patch-2.4.23 linux-2.4.23/drivers/usb/w9968cf.c

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diff -urN linux-2.4.22/drivers/usb/w9968cf.c linux-2.4.23/drivers/usb/w9968cf.c
@@ -0,0 +1,3989 @@
+/***************************************************************************
+ * Video4Linux driver for W996[87]CF JPEG USB Dual Mode Camera Chip.       *
+ *                                                                         *
+ * Copyright (C) 2002 2003 by Luca Risolia <luca_ing@libero.it>            *
+ *                                                                         *
+ * - Memory management code from bttv driver by Ralph Metzler,             *
+ *   Marcus Metzler and Gerd Knorr.                                        *
+ * - I2C interface to kernel, high-level CMOS sensor control routines and  *
+ *   some symbolic names from OV511 driver by Mark W. McClelland.          *
+ * - Low-level I2C fast write function by Piotr Czerczak.                  *
+ * - Low-level I2C read function by Frédéric Jouault.                      *
+ *                                                                         *
+ * This program is free software; you can redistribute it and/or modify    *
+ * it under the terms of the GNU General Public License as published by    *
+ * the Free Software Foundation; either version 2 of the License, or       *
+ * (at your option) any later version.                                     *
+ *                                                                         *
+ * This program is distributed in the hope that it will be useful,         *
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of          *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the           *
+ * GNU General Public License for more details.                            *
+ *                                                                         *
+ * You should have received a copy of the GNU General Public License       *
+ * along with this program; if not, write to the Free Software             *
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.               *
+ ***************************************************************************/
+
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/vmalloc.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/ioctl.h>
+#include <linux/delay.h>
+#include <linux/wrapper.h>
+#include <asm/page.h>
+#include <asm/uaccess.h>
+
+#include "w9968cf.h"
+#include "w9968cf_decoder.h"
+
+EXPORT_NO_SYMBOLS;
+
+
+
+/****************************************************************************
+ * Modules paramaters                                                       *
+ ****************************************************************************/
+
+static u8 vppmod_load = W9968CF_VPPMOD_LOAD;
+static u8 simcams = W9968CF_SIMCAMS;
+static int video_nr[]={[0 ... W9968CF_MAX_DEVICES-1] = -1}; /* -1=first free */
+static u16 packet_size[] = {[0 ... W9968CF_MAX_DEVICES-1]=W9968CF_PACKET_SIZE};
+static u8 max_buffers[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_BUFFERS};
+static u8 double_buffer[] = {[0 ... W9968CF_MAX_DEVICES-1] = 
+                             W9968CF_DOUBLE_BUFFER};
+static u8 clamping[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_CLAMPING};
+static u8 filter_type[]= {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_FILTER_TYPE};
+static u8 largeview[]= {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_LARGEVIEW};
+static u8 decompression[] = {[0 ... W9968CF_MAX_DEVICES-1] = 
+                             W9968CF_DECOMPRESSION};
+static u8 upscaling[]= {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_UPSCALING};
+static u8 force_palette[] = {[0 ... W9968CF_MAX_DEVICES-1] = 0};
+static u8 force_rgb[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_FORCE_RGB};
+static u8 autobright[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_AUTOBRIGHT};
+static u8 autoexp[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_AUTOEXP};
+static u8 lightfreq[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_LIGHTFREQ};
+static u8 bandingfilter[] = {[0 ... W9968CF_MAX_DEVICES-1]=
+                             W9968CF_BANDINGFILTER};
+static int clockdiv[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_CLOCKDIV};
+static u8 backlight[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_BACKLIGHT};
+static u8 mirror[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_MIRROR};
+static u8 sensor_mono[] = {[0 ... W9968CF_MAX_DEVICES-1]=W9968CF_SENSOR_MONO};
+static u16 brightness[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_BRIGHTNESS};
+static u16 hue[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_HUE};
+static u16 colour[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_COLOUR};
+static u16 contrast[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_CONTRAST};
+static u16 whiteness[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_WHITENESS};
+#ifdef W9968CF_DEBUG
+static u8 debug = W9968CF_DEBUG_LEVEL;
+static u8 specific_debug = W9968CF_SPECIFIC_DEBUG;
+#endif
+
+MODULE_AUTHOR("Luca Risolia <luca_ing@libero.it>");
+
+MODULE_DESCRIPTION("Video4Linux driver for "
+                   "W996[87]CF JPEG USB Dual Mode Camera Chip");
+
+MODULE_SUPPORTED_DEVICE("Video");
+
+MODULE_LICENSE("GPL");
+
+MODULE_PARM(vppmod_load, "i");
+MODULE_PARM(simcams, "i");
+MODULE_PARM(video_nr, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "i");
+MODULE_PARM(packet_size, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "i");
+MODULE_PARM(max_buffers, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "i");
+MODULE_PARM(double_buffer, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "i");
+MODULE_PARM(clamping, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "i");
+MODULE_PARM(filter_type, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "i");
+MODULE_PARM(largeview, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "i");
+MODULE_PARM(decompression, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "i");
+MODULE_PARM(upscaling, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "i");
+MODULE_PARM(force_palette, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "i");
+MODULE_PARM(force_rgb, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "i");
+MODULE_PARM(autobright, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "l");
+MODULE_PARM(autoexp, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "l");
+MODULE_PARM(lightfreq, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "l");
+MODULE_PARM(bandingfilter, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "l");
+MODULE_PARM(clockdiv, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "l");
+MODULE_PARM(backlight, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "l");
+MODULE_PARM(mirror, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "l");
+MODULE_PARM(sensor_mono, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "l");
+MODULE_PARM(brightness, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "l");
+MODULE_PARM(hue, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "l");
+MODULE_PARM(colour, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "l");
+MODULE_PARM(contrast, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "l");
+MODULE_PARM(whiteness, "0-" __MODULE_STRING(W9968CF_MAX_DEVICES) "l");
+#ifdef W9968CF_DEBUG
+MODULE_PARM(debug, "i");
+MODULE_PARM(specific_debug, "i");
+#endif
+
+MODULE_PARM_DESC(vppmod_load, 
+                 "\n<0|1> Automatic 'w9968cf-vpp' module loading."
+                 "\n0 disable, 1 enable."
+                 "\nIf enabled, every time an application attempts to open a"
+                 "\ncamera, 'insmod' searches for the video post-processing"
+                 "\nmodule in the system and loads it automatically (if"
+                 "\npresent). The 'w9968cf-vpp' module adds extra image"
+                 "\nmanipulation functions to the 'w9968cf' module, like"
+                 "\nsoftware up-scaling,colour conversions and video decoding."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_VPPMOD_LOAD)"."
+                 "\n");
+MODULE_PARM_DESC(simcams, 
+                 "\n<n> Number of cameras allowed to stream simultaneously."
+                 "\nn may vary from 0 to "
+                 __MODULE_STRING(W9968CF_MAX_DEVICES)"."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_SIMCAMS)"."
+                 "\n");
+MODULE_PARM_DESC(video_nr,
+                 "\n<-1|n[,...]> Specify V4L minor mode number."
+                 "\n -1 = use next available (default)"
+                 "\n  n = use minor number n (integer >= 0)"
+                 "\nYou can specify " __MODULE_STRING(W9968CF_MAX_DEVICES)
+                 " cameras this way."
+                 "\nFor example:"
+                 "\nvideo_nr=-1,2,-1 would assign minor number 2 to"
+                 "\nthe second camera and use auto for the first"
+                 "\none and for every other camera."
+                 "\n");
+MODULE_PARM_DESC(packet_size,
+                 "\n<n[,...]> Specify the maximum data payload"
+                 "\nsize in bytes for alternate settings, for each device."
+                 "\nn is scaled between 63 and 1023 "
+                 "(default is "__MODULE_STRING(W9968CF_PACKET_SIZE)")."
+                 "\n");
+MODULE_PARM_DESC(max_buffers,
+                 "\n<n[,...]> Only for advanced users."
+                 "\nSpecify the maximum number of video frame buffers"
+                 "\nto allocate for each device, from 2 to "
+                 __MODULE_STRING(W9968CF_MAX_BUFFERS)
+                 ". (default is "__MODULE_STRING(W9968CF_BUFFERS)")."
+                 "\n");
+MODULE_PARM_DESC(double_buffer, 
+                 "\n<0|1[,...]> "
+                 "Hardware double buffering: 0 disabled, 1 enabled."
+                 "\nIt should be enabled if you want smooth video output: if"
+                 "\nyou obtain out of sync. video, disable it at all, or try"
+                 "\nto decrease the 'clockdiv' module paramater value."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_DOUBLE_BUFFER)
+                 " for every device."
+                 "\n");
+MODULE_PARM_DESC(clamping, 
+                 "\n<0|1[,...]> Video data clamping: 0 disabled, 1 enabled."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_CLAMPING)
+                 " for every device."
+                 "\n");
+MODULE_PARM_DESC(filter_type, 
+                 "\n<0|1|2[,...]> Video filter type."
+                 "\n0 none, 1 (1-2-1) 3-tap filter, "
+                 "2 (2-3-6-3-2) 5-tap filter."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_FILTER_TYPE)
+                 " for every device."
+                 "\nThe filter is used to reduce noise and aliasing artifacts"
+                 "\nproduced by the CCD or CMOS sensor, and the scaling"
+                 " process."
+                 "\n");
+MODULE_PARM_DESC(largeview, 
+                 "\n<0|1[,...]> Large view: 0 disabled, 1 enabled."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_LARGEVIEW)
+                 " for every device."
+                 "\n");
+MODULE_PARM_DESC(upscaling, 
+                 "\n<0|1[,...]> Software scaling (for non-compressed video):"
+                 "\n0 disabled, 1 enabled."
+                 "\nDisable it if you have a slow CPU or you don't have"
+                 " enough memory."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_UPSCALING)
+                 " for every device."
+                 "\nIf 'w9968cf-vpp' is not loaded, this paramater is"
+                 " set to 0.");
+MODULE_PARM_DESC(decompression,
+                 "\n<0|1|2[,...]> Software video decompression:"
+                 "\n- 0 disables decompression (doesn't allow formats needing"
+                 " decompression)"
+                 "\n- 1 forces decompression (allows formats needing"
+                 " decompression only);"
+                 "\n- 2 allows any permitted formats."
+                 "\nFormats supporting compressed video are YUV422P and"
+                 " YUV420P/YUV420 "
+                 "\nin any resolutions where both width and height are "
+                 "a multiple of 16."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_DECOMPRESSION)
+                 " for every device."
+                 "\nIf 'w9968cf-vpp' is not loaded, forcing decompression is "
+                 "\nnot allowed; in this case this paramater is set to 2.");
+MODULE_PARM_DESC(force_palette,
+                 "\n<0"
+                 "|" __MODULE_STRING(VIDEO_PALETTE_UYVY)
+                 "|" __MODULE_STRING(VIDEO_PALETTE_YUV420)
+                 "|" __MODULE_STRING(VIDEO_PALETTE_YUV422P)
+                 "|" __MODULE_STRING(VIDEO_PALETTE_YUV420P)
+                 "|" __MODULE_STRING(VIDEO_PALETTE_YUYV)
+                 "|" __MODULE_STRING(VIDEO_PALETTE_YUV422)
+                 "|" __MODULE_STRING(VIDEO_PALETTE_GREY)
+                 "|" __MODULE_STRING(VIDEO_PALETTE_RGB555)
+                 "|" __MODULE_STRING(VIDEO_PALETTE_RGB565)
+                 "|" __MODULE_STRING(VIDEO_PALETTE_RGB24)
+                 "|" __MODULE_STRING(VIDEO_PALETTE_RGB32)
+                 "[,...]>"
+                 " Force picture palette."
+                 "\nIn order:"
+                 "\n- 0 allows any of the following formats:"
+                 "\n- UYVY    16 bpp - Original video, compression disabled"
+                 "\n- YUV420  12 bpp - Original video, compression enabled"
+                 "\n- YUV422P 16 bpp - Original video, compression enabled"
+                 "\n- YUV420P 12 bpp - Original video, compression enabled"
+                 "\n- YUVY    16 bpp - Software conversion from UYVY"
+                 "\n- YUV422  16 bpp - Software conversion from UYVY"
+                 "\n- GREY     8 bpp - Software conversion from UYVY"
+                 "\n- RGB555  16 bpp - Software conversion from UYVY"
+                 "\n- RGB565  16 bpp - Software conversion from UYVY"
+                 "\n- RGB24   24 bpp - Software conversion from UYVY"
+                 "\n- RGB32   32 bpp - Software conversion from UYVY"
+                 "\nWhen not 0, this paramater will override 'decompression'."
+                 "\nDefault value is 0 for every device."
+                 "\nInitial palette is "
+                 __MODULE_STRING(W9968CF_PALETTE_DECOMP_ON)"."
+                 "\nIf 'w9968cf-vpp' is not loaded, this paramater is"
+                 " set to 9 (UYVY).");
+MODULE_PARM_DESC(force_rgb, 
+                 "\n<0|1[,...]> Read RGB video data instead of BGR:"
+                 "\n 1 = use RGB component ordering."
+                 "\n 0 = use BGR component ordering."
+                 "\nThis parameter has effect when using RGBX palettes only."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_FORCE_RGB)
+                 " for every device."
+                 "\n");
+MODULE_PARM_DESC(autobright,
+                 "\n<0|1[,...]> CMOS sensor automatically changes brightness:"
+                 "\n 0 = no, 1 = yes"
+                 "\nDefault value is "__MODULE_STRING(W9968CF_AUTOBRIGHT)
+                 " for every device."
+                 "\n");
+MODULE_PARM_DESC(autoexp,
+                 "\n<0|1[,...]> CMOS sensor automatically changes exposure:"
+                 "\n 0 = no, 1 = yes"
+                 "\nDefault value is "__MODULE_STRING(W9968CF_AUTOEXP)
+                 " for every device."
+                 "\n");
+MODULE_PARM_DESC(lightfreq,
+                 "\n<50|60[,...]> Light frequency in Hz:"
+                 "\n 50 for European and Asian lighting,"
+                 " 60 for American lighting."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_LIGHTFREQ)
+                 " for every device."
+                 "\n");
+MODULE_PARM_DESC(bandingfilter,
+                 "\n<0|1[,...]> Banding filter to reduce effects of"
+                 " fluorescent lighting:"
+                 "\n 0 disabled, 1 enabled."
+                 "\nThis filter tries to reduce the pattern of horizontal"
+                 "\nlight/dark bands caused by some (usually fluorescent)"
+                 " lighting."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_BANDINGFILTER)
+                 " for every device."
+                 "\n");
+MODULE_PARM_DESC(clockdiv,
+                 "\n<-1|n[,...]> "
+                 "Force pixel clock divisor to a specific value (for experts):"
+                 "\n  n may vary from 0 to 127."
+                 "\n -1 for automatic value."
+                 "\nSee also the 'double_buffer' module paramater."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_CLOCKDIV)
+                 " for every device."
+                 "\n");
+MODULE_PARM_DESC(backlight,
+                 "\n<0|1[,...]> Objects are lit from behind:"
+                 "\n 0 = no, 1 = yes"
+                 "\nDefault value is "__MODULE_STRING(W9968CF_BACKLIGHT)
+                 " for every device."
+                 "\n");
+MODULE_PARM_DESC(mirror,
+                 "\n<0|1[,...]> Reverse image horizontally:"
+                 "\n 0 = no, 1 = yes"
+                 "\nDefault value is "__MODULE_STRING(W9968CF_MIRROR)
+                 " for every device."
+                 "\n");
+MODULE_PARM_DESC(sensor_mono,
+                 "\n<0|1[,...]> The OV CMOS sensor is monochrome:"
+                 "\n 0 = no, 1 = yes"
+                 "\nDefault value is "__MODULE_STRING(W9968CF_SENSOR_MONO)
+                 " for every device."
+                 "\n");
+MODULE_PARM_DESC(brightness, 
+                 "\n<n[,...]> Set picture brightness (0-65535)."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_BRIGHTNESS)
+                 " for every device."
+                 "\nThis parameter has no effect if 'autobright' is enabled."
+                 "\n");
+MODULE_PARM_DESC(hue, 
+                 "\n<n[,...]> Set picture hue (0-65535)."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_HUE)
+                 " for every device."
+                 "\n");
+MODULE_PARM_DESC(colour, 
+                 "\n<n[,...]> Set picture saturation (0-65535)."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_COLOUR)
+                 " for every device."
+                 "\n");
+MODULE_PARM_DESC(contrast, 
+                 "\n<n[,...]> Set picture contrast (0-65535)."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_CONTRAST)
+                 " for every device."
+                 "\n");
+MODULE_PARM_DESC(whiteness, 
+                 "\n<n[,...]> Set picture whiteness (0-65535)."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_WHITENESS)
+                 " for every device."
+                 "\n");
+#ifdef W9968CF_DEBUG
+MODULE_PARM_DESC(debug,
+                 "\n<n> Debugging information level, from 0 to 6:"
+                 "\n0 = none (be cautious)"
+                 "\n1 = critical errors"
+                 "\n2 = significant informations"
+                 "\n3 = configuration or general messages"
+                 "\n4 = warnings"
+                 "\n5 = called functions"
+                 "\n6 = function internals"
+                 "\nLevel 5 and 6 are useful for testing only, when just "
+                 "one device is used."
+                 "\nDefault value is "__MODULE_STRING(W9968CF_DEBUG_LEVEL)"."
+                 "\n");
+MODULE_PARM_DESC(specific_debug,
+                 "\n<0|1> Enable or disable specific debugging messages:"
+                 "\n0 = print messages concerning every level"
+                 " <= 'debug' level."
+                 "\n1 = print messages concerning the level"
+                 " indicated by 'debug'."
+                 "\nDefault value is "
+                 __MODULE_STRING(W9968CF_SPECIFIC_DEBUG)"."
