|  | 
 |                    W996[87]CF JPEG USB Dual Mode Camera Chip  | 
 |                      Driver for Linux 2.6 (basic version) | 
 |                    ========================================= | 
 |  | 
 |                                - Documentation - | 
 |  | 
 |  | 
 | Index | 
 | ===== | 
 | 1.  Copyright | 
 | 2.  Disclaimer | 
 | 3.  License | 
 | 4.  Overview | 
 | 5.  Supported devices | 
 | 6.  Module dependencies | 
 | 7.  Module loading | 
 | 8.  Module paramaters | 
 | 9.  Contact information | 
 | 10. Credits | 
 |  | 
 |  | 
 | 1. Copyright | 
 | ============ | 
 | Copyright (C) 2002-2004 by Luca Risolia <[email protected]> | 
 |  | 
 |  | 
 | 2. Disclaimer | 
 | ============= | 
 | Winbond is a trademark of Winbond Electronics Corporation. | 
 | This software is not sponsored or developed by Winbond. | 
 |  | 
 |  | 
 | 3. License | 
 | ========== | 
 | 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. | 
 |  | 
 |  | 
 | 4. Overview | 
 | =========== | 
 | This driver supports the video streaming capabilities of the devices mounting | 
 | Winbond W9967CF and Winbond W9968CF JPEG USB Dual Mode Camera Chips. OV681 | 
 | based cameras should be supported as well. | 
 |  | 
 | The driver is divided into two modules: the basic one, "w9968cf", is needed for | 
 | the supported devices to work; the second one, "w9968cf-vpp", is an optional | 
 | module, which provides some useful video post-processing functions like video | 
 | decoding, up-scaling and colour conversions. Once the driver is installed, | 
 | every time an application tries to open a recognized device, "w9968cf" checks | 
 | the presence of the "w9968cf-vpp" module and loads it automatically by default. | 
 |  | 
 | Please keep in mind that official kernels do not include the second module for | 
 | performance purposes. However it is always recommended to download and install | 
 | the latest and complete release of the driver, replacing the existing one, if | 
 | present: it will be still even possible not to load the "w9968cf-vpp" module at | 
 | all, if you ever want to. Another important missing feature of the version in | 
 | the official Linux 2.4 kernels is the writeable /proc filesystem interface. | 
 |  | 
 | The latest and full-featured version of the W996[87]CF driver can be found at: | 
 | http://www.linux-projects.org. Please refer to the documentation included in | 
 | that package, if you are going to use it. | 
 |  | 
 | Up to 32 cameras can be handled at the same time. They can be connected and | 
 | disconnected from the host many times without turning off the computer, if | 
 | your system supports the hotplug facility. | 
 |  | 
 | To change the default settings for each camera, many parameters can be passed | 
 | through command line when the module is loaded into memory. | 
 |  | 
 | The driver relies on the Video4Linux, USB and I2C core modules. It has been | 
 | designed to run properly on SMP systems as well. An additional module, | 
 | "ovcamchip", is mandatory; it provides support for some OmniVision image | 
 | sensors connected to the W996[87]CF chips; if found in the system, the module | 
 | will be automatically loaded by default (provided that the kernel has been | 
 | compiled with the automatic module loading option). | 
 |  | 
 |  | 
 | 5. Supported devices | 
 | ==================== | 
 | At the moment, known W996[87]CF and OV681 based devices are: | 
 | - Aroma Digi Pen VGA Dual Mode ADG-5000 (unknown image sensor) | 
 | - AVerMedia AVerTV USB (SAA7111A, Philips FI1216Mk2 tuner, PT2313L audio chip) | 
 | - Creative Labs Video Blaster WebCam Go (OmniVision OV7610 sensor) | 
 | - Creative Labs Video Blaster WebCam Go Plus (OmniVision OV7620 sensor) | 
 | - Lebon LDC-035A (unknown image sensor) | 
 | - Ezonics EZ-802 EZMega Cam (OmniVision OV8610C sensor) | 
 | - OmniVision OV8610-EDE (OmniVision OV8610 sensor) | 
 | - OPCOM Digi Pen VGA Dual Mode Pen Camera (unknown image sensor) | 
 | - Pretec Digi Pen-II (OmniVision OV7620 sensor) | 
 | - Pretec DigiPen-480 (OmniVision OV8610 sensor) | 
 |  | 
 | If you know any other W996[87]CF or OV681 based cameras, please contact me. | 
 |  | 
 | The list above does not imply that all those devices work with this driver: up | 
 | until now only webcams that have an image sensor supported by the "ovcamchip" | 
