Re: Kamera, Pencam, hotplug, perms

[Achim Bohnet <ach@mpe.mpg.de>]

On Sat, May 10, 2003 at 01:39:49AM -0700, Michael Rudmin wrote:
> Hi, I have a problem which seems like it should have
> come up before, but maybe it's new, because it's got a
> little twist.
> 
> I installed hotplug usb, and have a Argus DC1500
> [essentially a pencam:  it requires USB data transfer,
> and is not just a USB block device].  When I plug in
> my camera, I see in /proc/bus/usb/001 two files, one
> of which is the driver "001" and one of which is the
> camera, with a different number like "005".

Wild guess:
Check if hotplug loads camera q specific kernel module:

	/sbin/lsmod |head
	# plugin camera
	/sbin/lsmod |head

I could not use the usb with DC2400 until I disabled
autoloading of dc2xx for a Kodak DC240.

> 
> Now, I also installed /etc/hotplug/usb/usbcam and all
> that, so that it should adjust the permissions.
> 
> I used the usbcam.group as my source for usbcam, and
> adjusted it to be executable.  Then from the command
> line, I addgroup'd camera, and added my user name to
> the group camera with #adduser myuser camera.
> 
> Note that usbcam.group refers to the group "camera". 
> And now my executable usbcam does, as well.
> 
> I also checked that the Argus' control variables, as
> referenced in /proc/bus/usb/devices, is covered by the
> graphics engine that runs all the permissions stuff.
> 
> Finally, on KDE I set up (control
> panels)::(peripherals)::(camera) to include my Argus
> DC1500.
> 
> When I type in camera:/ in the file manager URL, I get
> my DC1500.  But when I click on it, I get one of two
> messages:  "Cannot claim USB Bus", or sometimes "I/O
> problem.  Cannot read file"  or sometimes "Could not
> read file:  bad parameters".
> 
> Just to see if it was a permissions problem, I rather
> foolishly logged into KDE as root [I know, not a good
> idea, can wreck things], and tried to access the
> camera from there.  No good -- it says "Cannot claim
> USB Bus".  Maybe with time, it would give me the other
> errors instead.  

Try the gphoto2 command line tool. This will test you
if it's a libgphoto/kernel problem or if it KDEs camera
io slave.

If gphoto2 works and camera:/ not you may try digikam.

Achim
> 
> Does anyone know what is going on, and what I have to
> do differently?  I've tried to follow the installation
> instructions everywhere, but I seem to be doing
> something wrong.