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usb: ohci: disable start-of-frame interrupt in ohci_rh_suspend

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While going into S3 or S4 suspend, an OHCI host controller can
generate interrupt requests if the INTR_SF enable flag is set.  The
interrupt handler routine isn't prepared for this and it doesn't turn
off the flag, causing an interrupt storm.

To fix this problem, make ohci_rh_suspend() always disable INTR_SF
interrupts after processing the done list and the ED unlinks but
before the controller goes into the suspended (non-UsbOperational)
state.  There's no reason to leave the flag enabled, since a
suspended controller doesn't generate Start-of-Frame packets.

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Yinbo Zhu <zhuyinbo@loongson.cn>
Link: https://lore.kernel.org/r/1634095928-29639-1-git-send-email-zhuyinbo@loongson.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Yinbo Zhu 2021-10-13 11:32:08 +08:00 committed by Greg Kroah-Hartman
parent 6a47856145
commit 20f588ac98
1 changed files with 3 additions and 0 deletions
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3
drivers/usb/host/ohci-hub.c
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@ -91,6 +91,9 @@ __acquires(ohci->lock)
update_done_list(ohci); update_done_list(ohci);
ohci_work(ohci); ohci_work(ohci);
/* All ED unlinks should be finished, no need for SOF interrupts */
ohci_writel(ohci, OHCI_INTR_SF, &ohci->regs->intrdisable);
/* /*
* Some controllers don't handle "global" suspend properly if * Some controllers don't handle "global" suspend properly if
* there are unsuspended ports. For these controllers, put all * there are unsuspended ports. For these controllers, put all