V4L/DVB (3599a): Move drivers/usb/media to drivers/media/video

Because of historic reasons, there are two separate directories with
V4L stuff. Most drivers are located at driver/media/video. However, some
code for USB Webcams were inserted under drivers/usb/media.

This makes difficult for module authors to know were things should be.
Also, makes Kconfig menu confusing for normal users.

This patch moves all V4L content under drivers/usb/media to
drivers/media/video, and fixes Kconfig/Makefile entries.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 2205 insertions, 0 deletions

diff --git a/drivers/media/video/pwc/pwc-if.c b/drivers/media/video/pwc/pwc-if.c
new file mode 100644
index 00000000000..90eb2604281
--- /dev/null
+++ b/drivers/media/video/pwc/pwc-if.c
@@ -0,0 +1,2205 @@
+/* Linux driver for Philips webcam
+   USB and Video4Linux interface part.
+   (C) 1999-2004 Nemosoft Unv.
+   (C) 2004      Luc Saillard (luc@saillard.org)
+
+   NOTE: this version of pwc is an unofficial (modified) release of pwc & pcwx
+   driver and thus may have bugs that are not present in the original version.
+   Please send bug reports and support requests to <luc@saillard.org>.
+   The decompression routines have been implemented by reverse-engineering the
+   Nemosoft binary pwcx module. Caveat emptor.
+
+   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
+
+*/
+
+/*  
+   This code forms the interface between the USB layers and the Philips
+   specific stuff. Some adanved stuff of the driver falls under an
+   NDA, signed between me and Philips B.V., Eindhoven, the Netherlands, and
+   is thus not distributed in source form. The binary pwcx.o module 
+   contains the code that falls under the NDA.
+   
+   In case you're wondering: 'pwc' stands for "Philips WebCam", but 
+   I really didn't want to type 'philips_web_cam' every time (I'm lazy as
+   any Linux kernel hacker, but I don't like uncomprehensible abbreviations
+   without explanation).
+   
+   Oh yes, convention: to disctinguish between all the various pointers to
+   device-structures, I use these names for the pointer variables:
+   udev: struct usb_device *
+   vdev: struct video_device *
+   pdev: struct pwc_devive *
+*/
+
+/* Contributors:
+   - Alvarado: adding whitebalance code
+   - Alistar Moire: QuickCam 3000 Pro device/product ID
+   - Tony Hoyle: Creative Labs Webcam 5 device/product ID
+   - Mark Burazin: solving hang in VIDIOCSYNC when camera gets unplugged
+   - Jk Fang: Sotec Afina Eye ID
+   - Xavier Roche: QuickCam Pro 4000 ID
+   - Jens Knudsen: QuickCam Zoom ID
+   - J. Debert: QuickCam for Notebooks ID
+*/
+
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/poll.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <asm/io.h>
+
+#include "pwc.h"
+#include "pwc-ioctl.h"
+#include "pwc-kiara.h"
+#include "pwc-timon.h"
+#include "pwc-uncompress.h"
+
+/* Function prototypes and driver templates */
+
+/* hotplug device table support */
+static struct usb_device_id pwc_device_table [] = {
+	{ USB_DEVICE(0x0471, 0x0302) }, /* Philips models */
+	{ USB_DEVICE(0x0471, 0x0303) },
+	{ USB_DEVICE(0x0471, 0x0304) },
+	{ USB_DEVICE(0x0471, 0x0307) },
+	{ USB_DEVICE(0x0471, 0x0308) },
+	{ USB_DEVICE(0x0471, 0x030C) },
+	{ USB_DEVICE(0x0471, 0x0310) },
+	{ USB_DEVICE(0x0471, 0x0311) },
+	{ USB_DEVICE(0x0471, 0x0312) },
+	{ USB_DEVICE(0x0471, 0x0313) }, /* the 'new' 720K */
+	{ USB_DEVICE(0x069A, 0x0001) }, /* Askey */
+	{ USB_DEVICE(0x046D, 0x08B0) }, /* Logitech QuickCam Pro 3000 */
+	{ USB_DEVICE(0x046D, 0x08B1) }, /* Logitech QuickCam Notebook Pro */
+	{ USB_DEVICE(0x046D, 0x08B2) }, /* Logitech QuickCam Pro 4000 */
+	{ USB_DEVICE(0x046D, 0x08B3) }, /* Logitech QuickCam Zoom (old model) */
+	{ USB_DEVICE(0x046D, 0x08B4) }, /* Logitech QuickCam Zoom (new model) */
+	{ USB_DEVICE(0x046D, 0x08B5) }, /* Logitech QuickCam Orbit/Sphere */
+	{ USB_DEVICE(0x046D, 0x08B6) }, /* Logitech (reserved) */
+	{ USB_DEVICE(0x046D, 0x08B7) }, /* Logitech (reserved) */
+	{ USB_DEVICE(0x046D, 0x08B8) }, /* Logitech (reserved) */
+	{ USB_DEVICE(0x055D, 0x9000) }, /* Samsung */
+	{ USB_DEVICE(0x055D, 0x9001) },
+	{ USB_DEVICE(0x041E, 0x400C) }, /* Creative Webcam 5 */
+	{ USB_DEVICE(0x041E, 0x4011) }, /* Creative Webcam Pro Ex */
+	{ USB_DEVICE(0x04CC, 0x8116) }, /* Afina Eye */
+	{ USB_DEVICE(0x06BE, 0x8116) }, /* new Afina Eye */
+	{ USB_DEVICE(0x0d81, 0x1910) }, /* Visionite */
+	{ USB_DEVICE(0x0d81, 0x1900) },
+	{ }
+};
+MODULE_DEVICE_TABLE(usb, pwc_device_table);
+
+static int usb_pwc_probe(struct usb_interface *intf, const struct usb_device_id *id);
+static void usb_pwc_disconnect(struct usb_interface *intf);
+
+static struct usb_driver pwc_driver = {
+	.name =			"Philips webcam",	/* name */
+	.id_table =		pwc_device_table,
+	.probe =		usb_pwc_probe,		/* probe() */
+	.disconnect =		usb_pwc_disconnect,	/* disconnect() */
+};
+
+#define MAX_DEV_HINTS	20
+#define MAX_ISOC_ERRORS	20
+
+static int default_size = PSZ_QCIF;
+static int default_fps = 10;
+static int default_fbufs = 3;   /* Default number of frame buffers */
+static int default_mbufs = 2;	/* Default number of mmap() buffers */
+       int pwc_trace = TRACE_MODULE | TRACE_FLOW | TRACE_PWCX;
+static int power_save = 0;
+static int led_on = 100, led_off = 0; /* defaults to LED that is on while in use */
+static int pwc_preferred_compression = 2; /* 0..3 = uncompressed..high */
+static struct {
+	int type;
+	char serial_number[30];
+	int device_node;
+	struct pwc_device *pdev;
+} device_hint[MAX_DEV_HINTS];
+
+/***/
+
+static int pwc_video_open(struct inode *inode, struct file *file);
+static int pwc_video_close(struct inode *inode, struct file *file);
+static ssize_t pwc_video_read(struct file *file, char __user * buf,
+			  size_t count, loff_t *ppos);
+static unsigned int pwc_video_poll(struct file *file, poll_table *wait);
+static int  pwc_video_ioctl(struct inode *inode, struct file *file,
+			    unsigned int ioctlnr, unsigned long arg);
+static int  pwc_video_mmap(struct file *file, struct vm_area_struct *vma);
+
+static struct file_operations pwc_fops = {
+	.owner =	THIS_MODULE,
+	.open =		pwc_video_open,
+	.release =     	pwc_video_close,
+	.read =		pwc_video_read,
+	.poll =		pwc_video_poll,
+	.mmap =		pwc_video_mmap,
+	.ioctl =        pwc_video_ioctl,
+	.compat_ioctl = v4l_compat_ioctl32,
+	.llseek =       no_llseek,
+};
+static struct video_device pwc_template = {
+	.owner =	THIS_MODULE,
+	.name =		"Philips Webcam",	/* Filled in later */
+	.type =		VID_TYPE_CAPTURE,
+	.hardware =	VID_HARDWARE_PWC,
+	.release =	video_device_release,
+	.fops =         &pwc_fops,
+	.minor =        -1,
+};
+
+/***************************************************************************/
+
+/* Okay, this is some magic that I worked out and the reasoning behind it...
+
+   The biggest problem with any USB device is of course: "what to do 
+   when the user unplugs the device while it is in use by an application?"
+   We have several options:
+   1) Curse them with the 7 plagues when they do (requires divine intervention)
+   2) Tell them not to (won't work: they'll do it anyway)
+   3) Oops the kernel (this will have a negative effect on a user's uptime)
+   4) Do something sensible.
+   
+   Of course, we go for option 4.
+
+   It happens that this device will be linked to two times, once from
+   usb_device and once from the video_device in their respective 'private'
+   pointers. This is done when the device is probed() and all initialization
+   succeeded. The pwc_device struct links back to both structures.
+
+   When a device is unplugged while in use it will be removed from the 
+   list of known USB devices; I also de-register it as a V4L device, but 
+   unfortunately I can't free the memory since the struct is still in use
+   by the file descriptor. This free-ing is then deferend until the first
+   opportunity. Crude, but it works.
+   
+   A small 'advantage' is that if a user unplugs the cam and plugs it back
+   in, it should get assigned the same video device minor, but unfortunately
+   it's non-trivial to re-link the cam back to the video device... (that 
+   would surely be magic! :))
+*/
+
+/***************************************************************************/
+/* Private functions */
+
+/* Here we want the physical address of the memory.
+ * This is used when initializing the contents of the area.
