drivers: wifi: nrf7002: Add support for multiple virtual interfaces (VIFs)

Description:
The nRF7002 firmware supports two virtual interfaces (VIFs) that can
operate in different modes (e.g., AP and STA). However, the existing
Zephyr driver only utilizes a single VIF, preventing full
multi-interface support.

This commit extends the nRF7002 driver to support multiple VIFs by
making the following modifications:

* The driver already contains an array of vif_ctx_zep, but only the
first item was being used. Now, a second Ethernet device is registered
using vif_ctx_zep[1], enabling multi-VIF operation.
* Introduced vif_ctx_cnt to keep track of active interfaces and manage
their state effectively.
* Ensured that FMAC (Firmware MAC) is initialized only once, avoiding
redundant initializations when multiple VIFs are present.
* The UMAC control commands previously did not associate responses with
the issuing VIF. A queue is now introduced to track the originating VIF
for each command and correctly route the response event to the
corresponding interface.

Signed-off-by: Hanan Arshad <hananarshad619@gmail.com>

Author: hanan619

drivers/wifi/nrf_wifi/Kconfig.nrfwifi

@@ -108,6 +108,15 @@ config NRF70_AP_MODE
 	depends on WIFI_NM_WPA_SUPPLICANT_AP
 	default y if WIFI_USAGE_MODE_AP || WIFI_USAGE_MODE_STA_AP
 
+config NRF70_ENABLE_DUAL_VIF
+	bool "Dual virtual Wi-Fi interfaces"
+	default y if WIFI_NM_MAX_MANAGED_INTERFACES = 2
+	depends on (WIFI_NRF7002 || WIFI_NRF7001) && NET_L2_ETHERNET
+	help
+	  Enable support for two virtual Wi-Fi interfaces (VIFs).
+	  When enabled, the driver can operate two VIFs simultaneously,
+	  allowing use cases such as one interface in AP mode and another in STA mode.
+
 config NRF70_P2P_MODE
 	bool "P2P support in driver"
 

drivers/wifi/nrf_wifi/src/fmac_main.c

@@ -725,7 +725,19 @@ static int nrf_wifi_drv_main_zep(const struct device *dev)
 	struct nrf_wifi_data_config_params data_config = { 0 };
 	struct rx_buf_pool_params rx_buf_pools[MAX_NUM_OF_RX_QUEUES];
 	struct nrf_wifi_vif_ctx_zep *vif_ctx_zep = dev->data;
+	static unsigned int vif_ctx_cnt;
 
+	if (vif_ctx_cnt >= MAX_NUM_VIFS) {
+		LOG_ERR("%s: Max number of VIFs reached", __func__);
+		return -ENOMEM;
+	}
+
+	if (vif_ctx_cnt >= 1) {
+		/* FMAC is already initialized for VIF-0 */
+		return 0;
+	}
+
+	++vif_ctx_cnt;
 	vif_ctx_zep->rpu_ctx_zep = &rpu_drv_priv_zep.rpu_ctx_zep;
 
 #ifdef CONFIG_NRF70_DATA_TX
@@ -953,6 +965,21 @@ ETH_NET_DEVICE_DT_INST_DEFINE(0,
 		    CONFIG_WIFI_INIT_PRIORITY, /* prio */
 		    &wifi_offload_ops, /* api */
 		    CONFIG_NRF_WIFI_IFACE_MTU); /*mtu */
+#ifdef CONFIG_NRF70_ENABLE_DUAL_VIF
+/* Register second interface */
+ETH_NET_DEVICE_DT_INST_DEFINE(1,
+		    nrf_wifi_drv_main_zep, /* init_fn */
+		    NULL, /* pm_action_cb */
+		    &rpu_drv_priv_zep.rpu_ctx_zep.vif_ctx_zep[1], /* data */
+#ifdef CONFIG_NRF70_STA_MODE
+		    &wpa_supp_ops, /* cfg */
+#else /* CONFIG_NRF70_STA_MODE */
+		    NULL, /* cfg */
+#endif /* !CONFIG_NRF70_STA_MODE */
+		    CONFIG_WIFI_INIT_PRIORITY, /* prio */
+		    &wifi_offload_ops, /* api */
+		    CONFIG_NRF_WIFI_IFACE_MTU); /*mtu */
+#endif /* NRF70_ENABLE_DUAL_VIF */
 #else
 DEVICE_DT_INST_DEFINE(0,
 	      nrf_wifi_drv_main_zep, /* init_fn */

drivers/wifi/nrf_wifi/src/net_if.c

@@ -794,8 +794,7 @@ int nrf_wifi_if_start_zep(const struct device *dev)
 	}
 
 	k_mutex_init(&vif_ctx_zep->vif_lock);
-	rpu_ctx_zep->vif_ctx_zep[vif_ctx_zep->vif_idx].if_type =
-		add_vif_info.iftype;
+	vif_ctx_zep->if_type = add_vif_info.iftype;
 
 	/* Check if user has provided a valid MAC address, if not
 	 * fetch it from OTP.

drivers/wifi/nrf_wifi/src/wpa_supp_if.c

@@ -447,7 +447,10 @@ void *nrf_wifi_wpa_supp_dev_init(void *supp_drv_if_ctx, const char *iface_name,
 				 struct zep_wpa_supp_dev_callbk_fns *supp_callbk_fns)
 {
 	struct nrf_wifi_vif_ctx_zep *vif_ctx_zep = NULL;
-	const struct device *device = DEVICE_DT_GET(DT_CHOSEN(zephyr_wifi));
+	/* Get device for each interface */
+	int if_idx = net_if_get_by_name(iface_name);
+	struct net_if *iface = net_if_get_by_index(if_idx);
+	const struct device *device = net_if_get_device(iface);
 
 	if (!device) {
 		LOG_ERR("%s: Interface %s not found", __func__, iface_name);