1 /*
2  * Copyright (c) 2025, sakumisu
3  *
4  * SPDX-License-Identifier: Apache-2.0
5  */
6 #include <rtthread.h>
7 #include <rtdevice.h>
8 
9 #include "usbd_core.h"
10 #include "usbd_cdc_acm.h"
11 
12 #define DEV_FORMAT_CDC_ACM "usb-acm%d"
13 
14 #ifndef CONFIG_USBDEV_MAX_CDC_ACM_CLASS
15 #define CONFIG_USBDEV_MAX_CDC_ACM_CLASS (4)
16 #endif
17 
18 #ifndef CONFIG_USBDEV_SERIAL_RX_BUFSIZE
19 #define CONFIG_USBDEV_SERIAL_RX_BUFSIZE (2048)
20 #endif
21 
22 struct usbd_serial {
23     struct rt_device parent;
24     uint8_t busid;
25     uint8_t in_ep;
26     uint8_t out_ep;
27     struct usbd_interface intf_ctrl;
28     struct usbd_interface intf_data;
29     usb_osal_sem_t tx_done;
30     uint8_t minor;
31     char name[32];
32     struct rt_ringbuffer rx_rb;
33     rt_uint8_t rx_rb_buffer[CONFIG_USBDEV_SERIAL_RX_BUFSIZE];
34 };
35 
36 static uint32_t g_devinuse = 0;
37 
38 static USB_NOCACHE_RAM_SECTION USB_MEM_ALIGNX uint8_t g_usbd_serial_cdc_acm_rx_buf[CONFIG_USBDEV_MAX_CDC_ACM_CLASS][USB_ALIGN_UP(512, CONFIG_USB_ALIGN_SIZE)];
39 
40 static struct usbd_serial g_usbd_serial_cdc_acm[CONFIG_USBDEV_MAX_CDC_ACM_CLASS];
41 
usbd_serial_alloc(void)42 static struct usbd_serial *usbd_serial_alloc(void)
43 {
44     uint8_t devno;
45     struct usbd_serial *serial;
46 
47     for (devno = 0; devno < CONFIG_USBDEV_MAX_CDC_ACM_CLASS; devno++) {
48         if ((g_devinuse & (1U << devno)) == 0) {
49             g_devinuse |= (1U << devno);
50 
51             serial = &g_usbd_serial_cdc_acm[devno];
52             memset(serial, 0, sizeof(struct usbd_serial));
53             serial->minor = devno;
54             snprintf(serial->name, CONFIG_USBHOST_DEV_NAMELEN, DEV_FORMAT_CDC_ACM, serial->minor);
55             return serial;
56         }
57     }
58     return NULL;
59 }
60 
usbd_serial_free(struct usbd_serial * serial)61 static void usbd_serial_free(struct usbd_serial *serial)
62 {
63     uint8_t devno = serial->minor;
64 
65     if (devno < 32) {
66         g_devinuse &= ~(1U << devno);
67     }
68     memset(serial, 0, sizeof(struct usbd_serial));
69 }
70 
usbd_serial_open(struct rt_device * dev,rt_uint16_t oflag)71 static rt_err_t usbd_serial_open(struct rt_device *dev, rt_uint16_t oflag)
72 {
73     struct usbd_serial *serial;
74 
75     RT_ASSERT(dev != RT_NULL);
76 
77     serial = (struct usbd_serial *)dev;
78 
79     if (!usb_device_is_configured(serial->busid)) {
80         USB_LOG_ERR("USB device is not configured\n");
81         return -RT_EPERM;
82     }
83 
84     usbd_ep_start_read(serial->busid, serial->out_ep,
85                        g_usbd_serial_cdc_acm_rx_buf[serial->minor],
86                        usbd_get_ep_mps(serial->busid, serial->out_ep));
87     return RT_EOK;
88 }
89 
usbd_serial_read(struct rt_device * dev,rt_off_t pos,void * buffer,rt_size_t size)90 static rt_ssize_t usbd_serial_read(struct rt_device *dev,
91                                    rt_off_t pos,
92                                    void *buffer,
93                                    rt_size_t size)
94 {
95     struct usbd_serial *serial;
