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cpia usb摄像头的驱动程序源码。需要video4linux和i2c-core支持

Notes for use with 2.4 kernels.


****************************************************
IMPORTANT:   
   For users of RedHat 7.x/8.x 2.4.18 kernels
   (and other 2.4.18 kernels patched to provide the new
   Video4Linux interface - e.g., 2.4.18-ac* kernels)

Changes (in the Linux-2.4.19 kernel) are patched into these 2.4.18
kernels.   If you have such a kernel, and you disconnect your CPiA
camera while it is working, a deadlock that can eventually crash your
system will occur.   To fix this, apply the patch

    redhat-2.4.18-kernel-videodev.patch

to drivers/media/video/videodev.c

(No action is necessary for standard 2.4.18 kernels, or any other
kernel release, though if you also use non-cpia Video4Linux drivers in
2.4.19 or 2.4.20 kernels, it's a good idea to apply this patch...)
**************************************************** 	



The cpia driver included in the 2.4.x series Linux kernels (x <=20) is an 
older version that does not yet include all the features and improvements
found in this driver available at http://webcam.sourceforge.net.

Some earlier 2.4.x. kernels have a cpia driver with disabled camera
control so cpia-control cannot be used, or do not support features
of the Intel Play QX3 microscope, and do not support DMA access by fast
ECP parallel ports.
[The support for DMA access for parallel port cpia cameras 
is now available here, thanks to Blaise Gassend.]

To use with 2.4.x kernels:

(a) compile the kernel with cpia support.  Activate this in the
multimedia devices/video for linux section, select 
 	CPiA Video for Linux (CONFIG_VIDEO_CPIA)
and, as appropriate,
	CPiA Parallel Port lowlevel support (CONFIG_VIDEO_CPIA_PP)
	CPiA USB lowlevel support  (CONFIG_VIDEO_CPIA_USB)

(b) replace the files  cpia.c cpia_usb.c cpia_pp.c cpia.h in the
kernel source subdirectory drivers/media/video/
with the ones from here (in the subdirectory "module"), and recompile.

If the kernel source is in /usr/src/linux-2.4/....
go to .../drivers/media/video/
rename the kernel cpia files to cpia.c.orig, cpia.h.orig, etc. and copy 
the new versions into this directory.  Then cd to /usr/src/linux-2.4, and

make modules

You can now do 

make modules_install 

or (to avoid messing with your system too much) 
cp drivers/media/video/cpia*o /lib/modules/`uname -r`/kernel/drivers/media/video
depmod -ae

This should replace the old drivers with the new ones.

 ---
Using the CPiA camera:  (see also the appended file below ("cpia.txt"))

If you compiled the drivers as modules, load them:

modprobe cpia_usb 

or 

modprobe cpia_pp 

as appropriate for your camera. 

start a v4l viewer, like gqcam (see below)

If the camera is at /dev/video0, 
cat /proc/cpia/video0 to see  what you can control:
e.g.,
echo color_balance_mode: manual > /proc/cpia/video0
echo toplight: on > /proc/cpia/video0     
(this is for the QX3 microscope only)


The program cpia-control by Peter Prengler, available at the 
sourceforge site, is a graphical interface to (most) of these features,
using /proc/cpia/video[n].   It is now at a cpia-control-0.4 release.


I found gqcam-0.9 works well with the cpia drivers
(get it at http://cse.unl.edu/~cluening/gqcam/ ), 
but it needs the following patch
===========begin patch===============================
diff -uNr gqcam-0.9/gqcam.c gqcam-0.9-patched/gqcam.c
--- gqcam-0.9/gqcam.c   Tue Nov  7 11:52:06 2000
+++ gqcam-0.9-patched/gqcam.c   Tue Dec 17 04:03:34 2002
@@ -55,7 +55,7 @@
   camera->savetype = PNG;
   camera->capture = 1;
   camera->dev = 0;
-  strcpy(camera->devname, "/dev/video");
+  strcpy(camera->devname, "/dev/video0");
   camera->docked = 1;
   camera->dump=0;
   camera->speed_fastest = 0;
@@ -96,13 +96,16 @@
   ioctl(camera->dev, VIDIOCGWIN, &camera->vid_win);
   ioctl(camera->dev, VIDIOCGPICT, &camera->vid_pic);

-  for (i = 0; i < 32; i++) {
-    vid_clips[i].x      = 0;
-    vid_clips[i].y      = 0;
-    vid_clips[i].width  = 0;
-    vid_clips[i].height = 0;
-  }
+  camera->vid_win.clips = NULL;
+  if (camera->vid_caps.type & VID_TYPE_CLIPPING) {
+    for (i = 0; i < 32; i++) {
+      vid_clips[i].x      = 0;
+      vid_clips[i].y      = 0;
+      vid_clips[i].width  = 0;
+      vid_clips[i].height = 0;
+    }
   camera->vid_win.clips = vid_clips;
+  }
   camera->vid_win.clipcount = 0;

   if (camera->vid_caps.type & VID_TYPE_MONOCHROME) {
@@ -188,13 +191,16 @@

 void open_cam(struct Camera *camera)
 {
+  char devname[80];
   if((camera->dev<=0)){
     camera->dev = open(camera->devname, O_RDWR);
-    //    printf("Opening: %d\n", camera->dev);
+    printf("Opening: %s %d\n", camera->devname,camera->dev);
+    snprintf(devname,80,"%s",camera->devname);
     if (camera->dev < 0) {
-      perror("/dev/video");
+      perror(devname);
       exit(1);
     }
+    print_cam_info(camera);
   }
   pthread_mutex_unlock( &camera->iscam_mutex );
 }
=============end gqcam patch==============================
[e-mail]
2002-05-11


--------------------cpia.txt--------------------------------------------


This is a video4linux (v4l1) driver for cameras that use the (now obsolete)
CPiA PPC2 chipset.  Both parallel port and USB-connected cameras are supported.

