text: // SPDX-License-Identifier: GPL-2.0-or-later
  /*
   * USB USBVISION Video device driver 0.9.10
   *
   * Copyright (c) 1999-2005 Joerg Heckenbach <joerg@heckenbach-aw.de>
   *
   * This module is part of usbvision driver project.
   *
   * Let's call the version 0.... until compression decoding is completely
   * implemented.
   *
   * This driver is written by Jose Ignacio Gijon and Joerg Heckenbach.
   * It was based on USB CPiA driver written by Peter Pregler,
   * Scott J. Bertin and Johannes Erdfelt
   * Ideas are taken from bttv driver by Ralph Metzler, Marcus Metzler &
   * Gerd Knorr and zoran 36120/36125 driver by Pauline Middelink
   * Updates to driver completed by Dwaine P. Garden
   *
   * TODO:
   *     - use submit_urb for all setup packets
   *     - Fix memory settings for nt1004. It is 4 times as big as the
   *       nt1003 memory.
   *     - Add audio on endpoint 3 for nt1004 chip.
   *         Seems impossible, needs a codec interface.  Which one?
   *     - Clean up the driver.
   *     - optimization for performance.
   *     - Add Videotext capability (VBI).  Working on it.....
   *     - Check audio for other devices
   */
  
  #include <linux/kernel.h>
  #include <linux/list.h>
  #include <linux/timer.h>
  #include <linux/slab.h>
  #include <linux/mm.h>
  #include <linux/highmem.h>
  #include <linux/vmalloc.h>
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/spinlock.h>
  #include <linux/io.h>
  #include <linux/videodev2.h>
  #include <linux/i2c.h>
  
  #include <media/i2c/saa7115.h>
  #include <media/v4l2-common.h>
  #include <media/v4l2-ioctl.h>
  #include <media/v4l2-event.h>
  #include <media/tuner.h>
  
  #include <linux/workqueue.h>
  
  #include "usbvision.h"
  #include "usbvision-cards.h"
  
  #define DRIVER_AUTHOR					\
  	"Joerg Heckenbach <joerg@heckenbach-aw.de>, "	\
  	"Dwaine Garden <DwaineGarden@rogers.com>"
  #define DRIVER_NAME "usbvision"
  #define DRIVER_ALIAS "USBVision"
  #define DRIVER_DESC "USBVision USB Video Device Driver for Linux"
  #define USBVISION_VERSION_STRING "0.9.11"
  
  #define	ENABLE_HEXDUMP	0	/* Enable if you need it */
  
  
  #ifdef USBVISION_DEBUG
  	#define PDEBUG(level, fmt, args...) { \
  		if (video_debug & (level)) \
  			printk(KERN_INFO KBUILD_MODNAME ":[%s:%d] " fmt, \
  				__func__, __LINE__ , ## args); \
  	}
  #else
  	#define PDEBUG(level, fmt, args...) do {} while (0)
  #endif
  
  #define DBG_IO		(1 << 1)
  #define DBG_PROBE	(1 << 2)
  #define DBG_MMAP	(1 << 3)
  
  /* String operations */
  #define rmspace(str)	while (*str == ' ') str++;
  #define goto2next(str)	while (*str != ' ') str++; while (*str == ' ') str++;
  
  
  /* sequential number of usbvision device */
  static int usbvision_nr;
  
  static struct usbvision_v4l2_format_st usbvision_v4l2_format[] = {
  	{ 1, 1,  8, V4L2_PIX_FMT_GREY },
  	{ 1, 2, 16, V4L2_PIX_FMT_RGB565 },
  	{ 1, 3, 24, V4L2_PIX_FMT_RGB24 },
  	{ 1, 4, 32, V4L2_PIX_FMT_RGB32 },
  	{ 1, 2, 16, V4L2_PIX_FMT_RGB555 },
  	{ 1, 2, 16, V4L2_PIX_FMT_YUYV },
  	{ 1, 2, 12, V4L2_PIX_FMT_YVU420 }, /* 1.5 ! */
  	{ 1, 2, 16, V4L2_PIX_FMT_YUV422P }
  };
  
  /* Function prototypes */
  static void usbvision_release(struct usb_usbvision *usbvision);
  
  /* Default initialization of device driver parameters */
  /* Set the default format for ISOC endpoint */
  static int isoc_mode = ISOC_MODE_COMPRESS;
  /* Set the default Debug Mode of the device driver */
  static int video_debug;
  /* Sequential Number of Video Device */
  static int video_nr = -1;
  /* Sequential Number of Radio Device */
  static int radio_nr = -1;
  
  /* Grab parameters for the device driver */
  
  /* Showing parameters under SYSFS */
  module_param(isoc_mode, int, 0444);
  module_param(video_debug, int, 0444);
  module_param(video_nr, int, 0444);
  module_param(radio_nr, int, 0444);
  
  MODULE_PARM_DESC(isoc_mode, " Set the default format for ISOC endpoint.  Default: 0x60 (Compression On)");
  MODULE_PARM_DESC(video_debug, " Set the default Debug Mode of the device driver.  Default: 0 (Off)");
  MODULE_PARM_DESC(video_nr, "Set video device number (/dev/videoX).  Default: -1 (autodetect)");
  MODULE_PARM_DESC(radio_nr, "Set radio device number (/dev/radioX).  Default: -1 (autodetect)");
  
  
  /* Misc stuff */
  MODULE_AUTHOR(DRIVER_AUTHOR);
  MODULE_DESCRIPTION(DRIVER_DESC);
  MODULE_LICENSE("GPL");
  MODULE_VERSION(USBVISION_VERSION_STRING);
  MODULE_ALIAS(DRIVER_ALIAS);
  
  
  /*****************************************************************************/
  /* SYSFS Code - Copied from the stv680.c usb module.			     */
  /* Device information is located at /sys/class/video4linux/video0            */
  /* Device parameters information is located at /sys/module/usbvision         */
  /* Device USB Information is located at                                      */
  /*   /sys/bus/usb/drivers/USBVision Video Grabber                            */
  /*****************************************************************************/
  
  #define YES_NO(x) ((x) ? "Yes" : "No")
  
  static inline struct usb_usbvision *cd_to_usbvision(struct device *cd)
  {
  	struct video_device *vdev = to_video_device(cd);
  	return video_get_drvdata(vdev);
  }
  
  static ssize_t show_version(struct device *cd,
  			    struct device_attribute *attr, char *buf)
  {
  	return sprintf(buf, "%s\n", USBVISION_VERSION_STRING);
  }
  static DEVICE_ATTR(version, S_IRUGO, show_version, NULL);
  
  static ssize_t show_model(struct device *cd,
  			  struct device_attribute *attr, char *buf)
  {
  	struct video_device *vdev = to_video_device(cd);
  	struct usb_usbvision *usbvision = video_get_drvdata(vdev);
  	return sprintf(buf, "%s\n",
  		       usbvision_device_data[usbvision->dev_model].model_string);
  }
  static DEVICE_ATTR(model, S_IRUGO, show_model, NULL);
  
  static ssize_t show_hue(struct device *cd,
  			struct device_attribute *attr, char *buf)
  {
  	struct video_device *vdev = to_video_device(cd);
  	struct usb_usbvision *usbvision = video_get_drvdata(vdev);
  	s32 val = v4l2_ctrl_g_ctrl(v4l2_ctrl_find(&usbvision->hdl,
  						  V4L2_CID_HUE));
  
  	return sprintf(buf, "%d\n", val);
  }
  static DEVICE_ATTR(hue, S_IRUGO, show_hue, NULL);
  