+ */
+static inline unsigned long kvirt_to_pa(unsigned long adr) 
+{
+        unsigned long kva, ret;
+
+	kva = (unsigned long) page_address(vmalloc_to_page((void *)adr));
+	kva |= adr & (PAGE_SIZE-1); /* restore the offset */
+	ret = __pa(kva);
+        return ret;
+}
+
+static void * rvmalloc(unsigned long size)
+{
+	void * mem;
+	unsigned long adr;
+
+	size=PAGE_ALIGN(size);
+        mem=vmalloc_32(size);
+	if (mem) 
+	{
+		memset(mem, 0, size); /* Clear the ram out, no junk to the user */
+	        adr=(unsigned long) mem;
+		while (size > 0) 
+                {
+			SetPageReserved(vmalloc_to_page((void *)adr));
+			adr+=PAGE_SIZE;
+			size-=PAGE_SIZE;
+		}
+	}
+	return mem;
+}
+
+static void rvfree(void * mem, unsigned long size)
+{
+        unsigned long adr;
+
+	if (mem) 
+	{
+	        adr=(unsigned long) mem;
+		while ((long) size > 0) 
+                {
+			ClearPageReserved(vmalloc_to_page((void *)adr));
+			adr+=PAGE_SIZE;
+			size-=PAGE_SIZE;
+		}
+		vfree(mem);
+	}
+}
+
+
+
+
+static int pwc_allocate_buffers(struct pwc_device *pdev)
+{
+	int i;
+	void *kbuf;
+
+	Trace(TRACE_MEMORY, ">> pwc_allocate_buffers(pdev = 0x%p)\n", pdev);
+
+	if (pdev == NULL)
+		return -ENXIO;
+		
+#ifdef PWC_MAGIC
+	if (pdev->magic != PWC_MAGIC) {
+		Err("allocate_buffers(): magic failed.\n");
+		return -ENXIO;
+	}
+#endif	
+	/* Allocate Isochronous pipe buffers */
+	for (i = 0; i < MAX_ISO_BUFS; i++) {
+		if (pdev->sbuf[i].data == NULL) {
+			kbuf = kmalloc(ISO_BUFFER_SIZE, GFP_KERNEL);
+			if (kbuf == NULL) {
+				Err("Failed to allocate iso buffer %d.\n", i);
+				return -ENOMEM;
+			}
+			Trace(TRACE_MEMORY, "Allocated iso buffer at %p.\n", kbuf);
+			pdev->sbuf[i].data = kbuf;
+			memset(kbuf, 0, ISO_BUFFER_SIZE);
+		}
+	}
+
+	/* Allocate frame buffer structure */
+	if (pdev->fbuf == NULL) {
+		kbuf = kmalloc(default_fbufs * sizeof(struct pwc_frame_buf), GFP_KERNEL);
+		if (kbuf == NULL) {
+			Err("Failed to allocate frame buffer structure.\n");
+			return -ENOMEM;
+		}
+		Trace(TRACE_MEMORY, "Allocated frame buffer structure at %p.\n", kbuf);
+		pdev->fbuf = kbuf;
+		memset(kbuf, 0, default_fbufs * sizeof(struct pwc_frame_buf));
+	}
+	/* create frame buffers, and make circular ring */
+	for (i = 0; i < default_fbufs; i++) {
+		if (pdev->fbuf[i].data == NULL) {
+			kbuf = vmalloc(PWC_FRAME_SIZE); /* need vmalloc since frame buffer > 128K */
+			if (kbuf == NULL) {
+				Err("Failed to allocate frame buffer %d.\n", i);
+				return -ENOMEM;
+			}
+			Trace(TRACE_MEMORY, "Allocated frame buffer %d at %p.\n", i, kbuf);
+			pdev->fbuf[i].data = kbuf;
+			memset(kbuf, 128, PWC_FRAME_SIZE);
+		}
+	}
+	
+	/* Allocate decompressor table space */
+	kbuf = NULL;
+	switch (pdev->type)
+	 {
+	  case 675:
+	  case 680:
+	  case 690:
+	  case 720:
+	  case 730:
+	  case 740:
+	  case 750:
+#if 0	  
+	    Trace(TRACE_MEMORY,"private_data(%zu)\n",sizeof(struct pwc_dec23_private));
+	    kbuf = kmalloc(sizeof(struct pwc_dec23_private), GFP_KERNEL);	/* Timon & Kiara */
+	    break;
+	  case 645:
+	  case 646:
+	    /* TODO & FIXME */
+	    kbuf = kmalloc(sizeof(struct pwc_dec23_private), GFP_KERNEL);
+	    break;
+#endif	 
+	;
+	 }
+	pdev->decompress_data = kbuf;
+	
+	/* Allocate image buffer; double buffer for mmap() */
+	kbuf = rvmalloc(default_mbufs * pdev->len_per_image);
+	if (kbuf == NULL) {
+		Err("Failed to allocate image buffer(s). needed (%d)\n",default_mbufs * pdev->len_per_image);
+		return -ENOMEM;
+	}
+	Trace(TRACE_MEMORY, "Allocated image buffer at %p.\n", kbuf);
+	pdev->image_data = kbuf;
+	for (i = 0; i < default_mbufs; i++)
+		pdev->image_ptr[i] = kbuf + i * pdev->len_per_image;
+	for (; i < MAX_IMAGES; i++)
+		pdev->image_ptr[i] = NULL;
+
+	kbuf = NULL;
+	  
+	Trace(TRACE_MEMORY, "<< pwc_allocate_buffers()\n");
+	return 0;
+}
+
+static void pwc_free_buffers(struct pwc_device *pdev)
+{
+	int i;
+
+	Trace(TRACE_MEMORY, "Entering free_buffers(%p).\n", pdev);
+
+	if (pdev == NULL)
+		return;
+#ifdef PWC_MAGIC
+	if (pdev->magic != PWC_MAGIC) {
+		Err("free_buffers(): magic failed.\n");
+		return;
+	}
+#endif	
+
+	/* Release Iso-pipe buffers */
+	for (i = 0; i < MAX_ISO_BUFS; i++)
+		if (pdev->sbuf[i].data != NULL) {
+			Trace(TRACE_MEMORY, "Freeing ISO buffer at %p.\n", pdev->sbuf[i].data);
+			kfree(pdev->sbuf[i].data);
+			pdev->sbuf[i].data = NULL;
+		}
+
+	/* The same for frame buffers */
+	if (pdev->fbuf != NULL) {
+		for (i = 0; i < default_fbufs; i++) {
+			if (pdev->fbuf[i].data != NULL) {
+				Trace(TRACE_MEMORY, "Freeing frame buffer %d at %p.\n", i, pdev->fbuf[i].data);
+				vfree(pdev->fbuf[i].data);
+				pdev->fbuf[i].data = NULL;
+			}
+		}
+		kfree(pdev->fbuf);
+		pdev->fbuf = NULL;
+	}
+
+	/* Intermediate decompression buffer & tables */
+	if (pdev->decompress_data != NULL) {
+		Trace(TRACE_MEMORY, "Freeing decompression buffer at %p.\n", pdev->decompress_data);
+		kfree(pdev->decompress_data);
+		pdev->decompress_data = NULL;
+	}
+	pdev->decompressor = NULL;
+
+	/* Release image buffers */
+	if (pdev->image_data != NULL) {
+		Trace(TRACE_MEMORY, "Freeing image buffer at %p.\n", pdev->image_data);
+		rvfree(pdev->image_data, default_mbufs * pdev->len_per_image);
+	}
+	pdev->image_data = NULL;
+	
+	Trace(TRACE_MEMORY, "Leaving free_buffers().\n");
+}
+
+/* The frame & image buffer mess. 
+
+   Yes, this is a mess. Well, it used to be simple, but alas...  In this
+   module, 3 buffers schemes are used to get the data from the USB bus to
+   the user program. The first scheme involves the ISO buffers (called thus
+   since they transport ISO data from the USB controller), and not really
+   interesting. Suffices to say the data from this buffer is quickly 
+   gathered in an interrupt handler (pwc_isoc_handler) and placed into the
+   frame buffer.
+
+   The frame buffer is the second scheme, and is the central element here.
+   It collects the data from a single frame from the camera (hence, the
+   name). Frames are delimited by the USB camera with a short USB packet,
+   so that's easy to detect. The frame buffers form a list that is filled
+   by the camera+USB controller and drained by the user process through
+   either read() or mmap().
+
+   The image buffer is the third scheme, in which frames are decompressed
+   and converted into planar format. For mmap() there is more than
+   one image buffer available.
+
+   The frame buffers provide the image buffering. In case the user process
+   is a bit slow, this introduces lag and some undesired side-effects.
+   The problem arises when the frame buffer is full. I used to drop the last
+   frame, which makes the data in the queue stale very quickly. But dropping
+   the frame at the head of the queue proved to be a litte bit more difficult.
+   I tried a circular linked scheme, but this introduced more problems than
+   it solved.
+
+   Because filling and draining are completely asynchronous processes, this
+   requires some fiddling with pointers and mutexes.
+
+   Eventually, I came up with a system with 2 lists: an 'empty' frame list
+   and a 'full' frame list:
+     * Initially, all frame buffers but one are on the 'empty' list; the one
+       remaining buffer is our initial fill frame.
+     * If a frame is needed for filling, we try to take it from the 'empty' 
+       list, unless that list is empty, in which case we take the buffer at 
+       the head of the 'full' list.
+     * When our fill buffer has been filled, it is appended to the 'full'
+       list.
+     * If a frame is needed by read() or mmap(), it is taken from the head of
+       the 'full' list, handled, and then appended to the 'empty' list. If no
+       buffer is present on the 'full' list, we wait.
+   The advantage is that the buffer that is currently being decompressed/
+   converted, is on neither list, and thus not in our way (any other scheme
+   I tried had the problem of old data lingering in the queue).
+
+   Whatever strategy you choose, it always remains a tradeoff: with more
+   frame buffers the chances of a missed frame are reduced. On the other
+   hand, on slower machines it introduces lag because the queue will
+   always be full.
+ */
+
+/**
+  \brief Find next frame buffer to fill. Take from empty or full list, whichever comes first.
+ */
+static inline int pwc_next_fill_frame(struct pwc_device *pdev)
+{
+	int ret;
+	unsigned long flags;
+
+	ret = 0;
+	spin_lock_irqsave(&pdev->ptrlock, flags);
+	if (pdev->fill_frame != NULL) {
+		/* append to 'full' list */
+		if (pdev->full_frames == NULL) {
+			pdev->full_frames = pdev->fill_frame;
+			pdev->full_frames_tail = pdev->full_frames;
+		}
+		else {
+			pdev->full_frames_tail->next = pdev->fill_frame;
+			pdev->full_frames_tail = pdev->fill_frame;
+		}
+	}
+	if (pdev->empty_frames != NULL) {
+		/* We have empty frames available. That's easy */
+		pdev->fill_frame = pdev->empty_frames;
+		pdev->empty_frames = pdev->empty_frames->next;
+	}
+	else {
+		/* Hmm. Take it from the full list */
+#if PWC_DEBUG
+		/* sanity check */
+		if (pdev->full_frames == NULL) {
+			Err("Neither empty or full frames available!\n");
+			spin_unlock_irqrestore(&pdev->ptrlock, flags);
+			return -EINVAL;
+		}
+#endif
+		pdev->fill_frame = pdev->full_frames;
+		pdev->full_frames = pdev->full_frames->next;
+		ret = 1;
+	}
+	pdev->fill_frame->next = NULL;
+#if PWC_DEBUG
+	Trace(TRACE_SEQUENCE, "Assigning sequence number %d.\n", pdev->sequence);
+	pdev->fill_frame->sequence = pdev->sequence++;
+#endif
+	spin_unlock_irqrestore(&pdev->ptrlock, flags);
+	return ret;
+}
+
+
+/**
+  \brief Reset all buffers, pointers and lists, except for the image_used[] buffer.
