4.14-stable review patch. If anyone has any objections, please let me know.
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From: Kai Heng Feng kai.heng.feng@canonical.com
commit 8feaec33b9868582654cd3d5355225dcb79aeca6 upstream.
USB controller ASM1042 stops working after commit de3ef1eb1cd0 (PM / core: Drop run_wake flag from struct dev_pm_info).
The device in question is not power managed by platform firmware, furthermore, it only supports PME# from D3cold: Capabilities: [78] Power Management version 3 Flags: PMEClk- DSI- D1- D2- AuxCurrent=55mA PME(D0-,D1-,D2-,D3hot-,D3cold+) Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
Before commit de3ef1eb1cd0, the device never gets runtime suspended. After that commit, the device gets runtime suspended to D3hot, which can not generate any PME#.
usb_hcd_pci_probe() unconditionally calls device_wakeup_enable(), hence device_can_wakeup() in pci_dev_run_wake() always returns true.
So pci_dev_run_wake() needs to check PME wakeup capability as its first condition.
In addition, change wakeup flag passed to pci_target_state() from false to true, because we want to find the deepest state different from D3cold that the device can still generate PME#. In this case, it's D0 for the device in question.
Fixes: de3ef1eb1cd0 (PM / core: Drop run_wake flag from struct dev_pm_info) Signed-off-by: Kai-Heng Feng kai.heng.feng@canonical.com Cc: 4.13+ stable@vger.kernel.org # 4.13+ Acked-by: Bjorn Helgaas bhelgaas@google.com Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/pci/pci.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -2120,16 +2120,16 @@ bool pci_dev_run_wake(struct pci_dev *de { struct pci_bus *bus = dev->bus;
- if (device_can_wakeup(&dev->dev)) - return true; - if (!dev->pme_support) return false;
/* PME-capable in principle, but not from the target power state */ - if (!pci_pme_capable(dev, pci_target_state(dev, false))) + if (!pci_pme_capable(dev, pci_target_state(dev, true))) return false;
+ if (device_can_wakeup(&dev->dev)) + return true; + while (bus->parent) { struct pci_dev *bridge = bus->self;