On Tue, Sep 25, 2012 at 1:06 AM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > On Tue, 25 Sep 2012, Ming Lei wrote: > >> IMO, it should be reasonable to set the device's autosuspend delay >> as zero when its driver is unbound because no one can predict when >> the device will be bound to a new driver. > > It could be set to a low value, but it shouldn't be set to 0. There If so, I'd rather to keep the default 2 seconds. Changing it to zero can avoid one auto suspend timer which may increase CPU power usage. > aren't too many things you can do with an unbound device; lsusb is one > of the most common. Considered 'lsusb' is a low frequency tool for final users, so could we just ignore it for the case? > > On the other hand, we already have a usbcore module parameter for > specifying the default autosuspend delay. That's what the delay is set > to when a device is first initialized, before it is bound to anything. > Unfortunately the parameter's value is in seconds, not milliseconds, so > we can't set it to any positive value smaller than 1 second. It is a global and can't be used to just change on unbound device. Thanks, -- Ming Lei -- 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
