driver: wifi: siwx91x: Add roaming configuration

- Defined Kconfig macros for Roam config
- Added set roam configuration API call
  after BGSCAN

Signed-off-by: Nitin Pandey <[email protected]>

Author: nipandey-01

drivers/wifi/siwx91x/Kconfig.siwx91x

@@ -45,6 +45,44 @@ config NET_MGMT_EVENT_STACK_SIZE
 config NET_MGMT_EVENT_QUEUE_SIZE
 	default 10
 
+config WIFI_SILABS_SIWX91X_ENABLE_ROAMING
+	bool "WiFi roaming support"
+	help
+	  Enable this option to configure roaming parameters.
+	  Roaming will be enabled automatically when the
+	  background scan is active, improving connectivity
+	  and performance during transitions between access points.
+
+config WIFI_SILABS_SIWX91X_ROAMING_USE_DEAUTH
+	bool "Use deauth frames for roaming"
+	depends on WIFI_SILABS_SIWX91X_ENABLE_ROAMING
+	help
+	  Enable this option to allow roaming using
+	  deauthentication frames. By default, roaming
+	  is performed using Null data packets.
+
+config WIFI_SILABS_SIWX91X_ROAMING_TRIGGER_LEVEL
+	int "Default value of roam trigger level (in dBm)"
+	default -70
+	range -10 -100
+	depends on WIFI_SILABS_SIWX91X_ENABLE_ROAMING
+	help
+	  Sets the default roam trigger level. Higher values trigger
+	  earlier roaming; lower values delay it. It determines
+	  when to start searching for a new AP.
+
+config WIFI_SILABS_SIWX91X_ROAMING_TRIGGER_LEVEL_CHANGE
+	int "Default value of roam trigger level change (in dBm)"
+	default 5
+	range 0 90
+	depends on WIFI_SILABS_SIWX91X_ENABLE_ROAMING
+	help
+	  Configure the default trigger level change for WiFi roaming.
+	  This value determines the change in signal strength (in dBm)
+	  required to initiate a roaming event. A smaller value may result
+	  in more sensitive roaming behavior, while a larger value can
+	  reduce the frequency of roaming events. It determines
+	  the signal difference needed to switch to a new AP.
 
 config WIFI_SILABS_SIWX91X_ADV_SCAN_THRESHOLD
 	int "Advanced scan threshold (in dBm)"

drivers/wifi/siwx91x/siwx91x_wifi.c

@@ -20,6 +20,7 @@
 #include "sl_net_default_values.h"
 #include "sl_wifi.h"
 #include "sl_net.h"
+#include "sl_wifi_constants.h"
 
 #define SIWX91X_DRIVER_VERSION KERNEL_VERSION_STRING
 
@@ -537,6 +538,15 @@ static int siwx91x_scan(const struct device *dev, struct wifi_scan_params *z_sca
 		.enable_multi_probe = CONFIG_WIFI_SILABS_SIWX91X_ADV_MULTIPROBE,
 		.enable_instant_scan = CONFIG_WIFI_SILABS_SIWX91X_ENABLE_INSTANT_SCAN,
 	};
+	sl_wifi_roam_configuration_t roam_configuration = {
+#ifdef CONFIG_WIFI_SILABS_SIWX91X_ENABLE_ROAMING
+		.trigger_level = CONFIG_WIFI_SILABS_SIWX91X_ROAMING_TRIGGER_LEVEL,
+		.trigger_level_change = CONFIG_WIFI_SILABS_SIWX91X_ROAMING_TRIGGER_LEVEL_CHANGE,
+#else
+		.trigger_level = SL_WIFI_NEVER_ROAM,
+		.trigger_level_change = 0,
+#endif
+	};
 	struct siwx91x_dev *sidev = dev->data;
 	sl_wifi_interface_t interface;
 	sl_wifi_ssid_t ssid = { };
@@ -573,6 +583,12 @@ static int siwx91x_scan(const struct device *dev, struct wifi_scan_params *z_sca
 			return -EINVAL;
 		}
 
+		ret = sl_wifi_set_roam_configuration(interface, &roam_configuration);
+		if (ret != SL_STATUS_OK) {
+			LOG_ERR("roaming configuration failed with status %x", ret);
+			return -EINVAL;
+		}
+
 		sl_scan_config.type = SL_WIFI_SCAN_TYPE_ADV_SCAN;
 		sl_scan_config.periodic_scan_interval =
 			CONFIG_WIFI_SILABS_SIWX91X_ADV_SCAN_PERIODICITY;

soc/silabs/silabs_siwx91x/siwg917/nwp.c

@@ -45,6 +45,11 @@ int siwg91x_get_nwp_config(int wifi_oper_mode, sl_wifi_device_configuration_t *g
 	if (wifi_oper_mode == SL_SI91X_CLIENT_MODE) {
 		boot_config->oper_mode = SL_SI91X_CLIENT_MODE;
 
+		if (IS_ENABLED(CONFIG_WIFI_SILABS_SIWX91X_ROAMING_USE_DEAUTH)) {
+			boot_config->custom_feature_bit_map |=
+				SL_SI91X_CUSTOM_FEAT_ROAM_WITH_DEAUTH_OR_NULL_DATA;
+		}
+
 		if (IS_ENABLED(CONFIG_WIFI_SILABS_SIWX91X) &&
 		    IS_ENABLED(CONFIG_BT_SILABS_SIWX91X)) {
 			boot_config->coex_mode = SL_SI91X_WLAN_BLE_MODE;