iwlwifi: return commands with error on FW error

When a firmware error occurs, don't just abort synchronous
commands but also return an error (-EIO) and block any new
commands as well. Currently, an error is only returned if
WANT_SKB was set which is confusing and can lead to issues.

Blocking is done until a new firmware image is loaded.
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/iwlwifi/pcie/internal.h

@@ -296,6 +296,7 @@ enum {
 	STATUS_TPOWER_PMI,
 	STATUS_INT_ENABLED,
 	STATUS_RFKILL,
+	STATUS_FW_ERROR,
 };
 
 #define IWL_TRANS_GET_PCIE_TRANS(_iwl_trans) \

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

@@ -582,6 +582,7 @@ static void iwl_irq_handle_error(struct iwl_trans *trans)
 	iwl_dump_csr(trans);
 	iwl_dump_fh(trans, NULL);
 
+	set_bit(STATUS_FW_ERROR, &trans_pcie->status);
 	clear_bit(STATUS_HCMD_ACTIVE, &trans_pcie->status);
 	wake_up(&trans_pcie->wait_command_queue);
 

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

@@ -1026,6 +1026,7 @@ static int iwl_load_given_ucode(struct iwl_trans *trans,
 static int iwl_trans_pcie_start_fw(struct iwl_trans *trans,
 				   const struct fw_img *fw)
 {
+	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 	int ret;
 	bool hw_rfkill;
 
@@ -1035,6 +1036,8 @@ static int iwl_trans_pcie_start_fw(struct iwl_trans *trans,
 		return -EIO;
 	}
 
+	clear_bit(STATUS_FW_ERROR, &trans_pcie->status);
+
 	iwl_enable_rfkill_int(trans);
 
 	/* If platform's RF_KILL switch is NOT set to KILL */

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

@@ -915,6 +915,13 @@ static int iwl_send_cmd_sync(struct iwl_trans *trans, struct iwl_host_cmd *cmd)
 		}
 	}
 
+	if (test_bit(STATUS_FW_ERROR, &trans_pcie->status)) {
+		IWL_ERR(trans, "FW error in SYNC CMD %s\n",
+			trans_pcie_get_cmd_string(trans_pcie, cmd->id));
+		ret = -EIO;
+		goto cancel;
+	}
+
 	if (test_bit(STATUS_RFKILL, &trans_pcie->status)) {
 		IWL_DEBUG_RF_KILL(trans, "RFKILL in SYNC CMD... no rsp\n");
 		ret = -ERFKILL;
@@ -954,6 +961,9 @@ int iwl_trans_pcie_send_cmd(struct iwl_trans *trans, struct iwl_host_cmd *cmd)
 {
 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 
+	if (test_bit(STATUS_FW_ERROR, &trans_pcie->status))
+		return -EIO;
+
 	if (test_bit(STATUS_RFKILL, &trans_pcie->status))
 		return -ERFKILL;