From 20f588ac9841edaf3e03fb24afe43ee530622a3c Mon Sep 17 00:00:00 2001 From: Yinbo Zhu Date: Wed, 13 Oct 2021 11:32:08 +0800 Subject: [PATCH] usb: ohci: disable start-of-frame interrupt in ohci_rh_suspend 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 Signed-off-by: Yinbo Zhu Link: https://lore.kernel.org/r/1634095928-29639-1-git-send-email-zhuyinbo@loongson.cn Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ohci-hub.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/usb/host/ohci-hub.c b/drivers/usb/host/ohci-hub.c index f474f2f9c1e4..90cee192e96d 100644 --- a/drivers/usb/host/ohci-hub.c +++ b/drivers/usb/host/ohci-hub.c @@ -91,6 +91,9 @@ __acquires(ohci->lock) update_done_list(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 * there are unsuspended ports. For these controllers, put all