Re: [RFC PATCH] USB: enable "power/wakeup" to control remote wakeup in the runtime suspend

[Oliver Neukum <oneukum@xxxxxxx>]

On Tuesday 17 July 2012 14:52:51 Sarah Sharp wrote:
> 2. If an internal USB port is suspended with remote wakeup disabled,
> power off the port.  Add code to the USB core to ignore the device
> disconnect in this special case, so the driver thinks the device is
> still suspended.  Issue a reset-resume when the driver wants to resume
> the device.
> 
> That policy would be safe, because for 1) we would never see a USB
> device connection, and thus wouldn't miss the connection when we powered
> off the port.  2) is safe because we won't miss a remote wakeup while
> the port is powered off, and the device can't be disconnected by the
> user because it's an internal USB device.

That is still problematic. Because it depends on the driver and the core
being able to reinit a device from a cold start. For devices that take
a firmware this is untrue. Unfortunately internal BT and 3G devices are
the most prominent examples of devices needing firmware.

	Regards
		Oliver

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