+                 "\n");
+#endif /* W9968CF_DEBUG */
+
+
+
+/****************************************************************************
+ * Some prototypes                                                          *
+ ****************************************************************************/
+
+/* Video4linux interface */
+static struct file_operations w9968cf_fops;
+static int w9968cf_open(struct inode*, struct file*);
+static int w9968cf_release(struct inode*, struct file*);
+static ssize_t w9968cf_read(struct file*, char*, size_t, loff_t*);
+static int w9968cf_mmap(struct file*, struct vm_area_struct*);
+static int w9968cf_ioctl(struct inode*, struct file*,
+                         unsigned int, unsigned long);
+static int w9968cf_do_ioctl(struct w9968cf_device*, unsigned int, void*);
+
+/* /proc interface */
+#if defined(CONFIG_VIDEO_PROC_FS)
+static void w9968cf_proc_create(void);
+static void w9968cf_proc_destroy(void);
+static void w9968cf_proc_create_dev(struct w9968cf_device*);
+static void w9968cf_proc_destroy_dev(struct w9968cf_device*);
+static int w9968cf_proc_read_global(char*, char**, off_t, int, int*, void*);
+static int w9968cf_proc_read_dev(char*, char**, off_t, int, int*, void*);
+#else
+static inline void w9968cf_proc_create(void) {}
+static inline void w9968cf_proc_destroy(void) {}
+static inline void w9968cf_proc_create_dev(struct w9968cf_device* cam) {}
+static inline void w9968cf_proc_destroy_dev(struct w9968cf_device* cam) {}
+#endif
+
+/* USB-specific */
+static void w9968cf_urb_complete(struct urb *urb);
+static int w9968cf_start_transfer(struct w9968cf_device*);
+static int w9968cf_stop_transfer(struct w9968cf_device*);
+static int w9968cf_write_reg(struct w9968cf_device*, u16 value, u16 index);
+static int w9968cf_read_reg(struct w9968cf_device*, u16 index);
+static int w9968cf_write_fsb(struct w9968cf_device*, u16* data);
+static int w9968cf_write_sb(struct w9968cf_device*, u16 value);
+static int w9968cf_read_sb(struct w9968cf_device*);
+static int w9968cf_upload_quantizationtables(struct w9968cf_device*);
+
+
+/* Low-level I2C (SMBus) I/O */
+static int w9968cf_smbus_start(struct w9968cf_device*);
+static int w9968cf_smbus_stop(struct w9968cf_device*);
+static int w9968cf_smbus_write_byte(struct w9968cf_device*, u8 v);
+static int w9968cf_smbus_read_byte(struct w9968cf_device*, u8* v);
+static int w9968cf_smbus_write_ack(struct w9968cf_device*);
+static int w9968cf_smbus_read_ack(struct w9968cf_device*);
+static int w9968cf_i2c_adap_read_byte(struct w9968cf_device* cam,
+                                      u16 address, u8* value);
+static int w9968cf_i2c_adap_read_byte_data(struct w9968cf_device*, u16 address, 
+                                           u8 subaddress, u8* value);
+static int w9968cf_i2c_adap_write_byte(struct w9968cf_device*,
+                                       u16 address, u8 subaddress);
+static int w9968cf_i2c_adap_fastwrite_byte_data(struct w9968cf_device*,
+                                                u16 address, u8 subaddress,
+                                                u8 value);
+
+/* I2C interface to kernel */
+static int w9968cf_i2c_init(struct w9968cf_device*);
+static int w9968cf_i2c_smbus_xfer(struct i2c_adapter*, u16 addr, 
+                                  unsigned short flags, char read_write, 
+                                  u8 command, int size, union i2c_smbus_data*);
+static u32 w9968cf_i2c_func(struct i2c_adapter*);
+static int w9968cf_i2c_attach_inform(struct i2c_client*);
+static int w9968cf_i2c_detach_inform(struct i2c_client*);
+static int w9968cf_i2c_control(struct i2c_adapter*, unsigned int cmd,
+                               unsigned long arg);
+static void w9968cf_i2c_inc_use(struct i2c_adapter*);
+static void w9968cf_i2c_dec_use(struct i2c_adapter*);
+
+/* Memory management */
+static inline unsigned long kvirt_to_pa(unsigned long adr);
+static void* rvmalloc(unsigned long size);
+static void rvfree(void *mem, unsigned long size);
+static void w9968cf_deallocate_memory(struct w9968cf_device*);
+static int  w9968cf_allocate_memory(struct w9968cf_device*);
+static inline unsigned long w9968cf_get_max_bufsize(struct w9968cf_device*);
+
+/* High-level CMOS sensor control functions */
+static int w9968cf_sensor_set_control(struct w9968cf_device*,int cid,int val);
+static int w9968cf_sensor_get_control(struct w9968cf_device*,int cid,int *val);
+static inline int w9968cf_sensor_cmd(struct w9968cf_device*, 
+                                     unsigned int cmd, void *arg);
+static void w9968cf_sensor_configure(struct w9968cf_device*);
+static int w9968cf_sensor_change_settings(struct w9968cf_device*);
+static int w9968cf_sensor_get_picture(struct w9968cf_device*, 
+                                      struct video_picture*);
+static int w9968cf_sensor_set_picture(struct w9968cf_device*, 
+                                      struct video_picture pict);
+
+/* Other helper functions */
+static void w9968cf_configure_camera(struct w9968cf_device*,struct usb_device*,
+                                     enum w9968cf_model_id, 
+                                     const unsigned short dev_nr);
+static int w9968cf_turn_on_led(struct w9968cf_device*);
+static int w9968cf_init_chip(struct w9968cf_device*);
+static int w9968cf_set_picture(struct w9968cf_device*, struct video_picture);
+static int w9968cf_set_window(struct w9968cf_device*, struct video_window);
+static inline u16 w9968cf_valid_palette(u16 palette);
+static inline u16 w9968cf_valid_depth(u16 palette);
+static inline u8 w9968cf_need_decompression(u16 palette);
+static int w9968cf_postprocess_frame(struct w9968cf_device*, 
+                                     struct w9968cf_frame_t*);
+static int w9968cf_adjust_window_size(struct w9968cf_device*, u16* w, u16* h);
+static void w9968cf_init_framelist(struct w9968cf_device*);
+static void w9968cf_push_frame(struct w9968cf_device*, u8 f_num);
+static void w9968cf_pop_frame(struct w9968cf_device*,struct w9968cf_frame_t**);
+static void w9968cf_release_resources(struct w9968cf_device*);
+
+/* Intermodule communication */
+static int w9968cf_vppmod_detect(void);
+static void w9968cf_vppmod_release(void);
+
+/* Pointers to registered video post-processing functions */
+static void (*w9968cf_vpp_init_decoder)(void);
+static int (*w9968cf_vpp_check_headers)(const unsigned char*,
+                                        const unsigned long);
+static int (*w9968cf_vpp_decode)(const char*, const unsigned, 
+                                 const unsigned, const unsigned, char*);
+static void (*w9968cf_vpp_swap_yuvbytes)(void*, unsigned long);
+static void (*w9968cf_vpp_uyvy_to_rgbx)(u8*, unsigned long, u8*, u16, u8);
+static void (*w9968cf_vpp_scale_up)(u8*, u8*, u16, u16, u16, u16, u16);
+
+
+
+/****************************************************************************
+ * Symbolic names                                                           *
+ ****************************************************************************/
+
+/* Used to represent a list of values and their respective symbolic names */
+struct w9968cf_symbolic_list {
+	const int num;
+	const char *name;
+};
+
+/*-------------------------------------------------------------------------- 
+  Returns the name of the matching element in the symbolic_list array. The
+  end of the list must be marked with an element that has a NULL name.
+  --------------------------------------------------------------------------*/
+static inline const char * 
+symbolic(struct w9968cf_symbolic_list list[], const int num)
+{
+	int i;
+
+	for (i = 0; list[i].name != NULL; i++)
+		if (list[i].num == num)
+			return (list[i].name);
+
+	return "Unknown";
+}
+
+static struct w9968cf_symbolic_list camlist[] = {
+	{ W9968CF_MOD_GENERIC, "W996[87]CF JPEG USB Dual Mode Camera" },
+	{ W9968CF_MOD_CLVBWGP, "Creative Labs Video Blaster WebCam Go Plus" },
+
+	/* Other cameras (having the same descriptors as Generic W996[87]CF) */
+	{ W9968CF_MOD_ADPA5R, "Aroma Digi Pen ADG-5000 Refurbished" },
+	{ W9986CF_MOD_AU, "AVerTV USB" },
+	{ W9968CF_MOD_CLVBWG, "Creative Labs Video Blaster WebCam Go" },
+	{ W9968CF_MOD_DLLDK, "Die Lebon LDC-D35A Digital Kamera" },
+	{ W9968CF_MOD_EEEMC, "Ezonics EZ-802 EZMega Cam" },
+	{ W9968CF_MOD_ODPVDMPC, "OPCOM Digi Pen VGA Dual Mode Pen Camera" },
+
+	{  -1, NULL }
+};
+
+static struct w9968cf_symbolic_list senlist[] = {
+	{ CC_OV76BE,   "OV76BE" },
+	{ CC_OV7610,   "OV7610" },
+	{ CC_OV7620,   "OV7620" },
+	{ CC_OV7620AE, "OV7620AE" },
+	{ CC_OV6620,   "OV6620" },
+	{ CC_OV6630,   "OV6630" },
+	{ CC_OV6630AE, "OV6630AE" },
+	{ CC_OV6630AF, "OV6630AF" },
+	{ -1, NULL }
+};
+
+/* Video4Linux1 palettes */
+static struct w9968cf_symbolic_list v4l1_plist[] = {
+	{ VIDEO_PALETTE_GREY,    "GREY" },
+	{ VIDEO_PALETTE_HI240,   "HI240" },
+	{ VIDEO_PALETTE_RGB565,  "RGB565" },
+	{ VIDEO_PALETTE_RGB24,   "RGB24" },
+	{ VIDEO_PALETTE_RGB32,   "RGB32" },
+	{ VIDEO_PALETTE_RGB555,  "RGB555" },
+	{ VIDEO_PALETTE_YUV422,  "YUV422" },
+	{ VIDEO_PALETTE_YUYV,    "YUYV" },
+	{ VIDEO_PALETTE_UYVY,    "UYVY" },
+	{ VIDEO_PALETTE_YUV420,  "YUV420" },
+	{ VIDEO_PALETTE_YUV411,  "YUV411" },
+	{ VIDEO_PALETTE_RAW,     "RAW" },
+	{ VIDEO_PALETTE_YUV422P, "YUV422P" },
+	{ VIDEO_PALETTE_YUV411P, "YUV411P" },
+	{ VIDEO_PALETTE_YUV420P, "YUV420P" },
+	{ VIDEO_PALETTE_YUV410P, "YUV410P" },
+	{ -1, NULL }
+};
+
+/* Decoder error codes: */
+static struct w9968cf_symbolic_list decoder_errlist[] = {
+	{ W9968CF_DEC_ERR_CORRUPTED_DATA, "Corrupted data" },
+	{ W9968CF_DEC_ERR_BUF_OVERFLOW,   "Buffer overflow" },
+	{ W9968CF_DEC_ERR_NO_SOI,         "SOI marker not found" },     
+	{ W9968CF_DEC_ERR_NO_SOF0,        "SOF0 marker not found" },
+	{ W9968CF_DEC_ERR_NO_SOS,         "SOS marker not found" },
+	{ W9968CF_DEC_ERR_NO_EOI,         "EOI marker not found" },
+	{ -1, NULL }
+};
+
+/* URB error codes: */
+static struct w9968cf_symbolic_list urb_errlist[] = {
+	{ -ENOMEM,    "No memory for allocation of internal structures" },
+	{ -ENOSPC,    "The host controller's bandwidth is already consumed" },
+	{ -ENOENT,    "URB was canceled by unlink_urb" },
+	{ -EXDEV,     "ISO transfer only partially completed" },
+	{ -EAGAIN,    "Too match scheduled for the future" },
+	{ -ENXIO,     "URB already queued" },
+	{ -EFBIG,     "Too much ISO frames requested" },
+	{ -ENOSR,     "Buffer error (overrun)" },
+	{ -EPIPE,     "Specified endpoint is stalled (device not responding)"},
+	{ -EOVERFLOW, "Babble (bad cable?)" },
+	{ -EPROTO,    "Bit-stuff error (bad cable?)" },
+	{ -EILSEQ,    "CRC/Timeout" },
+	{ -ETIMEDOUT, "NAK (device does not respond)" },
+	{ -1, NULL }
+};
+
+
+
+/****************************************************************************
+ * Memory management functions                                              *
+ ****************************************************************************/
+
+/* Shameless copy from bttv-driver.c */
+
+/* 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)
+		return NULL;
+
+	memset(mem, 0, size); /* Clear the ram out, no junk to the user */
+	adr = (unsigned long) mem;
+	while (size > 0) {
+		mem_map_reserve(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)
+		return;
+
+	adr = (unsigned long) mem;
+	while ((long) size > 0) {
+		mem_map_unreserve(vmalloc_to_page((void *)adr));
+		adr += PAGE_SIZE;
+		size -= PAGE_SIZE;
+	}
+	vfree(mem);
+}
+/* End of shameless copy */
+
+
+/*--------------------------------------------------------------------------
+  Return the maximum size (in bytes) of a frame buffer.
+  --------------------------------------------------------------------------*/
+static inline unsigned long w9968cf_get_max_bufsize(struct w9968cf_device* cam)
+{
+	u8 bpp = (w9968cf_vppmod_present) ? 4 : 2;
+	return (cam->upscaling) ? W9968CF_MAX_WIDTH*W9968CF_MAX_HEIGHT*bpp :
+	                          cam->maxwidth*cam->maxheight*bpp;
+}
+
+
+/*--------------------------------------------------------------------------
+  Deallocate previously allocated memory.
+  --------------------------------------------------------------------------*/
+static void w9968cf_deallocate_memory(struct w9968cf_device* cam)
+{
+	u8 i;
+
+	/* Free the isochronous transfer buffers */
+	for (i = 0; i < W9968CF_URBS; i++) {
+		kfree(cam->transfer_buffer[i]);
+		cam->transfer_buffer[i] = NULL;
+	}
+
+	/* Free temporary frame buffer */
+	if (cam->frame_tmp.buffer) {
+		rvfree(cam->frame_tmp.buffer, W9968CF_HW_BUF_SIZE);
+		cam->frame_tmp.buffer = NULL;
+	}
+
+	/* Free helper buffer */
+	if (cam->vpp_buffer) {
+		rvfree(cam->vpp_buffer, w9968cf_get_max_bufsize(cam));
+		cam->vpp_buffer = NULL;
+	}
+	
+	/* Free video frame buffers */
+	if (cam->frame[0].buffer) {
+		rvfree(cam->frame[0].buffer, 
+		       cam->nbuffers * w9968cf_get_max_bufsize(cam));
+		cam->frame[0].buffer = NULL;
+	}
+
+	cam->nbuffers = 0;
+
+	DBG(5, "Memory successfully deallocated.")
+}
+
+
+/*--------------------------------------------------------------------------
+  Allocate memory buffers for USB transfers and video frames.
+  This function is called by open() only.
+  Return 0 on success, a negative number otherwise.
+  --------------------------------------------------------------------------*/
+static int w9968cf_allocate_memory(struct w9968cf_device* cam)
+{
+	const unsigned long bufsize = w9968cf_get_max_bufsize(cam);
+	const u16 p_size = wMaxPacketSize[cam->altsetting-1];
+	void* buff = NULL;
+	u8 i;
+
+	/* NOTE: Deallocation is done elsewhere in case of error */
+
+	/* Allocate memory for the isochronous transfer buffers */
+	for (i = 0; i < W9968CF_URBS; i++) {
+		if (!(cam->transfer_buffer[i] =
+		      kmalloc(W9968CF_ISO_PACKETS*p_size, GFP_KERNEL))) {
+			DBG(1, "Couldn't allocate memory for the isochronous "
+			       "transfer buffers (%d bytes).", 
+			    p_size * W9968CF_ISO_PACKETS)
+			return -ENOMEM;
+		}
+		memset(cam->transfer_buffer[i], 0, W9968CF_ISO_PACKETS*p_size);
+	}
+
+	/* Allocate memory for the temporary frame buffer */
+	if (!(cam->frame_tmp.buffer = rvmalloc(W9968CF_HW_BUF_SIZE))) {
+		DBG(1, "Couldn't allocate memory for the temporary "
+		       "video frame buffer (%i bytes).", W9968CF_HW_BUF_SIZE)
+		return -ENOMEM;
+	}
+
+	/* Allocate memory for the helper buffer */
+	if (w9968cf_vppmod_present) {
+		if (!(cam->vpp_buffer = rvmalloc(bufsize))) {
+			DBG(1, "Couldn't allocate memory for the helper buffer"
+			       " (%li bytes).", bufsize)
+			return -ENOMEM;
+		}
+	} else
+		cam->vpp_buffer = NULL;
+
+	/* Allocate memory for video frame buffers */	
+	cam->nbuffers = cam->max_buffers;
+	while (cam->nbuffers >= 2) {
+		if ((buff = rvmalloc(cam->nbuffers * bufsize)))
+			break;
+		else
+			cam->nbuffers--;
+	}
+
+	if (!buff) {
+		DBG(1, "Couldn't allocate memory for the video frame buffers.")
+		cam->nbuffers = 0;
+		return -ENOMEM;
+	}
+
+	if (cam->nbuffers != cam->max_buffers)
+		DBG(2, "Couldn't allocate memory for %d video frame buffers. "
+		       "Only memory for %d buffers has been allocated.",
+		    cam->max_buffers, cam->nbuffers)
+
+	for (i = 0; i < cam->nbuffers; i++) {
+		cam->frame[i].buffer = buff + i*bufsize;
+		/* Circular list */
+		if (i != cam->nbuffers-1)
+			cam->frame[i].next = &cam->frame[i+1];
+		else
+			cam->frame[i].next = &cam->frame[0];
+		cam->frame[i].status = F_UNUSED;
+	}
+
+	DBG(5, "Memory successfully allocated.")
