[PATCH AUTOSEL 5.4 10/46] xhci: bail out early if driver can't accress host in resume

[Sasha Levin <sashal@kernel.org>]

From: Mathias Nyman <mathias.nyman@linux.intel.com>

[ Upstream commit 72ae194704da212e2ec312ab182a96799d070755 ]

Bail out early if the xHC host needs to be reset at resume
but driver can't access xHC PCI registers.

If xhci driver already fails to reset the controller then there
is no point in attempting to free, re-initialize, re-allocate and
re-start the host. If failure to access the host is detected later,
failing the resume, xhci interrupts will be double freed
when remove is called.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20200312144517.1593-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/host/xhci.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 9b3b1b16eafba..2f49a7b3ce854 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1157,8 +1157,10 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
 		xhci_dbg(xhci, "Stop HCD\n");
 		xhci_halt(xhci);
 		xhci_zero_64b_regs(xhci);
-		xhci_reset(xhci);
+		retval = xhci_reset(xhci);
 		spin_unlock_irq(&xhci->lock);
+		if (retval)
+			return retval;
 		xhci_cleanup_msix(xhci);
 
 		xhci_dbg(xhci, "// Disabling event ring interrupts\n");
-- 
2.20.1