xref: /openbmc/linux/drivers/gpu/drm/drm_connector.c (revision 2b77dcc5)
1 /*
2  * Copyright (c) 2016 Intel Corporation
3  *
4  * Permission to use, copy, modify, distribute, and sell this software and its
5  * documentation for any purpose is hereby granted without fee, provided that
6  * the above copyright notice appear in all copies and that both that copyright
7  * notice and this permission notice appear in supporting documentation, and
8  * that the name of the copyright holders not be used in advertising or
9  * publicity pertaining to distribution of the software without specific,
10  * written prior permission.  The copyright holders make no representations
11  * about the suitability of this software for any purpose.  It is provided "as
12  * is" without express or implied warranty.
13  *
14  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20  * OF THIS SOFTWARE.
21  */
22 
23 #include <drm/drm_connector.h>
24 #include <drm/drm_edid.h>
25 #include <drm/drm_encoder.h>
26 #include <drm/drm_utils.h>
27 #include <drm/drm_print.h>
28 #include <drm/drm_drv.h>
29 #include <drm/drm_file.h>
30 
31 #include <linux/uaccess.h>
32 
33 #include "drm_crtc_internal.h"
34 #include "drm_internal.h"
35 
36 /**
37  * DOC: overview
38  *
39  * In DRM connectors are the general abstraction for display sinks, and include
40  * als fixed panels or anything else that can display pixels in some form. As
41  * opposed to all other KMS objects representing hardware (like CRTC, encoder or
42  * plane abstractions) connectors can be hotplugged and unplugged at runtime.
43  * Hence they are reference-counted using drm_connector_get() and
44  * drm_connector_put().
45  *
46  * KMS driver must create, initialize, register and attach at a &struct
47  * drm_connector for each such sink. The instance is created as other KMS
48  * objects and initialized by setting the following fields. The connector is
49  * initialized with a call to drm_connector_init() with a pointer to the
50  * &struct drm_connector_funcs and a connector type, and then exposed to
51  * userspace with a call to drm_connector_register().
52  *
53  * Connectors must be attached to an encoder to be used. For devices that map
54  * connectors to encoders 1:1, the connector should be attached at
55  * initialization time with a call to drm_connector_attach_encoder(). The
56  * driver must also set the &drm_connector.encoder field to point to the
57  * attached encoder.
58  *
59  * For connectors which are not fixed (like built-in panels) the driver needs to
60  * support hotplug notifications. The simplest way to do that is by using the
61  * probe helpers, see drm_kms_helper_poll_init() for connectors which don't have
62  * hardware support for hotplug interrupts. Connectors with hardware hotplug
63  * support can instead use e.g. drm_helper_hpd_irq_event().
64  */
65 
66 struct drm_conn_prop_enum_list {
67 	int type;
68 	const char *name;
69 	struct ida ida;
70 };
71 
72 /*
73  * Connector and encoder types.
74  */
75 static struct drm_conn_prop_enum_list drm_connector_enum_list[] = {
76 	{ DRM_MODE_CONNECTOR_Unknown, "Unknown" },
77 	{ DRM_MODE_CONNECTOR_VGA, "VGA" },
78 	{ DRM_MODE_CONNECTOR_DVII, "DVI-I" },
79 	{ DRM_MODE_CONNECTOR_DVID, "DVI-D" },
80 	{ DRM_MODE_CONNECTOR_DVIA, "DVI-A" },
81 	{ DRM_MODE_CONNECTOR_Composite, "Composite" },
82 	{ DRM_MODE_CONNECTOR_SVIDEO, "SVIDEO" },
83 	{ DRM_MODE_CONNECTOR_LVDS, "LVDS" },
84 	{ DRM_MODE_CONNECTOR_Component, "Component" },
85 	{ DRM_MODE_CONNECTOR_9PinDIN, "DIN" },
86 	{ DRM_MODE_CONNECTOR_DisplayPort, "DP" },
87 	{ DRM_MODE_CONNECTOR_HDMIA, "HDMI-A" },
88 	{ DRM_MODE_CONNECTOR_HDMIB, "HDMI-B" },
89 	{ DRM_MODE_CONNECTOR_TV, "TV" },
90 	{ DRM_MODE_CONNECTOR_eDP, "eDP" },
91 	{ DRM_MODE_CONNECTOR_VIRTUAL, "Virtual" },
92 	{ DRM_MODE_CONNECTOR_DSI, "DSI" },
93 	{ DRM_MODE_CONNECTOR_DPI, "DPI" },
94 	{ DRM_MODE_CONNECTOR_WRITEBACK, "Writeback" },
95 	{ DRM_MODE_CONNECTOR_SPI, "SPI" },
96 };
97 
98 void drm_connector_ida_init(void)
99 {
100 	int i;
101 
102 	for (i = 0; i < ARRAY_SIZE(drm_connector_enum_list); i++)
103 		ida_init(&drm_connector_enum_list[i].ida);
104 }
105 
106 void drm_connector_ida_destroy(void)
107 {
108 	int i;
109 
110 	for (i = 0; i < ARRAY_SIZE(drm_connector_enum_list); i++)
111 		ida_destroy(&drm_connector_enum_list[i].ida);
112 }
113 
114 /**
115  * drm_connector_get_cmdline_mode - reads the user's cmdline mode
116  * @connector: connector to quwery
117  *
118  * The kernel supports per-connector configuration of its consoles through
119  * use of the video= parameter. This function parses that option and
120  * extracts the user's specified mode (or enable/disable status) for a
121  * particular connector. This is typically only used during the early fbdev
122  * setup.
123  */
124 static void drm_connector_get_cmdline_mode(struct drm_connector *connector)
125 {
126 	struct drm_cmdline_mode *mode = &connector->cmdline_mode;
127 	char *option = NULL;
128 
129 	if (fb_get_options(connector->name, &option))
130 		return;
131 
132 	if (!drm_mode_parse_command_line_for_connector(option,
133 						       connector,
134 						       mode))
135 		return;
136 
137 	if (mode->force) {
138 		DRM_INFO("forcing %s connector %s\n", connector->name,
139 			 drm_get_connector_force_name(mode->force));
140 		connector->force = mode->force;
141 	}
142 
143 	DRM_DEBUG_KMS("cmdline mode for connector %s %s %dx%d@%dHz%s%s%s\n",
144 		      connector->name, mode->name,
145 		      mode->xres, mode->yres,
146 		      mode->refresh_specified ? mode->refresh : 60,
147 		      mode->rb ? " reduced blanking" : "",
148 		      mode->margins ? " with margins" : "",
149 		      mode->interlace ?  " interlaced" : "");
150 }
151 
152 static void drm_connector_free(struct kref *kref)
153 {
154 	struct drm_connector *connector =
155 		container_of(kref, struct drm_connector, base.refcount);
156 	struct drm_device *dev = connector->dev;
157 
158 	drm_mode_object_unregister(dev, &connector->base);
159 	connector->funcs->destroy(connector);
160 }
161 
162 void drm_connector_free_work_fn(struct work_struct *work)
163 {
164 	struct drm_connector *connector, *n;
165 	struct drm_device *dev =
166 		container_of(work, struct drm_device, mode_config.connector_free_work);
167 	struct drm_mode_config *config = &dev->mode_config;
168 	unsigned long flags;
169 	struct llist_node *freed;
170 
171 	spin_lock_irqsave(&config->connector_list_lock, flags);
172 	freed = llist_del_all(&config->connector_free_list);
173 	spin_unlock_irqrestore(&config->connector_list_lock, flags);
174 
175 	llist_for_each_entry_safe(connector, n, freed, free_node) {
176 		drm_mode_object_unregister(dev, &connector->base);
177 		connector->funcs->destroy(connector);
178 	}
179 }
180 
181 /**
182  * drm_connector_init - Init a preallocated connector
183  * @dev: DRM device
184  * @connector: the connector to init
185  * @funcs: callbacks for this connector
186  * @connector_type: user visible type of the connector
187  *
188  * Initialises a preallocated connector. Connectors should be
189  * subclassed as part of driver connector objects.
190  *
191  * Returns:
192  * Zero on success, error code on failure.
193  */
194 int drm_connector_init(struct drm_device *dev,
195 		       struct drm_connector *connector,
196 		       const struct drm_connector_funcs *funcs,
197 		       int connector_type)
198 {
199 	struct drm_mode_config *config = &dev->mode_config;
200 	int ret;
201 	struct ida *connector_ida =
202 		&drm_connector_enum_list[connector_type].ida;
203 
204 	WARN_ON(drm_drv_uses_atomic_modeset(dev) &&
205 		(!funcs->atomic_destroy_state ||
206 		 !funcs->atomic_duplicate_state));
207 
208 	ret = __drm_mode_object_add(dev, &connector->base,
209 				    DRM_MODE_OBJECT_CONNECTOR,
210 				    false, drm_connector_free);
211 	if (ret)
212 		return ret;
213 
214 	connector->base.properties = &connector->properties;
215 	connector->dev = dev;
216 	connector->funcs = funcs;
217 
218 	/* connector index is used with 32bit bitmasks */
219 	ret = ida_simple_get(&config->connector_ida, 0, 32, GFP_KERNEL);
220 	if (ret < 0) {
221 		DRM_DEBUG_KMS("Failed to allocate %s connector index: %d\n",
222 			      drm_connector_enum_list[connector_type].name,
223 			      ret);
224 		goto out_put;
225 	}
226 	connector->index = ret;
227 	ret = 0;
228 
229 	connector->connector_type = connector_type;
230 	connector->connector_type_id =
231 		ida_simple_get(connector_ida, 1, 0, GFP_KERNEL);
232 	if (connector->connector_type_id < 0) {
233 		ret = connector->connector_type_id;
234 		goto out_put_id;
235 	}
236 	connector->name =
237 		kasprintf(GFP_KERNEL, "%s-%d",
238 			  drm_connector_enum_list[connector_type].name,
239 			  connector->connector_type_id);
240 	if (!connector->name) {
241 		ret = -ENOMEM;
242 		goto out_put_type_id;
243 	}
244 
245 	INIT_LIST_HEAD(&connector->probed_modes);
246 	INIT_LIST_HEAD(&connector->modes);
247 	mutex_init(&connector->mutex);
248 	connector->edid_blob_ptr = NULL;
249 	connector->tile_blob_ptr = NULL;
250 	connector->status = connector_status_unknown;
251 	connector->display_info.panel_orientation =
252 		DRM_MODE_PANEL_ORIENTATION_UNKNOWN;
253 
254 	drm_connector_get_cmdline_mode(connector);
255 
256 	/* We should add connectors at the end to avoid upsetting the connector
257 	 * index too much. */
258 	spin_lock_irq(&config->connector_list_lock);
259 	list_add_tail(&connector->head, &config->connector_list);
260 	config->num_connector++;
261 	spin_unlock_irq(&config->connector_list_lock);
262 
263 	if (connector_type != DRM_MODE_CONNECTOR_VIRTUAL &&
264 	    connector_type != DRM_MODE_CONNECTOR_WRITEBACK)
265 		drm_connector_attach_edid_property(connector);
266 
267 	drm_object_attach_property(&connector->base,
268 				      config->dpms_property, 0);
269 
270 	drm_object_attach_property(&connector->base,
271 				   config->link_status_property,
272 				   0);
273 
274 	drm_object_attach_property(&connector->base,
275 				   config->non_desktop_property,
276 				   0);
277 	drm_object_attach_property(&connector->base,
278 				   config->tile_property,
279 				   0);
280 
281 	if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
282 		drm_object_attach_property(&connector->base, config->prop_crtc_id, 0);
283 	}
284 
285 	connector->debugfs_entry = NULL;
286 out_put_type_id:
287 	if (ret)
288 		ida_simple_remove(connector_ida, connector->connector_type_id);
289 out_put_id:
290 	if (ret)
291 		ida_simple_remove(&config->connector_ida, connector->index);
292 out_put:
293 	if (ret)
294 		drm_mode_object_unregister(dev, &connector->base);
295 
296 	return ret;
297 }
298 EXPORT_SYMBOL(drm_connector_init);
299 
300 /**
301  * drm_connector_init_with_ddc - Init a preallocated connector
302  * @dev: DRM device
303  * @connector: the connector to init
304  * @funcs: callbacks for this connector
305  * @connector_type: user visible type of the connector
306  * @ddc: pointer to the associated ddc adapter
307  *
308  * Initialises a preallocated connector. Connectors should be
309  * subclassed as part of driver connector objects.
310  *
311  * Ensures that the ddc field of the connector is correctly set.
312  *
313  * Returns:
314  * Zero on success, error code on failure.