 | module work. Kernel messages will always tell you whether this is case. | 
 |  | 
 | Possible external microcontrollers of those webcams are not supported: this | 
 | means that still images cannot be downloaded from the device memory. | 
 |  | 
 | Furthermore, it's worth to note that I was only able to run tests on my | 
 | "Creative Labs Video Blaster WebCam Go". Donations of other models, for | 
 | additional testing and full support, would be much appreciated. | 
 |  | 
 |  | 
 | 6. Module dependencies | 
 | ====================== | 
 | For it to work properly, the driver needs kernel support for Video4Linux, USB | 
 | and I2C, and the "ovcamchip" module for the image sensor. Make sure you are not | 
 | actually using any external "ovcamchip" module, given that the W996[87]CF  | 
 | driver depends on the version of the module present in the official kernels. | 
 |  | 
 | The following options of the kernel configuration file must be enabled and | 
 | corresponding modules must be compiled: | 
 |  | 
 | 	# Multimedia devices | 
 | 	# | 
 | 	CONFIG_VIDEO_DEV=m | 
 |  | 
 | 	# I2C support | 
 | 	# | 
 | 	CONFIG_I2C=m | 
 |  | 
 | The I2C core module can be compiled statically in the kernel as well. | 
 |  | 
 | 	# OmniVision Camera Chip support | 
 | 	# | 
 | 	CONFIG_VIDEO_OVCAMCHIP=m | 
 |  | 
 | 	# USB support | 
 | 	# | 
 | 	CONFIG_USB=m | 
 |  | 
 | In addition, depending on the hardware being used, only one of the modules | 
 | below is necessary: | 
 |  | 
 | 	# USB Host Controller Drivers | 
 | 	# | 
 | 	CONFIG_USB_EHCI_HCD=m | 
 | 	CONFIG_USB_UHCI_HCD=m | 
 | 	CONFIG_USB_OHCI_HCD=m | 
 |  | 
 | And finally: | 
 |  | 
 | 	# USB Multimedia devices | 
 | 	# | 
 | 	CONFIG_USB_W9968CF=m | 
 |  | 
 |  | 
 | 7. Module loading | 
 | ================= | 
 | To use the driver, it is necessary to load the "w9968cf" module into memory | 
 | after every other module required. | 
 |  | 
 | Loading can be done this way, from root: | 
 |  | 
 | 	[root@localhost home]# modprobe usbcore | 
 | 	[root@localhost home]# modprobe i2c-core | 
 | 	[root@localhost home]# modprobe videodev | 
 | 	[root@localhost home]# modprobe w9968cf | 
 |  | 
 | At this point the pertinent devices should be recognized: "dmesg" can be used | 
 | to analyze kernel messages: | 
 |  | 
 | 	[user@localhost home]$ dmesg | 
 |  | 
 | There are a lot of parameters the module can use to change the default | 
 | settings for each device. To list every possible parameter with a brief | 
 | explanation about them and which syntax to use, it is recommended to run the | 
 | "modinfo" command: | 
 |  | 
 | 	[root@locahost home]# modinfo w9968cf | 
 |  | 
 |  | 
 | 8. Module parameters | 
 | ==================== | 
 | Module parameters are listed below: | 
 | ------------------------------------------------------------------------------- | 
 | Name:            ovmod_load | 
 | Type:            bool | 
 | Syntax:          <0|1> | 
 | Description:     Automatic 'ovcamchip' module loading: 0 disabled, 1 enabled. | 
 |                  If enabled, 'insmod' searches for the required 'ovcamchip' | 
 |                  module in the system, according to its configuration, and | 
 |                  loads that module automatically. This action is performed as | 
 |                  once soon as the 'w9968cf' module is loaded into memory. | 
 | Default:         1 | 
 | Note:            The kernel must be compiled with the CONFIG_KMOD option | 
 |                  enabled for the 'ovcamchip' module to be loaded and for | 
 |                  this parameter to be present. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           vppmod_load | 
 | Type:           bool | 
 | Syntax:         <0|1> | 
 | Description:    Automatic 'w9968cf-vpp' module loading: 0 disabled, 1 enabled. | 
 |                 If enabled, every time an application attempts to open a | 
 |                 camera, 'insmod' searches for the video post-processing module | 
 |                 in the system and loads it automatically (if present). | 
 |                 The optional 'w9968cf-vpp' module adds extra image manipulation | 
 |                 capabilities to the 'w9968cf' module,like software up-scaling, | 
 |                 colour conversions and video decompression for very high frame | 
