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 struct drm_mode_object *__drm_mode_object_find(struct drm_device *dev,
108 					       uint32_t id, uint32_t type)
109 {
110 	struct drm_mode_object *obj = NULL;
111 
112 	mutex_lock(&dev->mode_config.idr_mutex);
113 	obj = idr_find(&dev->mode_config.crtc_idr, id);
114 	if (obj && type != DRM_MODE_OBJECT_ANY && obj->type != type)
115 		obj = NULL;
116 	if (obj && obj->id != id)
117 		obj = NULL;
118 
119 	if (obj && obj->free_cb) {
120 		if (!kref_get_unless_zero(&obj->refcount))
121 			obj = NULL;
122 	}
123 	mutex_unlock(&dev->mode_config.idr_mutex);
124 
125 	return obj;
126 }
127 
128 /**
129  * drm_mode_object_find - look up a drm object with static lifetime
130  * @dev: drm device
131  * @id: id of the mode object
132  * @type: type of the mode object
133  *
134  * This function is used to look up a modeset object. It will acquire a
135  * reference for reference counted objects. This reference must be dropped again
136  * by callind drm_mode_object_put().
137  */
138 struct drm_mode_object *drm_mode_object_find(struct drm_device *dev,
139 		uint32_t id, uint32_t type)
140 {
141 	struct drm_mode_object *obj = NULL;
142 
143 	obj = __drm_mode_object_find(dev, id, type);
144 	return obj;
145 }
146 EXPORT_SYMBOL(drm_mode_object_find);
147 
148 /**
149  * drm_mode_object_put - release a mode object reference
150  * @obj: DRM mode object
151  *
152  * This function decrements the object's refcount if it is a refcounted modeset
153  * object. It is a no-op on any other object. This is used to drop references
154  * acquired with drm_mode_object_get().
155  */
156 void drm_mode_object_put(struct drm_mode_object *obj)
157 {
158 	if (obj->free_cb) {
159 		DRM_DEBUG("OBJ ID: %d (%d)\n", obj->id, kref_read(&obj->refcount));
160 		kref_put(&obj->refcount, obj->free_cb);
161 	}
162 }
163 EXPORT_SYMBOL(drm_mode_object_put);
164 
165 /**
166  * drm_mode_object_get - acquire a mode object reference
167  * @obj: DRM mode object
168  *
169  * This function increments the object's refcount if it is a refcounted modeset
170  * object. It is a no-op on any other object. References should be dropped again
171  * by calling drm_mode_object_put().
172  */
173 void drm_mode_object_get(struct drm_mode_object *obj)
174 {
175 	if (obj->free_cb) {
176 		DRM_DEBUG("OBJ ID: %d (%d)\n", obj->id, kref_read(&obj->refcount));
177 		kref_get(&obj->refcount);
178 	}
179 }
180 EXPORT_SYMBOL(drm_mode_object_get);
181 
182 /**
183  * drm_object_attach_property - attach a property to a modeset object
184  * @obj: drm modeset object
185  * @property: property to attach
186  * @init_val: initial value of the property
187  *
188  * This attaches the given property to the modeset object with the given initial
189  * value. Currently this function cannot fail since the properties are stored in
190  * a statically sized array.
191  */
192 void drm_object_attach_property(struct drm_mode_object *obj,
193 				struct drm_property *property,
194 				uint64_t init_val)
195 {
196 	int count = obj->properties->count;
197 
198 	if (count == DRM_OBJECT_MAX_PROPERTY) {
199 		WARN(1, "Failed to attach object property (type: 0x%x). Please "
200 			"increase DRM_OBJECT_MAX_PROPERTY by 1 for each time "
201 			"you see this message on the same object type.\n",
202 			obj->type);
203 		return;
204 	}
205 
206 	obj->properties->properties[count] = property;
207 	obj->properties->values[count] = init_val;
208 	obj->properties->count++;
209 }
210 EXPORT_SYMBOL(drm_object_attach_property);
211 
212 /**
213  * drm_object_property_set_value - set the value of a property
214  * @obj: drm mode object to set property value for
215  * @property: property to set
216  * @val: value the property should be set to
217  *
218  * This function sets a given property on a given object. This function only
219  * changes the software state of the property, it does not call into the
220  * driver's ->set_property callback.
221  *
222  * Note that atomic drivers should not have any need to call this, the core will
223  * ensure consistency of values reported back to userspace through the
224  * appropriate ->atomic_get_property callback. Only legacy drivers should call
225  * this function to update the tracked value (after clamping and other
226  * restrictions have been applied).
227  *
228  * Returns:
229  * Zero on success, error code on failure.
