[deliverable/linux.git] / drivers / media / media-device.c

/*
 * Media device
 *
 * Copyright (C) 2010 Nokia Corporation
 *
 * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
 *	     Sakari Ailus <sakari.ailus@iki.fi>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <linux/compat.h>
#include <linux/export.h>
#include <linux/ioctl.h>
#include <linux/media.h>
#include <linux/types.h>

#include <media/media-device.h>
#include <media/media-devnode.h>
#include <media/media-entity.h>

/* -----------------------------------------------------------------------------
 * Userspace API
 */

static int media_device_open(struct file *filp)
{
	return 0;
}

static int media_device_close(struct file *filp)
{
	return 0;
}

static int media_device_get_info(struct media_device *dev,
				 struct media_device_info __user *__info)
{
	struct media_device_info info;

	memset(&info, 0, sizeof(info));

	strlcpy(info.driver, dev->dev->driver->name, sizeof(info.driver));
	strlcpy(info.model, dev->model, sizeof(info.model));
	strlcpy(info.serial, dev->serial, sizeof(info.serial));
	strlcpy(info.bus_info, dev->bus_info, sizeof(info.bus_info));

	info.media_version = MEDIA_API_VERSION;
	info.hw_revision = dev->hw_revision;
	info.driver_version = dev->driver_version;

	if (copy_to_user(__info, &info, sizeof(*__info)))
		return -EFAULT;
	return 0;
}

static struct media_entity *find_entity(struct media_device *mdev, u32 id)
{
	struct media_entity *entity;
	int next = id & MEDIA_ENT_ID_FLAG_NEXT;

	id &= ~MEDIA_ENT_ID_FLAG_NEXT;

	spin_lock(&mdev->lock);

	media_device_for_each_entity(entity, mdev) {
		if ((entity->id == id && !next) ||
		    (entity->id > id && next)) {
			spin_unlock(&mdev->lock);
			return entity;
		}
	}

	spin_unlock(&mdev->lock);

	return NULL;
}

static long media_device_enum_entities(struct media_device *mdev,
				       struct media_entity_desc __user *uent)
{
	struct media_entity *ent;
	struct media_entity_desc u_ent;

	memset(&u_ent, 0, sizeof(u_ent));
	if (copy_from_user(&u_ent.id, &uent->id, sizeof(u_ent.id)))
		return -EFAULT;

	ent = find_entity(mdev, u_ent.id);

	if (ent == NULL)
		return -EINVAL;

	u_ent.id = ent->id;
	if (ent->name)
		strlcpy(u_ent.name, ent->name, sizeof(u_ent.name));
	u_ent.type = ent->type;
	u_ent.revision = ent->revision;
	u_ent.flags = ent->flags;
	u_ent.group_id = ent->group_id;
	u_ent.pads = ent->num_pads;
	u_ent.links = ent->num_links - ent->num_backlinks;
	memcpy(&u_ent.raw, &ent->info, sizeof(ent->info));
	if (copy_to_user(uent, &u_ent, sizeof(u_ent)))
		return -EFAULT;
	return 0;
}

static void media_device_kpad_to_upad(const struct media_pad *kpad,
				      struct media_pad_desc *upad)
{
	upad->entity = kpad->entity->id;
	upad->index = kpad->index;
	upad->flags = kpad->flags;
}

static long __media_device_enum_links(struct media_device *mdev,
				      struct media_links_enum *links)
{
	struct media_entity *entity;

	entity = find_entity(mdev, links->entity);
	if (entity == NULL)
		return -EINVAL;

	if (links->pads) {
		unsigned int p;

		for (p = 0; p < entity->num_pads; p++) {
			struct media_pad_desc pad;

			memset(&pad, 0, sizeof(pad));
			media_device_kpad_to_upad(&entity->pads[p], &pad);
			if (copy_to_user(&links->pads[p], &pad, sizeof(pad)))
				return -EFAULT;
		}
	}

	if (links->links) {
		struct media_link_desc __user *ulink;
		unsigned int l;

		for (l = 0, ulink = links->links; l < entity->num_links; l++) {
			struct media_link_desc link;

			/* Ignore backlinks. */
			if (entity->links[l].source->entity != entity)
				continue;

			memset(&link, 0, sizeof(link));
			media_device_kpad_to_upad(entity->links[l].source,
						  &link.source);
			media_device_kpad_to_upad(entity->links[l].sink,
						  &link.sink);
			link.flags = entity->links[l].flags;
			if (copy_to_user(ulink, &link, sizeof(*ulink)))
				return -EFAULT;
			ulink++;
		}
	}

	return 0;
}

static long media_device_enum_links(struct media_device *mdev,
				    struct media_links_enum __user *ulinks)
{
	struct media_links_enum links;
	int rval;

	if (copy_from_user(&links, ulinks, sizeof(links)))
		return -EFAULT;

	rval = __media_device_enum_links(mdev, &links);
	if (rval < 0)
		return rval;

	if (copy_to_user(ulinks, &links, sizeof(*ulinks)))
		return -EFAULT;

	return 0;
}

static long media_device_setup_link(struct media_device *mdev,
				    struct media_link_desc __user *_ulink)
{
	struct media_link *link = NULL;
	struct media_link_desc ulink;
	struct media_entity *source;
	struct media_entity *sink;
	int ret;

	if (copy_from_user(&ulink, _ulink, sizeof(ulink)))
		return -EFAULT;