 |                 rates. | 
 | Default:        1 | 
 | Note:           The kernel must be compiled with the CONFIG_KMOD option | 
 |                 enabled for the 'w9968cf-vpp' module to be loaded and for | 
 |                 this parameter to be present. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           simcams  | 
 | Type:           int  | 
 | Syntax:         <n>  | 
 | Description:    Number of cameras allowed to stream simultaneously. | 
 |                 n may vary from 0 to 32. | 
 | Default:        32 | 
 | ------------------------------------------------------------------------------- | 
 | Name:           video_nr | 
 | Type:           int array (min = 0, max = 32) | 
 | Syntax:         <-1|n[,...]>  | 
 | Description:    Specify V4L minor mode number. | 
 |                 -1 = use next available | 
 |                  n = use minor number n | 
 |                 You can specify up to 32 cameras this way. | 
 |                 For example: | 
 |                 video_nr=-1,2,-1 would assign minor number 2 to the second | 
 |                 recognized camera and use auto for the first one and for every | 
 |                 other camera. | 
 | Default:        -1 | 
 | ------------------------------------------------------------------------------- | 
 | Name:           packet_size | 
 | Type:           int array (min = 0, max = 32) | 
 | Syntax:         <n[,...]>  | 
 | Description:    Specify the maximum data payload size in bytes for alternate | 
 |                 settings, for each device. n is scaled between 63 and 1023. | 
 | Default:        1023 | 
 | ------------------------------------------------------------------------------- | 
 | Name:           max_buffers | 
 | Type:           int array (min = 0, max = 32) | 
 | Syntax:         <n[,...]> | 
 | Description:    For advanced users. | 
 |                 Specify the maximum number of video frame buffers to allocate | 
 |                 for each device, from 2 to 32. | 
 | Default:        2 | 
 | ------------------------------------------------------------------------------- | 
 | Name:           double_buffer | 
 | Type:           bool array (min = 0, max = 32) | 
 | Syntax:         <0|1[,...]>  | 
 | Description:    Hardware double buffering: 0 disabled, 1 enabled. | 
 |                 It should be enabled if you want smooth video output: if you | 
 |                 obtain out of sync. video, disable it, or try to | 
 |                 decrease the 'clockdiv' module parameter value. | 
 | Default:        1 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           clamping | 
 | Type:           bool array (min = 0, max = 32) | 
 | Syntax:         <0|1[,...]>  | 
 | Description:    Video data clamping: 0 disabled, 1 enabled. | 
 | Default:        0 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           filter_type | 
 | Type:           int array (min = 0, max = 32) | 
 | Syntax:         <0|1|2[,...]>  | 
 | Description:    Video filter type. | 
 |                 0 none, 1 (1-2-1) 3-tap filter, 2 (2-3-6-3-2) 5-tap filter. | 
 |                 The filter is used to reduce noise and aliasing artifacts | 
 |                 produced by the CCD or CMOS image sensor. | 
 | Default:        0 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           largeview | 
 | Type:           bool array (min = 0, max = 32) | 
 | Syntax:         <0|1[,...]>  | 
 | Description:    Large view: 0 disabled, 1 enabled. | 
 | Default:        1 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           upscaling | 
 | Type:           bool array (min = 0, max = 32) | 
 | Syntax:         <0|1[,...]>  | 
 | Description:    Software scaling (for non-compressed video only): | 
 |                 0 disabled, 1 enabled. | 
 |                 Disable it if you have a slow CPU or you don't have enough | 
 |                 memory. | 
 | Default:        0 for every device. | 
 | Note:           If 'w9968cf-vpp' is not present, this parameter is set to 0. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           decompression | 
 | Type:           int array (min = 0, max = 32) | 
 | Syntax:         <0|1|2[,...]> | 
 | Description:    Software video decompression: | 
 |                 0 = disables decompression | 
 |                     (doesn't allow formats needing decompression). | 
