xref: /dragonfly/sys/dev/drm/drm_connector.c (revision 9317c2d0)
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/drmP.h>
24 #include <drm/drm_connector.h>
25 #include <drm/drm_edid.h>
26 
27 #include "drm_crtc_internal.h"
28 #include "drm_internal.h"
29 
30 /**
31  * DOC: overview
32  *
33  * In DRM connectors are the general abstraction for display sinks, and include
34  * als fixed panels or anything else that can display pixels in some form. As
35  * opposed to all other KMS objects representing hardware (like CRTC, encoder or
36  * plane abstractions) connectors can be hotplugged and unplugged at runtime.
37  * Hence they are reference-counted using drm_connector_reference() and
38  * drm_connector_unreference().
39  *
40  * KMS driver must create, initialize, register and attach at a struct
41  * &drm_connector for each such sink. The instance is created as other KMS
42  * objects and initialized by setting the following fields.
43  *
44  * The connector is then registered with a call to drm_connector_init() with a
45  * pointer to the connector functions and a connector type, and exposed through
46  * sysfs with a call to drm_connector_register().
47  *
48  * Connectors must be attached to an encoder to be used. For devices that map
49  * connectors to encoders 1:1, the connector should be attached at
50  * initialization time with a call to drm_mode_connector_attach_encoder(). The
51  * driver must also set the struct &drm_connector encoder field to point to the
52  * attached encoder.
53  *
54  * For connectors which are not fixed (like built-in panels) the driver needs to
55  * support hotplug notifications. The simplest way to do that is by using the
56  * probe helpers, see drm_kms_helper_poll_init() for connectors which don't have
57  * hardware support for hotplug interrupts. Connectors with hardware hotplug
58  * support can instead use e.g. drm_helper_hpd_irq_event().
59  */
60 
61 struct drm_conn_prop_enum_list {
62 	int type;
63 	const char *name;
64 	struct ida ida;
65 };
66 
67 /*
68  * Connector and encoder types.
69  */
70 static struct drm_conn_prop_enum_list drm_connector_enum_list[] = {
71 	{ DRM_MODE_CONNECTOR_Unknown, "Unknown" },
72 	{ DRM_MODE_CONNECTOR_VGA, "VGA" },
73 	{ DRM_MODE_CONNECTOR_DVII, "DVI-I" },
74 	{ DRM_MODE_CONNECTOR_DVID, "DVI-D" },
75 	{ DRM_MODE_CONNECTOR_DVIA, "DVI-A" },
76 	{ DRM_MODE_CONNECTOR_Composite, "Composite" },
77 	{ DRM_MODE_CONNECTOR_SVIDEO, "SVIDEO" },
78 	{ DRM_MODE_CONNECTOR_LVDS, "LVDS" },
79 	{ DRM_MODE_CONNECTOR_Component, "Component" },
80 	{ DRM_MODE_CONNECTOR_9PinDIN, "DIN" },
81 	{ DRM_MODE_CONNECTOR_DisplayPort, "DP" },
82 	{ DRM_MODE_CONNECTOR_HDMIA, "HDMI-A" },
83 	{ DRM_MODE_CONNECTOR_HDMIB, "HDMI-B" },
84 	{ DRM_MODE_CONNECTOR_TV, "TV" },
85 	{ DRM_MODE_CONNECTOR_eDP, "eDP" },
86 	{ DRM_MODE_CONNECTOR_VIRTUAL, "Virtual" },
87 	{ DRM_MODE_CONNECTOR_DSI, "DSI" },
88 	{ DRM_MODE_CONNECTOR_DPI, "DPI" },
89 };
90 
91 void drm_connector_ida_init(void)
92 {
93 	int i;
94 
95 	for (i = 0; i < ARRAY_SIZE(drm_connector_enum_list); i++)
96 		ida_init(&drm_connector_enum_list[i].ida);
97 }
98 
99 void drm_connector_ida_destroy(void)
100 {
101 	int i;
102 
103 	for (i = 0; i < ARRAY_SIZE(drm_connector_enum_list); i++)
104 		ida_destroy(&drm_connector_enum_list[i].ida);
105 }
106 
107 /**
108  * drm_connector_get_cmdline_mode - reads the user's cmdline mode
109  * @connector: connector to quwery
110  *
111  * The kernel supports per-connector configuration of its consoles through
112  * use of the video= parameter. This function parses that option and
113  * extracts the user's specified mode (or enable/disable status) for a
114  * particular connector. This is typically only used during the early fbdev
115  * setup.
116  */
117 static void drm_connector_get_cmdline_mode(struct drm_connector *connector)
118 {
119 	struct drm_cmdline_mode *mode = &connector->cmdline_mode;
120 	char *option = NULL;
121 
122 	if (fb_get_options(connector->name, &option))
123 		return;
124 
125 	if (!drm_mode_parse_command_line_for_connector(option,
126 						       connector,
127 						       mode))
128 		return;
129 
130 	if (mode->force) {
131 		const char *s;
132 
133 		switch (mode->force) {
134 		case DRM_FORCE_OFF:
135 			s = "OFF";
136 			break;
137 		case DRM_FORCE_ON_DIGITAL:
138 			s = "ON - dig";
139 			break;
140 		default:
141 		case DRM_FORCE_ON:
142 			s = "ON";
143 			break;
144 		}
145 
146 		DRM_INFO("forcing %s connector %s\n", connector->name, s);
147 		connector->force = mode->force;
148 	}
149 
150 	DRM_DEBUG_KMS("cmdline mode for connector %s %dx%d@%dHz%s%s%s\n",
151 		      connector->name,
152 		      mode->xres, mode->yres,
153 		      mode->refresh_specified ? mode->refresh : 60,
154 		      mode->rb ? " reduced blanking" : "",
155 		      mode->margins ? " with margins" : "",
156 		      mode->interlace ?  " interlaced" : "");
157 }
158 
159 static void drm_connector_free(struct kref *kref)
160 {
161 	struct drm_connector *connector =
162 		container_of(kref, struct drm_connector, base.refcount);
163 	struct drm_device *dev = connector->dev;
164 
165 	drm_mode_object_unregister(dev, &connector->base);
166 	connector->funcs->destroy(connector);
167 }
168 
169 /**
170  * drm_connector_init - Init a preallocated connector
171  * @dev: DRM device
172  * @connector: the connector to init
173  * @funcs: callbacks for this connector
174  * @connector_type: user visible type of the connector
175  *
176  * Initialises a preallocated connector. Connectors should be
177  * subclassed as part of driver connector objects.
