On 11-03-03 03:11 PM, Alan Stern wrote: > On Thu, 3 Mar 2011, Mark Lord wrote: > >> Okay, dug out a UHCI 1.1 spec, and the indication from there >> is that uhci_irq() can return IRQ_HANDLED in some cases where IRQ_NONE >> is more appropriate. > > What cases are those? > >> Also, it is not masking the "Reserved" bits from the status register. >> Presumably most implementations "read zero" for those bits, >> but perhaps not all do. > > Perhaps not, but I've never come across one that does. This > essentially amounts to saying that the only reasons a UHCI controller > generates an interrupt request are the documented ones. > > Suppose the driver did mask out the reserved bits and return IRQ_NONE > when none of the defined bits were set. An implementation that did set > one of the reserved bits would then create an interrupt storm. You mean, like, the "error -71" storms that I *still* get from time to time, ever since the early 2.6.2x kernels? Yeah, perhaps. Cheers -- 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
