[deliverable/linux.git] / drivers / media / video / v4l2-device.c

/*
    V4L2 device support.

    Copyright (C) 2008  Hans Verkuil <hverkuil@xs4all.nl>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    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/types.h>
#include <linux/ioctl.h>
#include <linux/i2c.h>
#if defined(CONFIG_SPI)
#include <linux/spi/spi.h>
#endif
#include <linux/videodev2.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ctrls.h>

int v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev)
{
	if (v4l2_dev == NULL)
		return -EINVAL;

	INIT_LIST_HEAD(&v4l2_dev->subdevs);
	spin_lock_init(&v4l2_dev->lock);
	mutex_init(&v4l2_dev->ioctl_lock);
	v4l2_prio_init(&v4l2_dev->prio);
	v4l2_dev->dev = dev;
	if (dev == NULL) {
		/* If dev == NULL, then name must be filled in by the caller */
		WARN_ON(!v4l2_dev->name[0]);
		return 0;
	}

	/* Set name to driver name + device name if it is empty. */
	if (!v4l2_dev->name[0])
		snprintf(v4l2_dev->name, sizeof(v4l2_dev->name), "%s %s",
			dev->driver->name, dev_name(dev));
	if (!dev_get_drvdata(dev))
		dev_set_drvdata(dev, v4l2_dev);
	return 0;
}
EXPORT_SYMBOL_GPL(v4l2_device_register);

int v4l2_device_set_name(struct v4l2_device *v4l2_dev, const char *basename,
						atomic_t *instance)
{
	int num = atomic_inc_return(instance) - 1;
	int len = strlen(basename);

	if (basename[len - 1] >= '0' && basename[len - 1] <= '9')
		snprintf(v4l2_dev->name, sizeof(v4l2_dev->name),
				"%s-%d", basename, num);
	else
		snprintf(v4l2_dev->name, sizeof(v4l2_dev->name),
				"%s%d", basename, num);
	return num;
}
EXPORT_SYMBOL_GPL(v4l2_device_set_name);

void v4l2_device_disconnect(struct v4l2_device *v4l2_dev)
{
	if (v4l2_dev->dev == NULL)
		return;

	if (dev_get_drvdata(v4l2_dev->dev) == v4l2_dev)
		dev_set_drvdata(v4l2_dev->dev, NULL);
	v4l2_dev->dev = NULL;
}
EXPORT_SYMBOL_GPL(v4l2_device_disconnect);

void v4l2_device_unregister(struct v4l2_device *v4l2_dev)
{
	struct v4l2_subdev *sd, *next;

	if (v4l2_dev == NULL)
		return;
	v4l2_device_disconnect(v4l2_dev);

	/* Unregister subdevs */
	list_for_each_entry_safe(sd, next, &v4l2_dev->subdevs, list) {
		v4l2_device_unregister_subdev(sd);
#if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
		if (sd->flags & V4L2_SUBDEV_FL_IS_I2C) {
			struct i2c_client *client = v4l2_get_subdevdata(sd);

			/* We need to unregister the i2c client explicitly.
			   We cannot rely on i2c_del_adapter to always
			   unregister clients for us, since if the i2c bus
			   is a platform bus, then it is never deleted. */
			if (client)
				i2c_unregister_device(client);
			continue;
		}
#endif
#if defined(CONFIG_SPI)
		if (sd->flags & V4L2_SUBDEV_FL_IS_SPI) {
			struct spi_device *spi = v4l2_get_subdevdata(sd);

			if (spi)
				spi_unregister_device(spi);
			continue;
		}
#endif
	}
}
EXPORT_SYMBOL_GPL(v4l2_device_unregister);

int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
				struct v4l2_subdev *sd)
{
#if defined(CONFIG_MEDIA_CONTROLLER)
	struct media_entity *entity = &sd->entity;
#endif
	int err;

	/* Check for valid input */
	if (v4l2_dev == NULL || sd == NULL || !sd->name[0])
		return -EINVAL;

	/* Warn if we apparently re-register a subdev */
	WARN_ON(sd->v4l2_dev != NULL);

	if (!try_module_get(sd->owner))
		return -ENODEV;

	sd->v4l2_dev = v4l2_dev;
	if (sd->internal_ops && sd->internal_ops->registered) {
		err = sd->internal_ops->registered(sd);
		if (err)
			return err;
	}

	/* This just returns 0 if either of the two args is NULL */
	err = v4l2_ctrl_add_handler(v4l2_dev->ctrl_handler, sd->ctrl_handler);
	if (err) {
		if (sd->internal_ops && sd->internal_ops->unregistered)
			sd->internal_ops->unregistered(sd);
		return err;
	}