+	return 0;
+}
+
+
+
+/****************************************************************************
+ * /proc interface                                                          *
+ ****************************************************************************/
+
+#if defined(CONFIG_VIDEO_PROC_FS)
+
+static struct proc_dir_entry* w9968cf_proc_entry, * w9968cf_proc_entry_global;
+extern struct proc_dir_entry* video_proc_entry;
+
+#define YES_NO(x) ((x) ? "yes" : "no")
+
+/*--------------------------------------------------------------------------
+  Read /proc/video/w9968cf/global 
+  --------------------------------------------------------------------------*/
+static int 
+w9968cf_proc_read_global(char* page, char** start, off_t offset,
+                         int count, int* eof, void* data)
+{
+	struct list_head *list = (struct list_head*)data, *ptr;
+	struct w9968cf_device* cam;
+	char* out = page;
+	int len;
+	u8 ncams = 0;
+
+	if (down_interruptible(&w9968cf_devlist_sem))
+		return -ERESTARTSYS;
+
+	/* How many connected cameras ? */
+	list_for_each(ptr, list)
+		ncams++;
+
+	out += sprintf(out,"driver_name       : %s\n", W9968CF_MODULE_NAME);
+	out += sprintf(out,"driver_version    : %s\n", W9968CF_MODULE_VERSION);
+	out += sprintf(out,"driver_author     : %s\n", W9968CF_MODULE_AUTHOR);
+	out += sprintf(out,"author_email      : %s\n", W9968CF_AUTHOR_EMAIL);
+	out += sprintf(out,"vpp_w9968cf_module: %s\n",
+	               w9968cf_vppmod_present ? "detected" : "not detected");
+	out += sprintf(out,"max_allowed_cams  : %d\n", simcams);
+	out += sprintf(out,"registered_cameras: %d\n", ncams);
+
+	list_for_each(ptr, list) {
+		cam = list_entry(ptr, struct w9968cf_device, v4llist);
+		out += sprintf(out,"/dev/video%d       : %s\n", 
+		               cam->v4ldev.minor, symbolic(camlist, cam->id));
+	}
+
+	up(&w9968cf_devlist_sem);
+
+	len = out - page;
+	len -= offset;
+	if (len < count) {
+		*eof = 1;
+		if (len <= 0)
+			return 0;
+	} else
+		len = count;
+
+	*start = page + offset;
+
+	return len;
+}
+
+
+/*--------------------------------------------------------------------------
+  Read /proc/video/w9968cf/dev<minor#>
+  --------------------------------------------------------------------------*/
+static int 
+w9968cf_proc_read_dev(char* page, char** start, off_t offset,
+                      int count, int* eof, void* data)
+{
+	struct w9968cf_device* cam = (struct w9968cf_device* )data;
+	int len;
+	char* out = page;
+
+	static struct video_picture pict; /* it has to be static */
+	static int rc = 0;
+
+	if (down_interruptible(&cam->procfs_sem))
+		return -ERESTARTSYS;
+
+	if (offset == 0)
+		rc = w9968cf_sensor_get_picture(cam, &pict);
+
+	out += sprintf(out,"camera_model      : %s\n",
+	               symbolic(camlist, cam->id));
+	out += sprintf(out,"sensor_model      : %s\n",
+	               symbolic(senlist, cam->sensor));
+	out += sprintf(out,"sensor_monochrome : %s\n",
+	               YES_NO(cam->sensor_mono));
+	if (cam->users)
+		out += sprintf(out,"user_program      : %s\n",cam->command);
+	out += sprintf(out,"packet_size_bytes : %d\n", 
+	               wMaxPacketSize[cam->altsetting-1]);
+	out += sprintf(out,"allocated_buffers : %d\n",cam->nbuffers);
+	out += sprintf(out,"streaming         : %s\n",YES_NO(cam->streaming));
+	out += sprintf(out,"compression       : %s\n",
+	               YES_NO(cam->vpp_flag & VPP_DECOMPRESSION));
+	out += sprintf(out,"uyvy_to_rgbx      : %s\n",
+	               YES_NO(cam->vpp_flag & VPP_UYVY_TO_RGBX));
+	out += sprintf(out,"uv-y_reordering   : %s\n", 
+	               YES_NO(cam->vpp_flag & VPP_SWAP_YUV_BYTES));
+	out += sprintf(out,"software_upscaling: %s\n",
+	               YES_NO(cam->vpp_flag & VPP_UPSCALE));
+	out += sprintf(out,"clock_divisor     : %d\n",cam->clockdiv);
+	out += sprintf(out,"palette           : %s\n", 
+	               symbolic(v4l1_plist, cam->picture.palette));
+	out += sprintf(out,"depth_bpp         : %d\n",cam->picture.depth);
+	out += sprintf(out,"x_window_offset   : %d\n",cam->window.x);
+	out += sprintf(out,"y_window_offset   : %d\n",cam->window.y);	
+	out += sprintf(out,"width             : %d\n",cam->window.width);
+	out += sprintf(out,"height            : %d\n",cam->window.height);
+	out += sprintf(out,"max_buffers       : %d\n",cam->max_buffers);
+	out += sprintf(out,"decompression     : %s\n",
+	               (!cam->decompression)? "off" :
+	               ((cam->decompression == 1) ? "force" : "on"));
+	out += sprintf(out,"force_rgb         : %s\n",YES_NO(cam->force_rgb));
+	out += sprintf(out,"video_clamping    : %s\n",YES_NO(cam->clamping));
+	out += sprintf(out,"hw_double_buffer  : %s\n",
+	               YES_NO(cam->double_buffer));
+	out += sprintf(out,"filter_type       : %s\n",
+	               (!cam->filter_type) ? "none" : 
+	               ((cam->filter_type == 1) ? "3-tap" : "5-tap"));
+	out += sprintf(out,"large_view        : %s\n",YES_NO(cam->largeview));
+	out += sprintf(out,"auto_brightness   : %s\n",YES_NO(cam->auto_brt));
+	out += sprintf(out,"auto_exposure     : %s\n",YES_NO(cam->auto_exp));
+	out += sprintf(out,"light_frequency   : %d\n",cam->lightfreq);
+	out += sprintf(out,"banding_filter    : %s\n",YES_NO(cam->bandfilt));
+	out += sprintf(out,"back_light        : %s\n",YES_NO(cam->backlight));
+	out += sprintf(out,"mirror            : %s\n",YES_NO(cam->mirror));
+	if (!rc) {
+		out += sprintf(out,"brightness        : %d\n",pict.brightness);
+		out += sprintf(out,"colour            : %d\n",pict.colour);
+		out += sprintf(out,"contrast          : %d\n",pict.contrast);
+		out += sprintf(out,"hue               : %d\n",pict.hue);
+		out += sprintf(out,"whiteness         : %d\n",pict.whiteness);
+	}
+	out += sprintf(out,"hs_polarity       : %d\n",cam->hs_polarity);
+	out += sprintf(out,"vs_polarity       : %d\n",cam->vs_polarity);
+#ifdef W9968CF_DEBUG
+	out += sprintf(out,"debug_level       : %d\n",debug);
+	out += sprintf(out,"specific_debug    : %s\n",YES_NO(specific_debug));
+#endif
+
+	len = out - page;
+	len -= offset;
+	if (len < count) {
+		*eof = 1;
+		if (len <= 0) {
+			up(&cam->procfs_sem);
+			return 0;
+		}
+	} else
+		len = count;
+
+	*start = page + offset;
+
+	up(&cam->procfs_sem);
+	return len;
+}
+
+
+static void w9968cf_proc_create_dev(struct w9968cf_device* cam)
+{
+	char name[5];
+
+	if (!w9968cf_proc_entry)
+		return;
+
+	/* Create per-device readable entry */
+	sprintf(name, "dev%d", cam->v4ldev.minor);
+	cam->proc_dev = create_proc_read_entry(name, S_IFREG|S_IRUGO|S_IWUSR, 
+	                                       w9968cf_proc_entry,
+	                                       w9968cf_proc_read_dev,
+	                                       (void*)cam);
+	if (!cam->proc_dev)
+		return;
+	cam->proc_dev->owner = THIS_MODULE;
+}
+
+
+static void w9968cf_proc_destroy_dev(struct w9968cf_device* cam)
+{
+	char name[5];
+
+	if (!cam->proc_dev)
+		return;
+
+	sprintf(name, "dev%d", cam->v4ldev.minor);
+
+	/* Destroy per-device entry */
+	remove_proc_entry(name, w9968cf_proc_entry);
+}
+
+
+static void w9968cf_proc_create(void)
+{
+	if (!video_proc_entry) {
+		DBG(2, "Error: /proc/video/ does not exist.")
+		return;
+	}
+
+	w9968cf_proc_entry = create_proc_entry("w9968cf", S_IFDIR,
+	                                       video_proc_entry);
+	if (!w9968cf_proc_entry) {
+		DBG(2, "Unable to create /proc/video/w9968cf/")
+		return;
+	}
+	w9968cf_proc_entry->owner = THIS_MODULE;
+
+	w9968cf_proc_entry_global = create_proc_read_entry("global", 
+	                                             S_IFREG|S_IRUGO|S_IWUSR,
+	                                             w9968cf_proc_entry,
+	                                             w9968cf_proc_read_global, 
+	                                             (void*)&w9968cf_dev_list);
+	if (w9968cf_proc_entry_global)
+		w9968cf_proc_entry_global->owner = THIS_MODULE;
+	else
+		DBG(2, "Unable to create /proc/video/w9968cf/global")
+
+	DBG(5, "/proc entries successfully created.")
+}
+
+
+static void w9968cf_proc_destroy(void)
+{
+	if (!w9968cf_proc_entry)
+		return;
+
+	if (w9968cf_proc_entry_global)
+		remove_proc_entry("global", w9968cf_proc_entry);
+
+	remove_proc_entry("w9968cf", video_proc_entry);
+
+	DBG(5, "/proc entries removed.")
+}
+
+#endif /* CONFIG_VIDEO_PROC_FS */
+
+
+
+/****************************************************************************
+ * USB-specific functions                                                   *
+ ****************************************************************************/
+
+/*--------------------------------------------------------------------------
+  This is an handler function which is called after the URBs are completed.
+  It collects multiple data packets coming from the camera by putting them
+  into frame buffers: one or more zero data length data packets are used to
+  mark the end of a video frame; the first non-zero data packet is the start
+  of the next video frame; if an error is encountered in a packet, the entire
+  video frame is discarded and grabbed again.
+  If there are no requested frames in the FIFO list, packets are collected into
+  a temporary buffer. 
+  --------------------------------------------------------------------------*/
+static void w9968cf_urb_complete(struct urb *urb)
+{
+	struct w9968cf_device* cam = (struct w9968cf_device*)urb->context;
+	struct w9968cf_frame_t** f;
+	unsigned long maxbufsize;
+	unsigned int len, status;
+	void* pos;
+	u8 i;
+	int err = 0;
+
+	if ((!cam->streaming) || cam->disconnected) {
+		DBG(4, "Got interrupt, but not streaming.")
+		return;
+	}
+
+	maxbufsize = min( (unsigned long)W9968CF_HW_BUF_SIZE, 
+	                  w9968cf_get_max_bufsize(cam) );
+
+	/* "(*f)" will be used instead of "cam->frame_current" */
+	f = &cam->frame_current;
+
+	/* If a frame has been requested and we are grabbing into  
+	   the temporary frame, we'll switch to that requested frame */
+	if ((*f) == &cam->frame_tmp && *cam->requested_frame) {
+		if (cam->frame_tmp.status == F_GRABBING) {
+			w9968cf_pop_frame(cam, &cam->frame_current);
+			(*f)->status = F_GRABBING;
+			(*f)->length = cam->frame_tmp.length;
+			memcpy((*f)->buffer, cam->frame_tmp.buffer,
+			       (*f)->length);
+			DBG(6, "Switched from temp. frame to frame #%d", 
+			    (*f) - &cam->frame[0])
+		}
+	}
+
+	for (i = 0; i < urb->number_of_packets; i++) {
+		len    = urb->iso_frame_desc[i].actual_length;
+		status = urb->iso_frame_desc[i].status;
+		pos    = urb->iso_frame_desc[i].offset + urb->transfer_buffer;
+
+		if (status && len != 0) {
+			DBG(4, "URB failed, error in data packet "
+			       "(error #%d, %s).",
+			    status, symbolic(urb_errlist, status))
+			(*f)->status = F_ERROR;
+			continue;
+		}
+
+		if (len) { /* start of frame */
+
+			if ((*f)->status == F_UNUSED) {
+				(*f)->status = F_GRABBING;
+				(*f)->length = 0;
+			}
+
+			/* Buffer overflows shouldn't happen, however...*/
+			if ((*f)->length + len > maxbufsize) {
+				DBG(4, "Buffer overflow: bad data packets.")
+				(*f)->status = F_ERROR;
+			}
+
+			if ((*f)->status == F_GRABBING) {
+				memcpy((*f)->buffer + (*f)->length, pos, len);
+				(*f)->length += len;
+			}
+
+		} else if ((*f)->status == F_GRABBING) { /* end of frame */
+
+			DBG(6, "Frame #%d successfully grabbed.",
+			    ((*f)==&cam->frame_tmp ? -1 : (*f)-&cam->frame[0]))
+
+			if (cam->vpp_flag & VPP_DECOMPRESSION) {
+				err=(*w9968cf_vpp_check_headers)((*f)->buffer,
+				                                 (*f)->length);
+				if (err) {
+					DBG(4, "Skip corrupted frame: %s",
+					    symbolic(decoder_errlist, err))
+					(*f)->status = F_UNUSED;
+					continue; /* grab this frame again */
+				}
+			}
+
+			(*f)->status = F_READY;
+			(*f)->queued = 0;
+
+			/* Take a pointer to the new frame from the FIFO list.
+			   If the list is empty,we'll use the temporary frame*/
+			if (*cam->requested_frame)
+				w9968cf_pop_frame(cam, &cam->frame_current);
+			else {
+				cam->frame_current = &cam->frame_tmp;
+				(*f)->status = F_UNUSED;
+			}
+
+		} else if ((*f)->status == F_ERROR)
+			(*f)->status = F_UNUSED; /* grab it again */
+
+		PDBGG("Frame length %li | pack.#%d | pack.len. %d | state %d",
+		      (unsigned long)(*f)->length, i, len, (*f)->status)
+
+	} /* end for */
+
+	/* Resubmit this URB */
+	urb->dev = cam->usbdev;
+	urb->status = 0;
+	spin_lock(&cam->urb_lock);
+	if (cam->streaming)
+		if ((err = usb_submit_urb(urb))) {
+			cam->misconfigured = 1;
+			DBG(1, "Couldn't resubmit the URB: error %d, %s",
+			    err, symbolic(urb_errlist, err));
+		}
+	spin_unlock(&cam->urb_lock);
+
+	/* Wake up the user process */
+	if (waitqueue_active(&cam->wait_queue))
+		wake_up_interruptible(&cam->wait_queue);
+}
+
+
+/*---------------------------------------------------------------------------
+  Setup the URB structures for the isochronous transfer.
+  Submit the URBs so that the data transfer begins.
+  Return 0 on success, a negative number otherwise.
+  ---------------------------------------------------------------------------*/
+static int w9968cf_start_transfer(struct w9968cf_device* cam)
+{
+	struct usb_device *udev = cam->usbdev;
+	struct urb* urb;
+	const u16 p_size = wMaxPacketSize[cam->altsetting-1];
+	u16 w, h, d;
+	int vidcapt;
+	u32 t_size;
+	int err = 0;
+	s8 i, j;
+
+	for (i = 0; i < W9968CF_URBS; i++) {
+		urb = usb_alloc_urb(W9968CF_ISO_PACKETS);
+		cam->urb[i] = urb;
+
+		if (!urb) {
+			for (j = 0; j < i; j++)
+				usb_free_urb(cam->urb[j]);
+			DBG(1, "Couldn't allocate the URB structures.")
+			return -ENOMEM;
+		}
+
+		urb->dev = udev;
+		urb->context = (void*)cam;
+		urb->pipe = usb_rcvisocpipe(udev, 1);
+		urb->transfer_flags = USB_ISO_ASAP;
+		urb->number_of_packets = W9968CF_ISO_PACKETS;
+		urb->complete = w9968cf_urb_complete;
+		urb->transfer_buffer = cam->transfer_buffer[i];
+		urb->transfer_buffer_length = p_size*W9968CF_ISO_PACKETS;
+		urb->interval = 1;
+		for (j = 0; j < W9968CF_ISO_PACKETS; j++) {
+			urb->iso_frame_desc[j].offset = p_size*j;
+			urb->iso_frame_desc[j].length = p_size;
+		}
+	}
+
+	/* Transfer size per frame, in WORD ! */
+	d = cam->hw_depth;
+	w = cam->hw_width;
+	h = cam->hw_height;
+
+	t_size = (w*h*d)/16;
+
+	err = w9968cf_write_reg(cam, 0xbf17, 0x00); /* reset  everything */
+	err += w9968cf_write_reg(cam, 0xbf10, 0x00); /* normal operation */
+
+	/* Transfer size */
+	err += w9968cf_write_reg(cam, t_size & 0xffff, 0x3d); /* low bits */
+	err += w9968cf_write_reg(cam, t_size >> 16, 0x3e);    /* high bits */
+
+	if (cam->vpp_flag & VPP_DECOMPRESSION)
+		err += w9968cf_upload_quantizationtables(cam);
+
+	vidcapt = w9968cf_read_reg(cam, 0x16); /* read picture settings */
+	err += w9968cf_write_reg(cam, vidcapt|0x8000, 0x16); /* capt. enable */
+
+	err += usb_set_interface(udev, 0, cam->altsetting);
+	err += w9968cf_write_reg(cam, 0x8a05, 0x3c); /* USB FIFO enable */
+
+	if (err || (vidcapt < 0)) {
+		for (i = 0; i < W9968CF_URBS; i++)
+			usb_free_urb(cam->urb[i]);
+		DBG(1, "Couldn't tell the camera to start the data transfer.")
+		return err;
+	}
+
+	w9968cf_init_framelist(cam);
+
+	/* Begin to grab into the temporary buffer */
+	cam->frame_tmp.status = F_UNUSED;
+	cam->frame_tmp.queued = 0;
+	cam->frame_current = &cam->frame_tmp;
+
+	if (!(cam->vpp_flag & VPP_DECOMPRESSION))
+		DBG(5, "Isochronous transfer size: %li bytes/frame.",
+		    (unsigned long)t_size*2)
+
+	DBG(5, "Starting the isochronous transfer...")
+
+	/* Submit the URBs */
+	for (i = 0; i < W9968CF_URBS; i++) {
+		err = usb_submit_urb(cam->urb[i]);
+		if (err) {
+			for (j = i-1; j >= 0; j--)
+				if (!usb_unlink_urb(cam->urb[j]))
+					usb_free_urb(cam->urb[j]);
+			DBG(1, "Couldn't send a transfer request to the "
+			       "USB core (error #%d, %s).", err, 
+			    symbolic(urb_errlist, err))
+		}
+	}
+
+	cam->streaming = 1;
+
+	return 0;
+}
+
+
+/*--------------------------------------------------------------------------
+  Stop the isochronous transfer and set alternate setting to 0 (0Mb/s).
+  Return 0 on success, a negative number otherwise.
+  --------------------------------------------------------------------------*/
+static int w9968cf_stop_transfer(struct w9968cf_device* cam)
+{
+	struct usb_device *udev = cam->usbdev;
+	unsigned long lock_flags;
+	int err = 0;
+	s8 i;
+
+	/* This avoids race conditions with usb_submit_urb() 
+	   in the URB completition handler */
+	spin_lock_irqsave(&cam->urb_lock, lock_flags);
+	cam->streaming = 0;
+	spin_unlock_irqrestore(&cam->urb_lock, lock_flags);
+
+	for (i = W9968CF_URBS-1; i >= 0; i--)
+		if (cam->urb[i])
+			if (!usb_unlink_urb(cam->urb[i])) {
+				usb_free_urb(cam->urb[i]);
+				cam->urb[i] = NULL;
+			}
+
+	if (cam->disconnected)
+		goto exit;
+
+	err = w9968cf_write_reg(cam, 0x0a05, 0x3c); /* stop USB transfer */
+	err += usb_set_interface(udev, 0, 0); /* 0 Mb/s */
+	err += w9968cf_write_reg(cam, 0x0000, 0x39); /* disable JPEG encoder */
+	err += w9968cf_write_reg(cam, 0x0000, 0x16); /* stop video capture */
+
+	if (err) {
+		DBG(2, "Failed to tell the camera to stop the isochronous "
+		       "transfer. However this is not a critical error.")
+		return -EIO;
+	}
+
+exit:
+	DBG(5, "Isochronous transfer stopped.")
+	return 0;
+}
+
+
+/*--------------------------------------------------------------------------
+  Write a W9968CF register. 
+  Return 0 on success, -1 otherwise.
+  --------------------------------------------------------------------------*/
+static int w9968cf_write_reg(struct w9968cf_device* cam, u16 value, u16 index)
+{
+	struct usb_device* udev = cam->usbdev;
+	int res;
+
+	res = usb_control_msg(udev, usb_sndctrlpipe(udev, 0), 0,
+	                      USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE,
+	                      value, index, NULL, 0, W9968CF_USB_CTRL_TIMEOUT);
+
+	if (res < 0)
+		DBG(4, "Failed to write a register "
+		       "(value 0x%04X, index 0x%02X, error #%d, %s).",
+		    value, index, res, symbolic(urb_errlist, res))
+
+	return (res >= 0) ? 0 : -1;
+}
+
+
+/*--------------------------------------------------------------------------
+  Read a W9968CF register. 
+  Return the register value on success, -1 otherwise.
