display engine to get this done based on the capabilities of the
1306  *	associated hardware.
1307  *
1308  *	Driver expects metadata to be put in &struct hdr_output_metadata
1309  *	structure from userspace. This is received as blob and stored in
1310  *	&drm_connector_state.hdr_output_metadata. It parses EDID and saves the
1311  *	sink metadata in &struct hdr_sink_metadata, as
1312  *	&drm_connector.hdr_sink_metadata.  Driver uses
1313  *	drm_hdmi_infoframe_set_hdr_metadata() helper to set the HDR metadata,
1314  *	hdmi_drm_infoframe_pack() to pack the infoframe as per spec, in case of
1315  *	HDMI encoder.
1316  *
1317  * max bpc:
1318  *	This range property is used by userspace to limit the bit depth. When
1319  *	used the driver would limit the bpc in accordance with the valid range
1320  *	supported by the hardware and sink. Drivers to use the function
1321  *	drm_connector_attach_max_bpc_property() to create and attach the
1322  *	property to the connector during initialization.
1323  *
1324  * Connectors also have one standardized atomic property:
1325  *
1326  * CRTC_ID:
1327  * 	Mode object ID of the &drm_crtc this connector should be connected to.
1328  *
1329  * Connectors for LCD panels may also have one standardized property:
1330  *
1331  * panel orientation:
1332  *	On some devices the LCD panel is mounted in the casing in such a way
1333  *	that the up/top side of the panel does not match with the top side of
1334  *	the device. Userspace can use this property to check for this.
1335  *	Note that input coordinates from touchscreens (input devices with
1336  *	INPUT_PROP_DIRECT) will still map 1:1 to the actual LCD panel
1337  *	coordinates, so if userspace rotates the picture to adjust for
1338  *	the orientation it must also apply the same transformation to the
1339  *	touchscreen input coordinates. This property is initialized by calling
1340  *	drm_connector_set_panel_orientation() or
1341  *	drm_connector_set_panel_orientation_with_quirk()
1342  *
1343  * scaling mode:
1344  *	This property defines how a non-native mode is upscaled to the native
1345  *	mode of an LCD panel:
1346  *
1347  *	None:
1348  *		No upscaling happens, scaling is left to the panel. Not all
1349  *		drivers expose this mode.
1350  *	Full:
1351  *		The output is upscaled to the full resolution of the panel,
1352  *		ignoring the aspect ratio.
1353  *	Center:
1354  *		No upscaling happens, the output is centered within the native
1355  *		resolution the panel.
1356  *	Full aspect:
1357  *		The output is upscaled to maximize either the width or height
1358  *		while retaining the aspect ratio.
1359  *
1360  *	This property should be set up by calling
1361  *	drm_connector_attach_scaling_mode_property(). Note that drivers
1362  *	can also expose this property to external outputs, in which case they
1363  *	must support "None", which should be the default (since external screens
1364  *	have a built-in scaler).
1365  *
1366  * subconnector:
1367  *	This property is used by DVI-I, TVout and DisplayPort to indicate different
1368  *	connector subtypes. Enum values more or less match with those from main
1369  *	connector types.
1370  *	For DVI-I and TVout there is also a matching property "select subconnector"
1371  *	allowing to switch between signal types.
1372  *	DP subconnector corresponds to a downstream port.
1373  *
1374  * privacy-screen sw-state, privacy-screen hw-state:
1375  *	These 2 optional properties can be used to query the state of the
1376  *	electronic privacy screen that is available on some displays; and in
1377  *	some cases also control the state. If a driver implements these
1378  *	properties then both properties must be present.
1379  *
1380  *	"privacy-screen hw-state" is read-only and reflects the actual state
1381  *	of the privacy-screen, possible values: "Enabled", "Disabled,
1382  *	"Enabled-locked", "Disabled-locked". The locked states indicate
1383  *	that the state cannot be changed through the DRM API. E.g. there
1384  *	might be devices where the firmware-setup options, or a hardware
1385  *	slider-switch, offer always on / off modes.
1386  *
1387  *	"privacy-screen sw-state" can be set to change the privacy-screen state
1388  *	when not locked. In this case the driver must update the hw-state
1389  *	property to reflect the new state on completion of the commit of the
1390  *	sw-state property. Setting the sw-state property when the hw-state is
1391  *	locked must be interpreted by the driver as a request to change the
1392  *	state to the set state when the hw-state becomes unlocked. E.g. if
1393  *	"privacy-screen hw-state" is "Enabled-locked" and the sw-state
1394  *	gets set to "Disabled" followed by the user unlocking the state by
1395  *	changing the slider-switch position, then the driver must set the
1396  *	state to "Disabled" upon receiving the unlock event.
1397  *
1398  *	In some cases the privacy-screen's actual state might change outside of
1399  *	control of the DRM code. E.g. there might be a firmware handled hotkey
1400  *	which toggles the actual state, or the actual state might be changed
1401  *	through another userspace API such as writing /proc/acpi/ibm/lcdshadow.
1402  *	In this case the driver must update both the hw-state and the sw-state
1403  *	to reflect the new value, overwriting any pending state requests in the
1404  *	sw-state. Any pending sw-state requests are thus discarded.
1405  *
1406  *	Note that the ability for the state to change outside of control of
1407  *	the DRM master process means that userspace must not cache the value
1408  *	of the sw-state. Caching the sw-state value and including it in later
1409  *	atomic commits may lead to overriding a state change done through e.g.
1410  *	a firmware handled hotkey. Therefor userspace must not include the
1411  *	privacy-screen sw-state in an atomic commit unless it wants to change
1412  *	its value.
1413  */
1414 
1415 int drm_connector_create_standard_properties(struct drm_device *dev)
1416 {
1417 	struct drm_property *prop;
1418 
1419 	prop = drm_property_create(dev, DRM_MODE_PROP_BLOB |
1420 				   DRM_MODE_PROP_IMMUTABLE,
1421 				   "EDID", 0);
1422 	if (!prop)
1423 		return -ENOMEM;
1424 	dev->mode_config.edid_property = prop;
1425 
1426 	prop = drm_property_create_enum(dev, 0,
1427 				   "DPMS", drm_dpms_enum_list,
1428 				   ARRAY_SIZE(drm_dpms_enum_list));
1429 	if (!prop)
1430 		return -ENOMEM;
1431 	dev->mode_config.dpms_property = prop;
1432 
1433 	prop = drm_property_create(dev,
1434 				   DRM_MODE_PROP_BLOB |
1435 				   DRM_MODE_PROP_IMMUTABLE,
1436 				   "PATH", 0);
1437 	if (!prop)
1438 		return -ENOMEM;
1439 	dev->mode_config.path_property = prop;
1440 
1441 	prop = drm_property_create(dev,
1442 				   DRM_MODE_PROP_BLOB |
1443 				   DRM_MODE_PROP_IMMUTABLE,
1444 				   "TILE", 0);
1445 	if (!prop)
1446 		return -ENOMEM;
1447 	dev->mode_config.tile_property = prop;
1448 
1449 	prop = drm_property_create_enum(dev, 0, "link-status",
1450 					drm_link_status_enum_list,
1451 					ARRAY_SIZE(drm_link_status_enum_list));
1452 	if (!prop)
1453 		return -ENOMEM;
1454 	dev->mode_config.link_status_property = prop;
1455 
1456 	prop = drm_property_create_bool(dev, DRM_MODE_PROP_IMMUTABLE, "non-desktop");
1457 	if (!prop)
1458 		return -ENOMEM;
1459 	dev->mode_config.non_desktop_property = prop;
1460 
1461 	prop = drm_property_create(dev, DRM_MODE_PROP_BLOB,
1462 				   "HDR_OUTPUT_METADATA", 0);
1463 	if (!prop)
1464 		return -ENOMEM;
1465 	dev->mode_config.hdr_output_metadata_property = prop;
1466 
1467 	return 0;
1468 }
1469 
1470 /**
1471  * drm_mode_create_dvi_i_properties - create DVI-I specific connector properties
1472  * @dev: DRM device
1473  *
1474  * Called by a driver the first time a DVI-I connector is made.
