From bac2a909a096c9110525c18cbb8ce73c660d5f71 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 21 Jan 2015 02:17:42 +0100 Subject: PCI / PM: Avoid resuming PCI devices during system suspend Commit f25c0ae2b4c4 (ACPI / PM: Avoid resuming devices in ACPI PM domain during system suspend) modified the ACPI PM domain's system suspend callbacks to allow devices attached to it to be left in the runtime-suspended state during system suspend so as to optimize the suspend process. This was based on the general mechanism introduced by commit aae4518b3124 (PM / sleep: Mechanism to avoid resuming runtime-suspended devices unnecessarily). Extend that approach to PCI devices by modifying the PCI bus type's ->prepare callback to return 1 for devices that are runtime-suspended when it is being executed and that are in a suitable power state and need not be resumed going forward. Signed-off-by: Rafael J. Wysocki Acked-by: Bjorn Helgaas --- drivers/pci/pci.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index cab05f31223f..7a671abceccc 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -521,6 +521,11 @@ static inline int platform_pci_run_wake(struct pci_dev *dev, bool enable) pci_platform_pm->run_wake(dev, enable) : -ENODEV; } +static inline bool platform_pci_need_resume(struct pci_dev *dev) +{ + return pci_platform_pm ? pci_platform_pm->need_resume(dev) : false; +} + /** * pci_raw_set_power_state - Use PCI PM registers to set the power state of * given PCI device @@ -1999,6 +2004,27 @@ bool pci_dev_run_wake(struct pci_dev *dev) } EXPORT_SYMBOL_GPL(pci_dev_run_wake); +/** + * pci_dev_keep_suspended - Check if the device can stay in the suspended state. + * @pci_dev: Device to check. + * + * Return 'true' if the device is runtime-suspended, it doesn't have to be + * reconfigured due to wakeup settings difference between system and runtime + * suspend and the current power state of it is suitable for the upcoming + * (system) transition. + */ +bool pci_dev_keep_suspended(struct pci_dev *pci_dev) +{ + struct device *dev = &pci_dev->dev; + + if (!pm_runtime_suspended(dev) + || (device_can_wakeup(dev) && !device_may_wakeup(dev)) + || platform_pci_need_resume(pci_dev)) + return false; + + return pci_target_state(pci_dev) == pci_dev->current_state; +} + void pci_config_pm_runtime_get(struct pci_dev *pdev) { struct device *dev = &pdev->dev; -- cgit v1.2.3