178  *
179  * Returns:
180  * Zero on success, error code on failure.
181  */
182 int drm_connector_init(struct drm_device *dev,
183 		       struct drm_connector *connector,
184 		       const struct drm_connector_funcs *funcs,
185 		       int connector_type)
186 {
187 	struct drm_mode_config *config = &dev->mode_config;
188 	int ret;
189 	struct ida *connector_ida =
190 		&drm_connector_enum_list[connector_type].ida;
191 
192 	drm_modeset_lock_all(dev);
193 
194 	ret = drm_mode_object_get_reg(dev, &connector->base,
195 				      DRM_MODE_OBJECT_CONNECTOR,
196 				      false, drm_connector_free);
197 	if (ret)
198 		goto out_unlock;
199 
200 	connector->base.properties = &connector->properties;
201 	connector->dev = dev;
202 	connector->funcs = funcs;
203 
204 	ret = ida_simple_get(&config->connector_ida, 0, 0, GFP_KERNEL);
205 	if (ret < 0)
206 		goto out_put;
207 	connector->index = ret;
208 	ret = 0;
209 
210 	connector->connector_type = connector_type;
211 	connector->connector_type_id =
212 		ida_simple_get(connector_ida, 1, 0, GFP_KERNEL);
213 	if (connector->connector_type_id < 0) {
214 		ret = connector->connector_type_id;
215 		goto out_put_id;
216 	}
217 	connector->name =
218 		kasprintf(GFP_KERNEL, "%s-%d",
219 			  drm_connector_enum_list[connector_type].name,
220 			  connector->connector_type_id);
221 	if (!connector->name) {
222 		ret = -ENOMEM;
223 		goto out_put_type_id;
224 	}
225 
226 	INIT_LIST_HEAD(&connector->probed_modes);
227 	INIT_LIST_HEAD(&connector->modes);
228 	lockinit(&connector->mutex, "drmcm", 0, LK_CANRECURSE);
229 	connector->edid_blob_ptr = NULL;
230 	connector->status = connector_status_unknown;
231 
232 	drm_connector_get_cmdline_mode(connector);
233 
234 	/* We should add connectors at the end to avoid upsetting the connector
235 	 * index too much. */
236 	list_add_tail(&connector->head, &config->connector_list);
237 	config->num_connector++;
238 
239 	if (connector_type != DRM_MODE_CONNECTOR_VIRTUAL)
240 		drm_object_attach_property(&connector->base,
241 					      config->edid_property,
242 					      0);
243 
244 	drm_object_attach_property(&connector->base,
245 				      config->dpms_property, 0);
246 
247 	if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
248 		drm_object_attach_property(&connector->base, config->prop_crtc_id, 0);
249 	}
250 
251 	connector->debugfs_entry = NULL;
252 out_put_type_id:
253 	if (ret)
254 		ida_simple_remove(connector_ida, connector->connector_type_id);
255 out_put_id:
256 	if (ret)
257 		ida_simple_remove(&config->connector_ida, connector->index);
258 out_put:
259 	if (ret)
260 		drm_mode_object_unregister(dev, &connector->base);
261 
262 out_unlock:
263 	drm_modeset_unlock_all(dev);
264 
265 	return ret;
266 }
267 EXPORT_SYMBOL(drm_connector_init);
268 
269 /**
270  * drm_mode_connector_attach_encoder - attach a connector to an encoder
271  * @connector: connector to attach
272  * @encoder: encoder to attach @connector to
273  *
274  * This function links up a connector to an encoder. Note that the routing
275  * restrictions between encoders and crtcs are exposed to userspace through the
276  * possible_clones and possible_crtcs bitmasks.
277  *
278  * Returns:
279  * Zero on success, negative errno on failure.
280  */
281 int drm_mode_connector_attach_encoder(struct drm_connector *connector,
282 				      struct drm_encoder *encoder)
283 {
284 	int i;
285 
286 	/*
287 	 * In the past, drivers have attempted to model the static association
288 	 * of connector to encoder in simple connector/encoder devices using a
289 	 * direct assignment of connector->encoder = encoder. This connection
290 	 * is a logical one and the responsibility of the core, so drivers are
291 	 * expected not to mess with this.
292 	 *
293 	 * Note that the error return should've been enough here, but a large
294 	 * majority of drivers ignores the return value, so add in a big WARN
295 	 * to get people's attention.
296 	 */
297 	if (WARN_ON(connector->encoder))
298 		return -EINVAL;
299 
300 	for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++) {
301 		if (connector->encoder_ids[i] == 0) {
302 			connector->encoder_ids[i] = encoder->base.id;
303 			return 0;
304 		}
305 	}
306 	return -ENOMEM;
307 }
308 EXPORT_SYMBOL(drm_mode_connector_attach_encoder);
309 
310 static void drm_mode_remove(struct drm_connector *connector,
311 			    struct drm_display_mode *mode)
312 {
313 	list_del(&mode->head);
314 	drm_mode_destroy(connector->dev, mode);
315 }
316 
317 /**
318  * drm_connector_cleanup - cleans up an initialised connector
319  * @connector: connector to cleanup
320  *
321  * Cleans up the connector but doesn't free the object.
322  */
323 void drm_connector_cleanup(struct drm_connector *connector)
324 {
325 	struct drm_device *dev = connector->dev;
326 	struct drm_display_mode *mode, *t;
327 
328 	/* The connector should have been removed from userspace long before
329 	 * it is finally destroyed.
