iwlwifi: pcie: clear RFKILL interrupt in AMPG

If we forget to do so, we can't send HCMD to firmware while
the NIC is in RFKILL state.

Cc: stable@vger.kernel.org
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/iwlwifi/iwl-prph.h

@@ -97,6 +97,8 @@
 
 #define APMG_PCIDEV_STT_VAL_L1_ACT_DIS		(0x00000800)
 
+#define APMG_RTC_INT_STT_RFKILL		(0x10000000)
+
 /* Device system time */
 #define DEVICE_SYSTEM_TIME_REG 0xA0206C
 

drivers/net/wireless/iwlwifi/pcie/rx.c

@@ -888,6 +888,14 @@ irqreturn_t iwl_pcie_irq_handler(int irq, void *dev_id)
 
 		iwl_op_mode_hw_rf_kill(trans->op_mode, hw_rfkill);
 		if (hw_rfkill) {
+			/*
+			 * Clear the interrupt in APMG if the NIC is going down.
+			 * Note that when the NIC exits RFkill (else branch), we
+			 * can't access prph and the NIC will be reset in
+			 * start_hw anyway.
+			 */
+			iwl_write_prph(trans, APMG_RTC_INT_STT_REG,
+				       APMG_RTC_INT_STT_RFKILL);
 			set_bit(STATUS_RFKILL, &trans_pcie->status);
 			if (test_and_clear_bit(STATUS_HCMD_ACTIVE,
 					       &trans_pcie->status))