+
+  If the image_used[] buffer is cleared too, mmap()/VIDIOCSYNC will run into trouble.
+ */
+static void pwc_reset_buffers(struct pwc_device *pdev)
+{
+	int i;
+	unsigned long flags;
+
+	spin_lock_irqsave(&pdev->ptrlock, flags);
+	pdev->full_frames = NULL;
+	pdev->full_frames_tail = NULL;
+	for (i = 0; i < default_fbufs; i++) {
+		pdev->fbuf[i].filled = 0;
+		if (i > 0)
+			pdev->fbuf[i].next = &pdev->fbuf[i - 1];
+		else
+			pdev->fbuf->next = NULL;
+	}
+	pdev->empty_frames = &pdev->fbuf[default_fbufs - 1];
+	pdev->empty_frames_tail = pdev->fbuf;
+	pdev->read_frame = NULL;
+	pdev->fill_frame = pdev->empty_frames;
+	pdev->empty_frames = pdev->empty_frames->next;
+
+	pdev->image_read_pos = 0;
+	pdev->fill_image = 0;
+	spin_unlock_irqrestore(&pdev->ptrlock, flags);
+}
+
+
+/**
+  \brief Do all the handling for getting one frame: get pointer, decompress, advance pointers.
+ */
+static int pwc_handle_frame(struct pwc_device *pdev)
+{
+	int ret = 0;
+	unsigned long flags;
+
+	spin_lock_irqsave(&pdev->ptrlock, flags);
+	/* First grab our read_frame; this is removed from all lists, so
+	   we can release the lock after this without problems */
+	if (pdev->read_frame != NULL) {
+		/* This can't theoretically happen */
+		Err("Huh? Read frame still in use?\n");
+	}
+	else {
+		if (pdev->full_frames == NULL) {
+			Err("Woops. No frames ready.\n");
+		}
+		else {
+			pdev->read_frame = pdev->full_frames;
+			pdev->full_frames = pdev->full_frames->next;
+			pdev->read_frame->next = NULL;
+		}
+
+		if (pdev->read_frame != NULL) {
+#if PWC_DEBUG
+			Trace(TRACE_SEQUENCE, "Decompressing frame %d\n", pdev->read_frame->sequence);
+#endif
+			/* Decompression is a lenghty process, so it's outside of the lock.
+			   This gives the isoc_handler the opportunity to fill more frames
+			   in the mean time.
+			*/
+			spin_unlock_irqrestore(&pdev->ptrlock, flags);
+			ret = pwc_decompress(pdev);
+			spin_lock_irqsave(&pdev->ptrlock, flags);
+
+			/* We're done with read_buffer, tack it to the end of the empty buffer list */
+			if (pdev->empty_frames == NULL) {
+				pdev->empty_frames = pdev->read_frame;
+				pdev->empty_frames_tail = pdev->empty_frames;
+			}
+			else {
+				pdev->empty_frames_tail->next = pdev->read_frame;
+				pdev->empty_frames_tail = pdev->read_frame;
+			}
+			pdev->read_frame = NULL;
+		}
+	}
+	spin_unlock_irqrestore(&pdev->ptrlock, flags);
+	return ret;
+}
+
+/**
+  \brief Advance pointers of image buffer (after each user request)
+*/
+static inline void pwc_next_image(struct pwc_device *pdev)
+{
+	pdev->image_used[pdev->fill_image] = 0;
+	pdev->fill_image = (pdev->fill_image + 1) % default_mbufs;
+}
+
+
+/* This gets called for the Isochronous pipe (video). This is done in
+ * interrupt time, so it has to be fast, not crash, and not stall. Neat.
+ */
+static void pwc_isoc_handler(struct urb *urb, struct pt_regs *regs)
+{
+	struct pwc_device *pdev;
+	int i, fst, flen;
+	int awake;
+	struct pwc_frame_buf *fbuf;
+	unsigned char *fillptr = NULL, *iso_buf = NULL;
+
+	awake = 0;
+	pdev = (struct pwc_device *)urb->context;
+	if (pdev == NULL) {
+		Err("isoc_handler() called with NULL device?!\n");
+		return;
+	}
+#ifdef PWC_MAGIC
+	if (pdev->magic != PWC_MAGIC) {
+		Err("isoc_handler() called with bad magic!\n");
+		return;
+	}
+#endif
+	if (urb->status == -ENOENT || urb->status == -ECONNRESET) {
+		Trace(TRACE_OPEN, "pwc_isoc_handler(): URB (%p) unlinked %ssynchronuously.\n", urb, urb->status == -ENOENT ? "" : "a");
+		return;
+	}
+	if (urb->status != -EINPROGRESS && urb->status != 0) {
+		const char *errmsg;
+
+		errmsg = "Unknown";
+		switch(urb->status) {
+			case -ENOSR:		errmsg = "Buffer error (overrun)"; break;
+			case -EPIPE:		errmsg = "Stalled (device not responding)"; break;
+			case -EOVERFLOW:	errmsg = "Babble (bad cable?)"; break;
+			case -EPROTO:		errmsg = "Bit-stuff error (bad cable?)"; break;
+			case -EILSEQ:		errmsg = "CRC/Timeout (could be anything)"; break;
+			case -ETIMEDOUT:	errmsg = "NAK (device does not respond)"; break;
+		}
+		Trace(TRACE_FLOW, "pwc_isoc_handler() called with status %d [%s].\n", urb->status, errmsg);
+		/* Give up after a number of contiguous errors on the USB bus. 
+		   Appearantly something is wrong so we simulate an unplug event.
+		 */
+		if (++pdev->visoc_errors > MAX_ISOC_ERRORS)
+		{
+			Info("Too many ISOC errors, bailing out.\n");
+			pdev->error_status = EIO;
+			awake = 1;
+			wake_up_interruptible(&pdev->frameq);
+		}
+		goto handler_end; // ugly, but practical
+	}
+
+	fbuf = pdev->fill_frame;
+	if (fbuf == NULL) {
+		Err("pwc_isoc_handler without valid fill frame.\n");
+		awake = 1;
+		goto handler_end;
+	}
+	else {
+		fillptr = fbuf->data + fbuf->filled;
+	}
+
+	/* Reset ISOC error counter. We did get here, after all. */
+	pdev->visoc_errors = 0;
+
+	/* vsync: 0 = don't copy data
+	          1 = sync-hunt
+	          2 = synched
+	 */
+	/* Compact data */
+	for (i = 0; i < urb->number_of_packets; i++) {
+		fst  = urb->iso_frame_desc[i].status;
+		flen = urb->iso_frame_desc[i].actual_length;
+		iso_buf = urb->transfer_buffer + urb->iso_frame_desc[i].offset;
+		if (fst == 0) {
+			if (flen > 0) { /* if valid data... */
+				if (pdev->vsync > 0) { /* ...and we are not sync-hunting... */
+					pdev->vsync = 2;
+
+					/* ...copy data to frame buffer, if possible */
+					if (flen + fbuf->filled > pdev->frame_total_size) {
+						Trace(TRACE_FLOW, "Frame buffer overflow (flen = %d, frame_total_size = %d).\n", flen, pdev->frame_total_size);
+						pdev->vsync = 0; /* Hmm, let's wait for an EOF (end-of-frame) */
+						pdev->vframes_error++;
+					}
+					else {
+						memmove(fillptr, iso_buf, flen);
+						fillptr += flen;
+					}
+				}
+				fbuf->filled += flen;
+			} /* ..flen > 0 */
+
+			if (flen < pdev->vlast_packet_size) {
+				/* Shorter packet... We probably have the end of an image-frame; 
+				   wake up read() process and let select()/poll() do something.
+				   Decompression is done in user time over there.
+				 */
+				if (pdev->vsync == 2) {
+					/* The ToUCam Fun CMOS sensor causes the firmware to send 2 or 3 bogus 
+					   frames on the USB wire after an exposure change. This conditition is 
+					   however detected  in the cam and a bit is set in the header.
+					 */
+					if (pdev->type == 730) {
+						unsigned char *ptr = (unsigned char *)fbuf->data;
+						
+						if (ptr[1] == 1 && ptr[0] & 0x10) {
+#if PWC_DEBUG
+							Debug("Hyundai CMOS sensor bug. Dropping frame %d.\n", fbuf->sequence);
+#endif
+							pdev->drop_frames += 2;
+							pdev->vframes_error++;
+						}
+						if ((ptr[0] ^ pdev->vmirror) & 0x01) {
+							if (ptr[0] & 0x01)
+								Info("Snapshot button pressed.\n");
+							else
+								Info("Snapshot button released.\n");
+						}
+						if ((ptr[0] ^ pdev->vmirror) & 0x02) {
+							if (ptr[0] & 0x02)
+								Info("Image is mirrored.\n");
+							else
+								Info("Image is normal.\n");
+						}
+						pdev->vmirror = ptr[0] & 0x03;
+						/* Sometimes the trailer of the 730 is still sent as a 4 byte packet 
+						   after a short frame; this condition is filtered out specifically. A 4 byte
+						   frame doesn't make sense anyway.
+						   So we get either this sequence: 
+						   	drop_bit set -> 4 byte frame -> short frame -> good frame
+						   Or this one:
+						   	drop_bit set -> short frame -> good frame
+						   So we drop either 3 or 2 frames in all!
+						 */
+						if (fbuf->filled == 4)
+							pdev->drop_frames++;
+					}
+
+					/* In case we were instructed to drop the frame, do so silently.
+					   The buffer pointers are not updated either (but the counters are reset below).
+					 */
+					if (pdev->drop_frames > 0)
+						pdev->drop_frames--;
+					else {
+						/* Check for underflow first */
+						if (fbuf->filled < pdev->frame_total_size) {
+							Trace(TRACE_FLOW, "Frame buffer underflow (%d bytes); discarded.\n", fbuf->filled);
+							pdev->vframes_error++;
+						}
+						else {
+							/* Send only once per EOF */
+							awake = 1; /* delay wake_ups */
+
+							/* Find our next frame to fill. This will always succeed, since we
+							 * nick a frame from either empty or full list, but if we had to
+							 * take it from the full list, it means a frame got dropped.
