mac80211: Handle power constraint level advertised in 11d+h beacon

This patch uses power constraint level while determining the maximum
transmit power, there by it makes sure that any power mitigation
requirement for the channel in the current regulatory domain is met.

Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 21 insertions, 0 deletions

diff --git a/net/mac80211/spectmgmt.c b/net/mac80211/spectmgmt.c
index 8396b5a77e8d..8d4ec2968f8f 100644
--- a/net/mac80211/spectmgmt.c
+++ b/net/mac80211/spectmgmt.c
@@ -161,3 +161,24 @@ void ieee80211_process_chanswitch(struct ieee80211_sub_if_data *sdata,
                           jiffies + msecs_to_jiffies(sw_elem->count * bss->beacon_int));
         }
 }
+
+void ieee80211_handle_pwr_constr(struct ieee80211_sub_if_data *sdata,
+                                 u16 capab_info, u8 *pwr_constr_elem,
+                                 u8 pwr_constr_elem_len)
+{
+        struct ieee80211_conf *conf = &sdata->local->hw.conf;
+
+        if (!(capab_info & WLAN_CAPABILITY_SPECTRUM_MGMT))
+                return;
+
+        /* Power constraint IE length should be 1 octet */
+        if (pwr_constr_elem_len != 1)
+                return;
+
+        if ((*pwr_constr_elem <= conf->channel->max_power) &&
+            (*pwr_constr_elem != sdata->local->power_constr_level)) {
+                sdata->local->power_constr_level = *pwr_constr_elem;
+                ieee80211_hw_config(sdata->local, 0);
+        }
+}
+