330 	 */
331 	if (WARN_ON(connector->registered))
332 		drm_connector_unregister(connector);
333 
334 	if (connector->tile_group) {
335 		drm_mode_put_tile_group(dev, connector->tile_group);
336 		connector->tile_group = NULL;
337 	}
338 
339 	list_for_each_entry_safe(mode, t, &connector->probed_modes, head)
340 		drm_mode_remove(connector, mode);
341 
342 	list_for_each_entry_safe(mode, t, &connector->modes, head)
343 		drm_mode_remove(connector, mode);
344 
345 	ida_simple_remove(&drm_connector_enum_list[connector->connector_type].ida,
346 			  connector->connector_type_id);
347 
348 	ida_simple_remove(&dev->mode_config.connector_ida,
349 			  connector->index);
350 
351 	kfree(connector->display_info.bus_formats);
352 	drm_mode_object_unregister(dev, &connector->base);
353 	kfree(connector->name);
354 	connector->name = NULL;
355 	list_del(&connector->head);
356 	dev->mode_config.num_connector--;
357 
358 	WARN_ON(connector->state && !connector->funcs->atomic_destroy_state);
359 	if (connector->state && connector->funcs->atomic_destroy_state)
360 		connector->funcs->atomic_destroy_state(connector,
361 						       connector->state);
362 
363 	mutex_destroy(&connector->mutex);
364 
365 	memset(connector, 0, sizeof(*connector));
366 }
367 EXPORT_SYMBOL(drm_connector_cleanup);
368 
369 /**
370  * drm_connector_register - register a connector
371  * @connector: the connector to register
372  *
373  * Register userspace interfaces for a connector
374  *
375  * Returns:
376  * Zero on success, error code on failure.
377  */
378 int drm_connector_register(struct drm_connector *connector)
379 {
380 	int ret = 0;
381 
382 	if (!connector->dev->registered)
383 		return 0;
384 
385 	mutex_lock(&connector->mutex);
386 	if (connector->registered)
387 		goto unlock;
388 
389 	ret = drm_sysfs_connector_add(connector);
390 	if (ret)
391 		goto unlock;
392 
393 	ret = drm_debugfs_connector_add(connector);
394 	if (ret) {
395 		goto err_sysfs;
396 	}
397 
398 	if (connector->funcs->late_register) {
399 		ret = connector->funcs->late_register(connector);
400 		if (ret)
401 			goto err_debugfs;
402 	}
403 
404 	drm_mode_object_register(connector->dev, &connector->base);
405 
406 	connector->registered = true;
407 	goto unlock;
408 
409 err_debugfs:
410 	drm_debugfs_connector_remove(connector);
411 err_sysfs:
412 	drm_sysfs_connector_remove(connector);
413 unlock:
414 	mutex_unlock(&connector->mutex);
415 	return ret;
416 }
417 EXPORT_SYMBOL(drm_connector_register);
418 
419 /**
420  * drm_connector_unregister - unregister a connector
421  * @connector: the connector to unregister
422  *
423  * Unregister userspace interfaces for a connector
424  */
425 void drm_connector_unregister(struct drm_connector *connector)
426 {
427 	mutex_lock(&connector->mutex);
428 	if (!connector->registered) {
429 		mutex_unlock(&connector->mutex);
430 		return;
431 	}
432 
433 	if (connector->funcs->early_unregister)
434 		connector->funcs->early_unregister(connector);
435 
436 	drm_sysfs_connector_remove(connector);
437 	drm_debugfs_connector_remove(connector);
438 
439 	connector->registered = false;
440 	mutex_unlock(&connector->mutex);
441 }
442 EXPORT_SYMBOL(drm_connector_unregister);
443 
444 void drm_connector_unregister_all(struct drm_device *dev)
445 {
446 	struct drm_connector *connector;
447 
448 	/* FIXME: taking the mode config mutex ends up in a clash with sysfs */
449 	list_for_each_entry(connector, &dev->mode_config.connector_list, head)
450 		drm_connector_unregister(connector);
451 }
452 
453 int drm_connector_register_all(struct drm_device *dev)
454 {
455 	struct drm_connector *connector;
456 	int ret;
457 
458 	/* FIXME: taking the mode config mutex ends up in a clash with
459 	 * fbcon/backlight registration */
460 	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
461 		ret = drm_connector_register(connector);
462 		if (ret)
463 			goto err;
464 	}
465 
466 	return 0;
467 
468 err:
469 	mutex_unlock(&dev->mode_config.mutex);
470 	drm_connector_unregister_all(dev);
471 	return ret;
472 }
473 
474 /**
475  * drm_get_connector_status_name - return a string for connector status
476  * @status: connector status to compute name of
477  *
478  * In contrast to the other drm_get_*_name functions this one here returns a
479  * const pointer and hence is threadsafe.
480  */
481 const char *drm_get_connector_status_name(enum drm_connector_status status)
482 {
483 	if (status == connector_status_connected)
484 		return "connected";
485 	else if (status == connector_status_disconnected)
486 		return "disconnected";
487 	else
488 		return "unknown";
489 }
490 EXPORT_SYMBOL(drm_get_connector_status_name);
491 
492 static const struct drm_prop_enum_list drm_subpixel_enum_list[] = {
493 	{ SubPixelUnknown, "Unknown" },
494 	{ SubPixelHorizontalRGB, "Horizontal RGB" },
495 	{ SubPixelHorizontalBGR, "Horizontal BGR" },
496 	{ SubPixelVerticalRGB, "Vertical RGB" },
497 	{ SubPixelVerticalBGR, "Vertical BGR" },
498 	{ SubPixelNone, "None" },
499 };
500 
501 /**
502  * drm_get_subpixel_order_name - return a string for a given subpixel enum
503  * @order: enum of subpixel_order
504  *
505  * Note you could abuse this and return something out of bounds, but that
506  * would be a caller error.  No unscrubbed user data should make it here.
507  */
508 const char *drm_get_subpixel_order_name(enum subpixel_order order)
509 {
510 	return drm_subpixel_enum_list[order].name;
511 }
512 EXPORT_SYMBOL(drm_get_subpixel_order_name);
513 
514 static const struct drm_prop_enum_list drm_dpms_enum_list[] = {
515 	{ DRM_MODE_DPMS_ON, "On" },
516 	{ DRM_MODE_DPMS_STANDBY, "Standby" },
517 	{ DRM_MODE_DPMS_SUSPEND, "Suspend" },
518 	{ DRM_MODE_DPMS_OFF, "Off" }
519 };
520 DRM_ENUM_NAME_FN(drm_get_dpms_name, drm_dpms_enum_list)
521 
522 /**
523  * drm_display_info_set_bus_formats - set the supported bus formats
524  * @info: display info to store bus formats in
525  * @formats: array containing the supported bus formats
526  * @num_formats: the number of entries in the fmts array
527  *
528  * Store the supported bus formats in display info structure.
529  * See MEDIA_BUS_FMT_* definitions in include/uapi/linux/media-bus-format.h for
530  * a full list of available formats.
