9 files changed, 165 insertions, 283 deletions

diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig
index ef38aff737eb..fd96345bc35c 100644
--- a/drivers/base/Kconfig
+++ b/drivers/base/Kconfig
@@ -71,7 +71,6 @@ config PREVENT_FIRMWARE_BUILD
 
 config FW_LOADER
         tristate "Userspace firmware loading support" if EMBEDDED
-        depends on HOTPLUG
         default y
         ---help---
           This option is provided for the case where no in-kernel-tree modules
diff --git a/drivers/base/Makefile b/drivers/base/Makefile
index c12c7f2f2a6f..5f51c3b4451e 100644
--- a/drivers/base/Makefile
+++ b/drivers/base/Makefile
@@ -19,7 +19,5 @@ obj-$(CONFIG_MODULES)	+= module.o
 endif
 obj-$(CONFIG_SYS_HYPERVISOR) += hypervisor.o
 
-ifeq ($(CONFIG_DEBUG_DRIVER),y)
-EXTRA_CFLAGS += -DDEBUG
-endif
+ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG
 
diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index eb1b7fa20dce..33c270a64db7 100644
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -440,22 +440,6 @@ static void device_remove_attrs(struct bus_type *bus, struct device *dev)
         }
 }
 
-#ifdef CONFIG_SYSFS_DEPRECATED
-static int make_deprecated_bus_links(struct device *dev)
-{
-        return sysfs_create_link(&dev->kobj,
-                                 &dev->bus->p->subsys.kobj, "bus");
-}
-
-static void remove_deprecated_bus_links(struct device *dev)
-{
-        sysfs_remove_link(&dev->kobj, "bus");
-}
-#else
-static inline int make_deprecated_bus_links(struct device *dev) { return 0; }
-static inline void remove_deprecated_bus_links(struct device *dev) { }
-#endif
-
 /**
  * bus_add_device - add device to bus
  * @dev: device being added
@@ -482,15 +466,10 @@ int bus_add_device(struct device *dev)
                                 &dev->bus->p->subsys.kobj, "subsystem");
                 if (error)
                         goto out_subsys;
-                error = make_deprecated_bus_links(dev);
-                if (error)
-                        goto out_deprecated;
                 klist_add_tail(&dev->p->knode_bus, &bus->p->klist_devices);
         }
         return 0;
 
-out_deprecated:
-        sysfs_remove_link(&dev->kobj, "subsystem");
 out_subsys:
         sysfs_remove_link(&bus->p->devices_kset->kobj, dev_name(dev));
 out_id:
@@ -530,7 +509,6 @@ void bus_remove_device(struct device *dev)
 {
         if (dev->bus) {
                 sysfs_remove_link(&dev->kobj, "subsystem");
-                remove_deprecated_bus_links(dev);
                 sysfs_remove_link(&dev->bus->p->devices_kset->kobj,
                                   dev_name(dev));
                 device_remove_attrs(dev->bus, dev);
diff --git a/drivers/base/class.c b/drivers/base/class.c
index 8e231d05b400..9c63a5687d69 100644
--- a/drivers/base/class.c
+++ b/drivers/base/class.c
@@ -184,9 +184,9 @@ int __class_register(struct class *cls, struct lock_class_key *key)
         if (!cls->dev_kobj)
                 cls->dev_kobj = sysfs_dev_char_kobj;
 
-#if defined(CONFIG_SYSFS_DEPRECATED) && defined(CONFIG_BLOCK)
+#if defined(CONFIG_BLOCK)
         /* let the block class directory show up in the root of sysfs */
-        if (cls != &block_class)
+        if (!sysfs_deprecated || cls != &block_class)
                 cp->class_subsys.kobj.kset = class_kset;
 #else
         cp->class_subsys.kobj.kset = class_kset;
@@ -276,25 +276,6 @@ void class_destroy(struct class *cls)
         class_unregister(cls);
 }
 
-#ifdef CONFIG_SYSFS_DEPRECATED
-char *make_class_name(const char *name, struct kobject *kobj)
-{
-        char *class_name;
-        int size;
-
-        size = strlen(name) + strlen(kobject_name(kobj)) + 2;
-
-        class_name = kmalloc(size, GFP_KERNEL);
-        if (!class_name)
-                return NULL;
-
-        strcpy(class_name, name);
-        strcat(class_name, ":");
-        strcat(class_name, kobject_name(kobj));
-        return class_name;
-}
-#endif
-
 /**
  * class_dev_iter_init - initialize class device iterator
  * @iter: class iterator to initialize
diff --git a/drivers/base/core.c b/drivers/base/core.c
index d1b2c9adc271..2cb49a93b1e6 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -26,6 +26,19 @@
 #include "base.h"
 #include "power/power.h"
 
+#ifdef CONFIG_SYSFS_DEPRECATED
+#ifdef CONFIG_SYSFS_DEPRECATED_V2
+long sysfs_deprecated = 1;
+#else
+long sysfs_deprecated = 0;
+#endif
+static __init int sysfs_deprecated_setup(char *arg)
+{
+        return strict_strtol(arg, 10, &sysfs_deprecated);
+}
+early_param("sysfs.deprecated", sysfs_deprecated_setup);
+#endif
+
 int (*platform_notify)(struct device *dev) = NULL;
 int (*platform_notify_remove)(struct device *dev) = NULL;
 static struct kobject *dev_kobj;
@@ -203,37 +216,6 @@ static int dev_uevent(struct kset *kset, struct kobject *kobj,
         if (dev->driver)
                 add_uevent_var(env, "DRIVER=%s", dev->driver->name);
 