230  */
231 int drm_object_property_set_value(struct drm_mode_object *obj,
232 				  struct drm_property *property, uint64_t val)
233 {
234 	int i;
235 
236 	WARN_ON(drm_drv_uses_atomic_modeset(property->dev) &&
237 		!(property->flags & DRM_MODE_PROP_IMMUTABLE));
238 
239 	for (i = 0; i < obj->properties->count; i++) {
240 		if (obj->properties->properties[i] == property) {
241 			obj->properties->values[i] = val;
242 			return 0;
243 		}
244 	}
245 
246 	return -EINVAL;
247 }
248 EXPORT_SYMBOL(drm_object_property_set_value);
249 
250 int __drm_object_property_get_value(struct drm_mode_object *obj,
251 				  struct drm_property *property, uint64_t *val)
252 {
253 	int i;
254 
255 	/* read-only properties bypass atomic mechanism and still store
256 	 * their value in obj->properties->values[].. mostly to avoid
257 	 * having to deal w/ EDID and similar props in atomic paths:
258 	 */
259 	if (drm_drv_uses_atomic_modeset(property->dev) &&
260 			!(property->flags & DRM_MODE_PROP_IMMUTABLE))
261 		return drm_atomic_get_property(obj, property, val);
262 
263 	for (i = 0; i < obj->properties->count; i++) {
264 		if (obj->properties->properties[i] == property) {
265 			*val = obj->properties->values[i];
266 			return 0;
267 		}
268 
269 	}
270 
271 	return -EINVAL;
272 }
273 
274 /**
275  * drm_object_property_get_value - retrieve the value of a property
276  * @obj: drm mode object to get property value from
277  * @property: property to retrieve
278  * @val: storage for the property value
279  *
280  * This function retrieves the softare state of the given property for the given
281  * property. Since there is no driver callback to retrieve the current property
282  * value this might be out of sync with the hardware, depending upon the driver
283  * and property.
284  *
285  * Atomic drivers should never call this function directly, the core will read
286  * out property values through the various ->atomic_get_property callbacks.
287  *
288  * Returns:
289  * Zero on success, error code on failure.
290  */
291 int drm_object_property_get_value(struct drm_mode_object *obj,
292 				  struct drm_property *property, uint64_t *val)
293 {
294 	WARN_ON(drm_drv_uses_atomic_modeset(property->dev));
295 
296 	return __drm_object_property_get_value(obj, property, val);
297 }
298 EXPORT_SYMBOL(drm_object_property_get_value);
299 
300 /* helper for getconnector and getproperties ioctls */
301 int drm_mode_object_get_properties(struct drm_mode_object *obj, bool atomic,
302 				   uint32_t __user *prop_ptr,
303 				   uint64_t __user *prop_values,
304 				   uint32_t *arg_count_props)
305 {
306 	int i, ret, count;
307 
308 	for (i = 0, count = 0; i < obj->properties->count; i++) {
309 		struct drm_property *prop = obj->properties->properties[i];
310 		uint64_t val;
311 
312 		if ((prop->flags & DRM_MODE_PROP_ATOMIC) && !atomic)
313 			continue;
314 
315 		if (*arg_count_props > count) {
316 			ret = __drm_object_property_get_value(obj, prop, &val);
317 			if (ret)
318 				return ret;
319 
320 			if (put_user(prop->base.id, prop_ptr + count))
321 				return -EFAULT;
322 
323 			if (put_user(val, prop_values + count))
324 				return -EFAULT;
325 		}
326 
327 		count++;
328 	}
329 	*arg_count_props = count;
330 
331 	return 0;
332 }
333 
334 /**
335  * drm_mode_obj_get_properties_ioctl - get the current value of a object's property
336  * @dev: DRM device
337  * @data: ioctl data
338  * @file_priv: DRM file info
339  *
340  * This function retrieves the current value for an object's property. Compared
341  * to the connector specific ioctl this one is extended to also work on crtc and
342  * plane objects.
343  *
344  * Called by the user via ioctl.
345  *
346  * Returns:
347  * Zero on success, negative errno on failure.
