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-rw-r--r--drivers/usb/host/xhci-mem.c32
1 files changed, 24 insertions, 8 deletions
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index ffeee575fd21..64fbf6f26f93 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1002,26 +1002,42 @@ static unsigned int xhci_parse_exponent_interval(struct usb_device *udev,
}
/*
- * Convert bInterval expressed in frames (in 1-255 range) to exponent of
+ * Convert bInterval expressed in microframes (in 1-255 range) to exponent of
* microframes, rounded down to nearest power of 2.
*/
-static unsigned int xhci_parse_frame_interval(struct usb_device *udev,
- struct usb_host_endpoint *ep)
+static unsigned int xhci_microframes_to_exponent(struct usb_device *udev,
+ struct usb_host_endpoint *ep, unsigned int desc_interval,
+ unsigned int min_exponent, unsigned int max_exponent)
{
unsigned int interval;
- interval = fls(8 * ep->desc.bInterval) - 1;
- interval = clamp_val(interval, 3, 10);
- if ((1 << interval) != 8 * ep->desc.bInterval)
+ interval = fls(desc_interval) - 1;
+ interval = clamp_val(interval, min_exponent, max_exponent);
+ if ((1 << interval) != desc_interval)
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);
+ desc_interval);
return interval;
}
+static unsigned int xhci_parse_microframe_interval(struct usb_device *udev,
+ struct usb_host_endpoint *ep)
+{
+ return xhci_microframes_to_exponent(udev, ep,
+ ep->desc.bInterval, 0, 15);
+}
+
+
+static unsigned int xhci_parse_frame_interval(struct usb_device *udev,
+ struct usb_host_endpoint *ep)
+{
+ return xhci_microframes_to_exponent(udev, ep,
+ ep->desc.bInterval * 8, 3, 10);
+}
+
/* Return the polling or NAK interval.
*
* The polling interval is expressed in "microframes". If xHCI's Interval field
@@ -1040,7 +1056,7 @@ static unsigned int xhci_get_endpoint_interval(struct usb_device *udev,
/* Max NAK rate */
if (usb_endpoint_xfer_control(&ep->desc) ||
usb_endpoint_xfer_bulk(&ep->desc)) {
- interval = ep->desc.bInterval;
+ interval = xhci_parse_microframe_interval(udev, ep);
break;
}
/* Fall through - SS and HS isoc/int have same decoding */