8 files changed, 122 insertions, 8 deletions

diff --git a/drivers/acpi/container.c b/drivers/acpi/container.c
index 83d232c10f13..0b6ae6eb5c4a 100644
--- a/drivers/acpi/container.c
+++ b/drivers/acpi/container.c
@@ -27,8 +27,7 @@
  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  */
 #include <linux/acpi.h>
-
-#include "internal.h"
+#include <linux/container.h>
 
 #include "internal.h"
 
@@ -44,16 +43,56 @@ static const struct acpi_device_id container_device_ids[] = {
         {"", 0},
 };
 
+static int acpi_container_offline(struct container_dev *cdev)
+{
+        struct acpi_device *adev = ACPI_COMPANION(&cdev->dev);
+        struct acpi_device *child;
+
+        /* Check all of the dependent devices' physical companions. */
+        list_for_each_entry(child, &adev->children, node)
+                if (!acpi_scan_is_offline(child, false))
+                        return -EBUSY;
+
+        return 0;
+}
+
+static void acpi_container_release(struct device *dev)
+{
+        kfree(to_container_dev(dev));
+}
+
 static int container_device_attach(struct acpi_device *adev,
                                    const struct acpi_device_id *not_used)
 {
-        kobject_uevent(&adev->dev.kobj, KOBJ_ONLINE);
+        struct container_dev *cdev;
+        struct device *dev;
+        int ret;
+
+        cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
+        if (!cdev)
+                return -ENOMEM;
+
+        cdev->offline = acpi_container_offline;
+        dev = &cdev->dev;
+        dev->bus = &container_subsys;
+        dev_set_name(dev, "%s", dev_name(&adev->dev));
+        ACPI_COMPANION_SET(dev, adev);
+        dev->release = acpi_container_release;
+        ret = device_register(dev);
+        if (ret)
+                return ret;
+
+        adev->driver_data = dev;
         return 1;
 }
 
 static void container_device_detach(struct acpi_device *adev)
 {
-        kobject_uevent(&adev->dev.kobj, KOBJ_OFFLINE);
+        struct device *dev = acpi_driver_data(adev);
+
+        adev->driver_data = NULL;
+        if (dev)
+                device_unregister(dev);
 }
 
 static struct acpi_scan_handler container_handler = {
@@ -62,6 +101,7 @@ static struct acpi_scan_handler container_handler = {
         .detach = container_device_detach,
         .hotplug = {
                 .enabled = true,
+                .demand_offline = true,
         },
 };
 
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
index b125fdb0b30c..3375129bb5b7 100644
--- a/drivers/acpi/internal.h
+++ b/drivers/acpi/internal.h
@@ -73,6 +73,7 @@ static inline void acpi_lpss_init(void) {}
 #endif
 
 bool acpi_queue_hotplug_work(struct work_struct *work);
+bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent);
 
 /* --------------------------------------------------------------------------
                      Device Node Initialization / Removal
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 65243b9dd868..32b340171d41 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -126,7 +126,7 @@ acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, cha
 }
 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
 
-static bool acpi_scan_is_offline(struct acpi_device *adev)
+bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
 {
         struct acpi_device_physical_node *pn;
         bool offline = true;
@@ -135,7 +135,9 @@ static bool acpi_scan_is_offline(struct acpi_device *adev)
 
         list_for_each_entry(pn, &adev->physical_node_list, node)
                 if (device_supports_offline(pn->dev) && !pn->dev->offline) {
-                        kobject_uevent(&pn->dev->kobj, KOBJ_CHANGE);
+                        if (uevent)
+                                kobject_uevent(&pn->dev->kobj, KOBJ_CHANGE);
+
                         offline = false;
                         break;
                 }
@@ -267,7 +269,7 @@ static int acpi_scan_hot_remove(struct acpi_device *device)
         acpi_status status;
 
         if (device->handler->hotplug.demand_offline && !acpi_force_hot_remove) {
-                if (!acpi_scan_is_offline(device))
+                if (!acpi_scan_is_offline(device, true))
                         return -EBUSY;
         } else {
                 int error = acpi_scan_try_to_offline(device);
diff --git a/drivers/base/Makefile b/drivers/base/Makefile
index 94e8a80e87f8..d08c9d3b1d37 100644
--- a/drivers/base/Makefile
+++ b/drivers/base/Makefile
@@ -4,7 +4,7 @@ obj-y			:= core.o bus.o dd.o syscore.o \
                            driver.o class.o platform.o \
                            cpu.o firmware.o init.o map.o devres.o \
                            attribute_container.o transport_class.o \
-                           topology.o
+                           topology.o container.o
 obj-$(CONFIG_DEVTMPFS)  += devtmpfs.o
 obj-$(CONFIG_DMA_CMA) += dma-contiguous.o
 obj-y                   += power/
diff --git a/drivers/base/base.h b/drivers/base/base.h
index 2cbc6774f4cd..24f424249d9b 100644
--- a/drivers/base/base.h
+++ b/drivers/base/base.h
@@ -100,6 +100,7 @@ static inline int hypervisor_init(void) { return 0; }
 #endif
 extern int platform_bus_init(void);
 extern void cpu_dev_init(void);
+extern void container_dev_init(void);
 
 struct kobject *virtual_device_parent(struct device *dev);
 
diff --git a/drivers/base/container.c b/drivers/base/container.c
new file mode 100644
index 000000000000..ecbfbe2e908f
--- /dev/null
+++ b/drivers/base/container.c
@@ -0,0 +1,44 @@
+/*
+ * System bus type for containers.
+ *
+ * Copyright (C) 2013, Intel Corporation
+ * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/container.h>
+
+#include "base.h"
+
+#define CONTAINER_BUS_NAME      "container"
+
+static int trivial_online(struct device *dev)
+{
+        return 0;
+}
+
+static int container_offline(struct device *dev)
+{
+        struct container_dev *cdev = to_container_dev(dev);
+
+        return cdev->offline ? cdev->offline(cdev) : 0;
+}
+
+struct bus_type container_subsys = {
+        .name = CONTAINER_BUS_NAME,
+        .dev_name = CONTAINER_BUS_NAME,
+        .online = trivial_online,
+        .offline = container_offline,
+};
+
+void __init container_dev_init(void)
+{
+        int ret;
+
+        ret = subsys_system_register(&container_subsys, NULL);
+        if (ret)
+                pr_err("%s() failed: %d\n", __func__, ret);
+}
diff --git a/drivers/base/init.c b/drivers/base/init.c
index c16f0b808a17..da033d3bab3c 100644
--- a/drivers/base/init.c
+++ b/drivers/base/init.c
@@ -33,4 +33,5 @@ void __init driver_init(void)
         platform_bus_init();
         cpu_dev_init();
         memory_dev_init();
+        container_dev_init();
 }
diff --git a/include/linux/container.h b/include/linux/container.h
new file mode 100644
index 000000000000..3c03e6fd2035
--- /dev/null
+++ b/include/linux/container.h
@@ -0,0 +1,25 @@
+/*
+ * Definitions for container bus type.
+ *
+ * Copyright (C) 2013, Intel Corporation
+ * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/device.h>
+
+/* drivers/base/power/container.c */
+extern struct bus_type container_subsys;
+
+struct container_dev {
+        struct device dev;
+        int (*offline)(struct container_dev *cdev);
+};
+
+static inline struct container_dev *to_container_dev(struct device *dev)
+{
+        return container_of(dev, struct container_dev, dev);
+}