315  */
316 int drm_connector_init_with_ddc(struct drm_device *dev,
317 				struct drm_connector *connector,
318 				const struct drm_connector_funcs *funcs,
319 				int connector_type,
320 				struct i2c_adapter *ddc)
321 {
322 	int ret;
323 
324 	ret = drm_connector_init(dev, connector, funcs, connector_type);
325 	if (ret)
326 		return ret;
327 
328 	/* provide ddc symlink in sysfs */
329 	connector->ddc = ddc;
330 
331 	return ret;
332 }
333 EXPORT_SYMBOL(drm_connector_init_with_ddc);
334 
335 /**
336  * drm_connector_attach_edid_property - attach edid property.
337  * @connector: the connector
338  *
339  * Some connector types like DRM_MODE_CONNECTOR_VIRTUAL do not get a
340  * edid property attached by default.  This function can be used to
341  * explicitly enable the edid property in these cases.
342  */
343 void drm_connector_attach_edid_property(struct drm_connector *connector)
344 {
345 	struct drm_mode_config *config = &connector->dev->mode_config;
346 
347 	drm_object_attach_property(&connector->base,
348 				   config->edid_property,
349 				   0);
350 }
351 EXPORT_SYMBOL(drm_connector_attach_edid_property);
352 
353 /**
354  * drm_connector_attach_encoder - attach a connector to an encoder
355  * @connector: connector to attach
356  * @encoder: encoder to attach @connector to
357  *
358  * This function links up a connector to an encoder. Note that the routing
359  * restrictions between encoders and crtcs are exposed to userspace through the
360  * possible_clones and possible_crtcs bitmasks.
361  *
362  * Returns:
363  * Zero on success, negative errno on failure.
364  */
365 int drm_connector_attach_encoder(struct drm_connector *connector,
366 				 struct drm_encoder *encoder)
367 {
368 	/*
369 	 * In the past, drivers have attempted to model the static association
370 	 * of connector to encoder in simple connector/encoder devices using a
371 	 * direct assignment of connector->encoder = encoder. This connection
372 	 * is a logical one and the responsibility of the core, so drivers are
373 	 * expected not to mess with this.
374 	 *
375 	 * Note that the error return should've been enough here, but a large
376 	 * majority of drivers ignores the return value, so add in a big WARN
377 	 * to get people's attention.
378 	 */
379 	if (WARN_ON(connector->encoder))
380 		return -EINVAL;
381 
382 	connector->possible_encoders |= drm_encoder_mask(encoder);
383 
384 	return 0;
385 }
386 EXPORT_SYMBOL(drm_connector_attach_encoder);
387 
388 /**
389  * drm_connector_has_possible_encoder - check if the connector and encoder are
390  * associated with each other
391  * @connector: the connector
392  * @encoder: the encoder
393  *
394  * Returns:
395  * True if @encoder is one of the possible encoders for @connector.
396  */
397 bool drm_connector_has_possible_encoder(struct drm_connector *connector,
398 					struct drm_encoder *encoder)
399 {
400 	return connector->possible_encoders & drm_encoder_mask(encoder);
401 }
402 EXPORT_SYMBOL(drm_connector_has_possible_encoder);
403 
404 static void drm_mode_remove(struct drm_connector *connector,
405 			    struct drm_display_mode *mode)
406 {
407 	list_del(&mode->head);
408 	drm_mode_destroy(connector->dev, mode);
409 }
410 
411 /**
412  * drm_connector_cleanup - cleans up an initialised connector
413  * @connector: connector to cleanup
414  *
415  * Cleans up the connector but doesn't free the object.
416  */
417 void drm_connector_cleanup(struct drm_connector *connector)
418 {
419 	struct drm_device *dev = connector->dev;
420 	struct drm_display_mode *mode, *t;
421 
422 	/* The connector should have been removed from userspace long before
423 	 * it is finally destroyed.
424 	 */
425 	if (WARN_ON(connector->registration_state ==
426 		    DRM_CONNECTOR_REGISTERED))
427 		drm_connector_unregister(connector);
428 
429 	if (connector->tile_group) {
430 		drm_mode_put_tile_group(dev, connector->tile_group);
431 		connector->tile_group = NULL;
432 	}
433 
434 	list_for_each_entry_safe(mode, t, &connector->probed_modes, head)
435 		drm_mode_remove(connector, mode);
436 
437 	list_for_each_entry_safe(mode, t, &connector->modes, head)
438 		drm_mode_remove(connector, mode);
439 
440 	ida_simple_remove(&drm_connector_enum_list[connector->connector_type].ida,
441 			  connector->connector_type_id);
442 
443 	ida_simple_remove(&dev->mode_config.connector_ida,
444 			  connector->index);
445 
446 	kfree(connector->display_info.bus_formats);
447 	drm_mode_object_unregister(dev, &connector->base);
448 	kfree(connector->name);
449 	connector->name = NULL;
450 	spin_lock_irq(&dev->mode_config.connector_list_lock);
451 	list_del(&connector->head);
452 	dev->mode_config.num_connector--;
453 	spin_unlock_irq(&dev->mode_config.connector_list_lock);
454 
455 	WARN_ON(connector->state && !connector->funcs->atomic_destroy_state);
456 	if (connector->state && connector->funcs->atomic_destroy_state)
457 		connector->funcs->atomic_destroy_state(connector,
458 						       connector->state);
459 
460 	mutex_destroy(&connector->mutex);
461 
462 	memset(connector, 0, sizeof(*connector));
463 }
464 EXPORT_SYMBOL(drm_connector_cleanup);
465 
466 /**
467  * drm_connector_register - register a connector
468  * @connector: the connector to register
469  *
470  * Register userspace interfaces for a connector. Only call this for connectors
471  * which can be hotplugged after drm_dev_register() has been called already,
472  * e.g. DP MST connectors. All other connectors will be registered automatically
473  * when calling drm_dev_register().
474  *
475  * Returns:
476  * Zero on success, error code on failure.
477  */
478 int drm_connector_register(struct drm_connector *connector)
479 {
480 	int ret = 0;
481 
482 	if (!connector->dev->registered)
483 		return 0;
484 
485 	mutex_lock(&connector->mutex);
486 	if (connector->registration_state != DRM_CONNECTOR_INITIALIZING)
487 		goto unlock;
488 
489 	ret = drm_sysfs_connector_add(connector);
490 	if (ret)
491 		goto unlock;
492 
493 	drm_debugfs_connector_add(connector);
494 
495 	if (connector->funcs->late_register) {
496 		ret = connector->funcs->late_register(connector);
497 		if (ret)
498 			goto err_debugfs;
499 	}
500 
501 	drm_mode_object_register(connector->dev, &connector->base);
502 
503 	connector->registration_state = DRM_CONNECTOR_REGISTERED;
504 	goto unlock;
505 
506 err_debugfs:
507 	drm_debugfs_connector_remove(connector);
508 	drm_sysfs_connector_remove(connector);
509 unlock:
510 	mutex_unlock(&connector->mutex);
511 	return ret;
512 }
513 EXPORT_SYMBOL(drm_connector_register);
514 
515 /**
516  * drm_connector_unregister - unregister a connector
517  * @connector: the connector to unregister
518  *
519  * Unregister userspace interfaces for a connector. Only call this for
520  * connectors which have registered explicitly by calling drm_dev_register(),
521  * since connectors are unregistered automatically when drm_dev_unregister() is
522  * called.
523  */
524 void drm_connector_unregister(struct drm_connector *connector)
525 {
526 	mutex_lock(&connector->mutex);
527 	if (connector->registration_state != DRM_CONNECTOR_REGISTERED) {
528 		mutex_unlock(&connector->mutex);
529 		return;
530 	}
531 
532 	if (connector->funcs->early_unregister)
533 		connector->funcs->early_unregister(connector);
534 
535 	drm_sysfs_connector_remove(connector);
536 	drm_debugfs_connector_remove(connector);
537 
538 	connector->registration_state = DRM_CONNECTOR_UNREGISTERED;
539 	mutex_unlock(&connector->mutex);
540 }
541 EXPORT_SYMBOL(drm_connector_unregister);
542 
543 void drm_connector_unregister_all(struct drm_device *dev)
544 {
545 	struct drm_connector *connector;
546 	struct drm_connector_list_iter conn_iter;
547 
548 	drm_connector_list_iter_begin(dev, &conn_iter);
549 	drm_for_each_connector_iter(connector, &conn_iter)
550 		drm_connector_unregister(connector);
551 	drm_connector_list_iter_end(&conn_iter);
552 }
553 
554 int drm_connector_register_all(struct drm_device *dev)
555 {
556 	struct drm_connector *connector;
557 	struct drm_connector_list_iter conn_iter;
558 	int ret = 0;
559 
560 	drm_connector_list_iter_begin(dev, &conn_iter);
561 	drm_for_each_connector_iter(connector, &conn_iter) {
562 		ret = drm_connector_register(connector);
563 		if (ret)
564 			break;
565 	}
566 	drm_connector_list_iter_end(&conn_iter);
567 
568 	if (ret)
569 		drm_connector_unregister_all(dev);
570 	return ret;
571 }
572 
573 /**
574  * drm_get_connector_status_name - return a string for connector status
575  * @status: connector status to compute name of
576  *
577  * In contrast to the other drm_get_*_name functions this one here returns a
578  * const pointer and hence is threadsafe.
579  */
580 const char *drm_get_connector_status_name(enum drm_connector_status status)
581 {
582 	if (status == connector_status_connected)
583 		return "connected";
584 	else if (status == connector_status_disconnected)
585 		return "disconnected";
586 	else
587 		return "unknown";
588 }
589 EXPORT_SYMBOL(drm_get_connector_status_name);
590 
591 /**
592  * drm_get_connector_force_name - return a string for connector force
593  * @force: connector force to get name of
594  *
595  * Returns: const pointer to name.
596  */
597 const char *drm_get_connector_force_name(enum drm_connector_force force)
598 {
599 	switch (force) {
600 	case DRM_FORCE_UNSPECIFIED:
601 		return "unspecified";
602 	case DRM_FORCE_OFF:
603 		return "off";
604 	case DRM_FORCE_ON:
605 		return "on";
606 	case DRM_FORCE_ON_DIGITAL:
607 		return "digital";
608 	default:
609 		return "unknown";
610 	}
611 }
612 
613 #ifdef CONFIG_LOCKDEP
614 static struct lockdep_map connector_list_iter_dep_map = {
615 	.name = "drm_connector_list_iter"
616 };
617 #endif
618 
619 /**
620  * drm_connector_list_iter_begin - initialize a connector_list iterator
621  * @dev: DRM device
622  * @iter: connector_list iterator
623  *
624  * Sets @iter up to walk the &drm_mode_config.connector_list of @dev. @iter
625  * must always be cleaned up again by calling drm_connector_list_iter_end().
626  * Iteration itself happens using drm_connector_list_iter_next() or
627  * drm_for_each_connector_iter().
628  */
629 void drm_connector_list_iter_begin(struct drm_device *dev,
630 				   struct drm_connector_list_iter *iter)
631 {
632 	iter->dev = dev;
633 	iter->conn = NULL;
634 	lock_acquire_shared_recursive(&connector_list_iter_dep_map, 0, 1, NULL, _RET_IP_);
635 }
636 EXPORT_SYMBOL(drm_connector_list_iter_begin);
637 
638 /*
639  * Extra-safe connector put function that works in any context. Should only be
640  * used from the connector_iter functions, where we never really expect to
641  * actually release the connector when dropping our final reference.
642  */
643 static void
644 __drm_connector_put_safe(struct drm_connector *conn)
645 {
646 	struct drm_mode_config *config = &conn->dev->mode_config;
647 
648 	lockdep_assert_held(&config->connector_list_lock);
649 
650 	if (!refcount_dec_and_test(&conn->base.refcount.refcount))
651 		return;
652 
653 	llist_add(&conn->free_node, &config->connector_free_list);
654 	schedule_work(&config->connector_free_work);
655 }
656 
657 /**
658  * drm_connector_list_iter_next - return next connector
659  * @iter: connector_list iterator
660  *
661  * Returns the next connector for @iter, or NULL when the list walk has
662  * completed.
663  */
664 struct drm_connector *
665 drm_connector_list_iter_next(struct drm_connector_list_iter *iter)
666 {
667 	struct drm_connector *old_conn = iter->conn;
668 	struct drm_mode_config *config = &iter->dev->mode_config;
669 	struct list_head *lhead;
670 	unsigned long flags;
671 
672 	spin_lock_irqsave(&config->connector_list_lock, flags);
673 	lhead = old_conn ? &old_conn->head : &config->connector_list;
674 
675 	do {
676 		if (lhead->next == &config->connector_list) {
677 			iter->conn = NULL;
678 			break;
679 		}
680 
681 		lhead = lhead->next;
682 		iter->conn = list_entry(lhead, struct drm_connector, head);
683 
684 		/* loop until it's not a zombie connector */
685 	} while (!kref_get_unless_zero(&iter->conn->base.refcount));
686 
687 	if (old_conn)
688 		__drm_connector_put_safe(old_conn);
689 	spin_unlock_irqrestore(&config->connector_list_lock, flags);
690 
691 	return iter->conn;
692 }
693 EXPORT_SYMBOL(drm_connector_list_iter_next);
694 
695 /**
696  * drm_connector_list_iter_end - tear down a connector_list iterator
697  * @iter: connector_list iterator
698  *
699  * Tears down @iter and releases any resources (like &drm_connector references)
700  * acquired while walking the list. This must always be called, both when the
701  * iteration completes fully or when it was aborted without walking the entire
702  * list.
