MC7304 connection?

[Bjørn Mork]

Dan Williams <dcbw at redhat.com> writes:

> Since the interfaces are effectively paired, is ModemManager detecting
> the #1 WDM and the #3 net ports?  Is there a way to ensure that if MM
> picks WDM #1 that it also uses net #1 as the data port?  If we don't
> have any kind of links in sysfs, I guess we could poke udev for USB
> interface numbers or something, but that's icky.

The links will be there, but I don't know if it's less icky than using
the interface numbers directly.  It's basically the same - both the net
and the usbmisc dev will be children of the USB interface device:

bjorn at nemi:~$ ls -ld /sys/bus/usb/devices/2-4\:1.*/{net,usbmisc}/*
drwxr-xr-x 5 root root 0 May 21 15:23 /sys/bus/usb/devices/2-4:1.19/net/wwan1
drwxr-xr-x 3 root root 0 May 21 15:23 /sys/bus/usb/devices/2-4:1.19/usbmisc/cdc-wdm1
drwxr-xr-x 5 root root 0 May 21 15:23 /sys/bus/usb/devices/2-4:1.20/net/wwan2
drwxr-xr-x 3 root root 0 May 21 15:23 /sys/bus/usb/devices/2-4:1.20/usbmisc/cdc-wdm2
drwxr-xr-x 5 root root 0 May 21 15:23 /sys/bus/usb/devices/2-4:1.8/net/wwan0
drwxr-xr-x 3 root root 0 May 21 15:23 /sys/bus/usb/devices/2-4:1.8/usbmisc/cdc-wdm0


Find the cdc-wdm device via the netdev:

bjorn at nemi:~$ ls -l /sys/class/net/wwan1/device/usbmisc
total 0
drwxr-xr-x 3 root root 0 May 21 15:23 cdc-wdm1


Or the other way round:

bjorn at nemi:~$ ls -l /sys/class/usbmisc/cdc-wdm1/device/net
total 0
drwxr-xr-x 5 root root 0 May 21 15:23 wwan1



Bjørn