[PATCH] PCI: add pci_choose_state()

Could this go to "after 2.6.10 tree", too? It is a helper that
converts system state into PCI state. We really do not want to have
this copied into every driver, because it will need to change when
system state gets type-checked / expanded to struct.


From: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

drivers/pci/pci.c

@@ -305,6 +305,30 @@ pci_set_power_state(struct pci_dev *dev, pci_power_t state)
 	return 0;
 }
 
+/**
+ * pci_choose_state - Choose the power state of a PCI device
+ * @dev: PCI device to be suspended
+ * @state: target sleep state for the whole system
+ *
+ * Returns PCI power state suitable for given device and given system
+ * message.
+ */
+
+pci_power_t pci_choose_state(struct pci_dev *dev, u32 state)
+{
+	if (!pci_find_capability(dev, PCI_CAP_ID_PM))
+		return PCI_D0;
+
+	switch (state) {
+	case 0:	return PCI_D0;
+	case 2: return PCI_D2;
+	case 3: return PCI_D3hot;
+	default: BUG();
+	}
+}
+
+EXPORT_SYMBOL(pci_choose_state);
+
 /**
  * pci_save_state - save the PCI configuration space of a device before suspending
  * @dev: - PCI device that we're dealing with