703  */
704 void drm_connector_list_iter_end(struct drm_connector_list_iter *iter)
705 {
706 	struct drm_mode_config *config = &iter->dev->mode_config;
707 	unsigned long flags;
708 
709 	iter->dev = NULL;
710 	if (iter->conn) {
711 		spin_lock_irqsave(&config->connector_list_lock, flags);
712 		__drm_connector_put_safe(iter->conn);
713 		spin_unlock_irqrestore(&config->connector_list_lock, flags);
714 	}
715 	lock_release(&connector_list_iter_dep_map, 0, _RET_IP_);
716 }
717 EXPORT_SYMBOL(drm_connector_list_iter_end);
718 
719 static const struct drm_prop_enum_list drm_subpixel_enum_list[] = {
720 	{ SubPixelUnknown, "Unknown" },
721 	{ SubPixelHorizontalRGB, "Horizontal RGB" },
722 	{ SubPixelHorizontalBGR, "Horizontal BGR" },
723 	{ SubPixelVerticalRGB, "Vertical RGB" },
724 	{ SubPixelVerticalBGR, "Vertical BGR" },
725 	{ SubPixelNone, "None" },
726 };
727 
728 /**
729  * drm_get_subpixel_order_name - return a string for a given subpixel enum
730  * @order: enum of subpixel_order
731  *
732  * Note you could abuse this and return something out of bounds, but that
733  * would be a caller error.  No unscrubbed user data should make it here.
734  */
735 const char *drm_get_subpixel_order_name(enum subpixel_order order)
736 {
737 	return drm_subpixel_enum_list[order].name;
738 }
739 EXPORT_SYMBOL(drm_get_subpixel_order_name);
740 
741 static const struct drm_prop_enum_list drm_dpms_enum_list[] = {
742 	{ DRM_MODE_DPMS_ON, "On" },
743 	{ DRM_MODE_DPMS_STANDBY, "Standby" },
744 	{ DRM_MODE_DPMS_SUSPEND, "Suspend" },
745 	{ DRM_MODE_DPMS_OFF, "Off" }
746 };
747 DRM_ENUM_NAME_FN(drm_get_dpms_name, drm_dpms_enum_list)
748 
749 static const struct drm_prop_enum_list drm_link_status_enum_list[] = {
750 	{ DRM_MODE_LINK_STATUS_GOOD, "Good" },
751 	{ DRM_MODE_LINK_STATUS_BAD, "Bad" },
752 };
753 
754 /**
755  * drm_display_info_set_bus_formats - set the supported bus formats
756  * @info: display info to store bus formats in
757  * @formats: array containing the supported bus formats
758  * @num_formats: the number of entries in the fmts array
759  *
760  * Store the supported bus formats in display info structure.
761  * See MEDIA_BUS_FMT_* definitions in include/uapi/linux/media-bus-format.h for
762  * a full list of available formats.
763  */
764 int drm_display_info_set_bus_formats(struct drm_display_info *info,
765 				     const u32 *formats,
766 				     unsigned int num_formats)
767 {
768 	u32 *fmts = NULL;
769 
770 	if (!formats && num_formats)
771 		return -EINVAL;
772 
773 	if (formats && num_formats) {
774 		fmts = kmemdup(formats, sizeof(*formats) * num_formats,
775 			       GFP_KERNEL);
776 		if (!fmts)
777 			return -ENOMEM;
778 	}
779 
780 	kfree(info->bus_formats);
781 	info->bus_formats = fmts;
782 	info->num_bus_formats = num_formats;
783 
784 	return 0;
785 }
786 EXPORT_SYMBOL(drm_display_info_set_bus_formats);
787 
788 /* Optional connector properties. */
789 static const struct drm_prop_enum_list drm_scaling_mode_enum_list[] = {
790 	{ DRM_MODE_SCALE_NONE, "None" },
791 	{ DRM_MODE_SCALE_FULLSCREEN, "Full" },
792 	{ DRM_MODE_SCALE_CENTER, "Center" },
793 	{ DRM_MODE_SCALE_ASPECT, "Full aspect" },
794 };
795 
796 static const struct drm_prop_enum_list drm_aspect_ratio_enum_list[] = {
797 	{ DRM_MODE_PICTURE_ASPECT_NONE, "Automatic" },
798 	{ DRM_MODE_PICTURE_ASPECT_4_3, "4:3" },
799 	{ DRM_MODE_PICTURE_ASPECT_16_9, "16:9" },
800 };
801 
802 static const struct drm_prop_enum_list drm_content_type_enum_list[] = {
803 	{ DRM_MODE_CONTENT_TYPE_NO_DATA, "No Data" },
804 	{ DRM_MODE_CONTENT_TYPE_GRAPHICS, "Graphics" },
805 	{ DRM_MODE_CONTENT_TYPE_PHOTO, "Photo" },
806 	{ DRM_MODE_CONTENT_TYPE_CINEMA, "Cinema" },
807 	{ DRM_MODE_CONTENT_TYPE_GAME, "Game" },
808 };
809 
810 static const struct drm_prop_enum_list drm_panel_orientation_enum_list[] = {
811 	{ DRM_MODE_PANEL_ORIENTATION_NORMAL,	"Normal"	},
812 	{ DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP,	"Upside Down"	},
813 	{ DRM_MODE_PANEL_ORIENTATION_LEFT_UP,	"Left Side Up"	},
814 	{ DRM_MODE_PANEL_ORIENTATION_RIGHT_UP,	"Right Side Up"	},
815 };
816 
817 static const struct drm_prop_enum_list drm_dvi_i_select_enum_list[] = {
818 	{ DRM_MODE_SUBCONNECTOR_Automatic, "Automatic" }, /* DVI-I and TV-out */
819 	{ DRM_MODE_SUBCONNECTOR_DVID,      "DVI-D"     }, /* DVI-I  */
820 	{ DRM_MODE_SUBCONNECTOR_DVIA,      "DVI-A"     }, /* DVI-I  */
821 };
822 DRM_ENUM_NAME_FN(drm_get_dvi_i_select_name, drm_dvi_i_select_enum_list)
823 
824 static const struct drm_prop_enum_list drm_dvi_i_subconnector_enum_list[] = {
825 	{ DRM_MODE_SUBCONNECTOR_Unknown,   "Unknown"   }, /* DVI-I and TV-out */
826 	{ DRM_MODE_SUBCONNECTOR_DVID,      "DVI-D"     }, /* DVI-I  */
827 	{ DRM_MODE_SUBCONNECTOR_DVIA,      "DVI-A"     }, /* DVI-I  */
828 };
829 DRM_ENUM_NAME_FN(drm_get_dvi_i_subconnector_name,
830 		 drm_dvi_i_subconnector_enum_list)
831 
832 static const struct drm_prop_enum_list drm_tv_select_enum_list[] = {
833 	{ DRM_MODE_SUBCONNECTOR_Automatic, "Automatic" }, /* DVI-I and TV-out */
834 	{ DRM_MODE_SUBCONNECTOR_Composite, "Composite" }, /* TV-out */
835 	{ DRM_MODE_SUBCONNECTOR_SVIDEO,    "SVIDEO"    }, /* TV-out */
836 	{ DRM_MODE_SUBCONNECTOR_Component, "Component" }, /* TV-out */
837 	{ DRM_MODE_SUBCONNECTOR_SCART,     "SCART"     }, /* TV-out */
838 };
839 DRM_ENUM_NAME_FN(drm_get_tv_select_name, drm_tv_select_enum_list)
840 
841 static const struct drm_prop_enum_list drm_tv_subconnector_enum_list[] = {
842 	{ DRM_MODE_SUBCONNECTOR_Unknown,   "Unknown"   }, /* DVI-I and TV-out */
843 	{ DRM_MODE_SUBCONNECTOR_Composite, "Composite" }, /* TV-out */
844 	{ DRM_MODE_SUBCONNECTOR_SVIDEO,    "SVIDEO"    }, /* TV-out */
845 	{ DRM_MODE_SUBCONNECTOR_Component, "Component" }, /* TV-out */
846 	{ DRM_MODE_SUBCONNECTOR_SCART,     "SCART"     }, /* TV-out */
847 };
848 DRM_ENUM_NAME_FN(drm_get_tv_subconnector_name,
849 		 drm_tv_subconnector_enum_list)
850 
851 static const struct drm_prop_enum_list hdmi_colorspaces[] = {
852 	/* For Default case, driver will set the colorspace */
853 	{ DRM_MODE_COLORIMETRY_DEFAULT, "Default" },
854 	/* Standard Definition Colorimetry based on CEA 861 */
855 	{ DRM_MODE_COLORIMETRY_SMPTE_170M_YCC, "SMPTE_170M_YCC" },
856 	{ DRM_MODE_COLORIMETRY_BT709_YCC, "BT709_YCC" },
857 	/* Standard Definition Colorimetry based on IEC 61966-2-4 */
858 	{ DRM_MODE_COLORIMETRY_XVYCC_601, "XVYCC_601" },
859 	/* High Definition Colorimetry based on IEC 61966-2-4 */
860 	{ DRM_MODE_COLORIMETRY_XVYCC_709, "XVYCC_709" },
861 	/* Colorimetry based on IEC 61966-2-1/Amendment 1 */
862 	{ DRM_MODE_COLORIMETRY_SYCC_601, "SYCC_601" },
863 	/* Colorimetry based on IEC 61966-2-5 [33] */
864 	{ DRM_MODE_COLORIMETRY_OPYCC_601, "opYCC_601" },
865 	/* Colorimetry based on IEC 61966-2-5 */
866 	{ DRM_MODE_COLORIMETRY_OPRGB, "opRGB" },
867 	/* Colorimetry based on ITU-R BT.2020 */
868 	{ DRM_MODE_COLORIMETRY_BT2020_CYCC, "BT2020_CYCC" },
869 	/* Colorimetry based on ITU-R BT.2020 */
870 	{ DRM_MODE_COLORIMETRY_BT2020_RGB, "BT2020_RGB" },
871 	/* Colorimetry based on ITU-R BT.2020 */
872 	{ DRM_MODE_COLORIMETRY_BT2020_YCC, "BT2020_YCC" },
873 	/* Added as part of Additional Colorimetry Extension in 861.G */
874 	{ DRM_MODE_COLORIMETRY_DCI_P3_RGB_D65, "DCI-P3_RGB_D65" },
875 	{ DRM_MODE_COLORIMETRY_DCI_P3_RGB_THEATER, "DCI-P3_RGB_Theater" },
876 };
877 
878 /*
879  * As per DP 1.4a spec, 2.2.5.7.5 VSC SDP Payload for Pixel Encoding/Colorimetry
880  * Format Table 2-120
881  */
882 static const struct drm_prop_enum_list dp_colorspaces[] = {
883 	/* For Default case, driver will set the colorspace */
884 	{ DRM_MODE_COLORIMETRY_DEFAULT, "Default" },
885 	{ DRM_MODE_COLORIMETRY_RGB_WIDE_FIXED, "RGB_Wide_Gamut_Fixed_Point" },
886 	/* Colorimetry based on scRGB (IEC 61966-2-2) */
887 	{ DRM_MODE_COLORIMETRY_RGB_WIDE_FLOAT, "RGB_Wide_Gamut_Floating_Point" },
888 	/* Colorimetry based on IEC 61966-2-5 */
889 	{ DRM_MODE_COLORIMETRY_OPRGB, "opRGB" },
890 	/* Colorimetry based on SMPTE RP 431-2 */
891 	{ DRM_MODE_COLORIMETRY_DCI_P3_RGB_D65, "DCI-P3_RGB_D65" },
892 	/* Colorimetry based on ITU-R BT.2020 */
893 	{ DRM_MODE_COLORIMETRY_BT2020_RGB, "BT2020_RGB" },
894 	{ DRM_MODE_COLORIMETRY_BT601_YCC, "BT601_YCC" },
895 	{ DRM_MODE_COLORIMETRY_BT709_YCC, "BT709_YCC" },
896 	/* Standard Definition Colorimetry based on IEC 61966-2-4 */
897 	{ DRM_MODE_COLORIMETRY_XVYCC_601, "XVYCC_601" },
898 	/* High Definition Colorimetry based on IEC 61966-2-4 */
899 	{ DRM_MODE_COLORIMETRY_XVYCC_709, "XVYCC_709" },
900 	/* Colorimetry based on IEC 61966-2-1/Amendment 1 */
901 	{ DRM_MODE_COLORIMETRY_SYCC_601, "SYCC_601" },
902 	/* Colorimetry based on IEC 61966-2-5 [33] */
903 	{ DRM_MODE_COLORIMETRY_OPYCC_601, "opYCC_601" },
904 	/* Colorimetry based on ITU-R BT.2020 */
905 	{ DRM_MODE_COLORIMETRY_BT2020_CYCC, "BT2020_CYCC" },
906 	/* Colorimetry based on ITU-R BT.2020 */
907 	{ DRM_MODE_COLORIMETRY_BT2020_YCC, "BT2020_YCC" },
908 };
909 
910 /**
911  * DOC: standard connector properties
912  *
913  * DRM connectors have a few standardized properties:
914  *
915  * EDID:
916  * 	Blob property which contains the current EDID read from the sink. This
917  * 	is useful to parse sink identification information like vendor, model
918  * 	and serial. Drivers should update this property by calling
919  * 	drm_connector_update_edid_property(), usually after having parsed
920  * 	the EDID using drm_add_edid_modes(). Userspace cannot change this
921  * 	property.
