Messages in this thread | | | Date | Tue, 7 Jan 2014 07:25:13 -0800 | From | Greg KH <> | Subject | Re: [PATCH] usb:hub set hub->change_bits when over-current happens |
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On Tue, Jan 07, 2014 at 02:38:36PM +0800, Shen Guang wrote: > On Tue, Jan 7, 2014 at 11:53 AM, Greg KH <gregkh@linuxfoundation.org> wrote: > > On Tue, Jan 07, 2014 at 11:35:50AM +0800, 沈光 wrote: > >> On Tue, Jan 7, 2014 at 10:40 AM, Greg KH <gregkh@linuxfoundation.org> wrote: > >> > On Tue, Jan 07, 2014 at 10:33:14AM +0800, 沈光 wrote: > >> >> set hub->change_bits when we plug in a device which causes > >> >> over-current condition, so that hub_events() will check it. > >> > > >> > Why? > >> > > >> > What does this solve? Is this a bug with existing devices that needs to > >> > be backported to older kernels? > >> > > >> > thanks, > >> > > >> > greg k-h > >> > >> This is something that we found when we are doing compliance test with xHCI. > >> If we enable CONFIG_USB_SUSPEND, and plug in a bad device which causes > >> over-current condition to the root port, the hub->change_bits will not > >> be set in current code in the function of hub_activate. > > > > Now that's something that should go in the changelog, don't you think? > > > > thanks, > > > > greg k-h > > Sure, I agree. > I am sorry I didn't make it clear enough. > And the reason why over-current can be detected if CONFIG_USB_SUSPEND > is disabled, is that the interrupt pipe of the hub will report the > change and set hub->event_bits, and then hub_events() will check what > events happened.
Great, care to resend the patch with all of this information added to it?
thanks,
greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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