feat(platform/rtthread): support cdc acm chardev

Signed-off-by: sakumisu <[email protected]>

1 files changed, 272 insertions, 0 deletions

diff --git a/platform/rtthread/usbd_serial.c b/platform/rtthread/usbd_serial.c
new file mode 100644
index 00000000..5ce62209
--- /dev/null
+++ b/platform/rtthread/usbd_serial.c
@@ -0,0 +1,272 @@
+/*
+ * Copyright (c) 2025, sakumisu
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <rtthread.h>
+#include <rtdevice.h>
+
+#include "usbd_core.h"
+#include "usbd_cdc_acm.h"
+
+#define DEV_FORMAT_CDC_ACM "usb-acm%d"
+
+#ifndef CONFIG_USBDEV_MAX_CDC_ACM_CLASS
+#define CONFIG_USBDEV_MAX_CDC_ACM_CLASS (4)
+#endif
+
+#ifndef CONFIG_USBDEV_SERIAL_RX_BUFSIZE
+#define CONFIG_USBDEV_SERIAL_RX_BUFSIZE (2048)
+#endif
+
+struct usbd_serial {
+    struct rt_device parent;
+    uint8_t busid;
+    uint8_t in_ep;
+    uint8_t out_ep;
+    struct usbd_interface intf_ctrl;
+    struct usbd_interface intf_data;
+    usb_osal_sem_t tx_done;
+    uint8_t minor;
+    char name[32];
+    struct rt_ringbuffer rx_rb;
+    rt_uint8_t rx_rb_buffer[CONFIG_USBDEV_SERIAL_RX_BUFSIZE];
+};
+
+static uint32_t g_devinuse = 0;
+
+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)];
+
+static struct usbd_serial g_usbd_serial_cdc_acm[CONFIG_USBDEV_MAX_CDC_ACM_CLASS];
+
+static struct usbd_serial *usbd_serial_alloc(void)
+{
+    uint8_t devno;
+    struct usbd_serial *serial;
+
+    for (devno = 0; devno < CONFIG_USBDEV_MAX_CDC_ACM_CLASS; devno++) {
+        if ((g_devinuse & (1U << devno)) == 0) {
+            g_devinuse |= (1U << devno);
+
+            serial = &g_usbd_serial_cdc_acm[devno];
+            memset(serial, 0, sizeof(struct usbd_serial));
+            serial->minor = devno;
+            snprintf(serial->name, CONFIG_USBHOST_DEV_NAMELEN, DEV_FORMAT_CDC_ACM, serial->minor);
+            return serial;
+        }
+    }
+    return NULL;
+}
+
+static void usbd_serial_free(struct usbd_serial *serial)
+{
+    uint8_t devno = serial->minor;
+
+    if (devno < 32) {
+        g_devinuse &= ~(1U << devno);
+    }
+    memset(serial, 0, sizeof(struct usbd_serial));
+}
+
+static rt_err_t usbd_serial_open(struct rt_device *dev, rt_uint16_t oflag)
+{
+    struct usbd_serial *serial;
+
+    RT_ASSERT(dev != RT_NULL);
+
+    serial = (struct usbd_serial *)dev;
+
+    if (!usb_device_is_configured(serial->busid)) {
+        USB_LOG_ERR("USB device is not configured\n");
+        return -RT_EPERM;
+    }
+
+    usbd_ep_start_read(serial->busid, serial->out_ep,
+                       g_usbd_serial_cdc_acm_rx_buf[serial->minor],
+                       usbd_get_ep_mps(serial->busid, serial->out_ep));
+    return RT_EOK;
+}
+
+static rt_ssize_t usbd_serial_read(struct rt_device *dev,
+                                   rt_off_t pos,
+                                   void *buffer,
+                                   rt_size_t size)
+{
+    struct usbd_serial *serial;
+
+    RT_ASSERT(dev != RT_NULL);
+
+    serial = (struct usbd_serial *)dev;
+
+    if (!usb_device_is_configured(serial->busid)) {
+        return -RT_EPERM;
+    }
+
+    return rt_ringbuffer_get(&serial->rx_rb, (rt_uint8_t *)buffer, size);
+}
+
+static rt_ssize_t usbd_serial_write(struct rt_device *dev,
+                                    rt_off_t pos,
+                                    const void *buffer,
+                                    rt_size_t size)
+{
+    struct usbd_serial *serial;
+    int ret = 0;
+    rt_uint8_t *align_buf;
+
+    RT_ASSERT(dev != RT_NULL);
+
+    serial = (struct usbd_serial *)dev;
+
+    if (!usb_device_is_configured(serial->busid)) {
+        return -RT_EPERM;
+    }
+    align_buf = (rt_uint8_t *)buffer;
+
+#ifdef RT_USING_CACHE
+    if ((uint32_t)buffer & (CONFIG_USB_ALIGN_SIZE - 1)) {
+        align_buf = rt_malloc_align(size, CONFIG_USB_ALIGN_SIZE);
+        if (!align_buf) {
+            USB_LOG_ERR("serial get align buf failed\n");
+            return 0;
