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