PCI/ASPM: Add pcie_aspm_enabled()

[linux-2.6-microblaze.git] / drivers / pci / pcie / aspm.c

diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index e44af7f..464f8f9 100644 (file)
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -1170,6 +1170,26 @@ static int pcie_aspm_get_policy(char *buffer, const struct kernel_param *kp)
 module_param_call(policy, pcie_aspm_set_policy, pcie_aspm_get_policy,
        NULL, 0644);
 
+/**
+ * pcie_aspm_enabled - Check if PCIe ASPM has been enabled for a device.
+ * @pdev: Target device.
+ */
+bool pcie_aspm_enabled(struct pci_dev *pdev)
+{
+       struct pci_dev *bridge = pci_upstream_bridge(pdev);
+       bool ret;
+
+       if (!bridge)
+               return false;
+
+       mutex_lock(&aspm_lock);
+       ret = bridge->link_state ? !!bridge->link_state->aspm_enabled : false;
+       mutex_unlock(&aspm_lock);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(pcie_aspm_enabled);
+
 #ifdef CONFIG_PCIEASPM_DEBUG
 static ssize_t link_state_show(struct device *dev,
                struct device_attribute *attr,