From sgruszka@redhat.com Wed Oct 20 10:35:02 2010
From: Stanislaw Gruszka <sgruszka@redhat.com>
To: stable@kernel.org
Subject: [PATCH -stable 2.6.34 2/2] rt2x00: Fix failed SLEEP->AWAKE and AWAKE->SLEEP transitions.
Date: Wed, 20 Oct 2010 16:37:28 +0200

From: Gertjan van Wingerde <gwingerde@gmail.com>

commit 9655a6ec19ca656af246fb80817aa337892aefbf upstream.

Together with "rt2x00: Disable auto wakeup before waking up device"
fix kernel oops/hang reported here:
https://bugzilla.redhat.com/show_bug.cgi?id=642031

(Based on a patch created by Ondrej Zary)

In some circumstances the Ralink devices do not properly go to sleep
or wake up, with timeouts occurring.
Fix this by retrying telling the device that it has to wake up or
sleep.

Signed-off-by: Gertjan van Wingerde <gwingerde@gmail.com>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
---
 drivers/net/wireless/rt2x00/rt2400pci.c |    9 +++++----
 drivers/net/wireless/rt2x00/rt2500pci.c |    9 +++++----
 drivers/net/wireless/rt2x00/rt61pci.c   |    7 ++++---
 drivers/net/wireless/rt2x00/rt73usb.c   |    7 ++++---
 4 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/drivers/net/wireless/rt2x00/rt2400pci.c b/drivers/net/wireless/rt2x00/rt2400pci.c
index 4ba7b038..ad2c98a 100644
--- a/drivers/net/wireless/rt2x00/rt2400pci.c
+++ b/drivers/net/wireless/rt2x00/rt2400pci.c
@@ -926,7 +926,7 @@ static void rt2400pci_disable_radio(struct rt2x00_dev *rt2x00dev)
 static int rt2400pci_set_state(struct rt2x00_dev *rt2x00dev,
 			       enum dev_state state)
 {
-	u32 reg;
+	u32 reg, reg2;
 	unsigned int i;
 	char put_to_sleep;
 	char bbp_state;
@@ -947,11 +947,12 @@ static int rt2400pci_set_state(struct rt2x00_dev *rt2x00dev,
 	 * device has entered the correct state.
 	 */
 	for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
-		rt2x00pci_register_read(rt2x00dev, PWRCSR1, &reg);
-		bbp_state = rt2x00_get_field32(reg, PWRCSR1_BBP_CURR_STATE);
-		rf_state = rt2x00_get_field32(reg, PWRCSR1_RF_CURR_STATE);
+		rt2x00pci_register_read(rt2x00dev, PWRCSR1, &reg2);
+		bbp_state = rt2x00_get_field32(reg2, PWRCSR1_BBP_CURR_STATE);
+		rf_state = rt2x00_get_field32(reg2, PWRCSR1_RF_CURR_STATE);
 		if (bbp_state == state && rf_state == state)
 			return 0;
+		rt2x00pci_register_write(rt2x00dev, PWRCSR1, reg);
 		msleep(10);
 	}
 
