style: subsys: adjust return usage in void functions

For code clarity, this commit adjusts the use of `return` statements
in functions with a void return type as follows:
- Transform `return foo();` into separate statements:
  `foo();`
  `return;`
- Remove unnecessary `return` statements when
  they don't affect control flow.

Signed-off-by: Pisit Sawangvonganan <pisit@ndrsolution.com>

subsys/bluetooth/controller/ll_sw/nordic/lll/lll_adv.c

@@ -1382,7 +1382,7 @@ static void isr_done(void *param)
 
 			err = isr_close_adv_mesh();
 			if (err) {
-				return 0;
+				return;
 			}
 		}
 #endif /* CONFIG_BT_HCI_MESH_EXT */

subsys/bluetooth/controller/ll_sw/openisa/lll/lll_adv.c

@@ -716,7 +716,7 @@ static void isr_done(void *param)
 
 			err = isr_close_adv_mesh();
 			if (err) {
-				return 0;
+				return;
 			}
 		}
 #endif /* CONFIG_BT_HCI_MESH_EXT */

subsys/bluetooth/controller/ll_sw/ull_conn.c

@@ -2344,7 +2344,7 @@ static inline void dle_max_time_get(struct ll_conn *conn, uint16_t *max_rx_time,
 void ull_dle_max_time_get(struct ll_conn *conn, uint16_t *max_rx_time,
 				    uint16_t *max_tx_time)
 {
-	return dle_max_time_get(conn, max_rx_time, max_tx_time);
+	dle_max_time_get(conn, max_rx_time, max_tx_time);
 }
 
 /*

subsys/logging/log_msg.c

@@ -337,7 +337,7 @@ static inline void z_vrfy_z_log_msg_static_create(const void *source,
 			      const struct log_msg_desc desc,
 			      uint8_t *package, const void *data)
 {
-	return z_impl_z_log_msg_static_create(source, desc, package, data);
+	z_impl_z_log_msg_static_create(source, desc, package, data);
 }
 #include <zephyr/syscalls/z_log_msg_static_create_mrsh.c>
 #endif

subsys/mgmt/ec_host_cmd/backends/ec_host_cmd_backend_shi_npcx.c

@@ -417,7 +417,8 @@ static void shi_npcx_handle_host_package(const struct device *dev)
 
 	/* Read remaining bytes from input buffer */
 	if (!shi_npcx_read_inbuf_wait(dev, remain_bytes)) {
-		return shi_npcx_bad_received_data(dev);
+		shi_npcx_bad_received_data(dev);
+		return;
 	}
 
 	/* Move to processing state */
@@ -464,7 +465,8 @@ static void shi_npcx_parse_header(const struct device *dev)
 
 	/* Wait for version, command, length bytes */
 	if (!shi_npcx_read_inbuf_wait(dev, 3)) {
-		return shi_npcx_bad_received_data(dev);
+		shi_npcx_bad_received_data(dev);
+		return;
 	}
 
 	if (data->in_msg[0] == EC_HOST_REQUEST_VERSION) {
@@ -480,13 +482,15 @@ static void shi_npcx_parse_header(const struct device *dev)
 
 		/* Wait for the rest of the command header */
 		if (!shi_npcx_read_inbuf_wait(dev, sizeof(*r) - 3)) {
-			return shi_npcx_bad_received_data(dev);
+			shi_npcx_bad_received_data(dev);
+			return;
 		}
 
 		/* Check how big the packet should be */
 		pkt_size = shi_npcx_host_request_expected_size(r);
 		if (pkt_size == 0 || pkt_size > sizeof(data->in_msg)) {
-			return shi_npcx_bad_received_data(dev);
+			shi_npcx_bad_received_data(dev);
+			return;
 		}
 
 		/* Computing total bytes need to receive */
@@ -495,7 +499,8 @@ static void shi_npcx_parse_header(const struct device *dev)
 		shi_npcx_handle_host_package(dev);
 	} else {
 		/* Invalid version number */
-		return shi_npcx_bad_received_data(dev);
+		shi_npcx_bad_received_data(dev);
+		return;
 	}
 }
 
@@ -632,7 +637,8 @@ static void shi_npcx_handle_input_buf_half_full(const struct device *dev)
 	if (data->state == SHI_STATE_RECEIVING) {
 		/* Read data from input to msg buffer */
 		shi_npcx_read_half_inbuf(dev);
-		return shi_npcx_handle_host_package(dev);
+		shi_npcx_handle_host_package(dev);
+		return;
 	} else if (data->state == SHI_STATE_SENDING) {
 		/* Write data from msg buffer to output buffer */
 		if (data->tx_buf == inst->OBUF + SHI_OBUF_FULL_SIZE) {
@@ -658,7 +664,8 @@ static void shi_npcx_handle_input_buf_full(const struct device *dev)
 		shi_npcx_read_half_inbuf(dev);
 		/* Read to bottom address again */
 		data->rx_buf = inst->IBUF;
-		return shi_npcx_handle_host_package(dev);
+		shi_npcx_handle_host_package(dev);
+		return;
 	} else if (data->state == SHI_STATE_SENDING) {
 		/* Write data from msg buffer to output buffer */
 		if (data->tx_buf == inst->OBUF + SHI_OBUF_HALF_SIZE) {
@@ -729,7 +736,8 @@ static void shi_npcx_isr(const struct device *dev)
 		 * Mark not ready to abort next transaction
 		 */
 		LOG_DBG("CSH-");
-		return shi_npcx_handle_cs_deassert(dev);
+		shi_npcx_handle_cs_deassert(dev);
+		return;
 	}
 #endif
 
