mac80211: enable TPC through mac80211 stack

Control per packet Transmit Power Control (TPC) in lower drivers
according to TX power settings configured by the user. In particular TPC is
enabled if value passed in enum nl80211_tx_power_setting is
NL80211_TX_POWER_LIMITED (allow using less than specified from userspace),
whereas TPC is disabled if nl80211_tx_power_setting is set to
NL80211_TX_POWER_FIXED (use value configured from userspace)

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 33b87c5..866073e 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -376,6 +376,12 @@
  * @ssid_len: Length of SSID given in @ssid.
  * @hidden_ssid: The SSID of the current vif is hidden. Only valid in AP-mode.
  * @txpower: TX power in dBm
+ * @txpower_type: TX power adjustment used to control per packet Transmit
+ *	Power Control (TPC) in lower driver for the current vif. In particular
+ *	TPC is enabled if value passed in %txpower_type is
+ *	NL80211_TX_POWER_LIMITED (allow using less than specified from
+ *	userspace), whereas TPC is disabled if %txpower_type is set to
+ *	NL80211_TX_POWER_FIXED (use value configured from userspace)
  * @p2p_noa_attr: P2P NoA attribute for P2P powersave
  */
 struct ieee80211_bss_conf {
@@ -411,6 +417,7 @@
 	size_t ssid_len;
 	bool hidden_ssid;
 	int txpower;
+	enum nl80211_tx_power_setting txpower_type;
 	struct ieee80211_p2p_noa_attr p2p_noa_attr;
 };