1 /*
2  * Copyright (c) 2025, sakumisu
3  *
4  * SPDX-License-Identifier: Apache-2.0
5  */
6 #include "usbd_core.h"
7 #include "usbd_cdc_acm.h"
8 #include "chry_ringbuffer.h"
9 #include <mavlink.h>
10 
11 /*!< endpoint address */
12 #define CDC_IN_EP          0x81
13 #define CDC_OUT_EP         0x02
14 #define CDC_INT_EP         0x83
15 
16 #define USBD_VID           0xFFFF
17 #define USBD_PID           0xFFFF
18 #define USBD_MAX_POWER     100
19 #define USBD_LANGID_STRING 1033
20 
21 /*!< config descriptor size */
22 #define USB_CONFIG_SIZE    (9 + CDC_ACM_DESCRIPTOR_LEN)
23 
24 #ifdef CONFIG_USB_HS
25 #define CDC_MAX_MPS 512
26 #else
27 #define CDC_MAX_MPS 64
28 #endif
29 
30 #ifdef CONFIG_USBDEV_ADVANCE_DESC
31 static const uint8_t device_descriptor[] = {
32     USB_DEVICE_DESCRIPTOR_INIT(USB_2_0, 0xEF, 0x02, 0x01, USBD_VID, USBD_PID, 0x0100, 0x01)
33 };
34 
35 static const uint8_t config_descriptor[] = {
36     USB_CONFIG_DESCRIPTOR_INIT(USB_CONFIG_SIZE, 0x02, 0x01, USB_CONFIG_BUS_POWERED, USBD_MAX_POWER),
37     CDC_ACM_DESCRIPTOR_INIT(0x00, CDC_INT_EP, CDC_OUT_EP, CDC_IN_EP, CDC_MAX_MPS, 0x02)
38 };
39 
40 static const uint8_t device_quality_descriptor[] = {
41     ///////////////////////////////////////
42     /// device qualifier descriptor
43     ///////////////////////////////////////
44     0x0a,
45     USB_DESCRIPTOR_TYPE_DEVICE_QUALIFIER,
46     0x00,
47     0x02,
48     0x00,
49     0x00,
50     0x00,
51     0x40,
52     0x00,
53     0x00,
54 };
55 
56 static const char *string_descriptors[] = {
57     (const char[]){ 0x09, 0x04 }, /* Langid */
58     "CherryUSB",                  /* Manufacturer */
59     "CherryUSB CDC DEMO",         /* Product */
60     "2022123456",                 /* Serial Number */
61 };
62 
device_descriptor_callback(uint8_t speed)63 static const uint8_t *device_descriptor_callback(uint8_t speed)
64 {
65     return device_descriptor;
66 }
67 
config_descriptor_callback(uint8_t speed)68 static const uint8_t *config_descriptor_callback(uint8_t speed)
69 {
70     return config_descriptor;
71 }
72 
device_quality_descriptor_callback(uint8_t speed)73 static const uint8_t *device_quality_descriptor_callback(uint8_t speed)
74 {
75     return device_quality_descriptor;
76 }
77 
string_descriptor_callback(uint8_t speed,uint8_t index)78 static const char *string_descriptor_callback(uint8_t speed, uint8_t index)
79 {
80     if (index > 3) {
81         return NULL;
82     }
83     return string_descriptors[index];
84 }
85 
86 const struct usb_descriptor cdc_descriptor = {
87     .device_descriptor_callback = device_descriptor_callback,
88     .config_descriptor_callback = config_descriptor_callback,
89     .device_quality_descriptor_callback = device_quality_descriptor_callback,
90     .string_descriptor_callback = string_descriptor_callback
91 };
92 #else
93 /*!< global descriptor */
94 static const uint8_t cdc_descriptor[] = {
95     USB_DEVICE_DESCRIPTOR_INIT(USB_2_0, 0xEF, 0x02, 0x01, USBD_VID, USBD_PID, 0x0100, 0x01),
96     USB_CONFIG_DESCRIPTOR_INIT(USB_CONFIG_SIZE, 0x02, 0x01, USB_CONFIG_BUS_POWERED, USBD_MAX_POWER),
97     CDC_ACM_DESCRIPTOR_INIT(0x00, CDC_INT_EP, CDC_OUT_EP, CDC_IN_EP, CDC_MAX_MPS, 0x02),
98     ///////////////////////////////////////
99     /// string0 descriptor
100     ///////////////////////////////////////
101     USB_LANGID_INIT(USBD_LANGID_STRING),
102     ///////////////////////////////////////
103     /// string1 descriptor
104     ///////////////////////////////////////
105     0x14,                       /* bLength */
106     USB_DESCRIPTOR_TYPE_STRING, /* bDescriptorType */
107     'C', 0x00,                  /* wcChar0 */
108     'h', 0x00,                  /* wcChar1 */
109     'e', 0x00,                  /* wcChar2 */
110     'r', 0x00,                  /* wcChar3 */
111     'r', 0x00,                  /* wcChar4 */
112     'y', 0x00,                  /* wcChar5 */
113     'U', 0x00,                  /* wcChar6 */
