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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
23#include <linux/types.h>
24#include <linux/ioctl.h>
25#include <linux/media.h>
26#include <linux/export.h>
27
28#include <media/media-device.h>
29#include <media/media-devnode.h>
30#include <media/media-entity.h>
31
32/* -----------------------------------------------------------------------------
33 * Userspace API
34 */
35
36static int media_device_open(struct file *filp)
37{
38 return 0;
39}
40
41static int media_device_close(struct file *filp)
42{
43 return 0;
44}
45
46static int media_device_get_info(struct media_device *dev,
47 struct media_device_info __user *__info)
48{
49 struct media_device_info info;
50
51 memset(&info, 0, sizeof(info));
52
53 strlcpy(info.driver, dev->dev->driver->name, sizeof(info.driver));
54 strlcpy(info.model, dev->model, sizeof(info.model));
55 strlcpy(info.serial, dev->serial, sizeof(info.serial));
56 strlcpy(info.bus_info, dev->bus_info, sizeof(info.bus_info));
57
58 info.media_version = MEDIA_API_VERSION;
59 info.hw_revision = dev->hw_revision;
60 info.driver_version = dev->driver_version;
61
62 return copy_to_user(__info, &info, sizeof(*__info));
63}
64
65static struct media_entity *find_entity(struct media_device *mdev, u32 id)
66{
67 struct media_entity *entity;
68 int next = id & MEDIA_ENT_ID_FLAG_NEXT;
69
70 id &= ~MEDIA_ENT_ID_FLAG_NEXT;
71
72 spin_lock(&mdev->lock);
73
74 media_device_for_each_entity(entity, mdev) {
75 if ((entity->id == id && !next) ||
76 (entity->id > id && next)) {
77 spin_unlock(&mdev->lock);
78 return entity;
79 }
80 }
81
82 spin_unlock(&mdev->lock);
83
84 return NULL;
85}
86
87static long media_device_enum_entities(struct media_device *mdev,
88 struct media_entity_desc __user *uent)
89{
90 struct media_entity *ent;
91 struct media_entity_desc u_ent;
92
93 if (copy_from_user(&u_ent.id, &uent->id, sizeof(u_ent.id)))
94 return -EFAULT;
95
96 ent = find_entity(mdev, u_ent.id);
97
98 if (ent == NULL)
99 return -EINVAL;
100
101 u_ent.id = ent->id;
102 u_ent.name[0] = '\0';
103 if (ent->name)
104 strlcpy(u_ent.name, ent->name, sizeof(u_ent.name));
105 u_ent.type = ent->type;
106 u_ent.revision = ent->revision;
107 u_ent.flags = ent->flags;
108 u_ent.group_id = ent->group_id;
109 u_ent.pads = ent->num_pads;
110 u_ent.links = ent->num_links - ent->num_backlinks;
111 memcpy(&u_ent.raw, &ent->info, sizeof(ent->info));
112 if (copy_to_user(uent, &u_ent, sizeof(u_ent)))
113 return -EFAULT;
114 return 0;
115}
116
117static void media_device_kpad_to_upad(const struct media_pad *kpad,
118 struct media_pad_desc *upad)
119{
120 upad->entity = kpad->entity->id;
121 upad->index = kpad->index;
122 upad->flags = kpad->flags;
123}
124
125static long media_device_enum_links(struct media_device *mdev,
126 struct media_links_enum __user *ulinks)
127{
128 struct media_entity *entity;
129 struct media_links_enum links;
130
131 if (copy_from_user(&links, ulinks, sizeof(links)))
132 return -EFAULT;
133
134 entity = find_entity(mdev, links.entity);
135 if (entity == NULL)
136 return -EINVAL;
137
138 if (links.pads) {
139 unsigned int p;
140
141 for (p = 0; p < entity->num_pads; p++) {
142 struct media_pad_desc pad;
143 media_device_kpad_to_upad(&entity->pads[p], &pad);
144 if (copy_to_user(&links.pads[p], &pad, sizeof(pad)))
145 return -EFAULT;
146 }
147 }
148
149 if (links.links) {
150 struct media_link_desc __user *ulink;
151 unsigned int l;
152
153 for (l = 0, ulink = links.links; l < entity->num_links; l++) {
154 struct media_link_desc link;
155
156 /* Ignore backlinks. */
157 if (entity->links[l].source->entity != entity)
158 continue;
159
160 media_device_kpad_to_upad(entity->links[l].source,
161 &link.source);
162 media_device_kpad_to_upad(entity->links[l].sink,
163 &link.sink);
164 link.flags = entity->links[l].flags;
165 if (copy_to_user(ulink, &link, sizeof(*ulink)))
166 return -EFAULT;
167 ulink++;
168 }
169 }
170 if (copy_to_user(ulinks, &links, sizeof(*ulinks)))
171 return -EFAULT;
172 return 0;
173}
174
175static long media_device_setup_link(struct media_device *mdev,
176 struct media_link_desc __user *_ulink)
177{
178 struct media_link *link = NULL;
179 struct media_link_desc ulink;
180 struct media_entity *source;
181 struct media_entity *sink;
182 int ret;
183
184 if (copy_from_user(&ulink, _ulink, sizeof(ulink)))
185 return -EFAULT;
186
187 /* Find the source and sink entities and link.