348  */
349 int drm_mode_obj_get_properties_ioctl(struct drm_device *dev, void *data,
350 				      struct drm_file *file_priv)
351 {
352 	struct drm_mode_obj_get_properties *arg = data;
353 	struct drm_mode_object *obj;
354 	int ret = 0;
355 
356 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
357 		return -EINVAL;
358 
359 	drm_modeset_lock_all(dev);
360 
361 	obj = drm_mode_object_find(dev, arg->obj_id, arg->obj_type);
362 	if (!obj) {
363 		ret = -ENOENT;
364 		goto out;
365 	}
366 	if (!obj->properties) {
367 		ret = -EINVAL;
368 		goto out_unref;
369 	}
370 
371 	ret = drm_mode_object_get_properties(obj, file_priv->atomic,
372 			(uint32_t __user *)(unsigned long)(arg->props_ptr),
373 			(uint64_t __user *)(unsigned long)(arg->prop_values_ptr),
374 			&arg->count_props);
375 
376 out_unref:
377 	drm_mode_object_put(obj);
378 out:
379 	drm_modeset_unlock_all(dev);
380 	return ret;
381 }
382 
383 struct drm_property *drm_mode_obj_find_prop_id(struct drm_mode_object *obj,
384 					       uint32_t prop_id)
385 {
386 	int i;
387 
388 	for (i = 0; i < obj->properties->count; i++)
389 		if (obj->properties->properties[i]->base.id == prop_id)
390 			return obj->properties->properties[i];
391 
392 	return NULL;
393 }
394 
395 static int set_property_legacy(struct drm_mode_object *obj,
396 			       struct drm_property *prop,
397 			       uint64_t prop_value)
398 {
399 	struct drm_device *dev = prop->dev;
400 	struct drm_mode_object *ref;
401 	int ret = -EINVAL;
402 
403 	if (!drm_property_change_valid_get(prop, prop_value, &ref))
404 		return -EINVAL;
405 
406 	drm_modeset_lock_all(dev);
407 	switch (obj->type) {
408 	case DRM_MODE_OBJECT_CONNECTOR:
409 		ret = drm_mode_connector_set_obj_prop(obj, prop,
410 						      prop_value);
411 		break;
412 	case DRM_MODE_OBJECT_CRTC:
413 		ret = drm_mode_crtc_set_obj_prop(obj, prop, prop_value);
414 		break;
415 	case DRM_MODE_OBJECT_PLANE:
416 		ret = drm_mode_plane_set_obj_prop(obj_to_plane(obj),
417 						  prop, prop_value);
418 		break;
419 	}
420 	drm_property_change_valid_put(prop, ref);
421 	drm_modeset_unlock_all(dev);
422 
423 	return ret;
424 }
425 
426 static int set_property_atomic(struct drm_mode_object *obj,
427 			       struct drm_property *prop,
428 			       uint64_t prop_value)
429 {
430 	struct drm_device *dev = prop->dev;
431 	struct drm_atomic_state *state;
432 	struct drm_modeset_acquire_ctx ctx;
433 	int ret;
434 
435 	drm_modeset_acquire_init(&ctx, 0);
436 
437 	state = drm_atomic_state_alloc(dev);
438 	if (!state)
439 		return -ENOMEM;
440 	state->acquire_ctx = &ctx;
441 retry:
442 	if (prop == state->dev->mode_config.dpms_property) {
443 		if (obj->type != DRM_MODE_OBJECT_CONNECTOR) {
444 			ret = -EINVAL;
445 			goto out;
446 		}
447 
448 		ret = drm_atomic_connector_commit_dpms(state,
449 						       obj_to_connector(obj),
450 						       prop_value);
451 	} else {
452 		ret = drm_atomic_set_property(state, obj, prop, prop_value);
453 		if (ret)
454 			goto out;
455 		ret = drm_atomic_commit(state);
456 	}
457 out:
458 	if (ret == -EDEADLK) {
459 		drm_atomic_state_clear(state);
460 		drm_modeset_backoff(&ctx);
461 		goto retry;
462 	}
463 
464 	drm_atomic_state_put(state);
465 
466 	drm_modeset_drop_locks(&ctx);
467 	drm_modeset_acquire_fini(&ctx);
468 
469 	return ret;
470 }
471 
472 int drm_mode_obj_set_property_ioctl(struct drm_device *dev, void *data,
473 				    struct drm_file *file_priv)
474 {
475 	struct drm_mode_obj_set_property *arg = data;
476 	struct drm_mode_object *arg_obj;
477 	struct drm_property *property;
478 	int ret = -EINVAL;
479 
480 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
481 		return -EINVAL;
482 
483 	arg_obj = drm_mode_object_find(dev, arg->obj_id, arg->obj_type);
484 	if (!arg_obj)
485 		return -ENOENT;
486 
487 	if (!arg_obj->properties)
488 		goto out_unref;
489 
490 	property = drm_mode_obj_find_prop_id(arg_obj, arg->prop_id);
491 	if (!property)
492 		goto out_unref;
493 
494 	if (drm_drv_uses_atomic_modeset(property->dev))
495 		ret = set_property_atomic(arg_obj, property, arg->value);
496 	else
497 		ret = set_property_legacy(arg_obj, property, arg->value);
498 
499 out_unref:
500 	drm_mode_object_put(arg_obj);
501 	return ret;
502 }
503