+							 */
+							if (pwc_next_fill_frame(pdev)) {
+								pdev->vframes_dumped++;
+								if ((pdev->vframe_count > FRAME_LOWMARK) && (pwc_trace & TRACE_FLOW)) {
+									if (pdev->vframes_dumped < 20)
+										Trace(TRACE_FLOW, "Dumping frame %d.\n", pdev->vframe_count);
+									if (pdev->vframes_dumped == 20)
+										Trace(TRACE_FLOW, "Dumping frame %d (last message).\n", pdev->vframe_count);
+								}
+							}
+							fbuf = pdev->fill_frame;
+						}
+					} /* !drop_frames */
+					pdev->vframe_count++;
+				}
+				fbuf->filled = 0;
+				fillptr = fbuf->data;
+				pdev->vsync = 1;
+			} /* .. flen < last_packet_size */
+			pdev->vlast_packet_size = flen;
+		} /* ..status == 0 */
+#if PWC_DEBUG
+		/* This is normally not interesting to the user, unless you are really debugging something */
+		else {
+			static int iso_error = 0;
+			iso_error++;
+			if (iso_error < 20)
+				Trace(TRACE_FLOW, "Iso frame %d of USB has error %d\n", i, fst);
+		}
+#endif
+	}
+
+handler_end:
+	if (awake)
+		wake_up_interruptible(&pdev->frameq);
+
+	urb->dev = pdev->udev;
+	i = usb_submit_urb(urb, GFP_ATOMIC);
+	if (i != 0)
+		Err("Error (%d) re-submitting urb in pwc_isoc_handler.\n", i);
+}
+
+
+static int pwc_isoc_init(struct pwc_device *pdev)
+{
+	struct usb_device *udev;
+	struct urb *urb;
+	int i, j, ret;
+
+	struct usb_interface *intf;
+	struct usb_host_interface *idesc = NULL;
+
+	if (pdev == NULL)
+		return -EFAULT;
+	if (pdev->iso_init)
+		return 0;
+	pdev->vsync = 0;
+	udev = pdev->udev;
+
+	/* Get the current alternate interface, adjust packet size */
+	if (!udev->actconfig)
+		return -EFAULT;
+
+	intf = usb_ifnum_to_if(udev, 0);
+	if (intf)
+		idesc = usb_altnum_to_altsetting(intf, pdev->valternate);
+		
+	if (!idesc)
+		return -EFAULT;
+
+	/* Search video endpoint */
+	pdev->vmax_packet_size = -1;
+	for (i = 0; i < idesc->desc.bNumEndpoints; i++)
+		if ((idesc->endpoint[i].desc.bEndpointAddress & 0xF) == pdev->vendpoint) {
+			pdev->vmax_packet_size = le16_to_cpu(idesc->endpoint[i].desc.wMaxPacketSize);
+			break;
+		}
+	
+	if (pdev->vmax_packet_size < 0 || pdev->vmax_packet_size > ISO_MAX_FRAME_SIZE) {
+		Err("Failed to find packet size for video endpoint in current alternate setting.\n");
+		return -ENFILE; /* Odd error, that should be noticeable */
+	}
+
+	/* Set alternate interface */
+	ret = 0;
+	Trace(TRACE_OPEN, "Setting alternate interface %d\n", pdev->valternate);
+	ret = usb_set_interface(pdev->udev, 0, pdev->valternate);
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < MAX_ISO_BUFS; i++) {
+		urb = usb_alloc_urb(ISO_FRAMES_PER_DESC, GFP_KERNEL);
+		if (urb == NULL) {
+			Err("Failed to allocate urb %d\n", i);
+			ret = -ENOMEM;
+			break;
+		}
+		pdev->sbuf[i].urb = urb;
+		Trace(TRACE_MEMORY, "Allocated URB at 0x%p\n", urb);
+	}
+	if (ret) {
+		/* De-allocate in reverse order */
+		while (i >= 0) {
+			if (pdev->sbuf[i].urb != NULL)
+				usb_free_urb(pdev->sbuf[i].urb);
+			pdev->sbuf[i].urb = NULL;
+			i--;
+		}
+		return ret;
+	}
+
+	/* init URB structure */	
+	for (i = 0; i < MAX_ISO_BUFS; i++) {
+		urb = pdev->sbuf[i].urb;
+
+		urb->interval = 1; // devik
+		urb->dev = udev;
+	        urb->pipe = usb_rcvisocpipe(udev, pdev->vendpoint);
+		urb->transfer_flags = URB_ISO_ASAP;
+	        urb->transfer_buffer = pdev->sbuf[i].data;
+	        urb->transfer_buffer_length = ISO_BUFFER_SIZE;
+	        urb->complete = pwc_isoc_handler;
+	        urb->context = pdev;
+		urb->start_frame = 0;
+		urb->number_of_packets = ISO_FRAMES_PER_DESC;
+		for (j = 0; j < ISO_FRAMES_PER_DESC; j++) {
+			urb->iso_frame_desc[j].offset = j * ISO_MAX_FRAME_SIZE;
+			urb->iso_frame_desc[j].length = pdev->vmax_packet_size;
+		}
+	}
+
+	/* link */
+	for (i = 0; i < MAX_ISO_BUFS; i++) {
+		ret = usb_submit_urb(pdev->sbuf[i].urb, GFP_KERNEL);
+		if (ret)
+			Err("isoc_init() submit_urb %d failed with error %d\n", i, ret);
+		else
+			Trace(TRACE_MEMORY, "URB 0x%p submitted.\n", pdev->sbuf[i].urb);
+	}
+
+	/* All is done... */
+	pdev->iso_init = 1;
+	Trace(TRACE_OPEN, "<< pwc_isoc_init()\n");
+	return 0;
+}
+
+static void pwc_isoc_cleanup(struct pwc_device *pdev)
+{
+	int i;
+
+	Trace(TRACE_OPEN, ">> pwc_isoc_cleanup()\n");
+	if (pdev == NULL)
+		return;
+
+	/* Unlinking ISOC buffers one by one */
+	for (i = 0; i < MAX_ISO_BUFS; i++) {
+		struct urb *urb;
+
+		urb = pdev->sbuf[i].urb;
+		if (urb != 0) {
+			if (pdev->iso_init) {
+				Trace(TRACE_MEMORY, "Unlinking URB %p\n", urb);
+				usb_kill_urb(urb);
+			}
+			Trace(TRACE_MEMORY, "Freeing URB\n");
+			usb_free_urb(urb);
+			pdev->sbuf[i].urb = NULL;
+		}
+	}
+
+	/* Stop camera, but only if we are sure the camera is still there (unplug
+	   is signalled by EPIPE) 
+	 */
+	if (pdev->error_status && pdev->error_status != EPIPE) {
+		Trace(TRACE_OPEN, "Setting alternate interface 0.\n");
+		usb_set_interface(pdev->udev, 0, 0);
+	}
+
+	pdev->iso_init = 0;
+	Trace(TRACE_OPEN, "<< pwc_isoc_cleanup()\n");
+}
+
+int pwc_try_video_mode(struct pwc_device *pdev, int width, int height, int new_fps, int new_compression, int new_snapshot)
+{
+	int ret, start;
+
+	/* Stop isoc stuff */
+	pwc_isoc_cleanup(pdev);
+	/* Reset parameters */
+	pwc_reset_buffers(pdev);
+	/* Try to set video mode... */
+	start = ret = pwc_set_video_mode(pdev, width, height, new_fps, new_compression, new_snapshot);
+	if (ret) { 
+	        Trace(TRACE_FLOW, "pwc_set_video_mode attempt 1 failed.\n");
+		/* That failed... restore old mode (we know that worked) */
+		start = pwc_set_video_mode(pdev, pdev->view.x, pdev->view.y, pdev->vframes, pdev->vcompression, pdev->vsnapshot);
+		if (start) {
+		        Trace(TRACE_FLOW, "pwc_set_video_mode attempt 2 failed.\n");
+		}
+	}
+	if (start == 0)
+	{
+		if (pwc_isoc_init(pdev) < 0)
+		{
+			Info("Failed to restart ISOC transfers in pwc_try_video_mode.\n");
+			ret = -EAGAIN; /* let's try again, who knows if it works a second time */
+		}
+	}
+	pdev->drop_frames++; /* try to avoid garbage during switch */
+	return ret; /* Return original error code */
+}
+
+
+/***************************************************************************/
+/* Video4Linux functions */
+
+static int pwc_video_open(struct inode *inode, struct file *file)
+{
+	int i;
+	struct video_device *vdev = video_devdata(file);
+	struct pwc_device *pdev;
+
+	Trace(TRACE_OPEN, ">> video_open called(vdev = 0x%p).\n", vdev);
+	
+	pdev = (struct pwc_device *)vdev->priv;
+	if (pdev == NULL)
+		BUG();
+	if (pdev->vopen)
+		return -EBUSY;
+	
+	down(&pdev->modlock);
+	if (!pdev->usb_init) {
+		Trace(TRACE_OPEN, "Doing first time initialization.\n");
+		pdev->usb_init = 1;
+		
+		if (pwc_trace & TRACE_OPEN)
+		{
+			/* Query sensor type */
+			const char *sensor_type = NULL;
+			int ret;
+
+			ret = pwc_get_cmos_sensor(pdev, &i);
+			if (ret >= 0)
+			{
+				switch(i) {
+				case 0x00:  sensor_type = "Hyundai CMOS sensor"; break;
+				case 0x20:  sensor_type = "Sony CCD sensor + TDA8787"; break;
+				case 0x2E:  sensor_type = "Sony CCD sensor + Exas 98L59"; break;
+				case 0x2F:  sensor_type = "Sony CCD sensor + ADI 9804"; break;
+				case 0x30:  sensor_type = "Sharp CCD sensor + TDA8787"; break;
+				case 0x3E:  sensor_type = "Sharp CCD sensor + Exas 98L59"; break;
+				case 0x3F:  sensor_type = "Sharp CCD sensor + ADI 9804"; break;
+				case 0x40:  sensor_type = "UPA 1021 sensor"; break;
+				case 0x100: sensor_type = "VGA sensor"; break;
+				case 0x101: sensor_type = "PAL MR sensor"; break;
+				default:    sensor_type = "unknown type of sensor"; break;
+				}
+			}
+			if (sensor_type != NULL)
+				Info("This %s camera is equipped with a %s (%d).\n", pdev->vdev->name, sensor_type, i);
+		}
+	}
+
+	/* Turn on camera */
+	if (power_save) {
+		i = pwc_camera_power(pdev, 1);
+		if (i < 0)
+			Info("Failed to restore power to the camera! (%d)\n", i);
+	}
+	/* Set LED on/off time */
+	if (pwc_set_leds(pdev, led_on, led_off) < 0)
+		Info("Failed to set LED on/off time.\n");
+	
+	pwc_construct(pdev); /* set min/max sizes correct */
+
+	/* So far, so good. Allocate memory. */
+	i = pwc_allocate_buffers(pdev);
+	if (i < 0) {
+		Trace(TRACE_OPEN, "Failed to allocate buffer memory.\n");
+		up(&pdev->modlock);
+		return i;
+	}
+	
+	/* Reset buffers & parameters */
+	pwc_reset_buffers(pdev);
+	for (i = 0; i < default_mbufs; i++)
+		pdev->image_used[i] = 0;
+	pdev->vframe_count = 0;
+	pdev->vframes_dumped = 0;
+	pdev->vframes_error = 0;
+	pdev->visoc_errors = 0;
+	pdev->error_status = 0;
+#if PWC_DEBUG
+	pdev->sequence = 0;
+#endif
+	pwc_construct(pdev); /* set min/max sizes correct */
+
+	/* Set some defaults */
+	pdev->vsnapshot = 0;
+
+	/* Start iso pipe for video; first try the last used video size
+	   (or the default one); if that fails try QCIF/10 or QSIF/10;
+	   it that fails too, give up.
