OHCI: fix regression caused by nVidia shutdown workaround
This patch (as1463) fixes a regression caused by commit 3df7169e (OHCI: work around for nVidia shutdown problem). The original problem encountered by people using NVIDIA chipsets was that USB devices were not turning off when the system shut down. For example, the LED on an optical mouse would remain on, draining a laptop's battery. The problem was caused by a bug in the chipset; an OHCI controller in the Reset state would continue to drive a bus reset signal even after system shutdown. The workaround was to put the controllers into the Suspend state instead. It turns out that later NVIDIA chipsets do not suffer from this bug. Instead some have the opposite bug: If a system is shut down while an OHCI controller is in the Suspend state, USB devices remain powered! On other systems, shutting down with a Suspended controller causes the system to reboot immediately. Thus, working around the original bug on some machines exposes other bugs on other machines. The best solution seems to be to limit the workaround to OHCI controllers with a low-numbered PCI product ID. I don't know exactly at what point NVIDIA changed their chipsets; the value used here is a guess. So far it was worked out okay for all the people who have tested it. This fixes Bugzilla #35032. Signed-off-by: NAlan Stern <stern@rowland.harvard.edu> Tested-by: NAndre "Osku" Schmidt <andre.osku.schmidt@googlemail.com> Tested-by: NYury Siamashka <yurand2@gmail.com> CC: <stable@kernel.org> Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
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