Re: [PATCH v2 4/4] cfg80211: Allow usermode to query wiphy specific regd info

["Luis R. Rodriguez" <mcgrof@suse.com>]

On Fri, Nov 21, 2014 at 11:33:43AM +0200, Arik Nemtsov wrote:
> On Thu, Nov 20, 2014 at 10:54 PM, Luis R. Rodriguez <mcgrof@suse.com> wrote:
> >>
> >> Then it gets the global one, and it knows it via a wiphy attribute:
> >>
> >>       (wiphy->regulatory_flags & REGULATORY_WIPHY_SELF_MANAGED) &&
> >> +                   (nla_put_flag(msg, NL80211_ATTR_WIPHY_SELF_MANAGED_REG)))
> >> +                       goto nla_put_failure;
> >>
> >> (we won't do this put_flag if it's global)
> >
> > You can still follow this on wpa_s for REGULATORY_WIPHY_SELF_MANAGED, and
> > the other type that uses wiphy->regd would still follow the global regdomain.
> > The other flag I'm looking for is more informational for userspace in particular
> > 'iw reg get' (for central and all devices) or 'iw reg get dev wlan0'.
> 
> I'm not sure why another flag is needed for userspace.

wiphy->regd will be used for REGULATORY_WIPHY_SELF_MANAGED and also on
devices that regulatory_hint() is called. Even though users of regulatory_hint()
will still abide by an intersection its useful to display that device's
regulatory domain in userspace, for that you'd need to distinguish it from
REGULATORY_WIPHY_SELF_MANAGED so another flag is needed. Showing that
regulatory domain will be informational.

> If we have
> SELF_MANAGED, we'll return the per-wiphy one (if a wiphy_idx is given
> to us of course). For validation purposes, the global one is used in
> other cases. And for CUSTOM_REG, we'll return the global one (we don't
> have the per-wiphy information in cfg80211).

Atheros cards always use CUSTOM_REG first, then later if they determine
the card was programmed with an alpha2 regulatory_hint() is called and
the CUSTOM_REG flag cleared. Regardless if wiphy->regd is set it would
be useful to have that information available.

  Luis