+  --------------------------------------------------------------------------*/
+static int w9968cf_read_reg(struct w9968cf_device* cam, u16 index)
+{
+	struct usb_device* udev = cam->usbdev;
+	u16* buff = cam->control_buffer;
+	int res;
+
+	res = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0), 1,
+	                      USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+	                      0, index, (void*)buff,
+	                      2, W9968CF_USB_CTRL_TIMEOUT);
+
+	if (res < 0)
+		DBG(4, "Failed to read a register "
+		       "(index 0x%02X, error #%d, %s).",
+		    index, res, symbolic(urb_errlist, res))
+
+	return (res >= 0) ? (int)(*buff) : -1;
+}
+
+
+/*--------------------------------------------------------------------------
+  Write data to the fast serial bus registers.
+  Return 0 on success, -1 otherwise.
+  --------------------------------------------------------------------------*/
+static int w9968cf_write_fsb(struct w9968cf_device* cam, u16* data)
+{
+	struct usb_device* udev = cam->usbdev;
+	u16 value;
+	int res;
+
+	value = *data++;
+
+	res = usb_control_msg(udev, usb_sndctrlpipe(udev, 0), 0,
+	                      USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE,
+	                      value, 0x06, (void*)data, 6,
+	                      W9968CF_USB_CTRL_TIMEOUT);
+
+	if (res < 0)
+		DBG(4, "Failed to write the FSB registers "
+		       "(error #%d, %s).", res, symbolic(urb_errlist, res))
+
+	return (res >= 0) ? 0 : -1;
+}
+
+
+/*--------------------------------------------------------------------------
+  Write data to the serial bus control register.
+  Return 0 on success, a negative number otherwise.
+  --------------------------------------------------------------------------*/
+static int w9968cf_write_sb(struct w9968cf_device* cam, u16 value)
+{
+	int err = 0;
+
+	err = w9968cf_write_reg(cam, value, 0x01);
+	udelay(W9968CF_I2C_BUS_DELAY);
+
+	return err;
+}
+
+
+/*--------------------------------------------------------------------------
+  Read data from the serial bus control register.
+  Return 0 on success, a negative number otherwise.
+  --------------------------------------------------------------------------*/
+static int w9968cf_read_sb(struct w9968cf_device* cam)
+{
+	int v = 0;
+
+	v = w9968cf_read_reg(cam, 0x01);
+	udelay(W9968CF_I2C_BUS_DELAY);
+
+	return v;
+}
+
+
+/*--------------------------------------------------------------------------
+  Upload quantization tables for the JPEG compression.
+  This function is called by w9968cf_start_transfer().
+  Return 0 on success, a negative number otherwise.
+  --------------------------------------------------------------------------*/
+static int w9968cf_upload_quantizationtables(struct w9968cf_device* cam)
+{
+	u16 a, b;
+	int err = 0, i, j;
+
+	err += w9968cf_write_reg(cam, 0x0010, 0x39); /* JPEG clock enable */
+
+	for (i = 0, j = 0; i < 32; i++, j += 2) {
+		a = Y_QUANTABLE[j] | ((unsigned)(Y_QUANTABLE[j+1]) << 8);
+		b = UV_QUANTABLE[j] | ((unsigned)(UV_QUANTABLE[j+1]) << 8);
+		err += w9968cf_write_reg(cam, a, 0x40+i);
+		err += w9968cf_write_reg(cam, b, 0x60+i);
+	}
+	err += w9968cf_write_reg(cam, 0x0012, 0x39); /* JPEG encoder enable */
+
+	return err;
+}
+
+
+
+/****************************************************************************
+ * Low-level I2C I/O functions.                                             *
+ * The adapter supports the following I2C transfer functions:               *
+ * i2c_adap_fastwrite_byte_data() (at 400 kHz bit frequency only)           *
+ * i2c_adap_read_byte_data()                                                *
+ * i2c_adap_read_byte()                                                     *
+ ****************************************************************************/
+
+static int w9968cf_smbus_start(struct w9968cf_device* cam)
+{
+	int err = 0;
+
+	err += w9968cf_write_sb(cam, 0x0011); /* SDE=1, SDA=0, SCL=1 */
+	err += w9968cf_write_sb(cam, 0x0010); /* SDE=1, SDA=0, SCL=0 */
+
+	return err;
+}
+
+
+static int w9968cf_smbus_stop(struct w9968cf_device* cam)
+{
+	int err = 0;
+
+	err += w9968cf_write_sb(cam, 0x0011); /* SDE=1, SDA=0, SCL=1 */
+	err += w9968cf_write_sb(cam, 0x0013); /* SDE=1, SDA=1, SCL=1 */
+
+	return err;
+}
+
+
+static int w9968cf_smbus_write_byte(struct w9968cf_device* cam, u8 v)
+{
+	u8 bit;
+	int err = 0, sda;
+
+	for (bit = 0 ; bit < 8 ; bit++) {
+		sda = (v & 0x80) ? 2 : 0;
+		v <<= 1;
+		/* SDE=1, SDA=sda, SCL=0 */
+		err += w9968cf_write_sb(cam, 0x10 | sda);
+		/* SDE=1, SDA=sda, SCL=1 */
+		err += w9968cf_write_sb(cam, 0x11 | sda);
+		/* SDE=1, SDA=sda, SCL=0 */
+		err += w9968cf_write_sb(cam, 0x10 | sda);
+	}
+
+	return err;
+}
+
+
+static int w9968cf_smbus_read_byte(struct w9968cf_device* cam, u8* v)
+{
+	u8 bit;
+	int err = 0;
+
+	*v = 0;
+	for (bit = 0 ; bit < 8 ; bit++) {
+		*v <<= 1;
+		err += w9968cf_write_sb(cam, 0x0013);
+		*v |= (w9968cf_read_sb(cam) & 0x0008) ? 1 : 0;
+		err += w9968cf_write_sb(cam, 0x0012);
+	}
+
+	return err;
+}
+
+
+static int w9968cf_smbus_write_ack(struct w9968cf_device* cam)
+{
+	int err = 0;
+
+	err += w9968cf_write_sb(cam, 0x0010); /* SDE=1, SDA=0, SCL=0 */
+	err += w9968cf_write_sb(cam, 0x0011); /* SDE=1, SDA=0, SCL=1 */
+	err += w9968cf_write_sb(cam, 0x0010); /* SDE=1, SDA=0, SCL=0 */
+
+	return err;
+}
+
+
+static int w9968cf_smbus_read_ack(struct w9968cf_device* cam)
+{
+	int err = 0, sda;
+
+	err += w9968cf_write_sb(cam, 0x0013); /* SDE=1, SDA=1, SCL=1 */
+	sda = (w9968cf_read_sb(cam) & 0x08) ? 1 : 0; /* sda = SDA */
+	err += w9968cf_write_sb(cam, 0x0012); /* SDE=1, SDA=1, SCL=0 */
+	if (sda < 0)
+		err += sda;
+	if (sda == 1) {
+		DBG(6, "Couldn't receive the ACK.")
+		err += -1;
+	}
+
+	return err;
+}
+
+
+/* SMBus protocol: S Addr Wr [A] Subaddr [A] Value [A] P */
+static int 
+w9968cf_i2c_adap_fastwrite_byte_data(struct w9968cf_device* cam, 
+                                     u16 address, u8 subaddress,u8 value)
+{
+	u16* data = cam->data_buffer;
+	int err = 0;
+
+	 /* Enable SBUS outputs */
+	err += w9968cf_write_reg(cam, 0x0020, 0x01);
+
+	data[0] = 0x082f | ((address & 0x80) ? 0x1500 : 0x0);
+	data[0] |= (address & 0x40) ? 0x4000 : 0x0;
+	data[1] = 0x2082 | ((address & 0x40) ? 0x0005 : 0x0);
+	data[1] |= (address & 0x20) ? 0x0150 : 0x0;
+	data[1] |= (address & 0x10) ? 0x5400 : 0x0;
+	data[2] = 0x8208 | ((address & 0x08) ? 0x0015 : 0x0);
+	data[2] |= (address & 0x04) ? 0x0540 : 0x0;
+	data[2] |= (address & 0x02) ? 0x5000 : 0x0;
+	data[3] = 0x1d20 | ((address & 0x02) ? 0x0001 : 0x0);
+	data[3] |= (address & 0x01) ? 0x0054 : 0x0;
+
+	err += w9968cf_write_fsb(cam, data);
+
+	data[0] = 0x8208 | ((subaddress & 0x80) ? 0x0015 : 0x0);
+	data[0] |= (subaddress & 0x40) ? 0x0540 : 0x0;
+	data[0] |= (subaddress & 0x20) ? 0x5000 : 0x0;
+	data[1] = 0x0820 | ((subaddress & 0x20) ? 0x0001 : 0x0);
+	data[1] |= (subaddress & 0x10) ? 0x0054 : 0x0;
+	data[1] |= (subaddress & 0x08) ? 0x1500 : 0x0;
+	data[1] |= (subaddress & 0x04) ? 0x4000 : 0x0;
+	data[2] = 0x2082 | ((subaddress & 0x04) ? 0x0005 : 0x0);
+	data[2] |= (subaddress & 0x02) ? 0x0150 : 0x0;
+	data[2] |= (subaddress & 0x01) ? 0x5400 : 0x0;
+	data[3] = 0x001d;
+
+	err += w9968cf_write_fsb(cam, data);
+
+	data[0] = 0x8208 | ((value & 0x80) ? 0x0015 : 0x0);
+	data[0] |= (value & 0x40) ? 0x0540 : 0x0;
+	data[0] |= (value & 0x20) ? 0x5000 : 0x0;
+	data[1] = 0x0820 | ((value & 0x20) ? 0x0001 : 0x0);
+	data[1] |= (value & 0x10) ? 0x0054 : 0x0;
+	data[1] |= (value & 0x08) ? 0x1500 : 0x0;
+	data[1] |= (value & 0x04) ? 0x4000 : 0x0;
+	data[2] = 0x2082 | ((value & 0x04) ? 0x0005 : 0x0);
+	data[2] |= (value & 0x02) ? 0x0150 : 0x0;
+	data[2] |= (value & 0x01) ? 0x5400 : 0x0;
+	data[3] = 0xfe1d;
+
+	err += w9968cf_write_fsb(cam, data);
+
+	/* Disable SBUS outputs */
+	err += w9968cf_write_reg(cam, 0x0000, 0x01);
+
+	if (!err)
+		DBG(5, "I2C write byte data done, addr.0x%04X, subaddr.0x%02X "
+		       "value 0x%02X.", address, subaddress, value)
+	else
+		DBG(5, "I2C write byte data failed, addr.0x%04X, "
+		       "subaddr.0x%02X, value 0x%02X.", 
+	            address, subaddress, value)
+
+	return err;
+}
+
+
+/* SMBus protocol: S Addr Wr [A] Subaddr [A] P S Addr+1 Rd [A] [Value] NA P */
+static int 
+w9968cf_i2c_adap_read_byte_data(struct w9968cf_device* cam, 
+                                u16 address, u8 subaddress, 
+                                u8* value)
+{
+	int err = 0;
+
+	/* Serial data enable */
+	err += w9968cf_write_sb(cam, 0x0013); /* don't change ! */
+
+	err += w9968cf_smbus_start(cam);
+	err += w9968cf_smbus_write_byte(cam, address);
+	err += w9968cf_smbus_read_ack(cam);
+	err += w9968cf_smbus_write_byte(cam, subaddress);
+	err += w9968cf_smbus_read_ack(cam);
+	err += w9968cf_smbus_stop(cam);
+	err += w9968cf_smbus_start(cam);
+	err += w9968cf_smbus_write_byte(cam, address + 1);
+	err += w9968cf_smbus_read_ack(cam);
+	err += w9968cf_smbus_read_byte(cam, value);
+	err += w9968cf_smbus_write_ack(cam);
+	err += w9968cf_smbus_stop(cam);
+ 
+	/* Serial data disable */
+	err += w9968cf_write_sb(cam, 0x0000);
+
+	if (!err)
+		DBG(5, "I2C read byte data done, addr.0x%04X, "
+		       "subaddr.0x%02X, value 0x%02X.", 
+		    address, subaddress, *value)
+	else
+		DBG(5, "I2C read byte data failed, addr.0x%04X, "
+		       "subaddr.0x%02X, wrong value 0x%02X.",
+		    address, subaddress, *value)
+
+	return err;
+}
+
+
+/* SMBus protocol: S Addr+1 Rd [A] [Value] NA P */
+static int 
+w9968cf_i2c_adap_read_byte(struct w9968cf_device* cam,
+                           u16 address, u8* value)
+{
+	int err = 0;
+
+	/* Serial data enable */
+	err += w9968cf_write_sb(cam, 0x0013);
+
+	err += w9968cf_smbus_start(cam);
+	err += w9968cf_smbus_write_byte(cam, address + 1);
+	err += w9968cf_smbus_read_ack(cam);
+	err += w9968cf_smbus_read_byte(cam, value);
+	err += w9968cf_smbus_write_ack(cam);
+	err += w9968cf_smbus_stop(cam);
+ 
+	/* Serial data disable */
+	err += w9968cf_write_sb(cam, 0x0000);
+
+	if (!err)
+		DBG(5, "I2C read byte done, addr.0x%04X."
+		       "value 0x%02X.", address, *value)
+	else
+		DBG(5, "I2C read byte failed, addr.0x%04X."
+		       "wrong value 0x%02X.", address, *value)
+
+	return err;
+}
+
+
+/* SMBus protocol: S Addr Wr [A] Value [A] P */
+static int 
+w9968cf_i2c_adap_write_byte(struct w9968cf_device* cam,
+                            u16 address, u8 value)
+{
+	DBG(4, "i2c_write_byte() is an unsupported transfer mode.")
+	return -EINVAL;
+}
+
+
+
+/****************************************************************************
+ * I2C interface to kernel                                                  *
+ ****************************************************************************/
+
+static int
+w9968cf_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, 
+                       unsigned short flags, char read_write, u8 command,
+                       int size, union i2c_smbus_data *data)
+{
+	struct w9968cf_device* cam = adapter->data;
+	u8 i, j;
+	int rc = 0, err = 0; 
+
+	switch (addr) {
+		case OV6xx0_SID:
+		case OV7xx0_SID:
+			break;
+		default:
+			DBG(4, "Rejected slave ID 0x%04X", addr)
+			return -EINVAL;
+	}
+
+	if (size == I2C_SMBUS_BYTE) {
+		/* Why addr <<= 1? See OVXXX0_SID defines in ovcamchip.h */
+		addr <<= 1;
+
+		if (read_write == I2C_SMBUS_WRITE)
+ 			rc = w9968cf_i2c_adap_write_byte(cam, addr, command);
+		else if (read_write == I2C_SMBUS_READ) 
+			rc = w9968cf_i2c_adap_read_byte(cam,addr, &data->byte);
+
+	} else if (size == I2C_SMBUS_BYTE_DATA) {
+		addr <<= 1;
+
+		if (read_write == I2C_SMBUS_WRITE)
+ 			rc = w9968cf_i2c_adap_fastwrite_byte_data(cam, addr,
+			                                  command, data->byte);
+		else if (read_write == I2C_SMBUS_READ) {
+			for (i = 1; i <= W9968CF_I2C_RW_RETRIES; i++) {
+				rc = w9968cf_i2c_adap_read_byte_data(cam, addr, 
+				                         command, &data->byte);
+				if (rc < 0) {
+					/* Work around: this seems to wake up  
+					   the EEPROM from the stall state */
+					for (j = 0; j <= 10; j++) {
+					   err += w9968cf_write_sb(cam,0x0020);
+					   err += w9968cf_write_sb(cam,0x0000);
+					   if (err)
+					   	break;
+					}
+				}
+				else
+					break;
+			}
+
+		} else
+			return -EINVAL;
+
+	} else {
+		DBG(4, "Unsupported I2C transfer mode (%d)", size)
+		return -EINVAL;
+	}
+
+	/* This works around a bug in the I2C core */
+	if (rc > 0)
+		rc = 0;
+
+	return rc;
+}
+
+
+static u32 w9968cf_i2c_func(struct i2c_adapter* adap)
+{
+	return I2C_FUNC_SMBUS_READ_BYTE |
+	       I2C_FUNC_SMBUS_READ_BYTE_DATA  |
+	       I2C_FUNC_SMBUS_WRITE_BYTE_DATA;
+}
+
+
+static int w9968cf_i2c_attach_inform(struct i2c_client* client)
+{
+	struct w9968cf_device* cam = client->adapter->data;
+	const char* clientname = client->name;
+	int id = client->driver->id;
+
+	if (id == I2C_DRIVERID_OVCAMCHIP) {
+		int rc = 0;
+
+		cam->sensor_client = client;
+
+		rc = w9968cf_sensor_cmd(cam, OVCAMCHIP_CMD_INITIALIZE, 
+		                        &cam->sensor_mono);
+		if (rc < 0) {
+			DBG(1, "CMOS sensor initialization failed (rc=%d)",rc);
+			cam->sensor_client = NULL;
+			return rc;
+		}
+
+		if (w9968cf_sensor_cmd(cam, OVCAMCHIP_CMD_Q_SUBTYPE, 
+		                       &cam->sensor) < 0)
+			rc = -EIO;
+		else if (client->addr==OV7xx0_SID || client->addr==OV6xx0_SID)
+			w9968cf_sensor_configure(cam);
+		else
+			rc = -EINVAL;
+
+		if (rc < 0) {
+			cam->sensor_client = NULL;
+			cam->sensor = CC_UNKNOWN;
+			return rc;
+		}
+	} else	{
+		DBG(4, "Rejected client [%s] with [%s]", 
+		    clientname, client->driver->name)
+		return -1;
+	}
+
+	DBG(2, "I2C attach client [%s] with [%s]",
+	    clientname, client->driver->name)
+
+	return 0;
+}
+
+
+static int w9968cf_i2c_detach_inform(struct i2c_client* client)
+{
+	struct w9968cf_device* cam = client->adapter->data;
+	const char* clientname = client->name;
+
+	if (cam->sensor_client == client) {
+		cam->sensor_client = NULL;
+	}
+
+	DBG(2, "I2C detach [%s]", clientname)
+
+	return 0;
+}
+
+
+static int 
+w9968cf_i2c_control(struct i2c_adapter* adapter, unsigned int cmd,
+                    unsigned long arg)
+{
+	return 0;
+}
+
+
+static void w9968cf_i2c_inc_use(struct i2c_adapter* adap)
+{
+	MOD_INC_USE_COUNT;
+}
+
+
+static void w9968cf_i2c_dec_use(struct i2c_adapter* adap)
+{
+	MOD_DEC_USE_COUNT;
+}
+
+
+static int w9968cf_i2c_init(struct w9968cf_device* cam)
+{
+	int rc = 0;
+
+	static struct i2c_algorithm algo = {
+		.name =          "W996[87]CF algorithm",
+		.id =            I2C_ALGO_SMBUS,
+		.smbus_xfer =    w9968cf_i2c_smbus_xfer,
+		.algo_control =  w9968cf_i2c_control,
+		.functionality = w9968cf_i2c_func,
+	};
+
+	static struct i2c_adapter adap = {
+		.id =                I2C_ALGO_SMBUS | I2C_HW_SMBUS_W9968CF,
+		.inc_use =           w9968cf_i2c_inc_use,
+		.dec_use =           w9968cf_i2c_dec_use,
+		.client_register =   w9968cf_i2c_attach_inform,
+		.client_unregister = w9968cf_i2c_detach_inform,
+		.algo =              &algo,
+	};
+
+	memcpy(&cam->i2c_adapter, &adap, sizeof(struct i2c_adapter));
+	strcpy(cam->i2c_adapter.name, "w9968cf");
+	cam->i2c_adapter.data = cam;
+
+	DBG(6, "Registering I2C bus with kernel...")
