From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Felix Fietkau , Kalle Valo , Amit Pundir Subject: [PATCH 4.4 07/50] ath9k_hw: check if the chip failed to wake up Date: Fri, 27 Apr 2018 15:58:09 +0200 Message-Id: <20180427135656.069466594@linuxfoundation.org> In-Reply-To: <20180427135655.623669681@linuxfoundation.org> References: <20180427135655.623669681@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Felix Fietkau commit a34d0a0da1abae46a5f6ebd06fb0ec484ca099d9 upstream. 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 Cc: Amit Pundir Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/ath/ath9k/hw.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/net/wireless/ath/ath9k/hw.c +++ b/drivers/net/wireless/ath/ath9k/hw.c @@ -1595,6 +1595,10 @@ bool ath9k_hw_check_alive(struct ath_hw 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);