Re: AW: Problems with Sierra MC 8790 with older firmware revision

[Bjørn Mork <bjorn mork no>]

Aleksander Morgado <aleksander lanedo com> writes:

> Some additional information about this device, forgetting about the APP1
> port issue...
>
> The MC8790 is really a Direct-IP capable device, but without DHCP.

Interesting.  Let's try to figure out how to support that.  Maybe
export the raw fwattr and let userspace figure it out instead?

> The
> sierra_net kernel driver filters the wwan port in the following check:
>
> /* test whether firmware supports DHCP */
> if (!(status == sizeof(fwattr) &&
>      (fwattr & SWI_GET_FW_ATTR_MASK))) {
>     /* found incompatible firmware version */
>     dev_err(&dev->udev->dev, "Incompatible driver and firmware"
>             " versions\n");
>     kfree(priv);
>     return -ENODEV;
> }
>
> If that check is removed, we get a wwan0 which can get connected with
> AT!SCACT, but DHCP won't work on it. I could get the static IP to set
> with AT!SCPADDR, though, but I couldn't get proper gateway or DNS
> addresses. After using the x.x.x.1 address as default route, I could
> actually ping the Internet...

The sierra_net driver sets IFF_NOARP so you shouldn't really need any
gateway address at all.  Just set the default route out on the correct
dev:

  ip route add default dev wwan0



Bjørn