mac80211: add cancel_hw_scan() callback

When suspending, __ieee80211_suspend() calls ieee80211_scan_cancel(),
which will only cancel sw scan. In order to cancel hw scan, the
low-level driver has to cancel it in the suspend() callback. however,
this is too late, as a new scan_work will be enqueued (while the driver
is going into suspend).

Add a new cancel_hw_scan() callback, asking the driver to cancel an
active hw scan, and call it in ieee80211_scan_cancel().

Signed-off-by: Eliad Peller <eliad@wizery.com>
Reviewed-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index e33fe795a3a4..120f102814b6 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1708,6 +1708,14 @@ enum ieee80211_ampdu_mlme_action {
  *	any error unless this callback returned a negative error code.
  *	The callback can sleep.
  *
+ * @cancel_hw_scan: Ask the low-level tp cancel the active hw scan.
+ *	The driver should ask the hardware to cancel the scan (if possible),
+ *	but the scan will be completed only after the driver will call
+ *	ieee80211_scan_completed().
+ *	This callback is needed for wowlan, to prevent enqueueing a new
+ *	scan_work after the low-level driver was already suspended.
+ *	The callback can sleep.
+ *
  * @sched_scan_start: Ask the hardware to start scanning repeatedly at
  *	specific intervals.  The driver must call the
  *	ieee80211_sched_scan_results() function whenever it finds results.
@@ -1900,6 +1908,8 @@ struct ieee80211_ops {
 				u32 iv32, u16 *phase1key);
 	int (*hw_scan)(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
 		       struct cfg80211_scan_request *req);
+	void (*cancel_hw_scan)(struct ieee80211_hw *hw,
+			       struct ieee80211_vif *vif);
 	int (*sched_scan_start)(struct ieee80211_hw *hw,
 				struct ieee80211_vif *vif,
 				struct cfg80211_sched_scan_request *req,