#if defined(CONFIG_MEDIA_CONTROLLER)
	/* Register the entity. */
	if (v4l2_dev->mdev) {
		err = media_device_register_entity(v4l2_dev->mdev, entity);
		if (err < 0) {
			if (sd->internal_ops && sd->internal_ops->unregistered)
				sd->internal_ops->unregistered(sd);
			module_put(sd->owner);
			return err;
		}
	}
#endif

	spin_lock(&v4l2_dev->lock);
	list_add_tail(&sd->list, &v4l2_dev->subdevs);
	spin_unlock(&v4l2_dev->lock);

	return 0;
}
EXPORT_SYMBOL_GPL(v4l2_device_register_subdev);

int v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev)
{
	struct video_device *vdev;
	struct v4l2_subdev *sd;
	int err;

	/* Register a device node for every subdev marked with the
	 * V4L2_SUBDEV_FL_HAS_DEVNODE flag.
	 */
	list_for_each_entry(sd, &v4l2_dev->subdevs, list) {
		if (!(sd->flags & V4L2_SUBDEV_FL_HAS_DEVNODE))
			continue;

		vdev = &sd->devnode;
		strlcpy(vdev->name, sd->name, sizeof(vdev->name));
		vdev->v4l2_dev = v4l2_dev;
		vdev->fops = &v4l2_subdev_fops;
		vdev->release = video_device_release_empty;
		err = __video_register_device(vdev, VFL_TYPE_SUBDEV, -1, 1,
					      sd->owner);
		if (err < 0)
			return err;
#if defined(CONFIG_MEDIA_CONTROLLER)
		sd->entity.v4l.major = VIDEO_MAJOR;
		sd->entity.v4l.minor = vdev->minor;
#endif
	}
	return 0;
}
EXPORT_SYMBOL_GPL(v4l2_device_register_subdev_nodes);

void v4l2_device_unregister_subdev(struct v4l2_subdev *sd)
{
	struct v4l2_device *v4l2_dev;

	/* return if it isn't registered */
	if (sd == NULL || sd->v4l2_dev == NULL)
		return;

	v4l2_dev = sd->v4l2_dev;

	spin_lock(&v4l2_dev->lock);
	list_del(&sd->list);
	spin_unlock(&v4l2_dev->lock);

	if (sd->internal_ops && sd->internal_ops->unregistered)
		sd->internal_ops->unregistered(sd);
	sd->v4l2_dev = NULL;

