diff --git a/include/dev/usbc.h b/include/dev/usbc.h
index 26c1945..f566190 100644
--- a/include/dev/usbc.h
+++ b/include/dev/usbc.h
@@ -23,8 +23,76 @@
 #ifndef __DEV_USBC_H
 #define __DEV_USBC_H
 
-/* device side usb controller api (used by the usb stack) */
+#include <sys/types.h>
+#include <debug.h>
+#include <hw/usb.h>
+
 void usbc_init(void);
 
+typedef uint ep_t;
+
+typedef enum {
+	IN = 0,
+	OUT
+} ep_dir_t;
+
+typedef enum {
+	CB_RESET,
+	CB_SUSPEND,
+	CB_RESUME,
+	CB_DISCONNECT,
+	CB_ONLINE,
+	CB_OFFLINE,
+	CB_SETUP_MSG,
+	
+	/* endpoint transfer stuff */
+	CB_EP_RXCOMPLETE,
+	CB_EP_TXCOMPLETE,
+	CB_EP_TRANSFER_CANCELLED,
+} usbc_callback_op_t;
+
+typedef struct {
+	void *buf;
+	size_t buflen;
+	uint bufpos;
+	int result;
+	void *extra; // extra pointer to store whatever you want
+} usbc_transfer;
+
+enum {
+	USB_TRANSFER_RESULT_OK = 0,
+	USB_TRANSFER_RESULT_ERR = -1,
+	USB_TRANSFER_RESULT_CANCELLED = -2,
+};
+
+typedef int (*ep_callback)(ep_t endpoint, usbc_callback_op_t op, usbc_transfer *transfer);
+
+void usbc_setup_endpoint(ep_t ep, ep_dir_t dir, bool active, ep_callback callback, uint width, uint blocksize);
+int usbc_queue_rx(ep_t ep, usbc_transfer *transfer);
+int usbc_queue_tx(ep_t ep, usbc_transfer *transfer);
+
+/* setup arg is valid during CB_SETUP_MSG */
+union usb_callback_args {
+	const struct usb_setup *setup;
+};
+
+typedef int (*usb_callback)(usbc_callback_op_t op, const union usb_callback_args *args);
+
+int usbc_set_callback(usb_callback);
+int usbc_set_active(bool active);
+
+/* called back from within a callback to handle setup responses */
+void usbc_ep0_ack(void);
+void usbc_ep0_stall(void);
+void usbc_ep0_send(const void *buf, size_t len, size_t maxlen);
+void usbc_ep0_recv(void *buf, size_t len, ep_callback);
+
+bool usbc_is_highspeed(void);
+
+static inline void usbc_dump_transfer(const usbc_transfer *t)
+{
+	printf("usb transfer %p: buf %p, buflen %zd, bufpos %u, result %d\n", t, t->buf, t->buflen, t->bufpos, t->result);
+}
+
 #endif