922  * DPMS:
923  * 	Legacy property for setting the power state of the connector. For atomic
924  * 	drivers this is only provided for backwards compatibility with existing
925  * 	drivers, it remaps to controlling the "ACTIVE" property on the CRTC the
926  * 	connector is linked to. Drivers should never set this property directly,
927  * 	it is handled by the DRM core by calling the &drm_connector_funcs.dpms
928  * 	callback. For atomic drivers the remapping to the "ACTIVE" property is
929  * 	implemented in the DRM core.  This is the only standard connector
930  * 	property that userspace can change.
931  *
932  * 	Note that this property cannot be set through the MODE_ATOMIC ioctl,
933  * 	userspace must use "ACTIVE" on the CRTC instead.
934  *
935  * 	WARNING:
936  *
937  * 	For userspace also running on legacy drivers the "DPMS" semantics are a
938  * 	lot more complicated. First, userspace cannot rely on the "DPMS" value
939  * 	returned by the GETCONNECTOR actually reflecting reality, because many
940  * 	drivers fail to update it. For atomic drivers this is taken care of in
941  * 	drm_atomic_helper_update_legacy_modeset_state().
942  *
943  * 	The second issue is that the DPMS state is only well-defined when the
944  * 	connector is connected to a CRTC. In atomic the DRM core enforces that
945  * 	"ACTIVE" is off in such a case, no such checks exists for "DPMS".
946  *
947  * 	Finally, when enabling an output using the legacy SETCONFIG ioctl then
948  * 	"DPMS" is forced to ON. But see above, that might not be reflected in
949  * 	the software value on legacy drivers.
950  *
951  * 	Summarizing: Only set "DPMS" when the connector is known to be enabled,
952  * 	assume that a successful SETCONFIG call also sets "DPMS" to on, and
953  * 	never read back the value of "DPMS" because it can be incorrect.
954  * PATH:
955  * 	Connector path property to identify how this sink is physically
956  * 	connected. Used by DP MST. This should be set by calling
957  * 	drm_connector_set_path_property(), in the case of DP MST with the
958  * 	path property the MST manager created. Userspace cannot change this
959  * 	property.
960  * TILE:
961  * 	Connector tile group property to indicate how a set of DRM connector
962  * 	compose together into one logical screen. This is used by both high-res
963  * 	external screens (often only using a single cable, but exposing multiple
964  * 	DP MST sinks), or high-res integrated panels (like dual-link DSI) which
965  * 	are not gen-locked. Note that for tiled panels which are genlocked, like
966  * 	dual-link LVDS or dual-link DSI, the driver should try to not expose the
967  * 	tiling and virtualize both &drm_crtc and &drm_plane if needed. Drivers
968  * 	should update this value using drm_connector_set_tile_property().
969  * 	Userspace cannot change this property.
970  * link-status:
971  *      Connector link-status property to indicate the status of link. The
972  *      default value of link-status is "GOOD". If something fails during or
973  *      after modeset, the kernel driver may set this to "BAD" and issue a
974  *      hotplug uevent. Drivers should update this value using
975  *      drm_connector_set_link_status_property().
976  * non_desktop:
977  * 	Indicates the output should be ignored for purposes of displaying a
978  * 	standard desktop environment or console. This is most likely because
979  * 	the output device is not rectilinear.
980  * Content Protection:
981  *	This property is used by userspace to request the kernel protect future
982  *	content communicated over the link. When requested, kernel will apply
983  *	the appropriate means of protection (most often HDCP), and use the
984  *	property to tell userspace the protection is active.
985  *
986  *	Drivers can set this up by calling
987  *	drm_connector_attach_content_protection_property() on initialization.
988  *
989  *	The value of this property can be one of the following:
990  *
991  *	DRM_MODE_CONTENT_PROTECTION_UNDESIRED = 0
992  *		The link is not protected, content is transmitted in the clear.
993  *	DRM_MODE_CONTENT_PROTECTION_DESIRED = 1
994  *		Userspace has requested content protection, but the link is not
995  *		currently protected. When in this state, kernel should enable
996  *		Content Protection as soon as possible.
997  *	DRM_MODE_CONTENT_PROTECTION_ENABLED = 2
998  *		Userspace has requested content protection, and the link is
999  *		protected. Only the driver can set the property to this value.
1000  *		If userspace attempts to set to ENABLED, kernel will return
1001  *		-EINVAL.
1002  *
1003  *	A few guidelines:
1004  *
1005  *	- DESIRED state should be preserved until userspace de-asserts it by
1006  *	  setting the property to UNDESIRED. This means ENABLED should only
1007  *	  transition to UNDESIRED when the user explicitly requests it.
1008  *	- If the state is DESIRED, kernel should attempt to re-authenticate the
1009  *	  link whenever possible. This includes across disable/enable, dpms,
1010  *	  hotplug, downstream device changes, link status failures, etc..
1011  *	- Kernel sends uevent with the connector id and property id through
1012  *	  @drm_hdcp_update_content_protection, upon below kernel triggered
1013  *	  scenarios:
1014  *
1015  *		- DESIRED -> ENABLED (authentication success)
1016  *		- ENABLED -> DESIRED (termination of authentication)
1017  *	- Please note no uevents for userspace triggered property state changes,
1018  *	  which can't fail such as
1019  *
1020  *		- DESIRED/ENABLED -> UNDESIRED
1021  *		- UNDESIRED -> DESIRED
1022  *	- Userspace is responsible for polling the property or listen to uevents
1023  *	  to determine when the value transitions from ENABLED to DESIRED.
1024  *	  This signifies the link is no longer protected and userspace should
1025  *	  take appropriate action (whatever that might be).
1026  *
1027  * HDCP Content Type:
1028  *	This Enum property is used by the userspace to declare the content type
1029  *	of the display stream, to kernel. Here display stream stands for any
1030  *	display content that userspace intended to display through HDCP
1031  *	encryption.
1032  *
1033  *	Content Type of a stream is decided by the owner of the stream, as
1034  *	"HDCP Type0" or "HDCP Type1".
1035  *
1036  *	The value of the property can be one of the below:
1037  *	  - "HDCP Type0": DRM_MODE_HDCP_CONTENT_TYPE0 = 0
1038  *	  - "HDCP Type1": DRM_MODE_HDCP_CONTENT_TYPE1 = 1
1039  *
1040  *	When kernel starts the HDCP authentication (see "Content Protection"
1041  *	for details), it uses the content type in "HDCP Content Type"
1042  *	for performing the HDCP authentication with the display sink.
1043  *
1044  *	Please note in HDCP spec versions, a link can be authenticated with
1045  *	HDCP 2.2 for Content Type 0/Content Type 1. Where as a link can be
1046  *	authenticated with HDCP1.4 only for Content Type 0(though it is implicit
1047  *	in nature. As there is no reference for Content Type in HDCP1.4).
1048  *
1049  *	HDCP2.2 authentication protocol itself takes the "Content Type" as a
1050  *	parameter, which is a input for the DP HDCP2.2 encryption algo.
1051  *
1052  *	In case of Type 0 content protection request, kernel driver can choose
1053  *	either of HDCP spec versions 1.4 and 2.2. When HDCP2.2 is used for
1054  *	"HDCP Type 0", a HDCP 2.2 capable repeater in the downstream can send
1055  *	that content to a HDCP 1.4 authenticated HDCP sink (Type0 link).
1056  *	But if the content is classified as "HDCP Type 1", above mentioned
1057  *	HDCP 2.2 repeater wont send the content to the HDCP sink as it can't
1058  *	authenticate the HDCP1.4 capable sink for "HDCP Type 1".
1059  *
1060  *	Please note userspace can be ignorant of the HDCP versions used by the
1061  *	kernel driver to achieve the "HDCP Content Type".
1062  *
1063  *	At current scenario, classifying a content as Type 1 ensures that the
1064  *	content will be displayed only through the HDCP2.2 encrypted link.
1065  *
1066  *	Note that the HDCP Content Type property is introduced at HDCP 2.2, and
1067  *	defaults to type 0. It is only exposed by drivers supporting HDCP 2.2
1068  *	(hence supporting Type 0 and Type 1). Based on how next versions of
1069  *	HDCP specs are defined content Type could be used for higher versions
1070  *	too.
1071  *
1072  *	If content type is changed when "Content Protection" is not UNDESIRED,
1073  *	then kernel will disable the HDCP and re-enable with new type in the
1074  *	same atomic commit. And when "Content Protection" is ENABLED, it means
1075  *	that link is HDCP authenticated and encrypted, for the transmission of
1076  *	the Type of stream mentioned at "HDCP Content Type".
1077  *
1078  * HDR_OUTPUT_METADATA:
1079  *	Connector property to enable userspace to send HDR Metadata to
1080  *	driver. This metadata is based on the composition and blending
1081  *	policies decided by user, taking into account the hardware and
1082  *	sink capabilities. The driver gets this metadata and creates a
1083  *	Dynamic Range and Mastering Infoframe (DRM) in case of HDMI,
1084  *	SDP packet (Non-audio INFOFRAME SDP v1.3) for DP. This is then
1085  *	sent to sink. This notifies the sink of the upcoming frame's Color
1086  *	Encoding and Luminance parameters.
1087  *
1088  *	Userspace first need to detect the HDR capabilities of sink by
1089  *	reading and parsing the EDID. Details of HDR metadata for HDMI
1090  *	are added in CTA 861.G spec. For DP , its defined in VESA DP
1091  *	Standard v1.4. It needs to then get the metadata information
1092  *	of the video/game/app content which are encoded in HDR (basically
1093  *	using HDR transfer functions). With this information it needs to
1094  *	decide on a blending policy and compose the relevant
1095  *	layers/overlays into a common format. Once this blending is done,
1096  *	userspace will be aware of the metadata of the composed frame to
1097  *	be send to sink. It then uses this property to communicate this
1098  *	metadata to driver which then make a Infoframe packet and sends
1099  *	to sink based on the type of encoder connected.
1100  *
1101  *	Userspace will be responsible to do Tone mapping operation in case:
1102  *		- Some layers are HDR and others are SDR
1103  *		- HDR layers luminance is not same as sink
1104  *
1105  *	It will even need to do colorspace conversion and get all layers
1106  *	to one common colorspace for blending. It can use either GL, Media
1107  *	or display engine to get this done based on the capabilties of the
1108  *	associated hardware.
1109  *
1110  *	Driver expects metadata to be put in &struct hdr_output_metadata
1111  *	structure from userspace. This is received as blob and stored in
1112  *	&drm_connector_state.hdr_output_metadata. It parses EDID and saves the
1113  *	sink metadata in &struct hdr_sink_metadata, as
1114  *	&drm_connector.hdr_sink_metadata.  Driver uses
1115  *	drm_hdmi_infoframe_set_hdr_metadata() helper to set the HDR metadata,
1116  *	hdmi_drm_infoframe_pack() to pack the infoframe as per spec, in case of
1117  *	HDMI encoder.
1118  *
1119  * max bpc:
1120  *	This range property is used by userspace to limit the bit depth. When
1121  *	used the driver would limit the bpc in accordance with the valid range
1122  *	supported by the hardware and sink. Drivers to use the function
1123  *	drm_connector_attach_max_bpc_property() to create and attach the
1124  *	property to the connector during initialization.
1125  *
1126  * Connectors also have one standardized atomic property:
1127  *
1128  * CRTC_ID:
1129  * 	Mode object ID of the &drm_crtc this connector should be connected to.
1130  *
1131  * Connectors for LCD panels may also have one standardized property:
1132  *
1133  * panel orientation:
1134  *	On some devices the LCD panel is mounted in the casing in such a way
1135  *	that the up/top side of the panel does not match with the top side of
1136  *	the device. Userspace can use this property to check for this.
