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 <linux/export.h>
24 #include <drm/drmP.h>
25 #include <drm/drm_mode_object.h>
26 #include <drm/drm_atomic.h>
27 
28 #include "drm_crtc_internal.h"
29 
30 /*
31  * Internal function to assign a slot in the object idr and optionally
32  * register the object into the idr.
33  */
34 int __drm_mode_object_add(struct drm_device *dev, struct drm_mode_object *obj,
35 			  uint32_t obj_type, bool register_obj,
36 			  void (*obj_free_cb)(struct kref *kref))
37 {
38 	int ret;
39 
40 	mutex_lock(&dev->mode_config.idr_mutex);
41 	ret = idr_alloc(&dev->mode_config.crtc_idr, register_obj ? obj : NULL, 1, 0, GFP_KERNEL);
42 	if (ret >= 0) {
43 		/*
44 		 * Set up the object linking under the protection of the idr
45 		 * lock so that other users can't see inconsistent state.
46 		 */
47 		obj->id = ret;
48 		obj->type = obj_type;
49 		if (obj_free_cb) {
50 			obj->free_cb = obj_free_cb;
51 			kref_init(&obj->refcount);
52 		}
53 	}
54 	mutex_unlock(&dev->mode_config.idr_mutex);
55 
56 	return ret < 0 ? ret : 0;
57 }
58 
59 /**
60  * drm_mode_object_add - allocate a new modeset identifier
61  * @dev: DRM device
62  * @obj: object pointer, used to generate unique ID
63  * @obj_type: object type
64  *
65  * Create a unique identifier based on @ptr in @dev's identifier space.  Used
66  * for tracking modes, CRTCs and connectors.
67  *
68  * Returns:
69  * Zero on success, error code on failure.
70  */
71 int drm_mode_object_add(struct drm_device *dev,
72 			struct drm_mode_object *obj, uint32_t obj_type)
73 {
74 	return __drm_mode_object_add(dev, obj, obj_type, true, NULL);
75 }
76 
77 void drm_mode_object_register(struct drm_device *dev,
78 			      struct drm_mode_object *obj)
79 {
80 	mutex_lock(&dev->mode_config.idr_mutex);
81 	idr_replace(&dev->mode_config.crtc_idr, obj, obj->id);
82 	mutex_unlock(&dev->mode_config.idr_mutex);
83 }
84 
85 /**
86  * drm_mode_object_unregister - free a modeset identifer
87  * @dev: DRM device
88  * @object: object to free
89  *
90  * Free @id from @dev's unique identifier pool.
91  * This function can be called multiple times, and guards against
92  * multiple removals.
93  * These modeset identifiers are _not_ reference counted. Hence don't use this
94  * for reference counted modeset objects like framebuffers.
95  */
96 void drm_mode_object_unregister(struct drm_device *dev,
97 				struct drm_mode_object *object)
98 {
99 	mutex_lock(&dev->mode_config.idr_mutex);
100 	if (object->id) {
101 		idr_remove(&dev->mode_config.crtc_idr, object->id);
102 		object->id = 0;
103 	}
104 	mutex_unlock(&dev->mode_config.idr_mutex);
105 }
106 
107 /**
108  * drm_lease_required - check types which must be leased to be used
109  * @type: type of object
110  *
111  * Returns whether the provided type of drm_mode_object must
112  * be owned or leased to be used by a process.
113  */
114 bool drm_mode_object_lease_required(uint32_t type)
115 {
116 	switch(type) {
117 	case DRM_MODE_OBJECT_CRTC:
118 	case DRM_MODE_OBJECT_CONNECTOR:
119 	case DRM_MODE_OBJECT_PLANE:
120 		return true;
121 	default:
122 		return false;
123 	}
124 }
125 
126 struct drm_mode_object *__drm_mode_object_find(struct drm_device *dev,
127 					       struct drm_file *file_priv,
128 					       uint32_t id, uint32_t type)
129 {
130 	struct drm_mode_object *obj = NULL;
131 
132 	mutex_lock(&dev->mode_config.idr_mutex);
133 	obj = idr_find(&dev->mode_config.crtc_idr, id);
134 	if (obj && type != DRM_MODE_OBJECT_ANY && obj->type != type)
135 		obj = NULL;
136 	if (obj && obj->id != id)
137 		obj = NULL;
138 
139 	if (obj && drm_mode_object_lease_required(obj->type) &&
140 	    !_drm_lease_held(file_priv, obj->id))
141 		obj = NULL;
142 
143 	if (obj && obj->free_cb) {
144 		if (!kref_get_unless_zero(&obj->refcount))
145 			obj = NULL;
146 	}
147 	mutex_unlock(&dev->mode_config.idr_mutex);
148 
149 	return obj;
150 }
151 
152 /**
153  * drm_mode_object_find - look up a drm object with static lifetime
154  * @dev: drm device
155  * @file_priv: drm file
156  * @id: id of the mode object
157  * @type: type of the mode object
158  *
159  * This function is used to look up a modeset object. It will acquire a
160  * reference for reference counted objects. This reference must be dropped again
161  * by callind drm_mode_object_put().
