1 files changed, 154 insertions, 0 deletions
diff --git a/app/cdc.c b/app/cdc.c
new file mode 100644
index 0000000..4088b6c
--- /dev/null
+++ b/app/cdc.c
@@ -0,0 +1,154 @@
+#include "project.h"
+
+static const struct usb_endpoint_descriptor comm_endp[] = {
+  {
+    .bLength = USB_DT_ENDPOINT_SIZE,
+    .bDescriptorType = USB_DT_ENDPOINT,
+    .bEndpointAddress = 0x83,
+    .bmAttributes = USB_ENDPOINT_ATTR_INTERRUPT,
+    .wMaxPacketSize = 16,
+    .bInterval = 255,
+  }
+};
+
+static const struct usb_endpoint_descriptor data_endp[] = {
+  {
+    .bLength = USB_DT_ENDPOINT_SIZE,
+    .bDescriptorType = USB_DT_ENDPOINT,
+    .bEndpointAddress = 0x01,
+    .bmAttributes = USB_ENDPOINT_ATTR_BULK,
+    .wMaxPacketSize = 64,
+    .bInterval = 1,
+  },
+  {
+    .bLength = USB_DT_ENDPOINT_SIZE,
+    .bDescriptorType = USB_DT_ENDPOINT,
+    .bEndpointAddress = 0x82,
+    .bmAttributes = USB_ENDPOINT_ATTR_BULK,
+    .wMaxPacketSize = 64,
+    .bInterval = 1,
+  }
+};
+
+static const struct {
+  struct usb_cdc_header_descriptor header;
+  struct usb_cdc_call_management_descriptor call_mgmt;
+  struct usb_cdc_acm_descriptor acm;
+  struct usb_cdc_union_descriptor cdc_union;
+} __attribute__((packed)) cdcacm_functional_descriptors = {
+  .header = {
+    .bFunctionLength = sizeof(struct usb_cdc_header_descriptor),
+    .bDescriptorType = CS_INTERFACE,
+    .bDescriptorSubtype = USB_CDC_TYPE_HEADER,
+    .bcdCDC = 0x0110,
+  },
+  .call_mgmt = {
+    .bFunctionLength = 
+    sizeof(struct usb_cdc_call_management_descriptor),
+    .bDescriptorType = CS_INTERFACE,
+    .bDescriptorSubtype = USB_CDC_TYPE_CALL_MANAGEMENT,
+    .bmCapabilities = 0,
+    .bDataInterface = 1,
+  },
+  .acm = {
+    .bFunctionLength = sizeof(struct usb_cdc_acm_descriptor),
+    .bDescriptorType = CS_INTERFACE,
+    .bDescriptorSubtype = USB_CDC_TYPE_ACM,
+    .bmCapabilities = 0,
+  },
+  .cdc_union = {
+    .bFunctionLength = sizeof(struct usb_cdc_union_descriptor),
+    .bDescriptorType = CS_INTERFACE,
+    .bDescriptorSubtype = USB_CDC_TYPE_UNION,
+    .bControlInterface = 0,
+    .bSubordinateInterface0 = 1, 
+  }
+};
+
+const struct usb_interface_descriptor comm_iface[] = {
+  {
+    .bLength = USB_DT_INTERFACE_SIZE,
+    .bDescriptorType = USB_DT_INTERFACE,
+    .bInterfaceNumber = 0,
+    .bAlternateSetting = 0,
+    .bNumEndpoints = 1,
+    .bInterfaceClass = USB_CLASS_CDC,
+    .bInterfaceSubClass = USB_CDC_SUBCLASS_ACM,
+    .bInterfaceProtocol = USB_CDC_PROTOCOL_AT,
+    .iInterface = 0,
+    .endpoint = comm_endp,
+    .extra = &cdcacm_functional_descriptors,
+    .extralen = sizeof(cdcacm_functional_descriptors)
+  }
+};
+
+const struct usb_interface_descriptor data_iface[] = {
+  {
+    .bLength = USB_DT_INTERFACE_SIZE,
+    .bDescriptorType = USB_DT_INTERFACE,
+    .bInterfaceNumber = 1,
+    .bAlternateSetting = 0,
+    .bNumEndpoints = 2,
+    .bInterfaceClass = USB_CLASS_DATA,
+    .bInterfaceSubClass = 0,
+    .bInterfaceProtocol = 0,
+    .iInterface = 0,
+    .endpoint = data_endp,
+  }
+};
+
+
+int cdcacm_control_request(usbd_device *usbd_dev,
+				  struct usb_setup_data *req,
+				  uint8_t **buf,
+				  uint16_t *len,
+				  int (**complete)(usbd_device *usbd_dev,
+						    struct usb_setup_data *req))
+{
+  (void)complete;
+  (void)buf;
+  (void)usbd_dev;
+
+  switch(req->bRequest) {
+  case USB_CDC_REQ_SET_CONTROL_LINE_STATE: {
+    /*
+     * This Linux cdc_acm driver requires this to be implemented
+     * even though it's optional in the CDC spec, and we don't
+     * advertise it in the ACM functional descriptor.
+     */
+    char local_buf[10];
+    struct usb_cdc_notification *notif = (void *)local_buf;
+
+    /* We echo signals back to host as notification. */
+    notif->bmRequestType = 0xA1;
+    notif->bNotification = USB_CDC_NOTIFY_SERIAL_STATE;
+    notif->wValue = 0;
+    notif->wIndex = 0;
+    notif->wLength = 2;
+    local_buf[8] = req->wValue & 3;
+    local_buf[9] = 0;
+    // usbd_ep_write_packet(0x83, buf, 10);
+    return 1;
+  }
+  case USB_CDC_REQ_SET_LINE_CODING: 
+    if(*len < sizeof(struct usb_cdc_line_coding)) {
+      return 0;
+    }
+    return 1;
+  }
+  return 0;
+}
+
+void cdcacm_data_rx_cb(usbd_device *usbd_dev, uint8_t ep)
+{
+  (void)ep;
+  char buf[64];
+  int len = usbd_ep_read_packet(usbd_dev, 0x01, buf, 64);
+
+
+  if (len) {
+    buf[0]^=32;
+    usbd_ep_write_packet(usbd_dev, 0x82, buf, len);
+    buf[len] = 0;
+  }
+}