 |                 1 = forces decompression | 
 |                     (allows formats needing decompression only). | 
 |                 2 = allows any permitted formats. | 
 |                 Formats supporting (de)compressed video are YUV422P and | 
 |                 YUV420P/YUV420 in any resolutions where width and height are | 
 |                 multiples of 16. | 
 | Default:        2 for every device. | 
 | Note:           If 'w9968cf-vpp' is not present, forcing decompression is not | 
 |                 allowed; in this case this parameter is set to 2. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           force_palette | 
 | Type:           int array (min = 0, max = 32) | 
 | Syntax:         <0|9|10|13|15|8|7|1|6|3|4|5[,...]> | 
 | Description:    Force picture palette. | 
 |                 In order: | 
 |                  0 = Off - allows any of the following formats: | 
 |                  9 = UYVY    16 bpp - Original video, compression disabled | 
 |                 10 = YUV420  12 bpp - Original video, compression enabled | 
 |                 13 = YUV422P 16 bpp - Original video, compression enabled | 
 |                 15 = YUV420P 12 bpp - Original video, compression enabled | 
 |                  8 = YUVY    16 bpp - Software conversion from UYVY | 
 |                  7 = YUV422  16 bpp - Software conversion from UYVY | 
 |                  1 = GREY     8 bpp - Software conversion from UYVY | 
 |                  6 = RGB555  16 bpp - Software conversion from UYVY | 
 |                  3 = RGB565  16 bpp - Software conversion from UYVY | 
 |                  4 = RGB24   24 bpp - Software conversion from UYVY | 
 |                  5 = RGB32   32 bpp - Software conversion from UYVY | 
 |                 When not 0, this parameter will override 'decompression'. | 
 | Default:        0 for every device. Initial palette is 9 (UYVY). | 
 | Note:           If 'w9968cf-vpp' is not present, this parameter is set to 9. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           force_rgb | 
 | Type:           bool array (min = 0, max = 32) | 
 | Syntax:         <0|1[,...]> | 
 | Description:    Read RGB video data instead of BGR: | 
 |                 1 = use RGB component ordering. | 
 |                 0 = use BGR component ordering. | 
 |                 This parameter has effect when using RGBX palettes only. | 
 | Default:        0 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           autobright | 
 | Type:           bool array (min = 0, max = 32) | 
 | Syntax:         <0|1[,...]> | 
 | Description:    Image sensor automatically changes brightness: | 
 |                 0 = no, 1 = yes | 
 | Default:        0 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           autoexp | 
 | Type:           bool array (min = 0, max = 32) | 
 | Syntax:         <0|1[,...]> | 
 | Description:    Image sensor automatically changes exposure: | 
 |                 0 = no, 1 = yes | 
 | Default:        1 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           lightfreq | 
 | Type:           int array (min = 0, max = 32) | 
 | Syntax:         <50|60[,...]> | 
 | Description:    Light frequency in Hz: | 
 |                 50 for European and Asian lighting, 60 for American lighting. | 
 | Default:        50 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           bandingfilter | 
 | Type:           bool array (min = 0, max = 32) | 
 | Syntax:         <0|1[,...]>  | 
 | Description:    Banding filter to reduce effects of fluorescent  | 
 |                 lighting: | 
 |                 0 disabled, 1 enabled. | 
 |                 This filter tries to reduce the pattern of horizontal | 
 |                 light/dark bands caused by some (usually fluorescent) lighting. | 
 | Default:        0 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           clockdiv | 
 | Type:           int array (min = 0, max = 32) | 
 | Syntax:         <-1|n[,...]> | 
 | Description:    Force pixel clock divisor to a specific value (for experts): | 
 |                 n may vary from 0 to 127. | 
 |                 -1 for automatic value. | 
 |                 See also the 'double_buffer' module parameter. | 
 | Default:        -1 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           backlight | 