114     'S', 0x00,                  /* wcChar7 */
115     'B', 0x00,                  /* wcChar8 */
116     ///////////////////////////////////////
117     /// string2 descriptor
118     ///////////////////////////////////////
119     0x26,                       /* bLength */
120     USB_DESCRIPTOR_TYPE_STRING, /* bDescriptorType */
121     'C', 0x00,                  /* wcChar0 */
122     'h', 0x00,                  /* wcChar1 */
123     'e', 0x00,                  /* wcChar2 */
124     'r', 0x00,                  /* wcChar3 */
125     'r', 0x00,                  /* wcChar4 */
126     'y', 0x00,                  /* wcChar5 */
127     'U', 0x00,                  /* wcChar6 */
128     'S', 0x00,                  /* wcChar7 */
129     'B', 0x00,                  /* wcChar8 */
130     ' ', 0x00,                  /* wcChar9 */
131     'C', 0x00,                  /* wcChar10 */
132     'D', 0x00,                  /* wcChar11 */
133     'C', 0x00,                  /* wcChar12 */
134     ' ', 0x00,                  /* wcChar13 */
135     'D', 0x00,                  /* wcChar14 */
136     'E', 0x00,                  /* wcChar15 */
137     'M', 0x00,                  /* wcChar16 */
138     'O', 0x00,                  /* wcChar17 */
139     ///////////////////////////////////////
140     /// string3 descriptor
141     ///////////////////////////////////////
142     0x16,                       /* bLength */
143     USB_DESCRIPTOR_TYPE_STRING, /* bDescriptorType */
144     '2', 0x00,                  /* wcChar0 */
145     '0', 0x00,                  /* wcChar1 */
146     '2', 0x00,                  /* wcChar2 */
147     '2', 0x00,                  /* wcChar3 */
148     '1', 0x00,                  /* wcChar4 */
149     '2', 0x00,                  /* wcChar5 */
150     '3', 0x00,                  /* wcChar6 */
151     '4', 0x00,                  /* wcChar7 */
152     '5', 0x00,                  /* wcChar8 */
153     '6', 0x00,                  /* wcChar9 */
154 #ifdef CONFIG_USB_HS
155     ///////////////////////////////////////
156     /// device qualifier descriptor
157     ///////////////////////////////////////
158     0x0a,
159     USB_DESCRIPTOR_TYPE_DEVICE_QUALIFIER,
160     0x00,
161     0x02,
162     0x00,
163     0x00,
164     0x00,
165     0x40,
166     0x00,
167     0x00,
168 #endif
169     0x00
170 };
171 #endif
172 
173 chry_ringbuffer_t usb_rx_rb;
174 uint8_t usb_rx_buffer[2048];
175 
176 USB_NOCACHE_RAM_SECTION USB_MEM_ALIGNX uint8_t temp_rx_buffer[512];
177 USB_NOCACHE_RAM_SECTION USB_MEM_ALIGNX uint8_t usb_tx_buffer[MAVLINK_MAX_PACKET_LEN];
178 
179 volatile bool ep_tx_busy_flag = false;
180 
usbd_event_handler(uint8_t busid,uint8_t event)181 static void usbd_event_handler(uint8_t busid, uint8_t event)
182 {
183     switch (event) {
184         case USBD_EVENT_RESET:
185             break;
186         case USBD_EVENT_CONNECTED:
187             break;
188         case USBD_EVENT_DISCONNECTED:
189             break;
190         case USBD_EVENT_RESUME:
191             break;
192         case USBD_EVENT_SUSPEND:
193             break;
194         case USBD_EVENT_CONFIGURED:
195             ep_tx_busy_flag = false;
196             /* setup first out ep read transfer */
197             usbd_ep_start_read(busid, CDC_OUT_EP, temp_rx_buffer, usbd_get_ep_mps(busid, CDC_OUT_EP));
198             break;
199         case USBD_EVENT_SET_REMOTE_WAKEUP:
200             break;
201         case USBD_EVENT_CLR_REMOTE_WAKEUP:
202             break;
203 
204         default:
205             break;
206     }
207 }
208 
usbd_cdc_acm_bulk_out(uint8_t busid,uint8_t ep,uint32_t nbytes)209 void usbd_cdc_acm_bulk_out(uint8_t busid, uint8_t ep, uint32_t nbytes)
210 {
211     USB_LOG_RAW("actual out len:%d\r\n", (unsigned int)nbytes);
212 
213     chry_ringbuffer_write(&usb_rx_rb, temp_rx_buffer, nbytes);
214     usbd_ep_start_read(busid, CDC_OUT_EP, temp_rx_buffer, usbd_get_ep_mps(busid, CDC_OUT_EP));
215 }