1137  *	Note that input coordinates from touchscreens (input devices with
1138  *	INPUT_PROP_DIRECT) will still map 1:1 to the actual LCD panel
1139  *	coordinates, so if userspace rotates the picture to adjust for
1140  *	the orientation it must also apply the same transformation to the
1141  *	touchscreen input coordinates. This property is initialized by calling
1142  *	drm_connector_init_panel_orientation_property().
1143  *
1144  * scaling mode:
1145  *	This property defines how a non-native mode is upscaled to the native
1146  *	mode of an LCD panel:
1147  *
1148  *	None:
1149  *		No upscaling happens, scaling is left to the panel. Not all
1150  *		drivers expose this mode.
1151  *	Full:
1152  *		The output is upscaled to the full resolution of the panel,
1153  *		ignoring the aspect ratio.
1154  *	Center:
1155  *		No upscaling happens, the output is centered within the native
1156  *		resolution the panel.
1157  *	Full aspect:
1158  *		The output is upscaled to maximize either the width or height
1159  *		while retaining the aspect ratio.
1160  *
1161  *	This property should be set up by calling
1162  *	drm_connector_attach_scaling_mode_property(). Note that drivers
1163  *	can also expose this property to external outputs, in which case they
1164  *	must support "None", which should be the default (since external screens
1165  *	have a built-in scaler).
1166  */
1167 
1168 int drm_connector_create_standard_properties(struct drm_device *dev)
1169 {
1170 	struct drm_property *prop;
1171 
1172 	prop = drm_property_create(dev, DRM_MODE_PROP_BLOB |
1173 				   DRM_MODE_PROP_IMMUTABLE,
1174 				   "EDID", 0);
1175 	if (!prop)
1176 		return -ENOMEM;
1177 	dev->mode_config.edid_property = prop;
1178 
1179 	prop = drm_property_create_enum(dev, 0,
1180 				   "DPMS", drm_dpms_enum_list,
1181 				   ARRAY_SIZE(drm_dpms_enum_list));
1182 	if (!prop)
1183 		return -ENOMEM;
1184 	dev->mode_config.dpms_property = prop;
1185 
1186 	prop = drm_property_create(dev,
1187 				   DRM_MODE_PROP_BLOB |
1188 				   DRM_MODE_PROP_IMMUTABLE,
1189 				   "PATH", 0);
1190 	if (!prop)
1191 		return -ENOMEM;
1192 	dev->mode_config.path_property = prop;
1193 
1194 	prop = drm_property_create(dev,
1195 				   DRM_MODE_PROP_BLOB |
1196 				   DRM_MODE_PROP_IMMUTABLE,
1197 				   "TILE", 0);
1198 	if (!prop)
1199 		return -ENOMEM;
1200 	dev->mode_config.tile_property = prop;
1201 
1202 	prop = drm_property_create_enum(dev, 0, "link-status",
1203 					drm_link_status_enum_list,
1204 					ARRAY_SIZE(drm_link_status_enum_list));
1205 	if (!prop)
1206 		return -ENOMEM;
1207 	dev->mode_config.link_status_property = prop;
1208 
1209 	prop = drm_property_create_bool(dev, DRM_MODE_PROP_IMMUTABLE, "non-desktop");
1210 	if (!prop)
1211 		return -ENOMEM;
1212 	dev->mode_config.non_desktop_property = prop;
1213 
1214 	prop = drm_property_create(dev, DRM_MODE_PROP_BLOB,
1215 				   "HDR_OUTPUT_METADATA", 0);
1216 	if (!prop)
1217 		return -ENOMEM;
1218 	dev->mode_config.hdr_output_metadata_property = prop;
1219 
1220 	return 0;
1221 }
1222 
1223 /**
1224  * drm_mode_create_dvi_i_properties - create DVI-I specific connector properties
1225  * @dev: DRM device
1226  *
1227  * Called by a driver the first time a DVI-I connector is made.
1228  */
1229 int drm_mode_create_dvi_i_properties(struct drm_device *dev)
1230 {
1231 	struct drm_property *dvi_i_selector;
1232 	struct drm_property *dvi_i_subconnector;
1233 
1234 	if (dev->mode_config.dvi_i_select_subconnector_property)
1235 		return 0;
1236 
1237 	dvi_i_selector =
1238 		drm_property_create_enum(dev, 0,
1239 				    "select subconnector",
1240 				    drm_dvi_i_select_enum_list,
1241 				    ARRAY_SIZE(drm_dvi_i_select_enum_list));
1242 	dev->mode_config.dvi_i_select_subconnector_property = dvi_i_selector;
1243 
1244 	dvi_i_subconnector = drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
1245 				    "subconnector",
1246 				    drm_dvi_i_subconnector_enum_list,
1247 				    ARRAY_SIZE(drm_dvi_i_subconnector_enum_list));
1248 	dev->mode_config.dvi_i_subconnector_property = dvi_i_subconnector;
1249 
1250 	return 0;
1251 }
1252 EXPORT_SYMBOL(drm_mode_create_dvi_i_properties);
1253 
1254 /**
1255  * DOC: HDMI connector properties
1256  *
1257  * content type (HDMI specific):
1258  *	Indicates content type setting to be used in HDMI infoframes to indicate
1259  *	content type for the external device, so that it adjusts its display
1260  *	settings accordingly.
1261  *
1262  *	The value of this property can be one of the following:
1263  *
1264  *	No Data:
1265  *		Content type is unknown
1266  *	Graphics:
1267  *		Content type is graphics
1268  *	Photo:
1269  *		Content type is photo
1270  *	Cinema:
1271  *		Content type is cinema
1272  *	Game:
1273  *		Content type is game
1274  *
1275  *	Drivers can set up this property by calling
1276  *	drm_connector_attach_content_type_property(). Decoding to
1277  *	infoframe values is done through drm_hdmi_avi_infoframe_content_type().
1278  */
1279 
1280 /**
1281  * drm_connector_attach_content_type_property - attach content-type property
1282  * @connector: connector to attach content type property on.
1283  *
1284  * Called by a driver the first time a HDMI connector is made.
1285  */
1286 int drm_connector_attach_content_type_property(struct drm_connector *connector)
1287 {
1288 	if (!drm_mode_create_content_type_property(connector->dev))
1289 		drm_object_attach_property(&connector->base,
1290 					   connector->dev->mode_config.content_type_property,
1291 					   DRM_MODE_CONTENT_TYPE_NO_DATA);
1292 	return 0;
1293 }
1294 EXPORT_SYMBOL(drm_connector_attach_content_type_property);
1295 
1296 
1297 /**
1298  * drm_hdmi_avi_infoframe_content_type() - fill the HDMI AVI infoframe
1299  *                                         content type information, based
1300  *                                         on correspondent DRM property.
1301  * @frame: HDMI AVI infoframe
1302  * @conn_state: DRM display connector state
1303  *
1304  */
1305 void drm_hdmi_avi_infoframe_content_type(struct hdmi_avi_infoframe *frame,
1306 					 const struct drm_connector_state *conn_state)
1307 {
1308 	switch (conn_state->content_type) {
1309 	case DRM_MODE_CONTENT_TYPE_GRAPHICS:
1310 		frame->content_type = HDMI_CONTENT_TYPE_GRAPHICS;
1311 		break;
1312 	case DRM_MODE_CONTENT_TYPE_CINEMA:
1313 		frame->content_type = HDMI_CONTENT_TYPE_CINEMA;
1314 		break;
1315 	case DRM_MODE_CONTENT_TYPE_GAME:
1316 		frame->content_type = HDMI_CONTENT_TYPE_GAME;
1317 		break;
1318 	case DRM_MODE_CONTENT_TYPE_PHOTO:
1319 		frame->content_type = HDMI_CONTENT_TYPE_PHOTO;
1320 		break;
1321 	default:
1322 		/* Graphics is the default(0) */
1323 		frame->content_type = HDMI_CONTENT_TYPE_GRAPHICS;
1324 	}
1325 
1326 	frame->itc = conn_state->content_type != DRM_MODE_CONTENT_TYPE_NO_DATA;
1327 }
1328 EXPORT_SYMBOL(drm_hdmi_avi_infoframe_content_type);
1329 
1330 /**
1331  * drm_mode_attach_tv_margin_properties - attach TV connector margin properties
1332  * @connector: DRM connector
1333  *
1334  * Called by a driver when it needs to attach TV margin props to a connector.
1335  * Typically used on SDTV and HDMI connectors.
1336  */
1337 void drm_connector_attach_tv_margin_properties(struct drm_connector *connector)
1338 {
1339 	struct drm_device *dev = connector->dev;
1340 
1341 	drm_object_attach_property(&connector->base,
1342 				   dev->mode_config.tv_left_margin_property,
1343 				   0);
1344 	drm_object_attach_property(&connector->base,
1345 				   dev->mode_config.tv_right_margin_property,
1346 				   0);
1347 	drm_object_attach_property(&connector->base,
1348 				   dev->mode_config.tv_top_margin_property,
1349 				   0);
1350 	drm_object_attach_property(&connector->base,
1351 				   dev->mode_config.tv_bottom_margin_property,
1352 				   0);
1353 }
1354 EXPORT_SYMBOL(drm_connector_attach_tv_margin_properties);
1355 
1356 /**
1357  * drm_mode_create_tv_margin_properties - create TV connector margin properties
1358  * @dev: DRM device
1359  *
1360  * Called by a driver's HDMI connector initialization routine, this function
1361  * creates the TV margin properties for a given device. No need to call this
1362  * function for an SDTV connector, it's already called from
1363  * drm_mode_create_tv_properties().
1364  */
1365 int drm_mode_create_tv_margin_properties(struct drm_device *dev)
1366 {
1367 	if (dev->mode_config.tv_left_margin_property)
1368 		return 0;
1369 
1370 	dev->mode_config.tv_left_margin_property =
1371 		drm_property_create_range(dev, 0, "left margin", 0, 100);
1372 	if (!dev->mode_config.tv_left_margin_property)
1373 		return -ENOMEM;
1374 
1375 	dev->mode_config.tv_right_margin_property =
1376 		drm_property_create_range(dev, 0, "right margin", 0, 100);
1377 	if (!dev->mode_config.tv_right_margin_property)
1378 		return -ENOMEM;
1379 
1380 	dev->mode_config.tv_top_margin_property =
1381 		drm_property_create_range(dev, 0, "top margin", 0, 100);
1382 	if (!dev->mode_config.tv_top_margin_property)
1383 		return -ENOMEM;
1384 
1385 	dev->mode_config.tv_bottom_margin_property =
1386 		drm_property_create_range(dev, 0, "bottom margin", 0, 100);
1387 	if (!dev->mode_config.tv_bottom_margin_property)
1388 		return -ENOMEM;
1389 
1390 	return 0;
1391 }
1392 EXPORT_SYMBOL(drm_mode_create_tv_margin_properties);
1393 
1394 /**
1395  * drm_mode_create_tv_properties - create TV specific connector properties
1396  * @dev: DRM device
1397  * @num_modes: number of different TV formats (modes) supported
1398  * @modes: array of pointers to strings containing name of each format
1399  *
1400  * Called by a driver's TV initialization routine, this function creates
1401  * the TV specific connector properties for a given device.  Caller is
1402  * responsible for allocating a list of format names and passing them to
1403  * this routine.
1404  */
1405 int drm_mode_create_tv_properties(struct drm_device *dev,
1406 				  unsigned int num_modes,
1407 				  const char * const modes[])
1408 {
1409 	struct drm_property *tv_selector;
1410 	struct drm_property *tv_subconnector;
1411 	unsigned int i;
1412 
1413 	if (dev->mode_config.tv_select_subconnector_property)
1414 		return 0;
1415 
1416 	/*
1417 	 * Basic connector properties
1418 	 */
1419 	tv_selector = drm_property_create_enum(dev, 0,
1420 					  "select subconnector",
1421 					  drm_tv_select_enum_list,
1422 					  ARRAY_SIZE(drm_tv_select_enum_list));
1423 	if (!tv_selector)
1424 		goto nomem;
1425 
1426 	dev->mode_config.tv_select_subconnector_property = tv_selector;
1427 
1428 	tv_subconnector =
1429 		drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
1430 				    "subconnector",
1431 				    drm_tv_subconnector_enum_list,
1432 				    ARRAY_SIZE(drm_tv_subconnector_enum_list));
1433 	if (!tv_subconnector)
1434 		goto nomem;
1435 	dev->mode_config.tv_subconnector_property = tv_subconnector;
1436 
1437 	/*
1438 	 * Other, TV specific properties: margins & TV modes.