	/* Find the source and sink entities and link.
	 */
	source = find_entity(mdev, ulink.source.entity);
	sink = find_entity(mdev, ulink.sink.entity);

	if (source == NULL || sink == NULL)
		return -EINVAL;

	if (ulink.source.index >= source->num_pads ||
	    ulink.sink.index >= sink->num_pads)
		return -EINVAL;

	link = media_entity_find_link(&source->pads[ulink.source.index],
				      &sink->pads[ulink.sink.index]);
	if (link == NULL)
		return -EINVAL;

	/* Setup the link on both entities. */
	ret = __media_entity_setup_link(link, ulink.flags);

	if (copy_to_user(_ulink, &ulink, sizeof(ulink)))
		return -EFAULT;

	return ret;
}

static long media_device_ioctl(struct file *filp, unsigned int cmd,
			       unsigned long arg)
{
	struct media_devnode *devnode = media_devnode_data(filp);
	struct media_device *dev = to_media_device(devnode);
	long ret;

	switch (cmd) {
	case MEDIA_IOC_DEVICE_INFO:
		ret = media_device_get_info(dev,
				(struct media_device_info __user *)arg);
		break;

	case MEDIA_IOC_ENUM_ENTITIES:
		ret = media_device_enum_entities(dev,
				(struct media_entity_desc __user *)arg);
		break;

	case MEDIA_IOC_ENUM_LINKS:
		mutex_lock(&dev->graph_mutex);
		ret = media_device_enum_links(dev,
				(struct media_links_enum __user *)arg);
		mutex_unlock(&dev->graph_mutex);
		break;

	case MEDIA_IOC_SETUP_LINK:
		mutex_lock(&dev->graph_mutex);
		ret = media_device_setup_link(dev,
				(struct media_link_desc __user *)arg);
		mutex_unlock(&dev->graph_mutex);
		break;

	default:
		ret = -ENOIOCTLCMD;
	}

	return ret;
}

#ifdef CONFIG_COMPAT

struct media_links_enum32 {
	__u32 entity;
	compat_uptr_t pads; /* struct media_pad_desc * */
	compat_uptr_t links; /* struct media_link_desc * */
	__u32 reserved[4];
};

static long media_device_enum_links32(struct media_device *mdev,
				      struct media_links_enum32 __user *ulinks)
{
	struct media_links_enum links;
	compat_uptr_t pads_ptr, links_ptr;

	memset(&links, 0, sizeof(links));

	if (get_user(links.entity, &ulinks->entity)
	    || get_user(pads_ptr, &ulinks->pads)
	    || get_user(links_ptr, &ulinks->links))
		return -EFAULT;

	links.pads = compat_ptr(pads_ptr);
	links.links = compat_ptr(links_ptr);

	return __media_device_enum_links(mdev, &links);
}

#define MEDIA_IOC_ENUM_LINKS32		_IOWR('|', 0x02, struct media_links_enum32)

static long media_device_compat_ioctl(struct file *filp, unsigned int cmd,
				      unsigned long arg)
{
	struct media_devnode *devnode = media_devnode_data(filp);
	struct media_device *dev = to_media_device(devnode);
	long ret;

	switch (cmd) {
	case MEDIA_IOC_DEVICE_INFO:
	case MEDIA_IOC_ENUM_ENTITIES:
	case MEDIA_IOC_SETUP_LINK:
		return media_device_ioctl(filp, cmd, arg);

	case MEDIA_IOC_ENUM_LINKS32:
		mutex_lock(&dev->graph_mutex);
		ret = media_device_enum_links32(dev,
				(struct media_links_enum32 __user *)arg);
		mutex_unlock(&dev->graph_mutex);
		break;

	default:
		ret = -ENOIOCTLCMD;
	}

	return ret;
}
#endif /* CONFIG_COMPAT */

static const struct media_file_operations media_device_fops = {
	.owner = THIS_MODULE,
	.open = media_device_open,
	.ioctl = media_device_ioctl,
#ifdef CONFIG_COMPAT
	.compat_ioctl = media_device_compat_ioctl,
#endif /* CONFIG_COMPAT */
	.release = media_device_close,
};

