Implement WiFi networking

README.md

@@ -6,7 +6,7 @@ Networked bedside clock utilising an ESP32-SOLO-1.
 
 - [ ] Audio alarms
 - [x] 7 segment display
-- [ ] WiFi networking
+- [x] WiFi networking
 - [x] Console for configuration
 - [ ] TCP API for configuration
 - [ ] SNTP synchronisation

components/wifi/CMakeLists.txt

@@ -0,0 +1,5 @@
+idf_component_register(
+  SRCS "wifi.c"
+  INCLUDE_DIRS "."
+  REQUIRES esp_event esp_system esp_wifi settings
+)

components/wifi/wifi.c

@@ -0,0 +1,246 @@
+/*
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Copyright (c) Camden Dixie O'Brien
+ */
+
+#include "wifi.h"
+
+#include "console.h"
+#include "settings.h"
+
+#include "esp_event.h"
+#include "esp_log.h"
+#include "esp_system.h"
+#include "esp_wifi.h"
+#include "freertos/event_groups.h"
+#include <string.h>
+
+#define TAG "Wifi"
+
+static wifi_config_t config;
+static WifiStatus status;
+static unsigned retries;
+static esp_netif_ip_info_t ip_info;
+static esp_netif_t *net_if;
+
+static void wifi_event_handler(
+    void *arg, esp_event_base_t event_base, int32_t event_id,
+    void *event_data)
+{
+	(void)arg;
+	(void)event_base;
+
+	esp_err_t error;
+
+	switch (event_id) {
+	case WIFI_EVENT_STA_START:
+		error = esp_wifi_connect();
+		if (error != ESP_OK)
+			ESP_LOGE(TAG, "Error connecting to WiFi: %04x", error);
+		break;
+
+	case WIFI_EVENT_STA_DISCONNECTED:
+		if (retries < CONFIG_WIFI_MAX_RETRIES) {
+			ESP_LOGI(TAG, "Retrying connection");
+			error = esp_wifi_connect();
+			if (error != ESP_OK)
+				ESP_LOGE(TAG, "Error connecting to WiFi: %04x", error);
+			++retries;
+		} else {
+			ESP_LOGW(
+			    TAG, "Failed to connect to network %s", config.sta.ssid);
+		}
+		break;
+
+	default:
+		ESP_LOGI(TAG, "Unhandled WiFi event: %ld", event_id);
+		break;
+	}
+}
+
+static void got_ip_event_handler(
+    void *arg, esp_event_base_t event_base, int32_t event_id,
+    void *event_data)
+{
+	(void)arg;
+	(void)event_base;
+
+	if (event_id != IP_EVENT_STA_GOT_IP) {
+		ESP_LOGW(TAG, "Unexpected IP event received: %ld", event_id);
+		return;
+	}
+
+	ip_event_got_ip_t *got_ip_data = (ip_event_got_ip_t *)event_data;
+	memcpy(&ip_info, &got_ip_data->ip_info, sizeof(ip_info));
+
+	ESP_LOGI(TAG, "Got IP " IPSTR, IP2STR(&ip_info.ip));
+	status = WIFI_STATUS_CONNECTED;
+}
+
+static void handle_hostname_update(const char *hostname)
+{
+	const esp_err_t error = esp_netif_set_hostname(net_if, hostname);
+	if (error != ESP_OK)
+		ESP_LOGE(TAG, "Failed to set hostname: %04x", error);
+
+	wifi_reconnect();
+}
+
+static void handle_ssid_update(const char *ssid)
+{
+	ESP_LOGI(TAG, "SSID updated");
+
+	if (strlen(ssid) > sizeof(config.sta.ssid) - 1)
+		ESP_LOGW(TAG, "SSID too long (truncated)");
+	strncpy((char *)config.sta.ssid, ssid, sizeof(config.sta.ssid));
+	config.sta.ssid[sizeof(config.sta.ssid) - 1] = '\0';
+
+	const esp_err_t error = esp_wifi_set_config(WIFI_IF_STA, &config);
+	if (error != ESP_OK) {
+		ESP_LOGE(TAG, "Error setting config: %04x", error);
+		return;
+	}
+
+	wifi_reconnect();
+}
+
+static void handle_psk_update(const char *psk)
+{
+	ESP_LOGI(TAG, "PSK updated");
+
+	if (strlen(psk) > sizeof(config.sta.password) - 1)
+		ESP_LOGW(TAG, "PSK too long (truncated)");
+	strncpy((char *)config.sta.password, psk, sizeof(config.sta.password));
+	config.sta.password[sizeof(config.sta.password) - 1] = '\0';
+
+	const esp_err_t error = esp_wifi_set_config(WIFI_IF_STA, &config);
+	if (error != ESP_OK) {
+		ESP_LOGE(TAG, "Error setting config: %04x", error);
+		return;
+	}
+
+	wifi_reconnect();
+}
+
+static int command_func(int argc, char **argv)
+{
+	if (argc != 2) {
+		printf("Invalid number of arguments\n");
+		return 1;
+	} else if (strcmp(argv[1], "status") == 0) {
+		printf(
+		    "%s\n",
+		    status == WIFI_STATUS_CONNECTED ? "Connected" : "Disconnected");
+		return 0;
+	} else if (strcmp(argv[1], "reconnect") == 0) {
+		wifi_reconnect();
+		return 0;
+	} else if (strcmp(argv[1], "ip") == 0) {
+		printf(IPSTR "\n", IP2STR(&ip_info.ip));
+		return 0;
+	} else {
+		printf("Subcommand not recognised\n");
+		return 1;
+	}
+}
+
+void wifi_init(void)
+{
+	esp_err_t error;
+
+	status = WIFI_STATUS_DISCONNECTED;
+
+	error = esp_netif_init();
+	if (error != ESP_OK) {
+		ESP_LOGE(TAG, "Error initializing network stack: %04x", error);
+		return;
+	}
+
+	error = esp_event_loop_create_default();
+	if (error != ESP_OK) {
+		ESP_LOGE(TAG, "Error creating event loop: %04x", error);
+		return;
+	}
+	net_if = esp_netif_create_default_wifi_sta();
+
+	wifi_init_config_t init_config = WIFI_INIT_CONFIG_DEFAULT();
+	error = esp_wifi_init(&init_config);
+	if (error != ESP_OK) {
+		ESP_LOGE(TAG, "Error initializing WiFi stack: %04x", error);
+		return;
+	}
+
+	esp_event_handler_instance_t instance;
+	error = esp_event_handler_instance_register(
+	    WIFI_EVENT, ESP_EVENT_ANY_ID, &wifi_event_handler, NULL, &instance);
+	if (error != ESP_OK) {
+		ESP_LOGE(TAG, "Error registering WiFi event handler: %04x", error);
+		return;
+	}
+	error = esp_event_handler_instance_register(
+	    IP_EVENT, IP_EVENT_STA_GOT_IP, &got_ip_event_handler, NULL,
+	    &instance);
+	if (error != ESP_OK) {
+		ESP_LOGE(TAG, "Error registering IP event handler: %04x", error);
+		return;
+	}
+
+	error = esp_wifi_set_mode(WIFI_MODE_STA);
+	if (error != ESP_OK) {
+		ESP_LOGE(TAG, "Error setting mode: %04x", error);
+		return;
+	}
+
+	char hostname[SETTINGS_MAX_VALUE_SIZE];
+	(void)settings_get_hostname(hostname, SETTINGS_MAX_VALUE_SIZE);
+	error = esp_netif_set_hostname(net_if, hostname);
+	if (error != ESP_OK)
+		ESP_LOGE(TAG, "Failed to set hostname: %04x", error);
+
+	memset(&config, 0, sizeof(config));
+	if (settings_get_ssid((char *)config.sta.ssid, sizeof(config.sta.ssid))
+	    > sizeof(config.sta.ssid))
+		ESP_LOGW(TAG, "SSID too long (truncated)");
+	if (settings_get_psk(
+	        (char *)config.sta.password, sizeof(config.sta.password))
+	    > sizeof(config.sta.password))
+		ESP_LOGW(TAG, "PSK too long (truncated)");
+	error = esp_wifi_set_config(WIFI_IF_STA, &config);
+	if (error != ESP_OK) {
+		ESP_LOGE(TAG, "Error setting config: %04x", error);
+		return;
+	}
+
+	error = esp_wifi_start();
+	if (error != ESP_OK) {
+		ESP_LOGE(TAG, "Error starting WiFi: %04x", error);
+		return;
+	}
+
+	settings_add_hostname_callback(&handle_hostname_update);
+	settings_add_ssid_callback(&handle_ssid_update);
+	settings_add_psk_callback(&handle_psk_update);
+
+	console_register(
+	    "wifi", "Manage WiFi connection", "wifi <status|reconnect|ip>",
+	    command_func);
+}
+
+void wifi_reconnect(void)
+{
+	esp_err_t error;
+
+	error = esp_wifi_disconnect();
+	if (error != ESP_OK)
+		ESP_LOGE(TAG, "Error disconnecting from WiFi: %04x", error);
+	error = esp_wifi_connect();
+	if (error != ESP_OK)
+		ESP_LOGE(TAG, "Error connecting to WiFi: %04x", error);
+
+	retries = 0;
+}
+
+WifiStatus get_wifi_status(void)
+{
+	return status;
+}

