Hi Alan On Wed, Jul 25, 2012 at 9:07 PM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > On Wed, 25 Jul 2012, Rajaram R wrote: > >> Hi >> >> On Wed, Jul 25, 2012 at 6:33 PM, Michal Nazarewicz <mina86@xxxxxxxxxx> wrote: >> > On Wed, 25 Jul 2012 14:53:00 +0200, Rajaram REGUPATHY >> > <ragupathy.rajaram@xxxxxxxxxxxxxx> wrote: >> >> >> >> The short_not_ok field is used by class drivers to indicate udc whether >> >> short packet is expected during a particular transfer. >> >> In case of mass storage, during command and status phase this field is set >> >> as false and set to true during data phase. >> >> musb driver uses this field to decide whether to program DMA for mode1. >> >> This code is essential for musb driver to program DMA. >> > >> > >> > There's one thing I don't get. The message talks about musb but the code >> > checks for non Super Speed devices. So maybe the code is correct, maybe >> > it's not, but the message does not really explain it (at least to me). >> > >> Please let me know if this thread sets the context ? >> >> http://www.spinics.net/lists/linux-usb/msg64938.html > > I don't understand this either. What's wrong with setting short_not_ok > while at SuperSpeed? It shouldn't force the use of a bounce buffer. > I have just brought back some code removed by patch "usb: fix mass storage gadgets to work with Synopsys UDC". > In any case, the patch description should be improved to explain more > clearly what the real problem is. It should also be more clear about Sure. Will update the description > what the existing code does and what changes the patch makes; your > description above seems to say that the existing code sets short_not_ok > during the data phase. > > Alan Stern > -- 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
