ath10k: implement device recovery

Restart the hardware if FW crashes.

If FW crashes during recovery we leave the
hardware in a "wedged" state to avoid recursive
recoveries.

When in "wedged" state userspace may bring
interfaces down (to issue stop()) and then bring
one interface (to issue start()) to reload
hardware manually.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/drivers/net/wireless/ath/ath10k/wmi.c b/drivers/net/wireless/ath/ath10k/wmi.c
index b7e7e456b5de..0d25cd733afd 100644
--- a/drivers/net/wireless/ath/ath10k/wmi.c
+++ b/drivers/net/wireless/ath/ath10k/wmi.c
@@ -27,6 +27,13 @@ void ath10k_wmi_flush_tx(struct ath10k *ar)
 {
         int ret;
 
+        lockdep_assert_held(&ar->conf_mutex);
+
+        if (ar->state == ATH10K_STATE_WEDGED) {
+                ath10k_warn("wmi flush skipped - device is wedged anyway\n");
+                return;
+        }
+
         ret = wait_event_timeout(ar->wmi.wq,
                                  atomic_read(&ar->wmi.pending_tx_count) == 0,
                                  5*HZ);