/* -----------------------------------------------------------------------------
 * sysfs
 */

static ssize_t show_model(struct device *cd,
			  struct device_attribute *attr, char *buf)
{
	struct media_device *mdev = to_media_device(to_media_devnode(cd));

	return sprintf(buf, "%.*s\n", (int)sizeof(mdev->model), mdev->model);
}

static DEVICE_ATTR(model, S_IRUGO, show_model, NULL);

/* -----------------------------------------------------------------------------
 * Registration/unregistration
 */

static void media_device_release(struct media_devnode *mdev)
{
}

/**
 * media_device_register - register a media device
 * @mdev:	The media device
 *
 * The caller is responsible for initializing the media device before
 * registration. The following fields must be set:
 *
 * - dev must point to the parent device
 * - model must be filled with the device model name
 */
int __must_check __media_device_register(struct media_device *mdev,
					 struct module *owner)
{
	int ret;

	if (WARN_ON(mdev->dev == NULL || mdev->model[0] == 0))
		return -EINVAL;

	mdev->entity_id = 1;
	INIT_LIST_HEAD(&mdev->entities);
	spin_lock_init(&mdev->lock);
	mutex_init(&mdev->graph_mutex);

	/* Register the device node. */
	mdev->devnode.fops = &media_device_fops;
	mdev->devnode.parent = mdev->dev;
	mdev->devnode.release = media_device_release;
	ret = media_devnode_register(&mdev->devnode, owner);
	if (ret < 0)
		return ret;

	ret = device_create_file(&mdev->devnode.dev, &dev_attr_model);
	if (ret < 0) {
		media_devnode_unregister(&mdev->devnode);
		return ret;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(__media_device_register);

/**
 * media_device_unregister - unregister a media device
 * @mdev:	The media device
 *
 */
void media_device_unregister(struct media_device *mdev)
{
	struct media_entity *entity;
	struct media_entity *next;

	list_for_each_entry_safe(entity, next, &mdev->entities, list)
		media_device_unregister_entity(entity);

	device_remove_file(&mdev->devnode.dev, &dev_attr_model);
	media_devnode_unregister(&mdev->devnode);
}
EXPORT_SYMBOL_GPL(media_device_unregister);

/**
 * media_device_register_entity - Register an entity with a media device
 * @mdev:	The media device
 * @entity:	The entity
 */
int __must_check media_device_register_entity(struct media_device *mdev,
					      struct media_entity *entity)
{
	/* Warn if we apparently re-register an entity */
	WARN_ON(entity->parent != NULL);
	entity->parent = mdev;

	spin_lock(&mdev->lock);
	if (entity->id == 0)
		entity->id = mdev->entity_id++;
	else
		mdev->entity_id = max(entity->id + 1, mdev->entity_id);
	list_add_tail(&entity->list, &mdev->entities);
	spin_unlock(&mdev->lock);

	return 0;
}
EXPORT_SYMBOL_GPL(media_device_register_entity);

/**
 * media_device_unregister_entity - Unregister an entity
 * @entity:	The entity
 *
 * If the entity has never been registered this function will return
 * immediately.
 */
void media_device_unregister_entity(struct media_entity *entity)
{
	struct media_device *mdev = entity->parent;

	if (mdev == NULL)
		return;

