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>
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index e33fe79..120f102 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1708,6 +1708,14 @@
* 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 @@
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,
diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h
index eebf7a6..0e7e426 100644
--- a/net/mac80211/driver-ops.h
+++ b/net/mac80211/driver-ops.h
@@ -218,6 +218,16 @@
return ret;
}
+static inline void drv_cancel_hw_scan(struct ieee80211_local *local,
+ struct ieee80211_sub_if_data *sdata)
+{
+ might_sleep();
+
+ trace_drv_cancel_hw_scan(local, sdata);
+ local->ops->cancel_hw_scan(&local->hw, &sdata->vif);
+ trace_drv_return_void(local);
+}
+
static inline int
drv_sched_scan_start(struct ieee80211_local *local,
struct ieee80211_sub_if_data *sdata,
diff --git a/net/mac80211/driver-trace.h b/net/mac80211/driver-trace.h
index ed9edcb..3cb6795 100644
--- a/net/mac80211/driver-trace.h
+++ b/net/mac80211/driver-trace.h
@@ -460,6 +460,12 @@
TP_ARGS(local, sdata)
);
+DEFINE_EVENT(local_sdata_evt, drv_cancel_hw_scan,
+ TP_PROTO(struct ieee80211_local *local,
+ struct ieee80211_sub_if_data *sdata),
+ TP_ARGS(local, sdata)
+);
+
DEFINE_EVENT(local_sdata_evt, drv_sched_scan_start,
TP_PROTO(struct ieee80211_local *local,
struct ieee80211_sub_if_data *sdata),
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index 58ffa7d..1758b46 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -821,10 +821,8 @@
*/
void ieee80211_scan_cancel(struct ieee80211_local *local)
{
- bool abortscan;
-
/*
- * We are only canceling software scan, or deferred scan that was not
+ * We are canceling software scan, or deferred scan that was not
* yet really started (see __ieee80211_start_scan ).
*
* Regarding hardware scan:
@@ -836,23 +834,30 @@
* - we can not cancel scan_work since driver can schedule it
* by ieee80211_scan_completed(..., true) to finish scan
*
- * Hence low lever driver is responsible for canceling HW scan.
+ * Hence we only call the cancel_hw_scan() callback, but the low-level
+ * driver is still responsible for calling ieee80211_scan_completed()
+ * after the scan was completed/aborted.
*/
mutex_lock(&local->mtx);
- abortscan = local->scan_req && !test_bit(SCAN_HW_SCANNING, &local->scanning);
- if (abortscan) {
- /*
- * The scan is canceled, but stop work from being pending.
- *
- * If the work is currently running, it must be blocked on
- * the mutex, but we'll set scan_sdata = NULL and it'll
- * simply exit once it acquires the mutex.
- */
- cancel_delayed_work(&local->scan_work);
- /* and clean up */
- __ieee80211_scan_completed(&local->hw, true, false);
+ if (!local->scan_req)
+ goto out;
+
+ if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
+ if (local->ops->cancel_hw_scan)
+ drv_cancel_hw_scan(local, local->scan_sdata);
+ goto out;
}
+
+ /*
+ * If the work is currently running, it must be blocked on
+ * the mutex, but we'll set scan_sdata = NULL and it'll
+ * simply exit once it acquires the mutex.
+ */
+ cancel_delayed_work(&local->scan_work);
+ /* and clean up */
+ __ieee80211_scan_completed(&local->hw, true, false);
+out:
mutex_unlock(&local->mtx);
}