+	 */
+	i = pwc_set_video_mode(pdev, pwc_image_sizes[pdev->vsize].x, pwc_image_sizes[pdev->vsize].y, pdev->vframes, pdev->vcompression, 0);
+	if (i)	{
+		Trace(TRACE_OPEN, "First attempt at set_video_mode failed.\n");
+		if (pdev->type == 730 || pdev->type == 740 || pdev->type == 750)
+			i = pwc_set_video_mode(pdev, pwc_image_sizes[PSZ_QSIF].x, pwc_image_sizes[PSZ_QSIF].y, 10, pdev->vcompression, 0);
+		else
+			i = pwc_set_video_mode(pdev, pwc_image_sizes[PSZ_QCIF].x, pwc_image_sizes[PSZ_QCIF].y, 10, pdev->vcompression, 0);
+	}
+	if (i) {
+		Trace(TRACE_OPEN, "Second attempt at set_video_mode failed.\n");
+		up(&pdev->modlock);
+		return i;
+	}
+	
+	i = pwc_isoc_init(pdev);
+	if (i) {
+		Trace(TRACE_OPEN, "Failed to init ISOC stuff = %d.\n", i);
+		up(&pdev->modlock);
+		return i;
+	}
+
+	pdev->vopen++;
+	file->private_data = vdev;
+	up(&pdev->modlock);
+	Trace(TRACE_OPEN, "<< video_open() returns 0.\n");
+	return 0;
+}
+
+/* Note that all cleanup is done in the reverse order as in _open */
+static int pwc_video_close(struct inode *inode, struct file *file)
+{
+	struct video_device *vdev = file->private_data;
+	struct pwc_device *pdev;
+	int i;
+
+	Trace(TRACE_OPEN, ">> video_close called(vdev = 0x%p).\n", vdev);
+
+	pdev = (struct pwc_device *)vdev->priv;
+	if (pdev->vopen == 0)
+		Info("video_close() called on closed device?\n");
+
+	/* Dump statistics, but only if a reasonable amount of frames were
+	   processed (to prevent endless log-entries in case of snap-shot
+	   programs)
+	 */
+	if (pdev->vframe_count > 20)
+		Info("Closing video device: %d frames received, dumped %d frames, %d frames with errors.\n", pdev->vframe_count, pdev->vframes_dumped, pdev->vframes_error);
+
+	switch (pdev->type)
+	 {
+	  case 675:
+	  case 680:
+	  case 690:
+	  case 720:
+	  case 730:
+	  case 740:
+	  case 750:
+/*	    pwc_dec23_exit();	*//* Timon & Kiara */
+	    break;
+	  case 645:
+	  case 646:
+/*	    pwc_dec1_exit(); */
+	    break;
+	 }
+
+	pwc_isoc_cleanup(pdev);
+	pwc_free_buffers(pdev);
+
+	/* Turn off LEDS and power down camera, but only when not unplugged */
+	if (pdev->error_status != EPIPE) {
+		/* Turn LEDs off */
+		if (pwc_set_leds(pdev, 0, 0) < 0)
+			Info("Failed to set LED on/off time.\n");
+		if (power_save) {
+			i = pwc_camera_power(pdev, 0);
+			if (i < 0)
+				Err("Failed to power down camera (%d)\n", i);
+		}
+	}
+	pdev->vopen = 0;
+	Trace(TRACE_OPEN, "<< video_close()\n");
+	return 0;
+}
+
+/*
+ *	FIXME: what about two parallel reads ????
+ *      ANSWER: Not supported. You can't open the device more than once,
+                despite what the V4L1 interface says. First, I don't see
+                the need, second there's no mechanism of alerting the
+                2nd/3rd/... process of events like changing image size.
+                And I don't see the point of blocking that for the
+                2nd/3rd/... process.
+                In multi-threaded environments reading parallel from any
+                device is tricky anyhow.
+ */
+
+static ssize_t pwc_video_read(struct file *file, char __user * buf,
+			  size_t count, loff_t *ppos)
+{
+	struct video_device *vdev = file->private_data;
+	struct pwc_device *pdev;
+	int noblock = file->f_flags & O_NONBLOCK;
+	DECLARE_WAITQUEUE(wait, current);
+        int bytes_to_read;
+
+	Trace(TRACE_READ, "video_read(0x%p, %p, %zu) called.\n", vdev, buf, count);
+	if (vdev == NULL)
+		return -EFAULT;
+	pdev = vdev->priv;
+	if (pdev == NULL)
+		return -EFAULT;
+	if (pdev->error_status)
+		return -pdev->error_status; /* Something happened, report what. */
+
+	/* In case we're doing partial reads, we don't have to wait for a frame */
+	if (pdev->image_read_pos == 0) {
+		/* Do wait queueing according to the (doc)book */
+		add_wait_queue(&pdev->frameq, &wait);
+		while (pdev->full_frames == NULL) {
+			/* Check for unplugged/etc. here */
+			if (pdev->error_status) {
+				remove_wait_queue(&pdev->frameq, &wait);
+				set_current_state(TASK_RUNNING);
+				return -pdev->error_status ;
+			}
+	                if (noblock) {
+	                	remove_wait_queue(&pdev->frameq, &wait);
+	                	set_current_state(TASK_RUNNING);
+	                	return -EWOULDBLOCK;
+	                }
+	                if (signal_pending(current)) {
+	                	remove_wait_queue(&pdev->frameq, &wait);
+	                	set_current_state(TASK_RUNNING);
+	                	return -ERESTARTSYS;
+	                }
+	                schedule();
+	               	set_current_state(TASK_INTERRUPTIBLE);
+		}
+		remove_wait_queue(&pdev->frameq, &wait);
+		set_current_state(TASK_RUNNING);
+                                                                                                                                                                                
+		/* Decompress and release frame */
+		if (pwc_handle_frame(pdev))
+			return -EFAULT;
+	}
+
+	Trace(TRACE_READ, "Copying data to user space.\n");
+	if (pdev->vpalette == VIDEO_PALETTE_RAW)
+		bytes_to_read = pdev->frame_size;
+	else
+ 		bytes_to_read = pdev->view.size;
+
+	/* copy bytes to user space; we allow for partial reads */
+	if (count + pdev->image_read_pos > bytes_to_read)
+		count = bytes_to_read - pdev->image_read_pos;
+	if (copy_to_user(buf, pdev->image_ptr[pdev->fill_image] + pdev->image_read_pos, count))
+		return -EFAULT;
+	pdev->image_read_pos += count;
+	if (pdev->image_read_pos >= bytes_to_read) { /* All data has been read */
+		pdev->image_read_pos = 0;
+		pwc_next_image(pdev);
+	}
+	return count;
+}
+
+static unsigned int pwc_video_poll(struct file *file, poll_table *wait)
+{
+	struct video_device *vdev = file->private_data;
+	struct pwc_device *pdev;
+
+	if (vdev == NULL)
+		return -EFAULT;
+	pdev = vdev->priv;
+	if (pdev == NULL)
+		return -EFAULT;
+
+	poll_wait(file, &pdev->frameq, wait);
+	if (pdev->error_status)
+		return POLLERR;
+	if (pdev->full_frames != NULL) /* we have frames waiting */
+		return (POLLIN | POLLRDNORM);
+
+	return 0;
+}
+
+static int pwc_video_do_ioctl(struct inode *inode, struct file *file,
+			      unsigned int cmd, void *arg)
+{
+	struct video_device *vdev = file->private_data;
+	struct pwc_device *pdev;
+	DECLARE_WAITQUEUE(wait, current);
+
+	if (vdev == NULL)
+		return -EFAULT;
+	pdev = vdev->priv;
+	if (pdev == NULL)
+		return -EFAULT;
+
+	switch (cmd) {
+		/* Query cabapilities */
+		case VIDIOCGCAP:
+		{
+			struct video_capability *caps = arg;
+
+			strcpy(caps->name, vdev->name);
+			caps->type = VID_TYPE_CAPTURE;
+			caps->channels = 1;
+			caps->audios = 1;
+			caps->minwidth  = pdev->view_min.x;
+			caps->minheight = pdev->view_min.y;
+			caps->maxwidth  = pdev->view_max.x;
+			caps->maxheight = pdev->view_max.y;
+			break;
+		}
+
+		/* Channel functions (simulate 1 channel) */
+		case VIDIOCGCHAN:
+		{
+			struct video_channel *v = arg;
+
+			if (v->channel != 0)
+				return -EINVAL;
+			v->flags = 0;
+			v->tuners = 0;
+			v->type = VIDEO_TYPE_CAMERA;
+			strcpy(v->name, "Webcam");
+			return 0;
+		}
+
+		case VIDIOCSCHAN:
+		{
+			/* The spec says the argument is an integer, but
+			   the bttv driver uses a video_channel arg, which
+			   makes sense becasue it also has the norm flag.
+			 */
+			struct video_channel *v = arg;
+			if (v->channel != 0)
+				return -EINVAL;
+			return 0;
+		}
+
+
+		/* Picture functions; contrast etc. */
+		case VIDIOCGPICT:
+		{
+			struct video_picture *p = arg;
+			int val;
+
+			val = pwc_get_brightness(pdev);
+			if (val >= 0)
+				p->brightness = val;
+			else
+				p->brightness = 0xffff;
+			val = pwc_get_contrast(pdev);
+			if (val >= 0)
+				p->contrast = val;
+			else
+				p->contrast = 0xffff;
+			/* Gamma, Whiteness, what's the difference? :) */
+			val = pwc_get_gamma(pdev);
+			if (val >= 0)
+				p->whiteness = val;
+			else
+				p->whiteness = 0xffff;
+			val = pwc_get_saturation(pdev);
+			if (val >= 0)
+				p->colour = val;
+			else
+				p->colour = 0xffff;
+			p->depth = 24;
+			p->palette = pdev->vpalette;
+			p->hue = 0xFFFF; /* N/A */
+			break;
+		}
+
+		case VIDIOCSPICT:
+		{
+			struct video_picture *p = arg;
+			/*
+			 *	FIXME:	Suppose we are mid read
+			        ANSWER: No problem: the firmware of the camera
+			                can handle brightness/contrast/etc
+			                changes at _any_ time, and the palette
+			                is used exactly once in the uncompress
+			                routine.
