iwlagn: add support for waiting for notifications

In order to implement waiting for notifications,
add a structure that captures the information,
and a list of such structures that will be
traversed when a command is received from the
ucode.

Use sparse checking to make sure calls to the
prepare/wait/cancel functions are always nested
correctly.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 46 insertions, 0 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-agn-lib.c b/drivers/net/wireless/iwlwifi/iwl-agn-lib.c
index 3dee87e8f55..29dcda0bde6 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn-lib.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn-lib.c
@@ -473,6 +473,11 @@ void iwlagn_rx_handler_setup(struct iwl_priv *priv)
 	priv->rx_handlers[CALIBRATION_COMPLETE_NOTIFICATION] =
 					iwlagn_rx_calib_complete;
 	priv->rx_handlers[REPLY_TX] = iwlagn_rx_reply_tx;
+
+	/* set up notification wait support */
+	spin_lock_init(&priv->_agn.notif_wait_lock);
+	INIT_LIST_HEAD(&priv->_agn.notif_waits);
+	init_waitqueue_head(&priv->_agn.notif_waitq);
 }
 
 void iwlagn_setup_deferred_work(struct iwl_priv *priv)
@@ -2389,3 +2394,44 @@ int iwl_dump_fh(struct iwl_priv *priv, char **buf, bool display)
 	}
 	return 0;
 }
+
+/* notification wait support */
+void iwlagn_init_notification_wait(struct iwl_priv *priv,
+				   struct iwl_notification_wait *wait_entry,
+				   void (*fn)(struct iwl_priv *priv,
+					      struct iwl_rx_packet *pkt),
+				   u8 cmd)
+{
+	wait_entry->fn = fn;
+	wait_entry->cmd = cmd;
+	wait_entry->triggered = false;
+
+	spin_lock_bh(&priv->_agn.notif_wait_lock);
+	list_add(&wait_entry->list, &priv->_agn.notif_waits);
+	spin_unlock_bh(&priv->_agn.notif_wait_lock);
+}
+
+signed long iwlagn_wait_notification(struct iwl_priv *priv,
+				     struct iwl_notification_wait *wait_entry,
+				     unsigned long timeout)
+{
+	int ret;
+
+	ret = wait_event_timeout(priv->_agn.notif_waitq,
+				 &wait_entry->triggered,
+				 timeout);
+
+	spin_lock_bh(&priv->_agn.notif_wait_lock);
+	list_del(&wait_entry->list);
+	spin_unlock_bh(&priv->_agn.notif_wait_lock);
+
+	return ret;
+}
+
+void iwlagn_remove_notification(struct iwl_priv *priv,
+				struct iwl_notification_wait *wait_entry)
+{
+	spin_lock_bh(&priv->_agn.notif_wait_lock);
+	list_del(&wait_entry->list);
+	spin_unlock_bh(&priv->_agn.notif_wait_lock);
+}