 | Type:           bool array (min = 0, max = 32) | 
 | Syntax:         <0|1[,...]> | 
 | Description:    Objects are lit from behind: | 
 |                 0 = no, 1 = yes | 
 | Default:        0 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           mirror | 
 | Type:           bool array (min = 0, max = 32) | 
 | Syntax:         <0|1[,...]> | 
 | Description:    Reverse image horizontally: | 
 |                 0 = no, 1 = yes | 
 | Default:        0 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           monochrome | 
 | Type:           bool array (min = 0, max = 32) | 
 | Syntax:         <0|1[,...]>  | 
 | Description:    The image sensor is monochrome: | 
 |                 0 = no, 1 = yes | 
 | Default:        0 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           brightness | 
 | Type:           long array (min = 0, max = 32) | 
 | Syntax:         <n[,...]> | 
 | Description:    Set picture brightness (0-65535). | 
 |                 This parameter has no effect if 'autobright' is enabled. | 
 | Default:        31000 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           hue | 
 | Type:           long array (min = 0, max = 32) | 
 | Syntax:         <n[,...]> | 
 | Description:    Set picture hue (0-65535). | 
 | Default:        32768 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           colour | 
 | Type:           long array (min = 0, max = 32) | 
 | Syntax:         <n[,...]> | 
 | Description:    Set picture saturation (0-65535). | 
 | Default:        32768 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           contrast | 
 | Type:           long array (min = 0, max = 32) | 
 | Syntax:         <n[,...]>  | 
 | Description:    Set picture contrast (0-65535). | 
 | Default:        50000 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           whiteness | 
 | Type:           long array (min = 0, max = 32) | 
 | Syntax:         <n[,...]>  | 
 | Description:    Set picture whiteness (0-65535). | 
 | Default:        32768 for every device. | 
 | ------------------------------------------------------------------------------- | 
 | Name:           debug | 
 | Type:           int | 
 | Syntax:         <n>  | 
 | Description:    Debugging information level, from 0 to 6: | 
 |                 0 = none (use carefully) | 
 |                 1 = critical errors | 
 |                 2 = significant informations | 
 |                 3 = configuration or general messages | 
 |                 4 = warnings | 
 |                 5 = called functions | 
 |                 6 = function internals | 
 |                 Level 5 and 6 are useful for testing only, when only one | 
 |                 device is used. | 
 | Default:        2 | 
 | ------------------------------------------------------------------------------- | 
 | Name:           specific_debug | 
 | Type:           bool | 
 | Syntax:         <0|1> | 
 | Description:    Enable or disable specific debugging messages: | 
 |                 0 = print messages concerning every level <= 'debug' level. | 
 |                 1 = print messages concerning the level indicated by 'debug'. | 
 | Default:        0 | 
 | ------------------------------------------------------------------------------- | 
 |  | 
 |  | 
 | 9. Contact information | 
 | ====================== | 
 | I may be contacted by e-mail at <[email protected]>. | 
 |  | 
 | I can accept GPG/PGP encrypted e-mail. My GPG key ID is 'FCE635A4'. | 
 | My public 1024-bit key should be available at your keyserver; the fingerprint | 
 | is: '88E8 F32F 7244 68BA 3958  5D40 99DA 5D2A FCE6 35A4'. | 
 |  | 
 |  | 
 | 10. Credits | 
 | ========== | 
 | The development would not have proceed much further without having looked at | 
 | the source code of other drivers and without the help of several persons; in | 
 | particular: | 
 |  | 
 | - the I2C interface to kernel and high-level image sensor control routines have | 
 |   been taken from the OV511 driver by Mark McClelland; | 
 |  | 
 | - memory management code has been copied from the bttv driver by Ralph Metzler, | 
 |   Marcus Metzler and Gerd Knorr; | 
 |  | 
 | - the low-level I2C read function has been written by Frederic Jouault; | 
 |  | 
 | - the low-level I2C fast write function has been written by Piotr Czerczak. |