mac80211: redefine usage of the mac80211 workqueue

The mac80211 workqueue exists to enable mac80211 and drivers
to queue their own work on a single threaded workqueue. mac80211
takes care to flush the workqueue during suspend but we never
really had requirements on drivers for how they should use
the workqueue in consideration for suspend.

We extend mac80211 to document how the mac80211 workqueue should
be used, how it should not be used and finally move raw access to
the workqueue to mac80211 only. Drivers and mac80211 use helpers
to queue work onto the mac80211 workqueue:

  * ieee80211_queue_work()
  * ieee80211_queue_delayed_work()

These helpers will now warn if mac80211 already completed its
suspend cycle and someone is trying to queue work. mac80211
flushes the mac80211 workqueue prior to suspend a few times,
but we haven't taken the care to ensure drivers won't add more
work after suspend. To help with this we add a warning when
someone tries to add work and mac80211 already completed the
suspend cycle.

Drivers should ensure they cancel any work or delayed work
in the mac80211 stop() callback.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 6 insertions, 6 deletions

diff --git a/drivers/net/wireless/b43/main.c b/drivers/net/wireless/b43/main.c
index 3f4360ad0e4..f985938962e 100644
--- a/drivers/net/wireless/b43/main.c
+++ b/drivers/net/wireless/b43/main.c
@@ -1654,7 +1654,7 @@ static void b43_update_templates(struct b43_wl *wl)
         wl->current_beacon = beacon;
         wl->beacon0_uploaded = 0;
         wl->beacon1_uploaded = 0;
-        queue_work(wl->hw->workqueue, &wl->beacon_update_trigger);
+        ieee80211_queue_work(wl->hw, &wl->beacon_update_trigger);
 }
 
 static void b43_set_beacon_int(struct b43_wldev *dev, u16 beacon_int)
@@ -2914,7 +2914,7 @@ out_requeue:
                 delay = msecs_to_jiffies(50);
         else
                 delay = round_jiffies_relative(HZ * 15);
-        queue_delayed_work(wl->hw->workqueue, &dev->periodic_work, delay);
+        ieee80211_queue_delayed_work(wl->hw, &dev->periodic_work, delay);
 out:
         mutex_unlock(&wl->mutex);
 }
@@ -2925,7 +2925,7 @@ static void b43_periodic_tasks_setup(struct b43_wldev *dev)
 
         dev->periodic_state = 0;
         INIT_DELAYED_WORK(work, b43_periodic_work_handler);
-        queue_delayed_work(dev->wl->hw->workqueue, work, 0);
+        ieee80211_queue_delayed_work(dev->wl->hw, work, 0);
 }
 
 /* Check if communication with the device works correctly. */
@@ -4871,7 +4871,7 @@ void b43_controller_restart(struct b43_wldev *dev, const char *reason)
         if (b43_status(dev) < B43_STAT_INITIALIZED)
                 return;
         b43info(dev->wl, "Controller RESET (%s) ...\n", reason);
-        queue_work(dev->wl->hw->workqueue, &dev->restart_work);
+        ieee80211_queue_work(dev->wl->hw, &dev->restart_work);
 }
 
 #ifdef CONFIG_PM
diff --git a/drivers/net/wireless/b43/phy_common.c b/drivers/net/wireless/b43/phy_common.c
index 6d241622210..f537bfef690 100644
--- a/drivers/net/wireless/b43/phy_common.c
+++ b/drivers/net/wireless/b43/phy_common.c
@@ -352,7 +352,7 @@ void b43_phy_txpower_check(struct b43_wldev *dev, unsigned int flags)
 
         /* We must adjust the transmission power in hardware.
          * Schedule b43_phy_txpower_adjust_work(). */
-        queue_work(dev->wl->hw->workqueue, &dev->wl->txpower_adjust_work);
+        ieee80211_queue_work(dev->wl->hw, &dev->wl->txpower_adjust_work);
 }
 
 int b43_phy_shm_tssi_read(struct b43_wldev *dev, u16 shm_offset)
diff --git a/drivers/net/wireless/b43/pio.c b/drivers/net/wireless/b43/pio.c
index 69138e8c1db..73c047d8de4 100644
--- a/drivers/net/wireless/b43/pio.c
+++ b/drivers/net/wireless/b43/pio.c
@@ -783,7 +783,7 @@ void b43_pio_rx(struct b43_pio_rxqueue *q)
 {
         /* Due to latency issues we must run the RX path in
          * a workqueue to be able to schedule between packets. */
-        queue_work(q->dev->wl->hw->workqueue, &q->rx_work);
+        ieee80211_queue_work(q->dev->wl->hw, &q->rx_work);
 }
 
 static void b43_pio_tx_suspend_queue(struct b43_pio_txqueue *q)