Hi,
I can not comment on the merits of your patch. Unless I am missing
something, which may well be since I only spent a couple of minutes on
it, other device classes don't seem to provide a similar API, so I don't
know if or why it would make sense for hwmon. Maybe a driver which wants
to register a character device interface should do so independently of
hwmon.
The idea here is to sit in the same class directory as of hwmon. Devices
registered with this interface will have "dev" under, for example,
/sys/class/hwmon/hwmon0/dev. To do the same inside the driver will be
a bit more involved than a call.
In my opinion other classes should also have similar interfaces.
On the technical side, EXPORT_SYMBOL is missing.
I will take care of that.
Regards
Himanshu