iwlwifi: extend notification wait

Sometimes, for example when we ask the uCode
for calibration, we wait for the "complete"
response while we also need the results that
are sent in other, interim, notifications.

Currently we handle this by installing an RX
handler globally, but that isn't needed as
this is the only time we want to use these
notifications.

So in order to be able to simplify at least
future code that does the same, extend the
notification wait framework to allow you to
wait for multiple commands and decide based
on the command whether the wait finished.

While at it, also fix a race that can then
become relevant -- if the wait function has
returned true once it shouldn't be called
again, today this can happen due to races
between the triggering and the wakeup.

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, 15 insertions, 6 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-notif-wait.h b/drivers/net/wireless/iwlwifi/iwl-notif-wait.h
index 5e8af95..82152310 100644
--- a/drivers/net/wireless/iwlwifi/iwl-notif-wait.h
+++ b/drivers/net/wireless/iwlwifi/iwl-notif-wait.h
@@ -72,11 +72,19 @@ struct iwl_notif_wait_data {
 	wait_queue_head_t notif_waitq;
 };
 
+#define MAX_NOTIF_CMDS	5
+
 /**
  * struct iwl_notification_wait - notification wait entry
  * @list: list head for global list
- * @fn: function called with the notification
- * @cmd: command ID
+ * @fn: Function called with the notification. If the function
+ *	returns true, the wait is over, if it returns false then
+ *	the waiter stays blocked. If no function is given, any
+ *	of the listed commands will unblock the waiter.
+ * @cmds: command IDs
+ * @n_cmds: number of command IDs
+ * @triggered: waiter should be woken up
+ * @aborted: wait was aborted
  *
  * This structure is not used directly, to wait for a
  * notification declare it on the stack, and call
@@ -93,11 +101,12 @@ struct iwl_notif_wait_data {
 struct iwl_notification_wait {
 	struct list_head list;
 
-	void (*fn)(struct iwl_notif_wait_data *notif_data,
+	bool (*fn)(struct iwl_notif_wait_data *notif_data,
 		   struct iwl_rx_packet *pkt, void *data);
 	void *fn_data;
 
-	u8 cmd;
+	u8 cmds[MAX_NOTIF_CMDS];
+	u8 n_cmds;
 	bool triggered, aborted;
 };
 
@@ -112,8 +121,8 @@ void iwl_abort_notification_waits(struct iwl_notif_wait_data *notif_data);
 void __acquires(wait_entry)
 iwl_init_notification_wait(struct iwl_notif_wait_data *notif_data,
 			   struct iwl_notification_wait *wait_entry,
-			   u8 cmd,
-			   void (*fn)(struct iwl_notif_wait_data *notif_data,
+			   const u8 *cmds, int n_cmds,
+			   bool (*fn)(struct iwl_notif_wait_data *notif_data,
 				      struct iwl_rx_packet *pkt, void *data),
 			   void *fn_data);