mac802154: add synchronization handling

This patch adds synchronization handling in start and stop driver ops
calls. This patch is mostly grab from mac80211 which was introduced by
commit ea77f12f2cc0f31168f2e0259e65a22202ac4dc2 ("mac80211: remove
tasklet enable/disable"). This is to be sure that we don't run into same
issues.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

1 files changed, 7 insertions, 0 deletions

diff --git a/net/mac802154/driver-ops.h b/net/mac802154/driver-ops.h
index bb3ee03c1669..4b820cfeb538 100644
--- a/net/mac802154/driver-ops.h
+++ b/net/mac802154/driver-ops.h
@@ -30,6 +30,7 @@ static inline int drv_start(struct ieee802154_local *local)
         might_sleep();
 
         local->started = true;
+        smp_mb();
 
         return local->ops->start(&local->hw);
 }
@@ -40,6 +41,12 @@ static inline void drv_stop(struct ieee802154_local *local)
 
         local->ops->stop(&local->hw);
 
+        /* sync away all work on the tasklet before clearing started */
+        tasklet_disable(&local->tasklet);
+        tasklet_enable(&local->tasklet);
+
+        barrier();
+
         local->started = false;
 }