How to replace control code in gdm72xx?

[Michalis Pappas <mpappas@fastmail.fm>]

Hi,

I'm currently working on bringing the gdm72xx WiMAX driver out of
staging. The driver currently uses two control channels:

1. The SIOCDEVPRIVATE ioctl to send and receive state messages

2. A customly defined netlink protocol for passing messages verbatim to
the device controller

AFAIK both of the above are deprecated, so I considered switching to
the interface defined in wimax.h, which defines a communication protocol
over generic netlink that replaces (2) nicely. However it is not
compatible with (1), as:

* Except from the device status, the gdm72xx driver uses two more types
of messages (connection and OMA status), which is not supported
by wimax.h.

* The gdm driver needs to be able to receive status messages from
userspace, which is not supported by wimax.h either.

I therefore consider using the wimax stack as defined in wimax.h for the
netlink part, but replacing the ioctl with a file under /sys/class/net/wm0/

My questions are whether the above location would be the right place for
that file, and, more importantly, whether this is a generally a valid
approach and not just an ugly workaround.

Thanks,

Michalis