1475  *
1476  * Returns: %0
1477  */
1478 int drm_mode_create_dvi_i_properties(struct drm_device *dev)
1479 {
1480 	struct drm_property *dvi_i_selector;
1481 	struct drm_property *dvi_i_subconnector;
1482 
1483 	if (dev->mode_config.dvi_i_select_subconnector_property)
1484 		return 0;
1485 
1486 	dvi_i_selector =
1487 		drm_property_create_enum(dev, 0,
1488 				    "select subconnector",
1489 				    drm_dvi_i_select_enum_list,
1490 				    ARRAY_SIZE(drm_dvi_i_select_enum_list));
1491 	dev->mode_config.dvi_i_select_subconnector_property = dvi_i_selector;
1492 
1493 	dvi_i_subconnector = drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
1494 				    "subconnector",
1495 				    drm_dvi_i_subconnector_enum_list,
1496 				    ARRAY_SIZE(drm_dvi_i_subconnector_enum_list));
1497 	dev->mode_config.dvi_i_subconnector_property = dvi_i_subconnector;
1498 
1499 	return 0;
1500 }
1501 EXPORT_SYMBOL(drm_mode_create_dvi_i_properties);
1502 
1503 /**
1504  * drm_connector_attach_dp_subconnector_property - create subconnector property for DP
1505  * @connector: drm_connector to attach property
1506  *
1507  * Called by a driver when DP connector is created.
1508  */
1509 void drm_connector_attach_dp_subconnector_property(struct drm_connector *connector)
1510 {
1511 	struct drm_mode_config *mode_config = &connector->dev->mode_config;
1512 
1513 	if (!mode_config->dp_subconnector_property)
1514 		mode_config->dp_subconnector_property =
1515 			drm_property_create_enum(connector->dev,
1516 				DRM_MODE_PROP_IMMUTABLE,
1517 				"subconnector",
1518 				drm_dp_subconnector_enum_list,
1519 				ARRAY_SIZE(drm_dp_subconnector_enum_list));
1520 
1521 	drm_object_attach_property(&connector->base,
1522 				   mode_config->dp_subconnector_property,
1523 				   DRM_MODE_SUBCONNECTOR_Unknown);
1524 }
1525 EXPORT_SYMBOL(drm_connector_attach_dp_subconnector_property);
1526 
1527 /**
1528  * DOC: HDMI connector properties
1529  *
1530  * content type (HDMI specific):
1531  *	Indicates content type setting to be used in HDMI infoframes to indicate
1532  *	content type for the external device, so that it adjusts its display
1533  *	settings accordingly.
1534  *
1535  *	The value of this property can be one of the following:
1536  *
1537  *	No Data:
1538  *		Content type is unknown
1539  *	Graphics:
1540  *		Content type is graphics
1541  *	Photo:
1542  *		Content type is photo
1543  *	Cinema:
1544  *		Content type is cinema
1545  *	Game:
1546  *		Content type is game
1547  *
1548  *	The meaning of each content type is defined in CTA-861-G table 15.
1549  *
1550  *	Drivers can set up this property by calling
1551  *	drm_connector_attach_content_type_property(). Decoding to
1552  *	infoframe values is done through drm_hdmi_avi_infoframe_content_type().
1553  */
1554 
1555 /**
1556  * drm_connector_attach_content_type_property - attach content-type property
1557  * @connector: connector to attach content type property on.
1558  *
1559  * Called by a driver the first time a HDMI connector is made.
1560  *
1561  * Returns: %0
1562  */
1563 int drm_connector_attach_content_type_property(struct drm_connector *connector)
1564 {
1565 	if (!drm_mode_create_content_type_property(connector->dev))
1566 		drm_object_attach_property(&connector->base,
1567 					   connector->dev->mode_config.content_type_property,
1568 					   DRM_MODE_CONTENT_TYPE_NO_DATA);
1569 	return 0;
1570 }
1571 EXPORT_SYMBOL(drm_connector_attach_content_type_property);
1572 
1573 /**
1574  * drm_connector_attach_tv_margin_properties - attach TV connector margin
1575  * 	properties
1576  * @connector: DRM connector
1577  *
1578  * Called by a driver when it needs to attach TV margin props to a connector.
1579  * Typically used on SDTV and HDMI connectors.
1580  */
1581 void drm_connector_attach_tv_margin_properties(struct drm_connector *connector)
1582 {
1583 	struct drm_device *dev = connector->dev;
1584 
1585 	drm_object_attach_property(&connector->base,
1586 				   dev->mode_config.tv_left_margin_property,
1587 				   0);
1588 	drm_object_attach_property(&connector->base,
1589 				   dev->mode_config.tv_right_margin_property,
1590 				   0);
1591 	drm_object_attach_property(&connector->base,
1592 				   dev->mode_config.tv_top_margin_property,
1593 				   0);
1594 	drm_object_attach_property(&connector->base,
1595 				   dev->mode_config.tv_bottom_margin_property,
1596 				   0);
1597 }
1598 EXPORT_SYMBOL(drm_connector_attach_tv_margin_properties);
1599 
1600 /**
1601  * drm_mode_create_tv_margin_properties - create TV connector margin properties
1602  * @dev: DRM device
1603  *
1604  * Called by a driver's HDMI connector initialization routine, this function
1605  * creates the TV margin properties for a given device. No need to call this
1606  * function for an SDTV connector, it's already called from
1607  * drm_mode_create_tv_properties().
1608  *
1609  * Returns:
1610  * 0 on success or a negative error code on failure.
1611  */
1612 int drm_mode_create_tv_margin_properties(struct drm_device *dev)
1613 {
1614 	if (dev->mode_config.tv_left_margin_property)
1615 		return 0;
1616 
1617 	dev->mode_config.tv_left_margin_property =
1618 		drm_property_create_range(dev, 0, "left margin", 0, 100);
1619 	if (!dev->mode_config.tv_left_margin_property)
1620 		return -ENOMEM;
1621 
1622 	dev->mode_config.tv_right_margin_property =
1623 		drm_property_create_range(dev, 0, "right margin", 0, 100);
1624 	if (!dev->mode_config.tv_right_margin_property)
1625 		return -ENOMEM;
1626 
1627 	dev->mode_config.tv_top_margin_property =
1628 		drm_property_create_range(dev, 0, "top margin", 0, 100);
1629 	if (!dev->mode_config.tv_top_margin_property)
1630 		return -ENOMEM;
1631 
1632 	dev->mode_config.tv_bottom_margin_property =
1633 		drm_property_create_range(dev, 0, "bottom margin", 0, 100);
1634 	if (!dev->mode_config.tv_bottom_margin_property)
1635 		return -ENOMEM;
1636 
1637 	return 0;
1638 }
1639 EXPORT_SYMBOL(drm_mode_create_tv_margin_properties);
1640 
1641 /**
1642  * drm_mode_create_tv_properties - create TV specific connector properties
1643  * @dev: DRM device
1644  * @num_modes: number of different TV formats (modes) supported
1645  * @modes: array of pointers to strings containing name of each format
1646  *
1647  * Called by a driver's TV initialization routine, this function creates
1648  * the TV specific connector properties for a given device.  Caller is
1649  * responsible for allocating a list of format names and passing them to
1650  * this routine.
1651  *
1652  * Returns:
1653  * 0 on success or a negative error code on failure.
1654  */
1655 int drm_mode_create_tv_properties(struct drm_device *dev,
1656 				  unsigned int num_modes,
1657 				  const char * const modes[])
1658 {
1659 	struct drm_property *tv_selector;
1660 	struct drm_property *tv_subconnector;
1661 	unsigned int i;
1662 
1663 	if (dev->mode_config.tv_select_subconnector_property)
1664 		return 0;
1665 
1666 	/*
1667 	 * Basic connector properties
1668 	 */
1669 	tv_selector = drm_property_create_enum(dev, 0,
1670 					  "select subconnector",
1671 					  drm_tv_select_enum_list,
1672 					  ARRAY_SIZE(drm_tv_select_enum_list));
1673 	if (!tv_selector)
1674 		goto nomem;
1675 
1676 	dev->mode_config.tv_select_subconnector_property = tv_selector;
1677 
1678 	tv_subconnector =
1679 		drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
1680 				    "subconnector",
1681 				    drm_tv_subconnector_enum_list,
1682 				    ARRAY_SIZE(drm_tv_subconnector_enum_list));
1683 	if (!tv_subconnector)
1684 		goto nomem;
1685 	dev->mode_config.tv_subconnector_property = tv_subconnector;
1686 
1687 	/*
1688 	 * Other, TV specific properties: margins & TV modes.
