Re: [PATCH] allow setting wiphy.perm_addr after driver probe

[Daniel Gimpelevich <daniel@gimpelevich.san-francisco.ca.us>]

On Mon, 2014-08-11 at 15:41 -0700, Marcel Holtmann wrote:
> what kind of hardware are you actually using here?
> 
It's ath9k on MIPS under OpenWrt.
> 
> Internally it might do that, but I do not see it exposing the
> NL80211_ATTR_MAC when you get the attributes for wiphy.

When wlan0 is created, it can be created with its own MAC irrespective
of the wiphy MAC. In OpenWrt, the wlan0 MAC can be supplied and assigned
to a netdev created on a specific wiphy identified by its MAC, and if
that cannot be predicted, there is no wlan0.

> So I am still saying that when you do NL80211_CMD_NEW_INTERFACE allow
> providing NL80211_ATTR_MAC to set the MAC address to be used. It might
> be useful that the wiphy exposes an attribute saying that it does not
> have a default MAC address, but that should be it. I do not like these
> magic 00:00:00:00:00:00 games. As I mentioned earlier, in Bluetooth we
> just deal with allowing the driver to set a flag that it does not have
> a valid address. And then the core takes care of dealing with it.
> 
An attribute saying there is no default MAC is helpful only if there is
a way to supply a new default to the wiphy.