How to identify USB-video-devices

[Carsten Meier <cm@trexity.de>]

Hello list,

we recently had a discussion on the pvrusb2-list on how to identify a
video-device connected via USB from an userspace app. (Or more precisely
on how to associate config-data with a particular device). This led to
a patch which returned the device's serial-no. in v4l2_capability's
bus_info field. This one has been rejected, but I really feel that this
is the right way to go. Here's the thread:
http://www.isely.net/pipermail/pvrusb2/2009-January/002091.html

I think the meaning of the bus_info-field should be modified slightly
for USB-devices to reflect its dynamic nature. At least a string that
won't change on dis-/reconnect and standby/wake-up-cycles should be
returned. If a device has a unique serial-no. it is a perfect candidate
for this, if not, some USB-port-info should be returned that won't
change if the device is connected to the same port through the same hub.

What do you think?
(BTW: I'm not a kernel-hacker, I'm writing this from the perspective of
an app-developer)

Regards,
Carsten

--
video4linux-list mailing list
Unsubscribe mailto:video4linux-list-request@redhat.com?subject=unsubscribe
https://www.redhat.com/mailman/listinfo/video4linux-list