iwlwifi: rework iwl_scan_cancel_timeout

Since on timeout version of iwl_scan_cancel procedure we can sleep,
do not have to schedule abort_scan work to begin and perform scanning,
can do this directly. Also now, as we do not queue abort_scan from
restart work anymore, we can queue abort_scan to priv->workqueue.

Don't drop mutex when waiting for scan complete. Use STATUS_HW_SCAN bit
to check if scanning is currently pending, because STATUS_SCANNING will
be cleared only with priv->mutex taken.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Wey-Yi W Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 12 insertions, 13 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-scan.c b/drivers/net/wireless/iwlwifi/iwl-scan.c
index dbb07e8dfcd7..6d02f41e8caa 100644
--- a/drivers/net/wireless/iwlwifi/iwl-scan.c
+++ b/drivers/net/wireless/iwlwifi/iwl-scan.c
@@ -126,7 +126,7 @@ static void iwl_do_scan_abort(struct iwl_priv *priv)
 int iwl_scan_cancel(struct iwl_priv *priv)
 {
         IWL_DEBUG_SCAN(priv, "Queuing abort scan\n");
-        schedule_work(&priv->abort_scan);
+        queue_work(priv->workqueue, &priv->abort_scan);
         return 0;
 }
 EXPORT_SYMBOL(iwl_scan_cancel);
@@ -135,25 +135,24 @@ EXPORT_SYMBOL(iwl_scan_cancel);
  * iwl_scan_cancel_timeout - Cancel any currently executing HW scan
  * @ms: amount of time to wait (in milliseconds) for scan to abort
  *
- * NOTE: priv->mutex must be held before calling this function
  */
 int iwl_scan_cancel_timeout(struct iwl_priv *priv, unsigned long ms)
 {
-        unsigned long now = jiffies;
-        int ret;
+        unsigned long timeout = jiffies + msecs_to_jiffies(ms);
+
+        lockdep_assert_held(&priv->mutex);
 
-        ret = iwl_scan_cancel(priv);
-        if (ret && ms) {
-                mutex_unlock(&priv->mutex);
-                while (!time_after(jiffies, now + msecs_to_jiffies(ms)) &&
-                                test_bit(STATUS_SCANNING, &priv->status))
-                        msleep(1);
-                mutex_lock(&priv->mutex);
+        IWL_DEBUG_SCAN(priv, "Scan cancel timeout\n");
 
-                return test_bit(STATUS_SCANNING, &priv->status);
+        iwl_do_scan_abort(priv);
+
+        while (time_before_eq(jiffies, timeout)) {
+                if (!test_bit(STATUS_SCAN_HW, &priv->status))
+                        break;
+                msleep(20);
         }
 
-        return ret;
+        return test_bit(STATUS_SCAN_HW, &priv->status);
 }
 EXPORT_SYMBOL(iwl_scan_cancel_timeout);