From eaaedb6ae892d90afcce57655742a79a48249cc3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Josef=20S=C3=B6ntgen?= <josef.soentgen@genode-labs.com>
Date: Fri, 10 Mar 2023 16:53:35 +0100
Subject: [PATCH] wifi: defer supplicant start-up

The SDIO connected wireless device on the PinePhone is not available
on start-up, which leads to the supplicant failing to initalize
'wlan0'. Normally the supplicant would be used in a way that handling
devices that appear at run-time happens gracefully.

Rather than supporting this behavior we defer the start-up of the
supplicant until the device could be openend successfully for now.

Issue #4813
---
 repos/pc/src/lib/wifi/socket_call.cc |  6 ------
 repos/pc/src/lib/wifi/uplink.c       | 29 +++++++++++++++++++++++++++-
 repos/pc/src/lib/wifi/wlan.cc        | 13 ++++++++++++-
 3 files changed, 40 insertions(+), 8 deletions(-)

diff --git a/repos/pc/src/lib/wifi/socket_call.cc b/repos/pc/src/lib/wifi/socket_call.cc
index 97b240dcfd..353027155b 100644
--- a/repos/pc/src/lib/wifi/socket_call.cc
+++ b/repos/pc/src/lib/wifi/socket_call.cc
@@ -474,10 +474,6 @@ class Lx::Socket
 
 static Lx::Socket *_socket;
 
-
-/* implemented in wlan.cc */
-extern Blockade *wpa_blockade;
-
 /* implemented in wlan.cc */
 void _wifi_report_mac_address(Net::Mac_address const &mac_address);
 
@@ -489,8 +485,6 @@ extern "C" int socketcall_task_function(void *)
 
 	void const *mac_addr = nullptr;
 
-	wpa_blockade->wakeup();
-
 	while (true) {
 
 		/*
diff --git a/repos/pc/src/lib/wifi/uplink.c b/repos/pc/src/lib/wifi/uplink.c
index 11434c2b10..f9fd517a3a 100644
--- a/repos/pc/src/lib/wifi/uplink.c
+++ b/repos/pc/src/lib/wifi/uplink.c
@@ -227,6 +227,26 @@ static int uplink_netdev_event(struct notifier_block *this,
 }
 
 
+static int new_device_netdev_event(struct notifier_block *this,
+                                   unsigned long event, void *ptr)
+{
+	if (event == NETDEV_REGISTER)
+		if (uplink_task_struct_ptr)
+			lx_emul_task_unblock(uplink_task_struct_ptr);
+
+	return NOTIFY_DONE;
+}
+
+
+static struct notifier_block new_device_netdev_notifier = {
+    .notifier_call = new_device_netdev_event,
+};
+
+
+/* implemented by wlan.cc */
+extern void wakeup_wpa(void);
+
+
 static int user_task_function(void *arg)
 {
 	struct netdev_event_notification events;
@@ -235,6 +255,12 @@ static int user_task_function(void *arg)
 	events.nb.notifier_call = uplink_netdev_event;
 	events.registered       = false;
 
+	if (register_netdevice_notifier(&new_device_netdev_notifier)) {
+		printk("%s:%d: could not register netdev notifer for "
+		       "new devices, abort\n", __func__, __LINE__);
+		return -1;
+	}
+
 	for (;;) {
 
 		struct net_device *dev;
@@ -246,7 +272,8 @@ static int user_task_function(void *arg)
 				continue;
 
 			/* enable link sensing, repeated calls are handled by testing IFF_UP */
-			dev_open(dev, 0);
+			if (dev_open(dev, 0) == 0)
+				wakeup_wpa();
 
 			/* install rx handler once */
 			if (!netdev_is_rx_handler_busy(dev))
diff --git a/repos/pc/src/lib/wifi/wlan.cc b/repos/pc/src/lib/wifi/wlan.cc
index 04380f9977..5b2e8c47c0 100644
--- a/repos/pc/src/lib/wifi/wlan.cc
+++ b/repos/pc/src/lib/wifi/wlan.cc
@@ -180,7 +180,18 @@ struct Wlan
 };
 
 
-Blockade *wpa_blockade;
+static Blockade *wpa_blockade;
+
+
+extern "C" void wakeup_wpa()
+{
+	static bool called_once = false;
+	if (called_once)
+		return;
+
+	wpa_blockade->wakeup();
+	called_once = true;
+}
 
 
 void wifi_init(Env &env, Blockade &blockade)