[linux-dvb] Re: about: Liteon no go? (complete newbie)

Christophe Cattelain xof at skynet.be
Wed Jan 31 13:18:39 CET 2007

I am a newbie too and try to understand why my Pinnacle DVB-S/USB PCTV
450e does not work (not supported yet, ok) and what I can do about it
(it seems that the 400e (2304:020f (?)) is not that different (same
chips/same Ms-Windows driver) and is recently supported (dvb-usb-ttusb2;
ttusb2.c)).  I will post something later about this...

But about 'learning something new', here is where I am :

1/ 'lsusb'  gives the 'USB ID' of the device in the form
<idVendor>:<idProduct> translated using  a file 'usb.ids' (from
http://www.linux-usb.org/usb.ids ; man says it is
/var/lib/usbutils/usb.ids but on Ubuntu Dapper Drake, it is
/var/lib/misc/usb.ids).  This translation is independent of the fact
that a device is supported or not...

2/ When a device is plugged into a system, something has to be done
based on its Id...  I though there was an 'hotplug' process somewhere,
but is now 'udevd' (Ubuntu DD) (man udev ; there are configuration files
in /etc/udev).

I suppose it loads (modprobe) a driver based on information it finds in
something like /lib/modules/2.6.15-27-386/modules.usbmap

In the article http://www.linuxjournal.com/article/5604 , the author
says that the file is generated when one compiles/installs 'modules'.
(I upgraded my DVB modules using part of the procedure described in 

So, when 'dmesg' says a new device has been plugged but doesn't catch
on, it is probably a good idea to look at the file


and try to find the USB-ID returned by 'lsusb' (an <idProduct> with
<idVendor> on the same line).  If there is none to find, try to
upgrade.  If not...  probably write/modify a driver or wait (?)

To try to modify by hand 'modules.usbmap' is probably not enough as, I
suppose, a good driver will probably assess the device it is speeking
with before managing it...

This is what I understand so far  (thanks to
http://www.linuxtv.org/wiki/index.php/AF9015 announced a couple of mails
ago on this list)

Jan Johansson a écrit :
>> Note: the wiki doesn't seem to say that your stick is supported, It
> says 'will soon be supported' or am I wrong?
> Hm, it says "
> All devices below are fully supported by the LinuxTV driver. The
> following drivers are needed for these devices:"
> Any my stick is listed under it.
> I can't seem to get my usbmap to play nice. But I had no idea the file
> was there, so I learned something new :)

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