From: Sergei Shtylyov <sshtylyov@xxxxxxxxxxxxx>
Remove wrongly applied upper limit on the interrupt transfer
interval for low speed devices (not much of an error per se,
according to USB specs).
Signed-off-by: Sergei Shtylyov <sshtylyov@xxxxxxxxxxxxx>
Signed-off-by: David Brownell <dbrownell@xxxxxxxxxxxxxxxxxxxxx>
---
BUGFIX: for 2.6.29-rc
drivers/usb/musb/musb_host.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)
--- a/drivers/usb/musb/musb_host.c
+++ b/drivers/usb/musb/musb_host.c
@@ -1863,19 +1863,21 @@ static int musb_urb_enqueue(
}
qh->type_reg = type_reg;
- /* precompute rxinterval/txinterval register */
- interval = min((u8)16, epd->bInterval); /* log encoding */
+ /* Precompute RXINTERVAL/TXINTERVAL register */
switch (qh->type) {
case USB_ENDPOINT_XFER_INT:
- /* fullspeed uses linear encoding */
- if (USB_SPEED_FULL == urb->dev->speed) {
- interval = epd->bInterval;
- if (!interval)
- interval = 1;
+ /*
+ * Full/low speeds use the linear encoding,
+ * high speed uses the logarithmic encoding.
+ */
+ if (urb->dev->speed <= USB_SPEED_FULL) {
+ interval = max_t(u8, epd->bInterval, 1);
+ break;
}
/* FALLTHROUGH */
case USB_ENDPOINT_XFER_ISOC:
- /* iso always uses log encoding */
+ /* ISO always uses logarithmic encoding */
+ interval = min_t(u8, epd->bInterval, 16);
break;
default:
/* REVISIT we actually want to use NAK limits, hinting to the
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
