/* Defaults to EP0 for now */
__noinline
static int
usb_tx_next(struct usbd_ep_pipe_state_t *s)
{
/**
* Us being here means the previous transfer just completed
* successfully. That means the host just toggled its data
* sync bit, and so do we.
*/
s->data01 ^= 1;
if (s->transfer_size > 0) {
size_t thislen = s->transfer_size;
if (thislen > s->ep_maxsize)
thislen = s->ep_maxsize;
else if (thislen != s->ep_maxsize)
s->short_transfer = 0;
void *addr = s->data_buf + s->pos;
if (s->copy_source) {
/* Bounce buffer mode */
addr = s->data_buf;
memcpy(addr, s->copy_source + s->pos, thislen);
}
s->pos += thislen;
s->transfer_size -= thislen;
usb_queue_next(s, addr, thislen);
s->pingpong ^= 1;
return (1);
}
/**
* All data has been shipped. Do we need to send a short
* packet?
*/
if (s->short_transfer) {
s->short_transfer = 0;
usb_queue_next(s, NULL, 0);
s->pingpong ^= 1;
return (1);
}
if (s->callback)
s->callback(s->data_buf, s->pos, s->callback_data);
return (0);
}
/**
* Receive USB data (OUT device transaction)
*
* Returns: size to be received, or -1 on error.
*/
int
usb_rx(struct usbd_ep_pipe_state_t *s, void *buf, size_t len, ep_callback_t cb, void *cb_data)
{
s->data_buf = buf;
s->transfer_size = len;
s->pos = 0;
s->callback = cb;
s->callback_data = cb_data;
size_t thislen = s->transfer_size;
if (thislen > s->ep_maxsize)
thislen = s->ep_maxsize;
usb_queue_next(s, s->data_buf, thislen);
return (len);
}
/* XXX pass usb_stat to validate pingpong */
__noinline
static int
usb_rx_next(struct usbd_ep_pipe_state_t *s)
{
/**
* Us being here means the previous transfer just completed
* successfully. That means the host just toggled its data
* sync bit, and so do we.
*/
s->data01 ^= 1;
size_t thislen = usb_ep_get_transfer_size(s);
s->transfer_size -= thislen;
s->pos += thislen;
/**
* We're done with this buffer now. Switch the pingpong now
* before we might have to receive the next piece of data.
*/
s->pingpong ^= 1;
/**
* If this is a short transfer, or we received what we
* expected, we're done.
*/
if (thislen < s->ep_maxsize || s->transfer_size == 0) {
if (s->callback)
s->callback(s->data_buf, s->pos, s->callback_data);
return (0);
}
/**
* Otherwise we still need to receive more data.
*/
size_t nextlen = s->transfer_size;
if (nextlen > s->ep_maxsize)
nextlen = s->ep_maxsize;
void *addr = s->data_buf + s->pos;
usb_queue_next(s, addr, nextlen);
return (1);
}