mac80211: pass dtim_period to low level driver

This patch adds the dtim_period in ieee80211_bss_conf, this allows the low
level driver to know the dtim_period, and to plan power save accordingly.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/include/linux/ieee80211.h b/include/linux/ieee80211.h
index a1630ba..7f4df7c 100644
--- a/include/linux/ieee80211.h
+++ b/include/linux/ieee80211.h
@@ -506,6 +506,19 @@
 	u8 count;
 } __attribute__ ((packed));
 
+/**
+ * struct ieee80211_tim
+ *
+ * This structure refers to "Traffic Indication Map information element"
+ */
+struct ieee80211_tim_ie {
+	u8 dtim_count;
+	u8 dtim_period;
+	u8 bitmap_ctrl;
+	/* variable size: 1 - 251 bytes */
+	u8 virtual_map[0];
+} __attribute__ ((packed));
+
 struct ieee80211_mgmt {
 	__le16 frame_control;
 	__le16 duration;