  static ssize_t show_contrast(struct device *cd,
  			     struct device_attribute *attr, char *buf)
  {
  	struct video_device *vdev = to_video_device(cd);
  	struct usb_usbvision *usbvision = video_get_drvdata(vdev);
  	s32 val = v4l2_ctrl_g_ctrl(v4l2_ctrl_find(&usbvision->hdl,
  						  V4L2_CID_CONTRAST));
  
  	return sprintf(buf, "%d\n", val);
  }
  static DEVICE_ATTR(contrast, S_IRUGO, show_contrast, NULL);
  
  static ssize_t show_brightness(struct device *cd,
  			       struct device_attribute *attr, char *buf)
  {
  	struct video_device *vdev = to_video_device(cd);
  	struct usb_usbvision *usbvision = video_get_drvdata(vdev);
  	s32 val = v4l2_ctrl_g_ctrl(v4l2_ctrl_find(&usbvision->hdl,
  						  V4L2_CID_BRIGHTNESS));
  
  	return sprintf(buf, "%d\n", val);
  }
  static DEVICE_ATTR(brightness, S_IRUGO, show_brightness, NULL);
  
  static ssize_t show_saturation(struct device *cd,
  			       struct device_attribute *attr, char *buf)
  {
  	struct video_device *vdev = to_video_device(cd);
  	struct usb_usbvision *usbvision = video_get_drvdata(vdev);
  	s32 val = v4l2_ctrl_g_ctrl(v4l2_ctrl_find(&usbvision->hdl,
  						  V4L2_CID_SATURATION));
  
  	return sprintf(buf, "%d\n", val);
  }
  static DEVICE_ATTR(saturation, S_IRUGO, show_saturation, NULL);
  
  static ssize_t show_streaming(struct device *cd,
  			      struct device_attribute *attr, char *buf)
  {
  	struct video_device *vdev = to_video_device(cd);
  	struct usb_usbvision *usbvision = video_get_drvdata(vdev);
  	return sprintf(buf, "%s\n",
  		       YES_NO(usbvision->streaming == stream_on ? 1 : 0));
  }
  static DEVICE_ATTR(streaming, S_IRUGO, show_streaming, NULL);
  
  static ssize_t show_compression(struct device *cd,
  				struct device_attribute *attr, char *buf)
  {
  	struct video_device *vdev = to_video_device(cd);
  	struct usb_usbvision *usbvision = video_get_drvdata(vdev);
  	return sprintf(buf, "%s\n",
  		       YES_NO(usbvision->isoc_mode == ISOC_MODE_COMPRESS));
  }
  static DEVICE_ATTR(compression, S_IRUGO, show_compression, NULL);
  
  static ssize_t show_device_bridge(struct device *cd,
  				  struct device_attribute *attr, char *buf)
  {
  	struct video_device *vdev = to_video_device(cd);
  	struct usb_usbvision *usbvision = video_get_drvdata(vdev);
  	return sprintf(buf, "%d\n", usbvision->bridge_type);
  }
  static DEVICE_ATTR(bridge, S_IRUGO, show_device_bridge, NULL);
  
  static void usbvision_create_sysfs(struct video_device *vdev)
  {
  	int res;
  
  	if (!vdev)
  		return;
  	do {
  		res = device_create_file(&vdev->dev, &dev_attr_version);
  		if (res < 0)
  			break;
  		res = device_create_file(&vdev->dev, &dev_attr_model);
  		if (res < 0)
  			break;
  		res = device_create_file(&vdev->dev, &dev_attr_hue);
  		if (res < 0)
  			break;
  		res = device_create_file(&vdev->dev, &dev_attr_contrast);
  		if (res < 0)
  			break;
  		res = device_create_file(&vdev->dev, &dev_attr_brightness);
  		if (res < 0)
  			break;
  		res = device_create_file(&vdev->dev, &dev_attr_saturation);
  		if (res < 0)
  			break;
  		res = device_create_file(&vdev->dev, &dev_attr_streaming);
  		if (res < 0)
  			break;
  		res = device_create_file(&vdev->dev, &dev_attr_compression);
  		if (res < 0)
  			break;
  		res = device_create_file(&vdev->dev, &dev_attr_bridge);
  		if (res >= 0)
  			return;
  	} while (0);
  
  	dev_err(&vdev->dev, "%s error: %d\n", __func__, res);
  }
  
  static void usbvision_remove_sysfs(struct video_device *vdev)
  {
  	if (vdev) {
  		device_remove_file(&vdev->dev, &dev_attr_version);
  		device_remove_file(&vdev->dev, &dev_attr_model);
  		device_remove_file(&vdev->dev, &dev_attr_hue);
  		device_remove_file(&vdev->dev, &dev_attr_contrast);
  		device_remove_file(&vdev->dev, &dev_attr_brightness);
  		device_remove_file(&vdev->dev, &dev_attr_saturation);
  		device_remove_file(&vdev->dev, &dev_attr_streaming);
  		device_remove_file(&vdev->dev, &dev_attr_compression);
  		device_remove_file(&vdev->dev, &dev_attr_bridge);
  	}
  }
  
  /*
   * usbvision_open()
   *
   * This is part of Video 4 Linux API. The driver can be opened by one
   * client only (checks internal counter 'usbvision->user'). The procedure
   * then allocates buffers needed for video processing.
   *
   */
  static int usbvision_v4l2_open(struct file *file)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  	int err_code = 0;
  
  	PDEBUG(DBG_IO, "open");
  
  	if (mutex_lock_interruptible(&usbvision->v4l2_lock))
  		return -ERESTARTSYS;
  
  	if (usbvision->user) {
  		err_code = -EBUSY;
  	} else {
  		err_code = v4l2_fh_open(file);
  		if (err_code)
  			goto unlock;
  
  		/* Allocate memory for the scratch ring buffer */
  		err_code = usbvision_scratch_alloc(usbvision);
  		if (isoc_mode == ISOC_MODE_COMPRESS) {
  			/* Allocate intermediate decompression buffers
  			   only if needed */
  			err_code = usbvision_decompress_alloc(usbvision);
  		}
  		if (err_code) {
  			/* Deallocate all buffers if trouble */
  			usbvision_scratch_free(usbvision);
  			usbvision_decompress_free(usbvision);
  		}
  	}
  
  	/* If so far no errors then we shall start the camera */
  	if (!err_code) {
  		/* Send init sequence only once, it's large! */
  		if (!usbvision->initialized) {
  			int setup_ok = 0;
  			setup_ok = usbvision_setup(usbvision, isoc_mode);
  			if (setup_ok)
  				usbvision->initialized = 1;
  			else
  				err_code = -EBUSY;
  		}
  
  		if (!err_code) {
  			usbvision_begin_streaming(usbvision);
  			err_code = usbvision_init_isoc(usbvision);
  			/* device must be initialized before isoc transfer */
  			usbvision_muxsel(usbvision, 0);
  
  			/* prepare queues */
  			usbvision_empty_framequeues(usbvision);
  			usbvision->user++;
  		}
  	}
  
  unlock:
  	mutex_unlock(&usbvision->v4l2_lock);
  
