drivers: wifi: esp: fix hostname configuration

By the time hostname configuration was implemented, driver was switching
only between STA and STA+AP modes. After dynamic selection between NONE,
STA, AP and STA+AP was implemented (commit referenced below), hostname
configuration no longer takes effect when ESP chip obtains address over
DHCP (and sends hostname in the DHCP request).

Set hostname each time after enabling STA mode, so that it takes effect
in DHCP requests.

Fixes: 03ce610 ("drivers: wifi: esp: control CWMODE depending on
  current needs")
Signed-off-by: Marcin Niestroj <[email protected]>

Author: mniestroj

drivers/wifi/esp/esp.c

@@ -67,6 +67,20 @@ K_KERNEL_STACK_DEFINE(esp_workq_stack,
 
 struct esp_data esp_driver_data;
 
+static void esp_configure_hostname(struct esp_data *data)
+{
+#if defined(CONFIG_NET_HOSTNAME_ENABLE)
+	char cmd[sizeof("AT+CWHOSTNAME=\"\"") + NET_HOSTNAME_MAX_LEN];
+
+	snprintk(cmd, sizeof(cmd), "AT+CWHOSTNAME=\"%s\"", net_hostname_get());
+	cmd[sizeof(cmd) - 1] = '\0';
+
+	esp_cmd_send(data, NULL, 0, cmd, ESP_CMD_TIMEOUT);
+#else
+	ARG_UNUSED(data);
+#endif
+}
+
 static inline uint8_t esp_mode_from_flags(struct esp_data *data)
 {
 	uint8_t flags = data->flags;
@@ -111,10 +125,25 @@ static int esp_mode_switch(struct esp_data *data, uint8_t mode)
 static int esp_mode_switch_if_needed(struct esp_data *data)
 {
 	uint8_t new_mode = esp_mode_from_flags(data);
+	uint8_t old_mode = data->mode;
+	int err;
+
+	if (old_mode == new_mode) {
+		return 0;
+	}
+
+	data->mode = new_mode;
 
-	if (data->mode != new_mode) {
-		data->mode = new_mode;
-		return esp_mode_switch(data, new_mode);
+	err = esp_mode_switch(data, new_mode);
+	if (err) {
+		return err;
+	}
+
+	if (!(old_mode & ESP_MODE_STA) && (new_mode & ESP_MODE_STA)) {
+		/*
+		 * Hostname change is applied only when STA is enabled.
+		 */
+		esp_configure_hostname(data);
 	}
 
 	return 0;
@@ -877,20 +906,6 @@ static int esp_mgmt_ap_disable(const struct device *dev)
 	return esp_mode_flags_clear(data, EDF_AP_ENABLED);
 }
 
-static void esp_configure_hostname(struct esp_data *data)
-{
-#if defined(CONFIG_NET_HOSTNAME_ENABLE)
-	char cmd[sizeof("AT+CWHOSTNAME=\"\"") + NET_HOSTNAME_MAX_LEN];
-
-	snprintk(cmd, sizeof(cmd), "AT+CWHOSTNAME=\"%s\"", net_hostname_get());
-	cmd[sizeof(cmd) - 1] = '\0';
-
-	esp_cmd_send(data, NULL, 0, cmd, ESP_CMD_TIMEOUT);
-#else
-	ARG_UNUSED(data);
-#endif
-}
-
 static void esp_init_work(struct k_work *work)
 {
 	struct esp_data *dev;
@@ -981,7 +996,16 @@ static void esp_init_work(struct k_work *work)
 	net_if_set_link_addr(dev->net_iface, dev->mac_addr,
 			     sizeof(dev->mac_addr), NET_LINK_ETHERNET);
 
-	esp_configure_hostname(dev);
+	if (IS_ENABLED(CONFIG_WIFI_ESP_AT_VERSION_1_7)) {
+		/* This is the mode entered in above setup commands */
+		dev->mode = ESP_MODE_STA;
+
+		/*
+		 * In case of ESP 1.7 this is the first time CWMODE is entered
+		 * STA mode, so request hostname change now.
+		 */
+		esp_configure_hostname(dev);
+	}
 
 	LOG_INF("ESP Wi-Fi ready");