1689 	 */
1690 	if (drm_mode_create_tv_margin_properties(dev))
1691 		goto nomem;
1692 
1693 	dev->mode_config.tv_mode_property =
1694 		drm_property_create(dev, DRM_MODE_PROP_ENUM,
1695 				    "mode", num_modes);
1696 	if (!dev->mode_config.tv_mode_property)
1697 		goto nomem;
1698 
1699 	for (i = 0; i < num_modes; i++)
1700 		drm_property_add_enum(dev->mode_config.tv_mode_property,
1701 				      i, modes[i]);
1702 
1703 	dev->mode_config.tv_brightness_property =
1704 		drm_property_create_range(dev, 0, "brightness", 0, 100);
1705 	if (!dev->mode_config.tv_brightness_property)
1706 		goto nomem;
1707 
1708 	dev->mode_config.tv_contrast_property =
1709 		drm_property_create_range(dev, 0, "contrast", 0, 100);
1710 	if (!dev->mode_config.tv_contrast_property)
1711 		goto nomem;
1712 
1713 	dev->mode_config.tv_flicker_reduction_property =
1714 		drm_property_create_range(dev, 0, "flicker reduction", 0, 100);
1715 	if (!dev->mode_config.tv_flicker_reduction_property)
1716 		goto nomem;
1717 
1718 	dev->mode_config.tv_overscan_property =
1719 		drm_property_create_range(dev, 0, "overscan", 0, 100);
1720 	if (!dev->mode_config.tv_overscan_property)
1721 		goto nomem;
1722 
1723 	dev->mode_config.tv_saturation_property =
1724 		drm_property_create_range(dev, 0, "saturation", 0, 100);
1725 	if (!dev->mode_config.tv_saturation_property)
1726 		goto nomem;
1727 
1728 	dev->mode_config.tv_hue_property =
1729 		drm_property_create_range(dev, 0, "hue", 0, 100);
1730 	if (!dev->mode_config.tv_hue_property)
1731 		goto nomem;
1732 
1733 	return 0;
1734 nomem:
1735 	return -ENOMEM;
1736 }
1737 EXPORT_SYMBOL(drm_mode_create_tv_properties);
1738 
1739 /**
1740  * drm_mode_create_scaling_mode_property - create scaling mode property
1741  * @dev: DRM device
1742  *
1743  * Called by a driver the first time it's needed, must be attached to desired
1744  * connectors.
1745  *
1746  * Atomic drivers should use drm_connector_attach_scaling_mode_property()
1747  * instead to correctly assign &drm_connector_state.scaling_mode
1748  * in the atomic state.
1749  *
1750  * Returns: %0
1751  */
1752 int drm_mode_create_scaling_mode_property(struct drm_device *dev)
1753 {
1754 	struct drm_property *scaling_mode;
1755 
1756 	if (dev->mode_config.scaling_mode_property)
1757 		return 0;
1758 
1759 	scaling_mode =
1760 		drm_property_create_enum(dev, 0, "scaling mode",
1761 				drm_scaling_mode_enum_list,
1762 				    ARRAY_SIZE(drm_scaling_mode_enum_list));
1763 
1764 	dev->mode_config.scaling_mode_property = scaling_mode;
1765 
1766 	return 0;
1767 }
1768 EXPORT_SYMBOL(drm_mode_create_scaling_mode_property);
1769 
1770 /**
1771  * DOC: Variable refresh properties
1772  *
1773  * Variable refresh rate capable displays can dynamically adjust their
1774  * refresh rate by extending the duration of their vertical front porch
1775  * until page flip or timeout occurs. This can reduce or remove stuttering
1776  * and latency in scenarios where the page flip does not align with the
1777  * vblank interval.
1778  *
1779  * An example scenario would be an application flipping at a constant rate
1780  * of 48Hz on a 60Hz display. The page flip will frequently miss the vblank
1781  * interval and the same contents will be displayed twice. This can be
1782  * observed as stuttering for content with motion.
1783  *
1784  * If variable refresh rate was active on a display that supported a
1785  * variable refresh range from 35Hz to 60Hz no stuttering would be observable
1786  * for the example scenario. The minimum supported variable refresh rate of
1787  * 35Hz is below the page flip frequency and the vertical front porch can
1788  * be extended until the page flip occurs. The vblank interval will be
1789  * directly aligned to the page flip rate.
1790  *
1791  * Not all userspace content is suitable for use with variable refresh rate.
1792  * Large and frequent changes in vertical front porch duration may worsen
1793  * perceived stuttering for input sensitive applications.
1794  *
1795  * Panel brightness will also vary with vertical front porch duration. Some
1796  * panels may have noticeable differences in brightness between the minimum
1797  * vertical front porch duration and the maximum vertical front porch duration.
1798  * Large and frequent changes in vertical front porch duration may produce
1799  * observable flickering for such panels.
1800  *
1801  * Userspace control for variable refresh rate is supported via properties
1802  * on the &drm_connector and &drm_crtc objects.
1803  *
1804  * "vrr_capable":
1805  *	Optional &drm_connector boolean property that drivers should attach
1806  *	with drm_connector_attach_vrr_capable_property() on connectors that
1807  *	could support variable refresh rates. Drivers should update the
1808  *	property value by calling drm_connector_set_vrr_capable_property().
1809  *
1810  *	Absence of the property should indicate absence of support.
1811  *
1812  * "VRR_ENABLED":
1813  *	Default &drm_crtc boolean property that notifies the driver that the
1814  *	content on the CRTC is suitable for variable refresh rate presentation.
1815  *	The driver will take this property as a hint to enable variable
1816  *	refresh rate support if the receiver supports it, ie. if the
1817  *	"vrr_capable" property is true on the &drm_connector object. The
1818  *	vertical front porch duration will be extended until page-flip or
1819  *	timeout when enabled.
1820  *
1821  *	The minimum vertical front porch duration is defined as the vertical
1822  *	front porch duration for the current mode.
1823  *
1824  *	The maximum vertical front porch duration is greater than or equal to
1825  *	the minimum vertical front porch duration. The duration is derived
1826  *	from the minimum supported variable refresh rate for the connector.
1827  *
1828  *	The driver may place further restrictions within these minimum
1829  *	and maximum bounds.
1830  */
1831 
1832 /**
1833  * drm_connector_attach_vrr_capable_property - creates the
1834  * vrr_capable property
1835  * @connector: connector to create the vrr_capable property on.
1836  *
1837  * This is used by atomic drivers to add support for querying
1838  * variable refresh rate capability for a connector.
1839  *
1840  * Returns:
1841  * Zero on success, negative errno on failure.
1842  */
1843 int drm_connector_attach_vrr_capable_property(
1844 	struct drm_connector *connector)
1845 {
1846 	struct drm_device *dev = connector->dev;
1847 	struct drm_property *prop;
1848 
1849 	if (!connector->vrr_capable_property) {
1850 		prop = drm_property_create_bool(dev, DRM_MODE_PROP_IMMUTABLE,
1851 			"vrr_capable");
1852 		if (!prop)
1853 			return -ENOMEM;
1854 
1855 		connector->vrr_capable_property = prop;
1856 		drm_object_attach_property(&connector->base, prop, 0);
1857 	}
1858 
1859 	return 0;
1860 }
1861 EXPORT_SYMBOL(drm_connector_attach_vrr_capable_property);
1862 
1863 /**
1864  * drm_connector_attach_scaling_mode_property - attach atomic scaling mode property
1865  * @connector: connector to attach scaling mode property on.
1866  * @scaling_mode_mask: or'ed mask of BIT(%DRM_MODE_SCALE_\*).
1867  *
1868  * This is used to add support for scaling mode to atomic drivers.
1869  * The scaling mode will be set to &drm_connector_state.scaling_mode
1870  * and can be used from &drm_connector_helper_funcs->atomic_check for validation.
1871  *
1872  * This is the atomic version of drm_mode_create_scaling_mode_property().
1873  *
1874  * Returns:
1875  * Zero on success, negative errno on failure.
1876  */
1877 int drm_connector_attach_scaling_mode_property(struct drm_connector *connector,
1878 					       u32 scaling_mode_mask)
1879 {
1880 	struct drm_device *dev = connector->dev;
1881 	struct drm_property *scaling_mode_property;
1882 	int i;
1883 	const unsigned valid_scaling_mode_mask =
1884 		(1U << ARRAY_SIZE(drm_scaling_mode_enum_list)) - 1;
1885 
1886 	if (WARN_ON(hweight32(scaling_mode_mask) < 2 ||
1887 		    scaling_mode_mask & ~valid_scaling_mode_mask))
1888 		return -EINVAL;
1889 
1890 	scaling_mode_property =
1891 		drm_property_create(dev, DRM_MODE_PROP_ENUM, "scaling mode",
1892 				    hweight32(scaling_mode_mask));
1893 
1894 	if (!scaling_mode_property)
1895 		return -ENOMEM;
1896 
1897 	for (i = 0; i < ARRAY_SIZE(drm_scaling_mode_enum_list); i++) {
1898 		int ret;
1899 
1900 		if (!(BIT(i) & scaling_mode_mask))
1901 			continue;
1902 
1903 		ret = drm_property_add_enum(scaling_mode_property,
1904 					    drm_scaling_mode_enum_list[i].type,
1905 					    drm_scaling_mode_enum_list[i].name);
1906 
1907 		if (ret) {
1908 			drm_property_destroy(dev, scaling_mode_property);
1909 
1910 			return ret;
1911 		}
1912 	}
1913 
1914 	drm_object_attach_property(&connector->base,
1915 				   scaling_mode_property, 0);
1916 
1917 	connector->scaling_mode_property = scaling_mode_property;
1918 
1919 	return 0;
1920 }
1921 EXPORT_SYMBOL(drm_connector_attach_scaling_mode_property);
1922 
1923 /**
1924  * drm_mode_create_aspect_ratio_property - create aspect ratio property
1925  * @dev: DRM device
1926  *
1927  * Called by a driver the first time it's needed, must be attached to desired
1928  * connectors.