	spin_lock(&mdev->lock);
	list_del(&entity->list);
	spin_unlock(&mdev->lock);
	entity->parent = NULL;
}
EXPORT_SYMBOL_GPL(media_device_unregister_entity);
Commit	Line	Data
176fb0d1 LP	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
b0a1f2a8 SA	23	#include <linux/compat.h>
b0a1f2a8 SA	24	#include <linux/export.h>
176fb0d1	25	#include <linux/ioctl.h>
140d8816	26	#include <linux/media.h>
b0a1f2a8	27	#include <linux/types.h>
176fb0d1 LP	28
	29	#include <media/media-device.h>
	30	#include <media/media-devnode.h>
53e269c1	31	#include <media/media-entity.h>
176fb0d1	32
140d8816 LP	33	/* -----------------------------------------------------------------------------
	34	* Userspace API
	35	*/
	36
	37	static int media_device_open(struct file *filp)
	38	{
	39	return 0;
	40	}
	41
	42	static int media_device_close(struct file *filp)
	43	{
	44	return 0;
	45	}
	46
	47	static 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
b17d3945 NT	63	if (copy_to_user(__info, &info, sizeof(*__info)))
	64	return -EFAULT;
	65	return 0;
140d8816 LP	66	}
140d8816 LP	67
1651333b LP	68	static 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
	90	static 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
e6a62346	96	memset(&u_ent, 0, sizeof(u_ent));
1651333b LP	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;
de8eae36 LP	106	if (ent->name)
de8eae36 LP	107	strlcpy(u_ent.name, ent->name, sizeof(u_ent.name));
1651333b LP	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;
fa5034c6	114	memcpy(&u_ent.raw, &ent->info, sizeof(ent->info));
1651333b LP	115	if (copy_to_user(uent, &u_ent, sizeof(u_ent)))
	116	return -EFAULT;
	117	return 0;
	118	}
	119
	120	static 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
b0a1f2a8 SA	128	static long __media_device_enum_links(struct media_device *mdev,
b0a1f2a8 SA	129	struct media_links_enum *links)
1651333b LP	130	{
1651333b LP	131	struct media_entity *entity;
1651333b	132
b0a1f2a8	133	entity = find_entity(mdev, links->entity);
1651333b LP	134	if (entity == NULL)
	135	return -EINVAL;
	136
b0a1f2a8	137	if (links->pads) {
1651333b LP	138	unsigned int p;
	139
	140	for (p = 0; p < entity->num_pads; p++) {
	141	struct media_pad_desc pad;
c88e739b DC	142
c88e739b DC	143	memset(&pad, 0, sizeof(pad));
1651333b	144	media_device_kpad_to_upad(&entity->pads[p], &pad);
b0a1f2a8	145	if (copy_to_user(&links->pads[p], &pad, sizeof(pad)))
1651333b LP	146	return -EFAULT;
	147	}
	148	}
	149
b0a1f2a8	150	if (links->links) {
1651333b LP	151	struct media_link_desc __user *ulink;
	152	unsigned int l;
	153
b0a1f2a8	154	for (l = 0, ulink = links->links; l < entity->num_links; l++) {
1651333b LP	155	struct media_link_desc link;
	156
	157	/* Ignore backlinks. */
	158	if (entity->links[l].source->entity != entity)
	159	continue;
	160
c88e739b	161	memset(&link, 0, sizeof(link));
1651333b LP	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	}
b0a1f2a8 SA	172
	173	return 0;
	174	}
	175
	176	static 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
1651333b LP	189	if (copy_to_user(ulinks, &links, sizeof(*ulinks)))
1651333b LP	190	return -EFAULT;
b0a1f2a8	191
1651333b LP	192	return 0;
	193	}
	194
97548ed4 LP	195	static 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
140d8816 LP	233	static 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
1651333b 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
97548ed4 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
140d8816 LP	265	default:
	266	ret = -ENOIOCTLCMD;
	267	}
	268
	269	return ret;
	270	}
	271
b0a1f2a8 SA	272	#ifdef CONFIG_COMPAT
	273
	274	struct 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
	281	static 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
	302	static 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	330	static const struct media_file_operations media_device_fops = {
176fb0d1 LP	331	.owner = THIS_MODULE,
140d8816 LP	332	.open = media_device_open,
140d8816 LP	333	.ioctl = media_device_ioctl,
b0a1f2a8 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
	344	static 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
	352	static DEVICE_ATTR(model, S_IRUGO, show_model, NULL);
	353
	354	/* -----------------------------------------------------------------------------
	355	* Registration/unregistration
	356	*/
	357
	358	static 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	*/
85de721c SA	372	int __must_check __media_device_register(struct media_device *mdev,
85de721c SA	373	struct module *owner)
176fb0d1 LP	374	{
	375	int ret;
	376
	377	if (WARN_ON(mdev->dev == NULL \|\| mdev->model[0] == 0))
	378	return -EINVAL;
	379
53e269c1 LP	380	mdev->entity_id = 1;
	381	INIT_LIST_HEAD(&mdev->entities);
	382	spin_lock_init(&mdev->lock);
503c3d82	383	mutex_init(&mdev->graph_mutex);
53e269c1	384
176fb0d1 LP	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;
85de721c	389	ret = media_devnode_register(&mdev->devnode, owner);
176fb0d1 LP	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	}
85de721c	401	EXPORT_SYMBOL_GPL(__media_device_register);
176fb0d1 LP	402
	403	/**
	404	* media_device_unregister - unregister a media device
	405	* @mdev: The media device
	406	*
	407	*/
	408	void media_device_unregister(struct media_device *mdev)
	409	{
53e269c1 LP	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
176fb0d1 LP	416	device_remove_file(&mdev->devnode.dev, &dev_attr_model);
	417	media_devnode_unregister(&mdev->devnode);
	418	}
	419	EXPORT_SYMBOL_GPL(media_device_unregister);
53e269c1 LP	420
	421	/**
	422	* media_device_register_entity - Register an entity with a media device
	423	* @mdev: The media device
	424	* @entity: The entity
	425	*/
	426	int __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	}
	443	EXPORT_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	*/
	452	void 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	}
	464	EXPORT_SYMBOL_GPL(media_device_unregister_entity);