#if defined(CONFIG_MEDIA_CONTROLLER)
	if (v4l2_dev->mdev)
		media_device_unregister_entity(&sd->entity);
#endif
	video_unregister_device(&sd->devnode);
	module_put(sd->owner);
}
EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev);
Commit	Line	Data
2a1fcdf0 HV	1	/*
	2	V4L2 device support.
	3
	4	Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>
	5
	6	This program is free software; you can redistribute it and/or modify
	7	it under the terms of the GNU General Public License as published by
	8	the Free Software Foundation; either version 2 of the License, or
	9	(at your option) any later version.
	10
	11	This program is distributed in the hope that it will be useful,
	12	but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	GNU General Public License for more details.
	15
	16	You should have received a copy of the GNU General Public License
	17	along with this program; if not, write to the Free Software
	18	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	19	*/
	20
	21	#include <linux/types.h>
	22	#include <linux/ioctl.h>
	23	#include <linux/i2c.h>
85e09219 DB	24	#if defined(CONFIG_SPI)
	25	#include <linux/spi/spi.h>
	26	#endif
2a1fcdf0 HV	27	#include <linux/videodev2.h>
2a1fcdf0 HV	28	#include <media/v4l2-device.h>
11bbc1ca	29	#include <media/v4l2-ctrls.h>
2a1fcdf0 HV	30
	31	int v4l2_device_register(struct device dev, struct v4l2_device v4l2_dev)
	32	{
3a63e449	33	if (v4l2_dev == NULL)
2a1fcdf0	34	return -EINVAL;
3a63e449	35
2a1fcdf0 HV	36	INIT_LIST_HEAD(&v4l2_dev->subdevs);
2a1fcdf0 HV	37	spin_lock_init(&v4l2_dev->lock);
879aa24d	38	mutex_init(&v4l2_dev->ioctl_lock);
0f62fd6a	39	v4l2_prio_init(&v4l2_dev->prio);
2a1fcdf0	40	v4l2_dev->dev = dev;
3a63e449 HV	41	if (dev == NULL) {
	42	/* If dev == NULL, then name must be filled in by the caller */
	43	WARN_ON(!v4l2_dev->name[0]);
	44	return 0;
	45	}
	46
	47	/* Set name to driver name + device name if it is empty. */
	48	if (!v4l2_dev->name[0])
	49	snprintf(v4l2_dev->name, sizeof(v4l2_dev->name), "%s %s",
c3ef01ce	50	dev->driver->name, dev_name(dev));
95db3a60 LP	51	if (!dev_get_drvdata(dev))
95db3a60 LP	52	dev_set_drvdata(dev, v4l2_dev);
2a1fcdf0 HV	53	return 0;
	54	}
	55	EXPORT_SYMBOL_GPL(v4l2_device_register);
	56
102e7813 HV	57	int v4l2_device_set_name(struct v4l2_device v4l2_dev, const char basename,
	58	atomic_t *instance)
	59	{
	60	int num = atomic_inc_return(instance) - 1;
	61	int len = strlen(basename);
	62
	63	if (basename[len - 1] >= '0' && basename[len - 1] <= '9')
	64	snprintf(v4l2_dev->name, sizeof(v4l2_dev->name),
	65	"%s-%d", basename, num);
	66	else
	67	snprintf(v4l2_dev->name, sizeof(v4l2_dev->name),
	68	"%s%d", basename, num);
	69	return num;
	70	}
	71	EXPORT_SYMBOL_GPL(v4l2_device_set_name);
	72
ae6cfaac HV	73	void v4l2_device_disconnect(struct v4l2_device *v4l2_dev)
ae6cfaac HV	74	{
95db3a60 LP	75	if (v4l2_dev->dev == NULL)
	76	return;
	77
	78	if (dev_get_drvdata(v4l2_dev->dev) == v4l2_dev)
ae6cfaac	79	dev_set_drvdata(v4l2_dev->dev, NULL);
95db3a60	80	v4l2_dev->dev = NULL;
ae6cfaac HV	81	}
	82	EXPORT_SYMBOL_GPL(v4l2_device_disconnect);
	83
2a1fcdf0 HV	84	void v4l2_device_unregister(struct v4l2_device *v4l2_dev)
	85	{
	86	struct v4l2_subdev sd, next;
	87
3a63e449	88	if (v4l2_dev == NULL)
2a1fcdf0	89	return;
ae6cfaac HV	90	v4l2_device_disconnect(v4l2_dev);
ae6cfaac HV	91
3a63e449	92	/* Unregister subdevs */
b5b2b7ed	93	list_for_each_entry_safe(sd, next, &v4l2_dev->subdevs, list) {
2a1fcdf0	94	v4l2_device_unregister_subdev(sd);
ef5b5168	95	#if defined(CONFIG_I2C) \|\| (defined(CONFIG_I2C_MODULE) && defined(MODULE))
b5b2b7ed HV	96	if (sd->flags & V4L2_SUBDEV_FL_IS_I2C) {
	97	struct i2c_client *client = v4l2_get_subdevdata(sd);
	98
	99	/* We need to unregister the i2c client explicitly.
	100	We cannot rely on i2c_del_adapter to always
	101	unregister clients for us, since if the i2c bus
	102	is a platform bus, then it is never deleted. */
	103	if (client)
	104	i2c_unregister_device(client);
672dcd54	105	continue;
b5b2b7ed	106	}
85e09219 DB	107	#endif
	108	#if defined(CONFIG_SPI)
