Hi Andy, > This is working fine except that hotplug is calling the script > (/etc/hotplug/speedtouch) 3 times, once for each of these $DEVPATH values: > > DEVPATH=/devices/pci0000:00/0000:00:1d.2/usb4/4-1/4-1:1.0 > DEVPATH=/devices/pci0000:00/0000:00:1d.2/usb4/4-1/4-1:1.1 > DEVPATH=/devices/pci0000:00/0000:00:1d.2/usb4/4-1/4-1:1.2 > > Now firstly what are each of these values; I mean do they represent some sort > of interface provided by the speedtouch modem via usb? How do you articulate > what they are?
the modem has three interfaces (one for monitoring the modem, one for data transfer, and one for uploading firmware). Hotplug is called for each of them. The DEVPATH gives you a directory containing a number of files, for example bInterfaceNumber. This is 0, 1 or 2 depending on which interface it is. I think the best strategy is to check whether it is "1", and bail out if not. The reason I choose "1" is that in theory the kernel module could work fine if interfaces 0 or 2 were being controlled by a user-space program (in which case you might not get hotplug events for them); but interface 1 is essential. This is an entirely theoretical consideration which is irrelevant in your case, but hey! > Now I need to modify my init script (which waits for "Line up" to appear in > /proc/net/atm/speedtch:0, calls pppd and arranges the removal script) so that > it only reacts to one of these events (was thinking the "*:1.0" one for > maximum portability). Does this seem reasonable? > > Finally I noticed yesterday the MTU of the interface (ppp0) was 32725!!! I > have now set this to 1492, after looking about on the net, but do I need to > set the MRU value, and is 1492 correct or should it be 1500? I know that > this depends on ISP, and mine is Pipex in the UK. I think the thing about the MTU is that it shouldn't be bigger than some value (determined by the ISP), however it is OK to be smaller. Probably the value 1492 represents 1500-ppp_overhead. Anyway, you can always try it and see (you'll need to upload/download some big files to actually use packets of MTU size). With my previous ISP I was able to send and receive 64k packets perfectly fine... If you want to play that kind of game, you might also want to adjust the module parameters (you can see these using modinfo usbatm or modinfo speedtch depending on your kernel version). They allow you to do much larger data transfers to the modem if you want to (this is not the same as packet size - each transfer can contain several packets, or part of a packet). You can also tell it how many data transfers should be in flight at any one time. This kind of thing is only really useful if you use a large MTU. Most people won't care about this kind of thing, and as far as I know no-one actually uses any of it! But since I programmed it, I'm still hoping it might prove useful to someone... > Thanks for all your great efforts with speedtouch and keep up the work! Thanks! D. Liste de diffusion modem ALCATEL SpeedTouch USB Pour se d�sinscrire : mailto:[EMAIL PROTECTED]