+
+	rc = i2c_add_adapter(&cam->i2c_adapter);
+	if (rc)
+		DBG(5, "Failed to register the I2C bus.")
+	else
+		DBG(5, "I2C bus registered.")
+
+	return rc;
+}
+
+
+
+/****************************************************************************
+ * Helper functions                                                         *
+ ****************************************************************************/
+
+/*--------------------------------------------------------------------------
+  Turn on the LED on some webcams. A beep should be heard too.
+  Return 0 on success, a negative number otherwise.
+  --------------------------------------------------------------------------*/
+static int w9968cf_turn_on_led(struct w9968cf_device* cam)
+{
+	int err = 0;
+
+	err += w9968cf_write_reg(cam, 0xff00, 0x00); /* power-down */
+	err += w9968cf_write_reg(cam, 0xbf17, 0x00); /* reset everything */
+	err += w9968cf_write_reg(cam, 0xbf10, 0x00); /* normal operation */
+	err += w9968cf_write_reg(cam, 0x0010, 0x01); /* serial bus, SDS high */
+	err += w9968cf_write_reg(cam, 0x0000, 0x01); /* serial bus, SDS low */
+	err += w9968cf_write_reg(cam, 0x0010, 0x01); /* ..high 'beep-beep' */
+
+	if (err)
+		DBG(2, "Couldn't turn on the LED.")
+
+	DBG(5, "LED turned on.")
+
+	return err;
+}
+
+
+/*--------------------------------------------------------------------------
+  Write some registers for the device initialization.
+  This function is called once on open().
+  Return 0 on success, a negative number otherwise.
+  --------------------------------------------------------------------------*/
+static int w9968cf_init_chip(struct w9968cf_device* cam)
+{
+	int err = 0, rc = 0;
+
+	err += w9968cf_write_reg(cam, 0xff00, 0x00); /* power off */
+	err += w9968cf_write_reg(cam, 0xbf10, 0x00); /* power on */
+
+	err += w9968cf_write_reg(cam, 0x405d, 0x03); /* DRAM timings */
+	err += w9968cf_write_reg(cam, 0x0030, 0x04); /* SDRAM timings */
+
+	err += w9968cf_write_reg(cam, 0x0000, 0x20); /* Y frame buf.0, low */
+	err += w9968cf_write_reg(cam, 0x0000, 0x21); /* Y frame buf.0, high */
+	err += w9968cf_write_reg(cam, 0xb000, 0x22); /* Y frame buf.1, low */
+	err += w9968cf_write_reg(cam, 0x0004, 0x23); /* Y frame buf.1, high */
+	err += w9968cf_write_reg(cam, 0x5800, 0x24); /* U frame buf.0, low */
+	err += w9968cf_write_reg(cam, 0x0002, 0x25); /* U frame buf.0, high */
+	err += w9968cf_write_reg(cam, 0x0800, 0x26); /* U frame buf.1, low */
+	err += w9968cf_write_reg(cam, 0x0007, 0x27); /* U frame buf.1, high */
+	err += w9968cf_write_reg(cam, 0x8400, 0x28); /* V frame buf.0, low */
+	err += w9968cf_write_reg(cam, 0x0003, 0x29); /* V frame buf.0, high */
+	err += w9968cf_write_reg(cam, 0x3400, 0x2a); /* V frame buf.1, low */
+	err += w9968cf_write_reg(cam, 0x0008, 0x2b); /* V frame buf.1, high */
+
+	err += w9968cf_write_reg(cam, 0x6000, 0x32); /* JPEG bitstream buf 0 */
+	err += w9968cf_write_reg(cam, 0x0009, 0x33); /* JPEG bitstream buf 0 */
+	err += w9968cf_write_reg(cam, 0x2000, 0x34); /* JPEG bitstream buf 1 */
+	err += w9968cf_write_reg(cam, 0x000d, 0x35); /* JPEG bitstream buf 1 */
+
+	err += w9968cf_write_reg(cam, 0x0000, 0x36);/* JPEG restart interval */
+	err += w9968cf_write_reg(cam, 0x0804, 0x37);/*JPEG VLE FIFO threshold*/
+	err += w9968cf_write_reg(cam, 0x0000, 0x38);/* disable hw up-scaling */
+	err += w9968cf_write_reg(cam, 0x0000, 0x3f); /* JPEG/MCTL test data */
+
+	err += w9968cf_set_picture(cam, cam->picture); /* this before */
+	err += w9968cf_set_window(cam, cam->window);
+
+	if (err)
+		goto error;
+
+	rc = w9968cf_sensor_change_settings(cam);
+	if (rc)
+		goto error;
+
+	DBG(5, "Chip successfully initialized.");
+	
+	return 0;
+
+error:
+	DBG(1, "Chip initialization failed.")
+	if (err)
+		return err;
+	else
+		return rc;
+}
+
+
+/*--------------------------------------------------------------------------
+  Change the picture settings of the camera.
+  Return 0 on success, a negative number otherwise.
+  --------------------------------------------------------------------------*/
+static int
+w9968cf_set_picture(struct w9968cf_device* cam, struct video_picture pict)
+{
+	u16 fmt, hw_depth, hw_palette, reg_v = 0x0000;
+	int err = 0, rc = 0;
+
+	/* Make sure we are using a valid depth */
+	pict.depth = w9968cf_valid_depth(pict.palette);
+
+	fmt = pict.palette;
+
+	hw_depth = pict.depth; /* depth used by the winbond chip */
+	hw_palette = pict.palette; /* palette used by the winbond chip */
+
+	/* VS & HS polarities */
+	reg_v = (cam->vs_polarity << 12) | (cam->hs_polarity << 11);
+
+	switch (fmt)
+	{
+		case VIDEO_PALETTE_UYVY:
+			reg_v |= 0x0000;
+			cam->vpp_flag = VPP_NONE;
+			break;
+		case VIDEO_PALETTE_YUV422P:
+			reg_v |= 0x0002;
+			cam->vpp_flag = VPP_DECOMPRESSION;
+			break;
+		case VIDEO_PALETTE_YUV420:
+		case VIDEO_PALETTE_YUV420P:
+			reg_v |= 0x0003;
+			cam->vpp_flag = VPP_DECOMPRESSION;
+			break;
+		case VIDEO_PALETTE_YUYV:
+		case VIDEO_PALETTE_YUV422:
+			reg_v |= 0x0000;
+			cam->vpp_flag = VPP_SWAP_YUV_BYTES;
+			hw_palette = VIDEO_PALETTE_UYVY;
+			break;
+		/* Original video is used instead of RGBX palettes. 
+		   Software conversion later. */
+		case VIDEO_PALETTE_GREY:
+		case VIDEO_PALETTE_RGB555:
+		case VIDEO_PALETTE_RGB565:
+		case VIDEO_PALETTE_RGB24:
+		case VIDEO_PALETTE_RGB32:
+			reg_v |= 0x0000; /* UYVY 16 bit is used */
+			hw_depth = 16;
+			hw_palette = VIDEO_PALETTE_UYVY;
+			cam->vpp_flag = VPP_UYVY_TO_RGBX;
+			break;
+	}
+
+	/* FIXME: 'hardware double buffer' doesn't work when compressed video
+	          is enabled (corrupted frames). */
+	if (cam->double_buffer && !(cam->vpp_flag & VPP_DECOMPRESSION))
+		reg_v |= 0x0080;
+
+	if (cam->clamping)
+		reg_v |= 0x0020;
+
+	if (cam->filter_type == 1)
+		reg_v |= 0x0008;
+	else if (cam->filter_type == 2)
+		reg_v |= 0x000c;
+
+	err = w9968cf_write_reg(cam, reg_v, 0x16);
+	if (err)
+		goto error;
+
+	rc = w9968cf_sensor_set_picture(cam, pict);
+	if (rc)
+		goto error;
+
+	/* If all went well, update the device data structure */
+	memcpy(&cam->picture, &pict, sizeof(pict));
+	cam->hw_depth = hw_depth;
+	cam->hw_palette = hw_palette;
+
+	/* Settings changed, so we clear the frame buffers */
+	memset(cam->frame[0].buffer, 0, 
+	       cam->nbuffers*w9968cf_get_max_bufsize(cam));
+
+	DBG(4, "Palette is %s, depth is %d bpp.",
+	    symbolic(v4l1_plist, pict.palette), pict.depth)
+
+	return 0;
+
+error:
+	DBG(1, "Failed to change picture settings.")
+	if (err)
+		return err;
+	else 
+		return rc;
+}
+
+
+/*--------------------------------------------------------------------------
+  Change the capture area size of the camera.
+  This function _must_ be called _after_ w9968cf_set_picture().
+  Return 0 on success, a negative number otherwise.
+  --------------------------------------------------------------------------*/
+static int
+w9968cf_set_window(struct w9968cf_device* cam, struct video_window win)
+{
+	u16 x, y, w, h, scx, scy, cw, ch, ax, ay;
+	unsigned long fw, fh;
+	struct ovcamchip_window s_win;
+	int err=0, rc=0;
+
+	/* Work around to avoid FP arithmetics */
+	#define __SC(x) ((x) << 10)
+	#define __UNSC(x) ((x) >> 10)
+
+	/* Make sure we are using a supported resolution */
+	if ((err = w9968cf_adjust_window_size(cam, (u16*)&win.width, 
+	                                      (u16*)&win.height)))
+		goto error;
+
+	/* Scaling factors */
+	fw = __SC(win.width) / cam->maxwidth;
+	fh = __SC(win.height) / cam->maxheight;
+
+	/* Set up the width and height values used by the chip */
+	if ((win.width > cam->maxwidth) || (win.height > cam->maxheight)) {
+		cam->vpp_flag |= VPP_UPSCALE;
+		/* Calculate largest w,h mantaining the same w/h ratio */
+		w = (fw >= fh) ? cam->maxwidth : __SC(win.width)/fh;
+		h = (fw >= fh) ? __SC(win.height)/fw : cam->maxheight;
+		if (w < cam->minwidth) /* just in case */
+			w = cam->minwidth;
+		if (h < cam->minheight) /* just in case */
+			h = cam->minheight;
+	} else {
+		cam->vpp_flag &= ~VPP_UPSCALE;
+		w = win.width;
+		h = win.height;
+	}
+
+	/* x,y offsets of the cropped area */
+	scx = cam->start_cropx;
+	scy = cam->start_cropy;
+
+	/* Calculate cropped area manteining the right w/h ratio */
+	if (cam->largeview && !(cam->vpp_flag & VPP_UPSCALE)) {
+		cw = (fw >= fh) ? cam->maxwidth : __SC(win.width)/fh;
+		ch = (fw >= fh) ? __SC(win.height)/fw : cam->maxheight;
+	} else {
+		cw = w;
+		ch = h;
+	}
+
+	/* Setup the sensor window */
+	s_win.format = SENSOR_FORMAT;
+	s_win.width = cam->maxwidth;
+	s_win.height = cam->maxheight;
+	s_win.quarter = 0; /* full progressive video */
+
+	/* Center it */
+	s_win.x = (s_win.width - cw) / 2;
+	s_win.y = (s_win.height - ch) / 2;
+
+	/* Clock divisor */
+	if (cam->clockdiv >= 0)
+		s_win.clockdiv = cam->clockdiv; /* manual override */
+	else
+		switch (cam->sensor) {
+			case CC_OV6620:
+				s_win.clockdiv = 0;
+				break;
+			case CC_OV6630:
+				s_win.clockdiv = 0;
+				break;
+			case CC_OV76BE:
+			case CC_OV7610:
+			case CC_OV7620:
+				s_win.clockdiv = 0;
+				break;
+			default:
+				s_win.clockdiv = W9968CF_DEF_CLOCKDIVISOR;
+		}
+
+	/* We have to scale win.x and win.y offsets */	
+	if ( (cam->largeview && !(cam->vpp_flag & VPP_UPSCALE))
+	     || (cam->vpp_flag & VPP_UPSCALE) ) {
+		ax = __SC(win.x)/fw;
+		ay = __SC(win.y)/fh;
+	} else {
+		ax = win.x;
+		ay = win.y;
+	}
+
+	if ((ax + cw) > cam->maxwidth)
+		ax = cam->maxwidth - cw;
+
+	if ((ay + ch) > cam->maxheight)
+		ay = cam->maxheight - ch;
+
+	/* Adjust win.x, win.y */
+	if ( (cam->largeview && !(cam->vpp_flag & VPP_UPSCALE))
+	     || (cam->vpp_flag & VPP_UPSCALE) ) {
+		win.x = __UNSC(ax*fw);
+		win.y = __UNSC(ay*fh);
+	} else {
+		win.x = ax;
+		win.y = ay;
+	}
+
+	/* Offsets used by the chip */
+	x = ax + s_win.x;
+	y = ay + s_win.y;
+
+	/* Go ! */
+	if ((rc = w9968cf_sensor_cmd(cam, OVCAMCHIP_CMD_S_MODE, &s_win)))
+		goto error;
+
+	err += w9968cf_write_reg(cam, scx + x, 0x10);
+	err += w9968cf_write_reg(cam, scy + y, 0x11);
+	err += w9968cf_write_reg(cam, scx + x + cw, 0x12);
+	err += w9968cf_write_reg(cam, scy + y + ch, 0x13);
+	err += w9968cf_write_reg(cam, w, 0x14);
+	err += w9968cf_write_reg(cam, h, 0x15);
+
+	/* JPEG width & height */
+	err += w9968cf_write_reg(cam, w, 0x30);
+	err += w9968cf_write_reg(cam, h, 0x31);
+
+	/* Y & UV frame buffer strides (in WORD) */
+	if (cam->vpp_flag & VPP_DECOMPRESSION) {
+		err += w9968cf_write_reg(cam, w/2, 0x2c);
+		err += w9968cf_write_reg(cam, w/4, 0x2d);
+	} else
+		err += w9968cf_write_reg(cam, w, 0x2c);
+
+	if (err)
+		goto error;
+
+	/* If all went well, update the device data structure */
+	memcpy(&cam->window, &win, sizeof(win));
+	cam->hw_width = w;
+	cam->hw_height = h;
+
+	/* Settings changed, so we clear the frame buffers */
+	memset(cam->frame[0].buffer, 0, 
+	       cam->nbuffers*w9968cf_get_max_bufsize(cam));
+
+	DBG(4, "The capture area is %dx%d, Offset (x,y)=(%d,%d).", 
+	    win.width, win.height, win.x, win.y)
+
+	PDBGG("x=%d ,y=%d, w=%d, h=%d, ax=%d, ay=%d, s_win.x=%d, s_win.y=%d, "
+	      "cw=%d, ch=%d, win.x=%d ,win.y=%d, win.width=%d, win.height=%d",
+	      x, y, w, h, ax, ay, s_win.x, s_win.y, cw, ch, win.x, win.y,
+	      win.width, win.height)
+
+	return 0;
+
+error:
+	DBG(1, "Failed to change the capture area size.")
+	if (err)
+		return err;
+	else
+		return rc;
+}
+
+
+/*--------------------------------------------------------------------------
+  Return non-zero if the palette is supported, 0 otherwise.
+  --------------------------------------------------------------------------*/
+static inline u16 w9968cf_valid_palette(u16 palette)
+{
+	u8 i = 0;
+	while (w9968cf_formatlist[i].palette != 0) {
+		if (palette == w9968cf_formatlist[i].palette)
+			return palette;
+		i++;
+	}
+	return 0;
+}
+
+
+/*--------------------------------------------------------------------------
+  Return the depth corresponding to the given palette.
+  Palette _must_ be supported !
+  --------------------------------------------------------------------------*/
+static inline u16 w9968cf_valid_depth(u16 palette)
+{
+	u8 i=0;
+	while (w9968cf_formatlist[i].palette != palette)
+		i++;
+
+	return w9968cf_formatlist[i].depth;
+}
+
+
+/*--------------------------------------------------------------------------
+  Return non-zero if the format requires decompression, 0 otherwise.
+  --------------------------------------------------------------------------*/
+static inline u8 w9968cf_need_decompression(u16 palette)
+{
+	u8 i = 0;
+	while (w9968cf_formatlist[i].palette != 0) {
+		if (palette == w9968cf_formatlist[i].palette)
+			return w9968cf_formatlist[i].compression;
+		i++;
+	}
+	return 0;
+}
+
+
+/*-------------------------------------------------------------------------- 
+  Adjust the asked values for window width and height.
+  Return 0 on success, -1 otherwise.
+  --------------------------------------------------------------------------*/
+static int 
+w9968cf_adjust_window_size(struct w9968cf_device* cam, u16* width, u16* height)
+{
+	u16 maxw, maxh;
+
+	if ((*width < cam->minwidth) || (*height < cam->minheight))
+		return -ERANGE;
+
+	maxw = cam->upscaling && !(cam->vpp_flag & VPP_DECOMPRESSION)
+	       && w9968cf_vppmod_present ? W9968CF_MAX_WIDTH : cam->maxwidth;
+	maxh = cam->upscaling && !(cam->vpp_flag & VPP_DECOMPRESSION)
+	       && w9968cf_vppmod_present ? W9968CF_MAX_HEIGHT : cam->maxheight;
+
+	if (*width > maxw)
+		*width = maxw;
+	if (*height > maxh)
+		*height = maxh;
+
+	if (cam->vpp_flag & VPP_DECOMPRESSION) {
+		*width  &= ~15L; /* multiple of 16 */
+		*height &= ~15L;
+	}
+
+	PDBGG("Window size adjusted w=%d, h=%d ", *width, *height)
+
+	return 0;
+}
+
+
+/*--------------------------------------------------------------------------
+  Initialize the FIFO list of requested frames.
+  --------------------------------------------------------------------------*/
+static void w9968cf_init_framelist(struct w9968cf_device* cam)
+{
+	u8 i;
+
+	for (i = 0; i < cam->nbuffers; i++) {
+		cam->requested_frame[i] = NULL;
+		cam->frame[i].queued = 0;
+		cam->frame[i].status = F_UNUSED;
+	}
+}
+
+
+/*--------------------------------------------------------------------------
+  Add a frame in the FIFO list of requested frames.
+  This function is called in process context.
+  --------------------------------------------------------------------------*/
+static void w9968cf_push_frame(struct w9968cf_device* cam, u8 f_num)
+{
+	u8 f;
+	unsigned long lock_flags;
+
+	spin_lock_irqsave(&cam->flist_lock, lock_flags);
+
+	for (f=0; cam->requested_frame[f] != NULL; f++);
+	cam->requested_frame[f] = &cam->frame[f_num];
+	cam->frame[f_num].queued = 1;
+	cam->frame[f_num].status = F_UNUSED; /* clear the status */
+
+	spin_unlock_irqrestore(&cam->flist_lock, lock_flags);
+
+	DBG(6, "Frame #%d pushed into the FIFO list. Position %d.", f_num, f)
+}
+
+
+/*--------------------------------------------------------------------------
+  Read, store and remove the first pointer in the FIFO list of requested
+  frames. This function is called in interrupt context.