531  */
532 int drm_display_info_set_bus_formats(struct drm_display_info *info,
533 				     const u32 *formats,
534 				     unsigned int num_formats)
535 {
536 	u32 *fmts = NULL;
537 
538 	if (!formats && num_formats)
539 		return -EINVAL;
540 
541 	if (formats && num_formats) {
542 		fmts = kmemdup(formats, sizeof(*formats) * num_formats,
543 			       GFP_KERNEL);
544 		if (!fmts)
545 			return -ENOMEM;
546 	}
547 
548 	kfree(info->bus_formats);
549 	info->bus_formats = fmts;
550 	info->num_bus_formats = num_formats;
551 
552 	return 0;
553 }
554 EXPORT_SYMBOL(drm_display_info_set_bus_formats);
555 
556 /* Optional connector properties. */
557 static const struct drm_prop_enum_list drm_scaling_mode_enum_list[] = {
558 	{ DRM_MODE_SCALE_NONE, "None" },
559 	{ DRM_MODE_SCALE_FULLSCREEN, "Full" },
560 	{ DRM_MODE_SCALE_CENTER, "Center" },
561 	{ DRM_MODE_SCALE_ASPECT, "Full aspect" },
562 };
563 
564 static const struct drm_prop_enum_list drm_aspect_ratio_enum_list[] = {
565 	{ DRM_MODE_PICTURE_ASPECT_NONE, "Automatic" },
566 	{ DRM_MODE_PICTURE_ASPECT_4_3, "4:3" },
567 	{ DRM_MODE_PICTURE_ASPECT_16_9, "16:9" },
568 };
569 
570 static const struct drm_prop_enum_list drm_dvi_i_select_enum_list[] = {
571 	{ DRM_MODE_SUBCONNECTOR_Automatic, "Automatic" }, /* DVI-I and TV-out */
572 	{ DRM_MODE_SUBCONNECTOR_DVID,      "DVI-D"     }, /* DVI-I  */
573 	{ DRM_MODE_SUBCONNECTOR_DVIA,      "DVI-A"     }, /* DVI-I  */
574 };
575 DRM_ENUM_NAME_FN(drm_get_dvi_i_select_name, drm_dvi_i_select_enum_list)
576 
577 static const struct drm_prop_enum_list drm_dvi_i_subconnector_enum_list[] = {
578 	{ DRM_MODE_SUBCONNECTOR_Unknown,   "Unknown"   }, /* DVI-I and TV-out */
579 	{ DRM_MODE_SUBCONNECTOR_DVID,      "DVI-D"     }, /* DVI-I  */
580 	{ DRM_MODE_SUBCONNECTOR_DVIA,      "DVI-A"     }, /* DVI-I  */
581 };
582 DRM_ENUM_NAME_FN(drm_get_dvi_i_subconnector_name,
583 		 drm_dvi_i_subconnector_enum_list)
584 
585 static const struct drm_prop_enum_list drm_tv_select_enum_list[] = {
586 	{ DRM_MODE_SUBCONNECTOR_Automatic, "Automatic" }, /* DVI-I and TV-out */
587 	{ DRM_MODE_SUBCONNECTOR_Composite, "Composite" }, /* TV-out */
588 	{ DRM_MODE_SUBCONNECTOR_SVIDEO,    "SVIDEO"    }, /* TV-out */
589 	{ DRM_MODE_SUBCONNECTOR_Component, "Component" }, /* TV-out */
590 	{ DRM_MODE_SUBCONNECTOR_SCART,     "SCART"     }, /* TV-out */
591 };
592 DRM_ENUM_NAME_FN(drm_get_tv_select_name, drm_tv_select_enum_list)
593 
594 static const struct drm_prop_enum_list drm_tv_subconnector_enum_list[] = {
595 	{ DRM_MODE_SUBCONNECTOR_Unknown,   "Unknown"   }, /* DVI-I and TV-out */
596 	{ DRM_MODE_SUBCONNECTOR_Composite, "Composite" }, /* TV-out */
597 	{ DRM_MODE_SUBCONNECTOR_SVIDEO,    "SVIDEO"    }, /* TV-out */
598 	{ DRM_MODE_SUBCONNECTOR_Component, "Component" }, /* TV-out */
599 	{ DRM_MODE_SUBCONNECTOR_SCART,     "SCART"     }, /* TV-out */
600 };
601 DRM_ENUM_NAME_FN(drm_get_tv_subconnector_name,
602 		 drm_tv_subconnector_enum_list)
603 
604 /**
605  * DOC: standard connector properties
606  *
607  * DRM connectors have a few standardized properties:
608  *
609  * EDID:
610  * 	Blob property which contains the current EDID read from the sink. This
611  * 	is useful to parse sink identification information like vendor, model
612  * 	and serial. Drivers should update this property by calling
613  * 	drm_mode_connector_update_edid_property(), usually after having parsed
614  * 	the EDID using drm_add_edid_modes(). Userspace cannot change this
615  * 	property.
616  * DPMS:
617  * 	Legacy property for setting the power state of the connector. For atomic
618  * 	drivers this is only provided for backwards compatibility with existing
619  * 	drivers, it remaps to controlling the "ACTIVE" property on the CRTC the
620  * 	connector is linked to. Drivers should never set this property directly,
621  * 	it is handled by the DRM core by calling the ->dpms() callback in
622  * 	&drm_connector_funcs. Atomic drivers should implement this hook using
623  * 	drm_atomic_helper_connector_dpms(). This is the only property standard
624  * 	connector property that userspace can change.
625  * PATH:
626  * 	Connector path property to identify how this sink is physically
627  * 	connected. Used by DP MST. This should be set by calling
628  * 	drm_mode_connector_set_path_property(), in the case of DP MST with the
629  * 	path property the MST manager created. Userspace cannot change this
630  * 	property.
631  * TILE:
632  * 	Connector tile group property to indicate how a set of DRM connector
633  * 	compose together into one logical screen. This is used by both high-res
634  * 	external screens (often only using a single cable, but exposing multiple
635  * 	DP MST sinks), or high-res integrated panels (like dual-link DSI) which
636  * 	are not gen-locked. Note that for tiled panels which are genlocked, like
637  * 	dual-link LVDS or dual-link DSI, the driver should try to not expose the
638  * 	tiling and virtualize both &drm_crtc and &drm_plane if needed. Drivers
639  * 	should update this value using drm_mode_connector_set_tile_property().