96 
97     RT_ASSERT(dev != RT_NULL);
98 
99     serial = (struct usbd_serial *)dev;
100 
101     if (!usb_device_is_configured(serial->busid)) {
102         return -RT_EPERM;
103     }
104 
105     return rt_ringbuffer_get(&serial->rx_rb, (rt_uint8_t *)buffer, size);
106 }
107 
usbd_serial_write(struct rt_device * dev,rt_off_t pos,const void * buffer,rt_size_t size)108 static rt_ssize_t usbd_serial_write(struct rt_device *dev,
109                                     rt_off_t pos,
110                                     const void *buffer,
111                                     rt_size_t size)
112 {
113     struct usbd_serial *serial;
114     int ret = 0;
115     rt_uint8_t *align_buf;
116 
117     RT_ASSERT(dev != RT_NULL);
118 
119     serial = (struct usbd_serial *)dev;
120 
121     if (!usb_device_is_configured(serial->busid)) {
122         return -RT_EPERM;
123     }
124     align_buf = (rt_uint8_t *)buffer;
125 
126 #ifdef CONFIG_USB_DCACHE_ENABLE
127     if ((uint32_t)buffer & (CONFIG_USB_ALIGN_SIZE - 1)) {
128         align_buf = rt_malloc_align(size, CONFIG_USB_ALIGN_SIZE);
129         if (!align_buf) {
130             USB_LOG_ERR("serial get align buf failed\n");
131             return 0;
132         }
133 
134         usb_memcpy(align_buf, buffer, size);
135     }
136 #endif
137     usb_osal_sem_reset(serial->tx_done);
138     usbd_ep_start_write(serial->busid, serial->in_ep, align_buf, size);
139     ret = usb_osal_sem_take(serial->tx_done, 3000);
140     if (ret < 0) {
141         USB_LOG_ERR("serial write timeout\n");
142         ret = -RT_ETIMEOUT;
143     } else {
144         ret = size;
145     }
146 
147 #ifdef CONFIG_USB_DCACHE_ENABLE
148     if ((uint32_t)buffer & (CONFIG_USB_ALIGN_SIZE - 1)) {
149         rt_free_align(align_buf);
150     }
151 #endif
152 
153     return ret;
154 }
155 
156 #ifdef RT_USING_DEVICE_OPS
157 const static struct rt_device_ops usbd_serial_ops = {
158     NULL,
159     usbd_serial_open,
160     NULL,
161     usbd_serial_read,
162     usbd_serial_write,
163     NULL
164 };
165 #endif
166 
usbd_serial_register(struct usbd_serial * serial,void * data)167 rt_err_t usbd_serial_register(struct usbd_serial *serial,
168                               void *data)
169 {
170     rt_err_t ret;
171     struct rt_device *device;
172     RT_ASSERT(serial != RT_NULL);
173 
174     device = &(serial->parent);
175 
176     device->type = RT_Device_Class_Char;
177     device->rx_indicate = RT_NULL;
178     device->tx_complete = RT_NULL;
179 
180 #ifdef RT_USING_DEVICE_OPS
181     device->ops = &usbd_serial_ops;
182 #else
183     device->init = NULL;
184     device->open = usbd_serial_open;
185     device->close = NULL;
186     device->read = usbd_serial_read;
187     device->write = usbd_serial_write;
188     device->control = NULL;
189 #endif
190     device->user_data = data;
191 
192     /* register a character device */
193     ret = rt_device_register(device, serial->name, RT_DEVICE_FLAG_RDWR | RT_DEVICE_FLAG_INT_RX | RT_DEVICE_FLAG_REMOVABLE);
194 
195 #ifdef RT_USING_POSIX_DEVIO
