diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 979ceb1d37e807d9e63aacd79d6a406b30b3fccc..de54fd643baf73009cd36f8bd766cfe67fff94ce 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -539,6 +539,53 @@ void pci_update_current_state(struct pci_dev *dev, pci_power_t state) } } +/** + * pci_platform_power_transition - Use platform to change device power state + * @dev: PCI device to handle. + * @state: State to put the device into. + */ +static int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state) +{ + int error; + + if (platform_pci_power_manageable(dev)) { + error = platform_pci_set_power_state(dev, state); + if (!error) + pci_update_current_state(dev, state); + } else { + error = -ENODEV; + /* Fall back to PCI_D0 if native PM is not supported */ + pci_update_current_state(dev, PCI_D0); + } + + return error; +} + +/** + * __pci_start_power_transition - Start power transition of a PCI device + * @dev: PCI device to handle. + * @state: State to put the device into. + */ +static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state) +{ + if (state == PCI_D0) + pci_platform_power_transition(dev, PCI_D0); +} + +/** + * __pci_complete_power_transition - Complete power transition of a PCI device + * @dev: PCI device to handle. + * @state: State to put the device into. + * + * This function should not be called directly by device drivers. + */ +int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state) +{ + return state > PCI_D0 ? + pci_platform_power_transition(dev, state) : -EINVAL; +} +EXPORT_SYMBOL_GPL(__pci_complete_power_transition); + /** * pci_set_power_state - Set the power state of a PCI device * @dev: PCI device to handle. @@ -575,16 +622,8 @@ int pci_set_power_state(struct pci_dev *dev, pci_power_t state) if (dev->current_state == state) return 0; - if (state == PCI_D0) { - /* - * Allow the platform to change the state, for example via ACPI - * _PR0, _PS0 and some such, but do not trust it. - */ - int ret = platform_pci_power_manageable(dev) ? - platform_pci_set_power_state(dev, PCI_D0) : 0; - if (!ret) - pci_update_current_state(dev, PCI_D0); - } + __pci_start_power_transition(dev, state); + /* This device is quirked not to be put into D3, so don't put it in D3 */ if (state == PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3)) @@ -592,14 +631,8 @@ int pci_set_power_state(struct pci_dev *dev, pci_power_t state) error = pci_raw_set_power_state(dev, state); - if (state > PCI_D0 && platform_pci_power_manageable(dev)) { - /* Allow the platform to finalize the transition */ - int ret = platform_pci_set_power_state(dev, state); - if (!ret) { - pci_update_current_state(dev, state); - error = 0; - } - } + if (!__pci_complete_power_transition(dev, state)) + error = 0; return error; } diff --git a/include/linux/pci.h b/include/linux/pci.h index 7bd624bfdcfd37945e3c59bf2a74f0d2f1dabb21..df3644132617c1ecdeaec9184a457701ac5d464b 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -689,6 +689,7 @@ size_t pci_get_rom_size(struct pci_dev *pdev, void __iomem *rom, size_t size); /* Power management related routines */ int pci_save_state(struct pci_dev *dev); int pci_restore_state(struct pci_dev *dev); +int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state); int pci_set_power_state(struct pci_dev *dev, pci_power_t state); pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state); bool pci_pme_capable(struct pci_dev *dev, pci_power_t state);