On Thu, 3 Mar 2011, Mark Lord wrote: > Mmm.. I missed that part. Very curious, that. > I wonder if it could be some issue with how the interrupt controller is set up. > > Oh the other hand, this USB-GPS is probably a "full-speed" (slow) device, > using the UHCI interface rather than EHCI. > > The uhci_irq() handler (in uhci-hcd.c) appears to always return IRQ_HANDLED, > even when it didn't actually handle an IRQ. If I'm reading the code correctly, > then that's a bug, and could cause this issue given the "right" peripheral > (eg. your USB-GPS). > > I wonder if uhci_irq() can be a bit more clever and only set IRQ_HANDLED > for interrupts that it actually had to handle? Or am I reading it wrong? Evidently you didn't see these lines near the start of the routine: status = inw(uhci->io_addr + USBSTS); if (!(status & ~USBSTS_HCH)) /* shared interrupt, not mine */ return IRQ_NONE; 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
