ath9k_hw: use a software timer for btcoex no_stomp_timer

TSF accuracy is not needed here, and there is only one usable generic
timer that is supported by all chips and uses the primary TSF counter.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 15 insertions, 47 deletions

diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index 5e5d5cb2458c..dbf2a97d4daa 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -477,20 +477,19 @@ enum bt_op_flags {
 };
 
 struct ath_btcoex {
-        bool hw_timer_enabled;
         spinlock_t btcoex_lock;
         struct timer_list period_timer; /* Timer for BT period */
+        struct timer_list no_stomp_timer;
         u32 bt_priority_cnt;
         unsigned long bt_priority_time;
         unsigned long op_flags;
         int bt_stomp_type; /* Types of BT stomping */
-        u32 btcoex_no_stomp; /* in usec */
+        u32 btcoex_no_stomp; /* in msec */
         u32 btcoex_period; /* in msec */
-        u32 btscan_no_stomp; /* in usec */
+        u32 btscan_no_stomp; /* in msec */
         u32 duty_cycle;
         u32 bt_wait_time;
         int rssi_count;
-        struct ath_gen_timer *no_stomp_timer; /* Timer for no BT stomping */
         struct ath_mci_profile mci;
         u8 stomp_audio;
 };
diff --git a/drivers/net/wireless/ath/ath9k/gpio.c b/drivers/net/wireless/ath/ath9k/gpio.c
index c34f21241da9..a85e220c8d9c 100644
--- a/drivers/net/wireless/ath/ath9k/gpio.c
+++ b/drivers/net/wireless/ath/ath9k/gpio.c
@@ -257,19 +257,9 @@ static void ath_btcoex_period_timer(unsigned long data)
 
         spin_unlock_bh(&btcoex->btcoex_lock);
 
-        /*
-         * btcoex_period is in msec while (btocex/btscan_)no_stomp are in usec,
-         * ensure that we properly convert btcoex_period to usec
-         * for any comparision with (btcoex/btscan_)no_stomp.
-         */
-        if (btcoex->btcoex_period * 1000 != btcoex->btcoex_no_stomp) {
-                if (btcoex->hw_timer_enabled)
-                        ath9k_gen_timer_stop(ah, btcoex->no_stomp_timer);
-
-                ath9k_gen_timer_start(ah, btcoex->no_stomp_timer, timer_period,
-                                      timer_period * 10);
-                btcoex->hw_timer_enabled = true;
-        }
+        if (btcoex->btcoex_period != btcoex->btcoex_no_stomp)
+                mod_timer(&btcoex->no_stomp_timer,
+                         jiffies + msecs_to_jiffies(timer_period));
 
         ath9k_ps_restore(sc);
 
@@ -282,7 +272,7 @@ skip_hw_wakeup:
  * Generic tsf based hw timer which configures weight
  * registers to time slice between wlan and bt traffic
  */
-static void ath_btcoex_no_stomp_timer(void *arg)
+static void ath_btcoex_no_stomp_timer(unsigned long arg)
 {
         struct ath_softc *sc = (struct ath_softc *)arg;
         struct ath_hw *ah = sc->sc_ah;
@@ -311,24 +301,18 @@ static int ath_init_btcoex_timer(struct ath_softc *sc)
         struct ath_btcoex *btcoex = &sc->btcoex;
 
         btcoex->btcoex_period = ATH_BTCOEX_DEF_BT_PERIOD;
-        btcoex->btcoex_no_stomp = (100 - ATH_BTCOEX_DEF_DUTY_CYCLE) * 1000 *
+        btcoex->btcoex_no_stomp = (100 - ATH_BTCOEX_DEF_DUTY_CYCLE) *
                 btcoex->btcoex_period / 100;
-        btcoex->btscan_no_stomp = (100 - ATH_BTCOEX_BTSCAN_DUTY_CYCLE) * 1000 *
+        btcoex->btscan_no_stomp = (100 - ATH_BTCOEX_BTSCAN_DUTY_CYCLE) *
                                    btcoex->btcoex_period / 100;
 
         setup_timer(&btcoex->period_timer, ath_btcoex_period_timer,
                         (unsigned long) sc);
+        setup_timer(&btcoex->no_stomp_timer, ath_btcoex_no_stomp_timer,
+                        (unsigned long) sc);
 
         spin_lock_init(&btcoex->btcoex_lock);
 
