1 files changed, 110 insertions, 0 deletions

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index fe3693de7ba3..f8316a05ede7 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1341,6 +1341,100 @@ static int acpi_bus_scan_fixed(struct acpi_device *root)
         return_VALUE(result);
 }
 
+
+static inline struct acpi_device * to_acpi_dev(struct device * dev)
+{
+        return container_of(dev, struct acpi_device, dev);
+}
+
+
+static int root_suspend(struct acpi_device * acpi_dev, pm_message_t state)
+{
+        struct acpi_device * dev, * next;
+        int result;
+
+        spin_lock(&acpi_device_lock);
+        list_for_each_entry_safe_reverse(dev, next, &acpi_device_list, g_list) {
+                if (dev->driver && dev->driver->ops.suspend) {
+                        spin_unlock(&acpi_device_lock);
+                        result = dev->driver->ops.suspend(dev, 0);
+                        if (result) {
+                                printk(KERN_ERR PREFIX "[%s - %s] Suspend failed: %d\n",
+                                       acpi_device_name(dev),
+                                       acpi_device_bid(dev), result);
+                        }
+                        spin_lock(&acpi_device_lock);
+                }
+        }
+        spin_unlock(&acpi_device_lock);
+        return 0;
+}
+
+
+static int acpi_device_suspend(struct device * dev, pm_message_t state)
+{
+        struct acpi_device * acpi_dev = to_acpi_dev(dev);
+
+        /*
+         * For now, we should only register 1 generic device -
+         * the ACPI root device - and from there, we walk the
+         * tree of ACPI devices to suspend each one using the
+         * ACPI driver methods.
+         */
+        if (acpi_dev->handle == ACPI_ROOT_OBJECT)
+                root_suspend(acpi_dev, state);
+        return 0;
+}
+
+
+
+static int root_resume(struct acpi_device * acpi_dev)
+{
+        struct acpi_device * dev, * next;
+        int result;
+
+        spin_lock(&acpi_device_lock);
+        list_for_each_entry_safe(dev, next, &acpi_device_list, g_list) {
+                if (dev->driver && dev->driver->ops.resume) {
+                        spin_unlock(&acpi_device_lock);
+                        result = dev->driver->ops.resume(dev, 0);
+                        if (result) {
+                                printk(KERN_ERR PREFIX "[%s - %s] resume failed: %d\n",
+                                       acpi_device_name(dev),
+                                       acpi_device_bid(dev), result);
+                        }
+                        spin_lock(&acpi_device_lock);
+                }
+        }
+        spin_unlock(&acpi_device_lock);
+        return 0;
+}
+
+
+static int acpi_device_resume(struct device * dev)
+{
+        struct acpi_device * acpi_dev = to_acpi_dev(dev);
+
+        /*
+         * For now, we should only register 1 generic device -
+         * the ACPI root device - and from there, we walk the
+         * tree of ACPI devices to resume each one using the
+         * ACPI driver methods.
+         */
+        if (acpi_dev->handle == ACPI_ROOT_OBJECT)
+                root_resume(acpi_dev);
+        return 0;
+}
+
+
+struct bus_type acpi_bus_type = {
+        .name           = "acpi",
+        .suspend        = acpi_device_suspend,
+        .resume         = acpi_device_resume,
+};
+
+
+
 static int __init acpi_scan_init(void)
 {
         int result;
@@ -1353,6 +1447,12 @@ static int __init acpi_scan_init(void)
 
         kset_register(&acpi_namespace_kset);
 
+        result = bus_register(&acpi_bus_type);
+        if (result) {
+                /* We don't want to quit even if we failed to add suspend/resume */
+                printk(KERN_ERR PREFIX "Could not register bus type\n");
+        }
+
         /*
          * Create the root device in the bus's device tree
          */
@@ -1362,6 +1462,16 @@ static int __init acpi_scan_init(void)
                 goto Done;
 
         result = acpi_start_single_object(acpi_root);
+        if (result)
+                goto Done;
+
+        acpi_root->dev.bus = &acpi_bus_type;
+        snprintf(acpi_root->dev.bus_id, BUS_ID_SIZE, "%s", acpi_bus_type.name);
+        result = device_register(&acpi_root->dev);
+        if (result) {
+                /* We don't want to quit even if we failed to add suspend/resume */
+                printk(KERN_ERR PREFIX "Could not register device\n");
+        }
 
         /*
          * Enumerate devices in the ACPI namespace.