	109	if (sd->flags & V4L2_SUBDEV_FL_IS_SPI) {
	110	struct spi_device *spi = v4l2_get_subdevdata(sd);
	111
	112	if (spi)
	113	spi_unregister_device(spi);
672dcd54	114	continue;
85e09219	115	}
b7fd6067	116	#endif
b5b2b7ed	117	}
2a1fcdf0 HV	118	}
	119	EXPORT_SYMBOL_GPL(v4l2_device_unregister);
	120
3a63e449	121	int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
61f5db54	122	struct v4l2_subdev *sd)
2a1fcdf0	123	{
61f5db54 LP	124	#if defined(CONFIG_MEDIA_CONTROLLER)
	125	struct media_entity *entity = &sd->entity;
	126	#endif
11bbc1ca HV	127	int err;
11bbc1ca HV	128
2a1fcdf0	129	/* Check for valid input */
3a63e449	130	if (v4l2_dev == NULL \|\| sd == NULL \|\| !sd->name[0])
2a1fcdf0	131	return -EINVAL;
2096a5dc	132
2a1fcdf0	133	/* Warn if we apparently re-register a subdev */
b0167600	134	WARN_ON(sd->v4l2_dev != NULL);
2096a5dc	135
2a1fcdf0 HV	136	if (!try_module_get(sd->owner))
2a1fcdf0 HV	137	return -ENODEV;
2096a5dc	138
45f6f84a HV	139	sd->v4l2_dev = v4l2_dev;
	140	if (sd->internal_ops && sd->internal_ops->registered) {
	141	err = sd->internal_ops->registered(sd);
	142	if (err)
	143	return err;
	144	}
2096a5dc	145
11bbc1ca HV	146	/* This just returns 0 if either of the two args is NULL */
11bbc1ca HV	147	err = v4l2_ctrl_add_handler(v4l2_dev->ctrl_handler, sd->ctrl_handler);
45f6f84a HV	148	if (err) {
	149	if (sd->internal_ops && sd->internal_ops->unregistered)
	150	sd->internal_ops->unregistered(sd);
11bbc1ca	151	return err;
45f6f84a	152	}
2096a5dc	153
61f5db54 LP	154	#if defined(CONFIG_MEDIA_CONTROLLER)
	155	/* Register the entity. */
	156	if (v4l2_dev->mdev) {
	157	err = media_device_register_entity(v4l2_dev->mdev, entity);
	158	if (err < 0) {
	159	if (sd->internal_ops && sd->internal_ops->unregistered)
	160	sd->internal_ops->unregistered(sd);
	161	module_put(sd->owner);
	162	return err;
	163	}
	164	}
	165	#endif
	166
3a63e449 HV	167	spin_lock(&v4l2_dev->lock);
	168	list_add_tail(&sd->list, &v4l2_dev->subdevs);
	169	spin_unlock(&v4l2_dev->lock);
2096a5dc	170
2a1fcdf0 HV	171	return 0;
	172	}
	173	EXPORT_SYMBOL_GPL(v4l2_device_register_subdev);
	174
2096a5dc LP	175	int v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev)
	176	{
	177	struct video_device *vdev;
	178	struct v4l2_subdev *sd;
	179	int err;
	180
	181	/* Register a device node for every subdev marked with the
	182	* V4L2_SUBDEV_FL_HAS_DEVNODE flag.
	183	*/
	184	list_for_each_entry(sd, &v4l2_dev->subdevs, list) {
	185	if (!(sd->flags & V4L2_SUBDEV_FL_HAS_DEVNODE))
	186	continue;
	187
	188	vdev = &sd->devnode;
	189	strlcpy(vdev->name, sd->name, sizeof(vdev->name));
	190	vdev->v4l2_dev = v4l2_dev;
	191	vdev->fops = &v4l2_subdev_fops;
	192	vdev->release = video_device_release_empty;
	193	err = __video_register_device(vdev, VFL_TYPE_SUBDEV, -1, 1,
	194	sd->owner);
	195	if (err < 0)
	196	return err;
61f5db54 LP	197	#if defined(CONFIG_MEDIA_CONTROLLER)
	198	sd->entity.v4l.major = VIDEO_MAJOR;
	199	sd->entity.v4l.minor = vdev->minor;
	200	#endif
2096a5dc	201	}
2096a5dc LP	202	return 0;
	203	}
	204	EXPORT_SYMBOL_GPL(v4l2_device_register_subdev_nodes);
	205
2a1fcdf0 HV	206	void v4l2_device_unregister_subdev(struct v4l2_subdev *sd)
2a1fcdf0 HV	207	{
61f5db54 LP	208	struct v4l2_device *v4l2_dev;
61f5db54 LP	209
2a1fcdf0	210	/* return if it isn't registered */
b0167600	211	if (sd == NULL \|\| sd->v4l2_dev == NULL)
2a1fcdf0	212	return;
2096a5dc	213
61f5db54 LP	214	v4l2_dev = sd->v4l2_dev;
	215
	216	spin_lock(&v4l2_dev->lock);
2a1fcdf0	217	list_del(&sd->list);
61f5db54 LP	218	spin_unlock(&v4l2_dev->lock);
61f5db54 LP	219
45f6f84a HV	220	if (sd->internal_ops && sd->internal_ops->unregistered)
45f6f84a HV	221	sd->internal_ops->unregistered(sd);
b0167600	222	sd->v4l2_dev = NULL;
2096a5dc	223
61f5db54 LP	224	#if defined(CONFIG_MEDIA_CONTROLLER)
	225	if (v4l2_dev->mdev)
	226	media_device_unregister_entity(&sd->entity);
	227	#endif
2096a5dc	228	video_unregister_device(&sd->devnode);
2a1fcdf0 HV	229	module_put(sd->owner);
	230	}
	231	EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev);