linux/Documentation/video4linux/zc0301.txt
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   1
   2              ZC0301 and ZC0301P Image Processor and Control Chip
   3                                Driver for Linux
   4              ===================================================
   5
   6                               - Documentation -
   7
   8
   9Index
  10=====
  111.  Copyright
  122.  Disclaimer
  133.  License
  144.  Overview and features
  155.  Module dependencies
  166.  Module loading
  177.  Module parameters
  188.  Supported devices
  199.  Notes for V4L2 application developers
  2010. Contact information
  2111. Credits
  22
  23
  241. Copyright
  25============
  26Copyright (C) 2006-2007 by Luca Risolia <luca.risolia@studio.unibo.it>
  27
  28
  292. Disclaimer
  30=============
  31This software is not developed or sponsored by Z-Star Microelectronics Corp.
  32Trademarks are property of their respective owner.
  33
  34
  353. License
  36==========
  37This program is free software; you can redistribute it and/or modify
  38it under the terms of the GNU General Public License as published by
  39the Free Software Foundation; either version 2 of the License, or
  40(at your option) any later version.
  41
  42This program is distributed in the hope that it will be useful,
  43but WITHOUT ANY WARRANTY; without even the implied warranty of
  44MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  45GNU General Public License for more details.
  46
  47You should have received a copy of the GNU General Public License
  48along with this program; if not, write to the Free Software
  49Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  50
  51
  524. Overview and features
  53========================
  54This driver supports the video interface of the devices mounting the ZC0301 or
  55ZC0301P Image Processors and Control Chips.
  56
  57The driver relies on the Video4Linux2 and USB core modules. It has been
  58designed to run properly on SMP systems as well.
  59
  60The latest version of the ZC0301[P] driver can be found at the following URL:
  61http://www.linux-projects.org/
  62
  63Some of the features of the driver are:
  64
  65- full compliance with the Video4Linux2 API (see also "Notes for V4L2
  66  application developers" paragraph);
  67- available mmap or read/poll methods for video streaming through isochronous
  68  data transfers;
  69- automatic detection of image sensor;
  70- video format is standard JPEG;
  71- dynamic driver control thanks to various module parameters (see "Module
  72  parameters" paragraph);
  73- up to 64 cameras can be handled at the same time; they can be connected and
  74  disconnected from the host many times without turning off the computer, if
  75  the system supports hotplugging;
  76
  77
  785. Module dependencies
  79======================
  80For it to work properly, the driver needs kernel support for Video4Linux and
  81USB.
  82
  83The following options of the kernel configuration file must be enabled and
  84corresponding modules must be compiled:
  85
  86        # Multimedia devices
  87        #
  88        CONFIG_VIDEO_DEV=m
  89
  90        # USB support
  91        #
  92        CONFIG_USB=m
  93
  94In addition, depending on the hardware being used, the modules below are
  95necessary:
  96
  97        # USB Host Controller Drivers
  98        #
  99        CONFIG_USB_EHCI_HCD=m
 100        CONFIG_USB_UHCI_HCD=m
 101        CONFIG_USB_OHCI_HCD=m
 102
 103The ZC0301 controller also provides a built-in microphone interface. It is
 104supported by the USB Audio driver thanks to the ALSA API:
 105
 106        # Sound
 107        #
 108        CONFIG_SOUND=y
 109
 110        # Advanced Linux Sound Architecture
 111        #
 112        CONFIG_SND=m
 113
 114        # USB devices
 115        #
 116        CONFIG_SND_USB_AUDIO=m
 117
 118And finally:
 119
 120        # V4L USB devices
 121        #
 122        CONFIG_USB_ZC0301=m
 123
 124
 1256. Module loading
 126=================
 127To use the driver, it is necessary to load the "zc0301" module into memory
 128after every other module required: "videodev", "v4l2_common", "compat_ioctl32",
 129"usbcore" and, depending on the USB host controller you have, "ehci-hcd",
 130"uhci-hcd" or "ohci-hcd".
 131
 132Loading can be done as shown below:
 133
 134        [root@localhost home]# modprobe zc0301
 135
 136At this point the devices should be recognized. You can invoke "dmesg" to
 137analyze kernel messages and verify that the loading process has gone well:
 138
 139        [user@localhost home]$ dmesg
 140
 141
 1427. Module parameters
 143====================
 144Module parameters are listed below:
 145-------------------------------------------------------------------------------
 146Name:           video_nr
 147Type:           short array (min = 0, max = 64)
 148Syntax:         <-1|n[,...]>
 149Description:    Specify V4L2 minor mode number:
 150                -1 = use next available
 151                 n = use minor number n
 152                You can specify up to 64 cameras this way.
 153                For example:
 154                video_nr=-1,2,-1 would assign minor number 2 to the second
 155                registered camera and use auto for the first one and for every
 156                other camera.