+  --------------------------------------------------------------------------*/
+static void 
+w9968cf_pop_frame(struct w9968cf_device* cam, struct w9968cf_frame_t** framep)
+{
+	u8 i;
+
+	spin_lock(&cam->flist_lock);
+
+	*framep = cam->requested_frame[0];
+
+	/* Shift the list of pointers */
+	for (i = 0; i < cam->nbuffers-1; i++)
+		cam->requested_frame[i] = cam->requested_frame[i+1];
+	cam->requested_frame[i] = NULL;
+
+	spin_unlock(&cam->flist_lock);
+
+	DBG(6,"Popped frame #%d from the list.",*framep-&cam->frame[0])
+}
+
+
+/*--------------------------------------------------------------------------
+  High-level video post-processing routine on grabbed frames.
+  Return 0 on success, a negative number otherwise.
+  --------------------------------------------------------------------------*/
+static int 
+w9968cf_postprocess_frame(struct w9968cf_device* cam, 
+                          struct w9968cf_frame_t* fr)
+{
+	void *pIn = fr->buffer, *pOut = cam->vpp_buffer, *tmp;
+	u16 w = cam->window.width,
+	    h = cam->window.height,
+	    d = cam->picture.depth,
+	    fmt = cam->picture.palette,
+	    rgb = cam->force_rgb,
+	    hw_w = cam->hw_width,
+	    hw_h = cam->hw_height,
+	    hw_d = cam->hw_depth;
+	int err = 0;
+
+	#define _PSWAP(pIn, pOut) {tmp = (pIn); (pIn) = (pOut); (pOut) = tmp;}
+
+	if (cam->vpp_flag & VPP_DECOMPRESSION) {
+		memcpy(pOut, pIn, fr->length);
+		_PSWAP(pIn, pOut)
+		err = (*w9968cf_vpp_decode)(pIn, fr->length, hw_w, hw_h, pOut);
+		PDBGG("Compressed frame length: %li",(unsigned long)fr->length)
+		fr->length = (hw_w*hw_h*hw_d)/8;
+		_PSWAP(pIn, pOut)
+		if (err) {
+			DBG(4, "An error occurred while decoding the frame: "
+			       "%s.", symbolic(decoder_errlist, err))
+			return err;
+		} else
+			DBG(6, "Frame decoded")
+	}
+
+	if (cam->vpp_flag & VPP_SWAP_YUV_BYTES) {
+		(*w9968cf_vpp_swap_yuvbytes)(pIn, fr->length);
+		DBG(6, "Original UYVY component ordering changed.")
+	}
+
+	if (cam->vpp_flag & VPP_UPSCALE) {
+		(*w9968cf_vpp_scale_up)(pIn, pOut, hw_w, hw_h, hw_d, w, h);
+		fr->length = (w*h*hw_d)/8;
+		_PSWAP(pIn, pOut)
+		DBG(6, "Vertical up-scaling done: %d,%d,%dbpp->%d,%d",
+		    hw_w, hw_h, hw_d, w, h)
+	}
+
+	if (cam->vpp_flag & VPP_UYVY_TO_RGBX) {
+		(*w9968cf_vpp_uyvy_to_rgbx)(pIn, fr->length, pOut, fmt, rgb);
+		fr->length = (w*h*d)/8;
+		_PSWAP(pIn, pOut)
+		DBG(6, "UYVY-16bit to %s conversion done.", 
+		    symbolic(v4l1_plist, fmt))
+	}
+
+	if (pOut == fr->buffer)
+		memcpy(fr->buffer, cam->vpp_buffer, fr->length);
+
+	return 0;
+}
+
+
+
+/****************************************************************************
+ * CMOS sensor control routines                                             *
+ ****************************************************************************/
+
+static int 
+w9968cf_sensor_set_control(struct w9968cf_device* cam, int cid, int val)
+{
+	struct ovcamchip_control ctl;
+	int rc;
+
+	ctl.id = cid;
+	ctl.value = val;
+
+	rc = w9968cf_sensor_cmd(cam, OVCAMCHIP_CMD_S_CTRL, &ctl);
+
+	return rc;
+}
+
+static int 
+w9968cf_sensor_get_control(struct w9968cf_device* cam, int cid, int *val)
+{
+	struct ovcamchip_control ctl;
+	int rc;
+
+	ctl.id = cid;
+
+	rc = w9968cf_sensor_cmd(cam, OVCAMCHIP_CMD_G_CTRL, &ctl);
+	if (rc >= 0)
+		*val = ctl.value;
+
+	return rc;
+}
+
+
+static inline int
+w9968cf_sensor_cmd(struct w9968cf_device* cam, unsigned int cmd, void *arg)
+{
+	struct i2c_client* c = cam->sensor_client;
+
+	DBG(6, "Executing CMOS sensor command...")
+
+	if (c && c->driver->command)
+		return c->driver->command(cam->sensor_client, cmd, arg);
+	else
+		return -ENODEV;
+}
+
+
+/*--------------------------------------------------------------------------
+  Change some settings of the CMOS sensor.
+  Returns: 0 for success, a negative number otherwise.
+  --------------------------------------------------------------------------*/
+static int w9968cf_sensor_change_settings(struct w9968cf_device* cam)
+{
+	int rc;
+
+	/* Auto brightness */
+	rc = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_AUTOBRIGHT, 
+	                                cam->auto_brt);
+	if (SENSOR_FATAL_ERROR(rc))
+		return rc;
+
+	/* Auto exposure */
+	rc = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_AUTOEXP, 
+	                                cam->auto_exp);
+	if (SENSOR_FATAL_ERROR(rc))
+		return rc;
+
+	/* Banding filter */
+	rc = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_BANDFILT, 
+	                                cam->bandfilt);
+	if (SENSOR_FATAL_ERROR(rc))
+		return rc;
+
+	/* Light frequency */
+	rc = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_FREQ,
+	                                cam->lightfreq);
+	if (SENSOR_FATAL_ERROR(rc))
+		return rc;
+
+	/* Back light */
+	rc = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_BACKLIGHT,
+	                                cam->backlight);
+	if (SENSOR_FATAL_ERROR(rc))
+		return rc;
+
+	/* Mirror */
+	rc = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_MIRROR,
+	                                cam->mirror);
+	if (SENSOR_FATAL_ERROR(rc))
+		return rc;
+
+	return 0;
+}
+
+
+/*--------------------------------------------------------------------------
+  Get some current picture settings from the CMOS sensor.
+  Returns: 0 for success, a negative number otherwise.
+  --------------------------------------------------------------------------*/
+static int
+w9968cf_sensor_get_picture(struct w9968cf_device* cam, 
+                           struct video_picture* pict)
+{
+	int rc, v;
+
+	/* Don't return error if a setting is unsupported, or rest of settings
+	   will not be performed */
+
+	rc = w9968cf_sensor_get_control(cam, OVCAMCHIP_CID_CONT, &v);
+	if (SENSOR_FATAL_ERROR(rc))
+		return rc;
+	pict->contrast = v;
+
+	rc = w9968cf_sensor_get_control(cam, OVCAMCHIP_CID_BRIGHT, &v);
+	if (SENSOR_FATAL_ERROR(rc))
+		return rc;
+	pict->brightness = v;
+
+	rc = w9968cf_sensor_get_control(cam, OVCAMCHIP_CID_SAT, &v);
+	if (SENSOR_FATAL_ERROR(rc))
+		return rc;
+	pict->colour = v;
+
+	rc = w9968cf_sensor_get_control(cam, OVCAMCHIP_CID_HUE, &v);
+	if (SENSOR_FATAL_ERROR(rc))
+		return rc;
+	pict->hue = v;
+
+	pict->whiteness = W9968CF_WHITENESS; /* to do! */
+
+	DBG(5, "Got picture settings from the CMOS sensor.")
+
+	PDBGG("Brightness, contrast, hue, colour, whiteness are "
+	      "%d,%d,%d,%d,%d.", pict->brightness, pict->contrast,
+	      pict->hue, pict->colour, pict->whiteness)
+
+	return 0;
+}
+
+
+/*--------------------------------------------------------------------------
+  Change picture settings of the CMOS sensor.
+  Returns: 0 for success, a negative number otherwise.
+  --------------------------------------------------------------------------*/
+static int
+w9968cf_sensor_set_picture(struct w9968cf_device* cam, 
+                           struct video_picture pict)
+{
+	int rc;
+
+	rc = w9968cf_sensor_set_control(cam,OVCAMCHIP_CID_CONT, pict.contrast);
+	if (SENSOR_FATAL_ERROR(rc))
+		return rc;
+
+	if (!cam->auto_brt) {
+		rc = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_BRIGHT, 
+	                                        pict.brightness);
+		if (SENSOR_FATAL_ERROR(rc))
+			return rc;
+	}
+
+	rc = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_SAT, pict.colour);
+	if (SENSOR_FATAL_ERROR(rc))
+		return rc;
+
+	rc = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_HUE, pict.hue);
+	if (SENSOR_FATAL_ERROR(rc))
+		return rc;
+
+	PDBGG("Brightness, contrast, hue, colour, whiteness are "
+	      "%d,%d,%d,%d,%d.", pict.brightness, pict.contrast,
+	      pict.hue, pict.colour, pict.whiteness)
+
+	return 0;
+}
+
+
+
+/****************************************************************************
+ * Camera configuration                                                     *
+ ****************************************************************************/
+
+/*--------------------------------------------------------------------------
+  This function is called when the CMOS sensor is detected.
+  --------------------------------------------------------------------------*/
+static void w9968cf_sensor_configure(struct w9968cf_device* cam)
+{
+	/* NOTE: Make sure width and height are a multiple of 16 */
+
+	switch (cam->sensor_client->addr) {
+		case OV6xx0_SID:
+			cam->maxwidth = 352;
+			cam->maxheight = 288;
+			cam->minwidth = 64;
+			cam->minheight = 48;
+			break;
+		case OV7xx0_SID:
+			cam->maxwidth = 640;
+			cam->maxheight = 480;
+			cam->minwidth = 64;
+			cam->minheight = 48;
+			break;
+	}
+
+	/* These values depend on the ones in the ovxxx0.c sources */
+	switch (cam->sensor) {
+		case CC_OV7620:
+			cam->start_cropx = 287;
+			cam->start_cropy = 35;
+			/* Seems to work around a bug in the CMOS sensor */
+			cam->vs_polarity = 1;
+			cam->hs_polarity = 1;
+			break;
+		default:
+			cam->start_cropx = 320;
+			cam->start_cropy = 35;
+			cam->vs_polarity = 1;
+			cam->hs_polarity = 0;
+	}
+
+	DBG(5, "CMOS sensor %s configured.", symbolic(senlist, cam->sensor))
+}
+
+
+/*--------------------------------------------------------------------------
+  Fill some basic fields in the main device data structure.
+  This function is called once on w9968cf_usb_probe() for each recognized 
+  camera.
+  --------------------------------------------------------------------------*/
+static void
+w9968cf_configure_camera(struct w9968cf_device* cam,
+                         struct usb_device* udev,
+                         enum w9968cf_model_id mod_id,
+                         const unsigned short dev_nr)
+{
+#if defined(CONFIG_VIDEO_PROC_FS)
+	init_MUTEX(&cam->procfs_sem);
+#endif
+	init_MUTEX(&cam->fileop_sem);
+	init_waitqueue_head(&cam->open);
+	spin_lock_init(&cam->urb_lock);
+	spin_lock_init(&cam->flist_lock);
+
+	cam->users = 0;
+	cam->disconnected = 0;
+	cam->usbdev = udev;
+	cam->id = mod_id;
+	cam->sensor = CC_UNKNOWN;
+
+	strcpy(cam->v4ldev.name, symbolic(camlist, mod_id));
+	cam->v4ldev.type = VID_TYPE_CAPTURE | VID_TYPE_SCALES;
+	cam->v4ldev.hardware = VID_HARDWARE_W9968CF;
+	cam->v4ldev.fops = &w9968cf_fops;
+	cam->v4ldev.priv = (void*)cam;
+	cam->v4ldev.minor = video_nr[dev_nr];
+
+	/* Calculate the alternate setting number (from 1 to 16)
+	   according to the 'packet_size' module parameter */
+	if (packet_size[dev_nr] < W9968CF_MIN_PACKET_SIZE)
+		packet_size[dev_nr] = W9968CF_MIN_PACKET_SIZE;
+	for (cam->altsetting = 1;
+	     packet_size[dev_nr] < wMaxPacketSize[cam->altsetting-1];
+	     cam->altsetting++);
+
+	cam->max_buffers = (max_buffers[dev_nr] < 2 || 
+	                    max_buffers[dev_nr] > W9968CF_MAX_BUFFERS)
+	                   ? W9968CF_BUFFERS : max_buffers[dev_nr];
+
+	cam->double_buffer = (double_buffer[dev_nr] == 0 || 
+	                      double_buffer[dev_nr] == 1)
+	                     ? double_buffer[dev_nr] : W9968CF_DOUBLE_BUFFER;
+
+	cam->clamping = (clamping[dev_nr] == 0 || clamping[dev_nr] == 1)
+	                ? clamping[dev_nr] : W9968CF_CLAMPING;
+	
+	cam->filter_type = (filter_type[dev_nr] == 0 ||
+	                    filter_type[dev_nr] == 1 ||
+	                    filter_type[dev_nr] == 2)
+	                   ? filter_type[dev_nr] : W9968CF_FILTER_TYPE;
+
+	cam->capture = 1;
+
+	cam->largeview = (largeview[dev_nr] == 0 || largeview[dev_nr] == 1)
+	                 ? largeview[dev_nr] : W9968CF_LARGEVIEW;
+
+	cam->decompression = (decompression[dev_nr] == 0 || 
+	                      decompression[dev_nr] == 1 ||
+	                      decompression[dev_nr] == 2)
+	                     ? decompression[dev_nr] : W9968CF_DECOMPRESSION;
+
+	cam->upscaling = (upscaling[dev_nr] == 0 || 
+	                  upscaling[dev_nr] == 1)
+	                 ? upscaling[dev_nr] : W9968CF_UPSCALING;
+
+	cam->auto_brt = (autobright[dev_nr] == 0 || autobright[dev_nr] == 1)
+	                ? autobright[dev_nr] : W9968CF_AUTOBRIGHT;
+
+	cam->auto_exp = (autoexp[dev_nr] == 0 || autoexp[dev_nr] == 1)
+	                ? autoexp[dev_nr] : W9968CF_AUTOEXP;
+
+	cam->lightfreq = (lightfreq[dev_nr] == 50 || lightfreq[dev_nr] == 60)
+	                 ? lightfreq[dev_nr] : W9968CF_LIGHTFREQ;
+
+	cam->bandfilt = (bandingfilter[dev_nr] == 0 || 
+	                 bandingfilter[dev_nr] == 1)
+	                ? bandingfilter[dev_nr] : W9968CF_BANDINGFILTER;
+
+	cam->backlight = (backlight[dev_nr] == 0 || backlight[dev_nr] == 1)
+	                 ? backlight[dev_nr] : W9968CF_BACKLIGHT;
+
+	cam->clockdiv = (clockdiv[dev_nr] == -1 || clockdiv[dev_nr] >= 0)
+	                ? clockdiv[dev_nr] : W9968CF_CLOCKDIV;
+
+	cam->mirror = (mirror[dev_nr] == 0 || mirror[dev_nr] == 1)
+	              ? mirror[dev_nr] : W9968CF_MIRROR;
+
+	cam->sensor_mono = (sensor_mono[dev_nr]==0 || sensor_mono[dev_nr]==1)
+	                   ? sensor_mono[dev_nr] : W9968CF_SENSOR_MONO;
+
+	cam->picture.brightness = brightness[dev_nr];
+	cam->picture.hue = hue[dev_nr];
+	cam->picture.colour = colour[dev_nr];
+	cam->picture.contrast = contrast[dev_nr];
+	cam->picture.whiteness = whiteness[dev_nr];
+	if (w9968cf_valid_palette(force_palette[dev_nr])) {
+		cam->picture.palette = force_palette[dev_nr];
+		cam->force_palette = 1;
+	} else {
+		cam->force_palette = 0;
+		if (cam->decompression == 0)
+			cam->picture.palette = W9968CF_PALETTE_DECOMP_OFF;
+		else if (cam->decompression == 1)
+			cam->picture.palette = W9968CF_PALETTE_DECOMP_FORCE;
+		else
+			cam->picture.palette = W9968CF_PALETTE_DECOMP_ON;
+	}
+
+	cam->force_rgb = (force_rgb[dev_nr] == 0 || force_rgb[dev_nr] == 1)
+	                 ? force_rgb[dev_nr] : W9968CF_FORCE_RGB;
+
+	cam->window.x = 0;
+	cam->window.y = 0;
+	cam->window.width = W9968CF_WIDTH;
+	cam->window.height = W9968CF_HEIGHT;
+	cam->window.chromakey = 0;
+	cam->window.clipcount = 0;
+	cam->window.flags = 0;
+
+	/* If the video post-processing module is not present, some paramaters
+	   must be overridden: */
+	if (!w9968cf_vppmod_present) {
+		if (cam->decompression == 1)
+			cam->decompression = 2;
+		cam->upscaling = 0;
+		if (cam->picture.palette != VIDEO_PALETTE_UYVY)
+			cam->force_palette = 0;
+		cam->picture.palette = VIDEO_PALETTE_UYVY;
+	}
+
+	cam->picture.depth = w9968cf_valid_depth(cam->picture.palette);
+
+	DBG(3, "%s configured with settings #%d:", 
+	    symbolic(camlist, cam->id), dev_nr)
+	
+	DBG(3, "- Data packet size for USB isochrnous transfer: %d bytes.",
+	    wMaxPacketSize[cam->altsetting-1])
+	
+	DBG(3, "- Number of requested video frame buffers: %d", 
+	    cam->max_buffers)
+
+	if (cam->double_buffer)
+		DBG(3, "- Hardware double buffering enabled.")
+	else 
+		DBG(3, "- Hardware double buffering disabled.")
+
+	if (cam->filter_type == 0)
+		DBG(3, "- Video filtering disabled.")
+	else if (cam->filter_type == 1)
+		DBG(3, "- Video filtering enabled: type 1-2-1.")
+	else if (cam->filter_type == 2)
+		DBG(3, "- Video filtering enabled: type 2-3-6-3-2.")
+
+	if (cam->clamping)
+		DBG(3, "- Video data clamping (CCIR-601 format) enabled.")
+	else
+		DBG(3, "- Video data clamping (CCIR-601 format) disabled.")
+
+	if (cam->largeview)
+		DBG(3, "- Large view enabled.")
+	else
+		DBG(3, "- Large view disabled.")
+
+	if ((cam->decompression) == 0 && (!cam->force_palette))
+		DBG(3, "- Decompression disabled.")
+	else if ((cam->decompression) == 1 && (!cam->force_palette))
+		DBG(3, "- Decompression forced.")
+	else if ((cam->decompression) == 2 && (!cam->force_palette))
+		DBG(3, "- Decompression allowed.")
+
+	if (cam->upscaling)
+		DBG(3, "- Software image scaling enabled.")
+	else
+		DBG(3, "- Software image scaling disabled.")
+
+	if (cam->force_palette)
+		DBG(3, "- Image palette forced to %s.",
+		    symbolic(v4l1_plist, cam->picture.palette))
+
+	if (cam->force_rgb)
+		DBG(3, "- RGB component ordering will be used instead of BGR.")