216 
usbd_cdc_acm_bulk_in(uint8_t busid,uint8_t ep,uint32_t nbytes)217 void usbd_cdc_acm_bulk_in(uint8_t busid, uint8_t ep, uint32_t nbytes)
218 {
219     USB_LOG_RAW("actual in len:%d\r\n", (unsigned int)nbytes);
220 
221     if ((nbytes % usbd_get_ep_mps(busid, ep)) == 0 && nbytes) {
222         /* send zlp */
223         usbd_ep_start_write(busid, CDC_IN_EP, NULL, 0);
224     } else {
225         ep_tx_busy_flag = false;
226     }
227 }
228 
229 /*!< endpoint call back */
230 struct usbd_endpoint cdc_out_ep = {
231     .ep_addr = CDC_OUT_EP,
232     .ep_cb = usbd_cdc_acm_bulk_out
233 };
234 
235 struct usbd_endpoint cdc_in_ep = {
236     .ep_addr = CDC_IN_EP,
237     .ep_cb = usbd_cdc_acm_bulk_in
238 };
239 
240 static struct usbd_interface intf0;
241 static struct usbd_interface intf1;
242 
cdc_acm_mavlink_init(uint8_t busid,uintptr_t reg_base)243 void cdc_acm_mavlink_init(uint8_t busid, uintptr_t reg_base)
244 {
245     chry_ringbuffer_init(&usb_rx_rb, usb_rx_buffer, sizeof(usb_rx_buffer));
246 #ifdef CONFIG_USBDEV_ADVANCE_DESC
247     usbd_desc_register(busid, &cdc_descriptor);
248 #else
249     usbd_desc_register(busid, cdc_descriptor);
250 #endif
251     usbd_add_interface(busid, usbd_cdc_acm_init_intf(busid, &intf0));
252     usbd_add_interface(busid, usbd_cdc_acm_init_intf(busid, &intf1));
253     usbd_add_endpoint(busid, &cdc_out_ep);
254     usbd_add_endpoint(busid, &cdc_in_ep);
255     usbd_initialize(busid, reg_base, usbd_event_handler);
256 }
257 
cdc_acm_mavlink_write(uint8_t * data,uint32_t len)258 void cdc_acm_mavlink_write(uint8_t *data, uint32_t len)
259 {
260     if (!usb_device_is_configured(0)) {
261         return;
262     }
263     ep_tx_busy_flag = true;
264     usbd_ep_start_write(0, CDC_IN_EP, data, len);
265     while (ep_tx_busy_flag) {
266     }
267 }
268 
send_heartbeat(void)269 void send_heartbeat(void)
270 {
271     mavlink_message_t message;
272 
273     const uint8_t system_id = 42;
274     const uint8_t base_mode = 0;
275     const uint8_t custom_mode = 0;
276     mavlink_msg_heartbeat_pack_chan(
277         system_id,
278         MAV_COMP_ID_PERIPHERAL,
279         MAVLINK_COMM_0,
280         &message,
281         MAV_TYPE_GENERIC,
282         MAV_AUTOPILOT_GENERIC,
283         base_mode,
284         custom_mode,
285         MAV_STATE_STANDBY);
286 
287     const int len = mavlink_msg_to_send_buffer(usb_tx_buffer, &message);
288     cdc_acm_mavlink_write(usb_tx_buffer, len);
289 }
290 
handle_heartbeat(const mavlink_message_t * message)291 void handle_heartbeat(const mavlink_message_t *message)
292 {
293     mavlink_heartbeat_t heartbeat;
294     mavlink_msg_heartbeat_decode(message, &heartbeat);
295 
296     USB_LOG_RAW("Got heartbeat from ");
297     switch (heartbeat.autopilot) {
298         case MAV_AUTOPILOT_GENERIC:
299             USB_LOG_RAW("generic");
300             break;
301         case MAV_AUTOPILOT_ARDUPILOTMEGA:
302             USB_LOG_RAW("ArduPilot");
303             break;
304         case MAV_AUTOPILOT_PX4:
305             USB_LOG_RAW("PX4");
306             break;
307         default:
308             USB_LOG_RAW("other");
309             break;
310     }
311     USB_LOG_RAW(" autopilot\n");
312 
313     send_heartbeat();
314 }
315 
mavlink_polling(void)316 void mavlink_polling(void)
317 {
318     uint8_t ch;
319     bool ret;
320     mavlink_message_t message;
321     mavlink_status_t status;
322 
323     ret = chry_ringbuffer_read_byte(&usb_rx_rb, &ch);
324     if (ret) {
325         if (mavlink_parse_char(MAVLINK_COMM_0, ch, &message, &status) == 1) {
326             USB_LOG_INFO(
327                 "Received message %d from %d/%d\n",
328                 message.msgid, message.sysid, message.compid);
329 
330             switch (message.msgid) {
331                 case MAVLINK_MSG_ID_HEARTBEAT:
332                     handle_heartbeat(&message);
333                     break;
334             }
335         }
336     }
337 }