clk: vexpress: NULL dereference on error path
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / media / media-device.c
CommitLineData
176fb0d1
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1/*
2 * Media device
3 *
4 * Copyright (C) 2010 Nokia Corporation
5 *
6 * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
7 * Sakari Ailus <sakari.ailus@iki.fi>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 */
22
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23#include <linux/compat.h>
24#include <linux/export.h>
176fb0d1 25#include <linux/ioctl.h>
140d8816 26#include <linux/media.h>
b0a1f2a8 27#include <linux/types.h>
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28
29#include <media/media-device.h>
30#include <media/media-devnode.h>
53e269c1 31#include <media/media-entity.h>
176fb0d1 32
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33/* -----------------------------------------------------------------------------
34 * Userspace API
35 */
36
37static int media_device_open(struct file *filp)
38{
39 return 0;
40}
41
42static int media_device_close(struct file *filp)
43{
44 return 0;
45}
46
47static int media_device_get_info(struct media_device *dev,
48 struct media_device_info __user *__info)
49{
50 struct media_device_info info;
51
52 memset(&info, 0, sizeof(info));
53
54 strlcpy(info.driver, dev->dev->driver->name, sizeof(info.driver));
55 strlcpy(info.model, dev->model, sizeof(info.model));
56 strlcpy(info.serial, dev->serial, sizeof(info.serial));
57 strlcpy(info.bus_info, dev->bus_info, sizeof(info.bus_info));
58
59 info.media_version = MEDIA_API_VERSION;
60 info.hw_revision = dev->hw_revision;
61 info.driver_version = dev->driver_version;
62
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63 if (copy_to_user(__info, &info, sizeof(*__info)))
64 return -EFAULT;
65 return 0;
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66}
67
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68static struct media_entity *find_entity(struct media_device *mdev, u32 id)
69{
70 struct media_entity *entity;
71 int next = id & MEDIA_ENT_ID_FLAG_NEXT;
72
73 id &= ~MEDIA_ENT_ID_FLAG_NEXT;
74
75 spin_lock(&mdev->lock);
76
77 media_device_for_each_entity(entity, mdev) {
78 if ((entity->id == id && !next) ||
79 (entity->id > id && next)) {
80 spin_unlock(&mdev->lock);
81 return entity;
82 }
83 }
84
85 spin_unlock(&mdev->lock);
86
87 return NULL;
88}
89
90static long media_device_enum_entities(struct media_device *mdev,
91 struct media_entity_desc __user *uent)
92{
93 struct media_entity *ent;
94 struct media_entity_desc u_ent;
95
96 if (copy_from_user(&u_ent.id, &uent->id, sizeof(u_ent.id)))
97 return -EFAULT;
98
99 ent = find_entity(mdev, u_ent.id);
100
101 if (ent == NULL)
102 return -EINVAL;
103
104 u_ent.id = ent->id;
c06ca8f9
DC
105 if (ent->name) {
106 strncpy(u_ent.name, ent->name, sizeof(u_ent.name));
107 u_ent.name[sizeof(u_ent.name) - 1] = '\0';
108 } else {
109 memset(u_ent.name, 0, sizeof(u_ent.name));
110 }
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111 u_ent.type = ent->type;
112 u_ent.revision = ent->revision;
113 u_ent.flags = ent->flags;
114 u_ent.group_id = ent->group_id;
115 u_ent.pads = ent->num_pads;
116 u_ent.links = ent->num_links - ent->num_backlinks;
fa5034c6 117 memcpy(&u_ent.raw, &ent->info, sizeof(ent->info));
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118 if (copy_to_user(uent, &u_ent, sizeof(u_ent)))
119 return -EFAULT;
120 return 0;
121}
122
123static void media_device_kpad_to_upad(const struct media_pad *kpad,
124 struct media_pad_desc *upad)
125{
126 upad->entity = kpad->entity->id;
127 upad->index = kpad->index;
128 upad->flags = kpad->flags;
129}
130
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131static long __media_device_enum_links(struct media_device *mdev,
132 struct media_links_enum *links)
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133{
134 struct media_entity *entity;
1651333b 135
b0a1f2a8 136 entity = find_entity(mdev, links->entity);
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137 if (entity == NULL)
138 return -EINVAL;
139
b0a1f2a8 140 if (links->pads) {
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141 unsigned int p;
142
143 for (p = 0; p < entity->num_pads; p++) {
144 struct media_pad_desc pad;
145 media_device_kpad_to_upad(&entity->pads[p], &pad);
b0a1f2a8 146 if (copy_to_user(&links->pads[p], &pad, sizeof(pad)))
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147 return -EFAULT;
148 }
149 }
150
b0a1f2a8 151 if (links->links) {
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152 struct media_link_desc __user *ulink;
153 unsigned int l;
154
b0a1f2a8 155 for (l = 0, ulink = links->links; l < entity->num_links; l++) {
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156 struct media_link_desc link;
157
158 /* Ignore backlinks. */
159 if (entity->links[l].source->entity != entity)
160 continue;
161
162 media_device_kpad_to_upad(entity->links[l].source,
163 &link.source);
164 media_device_kpad_to_upad(entity->links[l].sink,
165 &link.sink);
166 link.flags = entity->links[l].flags;
167 if (copy_to_user(ulink, &link, sizeof(*ulink)))
168 return -EFAULT;
169 ulink++;
170 }
171 }
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SA
172
173 return 0;
174}
175
176static long media_device_enum_links(struct media_device *mdev,
177 struct media_links_enum __user *ulinks)
178{
179 struct media_links_enum links;
180 int rval;
181
182 if (copy_from_user(&links, ulinks, sizeof(links)))
183 return -EFAULT;
184
185 rval = __media_device_enum_links(mdev, &links);
186 if (rval < 0)
187 return rval;
188
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LP
189 if (copy_to_user(ulinks, &links, sizeof(*ulinks)))
190 return -EFAULT;
b0a1f2a8 191
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192 return 0;
193}
194
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195static long media_device_setup_link(struct media_device *mdev,
196 struct media_link_desc __user *_ulink)
197{
198 struct media_link *link = NULL;
199 struct media_link_desc ulink;
200 struct media_entity *source;
201 struct media_entity *sink;
202 int ret;
203
204 if (copy_from_user(&ulink, _ulink, sizeof(ulink)))
205 return -EFAULT;
206
207 /* Find the source and sink entities and link.
