On Thu, Nov 03, 2016 at 11:27:40AM +0200, Felipe Balbi wrote: > > Hi, > > Peter Chen <[email protected]> writes: > >> Peter Chen <[email protected]> writes: > >> > For isoc endpoint descriptor, the wMaxPacketSize is not real max packet > >> > size (see Table 9-13. Standard Endpoint Descriptor, USB 2.0 > >> > specifcation), > >> > it may contain the number of packet, so the real max packet should be > >> > ep->desc->wMaxPacketSize && 0x7ff. > >> > > >> > Cc: Felipe F. Tonello <[email protected]> > >> > Cc: Felipe Balbi <[email protected]> > >> > Fixes: 16b114a6d797 ("usb: gadget: fix usb_ep_align_maybe > >> > endianness and new usb_ep_aligna") > >> > > >> > Signed-off-by: Peter Chen <[email protected]> > >> > --- > >> > include/linux/usb/gadget.h | 5 ++++- > >> > 1 file changed, 4 insertions(+), 1 deletion(-) > >> > > >> > diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h > >> > index 8e81f9e..cce2db6 100644 > >> > --- a/include/linux/usb/gadget.h > >> > +++ b/include/linux/usb/gadget.h > >> > @@ -429,7 +429,10 @@ static inline struct usb_gadget > >> > *dev_to_usb_gadget(struct device *dev) > >> > */ > >> > static inline size_t usb_ep_align(struct usb_ep *ep, size_t len) > >> > { > >> > - return round_up(len, > >> > (size_t)le16_to_cpu(ep->desc->wMaxPacketSize)); > >> > + int max_packet_size = > >> > (size_t)le16_to_cpu(ep->desc->wMaxPacketSize) > >> > + && 0x7ff; > ^^ > hehe, I just noticed this bug. Did you really test this patch? :-) >
Any problems you find? Without this patch, the usbtest can't be ran for high bandwidth isoc transfer. > >> > + > >> > + return round_up(len, max_packet_size); > >> > } > >> > >> care to update this to use new usb_endpoint_maxp()? > >> > > > > But it is a bug existed at v4.9, the usb_ep_align returns wrong request > > length for isoc. I found this bug by running usbtest. > > keep your & (after fixing it), but use usb_endpoint_maxp(). Later we can > just remove the unnecessary & operation. > > -- > balbi I will use usb_endpoint_maxp, but I still not find the problem for this patch. -- Best Regards, Peter Chen -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