162  */
163 struct drm_mode_object *drm_mode_object_find(struct drm_device *dev,
164 		struct drm_file *file_priv,
165 		uint32_t id, uint32_t type)
166 {
167 	struct drm_mode_object *obj = NULL;
168 
169 	obj = __drm_mode_object_find(dev, file_priv, id, type);
170 	return obj;
171 }
172 EXPORT_SYMBOL(drm_mode_object_find);
173 
174 /**
175  * drm_mode_object_put - release a mode object reference
176  * @obj: DRM mode object
177  *
178  * This function decrements the object's refcount if it is a refcounted modeset
179  * object. It is a no-op on any other object. This is used to drop references
180  * acquired with drm_mode_object_get().
181  */
182 void drm_mode_object_put(struct drm_mode_object *obj)
183 {
184 	if (obj->free_cb) {
185 		DRM_DEBUG("OBJ ID: %d (%d)\n", obj->id, kref_read(&obj->refcount));
186 		kref_put(&obj->refcount, obj->free_cb);
187 	}
188 }
189 EXPORT_SYMBOL(drm_mode_object_put);
190 
191 /**
192  * drm_mode_object_get - acquire a mode object reference
193  * @obj: DRM mode object
194  *
195  * This function increments the object's refcount if it is a refcounted modeset
196  * object. It is a no-op on any other object. References should be dropped again
197  * by calling drm_mode_object_put().
198  */
199 void drm_mode_object_get(struct drm_mode_object *obj)
200 {
201 	if (obj->free_cb) {
202 		DRM_DEBUG("OBJ ID: %d (%d)\n", obj->id, kref_read(&obj->refcount));
203 		kref_get(&obj->refcount);
204 	}
205 }
206 EXPORT_SYMBOL(drm_mode_object_get);
207 
208 /**
209  * drm_object_attach_property - attach a property to a modeset object
210  * @obj: drm modeset object
211  * @property: property to attach
212  * @init_val: initial value of the property
213  *
214  * This attaches the given property to the modeset object with the given initial
215  * value. Currently this function cannot fail since the properties are stored in
216  * a statically sized array.
217  */
218 void drm_object_attach_property(struct drm_mode_object *obj,
219 				struct drm_property *property,
220 				uint64_t init_val)
221 {
222 	int count = obj->properties->count;
223 
224 	if (count == DRM_OBJECT_MAX_PROPERTY) {
225 		WARN(1, "Failed to attach object property (type: 0x%x). Please "
226 			"increase DRM_OBJECT_MAX_PROPERTY by 1 for each time "
227 			"you see this message on the same object type.\n",
228 			obj->type);
229 		return;
230 	}
231 
232 	obj->properties->properties[count] = property;
233 	obj->properties->values[count] = init_val;
234 	obj->properties->count++;
235 }
236 EXPORT_SYMBOL(drm_object_attach_property);
237 
238 /**
239  * drm_object_property_set_value - set the value of a property
240  * @obj: drm mode object to set property value for
241  * @property: property to set
242  * @val: value the property should be set to
243  *
244  * This function sets a given property on a given object. This function only
245  * changes the software state of the property, it does not call into the
246  * driver's ->set_property callback.
247  *
248  * Note that atomic drivers should not have any need to call this, the core will
249  * ensure consistency of values reported back to userspace through the
250  * appropriate ->atomic_get_property callback. Only legacy drivers should call
251  * this function to update the tracked value (after clamping and other
252  * restrictions have been applied).
253  *
254  * Returns:
255  * Zero on success, error code on failure.