  	PDEBUG(DBG_IO, "success");
  	return err_code;
  }
  
  /*
   * usbvision_v4l2_close()
   *
   * This is part of Video 4 Linux API. The procedure
   * stops streaming and deallocates all buffers that were earlier
   * allocated in usbvision_v4l2_open().
   *
   */
  static int usbvision_v4l2_close(struct file *file)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  
  	PDEBUG(DBG_IO, "close");
  
  	mutex_lock(&usbvision->v4l2_lock);
  	usbvision_audio_off(usbvision);
  	usbvision_restart_isoc(usbvision);
  	usbvision_stop_isoc(usbvision);
  
  	usbvision_decompress_free(usbvision);
  	usbvision_frames_free(usbvision);
  	usbvision_empty_framequeues(usbvision);
  	usbvision_scratch_free(usbvision);
  
  	usbvision->user--;
  	mutex_unlock(&usbvision->v4l2_lock);
  
  	if (usbvision->remove_pending) {
  		printk(KERN_INFO "%s: Final disconnect\n", __func__);
  		usbvision_release(usbvision);
  		return 0;
  	}
  
  	PDEBUG(DBG_IO, "success");
  	return v4l2_fh_release(file);
  }
  
  
  /*
   * usbvision_ioctl()
   *
   * This is part of Video 4 Linux API. The procedure handles ioctl() calls.
   *
   */
  #ifdef CONFIG_VIDEO_ADV_DEBUG
  static int vidioc_g_register(struct file *file, void *priv,
  				struct v4l2_dbg_register *reg)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  	int err_code;
  
  	/* NT100x has a 8-bit register space */
  	err_code = usbvision_read_reg(usbvision, reg->reg&0xff);
  	if (err_code < 0) {
  		dev_err(&usbvision->vdev.dev,
  			"%s: VIDIOC_DBG_G_REGISTER failed: error %d\n",
  				__func__, err_code);
  		return err_code;
  	}
  	reg->val = err_code;
  	reg->size = 1;
  	return 0;
  }
  
  static int vidioc_s_register(struct file *file, void *priv,
  				const struct v4l2_dbg_register *reg)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  	int err_code;
  
  	/* NT100x has a 8-bit register space */
  	err_code = usbvision_write_reg(usbvision, reg->reg & 0xff, reg->val);
  	if (err_code < 0) {
  		dev_err(&usbvision->vdev.dev,
  			"%s: VIDIOC_DBG_S_REGISTER failed: error %d\n",
  				__func__, err_code);
  		return err_code;
  	}
  	return 0;
  }
  #endif
  
  static int vidioc_querycap(struct file *file, void  *priv,
  					struct v4l2_capability *vc)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  
  	strscpy(vc->driver, "USBVision", sizeof(vc->driver));
  	strscpy(vc->card,
  		usbvision_device_data[usbvision->dev_model].model_string,
  		sizeof(vc->card));
  	usb_make_path(usbvision->dev, vc->bus_info, sizeof(vc->bus_info));
  	vc->capabilities = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_READWRITE |
  			   V4L2_CAP_STREAMING | V4L2_CAP_DEVICE_CAPS;
  	if (usbvision_device_data[usbvision->dev_model].radio)
  		vc->capabilities |= V4L2_CAP_RADIO;
  	if (usbvision->have_tuner)
  		vc->capabilities |= V4L2_CAP_TUNER;
  	return 0;
  }
  
  static int vidioc_enum_input(struct file *file, void *priv,
  				struct v4l2_input *vi)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  	int chan;
  
  	if (vi->index >= usbvision->video_inputs)
  		return -EINVAL;
  	if (usbvision->have_tuner)
  		chan = vi->index;
  	else
  		chan = vi->index + 1; /* skip Television string*/
  
  	/* Determine the requested input characteristics
  	   specific for each usbvision card model */
  	switch (chan) {
  	case 0:
  		if (usbvision_device_data[usbvision->dev_model].video_channels == 4) {
  			strscpy(vi->name, "White Video Input", sizeof(vi->name));
  		} else {
  			strscpy(vi->name, "Television", sizeof(vi->name));
  			vi->type = V4L2_INPUT_TYPE_TUNER;
  			vi->tuner = chan;
  			vi->std = USBVISION_NORMS;
  		}
  		break;
  	case 1:
  		vi->type = V4L2_INPUT_TYPE_CAMERA;
  		if (usbvision_device_data[usbvision->dev_model].video_channels == 4)
  			strscpy(vi->name, "Green Video Input", sizeof(vi->name));
  		else
  			strscpy(vi->name, "Composite Video Input",
  				sizeof(vi->name));
  		vi->std = USBVISION_NORMS;
  		break;
  	case 2:
  		vi->type = V4L2_INPUT_TYPE_CAMERA;
  		if (usbvision_device_data[usbvision->dev_model].video_channels == 4)
  			strscpy(vi->name, "Yellow Video Input", sizeof(vi->name));
  		else
  			strscpy(vi->name, "S-Video Input", sizeof(vi->name));
  		vi->std = USBVISION_NORMS;
  		break;
  	case 3:
  		vi->type = V4L2_INPUT_TYPE_CAMERA;
  		strscpy(vi->name, "Red Video Input", sizeof(vi->name));
  		vi->std = USBVISION_NORMS;
  		break;
  	}
  	return 0;
  }
  
  static int vidioc_g_input(struct file *file, void *priv, unsigned int *input)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  
  	*input = usbvision->ctl_input;
  	return 0;
  }
  
  static int vidioc_s_input(struct file *file, void *priv, unsigned int input)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  
  	if (input >= usbvision->video_inputs)
  		return -EINVAL;
  
  	usbvision_muxsel(usbvision, input);
  	usbvision_set_input(usbvision);
  	usbvision_set_output(usbvision,
  			     usbvision->curwidth,
  			     usbvision->curheight);
  	return 0;
  }
  
  static int vidioc_s_std(struct file *file, void *priv, v4l2_std_id id)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  
  	usbvision->tvnorm_id = id;
  
  	call_all(usbvision, video, s_std, usbvision->tvnorm_id);
  	/* propagate the change to the decoder */
  	usbvision_muxsel(usbvision, usbvision->ctl_input);
  
  	return 0;
  }
  
  static int vidioc_g_std(struct file *file, void *priv, v4l2_std_id *id)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  
  	*id = usbvision->tvnorm_id;
  	return 0;
  }
  
  static int vidioc_g_tuner(struct file *file, void *priv,
  				struct v4l2_tuner *vt)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  
  	if (vt->index)	/* Only tuner 0 */
  		return -EINVAL;
  	if (vt->type == V4L2_TUNER_RADIO)
  		strscpy(vt->name, "Radio", sizeof(vt->name));
  	else
  		strscpy(vt->name, "Television", sizeof(vt->name));
  
  	/* Let clients fill in the remainder of this struct */
  	call_all(usbvision, tuner, g_tuner, vt);
  
  	return 0;
  }
  
  static int vidioc_s_tuner(struct file *file, void *priv,
  				const struct v4l2_tuner *vt)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  
  	/* Only one tuner for now */
  	if (vt->index)
  		return -EINVAL;
  	/* let clients handle this */
  	call_all(usbvision, tuner, s_tuner, vt);
  
  	return 0;
  }
  
  static int vidioc_g_frequency(struct file *file, void *priv,
  				struct v4l2_frequency *freq)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  
  	/* Only one tuner */
  	if (freq->tuner)
  		return -EINVAL;
  	if (freq->type == V4L2_TUNER_RADIO)
  		freq->frequency = usbvision->radio_freq;
  	else
  		freq->frequency = usbvision->tv_freq;
  
  	return 0;
  }
  
  static int vidioc_s_frequency(struct file *file, void *priv,
  				const struct v4l2_frequency *freq)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  	struct v4l2_frequency new_freq = *freq;
  