640  * 	Userspace cannot change this property.
641  *
642  * Connectors also have one standardized atomic property:
643  *
644  * CRTC_ID:
645  * 	Mode object ID of the &drm_crtc this connector should be connected to.
646  */
647 
648 int drm_connector_create_standard_properties(struct drm_device *dev)
649 {
650 	struct drm_property *prop;
651 
652 	prop = drm_property_create(dev, DRM_MODE_PROP_BLOB |
653 				   DRM_MODE_PROP_IMMUTABLE,
654 				   "EDID", 0);
655 	if (!prop)
656 		return -ENOMEM;
657 	dev->mode_config.edid_property = prop;
658 
659 	prop = drm_property_create_enum(dev, 0,
660 				   "DPMS", drm_dpms_enum_list,
661 				   ARRAY_SIZE(drm_dpms_enum_list));
662 	if (!prop)
663 		return -ENOMEM;
664 	dev->mode_config.dpms_property = prop;
665 
666 	prop = drm_property_create(dev,
667 				   DRM_MODE_PROP_BLOB |
668 				   DRM_MODE_PROP_IMMUTABLE,
669 				   "PATH", 0);
670 	if (!prop)
671 		return -ENOMEM;
672 	dev->mode_config.path_property = prop;
673 
674 	prop = drm_property_create(dev,
675 				   DRM_MODE_PROP_BLOB |
676 				   DRM_MODE_PROP_IMMUTABLE,
677 				   "TILE", 0);
678 	if (!prop)
679 		return -ENOMEM;
680 	dev->mode_config.tile_property = prop;
681 
682 	return 0;
683 }
684 
685 /**
686  * drm_mode_create_dvi_i_properties - create DVI-I specific connector properties
687  * @dev: DRM device
688  *
689  * Called by a driver the first time a DVI-I connector is made.
690  */
691 int drm_mode_create_dvi_i_properties(struct drm_device *dev)
692 {
693 	struct drm_property *dvi_i_selector;
694 	struct drm_property *dvi_i_subconnector;
695 
696 	if (dev->mode_config.dvi_i_select_subconnector_property)
697 		return 0;
698 
699 	dvi_i_selector =
700 		drm_property_create_enum(dev, 0,
701 				    "select subconnector",
702 				    drm_dvi_i_select_enum_list,
703 				    ARRAY_SIZE(drm_dvi_i_select_enum_list));
704 	dev->mode_config.dvi_i_select_subconnector_property = dvi_i_selector;
705 
706 	dvi_i_subconnector = drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
707 				    "subconnector",
708 				    drm_dvi_i_subconnector_enum_list,
709 				    ARRAY_SIZE(drm_dvi_i_subconnector_enum_list));
710 	dev->mode_config.dvi_i_subconnector_property = dvi_i_subconnector;
711 
712 	return 0;
713 }
714 EXPORT_SYMBOL(drm_mode_create_dvi_i_properties);
715 
716 /**
717  * drm_create_tv_properties - create TV specific connector properties
718  * @dev: DRM device
719  * @num_modes: number of different TV formats (modes) supported
720  * @modes: array of pointers to strings containing name of each format
721  *
722  * Called by a driver's TV initialization routine, this function creates
723  * the TV specific connector properties for a given device.  Caller is
724  * responsible for allocating a list of format names and passing them to
725  * this routine.
726  */
727 int drm_mode_create_tv_properties(struct drm_device *dev,
728 				  unsigned int num_modes,
729 				  const char * const modes[])
730 {
731 	struct drm_property *tv_selector;
732 	struct drm_property *tv_subconnector;
733 	unsigned int i;
734 
735 	if (dev->mode_config.tv_select_subconnector_property)
736 		return 0;
737 
738 	/*
739 	 * Basic connector properties
740 	 */
741 	tv_selector = drm_property_create_enum(dev, 0,
742 					  "select subconnector",
743 					  drm_tv_select_enum_list,
744 					  ARRAY_SIZE(drm_tv_select_enum_list));
745 	if (!tv_selector)
746 		goto nomem;
747 
748 	dev->mode_config.tv_select_subconnector_property = tv_selector;
749 
750 	tv_subconnector =
751 		drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
752 				    "subconnector",
753 				    drm_tv_subconnector_enum_list,
754 				    ARRAY_SIZE(drm_tv_subconnector_enum_list));
755 	if (!tv_subconnector)
756 		goto nomem;
757 	dev->mode_config.tv_subconnector_property = tv_subconnector;
758 
759 	/*
760 	 * Other, TV specific properties: margins & TV modes.
761 	 */
762 	dev->mode_config.tv_left_margin_property =
763 		drm_property_create_range(dev, 0, "left margin", 0, 100);
764 	if (!dev->mode_config.tv_left_margin_property)
765 		goto nomem;
766 
767 	dev->mode_config.tv_right_margin_property =
768 		drm_property_create_range(dev, 0, "right margin", 0, 100);
769 	if (!dev->mode_config.tv_right_margin_property)
770 		goto nomem;
771 
772 	dev->mode_config.tv_top_margin_property =
773 		drm_property_create_range(dev, 0, "top margin", 0, 100);
774 	if (!dev->mode_config.tv_top_margin_property)
775 		goto nomem;
776 
777 	dev->mode_config.tv_bottom_margin_property =
778 		drm_property_create_range(dev, 0, "bottom margin", 0, 100);
779 	if (!dev->mode_config.tv_bottom_margin_property)
780 		goto nomem;
781 
782 	dev->mode_config.tv_mode_property =
783 		drm_property_create(dev, DRM_MODE_PROP_ENUM,
784 				    "mode", num_modes);
785 	if (!dev->mode_config.tv_mode_property)
786 		goto nomem;
787 
788 	for (i = 0; i < num_modes; i++)
789 		drm_property_add_enum(dev->mode_config.tv_mode_property, i,
790 				      i, modes[i]);
791 
792 	dev->mode_config.tv_brightness_property =
793 		drm_property_create_range(dev, 0, "brightness", 0, 100);
794 	if (!dev->mode_config.tv_brightness_property)
795 		goto nomem;
796 
797 	dev->mode_config.tv_contrast_property =
798 		drm_property_create_range(dev, 0, "contrast", 0, 100);
799 	if (!dev->mode_config.tv_contrast_property)
800 		goto nomem;
801 
802 	dev->mode_config.tv_flicker_reduction_property =
803 		drm_property_create_range(dev, 0, "flicker reduction", 0, 100);
804 	if (!dev->mode_config.tv_flicker_reduction_property)
805 		goto nomem;
806 
807 	dev->mode_config.tv_overscan_property =
808 		drm_property_create_range(dev, 0, "overscan", 0, 100);
809 	if (!dev->mode_config.tv_overscan_property)
810 		goto nomem;
811 
812 	dev->mode_config.tv_saturation_property =
813 		drm_property_create_range(dev, 0, "saturation", 0, 100);
814 	if (!dev->mode_config.tv_saturation_property)
815 		goto nomem;
816 
817 	dev->mode_config.tv_hue_property =
818 		drm_property_create_range(dev, 0, "hue", 0, 100);
819 	if (!dev->mode_config.tv_hue_property)
820 		goto nomem;
821 
822 	return 0;
823 nomem:
824 	return -ENOMEM;
825 }
826 EXPORT_SYMBOL(drm_mode_create_tv_properties);
827 
828 /**
829  * drm_mode_create_scaling_mode_property - create scaling mode property
830  * @dev: DRM device
831  *
832  * Called by a driver the first time it's needed, must be attached to desired
833  * connectors.