1439 	 */
1440 	if (drm_mode_create_tv_margin_properties(dev))
1441 		goto nomem;
1442 
1443 	dev->mode_config.tv_mode_property =
1444 		drm_property_create(dev, DRM_MODE_PROP_ENUM,
1445 				    "mode", num_modes);
1446 	if (!dev->mode_config.tv_mode_property)
1447 		goto nomem;
1448 
1449 	for (i = 0; i < num_modes; i++)
1450 		drm_property_add_enum(dev->mode_config.tv_mode_property,
1451 				      i, modes[i]);
1452 
1453 	dev->mode_config.tv_brightness_property =
1454 		drm_property_create_range(dev, 0, "brightness", 0, 100);
1455 	if (!dev->mode_config.tv_brightness_property)
1456 		goto nomem;
1457 
1458 	dev->mode_config.tv_contrast_property =
1459 		drm_property_create_range(dev, 0, "contrast", 0, 100);
1460 	if (!dev->mode_config.tv_contrast_property)
1461 		goto nomem;
1462 
1463 	dev->mode_config.tv_flicker_reduction_property =
1464 		drm_property_create_range(dev, 0, "flicker reduction", 0, 100);
1465 	if (!dev->mode_config.tv_flicker_reduction_property)
1466 		goto nomem;
1467 
1468 	dev->mode_config.tv_overscan_property =
1469 		drm_property_create_range(dev, 0, "overscan", 0, 100);
1470 	if (!dev->mode_config.tv_overscan_property)
1471 		goto nomem;
1472 
1473 	dev->mode_config.tv_saturation_property =
1474 		drm_property_create_range(dev, 0, "saturation", 0, 100);
1475 	if (!dev->mode_config.tv_saturation_property)
1476 		goto nomem;
1477 
1478 	dev->mode_config.tv_hue_property =
1479 		drm_property_create_range(dev, 0, "hue", 0, 100);
1480 	if (!dev->mode_config.tv_hue_property)
1481 		goto nomem;
1482 
1483 	return 0;
1484 nomem:
1485 	return -ENOMEM;
1486 }
1487 EXPORT_SYMBOL(drm_mode_create_tv_properties);
1488 
1489 /**
1490  * drm_mode_create_scaling_mode_property - create scaling mode property
1491  * @dev: DRM device
1492  *
1493  * Called by a driver the first time it's needed, must be attached to desired
1494  * connectors.
1495  *
1496  * Atomic drivers should use drm_connector_attach_scaling_mode_property()
1497  * instead to correctly assign &drm_connector_state.picture_aspect_ratio
1498  * in the atomic state.
1499  */
1500 int drm_mode_create_scaling_mode_property(struct drm_device *dev)
1501 {
1502 	struct drm_property *scaling_mode;
1503 
1504 	if (dev->mode_config.scaling_mode_property)
1505 		return 0;
1506 
1507 	scaling_mode =
1508 		drm_property_create_enum(dev, 0, "scaling mode",
1509 				drm_scaling_mode_enum_list,
1510 				    ARRAY_SIZE(drm_scaling_mode_enum_list));
1511 
1512 	dev->mode_config.scaling_mode_property = scaling_mode;
1513 
1514 	return 0;
1515 }
1516 EXPORT_SYMBOL(drm_mode_create_scaling_mode_property);
1517 
1518 /**
1519  * DOC: Variable refresh properties
1520  *
1521  * Variable refresh rate capable displays can dynamically adjust their
1522  * refresh rate by extending the duration of their vertical front porch
1523  * until page flip or timeout occurs. This can reduce or remove stuttering
1524  * and latency in scenarios where the page flip does not align with the
1525  * vblank interval.
1526  *
1527  * An example scenario would be an application flipping at a constant rate
1528  * of 48Hz on a 60Hz display. The page flip will frequently miss the vblank
1529  * interval and the same contents will be displayed twice. This can be
1530  * observed as stuttering for content with motion.
1531  *
1532  * If variable refresh rate was active on a display that supported a
1533  * variable refresh range from 35Hz to 60Hz no stuttering would be observable
1534  * for the example scenario. The minimum supported variable refresh rate of
1535  * 35Hz is below the page flip frequency and the vertical front porch can
1536  * be extended until the page flip occurs. The vblank interval will be
1537  * directly aligned to the page flip rate.
1538  *
1539  * Not all userspace content is suitable for use with variable refresh rate.
1540  * Large and frequent changes in vertical front porch duration may worsen
1541  * perceived stuttering for input sensitive applications.
1542  *
1543  * Panel brightness will also vary with vertical front porch duration. Some
1544  * panels may have noticeable differences in brightness between the minimum
1545  * vertical front porch duration and the maximum vertical front porch duration.
1546  * Large and frequent changes in vertical front porch duration may produce
1547  * observable flickering for such panels.
1548  *
1549  * Userspace control for variable refresh rate is supported via properties
1550  * on the &drm_connector and &drm_crtc objects.
1551  *
1552  * "vrr_capable":
1553  *	Optional &drm_connector boolean property that drivers should attach
1554  *	with drm_connector_attach_vrr_capable_property() on connectors that
1555  *	could support variable refresh rates. Drivers should update the
1556  *	property value by calling drm_connector_set_vrr_capable_property().
1557  *
1558  *	Absence of the property should indicate absence of support.
1559  *
1560  * "VRR_ENABLED":
1561  *	Default &drm_crtc boolean property that notifies the driver that the
1562  *	content on the CRTC is suitable for variable refresh rate presentation.
1563  *	The driver will take this property as a hint to enable variable
1564  *	refresh rate support if the receiver supports it, ie. if the
1565  *	"vrr_capable" property is true on the &drm_connector object. The
1566  *	vertical front porch duration will be extended until page-flip or
1567  *	timeout when enabled.
1568  *
1569  *	The minimum vertical front porch duration is defined as the vertical
1570  *	front porch duration for the current mode.
1571  *
1572  *	The maximum vertical front porch duration is greater than or equal to
1573  *	the minimum vertical front porch duration. The duration is derived
1574  *	from the minimum supported variable refresh rate for the connector.
1575  *
1576  *	The driver may place further restrictions within these minimum
1577  *	and maximum bounds.
1578  */
1579 
1580 /**
1581  * drm_connector_attach_vrr_capable_property - creates the
1582  * vrr_capable property
1583  * @connector: connector to create the vrr_capable property on.
1584  *
1585  * This is used by atomic drivers to add support for querying
1586  * variable refresh rate capability for a connector.
1587  *
1588  * Returns:
1589  * Zero on success, negative errono on failure.
1590  */
1591 int drm_connector_attach_vrr_capable_property(
1592 	struct drm_connector *connector)
1593 {
1594 	struct drm_device *dev = connector->dev;
1595 	struct drm_property *prop;
1596 
1597 	if (!connector->vrr_capable_property) {
1598 		prop = drm_property_create_bool(dev, DRM_MODE_PROP_IMMUTABLE,
1599 			"vrr_capable");
1600 		if (!prop)
1601 			return -ENOMEM;
1602 
1603 		connector->vrr_capable_property = prop;
1604 		drm_object_attach_property(&connector->base, prop, 0);
1605 	}
1606 
1607 	return 0;
1608 }
1609 EXPORT_SYMBOL(drm_connector_attach_vrr_capable_property);
1610 
1611 /**
1612  * drm_connector_attach_scaling_mode_property - attach atomic scaling mode property
1613  * @connector: connector to attach scaling mode property on.
1614  * @scaling_mode_mask: or'ed mask of BIT(%DRM_MODE_SCALE_\*).
1615  *
1616  * This is used to add support for scaling mode to atomic drivers.
1617  * The scaling mode will be set to &drm_connector_state.picture_aspect_ratio
1618  * and can be used from &drm_connector_helper_funcs->atomic_check for validation.
1619  *
1620  * This is the atomic version of drm_mode_create_scaling_mode_property().
1621  *
1622  * Returns:
1623  * Zero on success, negative errno on failure.
1624  */
1625 int drm_connector_attach_scaling_mode_property(struct drm_connector *connector,
1626 					       u32 scaling_mode_mask)
1627 {
1628 	struct drm_device *dev = connector->dev;
1629 	struct drm_property *scaling_mode_property;
1630 	int i;
1631 	const unsigned valid_scaling_mode_mask =
1632 		(1U << ARRAY_SIZE(drm_scaling_mode_enum_list)) - 1;
1633 
1634 	if (WARN_ON(hweight32(scaling_mode_mask) < 2 ||
1635 		    scaling_mode_mask & ~valid_scaling_mode_mask))
1636 		return -EINVAL;
1637 
1638 	scaling_mode_property =
1639 		drm_property_create(dev, DRM_MODE_PROP_ENUM, "scaling mode",
1640 				    hweight32(scaling_mode_mask));
1641 
1642 	if (!scaling_mode_property)
1643 		return -ENOMEM;
1644 
1645 	for (i = 0; i < ARRAY_SIZE(drm_scaling_mode_enum_list); i++) {
1646 		int ret;
1647 
1648 		if (!(BIT(i) & scaling_mode_mask))
1649 			continue;
1650 
1651 		ret = drm_property_add_enum(scaling_mode_property,
1652 					    drm_scaling_mode_enum_list[i].type,
1653 					    drm_scaling_mode_enum_list[i].name);
1654 
1655 		if (ret) {
1656 			drm_property_destroy(dev, scaling_mode_property);
1657 
1658 			return ret;
1659 		}
1660 	}
1661 
1662 	drm_object_attach_property(&connector->base,
1663 				   scaling_mode_property, 0);
1664 
1665 	connector->scaling_mode_property = scaling_mode_property;
1666 
1667 	return 0;
1668 }
1669 EXPORT_SYMBOL(drm_connector_attach_scaling_mode_property);
1670 
1671 /**
1672  * drm_mode_create_aspect_ratio_property - create aspect ratio property
1673  * @dev: DRM device
1674  *
1675  * Called by a driver the first time it's needed, must be attached to desired
1676  * connectors.
1677  *
1678  * Returns:
1679  * Zero on success, negative errno on failure.
1680  */
1681 int drm_mode_create_aspect_ratio_property(struct drm_device *dev)
1682 {
1683 	if (dev->mode_config.aspect_ratio_property)
1684 		return 0;
1685 
1686 	dev->mode_config.aspect_ratio_property =
1687 		drm_property_create_enum(dev, 0, "aspect ratio",
1688 				drm_aspect_ratio_enum_list,
1689 				ARRAY_SIZE(drm_aspect_ratio_enum_list));
1690 
1691 	if (dev->mode_config.aspect_ratio_property == NULL)
1692 		return -ENOMEM;
1693 
1694 	return 0;
1695 }
1696 EXPORT_SYMBOL(drm_mode_create_aspect_ratio_property);
1697 
1698 /**
1699  * DOC: standard connector properties
1700  *
1701  * Colorspace:
1702  *     This property helps select a suitable colorspace based on the sink
1703  *     capability. Modern sink devices support wider gamut like BT2020.
1704  *     This helps switch to BT2020 mode if the BT2020 encoded video stream
1705  *     is being played by the user, same for any other colorspace. Thereby
1706  *     giving a good visual experience to users.
1707  *
1708  *     The expectation from userspace is that it should parse the EDID
1709  *     and get supported colorspaces. Use this property and switch to the
1710  *     one supported. Sink supported colorspaces should be retrieved by
1711  *     userspace from EDID and driver will not explicitly expose them.
1712  *
1713  *     Basically the expectation from userspace is:
1714  *      - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink
1715  *        colorspace
1716  *      - Set this new property to let the sink know what it
1717  *        converted the CRTC output to.
1718  *      - This property is just to inform sink what colorspace
1719  *        source is trying to drive.
1720  *
1721  * Because between HDMI and DP have different colorspaces,
1722  * drm_mode_create_hdmi_colorspace_property() is used for HDMI connector and
1723  * drm_mode_create_dp_colorspace_property() is used for DP connector.
1724  */
1725 
1726 /**
1727  * drm_mode_create_hdmi_colorspace_property - create hdmi colorspace property
1728  * @connector: connector to create the Colorspace property on.
1729  *
1730  * Called by a driver the first time it's needed, must be attached to desired
1731  * HDMI connectors.
1732  *
1733  * Returns:
1734  * Zero on success, negative errono on failure.
1735  */
1736 int drm_mode_create_hdmi_colorspace_property(struct drm_connector *connector)
1737 {
1738 	struct drm_device *dev = connector->dev;
1739 
1740 	if (connector->colorspace_property)
1741 		return 0;
1742 
1743 	connector->colorspace_property =
1744 		drm_property_create_enum(dev, DRM_MODE_PROP_ENUM, "Colorspace",
1745 					 hdmi_colorspaces,
1746 					 ARRAY_SIZE(hdmi_colorspaces));
1747 
1748 	if (!connector->colorspace_property)
1749 		return -ENOMEM;
1750 
1751 	return 0;
1752 }
1753 EXPORT_SYMBOL(drm_mode_create_hdmi_colorspace_property);
1754 
1755 /**
1756  * drm_mode_create_dp_colorspace_property - create dp colorspace property
1757  * @connector: connector to create the Colorspace property on.