+
+	if (cam->auto_brt)
+		DBG(3, "- Auto brightness enabled.")
+	else
+		DBG(3, "- Auto brightness disabled.")
+
+	if (cam->auto_exp)
+		DBG(3, "- Auto exposure enabled.")
+	else
+		DBG(3, "- Auto exposure disabled.")
+
+	if (cam->backlight)
+		DBG(3, "- Backlight exposure algorithm enabled.")
+	else
+		DBG(3, "- Backlight exposure algorithm disabled.")
+
+	if (cam->mirror)
+		DBG(3, "- Mirror enabled.")
+	else
+		DBG(3, "- Mirror disabled.")
+
+	if (cam->bandfilt)
+		DBG(3, "- Banding filter enabled.")
+	else
+		DBG(3, "- Banding filter disabled.")
+
+	DBG(3, "- Power lighting frequency: %d", cam->lightfreq)
+
+	if (cam->clockdiv == -1)
+		DBG(3, "- Automatic clock divisor enabled.")
+	else
+		DBG(3, "- Clock divisor: %d", cam->clockdiv)
+
+	if (cam->sensor_mono)
+		DBG(3, "- CMOS sensor used as monochrome.")
+	else
+		DBG(3, "- CMOS sensor not used as monochrome.")
+}
+
+
+/*--------------------------------------------------------------------------
+  Release the resources used by the driver.
+  This function is called on disconnect 
+  (or on close if deallocation has been deferred)
+  --------------------------------------------------------------------------*/
+static void w9968cf_release_resources(struct w9968cf_device* cam)
+{
+	down(&w9968cf_devlist_sem);
+
+	DBG(2, "V4L device deregistered: /dev/video%d", cam->v4ldev.minor)
+
+	w9968cf_proc_destroy_dev(cam);
+	video_unregister_device(&cam->v4ldev);
+	list_del(&cam->v4llist);
+	i2c_del_adapter(&cam->i2c_adapter);
+	w9968cf_deallocate_memory(cam);
+	kfree(cam->control_buffer);
+	kfree(cam->data_buffer);
+
+	up(&w9968cf_devlist_sem);
+
+	DBG(5, "Resources released.")
+}
+
+
+
+/****************************************************************************
+ * Video4Linux interface                                                    *
+ ****************************************************************************/
+
+static int w9968cf_open(struct inode* inode, struct file* filp)
+{
+	struct w9968cf_device* cam =
+	  (struct w9968cf_device*)video_devdata(filp)->priv;    
+	int err;
+
+	down(&cam->dev_sem);
+
+	if (cam->sensor == CC_UNKNOWN) {
+		DBG(2, "No supported CMOS sensor has been detected by the "
+		       "'ovcamchip' module for the %s (/dev/video%d). Make "
+		       "sure it is loaded *before* the 'w9968cf' module.", 
+		    symbolic(camlist, cam->id),cam->v4ldev.minor)
+		up(&cam->dev_sem);
+		return -ENODEV;
+	}
+
+	if (cam->users) {
+		DBG(2, "%s (/dev/video%d) has been already occupied by '%s'.",
+		    symbolic(camlist, cam->id),cam->v4ldev.minor, cam->command)
+		if ((filp->f_flags & O_NONBLOCK)||(filp->f_flags & O_NDELAY)) {
+			up(&cam->dev_sem);
+			return -EWOULDBLOCK;
+		}
+		up(&cam->dev_sem);
+		err = wait_event_interruptible(cam->open, cam->disconnected ||
+		                               (cam->users == 0));
+		if (err)
+			return err;
+		if (cam->disconnected)
+			return -ENODEV;
+		down(&cam->dev_sem);
+	}
+
+	DBG(5, "Opening the %s, /dev/video%d ...",
+	    symbolic(camlist, cam->id), cam->v4ldev.minor)
+
+	cam->streaming = 0;
+	cam->misconfigured = 0;
+
+	if (!w9968cf_vppmod_present)
+		w9968cf_vppmod_detect();
+
+	if ((err = w9968cf_allocate_memory(cam)))
+		goto deallocate_memory;
+
+	if ((err = w9968cf_init_chip(cam)))
+		goto deallocate_memory;
+
+	if ((err = w9968cf_start_transfer(cam)))
+		goto deallocate_memory;
+
+	filp->private_data = (void*)cam;
+
+	cam->users++;
+	strcpy(cam->command, current->comm);
+
+	init_waitqueue_head(&cam->wait_queue);
+
+	up(&cam->dev_sem);
+
+	DBG(5, "Video device is open.")
+	return 0;
+
+deallocate_memory:
+	w9968cf_deallocate_memory(cam);
+	DBG(2, "Failed to open the video device.")
+	up(&cam->dev_sem);
+	return err;
+}
+
+
+static int w9968cf_release(struct inode* inode, struct file* filp)
+{
+	struct w9968cf_device* cam = 
+	  (struct w9968cf_device*)video_devdata(filp)->priv;
+
+	down(&cam->dev_sem); /* prevent disconnect() to be called */
+
+	w9968cf_stop_transfer(cam);
+
+	if (cam->disconnected) {
+		w9968cf_release_resources(cam);
+		up(&cam->dev_sem);
+		kfree(cam);
+		return 0;
+	}
+
+	cam->users--;
+	w9968cf_deallocate_memory(cam);
+
+	if (waitqueue_active(&cam->open))
+		wake_up_interruptible(&cam->open);
+
+	DBG(5, "Video device closed.")
+	up(&cam->dev_sem);
+	return 0;
+}
+
+
+static ssize_t
+w9968cf_read(struct file* filp, char* buf, size_t count, loff_t* f_pos)
+{
+	struct w9968cf_device* cam =
+	  (struct w9968cf_device*)video_devdata(filp)->priv;
+	struct w9968cf_frame_t* fr;
+	int err = 0;
+
+	if (filp->f_flags & O_NONBLOCK)
+		return -EWOULDBLOCK;
+
+	if (down_interruptible(&cam->fileop_sem))
+		return -ERESTARTSYS;
+
+	if (cam->disconnected) {
+		DBG(2, "Device not present.")
+		up(&cam->fileop_sem);
+		return -ENODEV;
+	}
+
+	if (cam->misconfigured) {
+		DBG(2, "The camera is misconfigured. Close and open it again.")
+		up(&cam->fileop_sem);
+		return -EIO;
+	}
+
+	if (!cam->frame[0].queued)
+		w9968cf_push_frame(cam, 0);
+
+	if (!cam->frame[1].queued)
+		w9968cf_push_frame(cam, 1);
+
+	err = wait_event_interruptible(cam->wait_queue,
+	                               cam->frame[0].status == F_READY ||
+	                               cam->frame[1].status == F_READY ||
+	                               cam->disconnected);
+	if (err) {
+		up(&cam->fileop_sem);
+		return err;
+	}
+	if (cam->disconnected) {
+		up(&cam->fileop_sem);
+		return -ENODEV;
+	}
+
+	fr = (cam->frame[0].status == F_READY) ? &cam->frame[0]:&cam->frame[1];
+
+	if (w9968cf_vppmod_present)
+		w9968cf_postprocess_frame(cam, fr);
+
+	if (count > fr->length)
+		count = fr->length;
+
+	if (copy_to_user(buf, fr->buffer, count)) {
+		fr->status = F_UNUSED;
+		up(&cam->fileop_sem);
+		return -EFAULT;
+	}
+	*f_pos += count;
+
+	fr->status = F_UNUSED;
+
+	DBG(5, "%d bytes read.", count)
+
+	up(&cam->fileop_sem);
+	return count;
+}
+
+
+static int w9968cf_mmap(struct file* filp, struct vm_area_struct *vma)
+{
+	struct w9968cf_device* cam =
+	  (struct w9968cf_device*)video_devdata(filp)->priv;
+
+	unsigned long vsize = vma->vm_end - vma->vm_start,
+	              psize = cam->nbuffers * w9968cf_get_max_bufsize(cam),
+	              start = vma->vm_start,
+	              pos = (unsigned long)cam->frame[0].buffer,
+	              page;
+
+	if (cam->disconnected) {
+		DBG(2, "Device not present.")
+		return -ENODEV;
+	}
+
+	if (cam->misconfigured) {
+		DBG(2, "The camera is misconfigured. Close and open it again.")
+		return -EIO;
+	}
+
+	PDBGG("mmapping %li bytes...", vsize)
+
+        if (vsize > psize - (vma->vm_pgoff << PAGE_SHIFT))
+		return -EAGAIN;
+
+	while (vsize > 0) {
+		page = kvirt_to_pa(pos) + vma->vm_pgoff;
+		if(remap_page_range(start, page, PAGE_SIZE, vma->vm_page_prot))
+			return -EAGAIN;
+		start += PAGE_SIZE;
+		pos += PAGE_SIZE;
+		vsize = (vsize > PAGE_SIZE) ? vsize-PAGE_SIZE : 0;
+	}
+
+	DBG(5, "mmap method successfully called.")
+	return 0;
+}
+
+
+static int
+w9968cf_ioctl(struct inode* inode, struct file* filp,
+              unsigned int cmd, unsigned long arg)
+{
+	struct w9968cf_device* cam =
+	  (struct w9968cf_device*)video_devdata(filp)->priv;
+	int err;
+
+	if (down_interruptible(&cam->fileop_sem))
+		return -ERESTARTSYS;
+
+	if (cam->disconnected) {
+		DBG(2, "Device not present.")
+		up(&cam->fileop_sem);
+		return -ENODEV;
+	}
+
+	if (cam->misconfigured) {
+		DBG(2, "The camera is misconfigured. Close and open it again.")
+		up(&cam->fileop_sem);
+		return -EIO;
+	}
+
+	err = w9968cf_do_ioctl(cam, cmd, (void*)arg);
+
+	up(&cam->fileop_sem);
+	return err;
+}
+
+
+static int 
+w9968cf_do_ioctl(struct w9968cf_device* cam, unsigned cmd, void* arg)
+{
+	const char* v4l1_ioctls[] = {
+		"?", "CGAP", "GCHAN", "SCHAN", "GTUNER", "STUNER", 
+		"GPICT", "SPICT", "CCAPTURE", "GWIN", "SWIN", "GFBUF",
+		"SFBUF", "KEY", "GFREQ", "SFREQ", "GAUDIO", "SAUDIO",
+		"SYNC", "MCAPTURE", "GMBUF", "GUNIT", "GCAPTURE", "SCAPTURE",
+		"SPLAYMODE", "SWRITEMODE", "GPLAYINFO", "SMICROCODE", 
+		"GVBIFMT", "SVBIFMT" 
+	};
+
+	#define V4L1_IOCTL(cmd) \
+	        ((_IOC_NR((cmd)) < sizeof(v4l1_ioctls)/sizeof(char*)) ? \
+	        v4l1_ioctls[_IOC_NR((cmd))] : "???")
+
+	switch (cmd) {
+
+	case VIDIOCGCAP: /* get video capability */
+	{
+		struct video_capability cap = {
+			.type = VID_TYPE_CAPTURE | VID_TYPE_SCALES,
+			.channels = 1,
+			.audios = 0,
+			.minwidth = cam->minwidth,
+			.minheight = cam->minheight,
+		};
+		sprintf(cap.name, "W996[87]CF USB Camera #%d", 
+		        cam->v4ldev.minor);
+		cap.maxwidth = (cam->upscaling && w9968cf_vppmod_present)
+		               ? W9968CF_MAX_WIDTH : cam->maxwidth;
+		cap.maxheight = (cam->upscaling && w9968cf_vppmod_present)
+		                ? W9968CF_MAX_HEIGHT : cam->maxheight;
+
+		if (copy_to_user(arg, &cap, sizeof(cap)))
+			return -EFAULT;
+
+		DBG(5, "VIDIOCGCAP successfully called.")
+		return 0;
+	}
+
+	case VIDIOCGCHAN: /* get video channel informations */
+	{
+		struct video_channel chan;
+		if (copy_from_user(&chan, arg, sizeof(chan)))
+			return -EFAULT;
+
+		if (chan.channel != 0)
+			return -EINVAL;
+
+		strcpy(chan.name, "Camera");
+		chan.tuners = 0;
+		chan.flags = 0;
+		chan.type = VIDEO_TYPE_CAMERA;
+		chan.norm = VIDEO_MODE_AUTO;
+
+		if (copy_to_user(arg, &chan, sizeof(chan)))
+			return -EFAULT;
+
+		DBG(5, "VIDIOCGCHAN successfully called.")
+		return 0;
+	}
+
+	case VIDIOCSCHAN: /* set active channel */
+	{
+		struct video_channel chan;
+
+		if (copy_from_user(&chan, arg, sizeof(chan)))
+			return -EFAULT;
+
+		if (chan.channel != 0)
+			return -EINVAL;
+
+		DBG(5, "VIDIOCSCHAN successfully called.")
+		return 0;
+	}
+
+	case VIDIOCGPICT: /* get image properties of the picture */
+	{
+		struct video_picture pict;
+
+		if (w9968cf_sensor_get_picture(cam, &pict))
+			return -EIO;
+
+		pict.depth = cam->picture.depth;
+		pict.palette = cam->picture.palette;
+
+		if (copy_to_user(arg, &pict, sizeof(pict)))
+			return -EFAULT;
+
+		DBG(5, "VIDIOCGPICT successfully called.")
+		return 0;
+	}
+
+	case VIDIOCSPICT: /* change picture settings */
+	{
+		struct video_picture pict;
+		int err = 0;
+
+		if (copy_from_user(&pict, arg, sizeof(pict)))
+			return -EFAULT;
+
+		if ( (cam->force_palette || !w9968cf_vppmod_present) 
+		     && pict.palette != cam->picture.palette ) {
+			DBG(4, "Palette %s rejected. Only %s is allowed.",
+			    symbolic(v4l1_plist, pict.palette),
+			    symbolic(v4l1_plist, cam->picture.palette))
+			return -EINVAL;
+		}
+
+		if (!w9968cf_valid_palette(pict.palette)) {
+			DBG(4, "Palette %s not supported. VIDIOCSPICT failed.",
+			    symbolic(v4l1_plist, pict.palette))
+			return -EINVAL;
+		}
+
+		if (pict.depth != w9968cf_valid_depth(pict.palette)) {
+			DBG(4, "Depth %d bpp is not supported for %s palette. "
+			       "VIDIOCSPICT failed.", 
+			    pict.depth, symbolic(v4l1_plist, pict.palette))
+			return -EINVAL;
+		}
+
+		if (!cam->force_palette) {
+		   if (cam->decompression == 0) {
+		      if (w9968cf_need_decompression(pict.palette)) {
+		         DBG(4, "Decompression disabled: palette %s is not "
+		                "allowed. VIDIOCSPICT failed.",
+		             symbolic(v4l1_plist, pict.palette))
+		         return -EINVAL;
+		      }
+		   } else if (cam->decompression == 1) {
+		      if (!w9968cf_need_decompression(pict.palette)) {
+		         DBG(4, "Decompression forced: palette %s is not "
+		                "allowed. VIDIOCSPICT failed.",
+		             symbolic(v4l1_plist, pict.palette))
+		         return -EINVAL;
+		      }
+		   }
+		}
+
+		if (pict.palette != cam->picture.palette ||
+		    pict.depth   != cam->picture.depth)
+		{
+			if(*cam->requested_frame
+			   || cam->frame_current->queued) {
+				err = wait_event_interruptible
+				      ( cam->wait_queue,
+				        cam->disconnected ||
+				        (!*cam->requested_frame &&
+				         !cam->frame_current->queued) );
+				if (err)
+					return err;
+				if (cam->disconnected)
+					return -ENODEV;
+			}
+
+			if (w9968cf_stop_transfer(cam))
+				goto ioctl_fail;
+
+			if (w9968cf_set_picture(cam, pict))
+				goto ioctl_fail;
+
+			if (w9968cf_start_transfer(cam))
+				goto ioctl_fail;
+
+		} else if ( ((pict.brightness != cam->picture.brightness) &&
+		            (!cam->auto_brt)) ||
+		            pict.hue != cam->picture.hue ||
+		            pict.colour != cam->picture.colour ||
+		            pict.contrast != cam->picture.contrast ||
+		            pict.whiteness != cam->picture.whiteness ) {
+			if (w9968cf_sensor_set_picture(cam, pict))
+				return -EIO;
+		}
+
+		DBG(5, "VIDIOCSPICT successfully called.")
+		return 0;
+	}
+
+	case VIDIOCSWIN: /* set capture area */
+	{
+		struct video_window win;
+		int err = 0;
+
+		if (copy_from_user(&win, arg, sizeof(win)))
+			return -EFAULT;
+
+		DBG(6, "VIDIOCSWIN called: clipcount=%d, flags=%d, "
+		       "x=%d, y=%d, %dx%d", win.clipcount, win.flags,
+		    win.x, win.y, win.width, win.height)
+
+		if (win.clipcount != 0 || win.flags != 0)
+			return -EINVAL;
+
+		if ((err = w9968cf_adjust_window_size(cam, (u16*)&win.width,
+		                                      (u16*)&win.height))) {
+			DBG(4, "Resolution not supported (%dx%d)."
+			       "VIDIOCSWIN failed.", win.width, win.height)
+			return err;
+		}
+
+		if (win.x != cam->window.x ||
+		    win.y != cam->window.y ||
+		    win.width != cam->window.width ||
+		    win.height != cam->window.height) {
+
+			if(*cam->requested_frame
+			   || cam->frame_current->queued) {
+				err = wait_event_interruptible
+				      ( cam->wait_queue,
+				        cam->disconnected ||
+				        (!*cam->requested_frame &&
+				         !cam->frame_current->queued) );
+				if (err)
+					return err;
+				if (cam->disconnected)
+					return -ENODEV;
+			}
+
+			if (w9968cf_stop_transfer(cam))
+				goto ioctl_fail;
+
+			/* This _must_ be called before set_window() */
+			if (w9968cf_set_picture(cam, cam->picture))
+				goto ioctl_fail;
+
+			if (w9968cf_set_window(cam, win))
+				goto ioctl_fail;
+
+			if (w9968cf_start_transfer(cam))
+				goto ioctl_fail;
+		}
+
+		DBG(5, "VIDIOCSWIN successfully called. ")
+		return 0;
+	}
+
+	case VIDIOCGWIN: /* get current window properties */
+	{
+		if (copy_to_user(arg,&cam->window,sizeof(struct video_window)))
+			return -EFAULT;
+
+		DBG(5, "VIDIOCGWIN successfully called.")
+		return 0;
+	}
+
+	case VIDIOCGMBUF: /* request for memory (mapped) buffer */
+	{
+		struct video_mbuf mbuf;
+		u8 i;
+
+		mbuf.size = cam->nbuffers * w9968cf_get_max_bufsize(cam);
+		mbuf.frames = cam->nbuffers;
+		for (i = 0; i < cam->nbuffers; i++)
+			mbuf.offsets[i] = (unsigned long)cam->frame[i].buffer -
+			                  (unsigned long)cam->frame[0].buffer;
+
+		if (copy_to_user(arg, &mbuf, sizeof(mbuf)))
+			return -EFAULT;
+
+		DBG(5, "VIDIOCGMBUF successfully called.")