834  */
835 int drm_mode_create_scaling_mode_property(struct drm_device *dev)
836 {
837 	struct drm_property *scaling_mode;
838 
839 	if (dev->mode_config.scaling_mode_property)
840 		return 0;
841 
842 	scaling_mode =
843 		drm_property_create_enum(dev, 0, "scaling mode",
844 				drm_scaling_mode_enum_list,
845 				    ARRAY_SIZE(drm_scaling_mode_enum_list));
846 
847 	dev->mode_config.scaling_mode_property = scaling_mode;
848 
849 	return 0;
850 }
851 EXPORT_SYMBOL(drm_mode_create_scaling_mode_property);
852 
853 /**
854  * drm_mode_create_aspect_ratio_property - create aspect ratio property
855  * @dev: DRM device
856  *
857  * Called by a driver the first time it's needed, must be attached to desired
858  * connectors.
859  *
860  * Returns:
861  * Zero on success, negative errno on failure.
862  */
863 int drm_mode_create_aspect_ratio_property(struct drm_device *dev)
864 {
865 	if (dev->mode_config.aspect_ratio_property)
866 		return 0;
867 
868 	dev->mode_config.aspect_ratio_property =
869 		drm_property_create_enum(dev, 0, "aspect ratio",
870 				drm_aspect_ratio_enum_list,
871 				ARRAY_SIZE(drm_aspect_ratio_enum_list));
872 
873 	if (dev->mode_config.aspect_ratio_property == NULL)
874 		return -ENOMEM;
875 
876 	return 0;
877 }
878 EXPORT_SYMBOL(drm_mode_create_aspect_ratio_property);
879 
880 /**
881  * drm_mode_create_suggested_offset_properties - create suggests offset properties
882  * @dev: DRM device
883  *
884  * Create the the suggested x/y offset property for connectors.
885  */
886 int drm_mode_create_suggested_offset_properties(struct drm_device *dev)
887 {
888 	if (dev->mode_config.suggested_x_property && dev->mode_config.suggested_y_property)
889 		return 0;
890 
891 	dev->mode_config.suggested_x_property =
892 		drm_property_create_range(dev, DRM_MODE_PROP_IMMUTABLE, "suggested X", 0, 0xffffffff);
893 
894 	dev->mode_config.suggested_y_property =
895 		drm_property_create_range(dev, DRM_MODE_PROP_IMMUTABLE, "suggested Y", 0, 0xffffffff);
896 
897 	if (dev->mode_config.suggested_x_property == NULL ||
898 	    dev->mode_config.suggested_y_property == NULL)
899 		return -ENOMEM;
900 	return 0;
901 }
902 EXPORT_SYMBOL(drm_mode_create_suggested_offset_properties);
903 
904 /**
905  * drm_mode_connector_set_path_property - set tile property on connector
906  * @connector: connector to set property on.
907  * @path: path to use for property; must not be NULL.
908  *
909  * This creates a property to expose to userspace to specify a
910  * connector path. This is mainly used for DisplayPort MST where
911  * connectors have a topology and we want to allow userspace to give
912  * them more meaningful names.
913  *
914  * Returns:
915  * Zero on success, negative errno on failure.
916  */
917 int drm_mode_connector_set_path_property(struct drm_connector *connector,
918 					 const char *path)
919 {
920 	struct drm_device *dev = connector->dev;
921 	int ret;
922 
923 	ret = drm_property_replace_global_blob(dev,
924 	                                       &connector->path_blob_ptr,
925 	                                       strlen(path) + 1,
926 	                                       path,
927 	                                       &connector->base,
928 	                                       dev->mode_config.path_property);
929 	return ret;
930 }
931 EXPORT_SYMBOL(drm_mode_connector_set_path_property);
932 
933 /**
934  * drm_mode_connector_set_tile_property - set tile property on connector
935  * @connector: connector to set property on.
936  *
937  * This looks up the tile information for a connector, and creates a
938  * property for userspace to parse if it exists. The property is of
939  * the form of 8 integers using ':' as a separator.
940  *
941  * Returns:
942  * Zero on success, errno on failure.
943  */
944 int drm_mode_connector_set_tile_property(struct drm_connector *connector)
945 {
946 	struct drm_device *dev = connector->dev;
947 	char tile[256];
948 	int ret;
949 
950 	if (!connector->has_tile) {
951 		ret  = drm_property_replace_global_blob(dev,
952 		                                        &connector->tile_blob_ptr,
953 		                                        0,
954 		                                        NULL,
955 		                                        &connector->base,
956 		                                        dev->mode_config.tile_property);
957 		return ret;
958 	}
959 
960 	snprintf(tile, 256, "%d:%d:%d:%d:%d:%d:%d:%d",
961 		 connector->tile_group->id, connector->tile_is_single_monitor,
962 		 connector->num_h_tile, connector->num_v_tile,
963 		 connector->tile_h_loc, connector->tile_v_loc,
964 		 connector->tile_h_size, connector->tile_v_size);
965 
966 	ret = drm_property_replace_global_blob(dev,
967 	                                       &connector->tile_blob_ptr,
968 	                                       strlen(tile) + 1,
969 	                                       tile,
970 	                                       &connector->base,
971 	                                       dev->mode_config.tile_property);
972 	return ret;
973 }
974 EXPORT_SYMBOL(drm_mode_connector_set_tile_property);
975 
976 /**
977  * drm_mode_connector_update_edid_property - update the edid property of a connector
978  * @connector: drm connector
979  * @edid: new value of the edid property
980  *
981  * This function creates a new blob modeset object and assigns its id to the
982  * connector's edid property.
