[PATCH 4.14 181/237] xhci: fix runtime pm enabling for quirky Intel hosts

Greg Kroah-Hartman
2020-02-27T14:33:53Z

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

commit 024d411e9c5d49eb96c825af52a3ce2682895676 upstream.

Intel hosts that need the XHCI_PME_STUCK_QUIRK flag should enable
runtime pm by calling xhci_pme_acpi_rtd3_enable() before
usb_hcd_pci_probe() calls pci_dev_run_wake().
Otherwise usage count for the device won't be decreased, and runtime
suspend is prevented.

usb_hcd_pci_probe() only decreases the usage count if device can
generate run-time wake-up events, i.e. when pci_dev_run_wake()
returns true.

This issue was exposed by pci_dev_run_wake() change in
commit 8feaec33b986 ("PCI / PM: Always check PME wakeup capability for
runtime wakeup support")
and should be backported to kernels with that change

Cc: <stable@vger.kernel.org> # 4.13+
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20200210134553.9144-4-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/usb/host/xhci-pci.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -284,6 +284,9 @@ static int xhci_pci_setup(struct usb_hcd
if (!usb_hcd_is_primary_hcd(hcd))
return 0;

+ if (xhci->quirks & XHCI_PME_STUCK_QUIRK)
+ xhci_pme_acpi_rtd3_enable(pdev);
+
xhci_dbg(xhci, "Got SBRN %u\n", (unsigned int) xhci->sbrn);

/* Find any debug ports */
@@ -344,9 +347,6 @@ static int xhci_pci_probe(struct pci_dev
HCC_MAX_PSA(xhci->hcc_params) >= 4)
xhci->shared_hcd->can_do_streams = 1;

- if (xhci->quirks & XHCI_PME_STUCK_QUIRK)
- xhci_pme_acpi_rtd3_enable(dev);
-
/* USB-2 and USB-3 roothubs initialized, allow runtime pm suspend */
pm_runtime_put_noidle(&dev->dev);