ath9k_hw: disable phy restart on baseband panic caused by RXSM

While receiving unsupported rate frame rx state machine
gets into a state 0xb and if phy_restart happens in that
state, BB would go hang. If RXSM is in 0xb state after
first bb panic, ensure to disable the phy_restart.

Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/ar9003_phy.c b/drivers/net/wireless/ath/ath9k/ar9003_phy.c
index eee23ec..892c48b 100644
--- a/drivers/net/wireless/ath/ath9k/ar9003_phy.c
+++ b/drivers/net/wireless/ath/ath9k/ar9003_phy.c
@@ -1381,3 +1381,25 @@
 		"==== BB update: done ====\n\n");
 }
 EXPORT_SYMBOL(ar9003_hw_bb_watchdog_dbg_info);
+
+void ar9003_hw_disable_phy_restart(struct ath_hw *ah)
+{
+	u32 val;
+
+	/* While receiving unsupported rate frame rx state machine
+	 * gets into a state 0xb and if phy_restart happens in that
+	 * state, BB would go hang. If RXSM is in 0xb state after
+	 * first bb panic, ensure to disable the phy_restart.
+	 */
+	if (!((MS(ah->bb_watchdog_last_status,
+		  AR_PHY_WATCHDOG_RX_OFDM_SM) == 0xb) ||
+	    ah->bb_hang_rx_ofdm))
+		return;
+
+	ah->bb_hang_rx_ofdm = true;
+	val = REG_READ(ah, AR_PHY_RESTART);
+	val &= ~AR_PHY_RESTART_ENA;
+
+	REG_WRITE(ah, AR_PHY_RESTART, val);
+}
+EXPORT_SYMBOL(ar9003_hw_disable_phy_restart);