  	/* Only one tuner for now */
  	if (freq->tuner)
  		return -EINVAL;
  
  	call_all(usbvision, tuner, s_frequency, freq);
  	call_all(usbvision, tuner, g_frequency, &new_freq);
  	if (freq->type == V4L2_TUNER_RADIO)
  		usbvision->radio_freq = new_freq.frequency;
  	else
  		usbvision->tv_freq = new_freq.frequency;
  
  	return 0;
  }
  
  static int vidioc_reqbufs(struct file *file,
  			   void *priv, struct v4l2_requestbuffers *vr)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  	int ret;
  
  	RESTRICT_TO_RANGE(vr->count, 1, USBVISION_NUMFRAMES);
  
  	/* Check input validity:
  	   the user must do a VIDEO CAPTURE and MMAP method. */
  	if (vr->memory != V4L2_MEMORY_MMAP)
  		return -EINVAL;
  
  	if (usbvision->streaming == stream_on) {
  		ret = usbvision_stream_interrupt(usbvision);
  		if (ret)
  			return ret;
  	}
  
  	usbvision_frames_free(usbvision);
  	usbvision_empty_framequeues(usbvision);
  	vr->count = usbvision_frames_alloc(usbvision, vr->count);
  
  	usbvision->cur_frame = NULL;
  
  	return 0;
  }
  
  static int vidioc_querybuf(struct file *file,
  			    void *priv, struct v4l2_buffer *vb)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  	struct usbvision_frame *frame;
  
  	/* FIXME : must control
  	   that buffers are mapped (VIDIOC_REQBUFS has been called) */
  	if (vb->index >= usbvision->num_frames)
  		return -EINVAL;
  	/* Updating the corresponding frame state */
  	vb->flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
  	frame = &usbvision->frame[vb->index];
  	if (frame->grabstate >= frame_state_ready)
  		vb->flags |= V4L2_BUF_FLAG_QUEUED;
  	if (frame->grabstate >= frame_state_done)
  		vb->flags |= V4L2_BUF_FLAG_DONE;
  	if (frame->grabstate == frame_state_unused)
  		vb->flags |= V4L2_BUF_FLAG_MAPPED;
  	vb->memory = V4L2_MEMORY_MMAP;
  
  	vb->m.offset = vb->index * PAGE_ALIGN(usbvision->max_frame_size);
  
  	vb->memory = V4L2_MEMORY_MMAP;
  	vb->field = V4L2_FIELD_NONE;
  	vb->length = usbvision->curwidth *
  		usbvision->curheight *
  		usbvision->palette.bytes_per_pixel;
  	vb->timestamp = ns_to_timeval(usbvision->frame[vb->index].ts);
  	vb->sequence = usbvision->frame[vb->index].sequence;
  	return 0;
  }
  
  static int vidioc_qbuf(struct file *file, void *priv, struct v4l2_buffer *vb)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  	struct usbvision_frame *frame;
  	unsigned long lock_flags;
  
  	/* FIXME : works only on VIDEO_CAPTURE MODE, MMAP. */
  	if (vb->index >= usbvision->num_frames)
  		return -EINVAL;
  
  	frame = &usbvision->frame[vb->index];
  
  	if (frame->grabstate != frame_state_unused)
  		return -EAGAIN;
  
  	/* Mark it as ready and enqueue frame */
  	frame->grabstate = frame_state_ready;
  	frame->scanstate = scan_state_scanning;
  	frame->scanlength = 0;	/* Accumulated in usbvision_parse_data() */
  
  	vb->flags &= ~V4L2_BUF_FLAG_DONE;
  
  	/* set v4l2_format index */
  	frame->v4l2_format = usbvision->palette;
  
  	spin_lock_irqsave(&usbvision->queue_lock, lock_flags);
  	list_add_tail(&usbvision->frame[vb->index].frame, &usbvision->inqueue);
  	spin_unlock_irqrestore(&usbvision->queue_lock, lock_flags);
  
  	return 0;
  }
  
  static int vidioc_dqbuf(struct file *file, void *priv, struct v4l2_buffer *vb)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  	int ret;
  	struct usbvision_frame *f;
  	unsigned long lock_flags;
  
  	if (list_empty(&(usbvision->outqueue))) {
  		if (usbvision->streaming == stream_idle)
  			return -EINVAL;
  		ret = wait_event_interruptible
  			(usbvision->wait_frame,
  			 !list_empty(&(usbvision->outqueue)));
  		if (ret)
  			return ret;
  	}
  
  	spin_lock_irqsave(&usbvision->queue_lock, lock_flags);
  	f = list_entry(usbvision->outqueue.next,
  		       struct usbvision_frame, frame);
  	list_del(usbvision->outqueue.next);
  	spin_unlock_irqrestore(&usbvision->queue_lock, lock_flags);
  
  	f->grabstate = frame_state_unused;
  
  	vb->memory = V4L2_MEMORY_MMAP;
  	vb->flags = V4L2_BUF_FLAG_MAPPED |
  		V4L2_BUF_FLAG_QUEUED |
  		V4L2_BUF_FLAG_DONE |
  		V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
  	vb->index = f->index;
  	vb->sequence = f->sequence;
  	vb->timestamp = ns_to_timeval(f->ts);
  	vb->field = V4L2_FIELD_NONE;
  	vb->bytesused = f->scanlength;
  
  	return 0;
  }
  
  static int vidioc_streamon(struct file *file, void *priv, enum v4l2_buf_type i)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  
  	usbvision->streaming = stream_on;
  	call_all(usbvision, video, s_stream, 1);
  
  	return 0;
  }
  
  static int vidioc_streamoff(struct file *file,
  			    void *priv, enum v4l2_buf_type type)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  
  	if (type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
  		return -EINVAL;
  
  	if (usbvision->streaming == stream_on) {
  		usbvision_stream_interrupt(usbvision);
  		/* Stop all video streamings */
  		call_all(usbvision, video, s_stream, 0);
  	}
  	usbvision_empty_framequeues(usbvision);
  
  	return 0;
  }
  
  static int vidioc_enum_fmt_vid_cap(struct file *file, void  *priv,
  					struct v4l2_fmtdesc *vfd)
  {
  	if (vfd->index >= USBVISION_SUPPORTED_PALETTES - 1)
  		return -EINVAL;
  	vfd->pixelformat = usbvision_v4l2_format[vfd->index].format;
  	return 0;
  }
  
  static int vidioc_g_fmt_vid_cap(struct file *file, void *priv,
  					struct v4l2_format *vf)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  	vf->fmt.pix.width = usbvision->curwidth;
  	vf->fmt.pix.height = usbvision->curheight;
  	vf->fmt.pix.pixelformat = usbvision->palette.format;
  	vf->fmt.pix.bytesperline =
  		usbvision->curwidth * usbvision->palette.bytes_per_pixel;
  	vf->fmt.pix.sizeimage = vf->fmt.pix.bytesperline * usbvision->curheight;
  	vf->fmt.pix.colorspace = V4L2_COLORSPACE_SMPTE170M;
  	vf->fmt.pix.field = V4L2_FIELD_NONE; /* Always progressive image */
  
  	return 0;
  }
  
  static int vidioc_try_fmt_vid_cap(struct file *file, void *priv,
  			       struct v4l2_format *vf)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  	int format_idx;
  
