Commit 35725347 authored Mar 29, 2019 by Sriharsha Allenki

xhci: Fix possible interrupt storm with suspend failure



In the case where the xhci_suspend failed because the
controller is not halted within the delay, we see that
the xhc interrupts are not acked and is leading to
a storm of unwanted dwc3_interrupt calls.

Fix this by setting the HCD_FLAG_HW_ACCESSIBLE so that
the interrupts are acked by the xhci_irq.
Once the suspend failure happens, the device does not
respond to any new device connect/disconnect. So,
fix this by restarting the host stack by notifying the
hc_died to the dwc3 glue driver.

Change-Id: Ie383d5eacca428b123c1a071a304df54e087c42e
Signed-off-by: Sriharsha Allenki <sallenki@codeaurora.org>

parent 0fa82d7f

drivers/usb/host/xhci.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -985,6 +985,12 @@ int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup)
		if (xhci_handshake(&xhci->op_regs->status,
		STS_HALT, STS_HALT, delay)) {
		xhci_warn(xhci, "WARN: xHC CMD_RUN timeout\n");
		/* Set the HW_ACCESSIBLE so that any pending interrupts are
		* served.
		*/
		set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
		set_bit(HCD_FLAG_HW_ACCESSIBLE, &xhci->shared_hcd->flags);
		xhci_hc_died(xhci);
		spin_unlock_irq(&xhci->lock);
		return -ETIMEDOUT;
		}