+			 */
+			pwc_set_brightness(pdev, p->brightness);
+			pwc_set_contrast(pdev, p->contrast);
+			pwc_set_gamma(pdev, p->whiteness);
+			pwc_set_saturation(pdev, p->colour);
+			if (p->palette && p->palette != pdev->vpalette) {
+				switch (p->palette) {
+					case VIDEO_PALETTE_YUV420P:
+					case VIDEO_PALETTE_RAW:
+						pdev->vpalette = p->palette;
+						return pwc_try_video_mode(pdev, pdev->image.x, pdev->image.y, pdev->vframes, pdev->vcompression, pdev->vsnapshot);
+						break;
+					default:
+						return -EINVAL;
+						break;
+				}
+			}
+			break;
+		}
+
+		/* Window/size parameters */		
+		case VIDIOCGWIN:
+		{
+			struct video_window *vw = arg;
+			
+			vw->x = 0;
+			vw->y = 0;
+			vw->width = pdev->view.x;
+			vw->height = pdev->view.y;
+			vw->chromakey = 0;
+			vw->flags = (pdev->vframes << PWC_FPS_SHIFT) | 
+			           (pdev->vsnapshot ? PWC_FPS_SNAPSHOT : 0);
+			break;
+		}
+		
+		case VIDIOCSWIN:
+		{
+			struct video_window *vw = arg;
+			int fps, snapshot, ret;
+
+			fps = (vw->flags & PWC_FPS_FRMASK) >> PWC_FPS_SHIFT;
+			snapshot = vw->flags & PWC_FPS_SNAPSHOT;
+			if (fps == 0)
+				fps = pdev->vframes;
+			if (pdev->view.x == vw->width && pdev->view.y && fps == pdev->vframes && snapshot == pdev->vsnapshot)
+				return 0;
+			ret = pwc_try_video_mode(pdev, vw->width, vw->height, fps, pdev->vcompression, snapshot);
+			if (ret)
+				return ret;
+			break;		
+		}
+		
+		/* We don't have overlay support (yet) */
+		case VIDIOCGFBUF:
+		{
+			struct video_buffer *vb = arg;
+
+			memset(vb,0,sizeof(*vb));
+			break;
+		}
+
+		/* mmap() functions */
+		case VIDIOCGMBUF:
+		{
+			/* Tell the user program how much memory is needed for a mmap() */
+			struct video_mbuf *vm = arg;
+			int i;
+
+			memset(vm, 0, sizeof(*vm));
+			vm->size = default_mbufs * pdev->len_per_image;
+			vm->frames = default_mbufs; /* double buffering should be enough for most applications */
+			for (i = 0; i < default_mbufs; i++)
+				vm->offsets[i] = i * pdev->len_per_image;
+			break;
+		}
+
+		case VIDIOCMCAPTURE:
+		{
+			/* Start capture into a given image buffer (called 'frame' in video_mmap structure) */
+			struct video_mmap *vm = arg;
+
+			Trace(TRACE_READ, "VIDIOCMCAPTURE: %dx%d, frame %d, format %d\n", vm->width, vm->height, vm->frame, vm->format);
+			if (vm->frame < 0 || vm->frame >= default_mbufs)
+				return -EINVAL;
+
+			/* xawtv is nasty. It probes the available palettes
+			   by setting a very small image size and trying
+			   various palettes... The driver doesn't support
+			   such small images, so I'm working around it.
+			 */
+			if (vm->format)
+			{
+				switch (vm->format)
+				{
+					case VIDEO_PALETTE_YUV420P:
+					case VIDEO_PALETTE_RAW:
+						break;
+					default:
+						return -EINVAL;
+						break;
+				}
+			}
+
+			if ((vm->width != pdev->view.x || vm->height != pdev->view.y) &&
+			    (vm->width >= pdev->view_min.x && vm->height >= pdev->view_min.y)) {
+				int ret;
+
+				Trace(TRACE_OPEN, "VIDIOCMCAPTURE: changing size to please xawtv :-(.\n");
+				ret = pwc_try_video_mode(pdev, vm->width, vm->height, pdev->vframes, pdev->vcompression, pdev->vsnapshot);
+				if (ret)
+					return ret;
+			} /* ... size mismatch */
+
+			/* FIXME: should we lock here? */
+			if (pdev->image_used[vm->frame])
+				return -EBUSY;	/* buffer wasn't available. Bummer */
+			pdev->image_used[vm->frame] = 1;
+
+			/* Okay, we're done here. In the SYNC call we wait until a 
+			   frame comes available, then expand image into the given 
+			   buffer.
+			   In contrast to the CPiA cam the Philips cams deliver a
+			   constant stream, almost like a grabber card. Also,
+			   we have separate buffers for the rawdata and the image,
+			   meaning we can nearly always expand into the requested buffer.
+			 */
+			Trace(TRACE_READ, "VIDIOCMCAPTURE done.\n");
+			break;
+		}
+
+		case VIDIOCSYNC:
+		{
+			/* The doc says: "Whenever a buffer is used it should
+			   call VIDIOCSYNC to free this frame up and continue."
+			   
+			   The only odd thing about this whole procedure is 
+			   that MCAPTURE flags the buffer as "in use", and
+			   SYNC immediately unmarks it, while it isn't 
+			   after SYNC that you know that the buffer actually
+			   got filled! So you better not start a CAPTURE in
+			   the same frame immediately (use double buffering). 
+			   This is not a problem for this cam, since it has 
+			   extra intermediate buffers, but a hardware 
+			   grabber card will then overwrite the buffer 
+			   you're working on.
+			 */
+			int *mbuf = arg;
+			int ret;
+
+			Trace(TRACE_READ, "VIDIOCSYNC called (%d).\n", *mbuf);
+
+			/* bounds check */
+			if (*mbuf < 0 || *mbuf >= default_mbufs)
+				return -EINVAL;
+			/* check if this buffer was requested anyway */
+			if (pdev->image_used[*mbuf] == 0)
+				return -EINVAL;
+
+			/* Add ourselves to the frame wait-queue.
+			   
+			   FIXME: needs auditing for safety.
+			   QUESTION: In what respect? I think that using the
+			             frameq is safe now.
+			 */
+			add_wait_queue(&pdev->frameq, &wait);
+			while (pdev->full_frames == NULL) {
+				if (pdev->error_status) {
+					remove_wait_queue(&pdev->frameq, &wait);
+					set_current_state(TASK_RUNNING);
+					return -pdev->error_status;
+				}
+			
+	                	if (signal_pending(current)) {
+	                		remove_wait_queue(&pdev->frameq, &wait);
+		                	set_current_state(TASK_RUNNING);
+		                	return -ERESTARTSYS;
+	        	        }
+	                	schedule();
+		                set_current_state(TASK_INTERRUPTIBLE);
+			}
+			remove_wait_queue(&pdev->frameq, &wait);
+			set_current_state(TASK_RUNNING);
+				
+			/* The frame is ready. Expand in the image buffer 
+			   requested by the user. I don't care if you 
+			   mmap() 5 buffers and request data in this order: 
+			   buffer 4 2 3 0 1 2 3 0 4 3 1 . . .
+			   Grabber hardware may not be so forgiving.
+			 */
+			Trace(TRACE_READ, "VIDIOCSYNC: frame ready.\n");
+			pdev->fill_image = *mbuf; /* tell in which buffer we want the image to be expanded */
+			/* Decompress, etc */
+			ret = pwc_handle_frame(pdev);
+			pdev->image_used[*mbuf] = 0;
+			if (ret)
+				return -EFAULT;
+			break;
+		}
+		
+		case VIDIOCGAUDIO:
+		{
+			struct video_audio *v = arg;
+			
+			strcpy(v->name, "Microphone");
+			v->audio = -1; /* unknown audio minor */
+			v->flags = 0;
+			v->mode = VIDEO_SOUND_MONO;
+			v->volume = 0;
+			v->bass = 0;
+			v->treble = 0;
+			v->balance = 0x8000;
+			v->step = 1;
+			break;	
+		}
+		
+		case VIDIOCSAUDIO:
+		{
+			/* Dummy: nothing can be set */
+			break;
+		}
+		
+		case VIDIOCGUNIT:
+		{
+			struct video_unit *vu = arg;
+			
+			vu->video = pdev->vdev->minor & 0x3F;
+			vu->audio = -1; /* not known yet */
+			vu->vbi = -1;
+			vu->radio = -1;
+			vu->teletext = -1;
+			break;
+		}
+		default:
+			return pwc_ioctl(pdev, cmd, arg);
+	} /* ..switch */
+	return 0;
+}	
+
+static int pwc_video_ioctl(struct inode *inode, struct file *file,
+			   unsigned int cmd, unsigned long arg)
+{
+	return video_usercopy(inode, file, cmd, arg, pwc_video_do_ioctl);
+}
+
+
+static int pwc_video_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	struct video_device *vdev = file->private_data;
+	struct pwc_device *pdev;
+	unsigned long start = vma->vm_start;
+	unsigned long size  = vma->vm_end-vma->vm_start;
+	unsigned long page, pos;
+	
+	Trace(TRACE_MEMORY, "mmap(0x%p, 0x%lx, %lu) called.\n", vdev, start, size);
+	pdev = vdev->priv;
+	
+	vma->vm_flags |= VM_IO;
+
+	pos = (unsigned long)pdev->image_data;
+	while (size > 0) {
+		page = vmalloc_to_pfn((void *)pos);
+		if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED))
+			return -EAGAIN;
+
+		start += PAGE_SIZE;
+		pos += PAGE_SIZE;
+		if (size > PAGE_SIZE)
+			size -= PAGE_SIZE;
+		else
+			size = 0;
+	}
+
+	return 0;
+}
+
+/***************************************************************************/
+/* USB functions */
+
+/* This function gets called when a new device is plugged in or the usb core
+ * is loaded.
