xref: /linux/drivers/gpu/drm/drm_mode_object.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
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_get_reg(struct drm_device *dev,
35 			    struct drm_mode_object *obj,
36 			    uint32_t obj_type,
37 			    bool register_obj,
38 			    void (*obj_free_cb)(struct kref *kref))
39 {
40 	int ret;
41 
42 	mutex_lock(&dev->mode_config.idr_mutex);
43 	ret = idr_alloc(&dev->mode_config.crtc_idr, register_obj ? obj : NULL, 1, 0, GFP_KERNEL);
44 	if (ret >= 0) {
45 		/*
46 		 * Set up the object linking under the protection of the idr
47 		 * lock so that other users can't see inconsistent state.
48 		 */
49 		obj->id = ret;
50 		obj->type = obj_type;
51 		if (obj_free_cb) {
52 			obj->free_cb = obj_free_cb;
53 			kref_init(&obj->refcount);
54 		}
55 	}
56 	mutex_unlock(&dev->mode_config.idr_mutex);
57 
58 	return ret < 0 ? ret : 0;
59 }
60 
61 /**
62  * drm_mode_object_get - allocate a new modeset identifier
63  * @dev: DRM device
64  * @obj: object pointer, used to generate unique ID
65  * @obj_type: object type
66  *
67  * Create a unique identifier based on @ptr in @dev's identifier space.  Used
68  * for tracking modes, CRTCs and connectors. Note that despite the _get postfix
69  * modeset identifiers are _not_ reference counted. Hence don't use this for
70  * reference counted modeset objects like framebuffers.
71  *
72  * Returns:
73  * Zero on success, error code on failure.
74  */
75 int drm_mode_object_get(struct drm_device *dev,
76 			struct drm_mode_object *obj, uint32_t obj_type)
77 {
78 	return drm_mode_object_get_reg(dev, obj, obj_type, true, NULL);
79 }
80 
81 void drm_mode_object_register(struct drm_device *dev,
82 			      struct drm_mode_object *obj)
83 {
84 	mutex_lock(&dev->mode_config.idr_mutex);
85 	idr_replace(&dev->mode_config.crtc_idr, obj, obj->id);
86 	mutex_unlock(&dev->mode_config.idr_mutex);
87 }
88 
89 /**
90  * drm_mode_object_unregister - free a modeset identifer
91  * @dev: DRM device
92  * @object: object to free
93  *
94  * Free @id from @dev's unique identifier pool.
95  * This function can be called multiple times, and guards against
96  * multiple removals.
97  * These modeset identifiers are _not_ reference counted. Hence don't use this
98  * for reference counted modeset objects like framebuffers.
99  */
100 void drm_mode_object_unregister(struct drm_device *dev,
101 				struct drm_mode_object *object)
102 {
103 	mutex_lock(&dev->mode_config.idr_mutex);
104 	if (object->id) {
105 		idr_remove(&dev->mode_config.crtc_idr, object->id);
106 		object->id = 0;
107 	}
108 	mutex_unlock(&dev->mode_config.idr_mutex);
109 }
110 
111 struct drm_mode_object *__drm_mode_object_find(struct drm_device *dev,
112 					       uint32_t id, uint32_t type)
113 {
114 	struct drm_mode_object *obj = NULL;
115 
116 	mutex_lock(&dev->mode_config.idr_mutex);
117 	obj = idr_find(&dev->mode_config.crtc_idr, id);
118 	if (obj && type != DRM_MODE_OBJECT_ANY && obj->type != type)
119 		obj = NULL;
120 	if (obj && obj->id != id)
121 		obj = NULL;
122 
123 	if (obj && obj->free_cb) {
124 		if (!kref_get_unless_zero(&obj->refcount))
125 			obj = NULL;
126 	}
127 	mutex_unlock(&dev->mode_config.idr_mutex);
128 
129 	return obj;
130 }
131 
132 /**
133  * drm_mode_object_find - look up a drm object with static lifetime
134  * @dev: drm device
135  * @id: id of the mode object
136  * @type: type of the mode object
137  *
138  * This function is used to look up a modeset object. It will acquire a
139  * reference for reference counted objects. This reference must be dropped again
140  * by callind drm_mode_object_unreference().
141  */
142 struct drm_mode_object *drm_mode_object_find(struct drm_device *dev,
143 		uint32_t id, uint32_t type)
144 {
145 	struct drm_mode_object *obj = NULL;
146 
147 	obj = __drm_mode_object_find(dev, id, type);
148 	return obj;
149 }
150 EXPORT_SYMBOL(drm_mode_object_find);
151 
152 /**
153  * drm_mode_object_unreference - decr the object refcnt
154  * @obj: mode_object
155  *
156  * This function decrements the object's refcount if it is a refcounted modeset
157  * object. It is a no-op on any other object. This is used to drop references
158  * acquired with drm_mode_object_reference().