+        }
+
+        usb_memcpy(align_buf, buffer, size);
+    }
+#endif
+    usb_osal_sem_reset(serial->tx_done);
+    usbd_ep_start_write(serial->busid, serial->in_ep, align_buf, size);
+    ret = usb_osal_sem_take(serial->tx_done, 3000);
+    if (ret < 0) {
+        USB_LOG_ERR("serial write timeout\n");
+        ret = -RT_ETIMEOUT;
+    } else {
+        ret = size;
+    }
+
+#ifdef CONFIG_USB_DCACHE_ENABLE
+    if ((uint32_t)buffer & (CONFIG_USB_ALIGN_SIZE - 1)) {
+        rt_free_align(align_buf);
+    }
+#endif
+
+    return ret;
+}
+
+#ifdef RT_USING_DEVICE_OPS
+const static struct rt_device_ops usbd_serial_ops = {
+    NULL,
+    usbd_serial_open,
+    NULL,
+    usbd_serial_read,
+    usbd_serial_write,
+    NULL
+};
+#endif
+
+rt_err_t usbd_serial_register(struct usbd_serial *serial,
+                              void *data)
+{
+    rt_err_t ret;
+    struct rt_device *device;
+    RT_ASSERT(serial != RT_NULL);
+
+    device = &(serial->parent);
+
+    device->type = RT_Device_Class_Char;
+    device->rx_indicate = RT_NULL;
+    device->tx_complete = RT_NULL;
+
+#ifdef RT_USING_DEVICE_OPS
+    device->ops = &usbd_serial_ops;
+#else
+    device->init = NULL;
+    device->open = usbd_serial_open;
+    device->close = NULL;
+    device->read = usbd_serial_read;
+    device->write = usbd_serial_write;
+    device->control = NULL;
+#endif
+    device->user_data = data;
+
+    /* register a character device */
+    ret = rt_device_register(device, serial->name, RT_DEVICE_FLAG_RDWR | RT_DEVICE_FLAG_REMOVABLE);
+
+#ifdef RT_USING_POSIX_DEVIO
+    /* set fops */
+    device->fops = NULL;
+#endif
+    rt_ringbuffer_init(&serial->rx_rb, serial->rx_rb_buffer, sizeof(serial->rx_rb_buffer));
+
+    return ret;
+}
+
+void usbd_cdc_acm_bulk_out(uint8_t busid, uint8_t ep, uint32_t nbytes)
+{
+    struct usbd_serial *serial;
+
+    for (uint8_t devno = 0; devno < CONFIG_USBDEV_MAX_CDC_ACM_CLASS; devno++) {
+        serial = &g_usbd_serial_cdc_acm[devno];
+        if (serial->out_ep == ep) {
+            rt_ringbuffer_put(&serial->rx_rb, g_usbd_serial_cdc_acm_rx_buf[serial->minor], nbytes);
+            break;
+        }
+    }
+}
+
+void usbd_cdc_acm_bulk_in(uint8_t busid, uint8_t ep, uint32_t nbytes)
+{
+    struct usbd_serial *serial;
+
+    if ((nbytes % usbd_get_ep_mps(busid, ep)) == 0 && nbytes) {
+        /* send zlp */
+        usbd_ep_start_write(busid, ep, NULL, 0);
+    } else {
+        for (uint8_t devno = 0; devno < CONFIG_USBDEV_MAX_CDC_ACM_CLASS; devno++) {
+            serial = &g_usbd_serial_cdc_acm[devno];
+            if ((serial->in_ep == ep) && serial->tx_done) {
+                usb_osal_sem_give(serial->tx_done);
+                break;
+            }
+        }
+    }
+}
+
+void usbd_cdc_acm_serial_init(uint8_t busid, uint8_t in_ep, uint8_t out_ep)
+{
+    struct usbd_serial *serial;
+
+    struct usbd_endpoint cdc_out_ep = {
+        .ep_addr = out_ep,
+        .ep_cb = usbd_cdc_acm_bulk_out
+    };
+
+    struct usbd_endpoint cdc_in_ep = {
+        .ep_addr = in_ep,
+        .ep_cb = usbd_cdc_acm_bulk_in
+    };
+
+    serial = usbd_serial_alloc();
+    if (serial == NULL) {
+        USB_LOG_ERR("No more serial device available\n");
+        return;
+    }
+
+    serial->busid = busid;
+    serial->in_ep = in_ep;
+    serial->out_ep = out_ep;
+    serial->tx_done = usb_osal_sem_create(0);
+
+    usbd_add_interface(busid, usbd_cdc_acm_init_intf(busid, &serial->intf_ctrl));
+    usbd_add_interface(busid, usbd_cdc_acm_init_intf(busid, &serial->intf_data));
+    usbd_add_endpoint(busid, &cdc_out_ep);
+    usbd_add_endpoint(busid, &cdc_in_ep);
+
+    if (usbd_serial_register(serial, NULL) != RT_EOK) {
+        USB_LOG_ERR("Failed to register serial device\n");
+        usbd_serial_free(serial);
+        return;
+    }
+
+    USB_LOG_INFO("USB CDC ACM Serial Device %s initialized\n", serial->name);
+}
\ No newline at end of file