On Fri, 2013-01-11 at 11:06 +0800, Ming Lei wrote: > On Sat, Jan 5, 2013 at 9:26 AM, Dan Williams <d...@redhat.com> wrote: > > On Fri, 2013-01-04 at 23:16 +0100, Oliver Neukum wrote: > >> On Friday 04 January 2013 10:48:16 Dan Williams wrote: > >> > Some drivers (ex sierra_net) need the status interrupt URB > >> > active even when the device is closed, because they receive > >> > custom indications from firmware. Allow sub-drivers to set > >> > a flag that submits the status interrupt URB on probe and > >> > keeps the URB alive over device open/close. The URB is still > >> > killed/re-submitted for suspend/resume, as before. > >> > > >> > Signed-off-by: Dan Williams <d...@redhat.com> > >> > --- > >> > Oliver: alternatively, is there a problem with *always* > >> > submitting the interrupt URB, and then simply not calling > >> > the subdriver's .status function when the netdev is > >> > closed? That would be a much simpler patch. > >> > >> That is quite radical. We have no idea what a device > >> does when we do not react to a status update. I would > >> much prefer to not take the risk. > >> Besides, we don't use bandwidth if we don't have to. > > > > Ok, so scratch the alternative. Thus, does the posted patch look like > > the right course of action? > > > > If I wasn't clear enough before, sierra_net needs to listen to the > > status interrupt URB to receive the custom Restart indication as part of > > the driver's device setup. Thus for sierra_net at least, tying the > > I am curious who are interested in the 'custom Restart indication' > information after the interface is closed.
It's actually before the interface is even opened. It's really just a sync signal that's part of the driver's setup/initialization of the device. > If sierra_net provides ways(such as read registers) to query the > indication event, you can just query the information and setup > the device in driver_info->reset() during device open, so you can > avoid submitting interrupt URB always. As far as I know, it does not, or at least Sierra hasn't released such information about the firmware API of their devices. Dan > > status interrupt URB submission to device open/close isn't right. > > In theory, drivers should support to report its link status > even it is closed, but looks no much actual usage, so guys opt to > submit the interrupt URB only after it is opened. > > > Thanks, > -- > Ming Lei > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