983  *
984  * Returns:
985  * Zero on success, negative errno on failure.
986  */
987 int drm_mode_connector_update_edid_property(struct drm_connector *connector,
988 					    const struct edid *edid)
989 {
990 	struct drm_device *dev = connector->dev;
991 	size_t size = 0;
992 	int ret;
993 
994 	/* ignore requests to set edid when overridden */
995 	if (connector->override_edid)
996 		return 0;
997 
998 	if (edid)
999 		size = EDID_LENGTH * (1 + edid->extensions);
1000 
1001 	ret = drm_property_replace_global_blob(dev,
1002 					       &connector->edid_blob_ptr,
1003 	                                       size,
1004 	                                       edid,
1005 	                                       &connector->base,
1006 	                                       dev->mode_config.edid_property);
1007 	return ret;
1008 }
1009 EXPORT_SYMBOL(drm_mode_connector_update_edid_property);
1010 
1011 int drm_mode_connector_set_obj_prop(struct drm_mode_object *obj,
1012 				    struct drm_property *property,
1013 				    uint64_t value)
1014 {
1015 	int ret = -EINVAL;
1016 	struct drm_connector *connector = obj_to_connector(obj);
1017 
1018 	/* Do DPMS ourselves */
1019 	if (property == connector->dev->mode_config.dpms_property) {
1020 		ret = (*connector->funcs->dpms)(connector, (int)value);
1021 	} else if (connector->funcs->set_property)
1022 		ret = connector->funcs->set_property(connector, property, value);
1023 
1024 	/* store the property value if successful */
1025 	if (!ret)
1026 		drm_object_property_set_value(&connector->base, property, value);
1027 	return ret;
1028 }
1029 
1030 int drm_mode_connector_property_set_ioctl(struct drm_device *dev,
1031 				       void *data, struct drm_file *file_priv)
1032 {
1033 	struct drm_mode_connector_set_property *conn_set_prop = data;
1034 	struct drm_mode_obj_set_property obj_set_prop = {
1035 		.value = conn_set_prop->value,
1036 		.prop_id = conn_set_prop->prop_id,
1037 		.obj_id = conn_set_prop->connector_id,
1038 		.obj_type = DRM_MODE_OBJECT_CONNECTOR
1039 	};
1040 
1041 	/* It does all the locking and checking we need */
1042 	return drm_mode_obj_set_property_ioctl(dev, &obj_set_prop, file_priv);
1043 }
1044 
1045 static struct drm_encoder *drm_connector_get_encoder(struct drm_connector *connector)
1046 {
1047 	/* For atomic drivers only state objects are synchronously updated and
1048 	 * protected by modeset locks, so check those first. */
1049 	if (connector->state)
1050 		return connector->state->best_encoder;
1051 	return connector->encoder;
1052 }
1053 
1054 static bool drm_mode_expose_to_userspace(const struct drm_display_mode *mode,
1055 					 const struct drm_file *file_priv)
1056 {
1057 	/*
1058 	 * If user-space hasn't configured the driver to expose the stereo 3D
1059 	 * modes, don't expose them.
1060 	 */
1061 	if (!file_priv->stereo_allowed && drm_mode_is_stereo(mode))
1062 		return false;
1063 
1064 	return true;
1065 }
1066 
1067 int drm_mode_getconnector(struct drm_device *dev, void *data,
1068 			  struct drm_file *file_priv)
1069 {
1070 	struct drm_mode_get_connector *out_resp = data;
1071 	struct drm_connector *connector;
1072 	struct drm_encoder *encoder;
1073 	struct drm_display_mode *mode;
1074 	int mode_count = 0;
1075 	int encoders_count = 0;
1076 	int ret = 0;
1077 	int copied = 0;
1078 	int i;
1079 	struct drm_mode_modeinfo u_mode;
1080 	struct drm_mode_modeinfo __user *mode_ptr;
1081 	uint32_t __user *encoder_ptr;
1082 
1083 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
1084 		return -EINVAL;
1085 
1086 	memset(&u_mode, 0, sizeof(struct drm_mode_modeinfo));
1087 
1088 	mutex_lock(&dev->mode_config.mutex);
1089 
1090 	connector = drm_connector_lookup(dev, out_resp->connector_id);
1091 	if (!connector) {
1092 		ret = -ENOENT;
1093 		goto out_unlock;
1094 	}
1095 
1096 	for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++)
1097 		if (connector->encoder_ids[i] != 0)
1098 			encoders_count++;
1099 
1100 	if (out_resp->count_modes == 0) {
1101 		connector->funcs->fill_modes(connector,
1102 					     dev->mode_config.max_width,
1103 					     dev->mode_config.max_height);
1104 	}
1105 
1106 	/* delayed so we get modes regardless of pre-fill_modes state */
1107 	list_for_each_entry(mode, &connector->modes, head)
1108 		if (drm_mode_expose_to_userspace(mode, file_priv))
1109 			mode_count++;
1110 
1111 	out_resp->connector_id = connector->base.id;
1112 	out_resp->connector_type = connector->connector_type;
1113 	out_resp->connector_type_id = connector->connector_type_id;
1114 	out_resp->mm_width = connector->display_info.width_mm;
1115 	out_resp->mm_height = connector->display_info.height_mm;
1116 	out_resp->subpixel = connector->display_info.subpixel_order;
1117 	out_resp->connection = connector->status;
1118 
1119 	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
1120 	encoder = drm_connector_get_encoder(connector);
1121 	if (encoder)
1122 		out_resp->encoder_id = encoder->base.id;
1123 	else
1124 		out_resp->encoder_id = 0;
1125 
1126 	/*
1127 	 * This ioctl is called twice, once to determine how much space is
1128 	 * needed, and the 2nd time to fill it.
