Re: understanding firmware loader for speedtouch (kernel 2.6.21.5)

From: Duncan Sands
Date: Wed Jul 11 2007 - 09:07:30 EST


Hi,

> Actually I had to mount it (I hope that not having it mounted does
> not change a lot in this matter).

probably not. Not having sysfs mounted can cause hotplug to fail,
but I think not having /proc/bus/usb mounted shouldn't cause any
trouble nowadays.

> I:* If#= 1 Alt= 3 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=speedtch
> E: Ad=06(O) Atr=02(Bulk) MxPS= 64 Ivl=0ms
> E: Ad=07(O) Atr=02(Bulk) MxPS= 64 Ivl=0ms
> E: Ad=87(I) Atr=01(Isoc) MxPS= 960 Ivl=1ms

The * means that this altsetting is being used - this is the altsetting
when using isochronous mode. So it looks to me like isochronous mode is
being used.

> I have CONFIG_USB_DEBUG=y set in kernel. However I do not see any of
> the messages you are referring to. It does not say that it tried isoc
> and falls to bulk, nothing like that. Also nothing about "setting
> interface to ?? failed".

Most likely it is using isochronous transfer. The question then is: why
is it slow? I will look in my cupboard to see if I have the same modem,
and if so see what speed I can get out of it.

> Which debug option should I switch to see these?

Something like this IIRC:
echo 7 > /proc/sys/kernel/printk
Then it should turn up in dmesg.

Ciao,

Duncan.


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