+ */
+
+static int usb_pwc_probe(struct usb_interface *intf, const struct usb_device_id *id)
+{
+	struct usb_device *udev = interface_to_usbdev(intf);
+	struct pwc_device *pdev = NULL;
+	int vendor_id, product_id, type_id;
+	int i, hint;
+	int features = 0;
+	int video_nr = -1; /* default: use next available device */
+	char serial_number[30], *name;
+
+	/* Check if we can handle this device */
+	Trace(TRACE_PROBE, "probe() called [%04X %04X], if %d\n", 
+		le16_to_cpu(udev->descriptor.idVendor),
+		le16_to_cpu(udev->descriptor.idProduct),
+		intf->altsetting->desc.bInterfaceNumber);
+
+	/* the interfaces are probed one by one. We are only interested in the
+	   video interface (0) now.
+	   Interface 1 is the Audio Control, and interface 2 Audio itself.
+	 */
+	if (intf->altsetting->desc.bInterfaceNumber > 0)
+		return -ENODEV;
+
+	vendor_id = le16_to_cpu(udev->descriptor.idVendor);
+	product_id = le16_to_cpu(udev->descriptor.idProduct);
+
+	if (vendor_id == 0x0471) {
+		switch (product_id) {
+		case 0x0302:
+			Info("Philips PCA645VC USB webcam detected.\n");
+			name = "Philips 645 webcam";
+			type_id = 645;
+			break;
+		case 0x0303:
+			Info("Philips PCA646VC USB webcam detected.\n");
+			name = "Philips 646 webcam";
+			type_id = 646;
+			break;
+		case 0x0304:
+			Info("Askey VC010 type 2 USB webcam detected.\n");
+			name = "Askey VC010 webcam";
+			type_id = 646;
+			break;
+		case 0x0307:
+			Info("Philips PCVC675K (Vesta) USB webcam detected.\n");
+			name = "Philips 675 webcam";
+			type_id = 675;
+			break;
+		case 0x0308:
+			Info("Philips PCVC680K (Vesta Pro) USB webcam detected.\n");
+			name = "Philips 680 webcam";
+			type_id = 680;
+			break;
+		case 0x030C:
+			Info("Philips PCVC690K (Vesta Pro Scan) USB webcam detected.\n");
+			name = "Philips 690 webcam";
+			type_id = 690;
+			break;
+		case 0x0310:
+			Info("Philips PCVC730K (ToUCam Fun)/PCVC830 (ToUCam II) USB webcam detected.\n");
+			name = "Philips 730 webcam";
+			type_id = 730;
+			break;
+		case 0x0311:
+			Info("Philips PCVC740K (ToUCam Pro)/PCVC840 (ToUCam II) USB webcam detected.\n");
+			name = "Philips 740 webcam";
+			type_id = 740;
+			break;
+		case 0x0312:
+			Info("Philips PCVC750K (ToUCam Pro Scan) USB webcam detected.\n");
+			name = "Philips 750 webcam";
+			type_id = 750;
+			break;
+		case 0x0313:
+			Info("Philips PCVC720K/40 (ToUCam XS) USB webcam detected.\n");
+			name = "Philips 720K/40 webcam";
+			type_id = 720;
+			break;
+		default:
+			return -ENODEV;
+			break;
+		}
+	}
+	else if (vendor_id == 0x069A) {
+		switch(product_id) {
+		case 0x0001:
+			Info("Askey VC010 type 1 USB webcam detected.\n");
+			name = "Askey VC010 webcam";
+			type_id = 645;
+			break;
+		default:
+			return -ENODEV;
+			break;
+		}
+	}
+	else if (vendor_id == 0x046d) {
+		switch(product_id) {
+		case 0x08b0:
+			Info("Logitech QuickCam Pro 3000 USB webcam detected.\n");
+			name = "Logitech QuickCam Pro 3000";
+			type_id = 740; /* CCD sensor */
+			break;
+		case 0x08b1:
+			Info("Logitech QuickCam Notebook Pro USB webcam detected.\n");
+			name = "Logitech QuickCam Notebook Pro";
+			type_id = 740; /* CCD sensor */
+			break;
+		case 0x08b2:
+			Info("Logitech QuickCam 4000 Pro USB webcam detected.\n");
+			name = "Logitech QuickCam Pro 4000";
+			type_id = 740; /* CCD sensor */
+			break;
+		case 0x08b3:
+			Info("Logitech QuickCam Zoom USB webcam detected.\n");
+			name = "Logitech QuickCam Zoom";
+			type_id = 740; /* CCD sensor */
+			break;
+		case 0x08B4:
+			Info("Logitech QuickCam Zoom (new model) USB webcam detected.\n");
+			name = "Logitech QuickCam Zoom";
+			type_id = 740; /* CCD sensor */
+			break;
+		case 0x08b5:
+			Info("Logitech QuickCam Orbit/Sphere USB webcam detected.\n");
+			name = "Logitech QuickCam Orbit";
+			type_id = 740; /* CCD sensor */
+			features |= FEATURE_MOTOR_PANTILT;
+			break;
+		case 0x08b6:
+		case 0x08b7:
+		case 0x08b8:
+			Info("Logitech QuickCam detected (reserved ID).\n");
+			name = "Logitech QuickCam (res.)";
+			type_id = 730; /* Assuming CMOS */
+			break;
+        	default:
+			return -ENODEV;
+        		break;
+        	}
+        }
+	else if (vendor_id == 0x055d) {
+		/* I don't know the difference between the C10 and the C30;
+		   I suppose the difference is the sensor, but both cameras
+		   work equally well with a type_id of 675
+		 */
+		switch(product_id) {
+		case 0x9000:
+			Info("Samsung MPC-C10 USB webcam detected.\n");
+			name = "Samsung MPC-C10";
+			type_id = 675;
+			break;
+		case 0x9001:
+			Info("Samsung MPC-C30 USB webcam detected.\n");
+			name = "Samsung MPC-C30";
+			type_id = 675;
+			break;
+		default:
+			return -ENODEV;
+			break;
+		}
+	}
+	else if (vendor_id == 0x041e) {
+		switch(product_id) {
+		case 0x400c:
+			Info("Creative Labs Webcam 5 detected.\n");
+			name = "Creative Labs Webcam 5";
+			type_id = 730;
+			break;
+		case 0x4011:
+			Info("Creative Labs Webcam Pro Ex detected.\n");
+			name = "Creative Labs Webcam Pro Ex";
+			type_id = 740;
+			break;
+		default:
+			return -ENODEV;
+			break;
+		}
+	}
+	else if (vendor_id == 0x04cc) {
+		switch(product_id) {
+		case 0x8116:
+			Info("Sotec Afina Eye USB webcam detected.\n");
+			name = "Sotec Afina Eye";
+			type_id = 730;
+			break;
+		default:
+			return -ENODEV;
+			break;
+		}
+	}
+	else if (vendor_id == 0x06be) {
+		switch(product_id) {
+		case 0x8116:
+			/* This is essentially the same cam as the Sotec Afina Eye */
+			Info("AME Co. Afina Eye USB webcam detected.\n");
+			name = "AME Co. Afina Eye";
+			type_id = 750;
+			break;
+		default:
+			return -ENODEV;
+			break;
+		}
+	
+	}
+	else if (vendor_id == 0x0d81) {
+		switch(product_id) {
+		case 0x1900:
+			Info("Visionite VCS-UC300 USB webcam detected.\n");
+			name = "Visionite VCS-UC300";
+			type_id = 740; /* CCD sensor */
+			break;
+		case 0x1910:
+			Info("Visionite VCS-UM100 USB webcam detected.\n");
+			name = "Visionite VCS-UM100";
+			type_id = 730; /* CMOS sensor */
+			break;
+		default:
+			return -ENODEV;
+			break;
+		}
+	}
+	else 
+		return -ENODEV; /* Not any of the know types; but the list keeps growing. */
+
+	memset(serial_number, 0, 30);
+	usb_string(udev, udev->descriptor.iSerialNumber, serial_number, 29);
+	Trace(TRACE_PROBE, "Device serial number is %s\n", serial_number);
+
+	if (udev->descriptor.bNumConfigurations > 1)
+		Info("Warning: more than 1 configuration available.\n");
+
+	/* Allocate structure, initialize pointers, mutexes, etc. and link it to the usb_device */
+	pdev = kzalloc(sizeof(struct pwc_device), GFP_KERNEL);
+	if (pdev == NULL) {
+		Err("Oops, could not allocate memory for pwc_device.\n");
+		return -ENOMEM;
+	}
+	pdev->type = type_id;
+	pdev->vsize = default_size;
+	pdev->vframes = default_fps;
+	strcpy(pdev->serial, serial_number);
+	pdev->features = features;
+	if (vendor_id == 0x046D && product_id == 0x08B5)
+	{
+		/* Logitech QuickCam Orbit
+	           The ranges have been determined experimentally; they may differ from cam to cam.