+		return 0;
+	}
+
+	case VIDIOCMCAPTURE: /* start the capture to a frame */
+	{
+		struct video_mmap mmap;
+		struct w9968cf_frame_t* fr;
+		int err = 0;
+
+		if (copy_from_user(&mmap, arg, sizeof(mmap)))
+			return -EFAULT;
+
+		DBG(6, "VIDIOCMCAPTURE called: frame #%d, format=%s, %dx%d",
+		    mmap.frame, symbolic(v4l1_plist, mmap.format), 
+		    mmap.width, mmap.height)
+
+		if (mmap.frame >= cam->nbuffers) {
+			DBG(4, "Invalid frame number (%d). "
+			       "VIDIOCMCAPTURE failed.", mmap.frame)
+			return -EINVAL;
+		}
+
+		if (mmap.format!=cam->picture.palette && 
+		    (cam->force_palette || !w9968cf_vppmod_present)) {
+			DBG(4, "Palette %s rejected. Only %s is allowed.",
+			    symbolic(v4l1_plist, mmap.format),
+			    symbolic(v4l1_plist, cam->picture.palette))
+			return -EINVAL;
+		}
+
+		if (!w9968cf_valid_palette(mmap.format)) {
+			DBG(4, "Palette %s not supported. "
+			       "VIDIOCMCAPTURE failed.", 
+			    symbolic(v4l1_plist, mmap.format))
+			return -EINVAL;
+		}
+
+		if (!cam->force_palette) {
+		   if (cam->decompression == 0) {
+		      if (w9968cf_need_decompression(mmap.format)) {
+		         DBG(4, "Decompression disabled: palette %s is not "
+		                "allowed. VIDIOCSPICT failed.",
+		             symbolic(v4l1_plist, mmap.format))
+		         return -EINVAL;
+		      }
+		   } else if (cam->decompression == 1) {
+		      if (!w9968cf_need_decompression(mmap.format)) {
+		         DBG(4, "Decompression forced: palette %s is not "
+		                "allowed. VIDIOCSPICT failed.",
+		             symbolic(v4l1_plist, mmap.format))
+		         return -EINVAL;
+		      }
+		   }
+		}
+
+		if (w9968cf_adjust_window_size(cam, (u16*)&mmap.width, 
+		                               (u16*)&mmap.height)) {
+			DBG(4, "Resolution not supported (%dx%d). "
+			       "VIDIOCMCAPTURE failed.",
+			    mmap.width, mmap.height)
+			return -EINVAL;
+		}
+
+		fr = &cam->frame[mmap.frame];
+
+		if (mmap.width  != cam->window.width ||
+		    mmap.height != cam->window.height ||
+		    mmap.format != cam->picture.palette) {
+
+			struct video_window win;
+			struct video_picture pict;
+
+			if(*cam->requested_frame
+			   || cam->frame_current->queued) {
+				DBG(6, "VIDIOCMCAPTURE. Change settings for "
+				       "frame #%d: %dx%d, format %s. Wait...",
+				    mmap.frame, mmap.width, mmap.height,
+			            symbolic(v4l1_plist, mmap.format))
+				err = wait_event_interruptible
+				      ( cam->wait_queue,
+				        cam->disconnected ||
+				        (!*cam->requested_frame &&
+				         !cam->frame_current->queued) );
+				if (err)
+					return err;
+				if (cam->disconnected)
+					return -ENODEV;
+			}
+
+			memcpy(&win, &cam->window, sizeof(win));
+			memcpy(&pict, &cam->picture, sizeof(pict));
+			win.width = mmap.width;
+			win.height = mmap.height;
+			pict.palette = mmap.format;
+
+			if (w9968cf_stop_transfer(cam))
+				goto ioctl_fail;
+
+			/* This before set_window */
+			if (w9968cf_set_picture(cam, pict)) 
+				goto ioctl_fail;
+
+			if (w9968cf_set_window(cam, win))
+				goto ioctl_fail;
+
+			if (w9968cf_start_transfer(cam))
+				goto ioctl_fail;
+
+		} else 	if (fr->queued) {
+
+			DBG(6, "Wait until frame #%d is free.", mmap.frame)
+			
+			err = wait_event_interruptible(cam->wait_queue, 
+			                               cam->disconnected ||
+			                               (!fr->queued));
+			if (err)
+				return err;
+			if (cam->disconnected)
+				return -ENODEV;
+		}
+
+		w9968cf_push_frame(cam, mmap.frame);
+		DBG(5, "VIDIOCMCAPTURE(%d): successfully called.", mmap.frame)
+		return 0;
+	}
+
+	case VIDIOCSYNC: /* wait until the capture of a frame is finished */
+	{
+		unsigned int f_num = *((unsigned int *) arg);
+		struct w9968cf_frame_t* fr;
+		int err = 0;
+
+		if (f_num >= cam->nbuffers) {
+			DBG(4, "Invalid frame number (%d). "
+			       "VIDIOCMCAPTURE failed.", f_num)
+			return -EINVAL;
+		}
+
+		DBG(6, "VIDIOCSYNC called for frame #%d", f_num)
+
+		fr = &cam->frame[f_num];
+
+		switch (fr->status) {
+		case F_UNUSED:
+			if (!fr->queued) {
+				DBG(4, "VIDIOSYNC: Frame #%d not requested!",
+				    f_num)
+				return -EFAULT;
+			}
+		case F_ERROR:
+		case F_GRABBING:
+			err = wait_event_interruptible(cam->wait_queue, 
+			                               (fr->status == F_READY)
+			                               || cam->disconnected);
+			if (err)
+				return err;
+			if (cam->disconnected)
+				return -ENODEV;
+			break;
+		case F_READY:
+			break;
+		}
+
+		if (w9968cf_vppmod_present)
+			w9968cf_postprocess_frame(cam, fr);
+
+		fr->status = F_UNUSED;
+
+		DBG(5, "VIDIOCSYNC(%d) successfully called.", f_num)
+		return 0;
+	}
+
+	case VIDIOCGUNIT:/* report the unit numbers of the associated devices*/
+	{
+		struct video_unit unit = {
+			.video = cam->v4ldev.minor,
+			.vbi = VIDEO_NO_UNIT,
+			.radio = VIDEO_NO_UNIT,
+			.audio = VIDEO_NO_UNIT,
+			.teletext = VIDEO_NO_UNIT,
+		};
+
+		if (copy_to_user(arg, &unit, sizeof(unit)))
+			return -EFAULT;
+
+		DBG(5, "VIDIOCGUNIT successfully called.")
+		return 0;
+	}
+
+	case VIDIOCKEY:
+		return 0;
+
+	case VIDIOCGFBUF:
+	{
+		struct video_buffer* buffer = (struct video_buffer*)arg;
+
+		memset(buffer, 0, sizeof(struct video_buffer));
+
+		DBG(5, "VIDIOCGFBUF successfully called.")
+		return 0;
+	}
+
+	case VIDIOCGTUNER:
+	{
+		struct video_tuner tuner;
+		if (copy_from_user(&tuner, arg, sizeof(tuner)))
+			return -EFAULT;
+
+		if (tuner.tuner != 0);
+			return -EINVAL;
+
+		strcpy(tuner.name, "no_tuner");
+		tuner.rangelow = 0;
+		tuner.rangehigh = 0;
+		tuner.flags = VIDEO_TUNER_NORM;
+		tuner.mode = VIDEO_MODE_AUTO;
+		tuner.signal = 0xffff;
+
+		if (copy_to_user(arg, &tuner, sizeof(tuner)))
+			return -EFAULT;
+
+		DBG(5, "VIDIOCGTUNER successfully called.")
+		return 0;
+	}
+
+	case VIDIOCSTUNER:
+	{
+		struct video_tuner tuner;
+		if (copy_from_user(&tuner, arg, sizeof(tuner)))
+			return -EFAULT;
+
+		if (tuner.tuner != 0)
+			return -EINVAL;
+
+		if (tuner.mode != VIDEO_MODE_AUTO)
+			return -EINVAL;
+
+		DBG(5, "VIDIOCSTUNER successfully called.")
+		return 0;
+	}
+
+	case VIDIOCSFBUF:
+	case VIDIOCCAPTURE:
+	case VIDIOCGFREQ:
+	case VIDIOCSFREQ:
+	case VIDIOCGAUDIO:
+	case VIDIOCSAUDIO:
+	case VIDIOCSPLAYMODE:
+	case VIDIOCSWRITEMODE:
+	case VIDIOCGPLAYINFO:
+	case VIDIOCSMICROCODE:
+	case VIDIOCGVBIFMT:
+	case VIDIOCSVBIFMT:
+		DBG(4, "Unsupported V4L1 IOCtl: VIDIOC%s "
+		       "(type 0x%01X, "
+		       "n. 0x%01X, "
+		       "dir. 0x%01X, " 
+		       "size 0x%02X).",
+		    V4L1_IOCTL(cmd),
+		    _IOC_TYPE(cmd),_IOC_NR(cmd),_IOC_DIR(cmd),_IOC_SIZE(cmd))
+
+		return -EINVAL;
+
+	default:
+		DBG(4, "Invalid V4L1 IOCtl: VIDIOC%s "
+		       "type 0x%01X, "
+		       "n. 0x%01X, "
+		       "dir. 0x%01X, "
+		       "size 0x%02X.",
+		    V4L1_IOCTL(cmd),
+		    _IOC_TYPE(cmd),_IOC_NR(cmd),_IOC_DIR(cmd),_IOC_SIZE(cmd))
+
+		return -ENOIOCTLCMD;
+
+	} /* end of switch */
+
+ioctl_fail:
+	cam->misconfigured = 1;
+	DBG(1, "VIDIOC%s failed because of hardware problems. "
+	       "To use the camera, close and open it again.", V4L1_IOCTL(cmd))
+	return -EFAULT;
+}
+
+
+static struct file_operations w9968cf_fops = {
+	.owner =   THIS_MODULE,
+	.open =    w9968cf_open,
+	.release = w9968cf_release,
+	.read =    w9968cf_read,
+	.ioctl =   w9968cf_ioctl,
+	.mmap =    w9968cf_mmap,
+	.llseek =  no_llseek,
+};
+
+
+
+/****************************************************************************
+ * USB probe and V4L registration, disconnect and id_table[] definition     *
+ ****************************************************************************/
+
+static void*
+w9968cf_usb_probe(struct usb_device* udev,
+                  unsigned int ifnum, const struct usb_device_id* id)
+{
+	struct w9968cf_device* cam;
+	int err = 0;
+	enum w9968cf_model_id mod_id;
+	struct list_head* ptr;
+	u8 sc = 0; /* number of simultaneous cameras */
+	static unsigned short dev_nr = 0; /* we are handling device number n */
+
+	if (udev->descriptor.idVendor  == winbond_id_table[0].idVendor &&
+	    udev->descriptor.idProduct == winbond_id_table[0].idProduct)
+		mod_id = W9968CF_MOD_CLVBWGP; /* see camlist[] table */
+
+	else if (udev->descriptor.idVendor  == winbond_id_table[1].idVendor &&
+	         udev->descriptor.idProduct == winbond_id_table[1].idProduct)
+		mod_id = W9968CF_MOD_GENERIC; /* see camlist[] table */
+
+	else
+		return NULL;
+
+	/* We don't handle multi-config cameras */
+	if (udev->descriptor.bNumConfigurations != 1)
+		return NULL;
+
+	DBG(2, "%s detected.", symbolic(camlist, mod_id))
+
+	if (simcams > W9968CF_MAX_DEVICES)
+		simcams = W9968CF_SIMCAMS;
+
+	/* How many cameras are connected ? */
+	down(&w9968cf_devlist_sem);
+	list_for_each(ptr, &w9968cf_dev_list)
+		sc++;
+	up(&w9968cf_devlist_sem);
+
+	if (sc >= simcams) {
+		DBG(2, "Device rejected: too many connected cameras "
+		       "(max. %d)", simcams)
+		return NULL;
+	}
+
+	err = usb_set_configuration(udev, 1);
+	err += usb_set_interface(udev, 0, 0);
+
+	if (err) {
+		DBG(1, "Device configuration failed.")
+		return NULL;
+	}
+
+	cam = (struct w9968cf_device*)
+	          kmalloc(sizeof(struct w9968cf_device), GFP_KERNEL);
+
+	if (!cam) {
+		DBG(1, "Couldn't allocate %d bytes of kernel memory.",
+		    sizeof(struct w9968cf_device))
+		err = -ENOMEM;
+		goto fail;
+	}
+	memset(cam, 0, sizeof(*cam));
+
+	init_MUTEX(&cam->dev_sem);
+	down(&cam->dev_sem);
+
+	/* Allocate 2 bytes of memory for camera control USB transfers */
+	if (!(cam->control_buffer = (u16*)kmalloc(2, GFP_KERNEL))) {
+		DBG(1,"Couldn't allocate memory for camera control transfers.")
+		err = -ENOMEM;
+		goto fail;
+	}
+	memset(cam->control_buffer, 0, 2);
+
+	/* Allocate 8 bytes of memory for USB data transfers to the FSB */
+	if (!(cam->data_buffer = (u16*)kmalloc(8, GFP_KERNEL))) {
+		DBG(1, "Couldn't allocate memory for data "
+		       "transfers to the FSB.")
+		err = -ENOMEM;
+		goto fail;
+	}
+	memset(cam->data_buffer, 0, 8);
+
+	/* Set some basic constants */
+	w9968cf_configure_camera(cam, udev, mod_id, dev_nr);
+
+	err = video_register_device(&cam->v4ldev, VFL_TYPE_GRABBER,
+	                            video_nr[dev_nr]);
+	if (err) {
+		DBG(1, "V4L device registration failed.")
+		if (err == -ENFILE && video_nr[dev_nr] == -1)
+			DBG(2, "Couldn't find a free /dev/videoX node.")
+		video_nr[dev_nr] = -1;
+		dev_nr = (dev_nr < W9968CF_MAX_DEVICES-1) ? dev_nr+1 : 0;
+		goto fail;
+	}
+
+	DBG(2, "V4L device registered as /dev/video%d", cam->v4ldev.minor)
+
+	/* Ok, add a new entry into the list of V4L registered devices */
+	down(&w9968cf_devlist_sem);
+	list_add(&cam->v4llist, &w9968cf_dev_list);
+	up(&w9968cf_devlist_sem);
+
+	dev_nr = (dev_nr < W9968CF_MAX_DEVICES-1) ? dev_nr+1 : 0;
+
+	w9968cf_turn_on_led(cam);
+
+	w9968cf_i2c_init(cam);
+
+	w9968cf_proc_create_dev(cam);
+
+	up(&cam->dev_sem);
+	return (void*)cam;
+
+fail: /* Free unused memory */
+	if (cam) {
+		if (cam->control_buffer)
+			kfree(cam->control_buffer);
+		if (cam->data_buffer)
+			kfree(cam->data_buffer);
+		up(&cam->dev_sem);
+		kfree(cam);
+	}
+	return NULL;
+}
+
+
+static void w9968cf_usb_disconnect(struct usb_device* udev, void* drv_context)
+{
+	struct w9968cf_device* cam = (struct w9968cf_device*)drv_context;
+
+	if (cam) {
+		/* Prevent concurrent accesses to data */
+		down(&cam->dev_sem); 
+
+		cam->streaming = 0;
+		cam->disconnected = 1;
+
+		DBG(2, "Disconnecting %s...", symbolic(camlist, cam->id))
+
+		if (waitqueue_active(&cam->open))
+			wake_up_interruptible(&cam->open);
+
+		if (cam->users) {
+			DBG(2, "The device is open (/dev/video%d)! "
+			       "Process name: %s. Deregistration and memory "
+			       "deallocation are deferred on close.",
+			    cam->v4ldev.minor, cam->command)
+
+			cam->misconfigured = 1;
+
+			if (waitqueue_active(&cam->wait_queue))
+				wake_up_interruptible(&cam->wait_queue);
+		} else
+			w9968cf_release_resources(cam);
+
+		up(&cam->dev_sem);
+
+		if (!cam->users)
+			kfree(cam);
+	}
+}
+
+
+static struct usb_driver w9968cf_usb_driver = {
+	.owner =      THIS_MODULE,
+	.name =       "w9968cf",
+	.id_table =   winbond_id_table,
+	.probe =      w9968cf_usb_probe,
+	.disconnect = w9968cf_usb_disconnect,
+};
+
+
+
+/****************************************************************************
+ * Module init, exit and intermodule communication                          *
+ ****************************************************************************/
+
+static int w9968cf_vppmod_detect(void)
+{
+	w9968cf_vpp_init_decoder = inter_module_get("w9968cf_init_decoder");
+
+	if (!w9968cf_vpp_init_decoder) {
+		if (vppmod_load)
+			w9968cf_vpp_init_decoder = inter_module_get_request
+		                                  ( "w9968cf_init_decoder",
+			                            "w9968cf-vpp" );
+		if (!w9968cf_vpp_init_decoder) {
+			w9968cf_vppmod_present = 0;
+			DBG(4, "Video post-processing module not detected.")
+			return -ENODEV;
+		}
+	}
+
+	w9968cf_vpp_check_headers = inter_module_get("w9968cf_check_headers");
+	w9968cf_vpp_decode = inter_module_get("w9968cf_decode");
+	w9968cf_vpp_swap_yuvbytes = inter_module_get("w9968cf_swap_yuvbytes");
+	w9968cf_vpp_uyvy_to_rgbx = inter_module_get("w9968cf_uyvy_to_rgbx");
+	w9968cf_vpp_scale_up = inter_module_get("w9968cf_scale_up");
+
+	w9968cf_vppmod_present = 1;
+
+	/* Initialization */
+	(*w9968cf_vpp_init_decoder)();
+
+	DBG(2, "Video post-processing module detected.")
+	return 0;
+}
+
+
+static void w9968cf_vppmod_release(void)
+{
+	inter_module_put("w9968cf_init_decoder");
+	inter_module_put("w9968cf_check_headers");
+	inter_module_put("w9968cf_decode");
+	inter_module_put("w9968cf_swap_yuvbytes");
+	inter_module_put("w9968cf_uyvy_to_rgbx");
+	inter_module_put("w9968cf_scale_up");
+
+	DBG(2, "Video post-processing module released.")
+}
+
+
+static int __init w9968cf_module_init(void)
+{
+	int err;
+
+	DBG(2, W9968CF_MODULE_NAME" "W9968CF_MODULE_VERSION)
+	DBG(3, W9968CF_MODULE_AUTHOR)
+
+	init_MUTEX(&w9968cf_devlist_sem);
+
+	w9968cf_proc_create();
+
+	w9968cf_vppmod_detect();
+
+	if ((err = usb_register(&w9968cf_usb_driver))) {
+		if (w9968cf_vppmod_present)
+			w9968cf_vppmod_release();
+		w9968cf_proc_destroy();
+		return err;
+	}
+
+	return 0;
+}
+
+
+static void __exit w9968cf_module_exit(void)
+{
+	/* w9968cf_usb_disconnect() will be called */
+	usb_deregister(&w9968cf_usb_driver);
+
+	w9968cf_proc_destroy();	
+
+	if (w9968cf_vppmod_present)
+		w9968cf_vppmod_release();
+
+	DBG(2, W9968CF_MODULE_NAME" deregistered.")
+}
+
+
+module_init(w9968cf_module_init);
+module_exit(w9968cf_module_exit);

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)