[Nut-upsdev] More information on USB bus

[Arjen de Korte]

> On 8/31/07, Arjen de Korte <nut+devel at de-korte.org> wrote:
>> When I plug in a device, the kernel will not only tell me to which USB
>> bus it is connected, but also the socket it is plugged into:
>>
>> > Aug 31 22:06:07 miffy kernel: usb 1-1: new low speed USB device using
>> uhci_hcd and address 31
>> > Aug 31 22:06:08 miffy kernel: usb 1-1: new device found,
>> idVendor=0463, idProduct=ffff
>> > Aug 31 22:06:08 miffy kernel: usb 1-1: new device strings: Mfr=1,
>> Product=2, SerialNumber=3
>> > Aug 31 22:06:08 miffy kernel: usb 1-1: Product: Evolution
>> > Aug 31 22:06:08 miffy kernel: usb 1-1: Manufacturer: MGE UPS SYSTEMS
>> > Aug 31 22:06:08 miffy kernel: usb 1-1: SerialNumber: AV1H2402G
>> > Aug 31 22:06:08 miffy kernel: usb 1-1: configuration #1 chosen from 1
>> choice
>>
>> On USB bus 1, I have two sockets and it clearly makes a difference in
>> which I put the connector. The kernel will report either 'usb 1-1' or
>> 'usb 1-2'. Is there a way to get to this information through libusb?
>> From a posting today on nut-users, it looks like we need more
>> granularity than just the bus.
> I think that is something you can infer from the usb_device structure
> (the filename member). Not sure if that's considered portable, though.

I'll have a look. It seemed obvious that this would be in the usb_bus
structure, but that proved to be a wrong assumption.

> I am a little concerned about how that would work in practice -
> different kernels might use different names there.

That's probably something autoconf could deal with for us, so I'm not that
worried about that.

Best regards, Arjen