1758  *
1759  * Called by a driver the first time it's needed, must be attached to desired
1760  * DP connectors.
1761  *
1762  * Returns:
1763  * Zero on success, negative errono on failure.
1764  */
1765 int drm_mode_create_dp_colorspace_property(struct drm_connector *connector)
1766 {
1767 	struct drm_device *dev = connector->dev;
1768 
1769 	if (connector->colorspace_property)
1770 		return 0;
1771 
1772 	connector->colorspace_property =
1773 		drm_property_create_enum(dev, DRM_MODE_PROP_ENUM, "Colorspace",
1774 					 dp_colorspaces,
1775 					 ARRAY_SIZE(dp_colorspaces));
1776 
1777 	if (!connector->colorspace_property)
1778 		return -ENOMEM;
1779 
1780 	return 0;
1781 }
1782 EXPORT_SYMBOL(drm_mode_create_dp_colorspace_property);
1783 
1784 /**
1785  * drm_mode_create_content_type_property - create content type property
1786  * @dev: DRM device
1787  *
1788  * Called by a driver the first time it's needed, must be attached to desired
1789  * connectors.
1790  *
1791  * Returns:
1792  * Zero on success, negative errno on failure.
1793  */
1794 int drm_mode_create_content_type_property(struct drm_device *dev)
1795 {
1796 	if (dev->mode_config.content_type_property)
1797 		return 0;
1798 
1799 	dev->mode_config.content_type_property =
1800 		drm_property_create_enum(dev, 0, "content type",
1801 					 drm_content_type_enum_list,
1802 					 ARRAY_SIZE(drm_content_type_enum_list));
1803 
1804 	if (dev->mode_config.content_type_property == NULL)
1805 		return -ENOMEM;
1806 
1807 	return 0;
1808 }
1809 EXPORT_SYMBOL(drm_mode_create_content_type_property);
1810 
1811 /**
1812  * drm_mode_create_suggested_offset_properties - create suggests offset properties
1813  * @dev: DRM device
1814  *
1815  * Create the the suggested x/y offset property for connectors.
1816  */
1817 int drm_mode_create_suggested_offset_properties(struct drm_device *dev)
1818 {
1819 	if (dev->mode_config.suggested_x_property && dev->mode_config.suggested_y_property)
1820 		return 0;
1821 
1822 	dev->mode_config.suggested_x_property =
1823 		drm_property_create_range(dev, DRM_MODE_PROP_IMMUTABLE, "suggested X", 0, 0xffffffff);
1824 
1825 	dev->mode_config.suggested_y_property =
1826 		drm_property_create_range(dev, DRM_MODE_PROP_IMMUTABLE, "suggested Y", 0, 0xffffffff);
1827 
1828 	if (dev->mode_config.suggested_x_property == NULL ||
1829 	    dev->mode_config.suggested_y_property == NULL)
1830 		return -ENOMEM;
1831 	return 0;
1832 }
1833 EXPORT_SYMBOL(drm_mode_create_suggested_offset_properties);
1834 
1835 /**
1836  * drm_connector_set_path_property - set tile property on connector
1837  * @connector: connector to set property on.
1838  * @path: path to use for property; must not be NULL.
1839  *
1840  * This creates a property to expose to userspace to specify a
1841  * connector path. This is mainly used for DisplayPort MST where
1842  * connectors have a topology and we want to allow userspace to give
1843  * them more meaningful names.
1844  *
1845  * Returns:
1846  * Zero on success, negative errno on failure.
1847  */
1848 int drm_connector_set_path_property(struct drm_connector *connector,
1849 				    const char *path)
1850 {
1851 	struct drm_device *dev = connector->dev;
1852 	int ret;
1853 
1854 	ret = drm_property_replace_global_blob(dev,
1855 	                                       &connector->path_blob_ptr,
1856 	                                       strlen(path) + 1,
1857 	                                       path,
1858 	                                       &connector->base,
1859 	                                       dev->mode_config.path_property);
1860 	return ret;
1861 }
1862 EXPORT_SYMBOL(drm_connector_set_path_property);
1863 
1864 /**
1865  * drm_connector_set_tile_property - set tile property on connector
1866  * @connector: connector to set property on.
1867  *
1868  * This looks up the tile information for a connector, and creates a
1869  * property for userspace to parse if it exists. The property is of
1870  * the form of 8 integers using ':' as a separator.
1871  * This is used for dual port tiled displays with DisplayPort SST
1872  * or DisplayPort MST connectors.
1873  *
1874  * Returns:
1875  * Zero on success, errno on failure.
1876  */
1877 int drm_connector_set_tile_property(struct drm_connector *connector)
1878 {
1879 	struct drm_device *dev = connector->dev;
1880 	char tile[256];
1881 	int ret;
1882 
1883 	if (!connector->has_tile) {
1884 		ret  = drm_property_replace_global_blob(dev,
1885 		                                        &connector->tile_blob_ptr,
1886 		                                        0,
1887 		                                        NULL,
1888 		                                        &connector->base,
1889 		                                        dev->mode_config.tile_property);
1890 		return ret;
1891 	}
1892 
1893 	snprintf(tile, 256, "%d:%d:%d:%d:%d:%d:%d:%d",
1894 		 connector->tile_group->id, connector->tile_is_single_monitor,
1895 		 connector->num_h_tile, connector->num_v_tile,
1896 		 connector->tile_h_loc, connector->tile_v_loc,
1897 		 connector->tile_h_size, connector->tile_v_size);
1898 
1899 	ret = drm_property_replace_global_blob(dev,
1900 	                                       &connector->tile_blob_ptr,
1901 	                                       strlen(tile) + 1,
1902 	                                       tile,
1903 	                                       &connector->base,
1904 	                                       dev->mode_config.tile_property);
1905 	return ret;
1906 }
1907 EXPORT_SYMBOL(drm_connector_set_tile_property);
1908 
1909 /**
1910  * drm_connector_update_edid_property - update the edid property of a connector
1911  * @connector: drm connector
1912  * @edid: new value of the edid property
1913  *
1914  * This function creates a new blob modeset object and assigns its id to the
1915  * connector's edid property.
1916  * Since we also parse tile information from EDID's displayID block, we also
1917  * set the connector's tile property here. See drm_connector_set_tile_property()
1918  * for more details.
1919  *
1920  * Returns:
1921  * Zero on success, negative errno on failure.
1922  */
1923 int drm_connector_update_edid_property(struct drm_connector *connector,
1924 				       const struct edid *edid)
1925 {
1926 	struct drm_device *dev = connector->dev;
1927 	size_t size = 0;
1928 	int ret;
1929 
1930 	/* ignore requests to set edid when overridden */
1931 	if (connector->override_edid)
1932 		return 0;
1933 
1934 	if (edid)
1935 		size = EDID_LENGTH * (1 + edid->extensions);
1936 
1937 	/* Set the display info, using edid if available, otherwise
1938 	 * reseting the values to defaults. This duplicates the work
1939 	 * done in drm_add_edid_modes, but that function is not
1940 	 * consistently called before this one in all drivers and the
1941 	 * computation is cheap enough that it seems better to
1942 	 * duplicate it rather than attempt to ensure some arbitrary
1943 	 * ordering of calls.
1944 	 */
1945 	if (edid)
1946 		drm_add_display_info(connector, edid);
1947 	else
1948 		drm_reset_display_info(connector);
1949 
1950 	drm_object_property_set_value(&connector->base,
1951 				      dev->mode_config.non_desktop_property,
1952 				      connector->display_info.non_desktop);
1953 
1954 	ret = drm_property_replace_global_blob(dev,
1955 					       &connector->edid_blob_ptr,
1956 	                                       size,
1957 	                                       edid,
1958 	                                       &connector->base,
1959 	                                       dev->mode_config.edid_property);
1960 	if (ret)
1961 		return ret;
1962 	return drm_connector_set_tile_property(connector);
1963 }
1964 EXPORT_SYMBOL(drm_connector_update_edid_property);
1965 
1966 /**
1967  * drm_connector_set_link_status_property - Set link status property of a connector
1968  * @connector: drm connector
1969  * @link_status: new value of link status property (0: Good, 1: Bad)
1970  *
1971  * In usual working scenario, this link status property will always be set to
1972  * "GOOD". If something fails during or after a mode set, the kernel driver
1973  * may set this link status property to "BAD". The caller then needs to send a
1974  * hotplug uevent for userspace to re-check the valid modes through
1975  * GET_CONNECTOR_IOCTL and retry modeset.
1976  *
1977  * Note: Drivers cannot rely on userspace to support this property and
1978  * issue a modeset. As such, they may choose to handle issues (like
1979  * re-training a link) without userspace's intervention.
1980  *
1981  * The reason for adding this property is to handle link training failures, but
1982  * it is not limited to DP or link training. For example, if we implement
1983  * asynchronous setcrtc, this property can be used to report any failures in that.
1984  */
1985 void drm_connector_set_link_status_property(struct drm_connector *connector,
1986 					    uint64_t link_status)
1987 {
1988 	struct drm_device *dev = connector->dev;
1989 
1990 	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
1991 	connector->state->link_status = link_status;
1992 	drm_modeset_unlock(&dev->mode_config.connection_mutex);
1993 }
1994 EXPORT_SYMBOL(drm_connector_set_link_status_property);
1995 
1996 /**
1997  * drm_connector_attach_max_bpc_property - attach "max bpc" property
1998  * @connector: connector to attach max bpc property on.
1999  * @min: The minimum bit depth supported by the connector.
2000  * @max: The maximum bit depth supported by the connector.
2001  *
2002  * This is used to add support for limiting the bit depth on a connector.
2003  *
2004  * Returns:
2005  * Zero on success, negative errno on failure.
2006  */
2007 int drm_connector_attach_max_bpc_property(struct drm_connector *connector,
2008 					  int min, int max)
2009 {
2010 	struct drm_device *dev = connector->dev;
2011 	struct drm_property *prop;
2012 
2013 	prop = connector->max_bpc_property;
2014 	if (!prop) {
2015 		prop = drm_property_create_range(dev, 0, "max bpc", min, max);
2016 		if (!prop)
2017 			return -ENOMEM;
2018 
2019 		connector->max_bpc_property = prop;
2020 	}
2021 
2022 	drm_object_attach_property(&connector->base, prop, max);
2023 	connector->state->max_requested_bpc = max;
2024 	connector->state->max_bpc = max;
2025 
2026 	return 0;
2027 }
2028 EXPORT_SYMBOL(drm_connector_attach_max_bpc_property);
2029 
2030 /**
2031  * drm_connector_set_vrr_capable_property - sets the variable refresh rate
2032  * capable property for a connector
2033  * @connector: drm connector
2034  * @capable: True if the connector is variable refresh rate capable
2035  *
2036  * Should be used by atomic drivers to update the indicated support for
2037  * variable refresh rate over a connector.
2038  */
2039 void drm_connector_set_vrr_capable_property(
2040 		struct drm_connector *connector, bool capable)
2041 {
2042 	drm_object_property_set_value(&connector->base,
2043 				      connector->vrr_capable_property,
2044 				      capable);
2045 }
2046 EXPORT_SYMBOL(drm_connector_set_vrr_capable_property);
2047 
2048 /**
2049  * drm_connector_init_panel_orientation_property -
2050  *	initialize the connecters panel_orientation property
2051  * @connector: connector for which to init the panel-orientation property.
2052  * @width: width in pixels of the panel, used for panel quirk detection
2053  * @height: height in pixels of the panel, used for panel quirk detection
2054  *
2055  * This function should only be called for built-in panels, after setting
2056  * connector->display_info.panel_orientation first (if known).
2057  *
2058  * This function will check for platform specific (e.g. DMI based) quirks
2059  * overriding display_info.panel_orientation first, then if panel_orientation
2060  * is not DRM_MODE_PANEL_ORIENTATION_UNKNOWN it will attach the
2061  * "panel orientation" property to the connector.
2062  *
2063  * Returns:
2064  * Zero on success, negative errno on failure.
