/* Return the polling or NAK interval.
*
* The polling interval is expressed in "microframes". If xHCI's Interval field
* is set to N, it will service the endpoint every 2^(Interval)*125us.
*
* The NAK interval is one NAK per 1 to 255 microframes, or no NAKs if interval
* is set to 0.
*/
static inline unsigned int xhci_get_endpoint_interval(struct usb_device *udev,
struct usb_host_endpoint *ep)
{
unsigned int interval = 0;
switch (udev->speed) {
case USB_SPEED_HIGH:
/* Max NAK rate */
if (usb_endpoint_xfer_control(&ep->desc) ||
usb_endpoint_xfer_bulk(&ep->desc))
interval = ep->desc.bInterval;
/* Fall through - SS and HS isoc/int have same decoding */
case USB_SPEED_SUPER:
if (usb_endpoint_xfer_int(&ep->desc) ||
usb_endpoint_xfer_isoc(&ep->desc)) {
if (ep->desc.bInterval == 0)
interval = 0;
else
interval = ep->desc.bInterval - 1;
if (interval > 15)
interval = 15;
if (interval != ep->desc.bInterval + 1)
dev_warn(&udev->dev, "ep %#x - rounding interval to %d microframes\n",
ep->desc.bEndpointAddress, 1 << interval);
}
break;
/* Convert bInterval (in 1-255 frames) to microframes and round down to
* nearest power of 2.
*/
case USB_SPEED_FULL:
case USB_SPEED_LOW:
if (usb_endpoint_xfer_int(&ep->desc) ||
usb_endpoint_xfer_isoc(&ep->desc)) {
interval = fls(8*ep->desc.bInterval) - 1;
if (interval > 10)
interval = 10;
if (interval < 3)
interval = 3;
if ((1 << interval) != 8*ep->desc.bInterval)
dev_warn(&udev->dev,
"ep %#x - rounding interval"
" to %d microframes, "
"ep desc says %d microframes\n",
ep->desc.bEndpointAddress,
1 << interval,
8*ep->desc.bInterval);
}
break;
default:
BUG();
}
return EP_INTERVAL(interval);
}
/* Return the polling or NAK interval.
*
* The polling interval is expressed in "microframes". If xHCI's Interval field
* is set to N, it will service the endpoint every 2^(Interval)*125us.
*
* The NAK interval is one NAK per 1 to 255 microframes, or no NAKs if interval
* is set to 0.
*/
static inline unsigned int xhci_get_endpoint_interval(struct usb_device *udev,
struct usb_host_endpoint *ep)
{
unsigned int interval = 0;
switch (udev->speed) {
case USB_SPEED_HIGH:
/* Max NAK rate */
if (usb_endpoint_xfer_control(&ep->desc) ||
usb_endpoint_xfer_bulk(&ep->desc)) {
interval = xhci_parse_microframe_interval(udev, ep);
break;
}
/* Fall through - SS and HS isoc/int have same decoding */
case USB_SPEED_SUPER:
if (usb_endpoint_xfer_int(&ep->desc) ||
usb_endpoint_xfer_isoc(&ep->desc)) {
interval = xhci_parse_exponent_interval(udev, ep);
}
break;
case USB_SPEED_FULL:
if (usb_endpoint_xfer_isoc(&ep->desc)) {
interval = xhci_parse_exponent_interval(udev, ep);
break;
}
/*
* Fall through for interrupt endpoint interval decoding
* since it uses the same rules as low speed interrupt
* endpoints.
*/
case USB_SPEED_LOW:
if (usb_endpoint_xfer_int(&ep->desc) ||
usb_endpoint_xfer_isoc(&ep->desc)) {
interval = xhci_parse_frame_interval(udev, ep);
}
break;
default:
BUG();
}
return EP_INTERVAL(interval);
}