  	/* Find requested format in available ones */
  	for (format_idx = 0; format_idx < USBVISION_SUPPORTED_PALETTES; format_idx++) {
  		if (vf->fmt.pix.pixelformat ==
  		   usbvision_v4l2_format[format_idx].format) {
  			usbvision->palette = usbvision_v4l2_format[format_idx];
  			break;
  		}
  	}
  	/* robustness */
  	if (format_idx == USBVISION_SUPPORTED_PALETTES)
  		return -EINVAL;
  	RESTRICT_TO_RANGE(vf->fmt.pix.width, MIN_FRAME_WIDTH, MAX_FRAME_WIDTH);
  	RESTRICT_TO_RANGE(vf->fmt.pix.height, MIN_FRAME_HEIGHT, MAX_FRAME_HEIGHT);
  
  	vf->fmt.pix.bytesperline = vf->fmt.pix.width*
  		usbvision->palette.bytes_per_pixel;
  	vf->fmt.pix.sizeimage = vf->fmt.pix.bytesperline*vf->fmt.pix.height;
  	vf->fmt.pix.colorspace = V4L2_COLORSPACE_SMPTE170M;
  	vf->fmt.pix.field = V4L2_FIELD_NONE; /* Always progressive image */
  
  	return 0;
  }
  
  static int vidioc_s_fmt_vid_cap(struct file *file, void *priv,
  			       struct v4l2_format *vf)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  	int ret;
  
  	ret = vidioc_try_fmt_vid_cap(file, priv, vf);
  	if (ret)
  		return ret;
  
  	/* stop io in case it is already in progress */
  	if (usbvision->streaming == stream_on) {
  		ret = usbvision_stream_interrupt(usbvision);
  		if (ret)
  			return ret;
  	}
  	usbvision_frames_free(usbvision);
  	usbvision_empty_framequeues(usbvision);
  
  	usbvision->cur_frame = NULL;
  
  	/* by now we are committed to the new data... */
  	usbvision_set_output(usbvision, vf->fmt.pix.width, vf->fmt.pix.height);
  
  	return 0;
  }
  
  static ssize_t usbvision_read(struct file *file, char __user *buf,
  		      size_t count, loff_t *ppos)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  	int noblock = file->f_flags & O_NONBLOCK;
  	unsigned long lock_flags;
  	int ret, i;
  	struct usbvision_frame *frame;
  
  	PDEBUG(DBG_IO, "%s: %ld bytes, noblock=%d", __func__,
  	       (unsigned long)count, noblock);
  
  	if (!USBVISION_IS_OPERATIONAL(usbvision) || !buf)
  		return -EFAULT;
  
  	/* This entry point is compatible with the mmap routines
  	   so that a user can do either VIDIOC_QBUF/VIDIOC_DQBUF
  	   to get frames or call read on the device. */
  	if (!usbvision->num_frames) {
  		/* First, allocate some frames to work with
  		   if this has not been done with VIDIOC_REQBUF */
  		usbvision_frames_free(usbvision);
  		usbvision_empty_framequeues(usbvision);
  		usbvision_frames_alloc(usbvision, USBVISION_NUMFRAMES);
  	}
  
  	if (usbvision->streaming != stream_on) {
  		/* no stream is running, make it running ! */
  		usbvision->streaming = stream_on;
  		call_all(usbvision, video, s_stream, 1);
  	}
  
  	/* Then, enqueue as many frames as possible
  	   (like a user of VIDIOC_QBUF would do) */
  	for (i = 0; i < usbvision->num_frames; i++) {
  		frame = &usbvision->frame[i];
  		if (frame->grabstate == frame_state_unused) {
  			/* Mark it as ready and enqueue frame */
  			frame->grabstate = frame_state_ready;
  			frame->scanstate = scan_state_scanning;
  			/* Accumulated in usbvision_parse_data() */
  			frame->scanlength = 0;
  
  			/* set v4l2_format index */
  			frame->v4l2_format = usbvision->palette;
  
  			spin_lock_irqsave(&usbvision->queue_lock, lock_flags);
  			list_add_tail(&frame->frame, &usbvision->inqueue);
  			spin_unlock_irqrestore(&usbvision->queue_lock,
  					       lock_flags);
  		}
  	}
  
  	/* Then try to steal a frame (like a VIDIOC_DQBUF would do) */
  	if (list_empty(&(usbvision->outqueue))) {
  		if (noblock)
  			return -EAGAIN;
  
  		ret = wait_event_interruptible
  			(usbvision->wait_frame,
  			 !list_empty(&(usbvision->outqueue)));
  		if (ret)
  			return ret;
  	}
  
  	spin_lock_irqsave(&usbvision->queue_lock, lock_flags);
  	frame = list_entry(usbvision->outqueue.next,
  			   struct usbvision_frame, frame);
  	list_del(usbvision->outqueue.next);
  	spin_unlock_irqrestore(&usbvision->queue_lock, lock_flags);
  
  	/* An error returns an empty frame */
  	if (frame->grabstate == frame_state_error) {
  		frame->bytes_read = 0;
  		return 0;
  	}
  
  	PDEBUG(DBG_IO, "%s: frmx=%d, bytes_read=%ld, scanlength=%ld",
  	       __func__,
  	       frame->index, frame->bytes_read, frame->scanlength);
  
  	/* copy bytes to user space; we allow for partials reads */
  	if ((count + frame->bytes_read) > (unsigned long)frame->scanlength)
  		count = frame->scanlength - frame->bytes_read;
  
  	if (copy_to_user(buf, frame->data + frame->bytes_read, count))
  		return -EFAULT;
  
  	frame->bytes_read += count;
  	PDEBUG(DBG_IO, "%s: {copy} count used=%ld, new bytes_read=%ld",
  	       __func__,
  	       (unsigned long)count, frame->bytes_read);
  
  	/*
  	 * FIXME:
  	 * For now, forget the frame if it has not been read in one shot.
  	 */
  	frame->bytes_read = 0;
  
  	/* Mark it as available to be used again. */
  	frame->grabstate = frame_state_unused;
  
  	return count;
  }
  
  static ssize_t usbvision_v4l2_read(struct file *file, char __user *buf,
  		      size_t count, loff_t *ppos)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  	int res;
  
  	if (mutex_lock_interruptible(&usbvision->v4l2_lock))
  		return -ERESTARTSYS;
  	res = usbvision_read(file, buf, count, ppos);
  	mutex_unlock(&usbvision->v4l2_lock);
  	return res;
  }
  
  static int usbvision_mmap(struct file *file, struct vm_area_struct *vma)
  {
  	unsigned long size = vma->vm_end - vma->vm_start,
  		start = vma->vm_start;
  	void *pos;
  	u32 i;
  	struct usb_usbvision *usbvision = video_drvdata(file);
  
  	PDEBUG(DBG_MMAP, "mmap");
  
  	if (!USBVISION_IS_OPERATIONAL(usbvision))
  		return -EFAULT;
  
  	if (!(vma->vm_flags & VM_WRITE) ||
  	    size != PAGE_ALIGN(usbvision->max_frame_size)) {
  		return -EINVAL;
  	}
  
  	for (i = 0; i < usbvision->num_frames; i++) {
  		if (((PAGE_ALIGN(usbvision->max_frame_size)*i) >> PAGE_SHIFT) ==
  		    vma->vm_pgoff)
  			break;
  	}
  	if (i == usbvision->num_frames) {
  		PDEBUG(DBG_MMAP,
  		       "mmap: user supplied mapping address is out of range");
  		return -EINVAL;
  	}
  
  	/* VM_IO is eventually going to replace PageReserved altogether */
  	vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
  
  	pos = usbvision->frame[i].data;
  	while (size > 0) {
  		if (vm_insert_page(vma, start, vmalloc_to_page(pos))) {
  			PDEBUG(DBG_MMAP, "mmap: vm_insert_page failed");
  			return -EAGAIN;
  		}
  		start += PAGE_SIZE;
  		pos += PAGE_SIZE;
  		size -= PAGE_SIZE;
  	}
  
  	return 0;
  }
  
  static int usbvision_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  	int res;
  
  	if (mutex_lock_interruptible(&usbvision->v4l2_lock))
  		return -ERESTARTSYS;
  	res = usbvision_mmap(file, vma);
  	mutex_unlock(&usbvision->v4l2_lock);
  	return res;
  }
  