components/wifi/wifi.h

@@ -0,0 +1,29 @@
+/*
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Copyright (c) Camden Dixie O'Brien
+ */
+
+#ifndef WIFI_H
+#define WIFI_H
+
+typedef enum {
+	WIFI_STATUS_DISCONNECTED,
+	WIFI_STATUS_CONNECTED,
+} WifiStatus;
+
+/**
+ * Initialize the WiFi subsystem, and try to connect to the network.
+ */
+void wifi_init(void);
+
+/**
+ * Disconnect and reconnect to WiFi.
+ */
+void wifi_reconnect(void);
+
+/**
+ * Get the status of the WiFi connection.
+ */
+WifiStatus get_wifi_status(void);
+
+#endif

main/CMakeLists.txt

@@ -1,5 +1,5 @@
 idf_component_register(
   SRCS "main.c"
   INCLUDE_DIRS "."
-  REQUIRES console_wrapper display settings
+  REQUIRES console_wrapper display settings wifi
 )

main/Kconfig.projbuild

@@ -11,4 +11,7 @@ menu "Bedside clock settings"
      config DEFAULT_TIMEZONE
             string "Default timezone"
             default "Europe/London"
+     config WIFI_MAX_RETRIES
+            int "Maximum number of times to retry connecting to WiFi network"
+            default 10
 endmenu

main/main.c

@@ -6,10 +6,12 @@
 #include "console.h"
 #include "display.h"
 #include "settings.h"
+#include "wifi.h"
 
 void app_main(void)
 {
 	console_init();
 	settings_init();
 	display_init();
+	wifi_init();
 }