> From: Sebastian Andrzej Siewior [mailto:bigeasy@xxxxxxxxxxxxx] > Sent: Tuesday, November 25, 2014 9:22 AM > > The max packet size within the FS descriptor has to be highest possible > value and _not_ the one that is (or will be) used on FS. > The way the code works (since day 1) is that usb_ep_autoconfig() is > invoked _only_ on the FS endpoint and then the endpoint address is > copies over to HS/SS endpoints. If the any of the "critical" options are > different between FS and HS then we have to pass the HS value and > correct later. > > What now happens is that we look for an INT-OUT endpoint of 64bytes. The > code will return an endpoint matching this category. Further the > sourcesink will take this endpoint and increase the MPS to 1024. On > net2280 for instance the code tries to be clever to return an endpoint > which can only do 64 MPS. The same happens on musb where we mostlike get > an endpoint which can only do 512. The result is then on the host side: > > |~# testusb -a -t 9 -c 2 > |unknown speed /dev/bus/usb/002/045 0 > |usbtest 2-1:3.0: TEST 9: ch9 (subset) control tests, 2 times > |usbtest 2-1:3.0: can't set_interface = 2, -32 > |usbtest 2-1:3.0: ch9 subset failed, iterations left 1 > |/dev/bus/usb/002/045 test 9 --> 32 (Broken pipe) > > because the on the gadget side we can't enable the endpoint because > desc->size > ep->max_size. > > Fixes: ef11982dd7a6 ("usb: gadget: zero: Add support for interrupt EP") > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> > --- > drivers/usb/gadget/function/f_sourcesink.c | 24 ++++++++++++------------ > 1 file changed, 12 insertions(+), 12 deletions(-) > > diff --git a/drivers/usb/gadget/function/f_sourcesink.c b/drivers/usb/gadget/function/f_sourcesink.c > index 80be25b32cd7..7d8f0216e1a6 100644 > --- a/drivers/usb/gadget/function/f_sourcesink.c > +++ b/drivers/usb/gadget/function/f_sourcesink.c > @@ -161,7 +161,7 @@ static struct usb_endpoint_descriptor fs_int_source_desc = { > > .bEndpointAddress = USB_DIR_IN, > .bmAttributes = USB_ENDPOINT_XFER_INT, > - .wMaxPacketSize = cpu_to_le16(64), > + .wMaxPacketSize = cpu_to_le16(1024), This seems strange. You are setting the max packet size in the FS Intr endpoint descriptor to a value that is illegal for FS. Won't that cause usb_ep_autoconfig() to fail if the UDC only has a FS Intr endpoint? Maybe you should set wMaxPacketSize to 0 instead? The ep_matches() function in epautoconf.c has this code: /* * If the protocol driver hasn't yet decided on wMaxPacketSize * and wants to know the maximum possible, provide the info. */ if (desc->wMaxPacketSize == 0) desc->wMaxPacketSize = cpu_to_le16(ep->maxpacket_limit); -- Paul -- 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
