1 This is a driver for the CPiA PPC2 driven parallel connected
2 Camera. For example the Creative WebcamII is CPiA driven.
3
4 ) [1]Peter Pregler, Linz 2000, published under the [2]GNU GPL
5
6 ---------------------------------------------------------------------------
7
8 USAGE:
9
10 General:
11 ========
12
13 1) Make sure you have created the video devices (/dev/video*):
14
15 - if you have a recent MAKEDEV do a 'cd /dev;./MAKEDEV video'
16 - otherwise do a:
17
18 cd /dev
19 mknod video0 c 81 0
20 ln -s video0 video
21
22 2) Compile the kernel (see below for the list of options to use),
23 configure your parport and reboot.
24
25 3) If all worked well you should get messages similar
26 to the following (your versions may be different) on the console:
27
28 V4L-Driver for Vision CPiA based cameras v0.7.4
29 parport0: read2 timeout.
30 parport0: Multimedia device, VLSI Vision Ltd PPC2
31 Parallel port driver for Vision CPiA based camera
32 CPIA Version: 1.20 (2.0)
33 CPIA PnP-ID: 0553:0002:0100
34 VP-Version: 1.0 0100
35 1 camera(s) found
36
37
38 As modules:
39 ===========
40
41 Make sure you have selected the following kernel options (you can
42 select all stuff as modules):
43
44 The cpia-stuff is in the section 'Character devices -> Video For Linux'.
45
46 CONFIG_PARPORT=m
47 CONFIG_PARPORT_PC=m
48 CONFIG_PARPORT_PC_FIFO=y
49 CONFIG_PARPORT_1284=y
50 CONFIG_VIDEO_DEV=m
51 CONFIG_VIDEO_CPIA=m
52 CONFIG_VIDEO_CPIA_PP=m
53
54 For autoloading of all those modules you need to tell modutils some
55 stuff. Add the following line to your modutils config-file
56 (e.g. /etc/modules.conf or wherever your distribution does store that
57 stuff):
58
59 options parport_pc io=0x378 irq=7 dma=3
60 alias char-major-81 cpia_pp
61
62 The first line tells the dma/irq channels to use. Those _must_ match
63 the settings of your BIOS. Do NOT simply use the values above. See
64 Documentation/parport.txt for more information about this. The second
65 line associates the video-device file with the driver. Of cause you
66 can also load the modules once upon boot (usually done in /etc/modules).
67
68 Linked into the kernel:
69 =======================
70
71 Make sure you have selected the following kernel options. Note that
72 you cannot compile the parport-stuff as modules and the cpia-driver
73 statically (the other way round is okay though).
74
75 The cpia-stuff is in the section 'Character devices -> Video For Linux'.
76
77 CONFIG_PARPORT=y
78 CONFIG_PARPORT_PC=y
79 CONFIG_PARPORT_PC_FIFO=y
80 CONFIG_PARPORT_1284=y
81 CONFIG_VIDEO_DEV=y
82 CONFIG_VIDEO_CPIA=y
83 CONFIG_VIDEO_CPIA_PP=y
84
85 To use DMA/irq you will need to tell the kernel upon boot time the
86 hardware configuration of the parport. You can give the boot-parameter
87 at the LILO-prompt or specify it in lilo.conf. I use the following
88 append-line in lilo.conf:
89
90 append="parport=0x378,7,3"
91
92 See Documentation/parport.txt for more information about the
93 configuration of the parport and the values given above. Do not simply
94 use the values given above.
95
96 ---------------------------------------------------------------------------
97 FEATURES:
98
99 - mmap/read v4l-interface (but no overlay)
100 - image formats: CIF/QCIF, SIF/QSIF, various others used by isabel;
101 note: all sizes except CIF/QCIF are implemented by clipping, i.e.
