On Fri, Mar 04, 2005 at 10:51:21AM +0100, Duncan Sands wrote: > > 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!
OK thanks Duncan, I will add a case statement and bail for anything other than DEVPATH=*1.1 > > > 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... I'm using 2.6.11 and it's this: trojanfoe:~# modinfo speedtch filename: /lib/modules/2.6.11/kernel/drivers/usb/atm/speedtch.ko author: Johan Verrept, Duncan Sands <[EMAIL PROTECTED]> description: Alcatel SpeedTouch USB driver version 1.8 license: GPL version: 1.8 vermagic: 2.6.11 PENTIUMIII gcc-3.3 depends: usb_atm alias: usb:v06B9p4061dl*dh*dc*dsc*dp*ic*isc*ip* srcversion: 22749B4497820BD7CEB96A0 parm: sw_buffering:Enable software buffering (uint) parm: dl_512_first:Read 512 bytes before sending firmware (bool) I will play with the params and MTU and see what works best. But what about MRU? Thanks for your swift and informative response! Cheers, Andy Liste de diffusion modem ALCATEL SpeedTouch USB Pour se d�sinscrire : mailto:[EMAIL PROTECTED]