  /*
   * Here comes the stuff for radio on usbvision based devices
   *
   */
  static int usbvision_radio_open(struct file *file)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  	int err_code = 0;
  
  	PDEBUG(DBG_IO, "%s:", __func__);
  
  	if (mutex_lock_interruptible(&usbvision->v4l2_lock))
  		return -ERESTARTSYS;
  	err_code = v4l2_fh_open(file);
  	if (err_code)
  		goto out;
  	if (usbvision->user) {
  		dev_err(&usbvision->rdev.dev,
  			"%s: Someone tried to open an already opened USBVision Radio!\n",
  				__func__);
  		err_code = -EBUSY;
  	} else {
  		/* Alternate interface 1 is is the biggest frame size */
  		err_code = usbvision_set_alternate(usbvision);
  		if (err_code < 0) {
  			usbvision->last_error = err_code;
  			err_code = -EBUSY;
  			goto out;
  		}
  
  		/* If so far no errors then we shall start the radio */
  		usbvision->radio = 1;
  		call_all(usbvision, tuner, s_radio);
  		usbvision_set_audio(usbvision, USBVISION_AUDIO_RADIO);
  		usbvision->user++;
  	}
  out:
  	mutex_unlock(&usbvision->v4l2_lock);
  	return err_code;
  }
  
  
  static int usbvision_radio_close(struct file *file)
  {
  	struct usb_usbvision *usbvision = video_drvdata(file);
  
  	PDEBUG(DBG_IO, "");
  
  	mutex_lock(&usbvision->v4l2_lock);
  	/* Set packet size to 0 */
  	usbvision->iface_alt = 0;
  	usb_set_interface(usbvision->dev, usbvision->iface,
  				    usbvision->iface_alt);
  
  	usbvision_audio_off(usbvision);
  	usbvision->radio = 0;
  	usbvision->user--;
  	mutex_unlock(&usbvision->v4l2_lock);
  
  	if (usbvision->remove_pending) {
  		printk(KERN_INFO "%s: Final disconnect\n", __func__);
  		v4l2_fh_release(file);
  		usbvision_release(usbvision);
  		return 0;
  	}
  
  	PDEBUG(DBG_IO, "success");
  	return v4l2_fh_release(file);
  }
  
  /* Video registration stuff */
  
  /* Video template */
  static const struct v4l2_file_operations usbvision_fops = {
  	.owner             = THIS_MODULE,
  	.open		= usbvision_v4l2_open,
  	.release	= usbvision_v4l2_close,
  	.read		= usbvision_v4l2_read,
  	.mmap		= usbvision_v4l2_mmap,
  	.unlocked_ioctl	= video_ioctl2,
  };
  
  static const struct v4l2_ioctl_ops usbvision_ioctl_ops = {
  	.vidioc_querycap      = vidioc_querycap,
  	.vidioc_enum_fmt_vid_cap  = vidioc_enum_fmt_vid_cap,
  	.vidioc_g_fmt_vid_cap     = vidioc_g_fmt_vid_cap,
  	.vidioc_try_fmt_vid_cap   = vidioc_try_fmt_vid_cap,
  	.vidioc_s_fmt_vid_cap     = vidioc_s_fmt_vid_cap,
  	.vidioc_reqbufs       = vidioc_reqbufs,
  	.vidioc_querybuf      = vidioc_querybuf,
  	.vidioc_qbuf          = vidioc_qbuf,
  	.vidioc_dqbuf         = vidioc_dqbuf,
  	.vidioc_s_std         = vidioc_s_std,
  	.vidioc_g_std         = vidioc_g_std,
  	.vidioc_enum_input    = vidioc_enum_input,
  	.vidioc_g_input       = vidioc_g_input,
  	.vidioc_s_input       = vidioc_s_input,
  	.vidioc_streamon      = vidioc_streamon,
  	.vidioc_streamoff     = vidioc_streamoff,
  	.vidioc_g_tuner       = vidioc_g_tuner,
  	.vidioc_s_tuner       = vidioc_s_tuner,
  	.vidioc_g_frequency   = vidioc_g_frequency,
  	.vidioc_s_frequency   = vidioc_s_frequency,
  	.vidioc_log_status    = v4l2_ctrl_log_status,
  	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
  	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
  #ifdef CONFIG_VIDEO_ADV_DEBUG
  	.vidioc_g_register    = vidioc_g_register,
  	.vidioc_s_register    = vidioc_s_register,
  #endif
  };
  
  static struct video_device usbvision_video_template = {
  	.fops		= &usbvision_fops,
  	.ioctl_ops	= &usbvision_ioctl_ops,
  	.name           = "usbvision-video",
  	.release	= video_device_release_empty,
  	.tvnorms        = USBVISION_NORMS,
  };
  
  
  /* Radio template */
  static const struct v4l2_file_operations usbvision_radio_fops = {
  	.owner             = THIS_MODULE,
  	.open		= usbvision_radio_open,
  	.release	= usbvision_radio_close,
  	.poll		= v4l2_ctrl_poll,
  	.unlocked_ioctl	= video_ioctl2,
  };
  
  static const struct v4l2_ioctl_ops usbvision_radio_ioctl_ops = {
  	.vidioc_querycap      = vidioc_querycap,
  	.vidioc_g_tuner       = vidioc_g_tuner,
  	.vidioc_s_tuner       = vidioc_s_tuner,
  	.vidioc_g_frequency   = vidioc_g_frequency,
  	.vidioc_s_frequency   = vidioc_s_frequency,
  	.vidioc_log_status    = v4l2_ctrl_log_status,
  	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
  	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
  };
  
  static struct video_device usbvision_radio_template = {
  	.fops		= &usbvision_radio_fops,
  	.name		= "usbvision-radio",
  	.release	= video_device_release_empty,
  	.ioctl_ops	= &usbvision_radio_ioctl_ops,
  };
  
  
  static void usbvision_vdev_init(struct usb_usbvision *usbvision,
  				struct video_device *vdev,
  				const struct video_device *vdev_template,
  				const char *name)
  {
  	struct usb_device *usb_dev = usbvision->dev;
  
  	if (!usb_dev) {
  		dev_err(&usbvision->dev->dev,
  			"%s: usbvision->dev is not set\n", __func__);
  		return;
  	}
  
  	*vdev = *vdev_template;
  	vdev->lock = &usbvision->v4l2_lock;
  	vdev->v4l2_dev = &usbvision->v4l2_dev;
  	snprintf(vdev->name, sizeof(vdev->name), "%s", name);
  	video_set_drvdata(vdev, usbvision);
  }
  
  /* unregister video4linux devices */
  static void usbvision_unregister_video(struct usb_usbvision *usbvision)
  {
  	/* Radio Device: */
  	if (video_is_registered(&usbvision->rdev)) {
  		PDEBUG(DBG_PROBE, "unregister %s [v4l2]",
  		       video_device_node_name(&usbvision->rdev));
  		video_unregister_device(&usbvision->rdev);
  	}
  
  	/* Video Device: */
  	if (video_is_registered(&usbvision->vdev)) {
  		PDEBUG(DBG_PROBE, "unregister %s [v4l2]",
  		       video_device_node_name(&usbvision->vdev));
  		video_unregister_device(&usbvision->vdev);
  	}
  }
  