-        btcoex->no_stomp_timer = ath_gen_timer_alloc(sc->sc_ah,
-                        ath_btcoex_no_stomp_timer,
-                        ath_btcoex_no_stomp_timer,
-                        (void *) sc, AR_FIRST_NDP_TIMER);
-
-        if (!btcoex->no_stomp_timer)
-                return -ENOMEM;
-
         return 0;
 }
 
@@ -343,10 +327,7 @@ void ath9k_btcoex_timer_resume(struct ath_softc *sc)
         ath_dbg(ath9k_hw_common(ah), BTCOEX, "Starting btcoex timers\n");
 
         /* make sure duty cycle timer is also stopped when resuming */
-        if (btcoex->hw_timer_enabled) {
-                ath9k_gen_timer_stop(sc->sc_ah, btcoex->no_stomp_timer);
-                btcoex->hw_timer_enabled = false;
-        }
+        del_timer_sync(&btcoex->no_stomp_timer);
 
         btcoex->bt_priority_cnt = 0;
         btcoex->bt_priority_time = jiffies;
@@ -363,24 +344,16 @@ void ath9k_btcoex_timer_resume(struct ath_softc *sc)
 void ath9k_btcoex_timer_pause(struct ath_softc *sc)
 {
         struct ath_btcoex *btcoex = &sc->btcoex;
-        struct ath_hw *ah = sc->sc_ah;
 
         del_timer_sync(&btcoex->period_timer);
-
-        if (btcoex->hw_timer_enabled) {
-                ath9k_gen_timer_stop(ah, btcoex->no_stomp_timer);
-                btcoex->hw_timer_enabled = false;
-        }
+        del_timer_sync(&btcoex->no_stomp_timer);
 }
 
 void ath9k_btcoex_stop_gen_timer(struct ath_softc *sc)
 {
         struct ath_btcoex *btcoex = &sc->btcoex;
 
-        if (btcoex->hw_timer_enabled) {
-                ath9k_gen_timer_stop(sc->sc_ah, btcoex->no_stomp_timer);
-                btcoex->hw_timer_enabled = false;
-        }
+        del_timer_sync(&btcoex->no_stomp_timer);
 }
 
 u16 ath9k_btcoex_aggr_limit(struct ath_softc *sc, u32 max_4ms_framelen)
@@ -447,10 +420,6 @@ void ath9k_deinit_btcoex(struct ath_softc *sc)
 {
         struct ath_hw *ah = sc->sc_ah;
 
-        if ((sc->btcoex.no_stomp_timer) &&
-            ath9k_hw_get_btcoex_scheme(sc->sc_ah) == ATH_BTCOEX_CFG_3WIRE)
-                ath_gen_timer_free(sc->sc_ah, sc->btcoex.no_stomp_timer);
-
         if (ath9k_hw_mci_is_enabled(ah))
                 ath_mci_cleanup(sc);
 }
diff --git a/drivers/net/wireless/ath/ath9k/mci.c b/drivers/net/wireless/ath/ath9k/mci.c
index 0ac1b5f04256..71799fcade54 100644
--- a/drivers/net/wireless/ath/ath9k/mci.c
+++ b/drivers/net/wireless/ath/ath9k/mci.c
@@ -200,7 +200,7 @@ skip_tuning:
         if (btcoex->duty_cycle > ATH_MCI_MAX_DUTY_CYCLE)
                 btcoex->duty_cycle = ATH_MCI_MAX_DUTY_CYCLE;
 
-        btcoex->btcoex_no_stomp =  btcoex->btcoex_period * 1000 *
+        btcoex->btcoex_no_stomp =  btcoex->btcoex_period *
                 (100 - btcoex->duty_cycle) / 100;
 
         ath9k_hw_btcoex_enable(sc->sc_ah);