On Sat, 19 Dec 2009, David Brownell wrote: > On Friday 18 December 2009, Alan Stern wrote: > > It's kind of awkward since the code > > in usb_set_device_state uses the ATT_WAKEUP bit in bmAttributes to > > determine whether a device is wakeup-capable, whereas rh_call_control > > in hcd.c uses the device's wakeup-capable bit to determine whether to > > set ATT_WAKEUP in bmAttributes. In other words, the flow of > > information is backward for root hubs as compared with other devices. > > The flow of information is consistently from device to core; > what you're observing is just a quirk of how ATT_WAKEUP gets > set to a nonzero value. :) That's true. IMO it would be less confusing if rh_call_control used a bit in the hcd structure to determine the setting of ATT_WAKEUP and then the core used ATT_WAKEUP to determine whether the root hub is wakeup-capable, just like it does with other USB devices. 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