  /* register video4linux devices */
  static int usbvision_register_video(struct usb_usbvision *usbvision)
  {
  	int res = -ENOMEM;
  
  	/* Video Device: */
  	usbvision_vdev_init(usbvision, &usbvision->vdev,
  			      &usbvision_video_template, "USBVision Video");
  	if (!usbvision->have_tuner) {
  		v4l2_disable_ioctl(&usbvision->vdev, VIDIOC_G_FREQUENCY);
  		v4l2_disable_ioctl(&usbvision->vdev, VIDIOC_S_TUNER);
  		v4l2_disable_ioctl(&usbvision->vdev, VIDIOC_G_FREQUENCY);
  		v4l2_disable_ioctl(&usbvision->vdev, VIDIOC_S_TUNER);
  	}
  	usbvision->vdev.device_caps = V4L2_CAP_VIDEO_CAPTURE |
  				      V4L2_CAP_READWRITE | V4L2_CAP_STREAMING;
  	if (usbvision->have_tuner)
  		usbvision->vdev.device_caps |= V4L2_CAP_TUNER;
  
  	if (video_register_device(&usbvision->vdev, VFL_TYPE_GRABBER, video_nr) < 0)
  		goto err_exit;
  	printk(KERN_INFO "USBVision[%d]: registered USBVision Video device %s [v4l2]\n",
  	       usbvision->nr, video_device_node_name(&usbvision->vdev));
  
  	/* Radio Device: */
  	if (usbvision_device_data[usbvision->dev_model].radio) {
  		/* usbvision has radio */
  		usbvision_vdev_init(usbvision, &usbvision->rdev,
  			      &usbvision_radio_template, "USBVision Radio");
  		usbvision->rdev.device_caps = V4L2_CAP_RADIO | V4L2_CAP_TUNER;
  		if (video_register_device(&usbvision->rdev, VFL_TYPE_RADIO, radio_nr) < 0)
  			goto err_exit;
  		printk(KERN_INFO "USBVision[%d]: registered USBVision Radio device %s [v4l2]\n",
  		       usbvision->nr, video_device_node_name(&usbvision->rdev));
  	}
  	/* all done */
  	return 0;
  
   err_exit:
  	dev_err(&usbvision->dev->dev,
  		"USBVision[%d]: video_register_device() failed\n",
  			usbvision->nr);
  	usbvision_unregister_video(usbvision);
  	return res;
  }
  
  /*
   * usbvision_alloc()
   *
   * This code allocates the struct usb_usbvision.
   * It is filled with default values.
   *
   * Returns NULL on error, a pointer to usb_usbvision else.
   *
   */
  static struct usb_usbvision *usbvision_alloc(struct usb_device *dev,
  					     struct usb_interface *intf)
  {
  	struct usb_usbvision *usbvision;
  
  	usbvision = kzalloc(sizeof(*usbvision), GFP_KERNEL);
  	if (!usbvision)
  		return NULL;
  
  	usbvision->dev = dev;
  	if (v4l2_device_register(&intf->dev, &usbvision->v4l2_dev))
  		goto err_free;
  
  	if (v4l2_ctrl_handler_init(&usbvision->hdl, 4))
  		goto err_unreg;
  	usbvision->v4l2_dev.ctrl_handler = &usbvision->hdl;
  	mutex_init(&usbvision->v4l2_lock);
  
  	/* prepare control urb for control messages during interrupts */
  	usbvision->ctrl_urb = usb_alloc_urb(USBVISION_URB_FRAMES, GFP_KERNEL);
  	if (!usbvision->ctrl_urb)
  		goto err_unreg;
  
  	return usbvision;
  
  err_unreg:
  	v4l2_ctrl_handler_free(&usbvision->hdl);
  	v4l2_device_unregister(&usbvision->v4l2_dev);
  err_free:
  	kfree(usbvision);
  	return NULL;
  }
  
  /*
   * usbvision_release()
   *
   * This code does final release of struct usb_usbvision. This happens
   * after the device is disconnected -and- all clients closed their files.
   *
   */
  static void usbvision_release(struct usb_usbvision *usbvision)
  {
  	PDEBUG(DBG_PROBE, "");
  
  	usbvision->initialized = 0;
  
  	usbvision_remove_sysfs(&usbvision->vdev);
  	usbvision_unregister_video(usbvision);
  	kfree(usbvision->alt_max_pkt_size);
  
  	usb_free_urb(usbvision->ctrl_urb);
  
  	v4l2_ctrl_handler_free(&usbvision->hdl);
  	v4l2_device_unregister(&usbvision->v4l2_dev);
  	kfree(usbvision);
  
  	PDEBUG(DBG_PROBE, "success");
  }
  
  
  /*********************** usb interface **********************************/
  
  static void usbvision_configure_video(struct usb_usbvision *usbvision)
  {
  	int model;
  
  	if (!usbvision)
  		return;
  
  	model = usbvision->dev_model;
  	usbvision->palette = usbvision_v4l2_format[2]; /* V4L2_PIX_FMT_RGB24; */
  
  	if (usbvision_device_data[usbvision->dev_model].vin_reg2_override) {
  		usbvision->vin_reg2_preset =
  			usbvision_device_data[usbvision->dev_model].vin_reg2;
  	} else {
  		usbvision->vin_reg2_preset = 0;
  	}
  
  	usbvision->tvnorm_id = usbvision_device_data[model].video_norm;
  	usbvision->video_inputs = usbvision_device_data[model].video_channels;
  	usbvision->ctl_input = 0;
  	usbvision->radio_freq = 87.5 * 16000;
  	usbvision->tv_freq = 400 * 16;
  
  	/* This should be here to make i2c clients to be able to register */
  	/* first switch off audio */
  	if (usbvision_device_data[model].audio_channels > 0)
  		usbvision_audio_off(usbvision);
  	/* and then power up the tuner */
  	usbvision_power_on(usbvision);
  	usbvision_i2c_register(usbvision);
  }
  
  /*
   * usbvision_probe()
   *
   * This procedure queries device descriptor and accepts the interface
   * if it looks like USBVISION video device
   *
   */
  static int usbvision_probe(struct usb_interface *intf,
  			   const struct usb_device_id *devid)
  {
  	struct usb_device *dev = usb_get_dev(interface_to_usbdev(intf));
  	struct usb_interface *uif;
  	__u8 ifnum = intf->altsetting->desc.bInterfaceNumber;
  	const struct usb_host_interface *interface;
  	struct usb_usbvision *usbvision = NULL;
  	const struct usb_endpoint_descriptor *endpoint;
  	int model, i, ret;
  
