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Merge branch 'pm-pci' 

Merge a PCI power management regression fix.

* pm-pci:
  PCI / ACPI / PM: Resume bridges w/o drivers on suspend-to-RAM
hifive-unleashed-5.1
Rafael J. Wysocki 2018-07-05 12:47:16 +02:00
parent 895b66129a 26112ddc25
commit 88b96088e9
1 changed files with 12 additions and 0 deletions
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12
drivers/pci/pci-acpi.c
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@ -629,6 +629,18 @@ static bool acpi_pci_need_resume(struct pci_dev *dev)
{
struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
/*
* In some cases (eg. Samsung 305V4A) leaving a bridge in suspend over
* system-wide suspend/resume confuses the platform firmware, so avoid
* doing that, unless the bridge has a driver that should take care of
* the PM handling. According to Section 16.1.6 of ACPI 6.2, endpoint
* devices are expected to be in D3 before invoking the S3 entry path
* from the firmware, so they should not be affected by this issue.
*/
if (pci_is_bridge(dev) && !dev->driver &&
acpi_target_system_state() != ACPI_STATE_S0)
return true;
if (!adev || !acpi_device_power_manageable(adev))
return false;