diff --git a/drivers/net/wireless/rt2x00/rt2500pci.c b/drivers/net/wireless/rt2x00/rt2500pci.c
index 89d132d..41da3d2 100644
--- a/drivers/net/wireless/rt2x00/rt2500pci.c
+++ b/drivers/net/wireless/rt2x00/rt2500pci.c
@@ -1084,7 +1084,7 @@ static void rt2500pci_disable_radio(struct rt2x00_dev *rt2x00dev)
 static int rt2500pci_set_state(struct rt2x00_dev *rt2x00dev,
 			       enum dev_state state)
 {
-	u32 reg;
+	u32 reg, reg2;
 	unsigned int i;
 	char put_to_sleep;
 	char bbp_state;
@@ -1105,11 +1105,12 @@ static int rt2500pci_set_state(struct rt2x00_dev *rt2x00dev,
 	 * device has entered the correct state.
 	 */
 	for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
-		rt2x00pci_register_read(rt2x00dev, PWRCSR1, &reg);
-		bbp_state = rt2x00_get_field32(reg, PWRCSR1_BBP_CURR_STATE);
-		rf_state = rt2x00_get_field32(reg, PWRCSR1_RF_CURR_STATE);
+		rt2x00pci_register_read(rt2x00dev, PWRCSR1, &reg2);
+		bbp_state = rt2x00_get_field32(reg2, PWRCSR1_BBP_CURR_STATE);
+		rf_state = rt2x00_get_field32(reg2, PWRCSR1_RF_CURR_STATE);
 		if (bbp_state == state && rf_state == state)
 			return 0;
+		rt2x00pci_register_write(rt2x00dev, PWRCSR1, reg);
 		msleep(10);
 	}
 
diff --git a/drivers/net/wireless/rt2x00/rt61pci.c b/drivers/net/wireless/rt2x00/rt61pci.c
index 2e3076f..6a74baf 100644
--- a/drivers/net/wireless/rt2x00/rt61pci.c
+++ b/drivers/net/wireless/rt2x00/rt61pci.c
@@ -1689,7 +1689,7 @@ static void rt61pci_disable_radio(struct rt2x00_dev *rt2x00dev)
 
 static int rt61pci_set_state(struct rt2x00_dev *rt2x00dev, enum dev_state state)
 {
-	u32 reg;
+	u32 reg, reg2;
 	unsigned int i;
 	char put_to_sleep;
 
@@ -1706,10 +1706,11 @@ static int rt61pci_set_state(struct rt2x00_dev *rt2x00dev, enum dev_state state)
 	 * device has entered the correct state.
 	 */
 	for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
-		rt2x00pci_register_read(rt2x00dev, MAC_CSR12, &reg);
-		state = rt2x00_get_field32(reg, MAC_CSR12_BBP_CURRENT_STATE);
+		rt2x00pci_register_read(rt2x00dev, MAC_CSR12, &reg2);
+		state = rt2x00_get_field32(reg2, MAC_CSR12_BBP_CURRENT_STATE);
 		if (state == !put_to_sleep)
 			return 0;
+		rt2x00pci_register_write(rt2x00dev, MAC_CSR12, reg);
 		msleep(10);
 	}
 
diff --git a/drivers/net/wireless/rt2x00/rt73usb.c b/drivers/net/wireless/rt2x00/rt73usb.c
index e35bd19..6e0d82e 100644
--- a/drivers/net/wireless/rt2x00/rt73usb.c
+++ b/drivers/net/wireless/rt2x00/rt73usb.c
@@ -1366,7 +1366,7 @@ static void rt73usb_disable_radio(struct rt2x00_dev *rt2x00dev)
 
 static int rt73usb_set_state(struct rt2x00_dev *rt2x00dev, enum dev_state state)
 {
-	u32 reg;
+	u32 reg, reg2;
 	unsigned int i;
 	char put_to_sleep;
 
@@ -1383,10 +1383,11 @@ static int rt73usb_set_state(struct rt2x00_dev *rt2x00dev, enum dev_state state)
 	 * device has entered the correct state.
 	 */
 	for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
-		rt2x00usb_register_read(rt2x00dev, MAC_CSR12, &reg);
-		state = rt2x00_get_field32(reg, MAC_CSR12_BBP_CURRENT_STATE);
+		rt2x00usb_register_read(rt2x00dev, MAC_CSR12, &reg2);
+		state = rt2x00_get_field32(reg2, MAC_CSR12_BBP_CURRENT_STATE);
 		if (state == !put_to_sleep)
 			return 0;
+		rt2x00usb_register_write(rt2x00dev, MAC_CSR12, reg);
 		msleep(10);
 	}
 
-- 
1.7.2.3