208 */
209 source = find_entity(mdev, ulink.source.entity);
210 sink = find_entity(mdev, ulink.sink.entity);
211
212 if (source == NULL || sink == NULL)
213 return -EINVAL;
214
215 if (ulink.source.index >= source->num_pads ||
216 ulink.sink.index >= sink->num_pads)
217 return -EINVAL;
218
219 link = media_entity_find_link(&source->pads[ulink.source.index],
220 &sink->pads[ulink.sink.index]);
221 if (link == NULL)
222 return -EINVAL;
223
224 /* Setup the link on both entities. */
225 ret = __media_entity_setup_link(link, ulink.flags);
226
227 if (copy_to_user(_ulink, &ulink, sizeof(ulink)))
228 return -EFAULT;
229
230 return ret;
231}
232
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LP
233static long media_device_ioctl(struct file *filp, unsigned int cmd,
234 unsigned long arg)
235{
236 struct media_devnode *devnode = media_devnode_data(filp);
237 struct media_device *dev = to_media_device(devnode);
238 long ret;
239
240 switch (cmd) {
241 case MEDIA_IOC_DEVICE_INFO:
242 ret = media_device_get_info(dev,
243 (struct media_device_info __user *)arg);
244 break;
245
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LP
246 case MEDIA_IOC_ENUM_ENTITIES:
247 ret = media_device_enum_entities(dev,
248 (struct media_entity_desc __user *)arg);
249 break;
250
251 case MEDIA_IOC_ENUM_LINKS:
252 mutex_lock(&dev->graph_mutex);
253 ret = media_device_enum_links(dev,
254 (struct media_links_enum __user *)arg);
255 mutex_unlock(&dev->graph_mutex);
256 break;
257
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LP
258 case MEDIA_IOC_SETUP_LINK:
259 mutex_lock(&dev->graph_mutex);
260 ret = media_device_setup_link(dev,
261 (struct media_link_desc __user *)arg);
262 mutex_unlock(&dev->graph_mutex);
263 break;
264
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LP
265 default:
266 ret = -ENOIOCTLCMD;
267 }
268
269 return ret;
270}
271
b0a1f2a8
SA
272#ifdef CONFIG_COMPAT
273
274struct media_links_enum32 {
275 __u32 entity;
276 compat_uptr_t pads; /* struct media_pad_desc * */
277 compat_uptr_t links; /* struct media_link_desc * */
278 __u32 reserved[4];
279};
280
281static long media_device_enum_links32(struct media_device *mdev,
282 struct media_links_enum32 __user *ulinks)
283{
284 struct media_links_enum links;
285 compat_uptr_t pads_ptr, links_ptr;
286
287 memset(&links, 0, sizeof(links));
288
289 if (get_user(links.entity, &ulinks->entity)
290 || get_user(pads_ptr, &ulinks->pads)
291 || get_user(links_ptr, &ulinks->links))
292 return -EFAULT;
293
294 links.pads = compat_ptr(pads_ptr);
295 links.links = compat_ptr(links_ptr);
296
297 return __media_device_enum_links(mdev, &links);
298}
299
300#define MEDIA_IOC_ENUM_LINKS32 _IOWR('|', 0x02, struct media_links_enum32)
301
302static long media_device_compat_ioctl(struct file *filp, unsigned int cmd,
303 unsigned long arg)
304{
305 struct media_devnode *devnode = media_devnode_data(filp);
306 struct media_device *dev = to_media_device(devnode);
307 long ret;
308
309 switch (cmd) {
310 case MEDIA_IOC_DEVICE_INFO:
311 case MEDIA_IOC_ENUM_ENTITIES:
312 case MEDIA_IOC_SETUP_LINK:
313 return media_device_ioctl(filp, cmd, arg);
314
315 case MEDIA_IOC_ENUM_LINKS32:
316 mutex_lock(&dev->graph_mutex);
317 ret = media_device_enum_links32(dev,
318 (struct media_links_enum32 __user *)arg);
319 mutex_unlock(&dev->graph_mutex);
320 break;
321
322 default:
323 ret = -ENOIOCTLCMD;
324 }
325
326 return ret;
327}
328#endif /* CONFIG_COMPAT */
329
176fb0d1
LP
330static const struct media_file_operations media_device_fops = {
331 .owner = THIS_MODULE,
140d8816
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332 .open = media_device_open,
333 .ioctl = media_device_ioctl,
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SA
334#ifdef CONFIG_COMPAT