102 pixels are not uploaded from the camera
103 - palettes: VIDEO_PALETTE_GRAY, VIDEO_PALETTE_RGB565, VIDEO_PALETTE_RGB555,
104 VIDEO_PALETTE_RGB24, VIDEO_PALETTE_RGB32, VIDEO_PALETTE_YUYV,
105 VIDEO_PALETTE_UYVY, VIDEO_PALETTE_YUV422
106 - state information (color balance, exposure, ...) is preserved between
107 device opens
108 - complete control over camera via proc-interface (_all_ camera settings are
109 supported), there is also a python-gtk application available for this [3]
110 - works under SMP (but the driver is completely serialized and synchronous)
111 so you get no benefit from SMP, but at least it does not crash your box
112 - might work for non-Intel architecture, let us know about this
113
114 ---------------------------------------------------------------------------
115 TESTED APPLICATIONS:
116
117 - a simple test application based on Xt is available at [3]
118 - another test-application based on gqcam-0.4 (uses GTK)
119 - gqcam-0.6 should work
120 - xawtv-3.x (also the webcam software)
121 - xawtv-2.46
122 - w3cam (cgi-interface and vidcat, e.g. you may try out 'vidcat |xv
123 -maxpect -root -quit +noresetroot -rmode 5 -')
124 - vic, the MBONE video conferencing tool (version 2.8ucl4-1)
125 - isabel 3R4beta (barely working, but AFAICT all the problems are on
126 their side)
127 - camserv-0.40
128
129 See [3] for pointers to v4l-applications.
130
131 ---------------------------------------------------------------------------
132 KNOWN PROBLEMS:
133
134 - some applications do not handle the image format correctly, you will
135 see strange horizontal stripes instead of a nice picture -> make sure
136 your application does use a supported image size or queries the driver
137 for the actually used size (reason behind this: the camera cannot
138 provide any image format, so if size NxM is requested the driver will
139 use a format to the closest fitting N1xM1, the application should now
140 query for this granted size, most applications do not).
141 - all the todo ;)
142 - if there is not enough light and the picture is too dark try to
143 adjust the SetSensorFPS setting, automatic frame rate adjustment
144 has its price
145 - do not try out isabel 3R4beta (built 135), you will be disappointed
146
147 ---------------------------------------------------------------------------
148 TODO:
149
150 - multiple camera support (struct camera or something) - This should work,
151 but hasn't been tested yet.
152 - architecture independence?
153 - SMP-safe asynchronous mmap interface
154 - nibble mode for old parport interfaces
155 - streaming capture, this should give a performance gain
156
157 ---------------------------------------------------------------------------
158 IMPLEMENTATION NOTES:
159
160 The camera can act in two modes, streaming or grabbing. Right now a
161 polling grab-scheme is used. Maybe interrupt driven streaming will be
162 used for a asynchronous mmap interface in the next major release of the
163 driver. This might give a better frame rate.
164
165 ---------------------------------------------------------------------------
166 THANKS (in no particular order):
167
168 - Scott J. Bertin <sbertin@mindspring.com> for cleanups, the proc-filesystem
169 and much more
170 - Henry Bruce <whb@vvl.co.uk> for providing developers information about
171 the CPiA chip, I wish all companies would treat Linux as seriously
172 - Karoly Erdei <Karoly.Erdei@risc.uni-linz.ac.at> and RISC-Linz for being
173 my boss ;) resp. my employer and for providing me the hardware and
174 allow me to devote some working time to this project
175 - Manuel J. Petit de Gabriel <mpetit@dit.upm.es> for providing help
176 with Isabel (http://isabel.dit.upm.es/)
177 - Bas Huisman <bhuism@cs.utwente.nl> for writing the initial parport code
178 - Jarl Totland <Jarl.Totland@bdc.no> for setting up the mailing list
179 and maintaining the web-server[3]
180 - Chris Whiteford <Chris@informinteractive.com> for fixes related to the
181 1.02 firmware
182 - special kudos to all the tester whose machines crashed and/or
183 will crash. :)
184
185 ---------------------------------------------------------------------------
186 REFERENCES
187
188 1. http://www.risc.uni-linz.ac.at/people/ppregler
189 mailto:Peter_Pregler@email.com
190 2. see the file COPYING in the top directory of the kernel tree
191 3. http://webcam.sourceforge.net/
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