@@ -752,7 +760,8 @@ static void shi_npcx_isr(const struct device *dev)
 	 * Transaction is processing.
 	 */
 	if (IS_BIT_SET(stat, NPCX_EVSTAT_IBHF)) {
-		return shi_npcx_handle_input_buf_half_full(dev);
+		shi_npcx_handle_input_buf_half_full(dev);
+		return;
 	}
 
 	/*
@@ -760,7 +769,8 @@ static void shi_npcx_isr(const struct device *dev)
 	 * Transaction is processing.
 	 */
 	if (IS_BIT_SET(stat, NPCX_EVSTAT_IBF)) {
-		return shi_npcx_handle_input_buf_full(dev);
+		shi_npcx_handle_input_buf_full(dev);
+		return;
 	}
 }
 

subsys/net/lib/dhcpv4/dhcpv4.c

@@ -1813,7 +1813,7 @@ int net_dhcpv4_remove_option_vendor_callback(struct net_dhcpv4_option_callback *
 
 void net_dhcpv4_start(struct net_if *iface)
 {
-	return dhcpv4_start_internal(iface, true);
+	dhcpv4_start_internal(iface, true);
 }
 
 void net_dhcpv4_stop(struct net_if *iface)

subsys/net/lib/lwm2m/lwm2m_message_handling.c

@@ -2812,7 +2812,7 @@ void lwm2m_udp_receive(struct lwm2m_ctx *client_ctx, uint8_t *buf, uint16_t buf_
 		if (has_block2 && IS_ENABLED(CONFIG_LWM2M_COAP_BLOCK_TRANSFER)) {
 			msg = find_ongoing_block2_tx();
 			if (msg) {
-				return handle_ongoing_block2_tx(msg, &response);
+				handle_ongoing_block2_tx(msg, &response);
 			}
 			return;
 		}

subsys/net/lib/sockets/getaddrinfo.c

@@ -472,7 +472,8 @@ int zsock_getaddrinfo(const char *host, const char *service,
 void zsock_freeaddrinfo(struct zsock_addrinfo *ai)
 {
 	if (IS_ENABLED(CONFIG_NET_SOCKETS_OFFLOAD)) {
-		return socket_offload_freeaddrinfo(ai);
+		socket_offload_freeaddrinfo(ai);
+		return;
 	}
 
 	free(ai);

subsys/net/lib/sockets/socket_offload.c

@@ -37,5 +37,5 @@ void socket_offload_freeaddrinfo(struct zsock_addrinfo *res)
 	__ASSERT_NO_MSG(dns_offload);
 	__ASSERT_NO_MSG(dns_offload->freeaddrinfo);
 
-	return dns_offload->freeaddrinfo(res);
+	dns_offload->freeaddrinfo(res);
 }

subsys/shell/backends/shell_telnet.c

@@ -480,7 +480,8 @@ static void telnet_server_cb(struct k_work *work)
 		NET_ERR("Telnet socket %d error (%d)", evt->event.fd, sock_error);
 
 		if (evt->event.fd == sh_telnet->fds[SOCK_ID_CLIENT].fd) {
-			return telnet_end_client_connection();
+			telnet_end_client_connection();
+			return;
 		}
 
 		goto error;
@@ -491,11 +492,14 @@ static void telnet_server_cb(struct k_work *work)
 	}
 
 	if (evt->event.fd == sh_telnet->fds[SOCK_ID_IPV4_LISTEN].fd) {
-		return telnet_accept(&sh_telnet->fds[SOCK_ID_IPV4_LISTEN]);
+		telnet_accept(&sh_telnet->fds[SOCK_ID_IPV4_LISTEN]);
+		return;
 	} else if (evt->event.fd == sh_telnet->fds[SOCK_ID_IPV6_LISTEN].fd) {
-		return telnet_accept(&sh_telnet->fds[SOCK_ID_IPV6_LISTEN]);
+		telnet_accept(&sh_telnet->fds[SOCK_ID_IPV6_LISTEN]);
+		return;
 	} else if (evt->event.fd == sh_telnet->fds[SOCK_ID_CLIENT].fd) {
-		return telnet_recv(&sh_telnet->fds[SOCK_ID_CLIENT]);
+		telnet_recv(&sh_telnet->fds[SOCK_ID_CLIENT]);
+		return;
 	}
 
 	NET_ERR("Unexpected FD received for telnet, restarting service.");