1129 	 */
1130 	if ((out_resp->count_modes >= mode_count) && mode_count) {
1131 		copied = 0;
1132 		mode_ptr = (struct drm_mode_modeinfo __user *)(unsigned long)out_resp->modes_ptr;
1133 		list_for_each_entry(mode, &connector->modes, head) {
1134 			if (!drm_mode_expose_to_userspace(mode, file_priv))
1135 				continue;
1136 
1137 			drm_mode_convert_to_umode(&u_mode, mode);
1138 			if (copy_to_user(mode_ptr + copied,
1139 					 &u_mode, sizeof(u_mode))) {
1140 				ret = -EFAULT;
1141 				goto out;
1142 			}
1143 			copied++;
1144 		}
1145 	}
1146 	out_resp->count_modes = mode_count;
1147 
1148 	ret = drm_mode_object_get_properties(&connector->base, file_priv->atomic,
1149 			(uint32_t __user *)(unsigned long)(out_resp->props_ptr),
1150 			(uint64_t __user *)(unsigned long)(out_resp->prop_values_ptr),
1151 			&out_resp->count_props);
1152 	if (ret)
1153 		goto out;
1154 
1155 	if ((out_resp->count_encoders >= encoders_count) && encoders_count) {
1156 		copied = 0;
1157 		encoder_ptr = (uint32_t __user *)(unsigned long)(out_resp->encoders_ptr);
1158 		for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++) {
1159 			if (connector->encoder_ids[i] != 0) {
1160 				if (put_user(connector->encoder_ids[i],
1161 					     encoder_ptr + copied)) {
1162 					ret = -EFAULT;
1163 					goto out;
1164 				}
1165 				copied++;
1166 			}
1167 		}
1168 	}
1169 	out_resp->count_encoders = encoders_count;
1170 
1171 out:
1172 	drm_modeset_unlock(&dev->mode_config.connection_mutex);
1173 
1174 	drm_connector_unreference(connector);
1175 out_unlock:
1176 	mutex_unlock(&dev->mode_config.mutex);
1177 
1178 	return ret;
1179 }
1180 
1181 
1182 /**
1183  * DOC: Tile group
1184  *
1185  * Tile groups are used to represent tiled monitors with a unique integer
1186  * identifier. Tiled monitors using DisplayID v1.3 have a unique 8-byte handle,
1187  * we store this in a tile group, so we have a common identifier for all tiles
1188  * in a monitor group. The property is called "TILE". Drivers can manage tile
1189  * groups using drm_mode_create_tile_group(), drm_mode_put_tile_group() and
1190  * drm_mode_get_tile_group(). But this is only needed for internal panels where
1191  * the tile group information is exposed through a non-standard way.
1192  */
1193 
1194 static void drm_tile_group_free(struct kref *kref)
1195 {
1196 	struct drm_tile_group *tg = container_of(kref, struct drm_tile_group, refcount);
1197 	struct drm_device *dev = tg->dev;
1198 	mutex_lock(&dev->mode_config.idr_mutex);
1199 	idr_remove(&dev->mode_config.tile_idr, tg->id);
1200 	mutex_unlock(&dev->mode_config.idr_mutex);
1201 	kfree(tg);
1202 }
1203 
1204 /**
1205  * drm_mode_put_tile_group - drop a reference to a tile group.
1206  * @dev: DRM device
1207  * @tg: tile group to drop reference to.
1208  *
1209  * drop reference to tile group and free if 0.
1210  */
1211 void drm_mode_put_tile_group(struct drm_device *dev,
1212 			     struct drm_tile_group *tg)
1213 {
1214 	kref_put(&tg->refcount, drm_tile_group_free);
1215 }
1216 EXPORT_SYMBOL(drm_mode_put_tile_group);
1217 
1218 /**
1219  * drm_mode_get_tile_group - get a reference to an existing tile group
1220  * @dev: DRM device
1221  * @topology: 8-bytes unique per monitor.
1222  *
1223  * Use the unique bytes to get a reference to an existing tile group.
1224  *
1225  * RETURNS:
1226  * tile group or NULL if not found.
1227  */
1228 struct drm_tile_group *drm_mode_get_tile_group(struct drm_device *dev,
1229 					       char topology[8])
1230 {
1231 	struct drm_tile_group *tg;
1232 	int id;
1233 	mutex_lock(&dev->mode_config.idr_mutex);
1234 	idr_for_each_entry(&dev->mode_config.tile_idr, tg, id) {
1235 		if (!memcmp(tg->group_data, topology, 8)) {
1236 			if (!kref_get_unless_zero(&tg->refcount))
1237 				tg = NULL;
1238 			mutex_unlock(&dev->mode_config.idr_mutex);
1239 			return tg;
1240 		}
1241 	}
1242 	mutex_unlock(&dev->mode_config.idr_mutex);
1243 	return NULL;
1244 }
1245 EXPORT_SYMBOL(drm_mode_get_tile_group);
1246 
1247 /**
1248  * drm_mode_create_tile_group - create a tile group from a displayid description
1249  * @dev: DRM device
1250  * @topology: 8-bytes unique per monitor.
1251  *
1252  * Create a tile group for the unique monitor, and get a unique
1253  * identifier for the tile group.
1254  *
1255  * RETURNS:
1256  * new tile group or error.
1257  */
1258 struct drm_tile_group *drm_mode_create_tile_group(struct drm_device *dev,
1259 						  char topology[8])
1260 {
1261 	struct drm_tile_group *tg;
1262 	int ret;
1263 
1264 	tg = kzalloc(sizeof(*tg), GFP_KERNEL);
1265 	if (!tg)
1266 		return ERR_PTR(-ENOMEM);
1267 
1268 	kref_init(&tg->refcount);
1269 	memcpy(tg->group_data, topology, 8);
1270 	tg->dev = dev;
1271 
1272 	mutex_lock(&dev->mode_config.idr_mutex);
1273 	ret = idr_alloc(&dev->mode_config.tile_idr, tg, 1, 0, GFP_KERNEL);
1274 	if (ret >= 0) {
1275 		tg->id = ret;
1276 	} else {
1277 		kfree(tg);
1278 		tg = ERR_PTR(ret);
1279 	}
1280 
1281 	mutex_unlock(&dev->mode_config.idr_mutex);
1282 	return tg;
1283 }
1284 EXPORT_SYMBOL(drm_mode_create_tile_group);
1285