tree 28ebdec53e33efce94b8a3d6be1f804e5d43a3d3
parent 8dec92b24064f1ffbb6537ba97729b633b400c28
author Sergei Shtylyov <sshtylyov@ru.mvista.com> 1309979978 +0400
committer Greg Kroah-Hartman <gregkh@suse.de> 1310162147 -0700

EHCI: only power off port if over-current is active

MAX4967 USB power supply chip we use on our boards signals over-current when
power is not enabled; once it's enabled, over-current signal returns to normal.
That unfortunately caused the endless stream of "over-current change on port"
messages. The EHCI root hub code reacts on every over-current signal change
with powering off the port -- such change event is generated the moment the
port power is enabled, so once enabled the power is immediately cut off.
I think we should only cut off power when we're seeing the active over-current
signal, so I'm adding such check to that code. I also think that the fact that
we've cut off the port power should be reflected in the result of GetPortStatus
request immediately, hence I'm adding a PORTSCn register readback after write...

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: stable@kernel.org
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>