nl80211: Add new WIPHY attribute COVERAGE_CLASS

The new attribute NL80211_ATTR_WIPHY_COVERAGE_CLASS sets IEEE 802.11
Coverage Class, which depends on maximum distance of nodes in a
wireless network. It's required for long distance links (more than a few
hundred meters).

The attribute is now ignored by two non-mac80211 drivers, rndis and
iwmc3200wifi, together with WIPHY_PARAM_RETRY_SHORT and
WIPHY_PARAM_RETRY_LONG. If it turns out to be a problem, we could split
set_wiphy_params callback or add new capability bits.

Signed-off-by: Lukas Turek <8an@praha12.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index 2bfbe88..d4c556d 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -430,6 +430,8 @@
  * @NL80211_ATTR_WIPHY_RTS_THRESHOLD: RTS threshold (TX frames with length
  *	larger than or equal to this use RTS/CTS handshake); allowed range:
  *	0..65536, disable with (u32)-1; dot11RTSThreshold; u32
+ * @NL80211_ATTR_WIPHY_COVERAGE_CLASS: Coverage Class as defined by IEEE 802.11
+ *	section 7.3.2.9; dot11CoverageClass; u8
  *
  * @NL80211_ATTR_IFINDEX: network interface index of the device to operate on
  * @NL80211_ATTR_IFNAME: network interface name
@@ -779,6 +781,8 @@
 
 	NL80211_ATTR_COOKIE,
 
+	NL80211_ATTR_WIPHY_COVERAGE_CLASS,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,