iwlwifi: pcie: allow the op_mode to freeze the stuck queue timer

This allows the op_mode to let the transport know that a
queue is currently frozen and that its timer should be
stopped.
When the queue is unfrozen, its timer should be set to
expire after the remainder of the timeout has elapsed.
This can be used when stations go to sleep. When a station
goes to sleep, the op_mode can freeze the timer so that the
queue will never be considered as stuck. When the station
wakes up, the queue will be unfrozen.
This is meant to avoid false positives that would happen if
a buggy station goes to sleep for a very long time. In case
we have a dedicated queue for this station (BA agreement)
and it goes to sleep for a very long time, the queue would
rightfully be stopped during all that time. In this case,
the stuck queue timer could fire and that would be a false
positive.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/net/wireless/iwlwifi/pcie/internal.h b/drivers/net/wireless/iwlwifi/pcie/internal.h
index cae0eb8835ce..01996c9d98a7 100644
--- a/drivers/net/wireless/iwlwifi/pcie/internal.h
+++ b/drivers/net/wireless/iwlwifi/pcie/internal.h
@@ -217,6 +217,8 @@ struct iwl_pcie_txq_scratch_buf {
  * @active: stores if queue is active
  * @ampdu: true if this queue is an ampdu queue for an specific RA/TID
  * @wd_timeout: queue watchdog timeout (jiffies) - per queue
+ * @frozen: tx stuck queue timer is frozen
+ * @frozen_expiry_remainder: remember how long until the timer fires
  *
  * A Tx queue consists of circular buffer of BDs (a.k.a. TFDs, transmit frame
  * descriptors) and required locking structures.
@@ -228,9 +230,11 @@ struct iwl_txq {
 	dma_addr_t scratchbufs_dma;
 	struct iwl_pcie_txq_entry *entries;
 	spinlock_t lock;
+	unsigned long frozen_expiry_remainder;
 	struct timer_list stuck_timer;
 	struct iwl_trans_pcie *trans_pcie;
 	bool need_update;
+	bool frozen;
 	u8 active;
 	bool ampdu;
 	unsigned long wd_timeout;