mac80211: add device_timestamp to the ieee80211_channel_switch struct

Some devices may need the device timestamp in order to synchronize the
channel switch.  To pass this value back to the driver, add it to the
channel switch structure and copy the device_timestamp value received
in the rx info structure into it.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 0ad1f47..ec0a5b0 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1117,6 +1117,8 @@
  *	Function (TSF) timer when the frame containing the channel switch
  *	announcement was received. This is simply the rx.mactime parameter
  *	the driver passed into mac80211.
+ * @device_timestamp: arbitrary timestamp for the device, this is the
+ *	rx.device_timestamp parameter the driver passed to mac80211.
  * @block_tx: Indicates whether transmission must be blocked before the
  *	scheduled channel switch, as indicated by the AP.
  * @chandef: the new channel to switch to
@@ -1124,6 +1126,7 @@
  */
 struct ieee80211_channel_switch {
 	u64 timestamp;
+	u32 device_timestamp;
 	bool block_tx;
 	struct cfg80211_chan_def chandef;
 	u8 count;