[source] ath10k: fix a soft-lockup on firmware restart

[LEDE Commits]

nbd pushed a commit to source.git, branch master:
https://git.lede-project.org/28f6951600d0da31363e9b17dbad3f47097f4104

commit 28f6951600d0da31363e9b17dbad3f47097f4104
Author: Felix Fietkau <nbd at nbd.name>
AuthorDate: Tue Dec 13 12:52:16 2016 +0100

    ath10k: fix a soft-lockup on firmware restart
    
    Signed-off-by: Felix Fietkau <nbd at nbd.name>
---
 ...soft-lockup-during-firmware-crash-hw-rest.patch | 49 ++++++++++++++++++++++
 .../patches/930-ath10k_add_tpt_led_trigger.patch   |  4 +-
 2 files changed, 51 insertions(+), 2 deletions(-)

diff --git a/package/kernel/mac80211/patches/333-ath10k-Fix-soft-lockup-during-firmware-crash-hw-rest.patch b/package/kernel/mac80211/patches/333-ath10k-Fix-soft-lockup-during-firmware-crash-hw-rest.patch
new file mode 100644
index 0000000..89ff1fc
--- /dev/null
+++ b/package/kernel/mac80211/patches/333-ath10k-Fix-soft-lockup-during-firmware-crash-hw-rest.patch
@@ -0,0 +1,49 @@
+From: Mohammed Shafi Shajakhan <mohammed at qti.qualcomm.com>
+Date: Wed, 30 Nov 2016 10:59:29 +0530
+Subject: [PATCH] ath10k: Fix soft lockup during firmware crash/hw-restart
+
+During firmware crash (or) user requested manual restart
+the system gets into a soft lock up state because of the
+below root cause.
+
+During user requested hardware restart / firmware crash
+the system goes into a soft lockup state as 'napi_synchronize'
+is called after 'napi_disable' (which sets 'NAPI_STATE_SCHED'
+bit) and it sleeps into infinite loop as it waits for
+'NAPI_STATE_SCHED' to be cleared. This condition is hit because
+'ath10k_hif_stop' is called twice as below (resulting in calling
+'napi_synchronize' after 'napi_disable')
+
+'ath10k_core_restart' -> 'ath10k_hif_stop' (ATH10K_STATE_ON) ->
+-> 'ieee80211_restart_hw' -> 'ath10k_start' -> 'ath10k_halt' ->
+'ath10k_core_stop' -> 'ath10k_hif_stop' (ATH10K_STATE_RESTARTING)
+
+Fix this by calling 'ath10k_halt' in ath10k_core_restart itself
+as it makes more sense before informing mac80211 to restart h/w
+Also remove 'ath10k_halt' in ath10k_start for the state of 'restarting'
+
+Fixes: 3c97f5de1f28 ("ath10k: implement NAPI support")
+Signed-off-by: Mohammed Shafi Shajakhan <mohammed at qti.qualcomm.com>
+---
+
+--- a/drivers/net/wireless/ath/ath10k/core.c
++++ b/drivers/net/wireless/ath/ath10k/core.c
+@@ -1534,7 +1534,7 @@ static void ath10k_core_restart(struct w
+ 	switch (ar->state) {
+ 	case ATH10K_STATE_ON:
+ 		ar->state = ATH10K_STATE_RESTARTING;
+-		ath10k_hif_stop(ar);
++		ath10k_halt(ar);
+ 		ath10k_scan_finish(ar);
+ 		ieee80211_restart_hw(ar->hw);
+ 		break;
+--- a/drivers/net/wireless/ath/ath10k/mac.c
++++ b/drivers/net/wireless/ath/ath10k/mac.c
+@@ -4470,7 +4470,6 @@ static int ath10k_start(struct ieee80211
+ 		ar->state = ATH10K_STATE_ON;
+ 		break;
+ 	case ATH10K_STATE_RESTARTING:
+-		ath10k_halt(ar);
+ 		ar->state = ATH10K_STATE_RESTARTED;
+ 		break;
+ 	case ATH10K_STATE_ON:
diff --git a/package/kernel/mac80211/patches/930-ath10k_add_tpt_led_trigger.patch b/package/kernel/mac80211/patches/930-ath10k_add_tpt_led_trigger.patch
index 3177c81..d47e2a6 100644
--- a/package/kernel/mac80211/patches/930-ath10k_add_tpt_led_trigger.patch
+++ b/package/kernel/mac80211/patches/930-ath10k_add_tpt_led_trigger.patch
@@ -1,6 +1,6 @@
 --- a/drivers/net/wireless/ath/ath10k/mac.c
 +++ b/drivers/net/wireless/ath/ath10k/mac.c
-@@ -7815,6 +7815,21 @@ struct ath10k_vif *ath10k_get_arvif(stru
+@@ -7812,6 +7812,21 @@ struct ath10k_vif *ath10k_get_arvif(stru
  	return arvif_iter.arvif;
  }
  
@@ -22,7 +22,7 @@
  int ath10k_mac_register(struct ath10k *ar)
  {
  	static const u32 cipher_suites[] = {
-@@ -8048,6 +8063,12 @@ int ath10k_mac_register(struct ath10k *a
+@@ -8045,6 +8060,12 @@ int ath10k_mac_register(struct ath10k *a
  	ar->hw->wiphy->cipher_suites = cipher_suites;
  	ar->hw->wiphy->n_cipher_suites = ARRAY_SIZE(cipher_suites);