335 .compat_ioctl = media_device_compat_ioctl,
336#endif /* CONFIG_COMPAT */
140d8816 337 .release = media_device_close,
176fb0d1
LP
338};
339
340/* -----------------------------------------------------------------------------
341 * sysfs
342 */
343
344static ssize_t show_model(struct device *cd,
345 struct device_attribute *attr, char *buf)
346{
347 struct media_device *mdev = to_media_device(to_media_devnode(cd));
348
349 return sprintf(buf, "%.*s\n", (int)sizeof(mdev->model), mdev->model);
350}
351
352static DEVICE_ATTR(model, S_IRUGO, show_model, NULL);
353
354/* -----------------------------------------------------------------------------
355 * Registration/unregistration
356 */
357
358static void media_device_release(struct media_devnode *mdev)
359{
360}
361
362/**
363 * media_device_register - register a media device
364 * @mdev: The media device
365 *
366 * The caller is responsible for initializing the media device before
367 * registration. The following fields must be set:
368 *
369 * - dev must point to the parent device
370 * - model must be filled with the device model name
371 */
372int __must_check media_device_register(struct media_device *mdev)
373{
374 int ret;
375
376 if (WARN_ON(mdev->dev == NULL || mdev->model[0] == 0))
377 return -EINVAL;
378
53e269c1
LP
379 mdev->entity_id = 1;
380 INIT_LIST_HEAD(&mdev->entities);
381 spin_lock_init(&mdev->lock);
503c3d82 382 mutex_init(&mdev->graph_mutex);
53e269c1 383
176fb0d1
LP
384 /* Register the device node. */
385 mdev->devnode.fops = &media_device_fops;
386 mdev->devnode.parent = mdev->dev;
387 mdev->devnode.release = media_device_release;
388 ret = media_devnode_register(&mdev->devnode);
389 if (ret < 0)
390 return ret;
391
392 ret = device_create_file(&mdev->devnode.dev, &dev_attr_model);
393 if (ret < 0) {
394 media_devnode_unregister(&mdev->devnode);
395 return ret;
396 }
397
398 return 0;
399}
400EXPORT_SYMBOL_GPL(media_device_register);
401
402/**
403 * media_device_unregister - unregister a media device
404 * @mdev: The media device
405 *
406 */
407void media_device_unregister(struct media_device *mdev)
408{
53e269c1
LP
409 struct media_entity *entity;
410 struct media_entity *next;
411
412 list_for_each_entry_safe(entity, next, &mdev->entities, list)
413 media_device_unregister_entity(entity);
414
176fb0d1
LP
415 device_remove_file(&mdev->devnode.dev, &dev_attr_model);
416 media_devnode_unregister(&mdev->devnode);
417}
418EXPORT_SYMBOL_GPL(media_device_unregister);
53e269c1
LP
419
420/**
421 * media_device_register_entity - Register an entity with a media device
422 * @mdev: The media device
423 * @entity: The entity
424 */
425int __must_check media_device_register_entity(struct media_device *mdev,
426 struct media_entity *entity)
427{
428 /* Warn if we apparently re-register an entity */
429 WARN_ON(entity->parent != NULL);
430 entity->parent = mdev;
431
432 spin_lock(&mdev->lock);
433 if (entity->id == 0)
434 entity->id = mdev->entity_id++;
435 else
436 mdev->entity_id = max(entity->id + 1, mdev->entity_id);
437 list_add_tail(&entity->list, &mdev->entities);
438 spin_unlock(&mdev->lock);
439
440 return 0;
441}
442EXPORT_SYMBOL_GPL(media_device_register_entity);
443
444/**
445 * media_device_unregister_entity - Unregister an entity
446 * @entity: The entity
447 *
448 * If the entity has never been registered this function will return
449 * immediately.
450 */
451void media_device_unregister_entity(struct media_entity *entity)
452{
453 struct media_device *mdev = entity->parent;
454
455 if (mdev == NULL)
456 return;
457
458 spin_lock(&mdev->lock);
459 list_del(&entity->list);
460 spin_unlock(&mdev->lock);
461 entity->parent = NULL;
462}
463EXPORT_SYMBOL_GPL(media_device_unregister_entity);