wifi: iwlwifi: pcie: don't allow hw-rfkill to stop device on gen2

On new devices the HW rfkill shutdown doesn't need to be handled
"as fast as possible", so disallow the immediate shutdown mode
here via documentation and a warning.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240204235836.794c5387e67e.I064365428815ec3135afa345fbbde78449b60203@changeidSigned-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/intel/iwlwifi/iwl-op-mode.h

@@ -68,9 +68,11 @@ struct iwl_cfg;
  *	Must be atomic and called with BH disabled.
  * @queue_not_full: notifies that a HW queue is not full any more.
  *	Must be atomic and called with BH disabled.
- * @hw_rf_kill:notifies of a change in the HW rf kill switch. True means that
+ * @hw_rf_kill: notifies of a change in the HW rf kill switch. True means that
  *	the radio is killed. Return %true if the device should be stopped by
  *	the transport immediately after the call. May sleep.
+ *	Note that this must not return %true for newer devices using gen2 PCIe
+ *	transport.
  * @free_skb: allows the transport layer to free skbs that haven't been
  *	reclaimed by the op_mode. This can happen when the driver is freed and
  *	there are Tx packets pending in the transport layer.

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

@@ -1484,12 +1484,9 @@ void iwl_trans_pcie_rf_kill(struct iwl_trans *trans, bool state, bool from_irq)
 
 	IWL_WARN(trans, "reporting RF_KILL (radio %s)\n",
 		 state ? "disabled" : "enabled");
-	if (iwl_op_mode_hw_rf_kill(trans->op_mode, state)) {
-		if (trans->trans_cfg->gen2)
-			_iwl_trans_pcie_gen2_stop_device(trans);
-		else
-			_iwl_trans_pcie_stop_device(trans, from_irq);
-	}
+	if (iwl_op_mode_hw_rf_kill(trans->op_mode, state) &&
+	    !WARN_ON(trans->trans_cfg->gen2))
+		_iwl_trans_pcie_stop_device(trans, from_irq);
 }
 
 void iwl_pcie_d3_complete_suspend(struct iwl_trans *trans,