The website for this driver is:
http://webcam.sourceforge.net
http://sourceforge.net/projects/webcam

Author:  [1]Peter Pregler, Linz 2000, published under the [2]GNU GPL

This driver is no longer in active development but is is "low-maintenance"
mode[5]:   contact the cpia mailing list for maintenance issues. 
(see http://webcam.sourceforge.net for mailing list details) 
Recent work on improving USB and parallel port transfer modes has been
done, though. (December 2002).
---------------------------------------------------
Devices know to be supported by this driver are:

(a) Parallel port webcams: 

Creative Video Blaster WebCam II
CVideo-Mail Express
CU-SeeMe Cam Kit
Digicom Galileo Plus
ZoomCam


The driver supports High-speed ECP parallel ports, and will use DMA
if available.   It now will also support standard IEEE1284 parallel ports,
using software emulation of ECP on "BiDirectional" (TRISTATE) ports, 
or a special enhanced "Nibble" mode on non-Bidirectional PCSPP ports; 
but these mode have a low transfer rate of about 60KB/s (about one
compressed frame every one or two seconds).  The CPiA firmware does not
support EPP parallel port modes.

The source code for the Windows(TM) 9x parallel port driver has been released 
by the CPiA chip maker STM under the GPL as:  
      http://webcam.sourceforge.net/docs/ppc2.zip
and the CPiA Developer's Guide is also available there.

(b) USB devices:

Intel Play QX3 and QX3+ Microscopes

USB webcams:

Aiptek HyperVcam Fun USB (some use the OV511 chip instead of CPiA!)
Creative Video Blaster WebCam II
Digicom Galileo USB
Dynalink Digital Camera
Ezonics EZCam (Not Pro or Plus)
Microtek EyeStar
Pace Colour Video Camera
SuperCam WonderEye
TCE Netcam 310 USB
Terracam USB(Not Pro) 
Trust SpaceC@m Lite
Utobia USB Camera
ZoomCam

---------------------------------------------------------------------------

USAGE:

General:
========

1) Make sure you have created the video devices (/dev/video*):

- if you have a recent MAKEDEV do a 'cd /dev;./MAKEDEV video'
- otherwise do a:

cd /dev
mknod video0 c 81 0

Repeat for /dev/video1, /dev/video2 etc as needed.

2) Compile the kernel (see below for the list of options to use).
   If applicable, configure your parport.  Reboot.

3) If all worked well you should get messages similar
   to the following (your versions may be different) on the console:

V4L-Driver for Vision CPiA based cameras v1.2.2
parport0: read2 timeout.
parport0: Multimedia device, VLSI Vision Ltd PPC2
Parallel port driver for Vision CPiA based camera
  CPIA Version: 1.20 (2.0)
  CPIA PnP-ID: 0553:0002:0100
  VP-Version: 1.0 0100
  1 camera(s) found


Building the Driver as modules:
============================

Make sure you have selected the following kernel options (you can
select all stuff as modules):


parallel port:

CONFIG_PARPORT=m
CONFIG_PARPORT_PC=m
CONFIG_PARPORT_1284=y
CONFIG_PARPORT_PC_FIFO=y    (needed for high-speed ECP modes, if available)

usb:
CONFIG_USB=m
CONFIG_USB_[OHCI/UHCI/UHCI_ALT/EHCI_HCD]=m  (as appropiate for your usb)


The cpia-stuff is in the section 'Character devices -> Video For Linux'.
CONFIG_VIDEO_DEV=m
CONFIG_VIDEO_CPIA=m

also, depending on whether you have parport or USB cameras (or both):

CONFIG_VIDEO_CPIA_PP=m
CONFIG_VIDEO_CPIA_USB=m

Finally for controlling the camera using the /proc/cpia/video<n> 
interface you need
CONFIG_PROC_FS=y

The cpia module supports the module parameter option:

options cpia usb_alt=[1,2,3]  (initial "usb alt interface" setting <usb_alt>)

The usb_alt parameter only affects usb cameras, and selects the  
"alternate usb interface setting " that is assigned when the camera is 
first registered (i.e., when it is initially plugged in to the USB
hub, and registered as /dev/video<n>). 
(see below)

The cpia_pp module supports module options for selecting parallel ports:
options cpia_pp parport=[none,auto,0,1,2,...]   (just like lp)

If your parallel port has ECP hardware, it will not get used unless you:
(a) Build the kernel with CONFIG_PARPORT_PC_FIFO=y  
(b) You may have to select ECP mode for the parallel port in the computer's 
    BIOS setup.
(c) load the parport_pc module with options specifying the interrupt
    (and dma channel, if available) 

For (c), add the following lines to your modutils config-file
(e.g. /etc/modules.conf or wherever your distribution does store that
stuff):

options parport_pc io=0x378 irq=7 dma=3
alias char-major-81 cpia_pp

The first line tells the dma/irq channels to use. Those _must_ match
the settings of your BIOS. Do NOT simply use the values above.  See
Documentation/parport.txt for more information about this. The second
line associates the video-device file with the driver. Of cause you
can also load the modules once upon boot (usually done in /etc/modules).


Building the Driver linked into the kernel:
============================================

Make sure you have selected the following kernel options. Note that
you cannot compile the parport-stuff/usb-stuff as modules and the cpia-driver
statically (the other way round is okay though).