+/**
+ * pci_back_from_sleep - turn PCI device on during system-wide transition into
+ * the working state a sleep state
+ * @dev: Device to handle.
+ *
+ * Disable device's sytem wake-up capability and put it into D0.
+ */
+int pci_back_from_sleep(struct pci_dev *dev)
+{
+ pci_enable_wake(dev, PCI_D0, false);
+ return pci_set_power_state(dev, PCI_D0);
+}
+
+/**
+ * pci_pm_init - Initialize PM functions of given PCI device
+ * @dev: PCI device to handle.
+ */
+void pci_pm_init(struct pci_dev *dev)
+{
+ int pm;
+ u16 pmc;
+
+ dev->pm_cap = 0;
+
+ /* find PCI PM capability in list */
+ pm = pci_find_capability(dev, PCI_CAP_ID_PM);
+ if (!pm)
+ return;
+ /* Check device's ability to generate PME# */
+ pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
+
+ if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
+ dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
+ pmc & PCI_PM_CAP_VER_MASK);
+ return;
+ }
+
+ dev->pm_cap = pm;
+
+ dev->d1_support = false;
+ dev->d2_support = false;
+ if (!pci_no_d1d2(dev)) {
+ if (pmc & PCI_PM_CAP_D1) {
+ dev_printk(KERN_DEBUG, &dev->dev, "supports D1\n");
+ dev->d1_support = true;
+ }
+ if (pmc & PCI_PM_CAP_D2) {
+ dev_printk(KERN_DEBUG, &dev->dev, "supports D2\n");
+ dev->d2_support = true;
+ }
+ }
+
+ pmc &= PCI_PM_CAP_PME_MASK;
+ if (pmc) {
+ dev_printk(KERN_INFO, &dev->dev,
+ "PME# supported from%s%s%s%s%s\n",
+ (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
+ (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
+ (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
+ (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
+ (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
+ dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT;
+ /*
+ * Make device's PM flags reflect the wake-up capability, but
+ * let the user space enable it to wake up the system as needed.
+ */
+ device_set_wakeup_capable(&dev->dev, true);
+ device_set_wakeup_enable(&dev->dev, false);
+ /* Disable the PME# generation functionality */
+ pci_pme_active(dev, false);
+ } else {
+ dev->pme_support = 0;
+ }