feat: 添加CDC协议通信模块支持

- 集成nanopb库用于protobuf序列化
- 创建cdc_wrapper_module.c实现帧解析功能
- 实现protocol_module.c处理协议编解码
- 定义device_comm.proto通信协议
- 修改CMakeLists.txt添加protobuf源文件
- 更新配置启用NANOPB支持
- 移除usb_cdc_module中基于行的处理逻辑

src/protocol_module.c

@@ -0,0 +1,133 @@
+#include <errno.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#include <zephyr/logging/log.h>
+
+#include <pb_decode.h>
+#include <pb_encode.h>
+
+#include <proto/device_comm.pb.h>
+
+#include "protocol_module.h"
+
+LOG_MODULE_REGISTER(protocol_module, LOG_LEVEL_INF);
+
+#define PROTOCOL_VERSION 1U
+#define PROTOCOL_VENDOR_ID 0x1915U
+#define PROTOCOL_PRODUCT_ID 0x52F0U
+#define PROTOCOL_FIRMWARE_MAJOR 0U
+#define PROTOCOL_FIRMWARE_MINOR 0U
+#define PROTOCOL_CAPABILITY_FLAGS 0U
+
+static bool type_matches_body(uint8_t type, const CdcPacketBody *body)
+{
+	switch (type) {
+	case CDC_PROTO_TYPE_HELLO_REQ:
+		return body->which_body == CdcPacketBody_hello_req_tag;
+	case CDC_PROTO_TYPE_HELLO_RSP:
+		return body->which_body == CdcPacketBody_hello_rsp_tag;
+	default:
+		return false;
+	}
+}
+
+static int decode_body(const uint8_t *payload, size_t payload_len,
+		       CdcPacketBody *body)
+{
+	pb_istream_t stream;
+
+	if ((payload == NULL) || (body == NULL)) {
+		return -EINVAL;
+	}
+
+	*body = (CdcPacketBody)CdcPacketBody_init_zero;
+	stream = pb_istream_from_buffer(payload, payload_len);
+
+	if (!pb_decode(&stream, CdcPacketBody_fields, body)) {
+		LOG_WRN("pb_decode failed: %s", PB_GET_ERROR(&stream));
+		return -EBADMSG;
+	}
+
+	return 0;
+}
+
+static int encode_hello_rsp(uint8_t *rsp_payload, size_t rsp_payload_buf_size,
+			    size_t *rsp_payload_len)
+{
+	CdcPacketBody body = CdcPacketBody_init_zero;
+	pb_ostream_t stream;
+
+	if ((rsp_payload == NULL) || (rsp_payload_len == NULL)) {
+		return -EINVAL;
+	}
+
+	body.which_body = CdcPacketBody_hello_rsp_tag;
+	body.body.hello_rsp.protocol_version = PROTOCOL_VERSION;
+	body.body.hello_rsp.vendor_id = PROTOCOL_VENDOR_ID;
+	body.body.hello_rsp.product_id = PROTOCOL_PRODUCT_ID;
+	body.body.hello_rsp.firmware_major = PROTOCOL_FIRMWARE_MAJOR;
+	body.body.hello_rsp.firmware_minor = PROTOCOL_FIRMWARE_MINOR;
+	body.body.hello_rsp.capability_flags = PROTOCOL_CAPABILITY_FLAGS;
+
+	stream = pb_ostream_from_buffer(rsp_payload, rsp_payload_buf_size);
+
+	if (!pb_encode(&stream, CdcPacketBody_fields, &body)) {
+		LOG_WRN("pb_encode failed: %s", PB_GET_ERROR(&stream));
+		return -EIO;
+	}
+
+	*rsp_payload_len = stream.bytes_written;
+	return 0;
+}
+
+int protocol_module_process_cdc_packet(uint8_t req_type,
+				       const uint8_t *req_payload,
+				       size_t req_payload_len,
+				       uint8_t *rsp_type,
+				       uint8_t *rsp_payload,
+				       size_t rsp_payload_buf_size,
+				       size_t *rsp_payload_len)
+{
+	CdcPacketBody body;
+	int err;
+
+	if ((rsp_type == NULL) || (rsp_payload == NULL) || (rsp_payload_len == NULL)) {
+		return -EINVAL;
+	}
+
+	err = decode_body(req_payload, req_payload_len, &body);
+	if (err) {
+		return err;
+	}
+
+	if (!type_matches_body(req_type, &body)) {
+		LOG_WRN("CDC type/body mismatch type:0x%02x body_case:%d",
+			req_type, body.which_body);
+		return -EBADMSG;
+	}
+
+	switch (req_type) {
+	case CDC_PROTO_TYPE_HELLO_REQ:
+		LOG_INF("HelloReq protocol_version:%u",
+			body.body.hello_req.protocol_version);
+
+		if (body.body.hello_req.protocol_version != PROTOCOL_VERSION) {
+			LOG_WRN("Unexpected protocol version:%u",
+				body.body.hello_req.protocol_version);
+		}
+
+		err = encode_hello_rsp(rsp_payload, rsp_payload_buf_size, rsp_payload_len);
+		if (err) {
+			return err;
+		}
+
+		*rsp_type = CDC_PROTO_TYPE_HELLO_RSP;
+		return 0;
+
+	default:
+		LOG_WRN("Unsupported CDC protocol type:0x%02x", req_type);
+		return -ENOTSUP;
+	}
+}