  	PDEBUG(DBG_PROBE, "VID=%#04x, PID=%#04x, ifnum=%u",
  				le16_to_cpu(dev->descriptor.idVendor),
  				le16_to_cpu(dev->descriptor.idProduct), ifnum);
  
  	model = devid->driver_info;
  	if (model < 0 || model >= usbvision_device_data_size) {
  		PDEBUG(DBG_PROBE, "model out of bounds %d", model);
  		ret = -ENODEV;
  		goto err_usb;
  	}
  	printk(KERN_INFO "%s: %s found\n", __func__,
  				usbvision_device_data[model].model_string);
  
  	if (usbvision_device_data[model].interface >= 0)
  		interface = &dev->actconfig->interface[usbvision_device_data[model].interface]->altsetting[0];
  	else if (ifnum < dev->actconfig->desc.bNumInterfaces)
  		interface = &dev->actconfig->interface[ifnum]->altsetting[0];
  	else {
  		dev_err(&intf->dev, "interface %d is invalid, max is %d\n",
  		    ifnum, dev->actconfig->desc.bNumInterfaces - 1);
  		ret = -ENODEV;
  		goto err_usb;
  	}
  
  	if (interface->desc.bNumEndpoints < 2) {
  		dev_err(&intf->dev, "interface %d has %d endpoints, but must have minimum 2\n",
  			ifnum, interface->desc.bNumEndpoints);
  		ret = -ENODEV;
  		goto err_usb;
  	}
  	endpoint = &interface->endpoint[1].desc;
  
  	if (!usb_endpoint_xfer_isoc(endpoint)) {
  		dev_err(&intf->dev, "%s: interface %d. has non-ISO endpoint!\n",
  		    __func__, ifnum);
  		dev_err(&intf->dev, "%s: Endpoint attributes %d",
  		    __func__, endpoint->bmAttributes);
  		ret = -ENODEV;
  		goto err_usb;
  	}
  	if (usb_endpoint_dir_out(endpoint)) {
  		dev_err(&intf->dev, "%s: interface %d. has ISO OUT endpoint!\n",
  		    __func__, ifnum);
  		ret = -ENODEV;
  		goto err_usb;
  	}
  
  	usbvision = usbvision_alloc(dev, intf);
  	if (!usbvision) {
  		dev_err(&intf->dev, "%s: couldn't allocate USBVision struct\n", __func__);
  		ret = -ENOMEM;
  		goto err_usb;
  	}
  
  	if (dev->descriptor.bNumConfigurations > 1)
  		usbvision->bridge_type = BRIDGE_NT1004;
  	else if (model == DAZZLE_DVC_90_REV_1_SECAM)
  		usbvision->bridge_type = BRIDGE_NT1005;
  	else
  		usbvision->bridge_type = BRIDGE_NT1003;
  	PDEBUG(DBG_PROBE, "bridge_type %d", usbvision->bridge_type);
  
  	/* compute alternate max packet sizes */
  	uif = dev->actconfig->interface[0];
  
  	usbvision->num_alt = uif->num_altsetting;
  	PDEBUG(DBG_PROBE, "Alternate settings: %i", usbvision->num_alt);
  	usbvision->alt_max_pkt_size = kmalloc_array(32, usbvision->num_alt,
  						    GFP_KERNEL);
  	if (!usbvision->alt_max_pkt_size) {
  		ret = -ENOMEM;
  		goto err_pkt;
  	}
  
  	for (i = 0; i < usbvision->num_alt; i++) {
  		u16 tmp;
  
  		if (uif->altsetting[i].desc.bNumEndpoints < 2) {
  			ret = -ENODEV;
  			goto err_pkt;
  		}
  
  		tmp = le16_to_cpu(uif->altsetting[i].endpoint[1].desc.
  				      wMaxPacketSize);
  		usbvision->alt_max_pkt_size[i] =
  			(tmp & 0x07ff) * (((tmp & 0x1800) >> 11) + 1);
  		PDEBUG(DBG_PROBE, "Alternate setting %i, max size= %i", i,
  		       usbvision->alt_max_pkt_size[i]);
  	}
  
  
  	usbvision->nr = usbvision_nr++;
  
  	spin_lock_init(&usbvision->queue_lock);
  	init_waitqueue_head(&usbvision->wait_frame);
  	init_waitqueue_head(&usbvision->wait_stream);
  
  	usbvision->have_tuner = usbvision_device_data[model].tuner;
  	if (usbvision->have_tuner)
  		usbvision->tuner_type = usbvision_device_data[model].tuner_type;
  
  	usbvision->dev_model = model;
  	usbvision->remove_pending = 0;
  	usbvision->iface = ifnum;
  	usbvision->iface_alt = 0;
  	usbvision->video_endp = endpoint->bEndpointAddress;
  	usbvision->isoc_packet_size = 0;
  	usbvision->usb_bandwidth = 0;
  	usbvision->user = 0;
  	usbvision->streaming = stream_off;
  	usbvision_configure_video(usbvision);
  	usbvision_register_video(usbvision);
  
  	usbvision_create_sysfs(&usbvision->vdev);
  
  	PDEBUG(DBG_PROBE, "success");
  	return 0;
  
  err_pkt:
  	usbvision_release(usbvision);
  err_usb:
  	usb_put_dev(dev);
  	return ret;
  }
  
  
  /*
   * usbvision_disconnect()
   *
   * This procedure stops all driver activity, deallocates interface-private
   * structure (pointed by 'ptr') and after that driver should be removable
   * with no ill consequences.
   *
   */
  static void usbvision_disconnect(struct usb_interface *intf)
  {
  	struct usb_usbvision *usbvision = to_usbvision(usb_get_intfdata(intf));
  
  	PDEBUG(DBG_PROBE, "");
  
  	if (!usbvision) {
  		pr_err("%s: usb_get_intfdata() failed\n", __func__);
  		return;
  	}
  
  	mutex_lock(&usbvision->v4l2_lock);
  
  	/* At this time we ask to cancel outstanding URBs */
  	usbvision_stop_isoc(usbvision);
  
  	v4l2_device_disconnect(&usbvision->v4l2_dev);
  	usbvision_i2c_unregister(usbvision);
  	usbvision->remove_pending = 1;	/* Now all ISO data will be ignored */
  
  	usb_put_dev(usbvision->dev);
  	usbvision->dev = NULL;	/* USB device is no more */
  
  	mutex_unlock(&usbvision->v4l2_lock);
  
  	if (usbvision->user) {
  		printk(KERN_INFO "%s: In use, disconnect pending\n",
  		       __func__);
  		wake_up_interruptible(&usbvision->wait_frame);
  		wake_up_interruptible(&usbvision->wait_stream);
  	} else {
  		usbvision_release(usbvision);
  	}
  
  	PDEBUG(DBG_PROBE, "success");
  }
  
  static struct usb_driver usbvision_driver = {
  	.name		= "usbvision",
  	.id_table	= usbvision_table,
  	.probe		= usbvision_probe,
  	.disconnect	= usbvision_disconnect,
  };
  
  /*
   * usbvision_init()
   *
   * This code is run to initialize the driver.
   *
   */
  static int __init usbvision_init(void)
  {
  	int err_code;
  
  	PDEBUG(DBG_PROBE, "");
  
  	PDEBUG(DBG_IO,  "IO      debugging is enabled [video]");
  	PDEBUG(DBG_PROBE, "PROBE   debugging is enabled [video]");
  	PDEBUG(DBG_MMAP, "MMAP    debugging is enabled [video]");
  
  	/* disable planar mode support unless compression enabled */
  	if (isoc_mode != ISOC_MODE_COMPRESS) {
  		/* FIXME : not the right way to set supported flag */
  		usbvision_v4l2_format[6].supported = 0; /* V4L2_PIX_FMT_YVU420 */
  		usbvision_v4l2_format[7].supported = 0; /* V4L2_PIX_FMT_YUV422P */
  	}
  
  	err_code = usb_register(&usbvision_driver);
  
  	if (err_code == 0) {
  		printk(KERN_INFO DRIVER_DESC " : " USBVISION_VERSION_STRING "\n");
  		PDEBUG(DBG_PROBE, "success");
  	}
  	return err_code;
  }
  
  static void __exit usbvision_exit(void)
  {
  	PDEBUG(DBG_PROBE, "");
  
  	usb_deregister(&usbvision_driver);
  	PDEBUG(DBG_PROBE, "success");
  }
  
  module_init(usbvision_init);
  module_exit(usbvision_exit);
  