 157Default:        -1
 158-------------------------------------------------------------------------------
 159Name:           force_munmap
 160Type:           bool array (min = 0, max = 64)
 161Syntax:         <0|1[,...]>
 162Description:    Force the application to unmap previously mapped buffer memory
 163                before calling any VIDIOC_S_CROP or VIDIOC_S_FMT ioctl's. Not
 164                all the applications support this feature. This parameter is
 165                specific for each detected camera.
 166                0 = do not force memory unmapping
 167                1 = force memory unmapping (save memory)
 168Default:        0
 169-------------------------------------------------------------------------------
 170Name:           frame_timeout
 171Type:           uint array (min = 0, max = 64)
 172Syntax:         <n[,...]>
 173Description:    Timeout for a video frame in seconds. This parameter is
 174                specific for each detected camera. This parameter can be
 175                changed at runtime thanks to the /sys filesystem interface.
 176Default:        2
 177-------------------------------------------------------------------------------
 178Name:           debug
 179Type:           ushort
 180Syntax:         <n>
 181Description:    Debugging information level, from 0 to 3:
 182                0 = none (use carefully)
 183                1 = critical errors
 184                2 = significant information
 185                3 = more verbose messages
 186                Level 3 is useful for testing only, when only one device
 187                is used at the same time. It also shows some information
 188                about the hardware being detected. This module parameter can be
 189                changed at runtime thanks to the /sys filesystem interface.
 190Default:        2
 191-------------------------------------------------------------------------------
 192
 193
 1948. Supported devices
 195====================
 196None of the names of the companies as well as their products will be mentioned
 197here. They have never collaborated with the author, so no advertising.
 198
 199From the point of view of a driver, what unambiguously identify a device are
 200its vendor and product USB identifiers. Below is a list of known identifiers of
 201devices mounting the ZC0301 Image Processor and Control Chips:
 202
 203Vendor ID  Product ID
 204---------  ----------
 2050x041e     0x4017
 2060x041e     0x401c
 2070x041e     0x401e
 2080x041e     0x401f
 2090x041e     0x4022
 2100x041e     0x4034
 2110x041e     0x4035
 2120x041e     0x4036
 2130x041e     0x403a
 2140x0458     0x7007
 2150x0458     0x700c
 2160x0458     0x700f
 2170x046d     0x08ae
 2180x055f     0xd003
 2190x055f     0xd004
 2200x0ac8     0x0301
 2210x0ac8     0x301b
 2220x0ac8     0x303b
 2230x10fd     0x0128
 2240x10fd     0x8050
 2250x10fd     0x804e
 226
 227The list above does not imply that all those devices work with this driver: up
 228until now only the ones that mount the following image sensors are supported;
 229kernel messages will always tell you whether this is the case:
 230
 231Model       Manufacturer
 232-----       ------------
 233PAS202BCB   PixArt Imaging, Inc.
 234PB-0330     Photobit Corporation
 235
 236
 2379. Notes for V4L2 application developers
 238========================================
 239This driver follows the V4L2 API specifications. In particular, it enforces two
 240rules:
 241
 242- exactly one I/O method, either "mmap" or "read", is associated with each
 243file descriptor. Once it is selected, the application must close and reopen the
 244device to switch to the other I/O method;
 245
 246- although it is not mandatory, previously mapped buffer memory should always
 247be unmapped before calling any "VIDIOC_S_CROP" or "VIDIOC_S_FMT" ioctl's.
 248The same number of buffers as before will be allocated again to match the size
 249of the new video frames, so you have to map the buffers again before any I/O
 250attempts on them.
 251
 252
 25310. Contact information
 254=======================
 255The author may be contacted by e-mail at <luca.risolia@studio.unibo.it>.
 256
 257GPG/PGP encrypted e-mail's are accepted. The GPG key ID of the author is
 258'FCE635A4'; the public 1024-bit key should be available at any keyserver;
 259the fingerprint is: '88E8 F32F 7244 68BA 3958  5D40 99DA 5D2A FCE6 35A4'.
 260
 261
 26211. Credits
 263===========
 264- Information about the chip internals needed to enable the I2C protocol have
 265  been taken from the documentation of the ZC030x Video4Linux1 driver written
 266  by Andrew Birkett <andy@nobugs.org>;
 267- The initialization values of the ZC0301 controller connected to the PAS202BCB
 268  and PB-0330 image sensors have been taken from the SPCA5XX driver maintained
 269  by Michel Xhaard <mxhaard@magic.fr>;
 270- Stanislav Lechev donated one camera.
 271
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