159  */
160 void drm_mode_object_unreference(struct drm_mode_object *obj)
161 {
162 	if (obj->free_cb) {
163 		DRM_DEBUG("OBJ ID: %d (%d)\n", obj->id, kref_read(&obj->refcount));
164 		kref_put(&obj->refcount, obj->free_cb);
165 	}
166 }
167 EXPORT_SYMBOL(drm_mode_object_unreference);
168 
169 /**
170  * drm_mode_object_reference - incr the object refcnt
171  * @obj: mode_object
172  *
173  * This function increments the object's refcount if it is a refcounted modeset
174  * object. It is a no-op on any other object. References should be dropped again
175  * by calling drm_mode_object_unreference().
176  */
177 void drm_mode_object_reference(struct drm_mode_object *obj)
178 {
179 	if (obj->free_cb) {
180 		DRM_DEBUG("OBJ ID: %d (%d)\n", obj->id, kref_read(&obj->refcount));
181 		kref_get(&obj->refcount);
182 	}
183 }
184 EXPORT_SYMBOL(drm_mode_object_reference);
185 
186 /**
187  * drm_object_attach_property - attach a property to a modeset object
188  * @obj: drm modeset object
189  * @property: property to attach
190  * @init_val: initial value of the property
191  *
192  * This attaches the given property to the modeset object with the given initial
193  * value. Currently this function cannot fail since the properties are stored in
194  * a statically sized array.
195  */
196 void drm_object_attach_property(struct drm_mode_object *obj,
197 				struct drm_property *property,
198 				uint64_t init_val)
199 {
200 	int count = obj->properties->count;
201 
202 	if (count == DRM_OBJECT_MAX_PROPERTY) {
203 		WARN(1, "Failed to attach object property (type: 0x%x). Please "
204 			"increase DRM_OBJECT_MAX_PROPERTY by 1 for each time "
205 			"you see this message on the same object type.\n",
206 			obj->type);
207 		return;
208 	}
209 
210 	obj->properties->properties[count] = property;
211 	obj->properties->values[count] = init_val;
212 	obj->properties->count++;
213 }
214 EXPORT_SYMBOL(drm_object_attach_property);
215 
216 /**
217  * drm_object_property_set_value - set the value of a property
218  * @obj: drm mode object to set property value for
219  * @property: property to set
220  * @val: value the property should be set to
221  *
222  * This function sets a given property on a given object. This function only
223  * changes the software state of the property, it does not call into the
224  * driver's ->set_property callback.
225  *
226  * Note that atomic drivers should not have any need to call this, the core will
227  * ensure consistency of values reported back to userspace through the
228  * appropriate ->atomic_get_property callback. Only legacy drivers should call
229  * this function to update the tracked value (after clamping and other
230  * restrictions have been applied).
231  *
232  * Returns:
233  * Zero on success, error code on failure.
234  */
235 int drm_object_property_set_value(struct drm_mode_object *obj,
236 				  struct drm_property *property, uint64_t val)
237 {
238 	int i;
239 
240 	for (i = 0; i < obj->properties->count; i++) {
241 		if (obj->properties->properties[i] == property) {
242 			obj->properties->values[i] = val;
243 			return 0;
244 		}
245 	}
246 
247 	return -EINVAL;
248 }
249 EXPORT_SYMBOL(drm_object_property_set_value);
250 
251 /**
252  * drm_object_property_get_value - retrieve the value of a property
253  * @obj: drm mode object to get property value from
254  * @property: property to retrieve
255  * @val: storage for the property value
256  *
257  * This function retrieves the softare state of the given property for the given
258  * property. Since there is no driver callback to retrieve the current property
259  * value this might be out of sync with the hardware, depending upon the driver
260  * and property.
261  *
262  * Atomic drivers should never call this function directly, the core will read
263  * out property values through the various ->atomic_get_property callbacks.
264  *
265  * Returns:
266  * Zero on success, error code on failure.