256  */
257 int drm_object_property_set_value(struct drm_mode_object *obj,
258 				  struct drm_property *property, uint64_t val)
259 {
260 	int i;
261 
262 	WARN_ON(drm_drv_uses_atomic_modeset(property->dev) &&
263 		!(property->flags & DRM_MODE_PROP_IMMUTABLE));
264 
265 	for (i = 0; i < obj->properties->count; i++) {
266 		if (obj->properties->properties[i] == property) {
267 			obj->properties->values[i] = val;
268 			return 0;
269 		}
270 	}
271 
272 	return -EINVAL;
273 }
274 EXPORT_SYMBOL(drm_object_property_set_value);
275 
276 static int __drm_object_property_get_value(struct drm_mode_object *obj,
277 					   struct drm_property *property,
278 					   uint64_t *val)
279 {
280 	int i;
281 
282 	/* read-only properties bypass atomic mechanism and still store
283 	 * their value in obj->properties->values[].. mostly to avoid
284 	 * having to deal w/ EDID and similar props in atomic paths:
285 	 */
286 	if (drm_drv_uses_atomic_modeset(property->dev) &&
287 			!(property->flags & DRM_MODE_PROP_IMMUTABLE))
288 		return drm_atomic_get_property(obj, property, val);
289 
290 	for (i = 0; i < obj->properties->count; i++) {
291 		if (obj->properties->properties[i] == property) {
292 			*val = obj->properties->values[i];
293 			return 0;
294 		}
295 
296 	}
297 
298 	return -EINVAL;
299 }
300 
301 /**
302  * drm_object_property_get_value - retrieve the value of a property
303  * @obj: drm mode object to get property value from
304  * @property: property to retrieve
305  * @val: storage for the property value
306  *
307  * This function retrieves the softare state of the given property for the given
308  * property. Since there is no driver callback to retrieve the current property
309  * value this might be out of sync with the hardware, depending upon the driver
310  * and property.
311  *
312  * Atomic drivers should never call this function directly, the core will read
313  * out property values through the various ->atomic_get_property callbacks.
314  *
315  * Returns:
316  * Zero on success, error code on failure.
317  */
318 int drm_object_property_get_value(struct drm_mode_object *obj,
319 				  struct drm_property *property, uint64_t *val)
320 {
321 	WARN_ON(drm_drv_uses_atomic_modeset(property->dev));
322 
323 	return __drm_object_property_get_value(obj, property, val);
324 }
325 EXPORT_SYMBOL(drm_object_property_get_value);
326 
327 /* helper for getconnector and getproperties ioctls */
328 int drm_mode_object_get_properties(struct drm_mode_object *obj, bool atomic,
329 				   uint32_t __user *prop_ptr,
330 				   uint64_t __user *prop_values,
331 				   uint32_t *arg_count_props)
332 {
333 	int i, ret, count;
334 
335 	for (i = 0, count = 0; i < obj->properties->count; i++) {
336 		struct drm_property *prop = obj->properties->properties[i];
337 		uint64_t val;
338 
339 		if ((prop->flags & DRM_MODE_PROP_ATOMIC) && !atomic)
340 			continue;
341 
342 		if (*arg_count_props > count) {
343 			ret = __drm_object_property_get_value(obj, prop, &val);
344 			if (ret)
345 				return ret;
346 
347 			if (put_user(prop->base.id, prop_ptr + count))
348 				return -EFAULT;
349 
350 			if (put_user(val, prop_values + count))
351 				return -EFAULT;
352 		}
353 
354 		count++;
355 	}
356 	*arg_count_props = count;
357 
358 	return 0;
359 }
360 
361 /**
362  * drm_mode_obj_get_properties_ioctl - get the current value of a object's property
363  * @dev: DRM device
364  * @data: ioctl data
365  * @file_priv: DRM file info
366  *
367  * This function retrieves the current value for an object's property. Compared
368  * to the connector specific ioctl this one is extended to also work on crtc and
369  * plane objects.
370  *
371  * Called by the user via ioctl.
372  *
373  * Returns:
374  * Zero on success, negative errno on failure.
