summaryrefslogtreecommitdiff
path: root/package/mac80211/patches/408-ath9k-serialize-ath9k_ps_-wakeup-restore-calls.patch
blob: 01318fb2f791f8adb315c3b73dbec61f1fd91bb3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
From 7446da6910f1368273a55ca99acba18828306a6e Mon Sep 17 00:00:00 2001
From: Gabor Juhos <juhosg@openwrt.org>
Date: Sun, 21 Jun 2009 16:59:53 +0200
Subject: [PATCH 3/3] ath9k: serialize ath9k_ps_{wakeup,restore} calls

These functions are changing the power mode of the chip, but this may
have unpredictable effects, if another code are trying to set the power
mode via 'ath9k_hw_setpower' in the same time from another context.

Changes-licensed-under: ISC
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
---
 drivers/net/wireless/ath/ath9k/ath9k.h |    2 +-
 drivers/net/wireless/ath/ath9k/hw.c    |   42 ++++++++++++++++++++++----------
 2 files changed, 30 insertions(+), 14 deletions(-)

--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -561,7 +561,7 @@ struct ath_softc {
 	u32 keymax;
 	DECLARE_BITMAP(keymap, ATH_KEYMAX);
 	u8 splitmic;
-	atomic_t ps_usecount;
+	unsigned long ps_usecount;
 	enum ath9k_int imask;
 	enum ath9k_ht_extprotspacing ht_extprotspacing;
 	enum ath9k_ht_macmode tx_chan_width;
--- a/drivers/net/wireless/ath/ath9k/hw.c
+++ b/drivers/net/wireless/ath/ath9k/hw.c
@@ -2787,23 +2787,39 @@ bool ath9k_hw_setpower(struct ath_hw *ah
 
 void ath9k_ps_wakeup(struct ath_softc *sc)
 {
-	if (atomic_inc_return(&sc->ps_usecount) == 1)
-		if (sc->sc_ah->power_mode != ATH9K_PM_AWAKE) {
-			sc->sc_ah->restore_mode = sc->sc_ah->power_mode;
-			ath9k_hw_setpower(sc->sc_ah, ATH9K_PM_AWAKE);
-		}
+	unsigned long flags;
+
+	spin_lock_irqsave(&sc->sc_pm_lock, flags);
+	if (++sc->ps_usecount != 1)
+		goto unlock;
+
+	if (sc->sc_ah->power_mode != ATH9K_PM_AWAKE) {
+		sc->sc_ah->restore_mode = sc->sc_ah->power_mode;
+		ath9k_hw_setpower_nolock(sc->sc_ah, ATH9K_PM_AWAKE);
+	}
+
+ unlock:
+	spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
 }
 
 void ath9k_ps_restore(struct ath_softc *sc)
 {
-	if (atomic_dec_and_test(&sc->ps_usecount))
-		if ((sc->hw->conf.flags & IEEE80211_CONF_PS) &&
-		    !(sc->sc_flags & (SC_OP_WAIT_FOR_BEACON |
-				      SC_OP_WAIT_FOR_CAB |
-				      SC_OP_WAIT_FOR_PSPOLL_DATA |
-				      SC_OP_WAIT_FOR_TX_ACK)))
-			ath9k_hw_setpower(sc->sc_ah,
-					  sc->sc_ah->restore_mode);
+	unsigned long flags;
+
+	spin_lock_irqsave(&sc->sc_pm_lock, flags);
+	if (--sc->ps_usecount != 0)
+		goto unlock;
+
+	if ((sc->hw->conf.flags & IEEE80211_CONF_PS) &&
+		!(sc->sc_flags & (SC_OP_WAIT_FOR_BEACON |
+				SC_OP_WAIT_FOR_CAB |
+				SC_OP_WAIT_FOR_PSPOLL_DATA |
+				SC_OP_WAIT_FOR_TX_ACK)))
+		ath9k_hw_setpower_nolock(sc->sc_ah,
+				      sc->sc_ah->restore_mode);
+
+ unlock:
+	spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
 }
 
 /*