196     /* set fops */
197     device->fops = NULL;
198 #endif
199     rt_ringbuffer_init(&serial->rx_rb, serial->rx_rb_buffer, sizeof(serial->rx_rb_buffer));
200 
201     return ret;
202 }
203 
usbd_cdc_acm_bulk_out(uint8_t busid,uint8_t ep,uint32_t nbytes)204 void usbd_cdc_acm_bulk_out(uint8_t busid, uint8_t ep, uint32_t nbytes)
205 {
206     struct usbd_serial *serial;
207 
208     for (uint8_t devno = 0; devno < CONFIG_USBDEV_MAX_CDC_ACM_CLASS; devno++) {
209         serial = &g_usbd_serial_cdc_acm[devno];
210         if (serial->out_ep == ep) {
211             rt_ringbuffer_put(&serial->rx_rb, g_usbd_serial_cdc_acm_rx_buf[serial->minor], nbytes);
212             usbd_ep_start_read(serial->busid, serial->out_ep,
213                 g_usbd_serial_cdc_acm_rx_buf[serial->minor],
214                 usbd_get_ep_mps(serial->busid, serial->out_ep));
215 
216             if (serial->parent.rx_indicate) {
217                 serial->parent.rx_indicate(&serial->parent, nbytes);
218             }
219             break;
220         }
221     }
222 }
223 
usbd_cdc_acm_bulk_in(uint8_t busid,uint8_t ep,uint32_t nbytes)224 void usbd_cdc_acm_bulk_in(uint8_t busid, uint8_t ep, uint32_t nbytes)
225 {
226     struct usbd_serial *serial;
227 
228     if ((nbytes % usbd_get_ep_mps(busid, ep)) == 0 && nbytes) {
229         /* send zlp */
230         usbd_ep_start_write(busid, ep, NULL, 0);
231     } else {
232         for (uint8_t devno = 0; devno < CONFIG_USBDEV_MAX_CDC_ACM_CLASS; devno++) {
233             serial = &g_usbd_serial_cdc_acm[devno];
234             if ((serial->in_ep == ep) && serial->tx_done) {
235                 usb_osal_sem_give(serial->tx_done);
236                 break;
237             }
238         }
239     }
240 }
241 
usbd_cdc_acm_serial_init(uint8_t busid,uint8_t in_ep,uint8_t out_ep)242 void usbd_cdc_acm_serial_init(uint8_t busid, uint8_t in_ep, uint8_t out_ep)
243 {
244     struct usbd_serial *serial;
245 
246     struct usbd_endpoint cdc_out_ep = {
247         .ep_addr = out_ep,
248         .ep_cb = usbd_cdc_acm_bulk_out
249     };
250 
251     struct usbd_endpoint cdc_in_ep = {
252         .ep_addr = in_ep,
253         .ep_cb = usbd_cdc_acm_bulk_in
254     };
255 
256     serial = usbd_serial_alloc();
257     if (serial == NULL) {
258         USB_LOG_ERR("No more serial device available\n");
259         return;
260     }
261 
262     serial->busid = busid;
263     serial->in_ep = in_ep;
264     serial->out_ep = out_ep;
265     serial->tx_done = usb_osal_sem_create(0);
266 
267     usbd_add_interface(busid, usbd_cdc_acm_init_intf(busid, &serial->intf_ctrl));
268     usbd_add_interface(busid, usbd_cdc_acm_init_intf(busid, &serial->intf_data));
269     usbd_add_endpoint(busid, &cdc_out_ep);
270     usbd_add_endpoint(busid, &cdc_in_ep);
271 
272     if (usbd_serial_register(serial, NULL) != RT_EOK) {
273         USB_LOG_ERR("Failed to register serial device\n");
274         usbd_serial_free(serial);
275         return;
276     }
277 
278     USB_LOG_INFO("USB CDC ACM Serial Device %s initialized\n", serial->name);
279 }
280