375  */
376 int drm_mode_obj_get_properties_ioctl(struct drm_device *dev, void *data,
377 				      struct drm_file *file_priv)
378 {
379 	struct drm_mode_obj_get_properties *arg = data;
380 	struct drm_mode_object *obj;
381 	int ret = 0;
382 
383 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
384 		return -EINVAL;
385 
386 	drm_modeset_lock_all(dev);
387 
388 	obj = drm_mode_object_find(dev, file_priv, arg->obj_id, arg->obj_type);
389 	if (!obj) {
390 		ret = -ENOENT;
391 		goto out;
392 	}
393 	if (!obj->properties) {
394 		ret = -EINVAL;
395 		goto out_unref;
396 	}
397 
398 	ret = drm_mode_object_get_properties(obj, file_priv->atomic,
399 			(uint32_t __user *)(unsigned long)(arg->props_ptr),
400 			(uint64_t __user *)(unsigned long)(arg->prop_values_ptr),
401 			&arg->count_props);
402 
403 out_unref:
404 	drm_mode_object_put(obj);
405 out:
406 	drm_modeset_unlock_all(dev);
407 	return ret;
408 }
409 
410 struct drm_property *drm_mode_obj_find_prop_id(struct drm_mode_object *obj,
411 					       uint32_t prop_id)
412 {
413 	int i;
414 
415 	for (i = 0; i < obj->properties->count; i++)
416 		if (obj->properties->properties[i]->base.id == prop_id)
417 			return obj->properties->properties[i];
418 
419 	return NULL;
420 }
421 
422 static int set_property_legacy(struct drm_mode_object *obj,
423 			       struct drm_property *prop,
424 			       uint64_t prop_value)
425 {
426 	struct drm_device *dev = prop->dev;
427 	struct drm_mode_object *ref;
428 	int ret = -EINVAL;
429 
430 	if (!drm_property_change_valid_get(prop, prop_value, &ref))
431 		return -EINVAL;
432 
433 	drm_modeset_lock_all(dev);
434 	switch (obj->type) {
435 	case DRM_MODE_OBJECT_CONNECTOR:
436 		ret = drm_mode_connector_set_obj_prop(obj, prop,
437 						      prop_value);
438 		break;
439 	case DRM_MODE_OBJECT_CRTC:
440 		ret = drm_mode_crtc_set_obj_prop(obj, prop, prop_value);
441 		break;
442 	case DRM_MODE_OBJECT_PLANE:
443 		ret = drm_mode_plane_set_obj_prop(obj_to_plane(obj),
444 						  prop, prop_value);
445 		break;
446 	}
447 	drm_property_change_valid_put(prop, ref);
448 	drm_modeset_unlock_all(dev);
449 
450 	return ret;
451 }
452 
453 static int set_property_atomic(struct drm_mode_object *obj,
454 			       struct drm_property *prop,
455 			       uint64_t prop_value)
456 {
457 	struct drm_device *dev = prop->dev;
458 	struct drm_atomic_state *state;
459 	struct drm_modeset_acquire_ctx ctx;
460 	int ret;
461 
462 	drm_modeset_acquire_init(&ctx, 0);
463 
464 	state = drm_atomic_state_alloc(dev);
465 	if (!state)
466 		return -ENOMEM;
467 	state->acquire_ctx = &ctx;
468 retry:
469 	if (prop == state->dev->mode_config.dpms_property) {
470 		if (obj->type != DRM_MODE_OBJECT_CONNECTOR) {
471 			ret = -EINVAL;
472 			goto out;
473 		}
474 
475 		ret = drm_atomic_connector_commit_dpms(state,
476 						       obj_to_connector(obj),
477 						       prop_value);
478 	} else {
479 		ret = drm_atomic_set_property(state, obj, prop, prop_value);
480 		if (ret)
481 			goto out;
482 		ret = drm_atomic_commit(state);
483 	}
484 out:
485 	if (ret == -EDEADLK) {
486 		drm_atomic_state_clear(state);
487 		drm_modeset_backoff(&ctx);
488 		goto retry;
489 	}
490 
491 	drm_atomic_state_put(state);
492 
493 	drm_modeset_drop_locks(&ctx);
494 	drm_modeset_acquire_fini(&ctx);
495 
496 	return ret;
497 }
498 
499 int drm_mode_obj_set_property_ioctl(struct drm_device *dev, void *data,
500 				    struct drm_file *file_priv)
501 {
502 	struct drm_mode_obj_set_property *arg = data;
503 	struct drm_mode_object *arg_obj;
504 	struct drm_property *property;
505 	int ret = -EINVAL;
506 
507 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
508 		return -EINVAL;
509 
510 	arg_obj = drm_mode_object_find(dev, file_priv, arg->obj_id, arg->obj_type);
511 	if (!arg_obj)
512 		return -ENOENT;
513 
514 	if (!arg_obj->properties)
515 		goto out_unref;
516 
517 	property = drm_mode_obj_find_prop_id(arg_obj, arg->prop_id);
518 	if (!property)
519 		goto out_unref;
520 
521 	if (drm_drv_uses_atomic_modeset(property->dev))
522 		ret = set_property_atomic(arg_obj, property, arg->value);
523 	else
524 		ret = set_property_legacy(arg_obj, property, arg->value);
525 
526 out_unref:
527 	drm_mode_object_put(arg_obj);
528 	return ret;
529 }
530