1929  *
1930  * Returns:
1931  * Zero on success, negative errno on failure.
1932  */
1933 int drm_mode_create_aspect_ratio_property(struct drm_device *dev)
1934 {
1935 	if (dev->mode_config.aspect_ratio_property)
1936 		return 0;
1937 
1938 	dev->mode_config.aspect_ratio_property =
1939 		drm_property_create_enum(dev, 0, "aspect ratio",
1940 				drm_aspect_ratio_enum_list,
1941 				ARRAY_SIZE(drm_aspect_ratio_enum_list));
1942 
1943 	if (dev->mode_config.aspect_ratio_property == NULL)
1944 		return -ENOMEM;
1945 
1946 	return 0;
1947 }
1948 EXPORT_SYMBOL(drm_mode_create_aspect_ratio_property);
1949 
1950 /**
1951  * DOC: standard connector properties
1952  *
1953  * Colorspace:
1954  *     This property helps select a suitable colorspace based on the sink
1955  *     capability. Modern sink devices support wider gamut like BT2020.
1956  *     This helps switch to BT2020 mode if the BT2020 encoded video stream
1957  *     is being played by the user, same for any other colorspace. Thereby
1958  *     giving a good visual experience to users.
1959  *
1960  *     The expectation from userspace is that it should parse the EDID
1961  *     and get supported colorspaces. Use this property and switch to the
1962  *     one supported. Sink supported colorspaces should be retrieved by
1963  *     userspace from EDID and driver will not explicitly expose them.
1964  *
1965  *     Basically the expectation from userspace is:
1966  *      - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink
1967  *        colorspace
1968  *      - Set this new property to let the sink know what it
1969  *        converted the CRTC output to.
1970  *      - This property is just to inform sink what colorspace
1971  *        source is trying to drive.
1972  *
1973  * Because between HDMI and DP have different colorspaces,
1974  * drm_mode_create_hdmi_colorspace_property() is used for HDMI connector and
1975  * drm_mode_create_dp_colorspace_property() is used for DP connector.
1976  */
1977 
1978 /**
1979  * drm_mode_create_hdmi_colorspace_property - create hdmi colorspace property
1980  * @connector: connector to create the Colorspace property on.
1981  *
1982  * Called by a driver the first time it's needed, must be attached to desired
1983  * HDMI connectors.
1984  *
1985  * Returns:
1986  * Zero on success, negative errno on failure.
1987  */
1988 int drm_mode_create_hdmi_colorspace_property(struct drm_connector *connector)
1989 {
1990 	struct drm_device *dev = connector->dev;
1991 
1992 	if (connector->colorspace_property)
1993 		return 0;
1994 
1995 	connector->colorspace_property =
1996 		drm_property_create_enum(dev, DRM_MODE_PROP_ENUM, "Colorspace",
1997 					 hdmi_colorspaces,
1998 					 ARRAY_SIZE(hdmi_colorspaces));
1999 
2000 	if (!connector->colorspace_property)
2001 		return -ENOMEM;
2002 
2003 	return 0;
2004 }
2005 EXPORT_SYMBOL(drm_mode_create_hdmi_colorspace_property);
2006 
2007 /**
2008  * drm_mode_create_dp_colorspace_property - create dp colorspace property
2009  * @connector: connector to create the Colorspace property on.
2010  *
2011  * Called by a driver the first time it's needed, must be attached to desired
2012  * DP connectors.
2013  *
2014  * Returns:
2015  * Zero on success, negative errno on failure.
2016  */
2017 int drm_mode_create_dp_colorspace_property(struct drm_connector *connector)
2018 {
2019 	struct drm_device *dev = connector->dev;
2020 
2021 	if (connector->colorspace_property)
2022 		return 0;
2023 
2024 	connector->colorspace_property =
2025 		drm_property_create_enum(dev, DRM_MODE_PROP_ENUM, "Colorspace",
2026 					 dp_colorspaces,
2027 					 ARRAY_SIZE(dp_colorspaces));
2028 
2029 	if (!connector->colorspace_property)
2030 		return -ENOMEM;
2031 
2032 	return 0;
2033 }
2034 EXPORT_SYMBOL(drm_mode_create_dp_colorspace_property);
2035 
2036 /**
2037  * drm_mode_create_content_type_property - create content type property
2038  * @dev: DRM device
2039  *
2040  * Called by a driver the first time it's needed, must be attached to desired
2041  * connectors.
2042  *
2043  * Returns:
2044  * Zero on success, negative errno on failure.
2045  */
2046 int drm_mode_create_content_type_property(struct drm_device *dev)
2047 {
2048 	if (dev->mode_config.content_type_property)
2049 		return 0;
2050 
2051 	dev->mode_config.content_type_property =
2052 		drm_property_create_enum(dev, 0, "content type",
2053 					 drm_content_type_enum_list,
2054 					 ARRAY_SIZE(drm_content_type_enum_list));
2055 
2056 	if (dev->mode_config.content_type_property == NULL)
2057 		return -ENOMEM;
2058 
2059 	return 0;
2060 }
2061 EXPORT_SYMBOL(drm_mode_create_content_type_property);
2062 
2063 /**
2064  * drm_mode_create_suggested_offset_properties - create suggests offset properties
2065  * @dev: DRM device
2066  *
2067  * Create the suggested x/y offset property for connectors.
2068  *
2069  * Returns:
2070  * 0 on success or a negative error code on failure.
2071  */
2072 int drm_mode_create_suggested_offset_properties(struct drm_device *dev)
2073 {
2074 	if (dev->mode_config.suggested_x_property && dev->mode_config.suggested_y_property)
2075 		return 0;
2076 
2077 	dev->mode_config.suggested_x_property =
2078 		drm_property_create_range(dev, DRM_MODE_PROP_IMMUTABLE, "suggested X", 0, 0xffffffff);
2079 
2080 	dev->mode_config.suggested_y_property =
2081 		drm_property_create_range(dev, DRM_MODE_PROP_IMMUTABLE, "suggested Y", 0, 0xffffffff);
2082 
2083 	if (dev->mode_config.suggested_x_property == NULL ||
2084 	    dev->mode_config.suggested_y_property == NULL)
2085 		return -ENOMEM;
2086 	return 0;
2087 }
2088 EXPORT_SYMBOL(drm_mode_create_suggested_offset_properties);
2089 
2090 /**
2091  * drm_connector_set_path_property - set tile property on connector
2092  * @connector: connector to set property on.
2093  * @path: path to use for property; must not be NULL.
2094  *
2095  * This creates a property to expose to userspace to specify a
2096  * connector path. This is mainly used for DisplayPort MST where
2097  * connectors have a topology and we want to allow userspace to give
2098  * them more meaningful names.
2099  *
2100  * Returns:
2101  * Zero on success, negative errno on failure.
2102  */
2103 int drm_connector_set_path_property(struct drm_connector *connector,
2104 				    const char *path)
2105 {
2106 	struct drm_device *dev = connector->dev;
2107 	int ret;
2108 
2109 	ret = drm_property_replace_global_blob(dev,
2110 					       &connector->path_blob_ptr,
2111 					       strlen(path) + 1,
2112 					       path,
2113 					       &connector->base,
2114 					       dev->mode_config.path_property);
2115 	return ret;
2116 }
2117 EXPORT_SYMBOL(drm_connector_set_path_property);
2118 
2119 /**
2120  * drm_connector_set_tile_property - set tile property on connector
2121  * @connector: connector to set property on.
2122  *
2123  * This looks up the tile information for a connector, and creates a
2124  * property for userspace to parse if it exists. The property is of
2125  * the form of 8 integers using ':' as a separator.
2126  * This is used for dual port tiled displays with DisplayPort SST
2127  * or DisplayPort MST connectors.
2128  *
2129  * Returns:
2130  * Zero on success, errno on failure.
