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>

diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c
index e340dac..71f27f3 100644 (file)
--- 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,