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. 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 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
