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Alan Stern authored
Some OHCI controllers from ATI/AMD seem to have difficulty with "global" USB suspend, that is, suspending an entire USB bus without setting the suspend feature for each port connected to a device. When we try to resume the child devices, the controller gives timeout errors on the unsuspended ports, requiring resets, and can even cause ohci-hcd to hang; see http://marc.info/?l=linux-usb&m=139514332820398&w=2 and the following messages. This patch fixes the problem by adding a new quirk flag to ohci-hcd. The flag causes the ohci_rh_suspend() routine to suspend each unsuspended, enabled port before suspending the root hub. This effectively converts the "global" suspend to an ordinary root-hub suspend. There is no need to unsuspend these ports when the root hub is resumed, because the child devices will be resumed anyway in the course of a normal system resume ("global" suspend is never used for runtime PM). This patch should be applied to all stable kernels which include commit 0aa2832d (USB: use "global suspend" for system sleep on USB-2 buses) or a backported version thereof. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Peter Münster <pmlists@free.fr> Tested-by: Peter Münster <pmlists@free.fr> CC: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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