+	           Also, the exact ranges left-right and up-down are different for my cam
+	          */
+		pdev->angle_range.pan_min  = -7000;
+		pdev->angle_range.pan_max  =  7000;
+		pdev->angle_range.tilt_min = -3000;
+		pdev->angle_range.tilt_max =  2500;
+	}
+
+	init_MUTEX(&pdev->modlock);
+	spin_lock_init(&pdev->ptrlock);
+
+	pdev->udev = udev;
+	init_waitqueue_head(&pdev->frameq);
+	pdev->vcompression = pwc_preferred_compression;
+
+	/* Allocate video_device structure */
+	pdev->vdev = video_device_alloc();
+	if (pdev->vdev == 0)
+	{
+		Err("Err, cannot allocate video_device struture. Failing probe.");
+		kfree(pdev);
+		return -ENOMEM;
+	}
+	memcpy(pdev->vdev, &pwc_template, sizeof(pwc_template));
+	strcpy(pdev->vdev->name, name);
+	pdev->vdev->owner = THIS_MODULE;
+	video_set_drvdata(pdev->vdev, pdev);
+
+	pdev->release = le16_to_cpu(udev->descriptor.bcdDevice);
+	Trace(TRACE_PROBE, "Release: %04x\n", pdev->release);
+
+	/* Now search device_hint[] table for a match, so we can hint a node number. */
+	for (hint = 0; hint < MAX_DEV_HINTS; hint++) {
+		if (((device_hint[hint].type == -1) || (device_hint[hint].type == pdev->type)) &&
+		     (device_hint[hint].pdev == NULL)) {
+			/* so far, so good... try serial number */
+			if ((device_hint[hint].serial_number[0] == '*') || !strcmp(device_hint[hint].serial_number, serial_number)) {
+			    	/* match! */
+			    	video_nr = device_hint[hint].device_node;
+			    	Trace(TRACE_PROBE, "Found hint, will try to register as /dev/video%d\n", video_nr);
+			    	break;
+			}
+		}
+	}
+
+	pdev->vdev->release = video_device_release;
+	i = video_register_device(pdev->vdev, VFL_TYPE_GRABBER, video_nr);
+	if (i < 0) {
+		Err("Failed to register as video device (%d).\n", i);
+		video_device_release(pdev->vdev); /* Drip... drip... drip... */
+		kfree(pdev); /* Oops, no memory leaks please */
+		return -EIO;
+	}
+	else {
+		Info("Registered as /dev/video%d.\n", pdev->vdev->minor & 0x3F);
+	}
+
+	/* occupy slot */
+	if (hint < MAX_DEV_HINTS) 
+		device_hint[hint].pdev = pdev;
+
+	Trace(TRACE_PROBE, "probe() function returning struct at 0x%p.\n", pdev);
+	usb_set_intfdata (intf, pdev);
+	return 0;
+}
+
+/* The user janked out the cable... */
+static void usb_pwc_disconnect(struct usb_interface *intf)
+{
+	struct pwc_device *pdev;
+	int hint;
+
+	lock_kernel();
+	pdev = usb_get_intfdata (intf);
+	usb_set_intfdata (intf, NULL);
+	if (pdev == NULL) {
+		Err("pwc_disconnect() Called without private pointer.\n");
+		goto disconnect_out;
+	}
+	if (pdev->udev == NULL) {
+		Err("pwc_disconnect() already called for %p\n", pdev);
+		goto disconnect_out;
+	}
+	if (pdev->udev != interface_to_usbdev(intf)) {
+		Err("pwc_disconnect() Woops: pointer mismatch udev/pdev.\n");
+		goto disconnect_out;
+	}
+#ifdef PWC_MAGIC	
+	if (pdev->magic != PWC_MAGIC) {
+		Err("pwc_disconnect() Magic number failed. Consult your scrolls and try again.\n");
+		goto disconnect_out;
+	}
+#endif
+	
+	/* We got unplugged; this is signalled by an EPIPE error code */
+	if (pdev->vopen) {
+		Info("Disconnected while webcam is in use!\n");
+		pdev->error_status = EPIPE;
+	}
+
+	/* Alert waiting processes */
+	wake_up_interruptible(&pdev->frameq);
+	/* Wait until device is closed */
+	while (pdev->vopen)
+		schedule();
+	/* Device is now closed, so we can safely unregister it */
+	Trace(TRACE_PROBE, "Unregistering video device in disconnect().\n");
+	video_unregister_device(pdev->vdev);
+
+	/* Free memory (don't set pdev to 0 just yet) */
+	kfree(pdev);
+
+disconnect_out:
+	/* search device_hint[] table if we occupy a slot, by any chance */
+	for (hint = 0; hint < MAX_DEV_HINTS; hint++)
+		if (device_hint[hint].pdev == pdev)
+			device_hint[hint].pdev = NULL;
+
+	unlock_kernel();
+}
+
+
+/* *grunt* We have to do atoi ourselves :-( */
+static int pwc_atoi(const char *s)
+{
+	int k = 0;
+
+	k = 0;
+	while (*s != '\0' && *s >= '0' && *s <= '9') {
+		k = 10 * k + (*s - '0');
+		s++;
+	}
+	return k;
+}
+
+
+/* 
+ * Initialization code & module stuff 
+ */
+
+static char size[10];
+static int fps = 0;
+static int fbufs = 0;
+static int mbufs = 0;
+static int trace = -1;
+static int compression = -1;
+static int leds[2] = { -1, -1 };
+static char *dev_hint[MAX_DEV_HINTS] = { };
+
+module_param_string(size, size, sizeof(size), 0);
+MODULE_PARM_DESC(size, "Initial image size. One of sqcif, qsif, qcif, sif, cif, vga");
+module_param(fps, int, 0000);
+MODULE_PARM_DESC(fps, "Initial frames per second. Varies with model, useful range 5-30");
+module_param(fbufs, int, 0000);
+MODULE_PARM_DESC(fbufs, "Number of internal frame buffers to reserve");
+module_param(mbufs, int, 0000);
+MODULE_PARM_DESC(mbufs, "Number of external (mmap()ed) image buffers");
+module_param(trace, int, 0000);
+MODULE_PARM_DESC(trace, "For debugging purposes");
+module_param(power_save, bool, 0000);
+MODULE_PARM_DESC(power_save, "Turn power save feature in camera on or off");
+module_param(compression, int, 0000);
+MODULE_PARM_DESC(compression, "Preferred compression quality. Range 0 (uncompressed) to 3 (high compression)");
+module_param_array(leds, int, NULL, 0000);
+MODULE_PARM_DESC(leds, "LED on,off time in milliseconds");
+module_param_array(dev_hint, charp, NULL, 0000);
+MODULE_PARM_DESC(dev_hint, "Device node hints");
+
+MODULE_DESCRIPTION("Philips & OEM USB webcam driver");
+MODULE_AUTHOR("Luc Saillard <luc@saillard.org>");
+MODULE_LICENSE("GPL");
+
+static int __init usb_pwc_init(void)
+{
+	int i, sz;
+	char *sizenames[PSZ_MAX] = { "sqcif", "qsif", "qcif", "sif", "cif", "vga" };
+
+	Info("Philips webcam module version " PWC_VERSION " loaded.\n");
+	Info("Supports Philips PCA645/646, PCVC675/680/690, PCVC720[40]/730/740/750 & PCVC830/840.\n");
+	Info("Also supports the Askey VC010, various Logitech Quickcams, Samsung MPC-C10 and MPC-C30,\n");
+	Info("the Creative WebCam 5 & Pro Ex, SOTEC Afina Eye and Visionite VCS-UC300 and VCS-UM100.\n");
+
+	if (fps) {
+		if (fps < 4 || fps > 30) {
+			Err("Framerate out of bounds (4-30).\n");
+			return -EINVAL;
+		}
+		default_fps = fps;
+		Info("Default framerate set to %d.\n", default_fps);
+	}
+
+	if (size[0]) {
+		/* string; try matching with array */
+		for (sz = 0; sz < PSZ_MAX; sz++) {
+			if (!strcmp(sizenames[sz], size)) { /* Found! */
+				default_size = sz;
+				break;
+			}
+		}
+		if (sz == PSZ_MAX) {
+			Err("Size not recognized; try size=[sqcif | qsif | qcif | sif | cif | vga].\n");
+			return -EINVAL;
+		}
+		Info("Default image size set to %s [%dx%d].\n", sizenames[default_size], pwc_image_sizes[default_size].x, pwc_image_sizes[default_size].y);
+	}
+	if (mbufs) {
+		if (mbufs < 1 || mbufs > MAX_IMAGES) {
+			Err("Illegal number of mmap() buffers; use a number between 1 and %d.\n", MAX_IMAGES);
+			return -EINVAL;
+		}
+		default_mbufs = mbufs;
+		Info("Number of image buffers set to %d.\n", default_mbufs);
+	}
+	if (fbufs) {
+		if (fbufs < 2 || fbufs > MAX_FRAMES) {
+			Err("Illegal number of frame buffers; use a number between 2 and %d.\n", MAX_FRAMES);
+			return -EINVAL;
+		}
+		default_fbufs = fbufs;
+		Info("Number of frame buffers set to %d.\n", default_fbufs);
+	}
+	if (trace >= 0) {
+		Info("Trace options: 0x%04x\n", trace);
+		pwc_trace = trace;
+	}
+	if (compression >= 0) {
+		if (compression > 3) {
+			Err("Invalid compression setting; use a number between 0 (uncompressed) and 3 (high).\n");
+			return -EINVAL;
+		}
+		pwc_preferred_compression = compression;
+		Info("Preferred compression set to %d.\n", pwc_preferred_compression);
+	}
+	if (power_save)
+		Info("Enabling power save on open/close.\n");
+	if (leds[0] >= 0)
+		led_on = leds[0];
+	if (leds[1] >= 0)
+		led_off = leds[1];
+
+	/* Big device node whoopla. Basically, it allows you to assign a
+	   device node (/dev/videoX) to a camera, based on its type
+	   & serial number. The format is [type[.serialnumber]:]node.
+
+	   Any camera that isn't matched by these rules gets the next
+	   available free device node.
+	 */
+	for (i = 0; i < MAX_DEV_HINTS; i++) {
+		char *s, *colon, *dot;
+
+		/* This loop also initializes the array */
+		device_hint[i].pdev = NULL;
+		s = dev_hint[i];
+		if (s != NULL && *s != '\0') {
+			device_hint[i].type = -1; /* wildcard */
+			strcpy(device_hint[i].serial_number, "*");
+
+			/* parse string: chop at ':' & '/' */
+			colon = dot = s;
+			while (*colon != '\0' && *colon != ':')
+				colon++;
+			while (*dot != '\0' && *dot != '.')
+				dot++;
+			/* Few sanity checks */
+			if (*dot != '\0' && dot > colon) {
+				Err("Malformed camera hint: the colon must be after the dot.\n");
+				return -EINVAL;
+			}
+
+			if (*colon == '\0') {
+				/* No colon */
+				if (*dot != '\0') {
+					Err("Malformed camera hint: no colon + device node given.\n");
+					return -EINVAL;
+				}
+				else {
+					/* No type or serial number specified, just a number. */
+					device_hint[i].device_node = pwc_atoi(s);
+				}
+			}
+			else {
+				/* There's a colon, so we have at least a type and a device node */
+				device_hint[i].type = pwc_atoi(s);
+				device_hint[i].device_node = pwc_atoi(colon + 1);
+				if (*dot != '\0') {
+					/* There's a serial number as well */
+					int k;
+					
+					dot++;
+					k = 0;
+					while (*dot != ':' && k < 29) {
+						device_hint[i].serial_number[k++] = *dot;
+						dot++;
+					}
+					device_hint[i].serial_number[k] = '\0';
+				}
+			}
+#if PWC_DEBUG		
+			Debug("device_hint[%d]:\n", i);
+			Debug("  type    : %d\n", device_hint[i].type);
+			Debug("  serial# : %s\n", device_hint[i].serial_number);
+			Debug("  node    : %d\n", device_hint[i].device_node);
+#endif			
+		}
+		else
+			device_hint[i].type = 0; /* not filled */
+	} /* ..for MAX_DEV_HINTS */
+
+ 	Trace(TRACE_PROBE, "Registering driver at address 0x%p.\n", &pwc_driver);
+	return usb_register(&pwc_driver);
+}
+
+static void __exit usb_pwc_exit(void)
+{
+	Trace(TRACE_MODULE, "Deregistering driver.\n");
+	usb_deregister(&pwc_driver);
+	Info("Philips webcam module removed.\n");
+}
+
+module_init(usb_pwc_init);
+module_exit(usb_pwc_exit);
+