2131  */
2132 int drm_connector_set_tile_property(struct drm_connector *connector)
2133 {
2134 	struct drm_device *dev = connector->dev;
2135 	char tile[256];
2136 	int ret;
2137 
2138 	if (!connector->has_tile) {
2139 		ret  = drm_property_replace_global_blob(dev,
2140 							&connector->tile_blob_ptr,
2141 							0,
2142 							NULL,
2143 							&connector->base,
2144 							dev->mode_config.tile_property);
2145 		return ret;
2146 	}
2147 
2148 	snprintf(tile, 256, "%d:%d:%d:%d:%d:%d:%d:%d",
2149 		 connector->tile_group->id, connector->tile_is_single_monitor,
2150 		 connector->num_h_tile, connector->num_v_tile,
2151 		 connector->tile_h_loc, connector->tile_v_loc,
2152 		 connector->tile_h_size, connector->tile_v_size);
2153 
2154 	ret = drm_property_replace_global_blob(dev,
2155 					       &connector->tile_blob_ptr,
2156 					       strlen(tile) + 1,
2157 					       tile,
2158 					       &connector->base,
2159 					       dev->mode_config.tile_property);
2160 	return ret;
2161 }
2162 EXPORT_SYMBOL(drm_connector_set_tile_property);
2163 
2164 /**
2165  * drm_connector_set_link_status_property - Set link status property of a connector
2166  * @connector: drm connector
2167  * @link_status: new value of link status property (0: Good, 1: Bad)
2168  *
2169  * In usual working scenario, this link status property will always be set to
2170  * "GOOD". If something fails during or after a mode set, the kernel driver
2171  * may set this link status property to "BAD". The caller then needs to send a
2172  * hotplug uevent for userspace to re-check the valid modes through
2173  * GET_CONNECTOR_IOCTL and retry modeset.
2174  *
2175  * Note: Drivers cannot rely on userspace to support this property and
2176  * issue a modeset. As such, they may choose to handle issues (like
2177  * re-training a link) without userspace's intervention.
2178  *
2179  * The reason for adding this property is to handle link training failures, but
2180  * it is not limited to DP or link training. For example, if we implement
2181  * asynchronous setcrtc, this property can be used to report any failures in that.
2182  */
2183 void drm_connector_set_link_status_property(struct drm_connector *connector,
2184 					    uint64_t link_status)
2185 {
2186 	struct drm_device *dev = connector->dev;
2187 
2188 	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
2189 	connector->state->link_status = link_status;
2190 	drm_modeset_unlock(&dev->mode_config.connection_mutex);
2191 }
2192 EXPORT_SYMBOL(drm_connector_set_link_status_property);
2193 
2194 /**
2195  * drm_connector_attach_max_bpc_property - attach "max bpc" property
2196  * @connector: connector to attach max bpc property on.
2197  * @min: The minimum bit depth supported by the connector.
2198  * @max: The maximum bit depth supported by the connector.
2199  *
2200  * This is used to add support for limiting the bit depth on a connector.
2201  *
2202  * Returns:
2203  * Zero on success, negative errno on failure.
2204  */
2205 int drm_connector_attach_max_bpc_property(struct drm_connector *connector,
2206 					  int min, int max)
2207 {
2208 	struct drm_device *dev = connector->dev;
2209 	struct drm_property *prop;
2210 
2211 	prop = connector->max_bpc_property;
2212 	if (!prop) {
2213 		prop = drm_property_create_range(dev, 0, "max bpc", min, max);
2214 		if (!prop)
2215 			return -ENOMEM;
2216 
2217 		connector->max_bpc_property = prop;
2218 	}
2219 
2220 	drm_object_attach_property(&connector->base, prop, max);
2221 	connector->state->max_requested_bpc = max;
2222 	connector->state->max_bpc = max;
2223 
2224 	return 0;
2225 }
2226 EXPORT_SYMBOL(drm_connector_attach_max_bpc_property);
2227 
2228 /**
2229  * drm_connector_attach_hdr_output_metadata_property - attach "HDR_OUTPUT_METADA" property
2230  * @connector: connector to attach the property on.
2231  *
2232  * This is used to allow the userspace to send HDR Metadata to the
2233  * driver.
2234  *
2235  * Returns:
2236  * Zero on success, negative errno on failure.
2237  */
2238 int drm_connector_attach_hdr_output_metadata_property(struct drm_connector *connector)
2239 {
2240 	struct drm_device *dev = connector->dev;
2241 	struct drm_property *prop = dev->mode_config.hdr_output_metadata_property;
2242 
2243 	drm_object_attach_property(&connector->base, prop, 0);
2244 
2245 	return 0;
2246 }
2247 EXPORT_SYMBOL(drm_connector_attach_hdr_output_metadata_property);
2248 
2249 /**
2250  * drm_connector_attach_colorspace_property - attach "Colorspace" property
2251  * @connector: connector to attach the property on.
2252  *
2253  * This is used to allow the userspace to signal the output colorspace
2254  * to the driver.
2255  *
2256  * Returns:
2257  * Zero on success, negative errno on failure.
2258  */
2259 int drm_connector_attach_colorspace_property(struct drm_connector *connector)
2260 {
2261 	struct drm_property *prop = connector->colorspace_property;
2262 
2263 	drm_object_attach_property(&connector->base, prop, DRM_MODE_COLORIMETRY_DEFAULT);
2264 
2265 	return 0;
2266 }
2267 EXPORT_SYMBOL(drm_connector_attach_colorspace_property);
2268 
2269 /**
2270  * drm_connector_atomic_hdr_metadata_equal - checks if the hdr metadata changed
2271  * @old_state: old connector state to compare
2272  * @new_state: new connector state to compare
2273  *
2274  * This is used by HDR-enabled drivers to test whether the HDR metadata
2275  * have changed between two different connector state (and thus probably
2276  * requires a full blown mode change).
2277  *
2278  * Returns:
2279  * True if the metadata are equal, False otherwise
2280  */
2281 bool drm_connector_atomic_hdr_metadata_equal(struct drm_connector_state *old_state,
2282 					     struct drm_connector_state *new_state)
2283 {
2284 	struct drm_property_blob *old_blob = old_state->hdr_output_metadata;
2285 	struct drm_property_blob *new_blob = new_state->hdr_output_metadata;
2286 
2287 	if (!old_blob || !new_blob)
2288 		return old_blob == new_blob;
2289 
2290 	if (old_blob->length != new_blob->length)
2291 		return false;
2292 
2293 	return !memcmp(old_blob->data, new_blob->data, old_blob->length);
2294 }
2295 EXPORT_SYMBOL(drm_connector_atomic_hdr_metadata_equal);
2296 
2297 /**
2298  * drm_connector_set_vrr_capable_property - sets the variable refresh rate
2299  * capable property for a connector
2300  * @connector: drm connector
2301  * @capable: True if the connector is variable refresh rate capable
2302  *
2303  * Should be used by atomic drivers to update the indicated support for
2304  * variable refresh rate over a connector.
2305  */
2306 void drm_connector_set_vrr_capable_property(
2307 		struct drm_connector *connector, bool capable)
2308 {
2309 	if (!connector->vrr_capable_property)
2310 		return;
2311 
2312 	drm_object_property_set_value(&connector->base,
2313 				      connector->vrr_capable_property,
2314 				      capable);
2315 }
2316 EXPORT_SYMBOL(drm_connector_set_vrr_capable_property);
2317 
2318 /**
2319  * drm_connector_set_panel_orientation - sets the connector's panel_orientation
2320  * @connector: connector for which to set the panel-orientation property.
2321  * @panel_orientation: drm_panel_orientation value to set
2322  *
2323  * This function sets the connector's panel_orientation and attaches
2324  * a "panel orientation" property to the connector.
2325  *
2326  * Calling this function on a connector where the panel_orientation has
2327  * already been set is a no-op (e.g. the orientation has been overridden with
2328  * a kernel commandline option).
2329  *
2330  * It is allowed to call this function with a panel_orientation of
2331  * DRM_MODE_PANEL_ORIENTATION_UNKNOWN, in which case it is a no-op.
2332  *
2333  * The function shouldn't be called in panel after drm is registered (i.e.
2334  * drm_dev_register() is called in drm).
2335  *
2336  * Returns:
2337  * Zero on success, negative errno on failure.
