PCI: PM/ACPI: Refresh all stale power state data in pci_pm_complete()

In pci_pm_complete() there are checks to decide whether or not to
resume devices that were left in runtime-suspend during the preceding
system-wide transition into a sleep state.  They involve checking the
current power state of the device and comparing it with the power
state of it set before the preceding system-wide transition, but the
platform component of the device's power state is not handled
correctly in there.

Namely, on platforms with ACPI, the device power state information
needs to be updated with care, so that the reference counters of
power resources used by the device (if any) are set to ensure that
the refreshed power state of it will be maintained going forward.

To that end, introduce a new ->refresh_state() platform PM callback
for PCI devices, for asking the platform to refresh the device power
state data and ensure that the corresponding power state will be
maintained going forward, make it invoke acpi_device_update_power()
(for devices with ACPI PM) on platforms with ACPI and make
pci_pm_complete() use it, through a new pci_refresh_power_state()
wrapper function.

Fixes: a0d2a959d3da (PCI: Avoid unnecessary resume after direct-complete)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index 2abe0eeafb53..45049f558860 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -692,6 +692,14 @@ static pci_power_t acpi_pci_get_power_state(struct pci_dev *dev)
 	return state_conv[state];
 }
 
+static void acpi_pci_refresh_power_state(struct pci_dev *dev)
+{
+	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
+
+	if (adev && acpi_device_power_manageable(adev))
+		acpi_device_update_power(adev, NULL);
+}
+
 static int acpi_pci_propagate_wakeup(struct pci_bus *bus, bool enable)
 {
 	while (bus->parent) {
@@ -749,6 +757,7 @@ static const struct pci_platform_pm_ops acpi_pci_platform_pm = {
 	.is_manageable = acpi_pci_power_manageable,
 	.set_state = acpi_pci_set_power_state,
 	.get_state = acpi_pci_get_power_state,
+	.refresh_state = acpi_pci_refresh_power_state,
 	.choose_state = acpi_pci_choose_state,
 	.set_wakeup = acpi_pci_wakeup,
 	.need_resume = acpi_pci_need_resume,