188 */
189 source = find_entity(mdev, ulink.source.entity);
190 sink = find_entity(mdev, ulink.sink.entity);
191
192 if (source == NULL || sink == NULL)
193 return -EINVAL;
194
195 if (ulink.source.index >= source->num_pads ||
196 ulink.sink.index >= sink->num_pads)
197 return -EINVAL;
198
199 link = media_entity_find_link(&source->pads[ulink.source.index],
200 &sink->pads[ulink.sink.index]);
201 if (link == NULL)
202 return -EINVAL;
203
204 /* Setup the link on both entities. */
205 ret = __media_entity_setup_link(link, ulink.flags);
206
207 if (copy_to_user(_ulink, &ulink, sizeof(ulink)))
208 return -EFAULT;
209
210 return ret;
211}
212
213static long media_device_ioctl(struct file *filp, unsigned int cmd,
214 unsigned long arg)
215{
216 struct media_devnode *devnode = media_devnode_data(filp);
217 struct media_device *dev = to_media_device(devnode);
218 long ret;
219
220 switch (cmd) {
221 case MEDIA_IOC_DEVICE_INFO:
222 ret = media_device_get_info(dev,
223 (struct media_device_info __user *)arg);
224 break;
225
226 case MEDIA_IOC_ENUM_ENTITIES:
227 ret = media_device_enum_entities(dev,
228 (struct media_entity_desc __user *)arg);
229 break;
230
231 case MEDIA_IOC_ENUM_LINKS:
232 mutex_lock(&dev->graph_mutex);
233 ret = media_device_enum_links(dev,
234 (struct media_links_enum __user *)arg);
235 mutex_unlock(&dev->graph_mutex);
236 break;
237
238 case MEDIA_IOC_SETUP_LINK:
239 mutex_lock(&dev->graph_mutex);
240 ret = media_device_setup_link(dev,
241 (struct media_link_desc __user *)arg);
242 mutex_unlock(&dev->graph_mutex);
243 break;
244
245 default:
246 ret = -ENOIOCTLCMD;
247 }
248
249 return ret;
250}
251
252static const struct media_file_operations media_device_fops = {
253 .owner = THIS_MODULE,
254 .open = media_device_open,
255 .ioctl = media_device_ioctl,
256 .release = media_device_close,
257};
258
259/* -----------------------------------------------------------------------------
260 * sysfs
261 */
262
263static ssize_t show_model(struct device *cd,
264 struct device_attribute *attr, char *buf)
265{
266 struct media_device *mdev = to_media_device(to_media_devnode(cd));
267
268 return sprintf(buf, "%.*s\n", (int)sizeof(mdev->model), mdev->model);
269}
270
271static DEVICE_ATTR(model, S_IRUGO, show_model, NULL);
272
273/* -----------------------------------------------------------------------------
274 * Registration/unregistration
275 */
276
277static void media_device_release(struct media_devnode *mdev)
278{
279}
280
281/**
282 * media_device_register - register a media device
283 * @mdev: The media device
284 *
285 * The caller is responsible for initializing the media device before
286 * registration. The following fields must be set:
287 *
288 * - dev must point to the parent device
289 * - model must be filled with the device model name
290 */
291int __must_check media_device_register(struct media_device *mdev)
292{
293 int ret;
294
295 if (WARN_ON(mdev->dev == NULL || mdev->model[0] == 0))
296 return -EINVAL;
297
298 mdev->entity_id = 1;
299 INIT_LIST_HEAD(&mdev->entities);
300 spin_lock_init(&mdev->lock);
301 mutex_init(&mdev->graph_mutex);
302
303 /* Register the device node. */
304 mdev->devnode.fops = &media_device_fops;
305 mdev->devnode.parent = mdev->dev;
306 mdev->devnode.release = media_device_release;
307 ret = media_devnode_register(&mdev->devnode);
308 if (ret < 0)
309 return ret;
310
311 ret = device_create_file(&mdev->devnode.dev, &dev_attr_model);
312 if (ret < 0) {
313 media_devnode_unregister(&mdev->devnode);
314 return ret;
315 }
316
317 return 0;
318}
319EXPORT_SYMBOL_GPL(media_device_register);
320
321/**
322 * media_device_unregister - unregister a media device
323 * @mdev: The media device
324 *
325 */
326void media_device_unregister(struct media_device *mdev)
327{
328 struct media_entity *entity;
329 struct media_entity *next;
330
331 list_for_each_entry_safe(entity, next, &mdev->entities, list)
332 media_device_unregister_entity(entity);
333
334 device_remove_file(&mdev->devnode.dev, &dev_attr_model);
335 media_devnode_unregister(&mdev->devnode);
336}
337EXPORT_SYMBOL_GPL(media_device_unregister);
338
339/**
340 * media_device_register_entity - Register an entity with a media device
341 * @mdev: The media device
342 * @entity: The entity
343 */
344int __must_check media_device_register_entity(struct media_device *mdev,
345 struct media_entity *entity)
346{
347 /* Warn if we apparently re-register an entity */
348 WARN_ON(entity->parent != NULL);
349 entity->parent = mdev;
350
351 spin_lock(&mdev->lock);
352 if (entity->id == 0)
353 entity->id = mdev->entity_id++;
354 else
355 mdev->entity_id = max(entity->id + 1, mdev->entity_id);
356 list_add_tail(&entity->list, &mdev->entities);
357 spin_unlock(&mdev->lock);
358
359 return 0;
360}
361EXPORT_SYMBOL_GPL(media_device_register_entity);
362
363/**
364 * media_device_unregister_entity - Unregister an entity
365 * @entity: The entity
366 *
367 * If the entity has never been registered this function will return
368 * immediately.
369 */
370void media_device_unregister_entity(struct media_entity *entity)
371{
372 struct media_device *mdev = entity->parent;
373
374 if (mdev == NULL)
375 return;
376
377 spin_lock(&mdev->lock);
378 list_del(&entity->list);
379 spin_unlock(&mdev->lock);
380 entity->parent = NULL;
381}
382EXPORT_SYMBOL_GPL(media_device_unregister_entity);