From a34d0a0da1abae46a5f6ebd06fb0ec484ca099d9 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Thu, 2 Feb 2017 10:14:51 +0100 Subject: [PATCH] ath9k_hw: check if the chip failed to wake up In an RFC patch, Sven Eckelmann and Simon Wunderlich reported: "QCA 802.11n chips (especially AR9330/AR9340) sometimes end up in a state in which a read of AR_CFG always returns 0xdeadbeef. This should not happen when when the power_mode of the device is ATH9K_PM_AWAKE." Include the check for the default register state in the existing MAC hang check. Signed-off-by: Felix Fietkau Signed-off-by: Kalle Valo --- drivers/net/wireless/ath/ath9k/hw.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c index ac36873d6da4..8c5c2dd8fa7f 100644 --- a/drivers/net/wireless/ath/ath9k/hw.c +++ b/drivers/net/wireless/ath/ath9k/hw.c @@ -1603,6 +1603,10 @@ bool ath9k_hw_check_alive(struct ath_hw *ah) int count = 50; u32 reg, last_val; + /* Check if chip failed to wake up */ + if (REG_READ(ah, AR_CFG) == 0xdeadbeef) + return false; + if (AR_SREV_9300(ah)) return !ath9k_hw_detect_mac_hang(ah); -- 2.20.1