Remove wrongly applied upper limit on the interrupt transfer interval for the low speed devices (not much of an error per se, according to the USB specs)...
Signed-off-by: Sergei Shtylyov <[email protected]> --- The patch is against the recent Linus' kernel. drivers/usb/musb/musb_host.c | 18 ++++++++++-------- 1 files changed, 10 insertions(+), 8 deletions(-) Index: linux-2.6/drivers/usb/musb/musb_host.c =================================================================== --- linux-2.6.orig/drivers/usb/musb/musb_host.c +++ linux-2.6/drivers/usb/musb/musb_host.c @@ -1857,19 +1857,21 @@ 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 _______________________________________________ Davinci-linux-open-source mailing list [email protected] http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
