path: root/drivers/media/usb/cpia2/cpia2_v4l.c

/****************************************************************************
 *
 *  Filename: cpia2_v4l.c
 *
 *  Copyright 2001, STMicrolectronics, Inc.
 *      Contact:  steve.miller@st.com
 *  Copyright 2001,2005, Scott J. Bertin <scottbertin@yahoo.com>
 *
 *  Description:
 *     This is a USB driver for CPia2 based video cameras.
 *     The infrastructure of this driver is based on the cpia usb driver by
 *     Jochen Scharrlach and Johannes Erdfeldt.
 *
 *  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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *  Stripped of 2.4 stuff ready for main kernel submit by
 *		Alan Cox <alan@lxorguk.ukuu.org.uk>
 ****************************************************************************/

#define CPIA_VERSION "3.0.1"

#include <linux/module.h>
#include <linux/time.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/videodev2.h>
#include <linux/stringify.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-event.h>

#include "cpia2.h"

static int video_nr = -1;
module_param(video_nr, int, 0);
MODULE_PARM_DESC(video_nr, "video device to register (0=/dev/video0, etc)");

static int buffer_size = 68 * 1024;
module_param(buffer_size, int, 0);
MODULE_PARM_DESC(buffer_size, "Size for each frame buffer in bytes (default 68k)");

static int num_buffers = 3;
module_param(num_buffers, int, 0);
MODULE_PARM_DESC(num_buffers, "Number of frame buffers (1-"
		 __stringify(VIDEO_MAX_FRAME) ", default 3)");

static int alternate = DEFAULT_ALT;
module_param(alternate, int, 0);
MODULE_PARM_DESC(alternate, "USB Alternate (" __stringify(USBIF_ISO_1) "-"
		 __stringify(USBIF_ISO_6) ", default "
		 __stringify(DEFAULT_ALT) ")");

static int flicker_mode;
module_param(flicker_mode, int, 0);
MODULE_PARM_DESC(flicker_mode, "Flicker frequency (0 (disabled), " __stringify(50) " or "
		 __stringify(60) ", default 0)");

MODULE_AUTHOR("Steve Miller (STMicroelectronics) <steve.miller@st.com>");
MODULE_DESCRIPTION("V4L-driver for STMicroelectronics CPiA2 based cameras");
MODULE_SUPPORTED_DEVICE("video");
MODULE_LICENSE("GPL");
MODULE_VERSION(CPIA_VERSION);

#define ABOUT "V4L-Driver for Vision CPiA2 based cameras"
#define CPIA2_CID_USB_ALT (V4L2_CID_USER_BASE | 0xf000)

/******************************************************************************
 *
 *  cpia2_open
 *
 *****************************************************************************/
static int cpia2_open(struct file *file)
{
	struct camera_data *cam = video_drvdata(file);
	int retval;

	if (mutex_lock_interruptible(&cam->v4l2_lock))
		return -ERESTARTSYS;
	retval = v4l2_fh_open(file);
	if (retval)
		goto open_unlock;

	if (v4l2_fh_is_singular_file(file)) {
		if (cpia2_allocate_buffers(cam)) {
			v4l2_fh_release(file);
			retval = -ENOMEM;
			goto open_unlock;
		}

		/* reset the camera */
		if (cpia2_reset_camera(cam) < 0) {
			v4l2_fh_release(file