PCI: add D3 power state avoidance quirk

[~andy/linux] / drivers / pci / pci.c

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index d00f0e0d84537168c3464d476db3485753924450..0a3d856833fcaf669482eb19cf7cbe73a91f45d9 100644 (file)
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -572,6 +572,10 @@ int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
                if (!ret)
                        pci_update_current_state(dev);
        }
+       /* 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))
+               return 0;
 
        error = pci_raw_set_power_state(dev, state);
 
@@ -1040,7 +1044,7 @@ int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
  * @dev: PCI device to handle.
  * @state: PCI state from which device will issue PME#.
  */
-static bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
+bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
 {
        if (!dev->pm_cap)
                return false;
@@ -1123,17 +1127,16 @@ int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable)
 }
 
 /**
- * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state
- * @dev: Device to handle.
+ * pci_target_state - find an appropriate low power state for a given PCI dev
+ * @dev: PCI device
  *
- * Choose the power state appropriate for the device depending on whether
- * it can wake up the system and/or is power manageable by the platform
- * (PCI_D3hot is the default) and put the device into that state.
+ * Use underlying platform code to find a supported low power state for @dev.
+ * If the platform can't manage @dev, return the deepest state from which it
+ * can generate wake events, based on any available PME info.
  */
-int pci_prepare_to_sleep(struct pci_dev *dev)
+pci_power_t pci_target_state(struct pci_dev *dev)
 {
        pci_power_t target_state = PCI_D3hot;
-       int error;
 
        if (platform_pci_power_manageable(dev)) {
                /*
@@ -1160,7 +1163,7 @@ int pci_prepare_to_sleep(struct pci_dev *dev)
                 * to generate PME#.
                 */
                if (!dev->pm_cap)
-                       return -EIO;
+                       return PCI_POWER_ERROR;
 
                if (dev->pme_support) {
                        while (target_state
@@ -1169,6 +1172,25 @@ int pci_prepare_to_sleep(struct pci_dev *dev)
                }
        }
 
+       return target_state;
+}
+
+/**
+ * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state
+ * @dev: Device to handle.
+ *
+ * Choose the power state appropriate for the device depending on whether
+ * it can wake up the system and/or is power manageable by the platform
+ * (PCI_D3hot is the default) and put the device into that state.
+ */
+int pci_prepare_to_sleep(struct pci_dev *dev)
+{
+       pci_power_t target_state = pci_target_state(dev);
+       int error;
+
+       if (target_state == PCI_POWER_ERROR)
+               return -EIO;
+
        pci_enable_wake(dev, target_state, true);
 
        error = pci_set_power_state(dev, target_state);
@@ -1918,7 +1940,9 @@ EXPORT_SYMBOL(pci_select_bars);
 EXPORT_SYMBOL(pci_set_power_state);
 EXPORT_SYMBOL(pci_save_state);
 EXPORT_SYMBOL(pci_restore_state);
+EXPORT_SYMBOL(pci_pme_capable);
 EXPORT_SYMBOL(pci_enable_wake);
+EXPORT_SYMBOL(pci_target_state);
 EXPORT_SYMBOL(pci_prepare_to_sleep);
 EXPORT_SYMBOL(pci_back_from_sleep);
 EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);