OHCI: final fix for NVIDIA problems (I hope)
commit8dccddbc2368cd64e33a6051f800aec35909aed3
authorAlan Stern <stern@rowland.harvard.edu>
Thu, 17 Nov 2011 21:41:45 +0000 (17 16:41 -0500)
committerGreg Kroah-Hartman <gregkh@suse.de>
Thu, 12 Jan 2012 19:33:40 +0000 (12 11:33 -0800)
tree7dcda40a8de733cf481b92563ab703220d7c697d
parent190c026b867605e51f5e24a9c32a8463ada12830
OHCI: final fix for NVIDIA problems (I hope)

commit c61875977458637226ab093a35d200f2d5789787 upstream.

Problems with NVIDIA's OHCI host controllers persist.  After looking
carefully through the spec, I finally realized that when a controller
is reset it then automatically goes into a SUSPEND state in which it
is completely quiescent (no DMA and no IRQs) and from which it will
not awaken until the system puts it into the OPERATIONAL state.

Therefore there's no need to worry about controllers being in the
RESET state for extended periods, or remaining in the OPERATIONAL
state during system shutdown.  The proper action for device
initialization is to put the controller into the RESET state (if it's
not there already) and then to issue a software reset.  Similarly, the
proper action for device shutdown is simply to do a software reset.

This patch (as1499) implements such an approach.  It simplifies
initialization and shutdown, and allows the NVIDIA shutdown-quirk code
to be removed.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Andre "Osku" Schmidt <andre.osku.schmidt@googlemail.com>
Tested-by: Arno Augustin <Arno.Augustin@web.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/usb/host/ohci-hcd.c
drivers/usb/host/ohci-pci.c
drivers/usb/host/ohci.h
drivers/usb/host/pci-quirks.c