cfg80211: return private regdom for self-managed devices

If a device has self-managed regulatory, insist on returning the wiphy
specific regdomain if a wiphy-idx is specified. The global regdomain is
meaningless for such devices.

Also add an attribute for self-managed devices, so usermode can
distinguish them as such.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Reviewed-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/uapi/linux/nl80211.h

@@ -261,6 +261,9 @@
  *	the regulatory core to help with compliance. A dump version of this API
  *	is now available which will returns the global regdomain as well as
  *	all private regdomains of present wiphys (for those that have it).
+ *	If a wiphy is self-managed (%NL80211_ATTR_WIPHY_SELF_MANAGED_REG), then
+ *	its private regdomain is the only valid one for it. The regulatory
+ *	core is not used to help with compliance in this case.
  * @NL80211_CMD_SET_REG: Set current regulatory domain. CRDA sends this command
  *	after being queried by the kernel. CRDA replies by sending a regulatory
  *	domain structure which consists of %NL80211_ATTR_REG_ALPHA set to our
@@ -1702,6 +1705,11 @@ enum nl80211_commands {
  *
  * @NL80211_ATTR_MAC_MASK: MAC address mask
  *
+ * @NL80211_ATTR_WIPHY_SELF_MANAGED_REG: flag attribute indicating this device
+ *	is self-managing its regulatory information and any regulatory domain
+ *	obtained from it is coming from the device's wiphy and not the global
+ *	cfg80211 regdomain.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -2059,6 +2067,8 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_MAC_MASK,
 
+	NL80211_ATTR_WIPHY_SELF_MANAGED_REG,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,