2065  */
2066 int drm_connector_init_panel_orientation_property(
2067 	struct drm_connector *connector, int width, int height)
2068 {
2069 	struct drm_device *dev = connector->dev;
2070 	struct drm_display_info *info = &connector->display_info;
2071 	struct drm_property *prop;
2072 	int orientation_quirk;
2073 
2074 	orientation_quirk = drm_get_panel_orientation_quirk(width, height);
2075 	if (orientation_quirk != DRM_MODE_PANEL_ORIENTATION_UNKNOWN)
2076 		info->panel_orientation = orientation_quirk;
2077 
2078 	if (info->panel_orientation == DRM_MODE_PANEL_ORIENTATION_UNKNOWN)
2079 		return 0;
2080 
2081 	prop = dev->mode_config.panel_orientation_property;
2082 	if (!prop) {
2083 		prop = drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
2084 				"panel orientation",
2085 				drm_panel_orientation_enum_list,
2086 				ARRAY_SIZE(drm_panel_orientation_enum_list));
2087 		if (!prop)
2088 			return -ENOMEM;
2089 
2090 		dev->mode_config.panel_orientation_property = prop;
2091 	}
2092 
2093 	drm_object_attach_property(&connector->base, prop,
2094 				   info->panel_orientation);
2095 	return 0;
2096 }
2097 EXPORT_SYMBOL(drm_connector_init_panel_orientation_property);
2098 
2099 int drm_connector_set_obj_prop(struct drm_mode_object *obj,
2100 				    struct drm_property *property,
2101 				    uint64_t value)
2102 {
2103 	int ret = -EINVAL;
2104 	struct drm_connector *connector = obj_to_connector(obj);
2105 
2106 	/* Do DPMS ourselves */
2107 	if (property == connector->dev->mode_config.dpms_property) {
2108 		ret = (*connector->funcs->dpms)(connector, (int)value);
2109 	} else if (connector->funcs->set_property)
2110 		ret = connector->funcs->set_property(connector, property, value);
2111 
2112 	if (!ret)
2113 		drm_object_property_set_value(&connector->base, property, value);
2114 	return ret;
2115 }
2116 
2117 int drm_connector_property_set_ioctl(struct drm_device *dev,
2118 				     void *data, struct drm_file *file_priv)
2119 {
2120 	struct drm_mode_connector_set_property *conn_set_prop = data;
2121 	struct drm_mode_obj_set_property obj_set_prop = {
2122 		.value = conn_set_prop->value,
2123 		.prop_id = conn_set_prop->prop_id,
2124 		.obj_id = conn_set_prop->connector_id,
2125 		.obj_type = DRM_MODE_OBJECT_CONNECTOR
2126 	};
2127 
2128 	/* It does all the locking and checking we need */
2129 	return drm_mode_obj_set_property_ioctl(dev, &obj_set_prop, file_priv);
2130 }
2131 
2132 static struct drm_encoder *drm_connector_get_encoder(struct drm_connector *connector)
2133 {
2134 	/* For atomic drivers only state objects are synchronously updated and
2135 	 * protected by modeset locks, so check those first. */
2136 	if (connector->state)
2137 		return connector->state->best_encoder;
2138 	return connector->encoder;
2139 }
2140 
2141 static bool
2142 drm_mode_expose_to_userspace(const struct drm_display_mode *mode,
2143 			     const struct list_head *export_list,
2144 			     const struct drm_file *file_priv)
2145 {
2146 	/*
2147 	 * If user-space hasn't configured the driver to expose the stereo 3D
2148 	 * modes, don't expose them.
2149 	 */
2150 	if (!file_priv->stereo_allowed && drm_mode_is_stereo(mode))
2151 		return false;
2152 	/*
2153 	 * If user-space hasn't configured the driver to expose the modes
2154 	 * with aspect-ratio, don't expose them. However if such a mode
2155 	 * is unique, let it be exposed, but reset the aspect-ratio flags
2156 	 * while preparing the list of user-modes.
2157 	 */
2158 	if (!file_priv->aspect_ratio_allowed) {
2159 		struct drm_display_mode *mode_itr;
2160 
2161 		list_for_each_entry(mode_itr, export_list, export_head)
2162 			if (drm_mode_match(mode_itr, mode,
2163 					   DRM_MODE_MATCH_TIMINGS |
2164 					   DRM_MODE_MATCH_CLOCK |
2165 					   DRM_MODE_MATCH_FLAGS |
2166 					   DRM_MODE_MATCH_3D_FLAGS))
2167 				return false;
2168 	}
2169 
2170 	return true;
2171 }
2172 
2173 int drm_mode_getconnector(struct drm_device *dev, void *data,
2174 			  struct drm_file *file_priv)
2175 {
2176 	struct drm_mode_get_connector *out_resp = data;
2177 	struct drm_connector *connector;
2178 	struct drm_encoder *encoder;
2179 	struct drm_display_mode *mode;
2180 	int mode_count = 0;
2181 	int encoders_count = 0;
2182 	int ret = 0;
2183 	int copied = 0;
2184 	struct drm_mode_modeinfo u_mode;
2185 	struct drm_mode_modeinfo __user *mode_ptr;
2186 	uint32_t __user *encoder_ptr;
2187 	LIST_HEAD(export_list);
2188 
2189 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
2190 		return -EOPNOTSUPP;
2191 
2192 	memset(&u_mode, 0, sizeof(struct drm_mode_modeinfo));
2193 
2194 	connector = drm_connector_lookup(dev, file_priv, out_resp->connector_id);
2195 	if (!connector)
2196 		return -ENOENT;
2197 
2198 	encoders_count = hweight32(connector->possible_encoders);
2199 
2200 	if ((out_resp->count_encoders >= encoders_count) && encoders_count) {
2201 		copied = 0;
2202 		encoder_ptr = (uint32_t __user *)(unsigned long)(out_resp->encoders_ptr);
2203 
2204 		drm_connector_for_each_possible_encoder(connector, encoder) {
2205 			if (put_user(encoder->base.id, encoder_ptr + copied)) {
2206 				ret = -EFAULT;
2207 				goto out;
2208 			}
2209 			copied++;
2210 		}
2211 	}
2212 	out_resp->count_encoders = encoders_count;
2213 
2214 	out_resp->connector_id = connector->base.id;
2215 	out_resp->connector_type = connector->connector_type;
2216 	out_resp->connector_type_id = connector->connector_type_id;
2217 
2218 	mutex_lock(&dev->mode_config.mutex);
2219 	if (out_resp->count_modes == 0) {
2220 		connector->funcs->fill_modes(connector,
2221 					     dev->mode_config.max_width,
2222 					     dev->mode_config.max_height);
2223 	}
2224 
2225 	out_resp->mm_width = connector->display_info.width_mm;
2226 	out_resp->mm_height = connector->display_info.height_mm;
2227 	out_resp->subpixel = connector->display_info.subpixel_order;
2228 	out_resp->connection = connector->status;
2229 
2230 	/* delayed so we get modes regardless of pre-fill_modes state */
2231 	list_for_each_entry(mode, &connector->modes, head)
2232 		if (drm_mode_expose_to_userspace(mode, &export_list,
2233 						 file_priv)) {
2234 			list_add_tail(&mode->export_head, &export_list);
2235 			mode_count++;
2236 		}
2237 
2238 	/*
2239 	 * This ioctl is called twice, once to determine how much space is
2240 	 * needed, and the 2nd time to fill it.
2241 	 * The modes that need to be exposed to the user are maintained in the
2242 	 * 'export_list'. When the ioctl is called first time to determine the,
2243 	 * space, the export_list gets filled, to find the no.of modes. In the
2244 	 * 2nd time, the user modes are filled, one by one from the export_list.
2245 	 */
2246 	if ((out_resp->count_modes >= mode_count) && mode_count) {
2247 		copied = 0;
2248 		mode_ptr = (struct drm_mode_modeinfo __user *)(unsigned long)out_resp->modes_ptr;
2249 		list_for_each_entry(mode, &export_list, export_head) {
2250 			drm_mode_convert_to_umode(&u_mode, mode);
2251 			/*
2252 			 * Reset aspect ratio flags of user-mode, if modes with
2253 			 * aspect-ratio are not supported.
2254 			 */
2255 			if (!file_priv->aspect_ratio_allowed)
2256 				u_mode.flags &= ~DRM_MODE_FLAG_PIC_AR_MASK;
2257 			if (copy_to_user(mode_ptr + copied,
2258 					 &u_mode, sizeof(u_mode))) {
2259 				ret = -EFAULT;
2260 				mutex_unlock(&dev->mode_config.mutex);
2261 
2262 				goto out;
2263 			}
2264 			copied++;
2265 		}
2266 	}
2267 	out_resp->count_modes = mode_count;
2268 	mutex_unlock(&dev->mode_config.mutex);
2269 
2270 	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
2271 	encoder = drm_connector_get_encoder(connector);
2272 	if (encoder)
2273 		out_resp->encoder_id = encoder->base.id;
2274 	else
2275 		out_resp->encoder_id = 0;
2276 
2277 	/* Only grab properties after probing, to make sure EDID and other
2278 	 * properties reflect the latest status. */
2279 	ret = drm_mode_object_get_properties(&connector->base, file_priv->atomic,
2280 			(uint32_t __user *)(unsigned long)(out_resp->props_ptr),
2281 			(uint64_t __user *)(unsigned long)(out_resp->prop_values_ptr),
2282 			&out_resp->count_props);
2283 	drm_modeset_unlock(&dev->mode_config.connection_mutex);
2284 
2285 out:
2286 	drm_connector_put(connector);
2287 
2288 	return ret;
2289 }
2290 
2291 
2292 /**
2293  * DOC: Tile group
2294  *
2295  * Tile groups are used to represent tiled monitors with a unique integer
2296  * identifier. Tiled monitors using DisplayID v1.3 have a unique 8-byte handle,
2297  * we store this in a tile group, so we have a common identifier for all tiles
2298  * in a monitor group. The property is called "TILE". Drivers can manage tile
2299  * groups using drm_mode_create_tile_group(), drm_mode_put_tile_group() and
2300  * drm_mode_get_tile_group(). But this is only needed for internal panels where
2301  * the tile group information is exposed through a non-standard way.
2302  */
2303 
2304 static void drm_tile_group_free(struct kref *kref)
2305 {
2306 	struct drm_tile_group *tg = container_of(kref, struct drm_tile_group, refcount);
2307 	struct drm_device *dev = tg->dev;
2308 	mutex_lock(&dev->mode_config.idr_mutex);
2309 	idr_remove(&dev->mode_config.tile_idr, tg->id);
2310 	mutex_unlock(&dev->mode_config.idr_mutex);
2311 	kfree(tg);
2312 }
2313 
2314 /**
2315  * drm_mode_put_tile_group - drop a reference to a tile group.
2316  * @dev: DRM device
2317  * @tg: tile group to drop reference to.
2318  *
2319  * drop reference to tile group and free if 0.
2320  */
2321 void drm_mode_put_tile_group(struct drm_device *dev,
2322 			     struct drm_tile_group *tg)
2323 {
2324 	kref_put(&tg->refcount, drm_tile_group_free);
2325 }
2326 EXPORT_SYMBOL(drm_mode_put_tile_group);
2327 
2328 /**
2329  * drm_mode_get_tile_group - get a reference to an existing tile group
2330  * @dev: DRM device
2331  * @topology: 8-bytes unique per monitor.
2332  *
2333  * Use the unique bytes to get a reference to an existing tile group.
2334  *
2335  * RETURNS:
2336  * tile group or NULL if not found.
2337  */
2338 struct drm_tile_group *drm_mode_get_tile_group(struct drm_device *dev,
2339 					       char topology[8])
2340 {
2341 	struct drm_tile_group *tg;
2342 	int id;
2343 	mutex_lock(&dev->mode_config.idr_mutex);
2344 	idr_for_each_entry(&dev->mode_config.tile_idr, tg, id) {
2345 		if (!memcmp(tg->group_data, topology, 8)) {
2346 			if (!kref_get_unless_zero(&tg->refcount))
2347 				tg = NULL;
2348 			mutex_unlock(&dev->mode_config.idr_mutex);
2349 			return tg;
2350 		}
2351 	}
2352 	mutex_unlock(&dev->mode_config.idr_mutex);
2353 	return NULL;
2354 }
2355 EXPORT_SYMBOL(drm_mode_get_tile_group);
2356 
2357 /**
2358  * drm_mode_create_tile_group - create a tile group from a displayid description
2359  * @dev: DRM device
2360  * @topology: 8-bytes unique per monitor.
2361  *
2362  * Create a tile group for the unique monitor, and get a unique
2363  * identifier for the tile group.
2364  *
2365  * RETURNS:
2366  * new tile group or NULL.
2367  */
2368 struct drm_tile_group *drm_mode_create_tile_group(struct drm_device *dev,
2369 						  char topology[8])
2370 {
2371 	struct drm_tile_group *tg;
2372 	int ret;
2373 
2374 	tg = kzalloc(sizeof(*tg), GFP_KERNEL);
2375 	if (!tg)
2376 		return NULL;
2377 
2378 	kref_init(&tg->refcount);
2379 	memcpy(tg->group_data, topology, 8);
2380 	tg->dev = dev;
2381 
2382 	mutex_lock(&dev->mode_config.idr_mutex);
2383 	ret = idr_alloc(&dev->mode_config.tile_idr, tg, 1, 0, GFP_KERNEL);
2384 	if (ret >= 0) {
2385 		tg->id = ret;
2386 	} else {
2387 		kfree(tg);
2388 		tg = NULL;
2389 	}
2390 
2391 	mutex_unlock(&dev->mode_config.idr_mutex);
2392 	return tg;
2393 }
2394 EXPORT_SYMBOL(drm_mode_create_tile_group);
2395