267  */
268 int drm_object_property_get_value(struct drm_mode_object *obj,
269 				  struct drm_property *property, uint64_t *val)
270 {
271 	int i;
272 
273 	/* read-only properties bypass atomic mechanism and still store
274 	 * their value in obj->properties->values[].. mostly to avoid
275 	 * having to deal w/ EDID and similar props in atomic paths:
276 	 */
277 	if (drm_drv_uses_atomic_modeset(property->dev) &&
278 			!(property->flags & DRM_MODE_PROP_IMMUTABLE))
279 		return drm_atomic_get_property(obj, property, val);
280 
281 	for (i = 0; i < obj->properties->count; i++) {
282 		if (obj->properties->properties[i] == property) {
283 			*val = obj->properties->values[i];
284 			return 0;
285 		}
286 
287 	}
288 
289 	return -EINVAL;
290 }
291 EXPORT_SYMBOL(drm_object_property_get_value);
292 
293 /* helper for getconnector and getproperties ioctls */
294 int drm_mode_object_get_properties(struct drm_mode_object *obj, bool atomic,
295 				   uint32_t __user *prop_ptr,
296 				   uint64_t __user *prop_values,
297 				   uint32_t *arg_count_props)
298 {
299 	int i, ret, count;
300 
301 	for (i = 0, count = 0; i < obj->properties->count; i++) {
302 		struct drm_property *prop = obj->properties->properties[i];
303 		uint64_t val;
304 
305 		if ((prop->flags & DRM_MODE_PROP_ATOMIC) && !atomic)
306 			continue;
307 
308 		if (*arg_count_props > count) {
309 			ret = drm_object_property_get_value(obj, prop, &val);
310 			if (ret)
311 				return ret;
312 
313 			if (put_user(prop->base.id, prop_ptr + count))
314 				return -EFAULT;
315 
316 			if (put_user(val, prop_values + count))
317 				return -EFAULT;
318 		}
319 
320 		count++;
321 	}
322 	*arg_count_props = count;
323 
324 	return 0;
325 }
326 
327 /**
328  * drm_mode_obj_get_properties_ioctl - get the current value of a object's property
329  * @dev: DRM device
330  * @data: ioctl data
331  * @file_priv: DRM file info
332  *
333  * This function retrieves the current value for an object's property. Compared
334  * to the connector specific ioctl this one is extended to also work on crtc and
335  * plane objects.
336  *
337  * Called by the user via ioctl.
338  *
339  * Returns:
340  * Zero on success, negative errno on failure.
341  */
342 int drm_mode_obj_get_properties_ioctl(struct drm_device *dev, void *data,
343 				      struct drm_file *file_priv)
344 {
345 	struct drm_mode_obj_get_properties *arg = data;
346 	struct drm_mode_object *obj;
347 	int ret = 0;
348 
349 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
350 		return -EINVAL;
351 
352 	drm_modeset_lock_all(dev);
353 
354 	obj = drm_mode_object_find(dev, arg->obj_id, arg->obj_type);
355 	if (!obj) {
356 		ret = -ENOENT;
357 		goto out;
358 	}
359 	if (!obj->properties) {
360 		ret = -EINVAL;
361 		goto out_unref;
362 	}
363 
364 	ret = drm_mode_object_get_properties(obj, file_priv->atomic,
365 			(uint32_t __user *)(unsigned long)(arg->props_ptr),
366 			(uint64_t __user *)(unsigned long)(arg->prop_values_ptr),
367 			&arg->count_props);
368 
369 out_unref:
370 	drm_mode_object_unreference(obj);
371 out:
372 	drm_modeset_unlock_all(dev);
373 	return ret;
374 }
375 
376 struct drm_property *drm_mode_obj_find_prop_id(struct drm_mode_object *obj,
377 					       uint32_t prop_id)
378 {
379 	int i;
380 
381 	for (i = 0; i < obj->properties->count; i++)
382 		if (obj->properties->properties[i]->base.id == prop_id)
383 			return obj->properties->properties[i];
384 
385 	return NULL;
386 }
387 
388 int drm_mode_obj_set_property_ioctl(struct drm_device *dev, void *data,
389 				    struct drm_file *file_priv)
390 {
391 	struct drm_mode_obj_set_property *arg = data;
392 	struct drm_mode_object *arg_obj;
393 	struct drm_property *property;
394 	int ret = -EINVAL;
395 	struct drm_mode_object *ref;
396 
397 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
398 		return -EINVAL;
399 
400 	drm_modeset_lock_all(dev);
401 
402 	arg_obj = drm_mode_object_find(dev, arg->obj_id, arg->obj_type);
403 	if (!arg_obj) {
404 		ret = -ENOENT;
405 		goto out;
406 	}
407 
408 	if (!arg_obj->properties)
409 		goto out_unref;
410 
411 	property = drm_mode_obj_find_prop_id(arg_obj, arg->prop_id);
412 	if (!property)
413 		goto out_unref;
414 
415 	if (!drm_property_change_valid_get(property, arg->value, &ref))
416 		goto out_unref;
417 
418 	switch (arg_obj->type) {
419 	case DRM_MODE_OBJECT_CONNECTOR:
420 		ret = drm_mode_connector_set_obj_prop(arg_obj, property,
421 						      arg->value);
422 		break;
423 	case DRM_MODE_OBJECT_CRTC:
424 		ret = drm_mode_crtc_set_obj_prop(arg_obj, property, arg->value);
425 		break;
426 	case DRM_MODE_OBJECT_PLANE:
427 		ret = drm_mode_plane_set_obj_prop(obj_to_plane(arg_obj),
428 						  property, arg->value);
429 		break;
430 	}
431 
432 	drm_property_change_valid_put(property, ref);
433 
434 out_unref:
435 	drm_mode_object_unreference(arg_obj);
436 out:
437 	drm_modeset_unlock_all(dev);
438 	return ret;
439 }
440