164 lines
		
	
	
		
			3.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			164 lines
		
	
	
		
			3.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
 | 
						|
 * drivers/media/video/v4l2-int-device.c
 | 
						|
 *
 | 
						|
 * V4L2 internal ioctl interface.
 | 
						|
 *
 | 
						|
 * Copyright (C) 2007 Nokia Corporation.
 | 
						|
 *
 | 
						|
 * Contact: Sakari Ailus <sakari.ailus@nokia.com>
 | 
						|
 *
 | 
						|
 * 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., 51 Franklin St, Fifth Floor, Boston, MA
 | 
						|
 * 02110-1301 USA
 | 
						|
 */
 | 
						|
 | 
						|
#include <linux/kernel.h>
 | 
						|
#include <linux/list.h>
 | 
						|
#include <linux/sort.h>
 | 
						|
#include <linux/string.h>
 | 
						|
 | 
						|
#include <media/v4l2-int-device.h>
 | 
						|
 | 
						|
static DEFINE_MUTEX(mutex);
 | 
						|
static LIST_HEAD(int_list);
 | 
						|
 | 
						|
void v4l2_int_device_try_attach_all(void)
 | 
						|
{
 | 
						|
	struct v4l2_int_device *m, *s;
 | 
						|
 | 
						|
	list_for_each_entry(m, &int_list, head) {
 | 
						|
		if (m->type != v4l2_int_type_master)
 | 
						|
			continue;
 | 
						|
 | 
						|
		list_for_each_entry(s, &int_list, head) {
 | 
						|
			if (s->type != v4l2_int_type_slave)
 | 
						|
				continue;
 | 
						|
 | 
						|
			/* Slave is connected? */
 | 
						|
			if (s->u.slave->master)
 | 
						|
				continue;
 | 
						|
 | 
						|
			/* Slave wants to attach to master? */
 | 
						|
			if (s->u.slave->attach_to[0] != 0
 | 
						|
			    && strncmp(m->name, s->u.slave->attach_to,
 | 
						|
				       V4L2NAMESIZE))
 | 
						|
				continue;
 | 
						|
 | 
						|
			if (!try_module_get(m->module))
 | 
						|
				continue;
 | 
						|
 | 
						|
			s->u.slave->master = m;
 | 
						|
			if (m->u.master->attach(s)) {
 | 
						|
				s->u.slave->master = NULL;
 | 
						|
				module_put(m->module);
 | 
						|
				continue;
 | 
						|
			}
 | 
						|
		}
 | 
						|
	}
 | 
						|
}
 | 
						|
EXPORT_SYMBOL_GPL(v4l2_int_device_try_attach_all);
 | 
						|
 | 
						|
static int ioctl_sort_cmp(const void *a, const void *b)
 | 
						|
{
 | 
						|
	const struct v4l2_int_ioctl_desc *d1 = a, *d2 = b;
 | 
						|
 | 
						|
	if (d1->num > d2->num)
 | 
						|
		return 1;
 | 
						|
 | 
						|
	if (d1->num < d2->num)
 | 
						|
		return -1;
 | 
						|
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
int v4l2_int_device_register(struct v4l2_int_device *d)
 | 
						|
{
 | 
						|
	if (d->type == v4l2_int_type_slave)
 | 
						|
		sort(d->u.slave->ioctls, d->u.slave->num_ioctls,
 | 
						|
		     sizeof(struct v4l2_int_ioctl_desc),
 | 
						|
		     &ioctl_sort_cmp, NULL);
 | 
						|
	mutex_lock(&mutex);
 | 
						|
	list_add(&d->head, &int_list);
 | 
						|
	v4l2_int_device_try_attach_all();
 | 
						|
	mutex_unlock(&mutex);
 | 
						|
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
EXPORT_SYMBOL_GPL(v4l2_int_device_register);
 | 
						|
 | 
						|
void v4l2_int_device_unregister(struct v4l2_int_device *d)
 | 
						|
{
 | 
						|
	mutex_lock(&mutex);
 | 
						|
	list_del(&d->head);
 | 
						|
	if (d->type == v4l2_int_type_slave
 | 
						|
	    && d->u.slave->master != NULL) {
 | 
						|
		d->u.slave->master->u.master->detach(d);
 | 
						|
		module_put(d->u.slave->master->module);
 | 
						|
		d->u.slave->master = NULL;
 | 
						|
	}
 | 
						|
	mutex_unlock(&mutex);
 | 
						|
}
 | 
						|
EXPORT_SYMBOL_GPL(v4l2_int_device_unregister);
 | 
						|
 | 
						|
/* Adapted from search_extable in extable.c. */
 | 
						|
static v4l2_int_ioctl_func *find_ioctl(struct v4l2_int_slave *slave, int cmd,
 | 
						|
				       v4l2_int_ioctl_func *no_such_ioctl)
 | 
						|
{
 | 
						|
	const struct v4l2_int_ioctl_desc *first = slave->ioctls;
 | 
						|
	const struct v4l2_int_ioctl_desc *last =
 | 
						|
		first + slave->num_ioctls - 1;
 | 
						|
 | 
						|
	while (first <= last) {
 | 
						|
		const struct v4l2_int_ioctl_desc *mid;
 | 
						|
 | 
						|
		mid = (last - first) / 2 + first;
 | 
						|
 | 
						|
		if (mid->num < cmd)
 | 
						|
			first = mid + 1;
 | 
						|
		else if (mid->num > cmd)
 | 
						|
			last = mid - 1;
 | 
						|
		else
 | 
						|
			return mid->func;
 | 
						|
	}
 | 
						|
 | 
						|
	return no_such_ioctl;
 | 
						|
}
 | 
						|
 | 
						|
static int no_such_ioctl_0(struct v4l2_int_device *d)
 | 
						|
{
 | 
						|
	return -ENOIOCTLCMD;
 | 
						|
}
 | 
						|
 | 
						|
int v4l2_int_ioctl_0(struct v4l2_int_device *d, int cmd)
 | 
						|
{
 | 
						|
	return ((v4l2_int_ioctl_func_0 *)
 | 
						|
		find_ioctl(d->u.slave, cmd,
 | 
						|
			   (v4l2_int_ioctl_func *)no_such_ioctl_0))(d);
 | 
						|
}
 | 
						|
EXPORT_SYMBOL_GPL(v4l2_int_ioctl_0);
 | 
						|
 | 
						|
static int no_such_ioctl_1(struct v4l2_int_device *d, void *arg)
 | 
						|
{
 | 
						|
	return -ENOIOCTLCMD;
 | 
						|
}
 | 
						|
 | 
						|
int v4l2_int_ioctl_1(struct v4l2_int_device *d, int cmd, void *arg)
 | 
						|
{
 | 
						|
	return ((v4l2_int_ioctl_func_1 *)
 | 
						|
		find_ioctl(d->u.slave, cmd,
 | 
						|
			   (v4l2_int_ioctl_func *)no_such_ioctl_1))(d, arg);
 | 
						|
}
 | 
						|
EXPORT_SYMBOL_GPL(v4l2_int_ioctl_1);
 | 
						|
 | 
						|
MODULE_LICENSE("GPL");
 |