2338  */
2339 int drm_connector_set_panel_orientation(
2340 	struct drm_connector *connector,
2341 	enum drm_panel_orientation panel_orientation)
2342 {
2343 	struct drm_device *dev = connector->dev;
2344 	struct drm_display_info *info = &connector->display_info;
2345 	struct drm_property *prop;
2346 
2347 	/* Already set? */
2348 	if (info->panel_orientation != DRM_MODE_PANEL_ORIENTATION_UNKNOWN)
2349 		return 0;
2350 
2351 	/* Don't attach the property if the orientation is unknown */
2352 	if (panel_orientation == DRM_MODE_PANEL_ORIENTATION_UNKNOWN)
2353 		return 0;
2354 
2355 	info->panel_orientation = panel_orientation;
2356 
2357 	prop = dev->mode_config.panel_orientation_property;
2358 	if (!prop) {
2359 		prop = drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
2360 				"panel orientation",
2361 				drm_panel_orientation_enum_list,
2362 				ARRAY_SIZE(drm_panel_orientation_enum_list));
2363 		if (!prop)
2364 			return -ENOMEM;
2365 
2366 		dev->mode_config.panel_orientation_property = prop;
2367 	}
2368 
2369 	drm_object_attach_property(&connector->base, prop,
2370 				   info->panel_orientation);
2371 	return 0;
2372 }
2373 EXPORT_SYMBOL(drm_connector_set_panel_orientation);
2374 
2375 /**
2376  * drm_connector_set_panel_orientation_with_quirk - set the
2377  *	connector's panel_orientation after checking for quirks
2378  * @connector: connector for which to init the panel-orientation property.
2379  * @panel_orientation: drm_panel_orientation value to set
2380  * @width: width in pixels of the panel, used for panel quirk detection
2381  * @height: height in pixels of the panel, used for panel quirk detection
2382  *
2383  * Like drm_connector_set_panel_orientation(), but with a check for platform
2384  * specific (e.g. DMI based) quirks overriding the passed in panel_orientation.
2385  *
2386  * Returns:
2387  * Zero on success, negative errno on failure.
2388  */
2389 int drm_connector_set_panel_orientation_with_quirk(
2390 	struct drm_connector *connector,
2391 	enum drm_panel_orientation panel_orientation,
2392 	int width, int height)
2393 {
2394 	int orientation_quirk;
2395 
2396 	orientation_quirk = drm_get_panel_orientation_quirk(width, height);
2397 	if (orientation_quirk != DRM_MODE_PANEL_ORIENTATION_UNKNOWN)
2398 		panel_orientation = orientation_quirk;
2399 
2400 	return drm_connector_set_panel_orientation(connector,
2401 						   panel_orientation);
2402 }
2403 EXPORT_SYMBOL(drm_connector_set_panel_orientation_with_quirk);
2404 
2405 /**
2406  * drm_connector_set_orientation_from_panel -
2407  *	set the connector's panel_orientation from panel's callback.
2408  * @connector: connector for which to init the panel-orientation property.
2409  * @panel: panel that can provide orientation information.
2410  *
2411  * Drm drivers should call this function before drm_dev_register().
2412  * Orientation is obtained from panel's .get_orientation() callback.
2413  *
2414  * Returns:
2415  * Zero on success, negative errno on failure.
2416  */
2417 int drm_connector_set_orientation_from_panel(
2418 	struct drm_connector *connector,
2419 	struct drm_panel *panel)
2420 {
2421 	enum drm_panel_orientation orientation;
2422 
2423 	if (panel && panel->funcs && panel->funcs->get_orientation)
2424 		orientation = panel->funcs->get_orientation(panel);
2425 	else
2426 		orientation = DRM_MODE_PANEL_ORIENTATION_UNKNOWN;
2427 
2428 	return drm_connector_set_panel_orientation(connector, orientation);
2429 }
2430 EXPORT_SYMBOL(drm_connector_set_orientation_from_panel);
2431 
2432 static const struct drm_prop_enum_list privacy_screen_enum[] = {
2433 	{ PRIVACY_SCREEN_DISABLED,		"Disabled" },
2434 	{ PRIVACY_SCREEN_ENABLED,		"Enabled" },
2435 	{ PRIVACY_SCREEN_DISABLED_LOCKED,	"Disabled-locked" },
2436 	{ PRIVACY_SCREEN_ENABLED_LOCKED,	"Enabled-locked" },
2437 };
2438 
2439 /**
2440  * drm_connector_create_privacy_screen_properties - create the drm connecter's
2441  *    privacy-screen properties.
2442  * @connector: connector for which to create the privacy-screen properties
2443  *
2444  * This function creates the "privacy-screen sw-state" and "privacy-screen
2445  * hw-state" properties for the connector. They are not attached.
2446  */
2447 void
2448 drm_connector_create_privacy_screen_properties(struct drm_connector *connector)
2449 {
2450 	if (connector->privacy_screen_sw_state_property)
2451 		return;
2452 
2453 	/* Note sw-state only supports the first 2 values of the enum */
2454 	connector->privacy_screen_sw_state_property =
2455 		drm_property_create_enum(connector->dev, DRM_MODE_PROP_ENUM,
2456 				"privacy-screen sw-state",
2457 				privacy_screen_enum, 2);
2458 
2459 	connector->privacy_screen_hw_state_property =
2460 		drm_property_create_enum(connector->dev,
2461 				DRM_MODE_PROP_IMMUTABLE | DRM_MODE_PROP_ENUM,
2462 				"privacy-screen hw-state",
2463 				privacy_screen_enum,
2464 				ARRAY_SIZE(privacy_screen_enum));
2465 }
2466 EXPORT_SYMBOL(drm_connector_create_privacy_screen_properties);
2467 
2468 /**
2469  * drm_connector_attach_privacy_screen_properties - attach the drm connecter's
2470  *    privacy-screen properties.
2471  * @connector: connector on which to attach the privacy-screen properties
2472  *
2473  * This function attaches the "privacy-screen sw-state" and "privacy-screen
2474  * hw-state" properties to the connector. The initial state of both is set
2475  * to "Disabled".
2476  */
2477 void
2478 drm_connector_attach_privacy_screen_properties(struct drm_connector *connector)
2479 {
2480 	if (!connector->privacy_screen_sw_state_property)
2481 		return;
2482 
2483 	drm_object_attach_property(&connector->base,
2484 				   connector->privacy_screen_sw_state_property,
2485 				   PRIVACY_SCREEN_DISABLED);
2486 
2487 	drm_object_attach_property(&connector->base,
2488 				   connector->privacy_screen_hw_state_property,
2489 				   PRIVACY_SCREEN_DISABLED);
2490 }
2491 EXPORT_SYMBOL(drm_connector_attach_privacy_screen_properties);
2492 
2493 static void drm_connector_update_privacy_screen_properties(
2494 	struct drm_connector *connector, bool set_sw_state)
2495 {
2496 	enum drm_privacy_screen_status sw_state, hw_state;
2497 
2498 	drm_privacy_screen_get_state(connector->privacy_screen,
2499 				     &sw_state, &hw_state);
2500 
2501 	if (set_sw_state)
2502 		connector->state->privacy_screen_sw_state = sw_state;
2503 	drm_object_property_set_value(&connector->base,
2504 			connector->privacy_screen_hw_state_property, hw_state);
2505 }
2506 
2507 static int drm_connector_privacy_screen_notifier(
2508 	struct notifier_block *nb, unsigned long action, void *data)
2509 {
2510 	struct drm_connector *connector =
2511 		container_of(nb, struct drm_connector, privacy_screen_notifier);
2512 	struct drm_device *dev = connector->dev;
2513 
2514 	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
2515 	drm_connector_update_privacy_screen_properties(connector, true);
2516 	drm_modeset_unlock(&dev->mode_config.connection_mutex);
2517 
2518 	drm_sysfs_connector_status_event(connector,
2519 				connector->privacy_screen_sw_state_property);
2520 	drm_sysfs_connector_status_event(connector,
2521 				connector->privacy_screen_hw_state_property);
2522 
2523 	return NOTIFY_DONE;
2524 }
2525 
2526 /**
2527  * drm_connector_attach_privacy_screen_provider - attach a privacy-screen to
2528  *    the connector
2529  * @connector: connector to attach the privacy-screen to
2530  * @priv: drm_privacy_screen to attach
2531  *
2532  * Create and attach the standard privacy-screen properties and register
2533  * a generic notifier for generating sysfs-connector-status-events
2534  * on external changes to the privacy-screen status.
2535  * This function takes ownership of the passed in drm_privacy_screen and will
2536  * call drm_privacy_screen_put() on it when the connector is destroyed.
2537  */
2538 void drm_connector_attach_privacy_screen_provider(
2539 	struct drm_connector *connector, struct drm_privacy_screen *priv)
2540 {
2541 	connector->privacy_screen = priv;
2542 	connector->privacy_screen_notifier.notifier_call =
2543 		drm_connector_privacy_screen_notifier;
2544 
2545 	drm_connector_create_privacy_screen_properties(connector);
2546 	drm_connector_update_privacy_screen_properties(connector, true);
2547 	drm_connector_attach_privacy_screen_properties(connector);
2548 }
2549 EXPORT_SYMBOL(drm_connector_attach_privacy_screen_provider);
2550 
2551 /**
2552  * drm_connector_update_privacy_screen - update connector's privacy-screen sw-state
2553  * @connector_state: connector-state to update the privacy-screen for
2554  *
2555  * This function calls drm_privacy_screen_set_sw_state() on the connector's
2556  * privacy-screen.
2557  *
2558  * If the connector has no privacy-screen, then this is a no-op.
2559  */
2560 void drm_connector_update_privacy_screen(const struct drm_connector_state *connector_state)
2561 {
2562 	struct drm_connector *connector = connector_state->connector;
2563 	int ret;
2564 
2565 	if (!connector->privacy_screen)
2566 		return;
2567 
2568 	ret = drm_privacy_screen_set_sw_state(connector->privacy_screen,
2569 					      connector_state->privacy_screen_sw_state);
2570 	if (ret) {
2571 		drm_err(connector->dev, "Error updating privacy-screen sw_state\n");
2572 		return;
2573 	}
2574 
2575 	/* The hw_state property value may have changed, update it. */
2576 	drm_connector_update_privacy_screen_properties(connector, false);
2577 }
2578 EXPORT_SYMBOL(drm_connector_update_privacy_screen);
2579 
2580 int drm_connector_set_obj_prop(struct drm_mode_object *obj,
2581 				    struct drm_property *property,
2582 				    uint64_t value)
2583 {
2584 	int ret = -EINVAL;
2585 	struct drm_connector *connector = obj_to_connector(obj);
2586 
2587 	/* Do DPMS ourselves */
2588 	if (property == connector->dev->mode_config.dpms_property) {
2589 		ret = (*connector->funcs->dpms)(connector, (int)value);
2590 	} else if (connector->funcs->set_property)
2591 		ret = connector->funcs->set_property(connector, property, value);
2592 
2593 	if (!ret)
2594 		drm_object_property_set_value(&connector->base, property, value);
2595 	return ret;
2596 }
2597 
2598 int drm_connector_property_set_ioctl(struct drm_device *dev,
2599 				     void *data, struct drm_file *file_priv)
2600 {
2601 	struct drm_mode_connector_set_property *conn_set_prop = data;
2602 	struct drm_mode_obj_set_property obj_set_prop = {
2603 		.value = conn_set_prop->value,
2604 		.prop_id = conn_set_prop->prop_id,
2605 		.obj_id = conn_set_prop->connector_id,
2606 		.obj_type = DRM_MODE_OBJECT_CONNECTOR
2607 	};
2608 
2609 	/* It does all the locking and checking we need */
2610 	return drm_mode_obj_set_property_ioctl(dev, &obj_set_prop, file_priv);
2611 }
2612 
2613 static struct drm_encoder *drm_connector_get_encoder(struct drm_connector *connector)
2614 {
2615 	/* For atomic drivers only state objects are synchronously updated and
2616 	 * protected by modeset locks, so check those first.
2617 	 */
2618 	if (connector->state)
2619 		return connector->state->best_encoder;
2620 	return connector->encoder;
2621 }
2622 
2623 static bool
2624 drm_mode_expose_to_userspace(const struct drm_display_mode *mode,
2625 			     const struct list_head *modes,
2626 			     const struct drm_file *file_priv)
2627 {
2628 	/*
2629 	 * If user-space hasn't configured the driver to expose the stereo 3D
2630 	 * modes, don't expose them.
2631 	 */
2632 	if (!file_priv->stereo_allowed && drm_mode_is_stereo(mode))
2633 		return false;
2634 	/*
2635 	 * If user-space hasn't configured the driver to expose the modes
2636 	 * with aspect-ratio, don't expose them. However if such a mode
2637 	 * is unique, let it be exposed, but reset the aspect-ratio flags
2638 	 * while preparing the list of user-modes.
2639 	 */
2640 	if (!file_priv->aspect_ratio_allowed) {
2641 		const struct drm_display_mode *mode_itr;
2642 
2643 		list_for_each_entry(mode_itr, modes, head) {
2644 			if (mode_itr->expose_to_userspace &&
2645 			    drm_mode_match(mode_itr, mode,
2646 					   DRM_MODE_MATCH_TIMINGS |
2647 					   DRM_MODE_MATCH_CLOCK |
2648 					   DRM_MODE_MATCH_FLAGS |
2649 					   DRM_MODE_MATCH_3D_FLAGS))
2650 				return false;
2651 		}
2652 	}
2653 
2654 	return true;
2655 }
2656 
2657 int drm_mode_getconnector(struct drm_device *dev, void *data,
2658 			  struct drm_file *file_priv)
2659 {
2660 	struct drm_mode_get_connector *out_resp = data;
2661 	struct drm_connector *connector;
2662 	struct drm_encoder *encoder;
2663 	struct drm_display_mode *mode;
2664 	int mode_count = 0;
2665 	int encoders_count = 0;
2666 	int ret = 0;
2667 	int copied = 0;
2668 	struct drm_mode_modeinfo u_mode;
2669 	struct drm_mode_modeinfo __user *mode_ptr;
2670 	uint32_t __user *encoder_ptr;
2671 	bool is_current_master;
2672 
2673 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
2674 		return -EOPNOTSUPP;
2675 
2676 	memset(&u_mode, 0, sizeof(struct drm_mode_modeinfo));
2677 
2678 	connector = drm_connector_lookup(dev, file_priv, out_resp->connector_id);
2679 	if (!connector)
2680 		return -ENOENT;
2681 
2682 	encoders_count = hweight32(connector->possible_encoders);
2683 
2684 	if ((out_resp->count_encoders >= encoders_count) && encoders_count) {
2685 		copied = 0;
2686 		encoder_ptr = (uint32_t __user *)(unsigned long)(out_resp->encoders_ptr);
2687 
2688 		drm_connector_for_each_possible_encoder(connector, encoder) {
2689 			if (put_user(encoder->base.id, encoder_ptr + copied)) {
2690 				ret = -EFAULT;
2691 				goto out;
2692 			}
2693 			copied++;
2694 		}
2695 	}
2696 	out_resp->count_encoders = encoders_count;
2697 
2698 	out_resp->connector_id = connector->base.id;
2699 	out_resp->connector_type = connector->connector_type;
2700 	out_resp->connector_type_id = connector->connector_type_id;
2701 
2702 	is_current_master = drm_is_current_master(file_priv);
2703 
2704 	mutex_lock(&dev->mode_config.mutex);
2705 	if (out_resp->count_modes == 0) {
2706 		if (is_current_master)
2707 			connector->funcs->fill_modes(connector,
2708 						     dev->mode_config.max_width,
2709 						     dev->mode_config.max_height);
2710 		else
2711 			drm_dbg_kms(dev, "User-space requested a forced probe on [CONNECTOR:%d:%s] but is not the DRM master, demoting to read-only probe",
2712 				    connector->base.id, connector->name);
2713 	}
2714 
2715 	out_resp->mm_width = connector->display_info.width_mm;
2716 	out_resp->mm_height = connector->display_info.height_mm;
2717 	out_resp->subpixel = connector->display_info.subpixel_order;
2718 	out_resp->connection = connector->status;
2719 
2720 	/* delayed so we get modes regardless of pre-fill_modes state */
2721 	list_for_each_entry(mode, &connector->modes, head) {
2722 		WARN_ON(mode->expose_to_userspace);
2723 
2724 		if (drm_mode_expose_to_userspace(mode, &connector->modes,
2725 						 file_priv)) {
2726 			mode->expose_to_userspace = true;
2727 			mode_count++;
2728 		}
2729 	}
2730 
2731 	/*
2732 	 * This ioctl is called twice, once to determine how much space is
2733 	 * needed, and the 2nd time to fill it.
2734 	 */
2735 	if ((out_resp->count_modes >= mode_count) && mode_count) {
2736 		copied = 0;
2737 		mode_ptr = (struct drm_mode_modeinfo __user *)(unsigned long)out_resp->modes_ptr;
2738 		list_for_each_entry(mode, &connector->modes, head) {
2739 			if (!mode->expose_to_userspace)
2740 				continue;
2741 
2742 			/* Clear the tag for the next time around */
2743 			mode->expose_to_userspace = false;
2744 
2745 			drm_mode_convert_to_umode(&u_mode, mode);
2746 			/*
2747 			 * Reset aspect ratio flags of user-mode, if modes with
2748 			 * aspect-ratio are not supported.
2749 			 */
2750 			if (!file_priv->aspect_ratio_allowed)
2751 				u_mode.flags &= ~DRM_MODE_FLAG_PIC_AR_MASK;
2752 			if (copy_to_user(mode_ptr + copied,
2753 					 &u_mode, sizeof(u_mode))) {
2754 				ret = -EFAULT;
2755 
2756 				/*
2757 				 * Clear the tag for the rest of
2758 				 * the modes for the next time around.
2759 				 */
2760 				list_for_each_entry_continue(mode, &connector->modes, head)
2761 					mode->expose_to_userspace = false;
2762 
2763 				mutex_unlock(&dev->mode_config.mutex);
2764 
2765 				goto out;
2766 			}
2767 			copied++;
2768 		}
2769 	} else {
2770 		/* Clear the tag for the next time around */
2771 		list_for_each_entry(mode, &connector->modes, head)
2772 			mode->expose_to_userspace = false;
2773 	}
2774 
2775 	out_resp->count_modes = mode_count;
2776 	mutex_unlock(&dev->mode_config.mutex);
2777 
2778 	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
2779 	encoder = drm_connector_get_encoder(connector);
2780 	if (encoder)
2781 		out_resp->encoder_id = encoder->base.id;
2782 	else
2783 		out_resp->encoder_id = 0;
2784 
2785 	/* Only grab properties after probing, to make sure EDID and other
2786 	 * properties reflect the latest status.
2787 	 */
2788 	ret = drm_mode_object_get_properties(&connector->base, file_priv->atomic,
2789 			(uint32_t __user *)(unsigned long)(out_resp->props_ptr),
2790 			(uint64_t __user *)(unsigned long)(out_resp->prop_values_ptr),
2791 			&out_resp->count_props);
2792 	drm_modeset_unlock(&dev->mode_config.connection_mutex);
2793 
2794 out:
2795 	drm_connector_put(connector);
2796 
2797 	return ret;
2798 }
2799 
2800 /**
2801  * drm_connector_find_by_fwnode - Find a connector based on the associated fwnode
2802  * @fwnode: fwnode for which to find the matching drm_connector
2803  *
2804  * This functions looks up a drm_connector based on its associated fwnode. When
2805  * a connector is found a reference to the connector is returned. The caller must
2806  * call drm_connector_put() to release this reference when it is done with the
2807  * connector.
2808  *
2809  * Returns: A reference to the found connector or an ERR_PTR().
2810  */
2811 struct drm_connector *drm_connector_find_by_fwnode(struct fwnode_handle *fwnode)
2812 {
2813 	struct drm_connector *connector, *found = ERR_PTR(-ENODEV);
2814 
2815 	if (!fwnode)
2816 		return ERR_PTR(-ENODEV);
2817 
2818 	mutex_lock(&connector_list_lock);
2819 
2820 	list_for_each_entry(connector, &connector_list, global_connector_list_entry) {
2821 		if (connector->fwnode == fwnode ||
2822 		    (connector->fwnode && connector->fwnode->secondary == fwnode)) {
2823 			drm_connector_get(connector);
2824 			found = connector;
2825 			break;
2826 		}
2827 	}
2828 
2829 	mutex_unlock(&connector_list_lock);
2830 
2831 	return found;
2832 }
2833 
2834 /**
2835  * drm_connector_oob_hotplug_event - Report out-of-band hotplug event to connector
2836  * @connector_fwnode: fwnode_handle to report the event on
2837  *
2838  * On some hardware a hotplug event notification may come from outside the display
2839  * driver / device. An example of this is some USB Type-C setups where the hardware
2840  * muxes the DisplayPort data and aux-lines but does not pass the altmode HPD
2841  * status bit to the GPU's DP HPD pin.
2842  *
2843  * This function can be used to report these out-of-band events after obtaining
2844  * a drm_connector reference through calling drm_connector_find_by_fwnode().
2845  */
2846 void drm_connector_oob_hotplug_event(struct fwnode_handle *connector_fwnode)
2847 {
2848 	struct drm_connector *connector;
2849 
2850 	connector = drm_connector_find_by_fwnode(connector_fwnode);
2851 	if (IS_ERR(connector))
2852 		return;
2853 
2854 	if (connector->funcs->oob_hotplug_event)
2855 		connector->funcs->oob_hotplug_event(connector);
2856 
2857 	drm_connector_put(connector);
2858 }
2859 EXPORT_SYMBOL(drm_connector_oob_hotplug_event);
2860 
2861 
2862 /**
2863  * DOC: Tile group
2864  *
2865  * Tile groups are used to represent tiled monitors with a unique integer
2866  * identifier. Tiled monitors using DisplayID v1.3 have a unique 8-byte handle,
2867  * we store this in a tile group, so we have a common identifier for all tiles
2868  * in a monitor group. The property is called "TILE". Drivers can manage tile
2869  * groups using drm_mode_create_tile_group(), drm_mode_put_tile_group() and
2870  * drm_mode_get_tile_group(). But this is only needed for internal panels where
2871  * the tile group information is exposed through a non-standard way.
2872  */
2873 
2874 static void drm_tile_group_free(struct kref *kref)
2875 {
2876 	struct drm_tile_group *tg = container_of(kref, struct drm_tile_group, refcount);
2877 	struct drm_device *dev = tg->dev;
2878 
2879 	mutex_lock(&dev->mode_config.idr_mutex);
2880 	idr_remove(&dev->mode_config.tile_idr, tg->id);
2881 	mutex_unlock(&dev->mode_config.idr_mutex);
2882 	kfree(tg);
2883 }
2884 
2885 /**
2886  * drm_mode_put_tile_group - drop a reference to a tile group.
2887  * @dev: DRM device
2888  * @tg: tile group to drop reference to.
2889  *
2890  * drop reference to tile group and free if 0.
2891  */
2892 void drm_mode_put_tile_group(struct drm_device *dev,
2893 			     struct drm_tile_group *tg)
2894 {
2895 	kref_put(&tg->refcount, drm_tile_group_free);
2896 }
2897 EXPORT_SYMBOL(drm_mode_put_tile_group);
2898 
2899 /**
2900  * drm_mode_get_tile_group - get a reference to an existing tile group
2901  * @dev: DRM device
2902  * @topology: 8-bytes unique per monitor.
2903  *
2904  * Use the unique bytes to get a reference to an existing tile group.
2905  *
2906  * RETURNS:
2907  * tile group or NULL if not found.
2908  */
2909 struct drm_tile_group *drm_mode_get_tile_group(struct drm_device *dev,
2910 					       const char topology[8])
2911 {
2912 	struct drm_tile_group *tg;
2913 	int id;
2914 
2915 	mutex_lock(&dev->mode_config.idr_mutex);
2916 	idr_for_each_entry(&dev->mode_config.tile_idr, tg, id) {
2917 		if (!memcmp(tg->group_data, topology, 8)) {
2918 			if (!kref_get_unless_zero(&tg->refcount))
2919 				tg = NULL;
2920 			mutex_unlock(&dev->mode_config.idr_mutex);
2921 			return tg;
2922 		}
2923 	}
2924 	mutex_unlock(&dev->mode_config.idr_mutex);
2925 	return NULL;
2926 }
2927 EXPORT_SYMBOL(drm_mode_get_tile_group);
2928 
2929 /**
2930  * drm_mode_create_tile_group - create a tile group from a displayid description
2931  * @dev: DRM device
2932  * @topology: 8-bytes unique per monitor.
2933  *
2934  * Create a tile group for the unique monitor, and get a unique
2935  * identifier for the tile group.
2936  *
2937  * RETURNS:
2938  * new tile group or NULL.
2939  */
2940 struct drm_tile_group *drm_mode_create_tile_group(struct drm_device *dev,
2941 						  const char topology[8])
2942 {
2943 	struct drm_tile_group *tg;
2944 	int ret;
2945 
2946 	tg = kzalloc(sizeof(*tg), GFP_KERNEL);
2947 	if (!tg)
2948 		return NULL;
2949 
2950 	kref_init(&tg->refcount);
2951 	memcpy(tg->group_data, topology, 8);
2952 	tg->dev = dev;
2953 
2954 	mutex_lock(&dev->mode_config.idr_mutex);
2955 	ret = idr_alloc(&dev->mode_config.tile_idr, tg, 1, 0, GFP_KERNEL);
2956 	if (ret >= 0) {
2957 		tg->id = ret;
2958 	} else {
2959 		kfree(tg);
2960 		tg = NULL;
2961 	}
2962 
2963 	mutex_unlock(&dev->mode_config.idr_mutex);
2964 	return tg;
2965 }
2966 EXPORT_SYMBOL(drm_mode_create_tile_group);
2967