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/compat.h>
24#include <linux/export.h>
25#include <linux/ioctl.h>
26#include <linux/media.h>
27#include <linux/types.h>
28
29#include <media/media-device.h>
30#include <media/media-devnode.h>
31#include <media/media-entity.h>
32
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
63	if (copy_to_user(__info, &info, sizeof(*__info)))
64		return -EFAULT;
65	return 0;
66}
67
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	memset(&u_ent, 0, sizeof(u_ent));
97	if (copy_from_user(&u_ent.id, &uent->id, sizeof(u_ent.id)))
98		return -EFAULT;
99
100	ent = find_entity(mdev, u_ent.id);
101
102	if (ent == NULL)
103		return -EINVAL;
104
105	u_ent.id = ent->id;
106	if (ent->name)
107		strlcpy(u_ent.name, ent->name, sizeof(u_ent.name));
108	u_ent.type = ent->type;
109	u_ent.revision = ent->revision;
110	u_ent.flags = ent->flags;
111	u_ent.group_id = ent->group_id;
112	u_ent.pads = ent->num_pads;
113	u_ent.links = ent->num_links - ent->num_backlinks;
114	memcpy(&u_ent.raw, &ent->info, sizeof(ent->info));
115	if (copy_to_user(uent, &u_ent, sizeof(u_ent)))
116		return -EFAULT;
117	return 0;
118}
119
120static void media_device_kpad_to_upad(const struct media_pad *kpad,
121				      struct media_pad_desc *upad)
122{
123	upad->entity = kpad->entity->id;
124	upad->index = kpad->index;
125	upad->flags = kpad->flags;
126}
127
128static long __media_device_enum_links(struct media_device *mdev,
129				      struct media_links_enum *links)
130{
131	struct media_entity *entity;
132
133	entity = find_entity(mdev, links->entity);
134	if (entity == NULL)
135		return -EINVAL;
136
137	if (links->pads) {
138		unsigned int p;
139
140		for (p = 0; p < entity->num_pads; p++) {
141			struct media_pad_desc pad;
142
143			memset(&pad, 0, sizeof(pad));
144			media_device_kpad_to_upad(&entity->pads[p], &pad);
145			if (copy_to_user(&links->pads[p], &pad, sizeof(pad)))
146				return -EFAULT;
147		}
148	}
149
150	if (links->links) {
151		struct media_link_desc __user *ulink;
152		unsigned int l;
153
154		for (l = 0, ulink = links->links; l < entity->num_links; l++) {
155			struct media_link_desc link;
156
157			/* Ignore backlinks. */
158			if (entity->links[l].source->entity != entity)
159				continue;
160
161			memset(&link, 0, sizeof(link));
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	}
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
189	if (copy_to_user(ulinks, &links, sizeof(*ulinks)))
190		return -EFAULT;
191
192	return 0;
193}
194
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
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
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
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
265	default:
266		ret = -ENOIOCTLCMD;
267	}
268
269	return ret;
270}
271
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
330static const struct media_file_operations media_device_fops = {
331	.owner = THIS_MODULE,
332	.open = media_device_open,
333	.ioctl = media_device_ioctl,
334#ifdef CONFIG_COMPAT
335	.compat_ioctl = media_device_compat_ioctl,
336#endif /* CONFIG_COMPAT */
337	.release = media_device_close,
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					 struct module *owner)
374{
375	int ret;
376
377	if (WARN_ON(mdev->dev == NULL || mdev->model[0] == 0))
378		return -EINVAL;
379
380	mdev->entity_id = 1;
381	INIT_LIST_HEAD(&mdev->entities);
382	spin_lock_init(&mdev->lock);
383	mutex_init(&mdev->graph_mutex);
384
385	/* Register the device node. */
386	mdev->devnode.fops = &media_device_fops;
387	mdev->devnode.parent = mdev->dev;
388	mdev->devnode.release = media_device_release;
389	ret = media_devnode_register(&mdev->devnode, owner);
390	if (ret < 0)
391		return ret;
392
393	ret = device_create_file(&mdev->devnode.dev, &dev_attr_model);
394	if (ret < 0) {
395		media_devnode_unregister(&mdev->devnode);
396		return ret;
397	}
398
399	return 0;
400}
401EXPORT_SYMBOL_GPL(__media_device_register);
402
403/**
404 * media_device_unregister - unregister a media device
405 * @mdev:	The media device
406 *
407 */
408void media_device_unregister(struct media_device *mdev)
409{
410	struct media_entity *entity;
411	struct media_entity *next;
412
413	list_for_each_entry_safe(entity, next, &mdev->entities, list)
414		media_device_unregister_entity(entity);
415
416	device_remove_file(&mdev->devnode.dev, &dev_attr_model);
417	media_devnode_unregister(&mdev->devnode);
418}
419EXPORT_SYMBOL_GPL(media_device_unregister);
420
421/**
422 * media_device_register_entity - Register an entity with a media device
423 * @mdev:	The media device
424 * @entity:	The entity
425 */
426int __must_check media_device_register_entity(struct media_device *mdev,
427					      struct media_entity *entity)
428{
429	/* Warn if we apparently re-register an entity */
430	WARN_ON(entity->parent != NULL);
431	entity->parent = mdev;
432
433	spin_lock(&mdev->lock);
434	if (entity->id == 0)
435		entity->id = mdev->entity_id++;
436	else
437		mdev->entity_id = max(entity->id + 1, mdev->entity_id);
438	list_add_tail(&entity->list, &mdev->entities);
439	spin_unlock(&mdev->lock);
440
441	return 0;
442}
443EXPORT_SYMBOL_GPL(media_device_register_entity);
444
445/**
446 * media_device_unregister_entity - Unregister an entity
447 * @entity:	The entity
448 *
449 * If the entity has never been registered this function will return
450 * immediately.
451 */
452void media_device_unregister_entity(struct media_entity *entity)
453{
454	struct media_device *mdev = entity->parent;
455
456	if (mdev == NULL)
457		return;
458
459	spin_lock(&mdev->lock);
460	list_del(&entity->list);
461	spin_unlock(&mdev->lock);
462	entity->parent = NULL;
463}
464EXPORT_SYMBOL_GPL(media_device_unregister_entity);
465