ath9k: Do an AHB reset before doing RTC reset

Doing an RTC reset when DMA is active may corrupt memory,
make sure no DMA is active at this moment by doing an
AHB reset.

Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c
index e340dacc6ebe..71f27f324cea 100644
--- a/drivers/net/wireless/ath/ath9k/hw.c
+++ b/drivers/net/wireless/ath/ath9k/hw.c
@@ -1712,8 +1712,15 @@ static bool ath9k_hw_set_reset_power_on(struct ath_hw *ah)
         REG_WRITE(ah, AR_RTC_FORCE_WAKE, AR_RTC_FORCE_WAKE_EN |
                   AR_RTC_FORCE_WAKE_ON_INT);
 
+        if (!AR_SREV_9100(ah))
+                REG_WRITE(ah, AR_RC, AR_RC_AHB);
+
         REG_WRITE(ah, AR_RTC_RESET, 0);
         udelay(2);
+
+        if (!AR_SREV_9100(ah))
+                REG_WRITE(ah, AR_RC, 0);
+
         REG_WRITE(ah, AR_RTC_RESET, 1);
 
         if (!ath9k_hw_wait(ah,