wifi: add RFKILL notification interface

Add somewhat cosmetic changes to the RFKILL interface used between
the management layer and the driver library to make the intent clear.

Issue #4861.

repos/dde_linux/include/wifi/rfkill.h

@@ -14,12 +14,34 @@
 #ifndef _WIFI__RFKILL_H_
 #define _WIFI__RFKILL_H_
 
+#include <util/interface.h>
 
 namespace Wifi {
 
+	/*
+	 * FD used to poll RFKILL state from the supplicant.
+	 */
 	enum { RFKILL_FD = 42, };
-}
 
-bool wifi_get_rfkill(void);
+	struct Rfkill_notification_handler : Genode::Interface
+	{
+		virtual void rfkill_notify() = 0;
+	};
+
+	void rfkill_establish_handler(Rfkill_notification_handler &);
+
+	/**
+	 * Query current RFKILL state
+	 */
+	bool rfkill_blocked();
+
+	/**
+	 * Set RFKILL state from the frontend
+	 *
+	 * May be only called from an EP context.
+	 */
+	void set_rfkill(bool);
+
+} /* namespace Wifi */
 
 #endif /* _WIFI__RFKILL_H_ */

repos/dde_linux/lib/symbols/wifi

@@ -21,3 +21,6 @@ wifi_ifindex T
 wifi_ifname T
 _ZN4Wifi20firmware_get_requestEv T
 _ZN4Wifi26firmware_establish_handlerERNS_24Firmware_request_handlerE T
+_ZN4Wifi10set_rfkillEb T
+_ZN4Wifi14rfkill_blockedEv T
+_ZN4Wifi24rfkill_establish_handlerERNS_27Rfkill_notification_handlerE T

repos/dde_linux/src/drivers/wifi/frontend.h

@@ -62,9 +62,6 @@
 /* declare manually as it is a internal hack^Winterface */
 extern void wifi_kick_socketcall();
 
-extern bool _wifi_get_rfkill(void);
-extern bool _wifi_set_rfkill(bool);
-
 
 namespace Wifi {
 	struct Frontend;
@@ -252,7 +249,7 @@ static void for_each_result_line(char const *msg, FUNC const &func)
 /*
  * Wifi driver front end
  */
-struct Wifi::Frontend
+struct Wifi::Frontend : Wifi::Rfkill_notification_handler
 {
 	Frontend(const Frontend&) = delete;
 	Frontend& operator=(const Frontend&) = delete;
@@ -346,7 +343,7 @@ struct Wifi::Frontend
 
 	void _handle_rfkill()
 	{
-		_rfkilled = _wifi_get_rfkill();
+		_rfkilled = Wifi::rfkill_blocked();
 
 		/* re-enable scan timer */
 		if (!_rfkilled) {
@@ -410,7 +407,7 @@ struct Wifi::Frontend
 		 */
 		if (config.has_attribute("rfkill")) {
 			bool const blocked = config.attribute_value("rfkill", false);
-			_wifi_set_rfkill(blocked);
+			Wifi::set_rfkill(blocked);
 
 			/*
 			 * In case we get blocked set rfkilled immediately to prevent
@@ -1589,13 +1586,13 @@ struct Wifi::Frontend
 	}
 
 	/**
-	 * Get RFKILL signal capability
+	 * Trigger RFKILL notification
 	 *
 	 * Used by the wifi_drv to notify front end.
 	 */
-	Genode::Signal_context_capability rfkill_sigh()
+	void rfkill_notify() override
 	{
-		return _rfkill_handler;
+		_rfkill_handler.local_submit();
 	}
 
 	/**

repos/dde_linux/src/drivers/wifi/main.cc

@@ -169,8 +169,8 @@ struct Main
 	{
 		_frontend.construct(env, _wifi_msg_buffer);
 		_wifi_frontend = &*_frontend;
-		wifi_set_rfkill_sigh(_wifi_frontend->rfkill_sigh());
 
+		Wifi::rfkill_establish_handler(*_wifi_frontend);
 		Wifi::firmware_establish_handler(_request_handler);
 
 		_wpa.construct(env, _wpa_startup_blockade);

repos/dde_linux/src/lib/wifi/symbol.map

@@ -11,7 +11,7 @@
 		/* Wifi::Socket_call instance */
 		socket_call;
 		/* rfkill interface */
-		_*wifi_*_rfkill*;
+		_*Wifi*rfkill*;
 		_*wifi_kick_*;
 
 		_*Wifi*firmware*;

repos/dde_linux/src/lib/wifi/wlan.cc

@@ -29,6 +29,7 @@
 
 /* wifi includes */
 #include <wifi/firmware.h>
+#include <wifi/rfkill.h>
 
 /* local includes */
 #include "lx_user.h"
@@ -36,12 +37,11 @@
 
 using namespace Genode;
 
+/* RFKILL handling */
 
 extern "C" int  lx_emul_rfkill_get_any(void);
 extern "C" void lx_emul_rfkill_switch_all(int blocked);
 
-static Signal_context_capability _rfkill_sigh_cap;
-
 
 bool _wifi_get_rfkill(void)
 {
@@ -53,7 +53,25 @@ bool _wifi_get_rfkill(void)
 }
 
 
-void _wifi_set_rfkill(bool blocked)
+struct Rfkill_helper
+{
+	Wifi::Rfkill_notification_handler &_handler;
+
+	Rfkill_helper(Wifi::Rfkill_notification_handler &handler)
+	:
+		_handler { handler }
+	{ }
+
+	void submit_notification()
+	{
+		_handler.rfkill_notify();
+	}
+};
+
+Constructible<Rfkill_helper> rfkill_helper { };
+
+
+void Wifi::set_rfkill(bool blocked)
 {
 	if (!rfkill_task_struct_ptr)
 		return;
@@ -72,11 +90,12 @@ void _wifi_set_rfkill(bool blocked)
 	lx_emul_task_unblock(uplink_task_struct_ptr);
 	Lx_kit::env().scheduler.schedule();
 
-	Signal_transmitter(_rfkill_sigh_cap).submit();
+	if (rfkill_helper.constructed())
+		rfkill_helper->submit_notification();
 }
 
 
-bool wifi_get_rfkill(void)
+bool Wifi::rfkill_blocked(void)
 {
 	return _wifi_get_rfkill();
 }
@@ -370,9 +389,9 @@ void wifi_init(Env &env, Blockade &blockade)
 }
 
 
-void wifi_set_rfkill_sigh(Signal_context_capability cap)
+void Wifi::rfkill_establish_handler(Wifi::Rfkill_notification_handler &handler)
 {
-	_rfkill_sigh_cap = cap;
+	rfkill_helper.construct(handler);
 }
 
 

repos/dde_linux/src/lib/wpa_driver_nl80211/rfkill_genode.cc

@@ -44,7 +44,7 @@ struct rfkill_data {
 static void rfkill_receive(int sock, void *eloop_ctx, void *sock_ctx)
 {
 	struct rfkill_data * const rfkill = (rfkill_data*)eloop_ctx;
-	bool const new_blocked = wifi_get_rfkill();
+	bool const new_blocked = Wifi::rfkill_blocked();
 
 	if (new_blocked != rfkill->blocked) {
 		rfkill->blocked = new_blocked;