-#ifdef CONFIG_SYSFS_DEPRECATED
-        if (dev->class) {
-                struct device *parent = dev->parent;
-
-                /* find first bus device in parent chain */
-                while (parent && !parent->bus)
-                        parent = parent->parent;
-                if (parent && parent->bus) {
-                        const char *path;
-
-                        path = kobject_get_path(&parent->kobj, GFP_KERNEL);
-                        if (path) {
-                                add_uevent_var(env, "PHYSDEVPATH=%s", path);
-                                kfree(path);
-                        }
-
-                        add_uevent_var(env, "PHYSDEVBUS=%s", parent->bus->name);
-
-                        if (parent->driver)
-                                add_uevent_var(env, "PHYSDEVDRIVER=%s",
-                                               parent->driver->name);
-                }
-        } else if (dev->bus) {
-                add_uevent_var(env, "PHYSDEVBUS=%s", dev->bus->name);
-
-                if (dev->driver)
-                        add_uevent_var(env, "PHYSDEVDRIVER=%s",
-                                       dev->driver->name);
-        }
-#endif
-
         /* have the bus specific function add its stuff */
         if (dev->bus && dev->bus->uevent) {
                 retval = dev->bus->uevent(dev, env);
@@ -578,24 +560,6 @@ void device_initialize(struct device *dev)
         set_dev_node(dev, -1);
 }
 
-#ifdef CONFIG_SYSFS_DEPRECATED
-static struct kobject *get_device_parent(struct device *dev,
-                                         struct device *parent)
-{
-        /* class devices without a parent live in /sys/class/<classname>/ */
-        if (dev->class && (!parent || parent->class != dev->class))
-                return &dev->class->p->class_subsys.kobj;
-        /* all other devices keep their parent */
-        else if (parent)
-                return &parent->kobj;
-
-        return NULL;
-}
-
-static inline void cleanup_device_parent(struct device *dev) {}
-static inline void cleanup_glue_dir(struct device *dev,
-                                    struct kobject *glue_dir) {}
-#else
 static struct kobject *virtual_device_parent(struct device *dev)
 {
         static struct kobject *virtual_dir = NULL;
@@ -666,6 +630,15 @@ static struct kobject *get_device_parent(struct device *dev,
                 struct kobject *parent_kobj;
                 struct kobject *k;
 
+#ifdef CONFIG_BLOCK
+                /* block disks show up in /sys/block */
+                if (sysfs_deprecated && dev->class == &block_class) {
+                        if (parent && parent->class == &block_class)
+                                return &parent->kobj;
+                        return &block_class.p->class_subsys.kobj;
+                }
+#endif
+
                 /*
                  * If we have no parent, we live in "virtual".
                  * Class-devices with a non class-device as parent, live
@@ -719,7 +692,6 @@ static void cleanup_device_parent(struct device *dev)
 {
         cleanup_glue_dir(dev, dev->kobj.parent);
 }
-#endif
 
 static void setup_parent(struct device *dev, struct device *parent)
 {
@@ -742,70 +714,29 @@ static int device_add_class_symlinks(struct device *dev)
         if (error)
                 goto out;
 
-#ifdef CONFIG_SYSFS_DEPRECATED
-        /* stacked class devices need a symlink in the class directory */
-        if (dev->kobj.parent != &dev->class->p->class_subsys.kobj &&
-            device_is_not_partition(dev)) {
-                error = sysfs_create_link(&dev->class->p->class_subsys.kobj,
-                                          &dev->kobj, dev_name(dev));
-                if (error)
-                        goto out_subsys;
-        }
-
         if (dev->parent && device_is_not_partition(dev)) {
-                struct device *parent = dev->parent;
-                char *class_name;
-
-                /*
-                 * stacked class devices have the 'device' link
-                 * pointing to the bus device instead of the parent
-                 */
-                while (parent->class && !parent->bus && parent->parent)
-                        parent = parent->parent;
-
-                error = sysfs_create_link(&dev->kobj,
-                                          &parent->kobj,
+                error = sysfs_create_link(&dev->kobj, &dev->parent->kobj,
                                           "device");
                 if (error)
-                        goto out_busid;
-
-                class_name = make_class_name(dev->class->name,
-                                                &dev->kobj);
-                if (class_name)
-                        error = sysfs_create_link(&dev->parent->kobj,
-                                                &dev->kobj, class_name);
-                kfree(class_name);
-                if (error)
-                        goto out_device;
+                        goto out_subsys;
         }
-        return 0;
 
-out_device:
-        if (dev->parent && device_is_not_partition(dev))
-                sysfs_remove_link(&dev->kobj, "device");
-out_busid:
-        if (dev->kobj.parent != &dev->class->p->class_subsys.kobj &&
-            device_is_not_partition(dev))
-                sysfs_delete_link(&dev->class->p->class_subsys.kobj, &dev->kobj,
-                                  dev_name(dev));
-#else
+#ifdef CONFIG_BLOCK
+        /* /sys/block has directories and does not need symlinks */
+        if (sysfs_deprecated && dev->class == &block_class)
+                return 0;
+#endif
+
         /* link in the class directory pointing to the device */
         error = sysfs_create_link(&dev->class->p->class_subsys.kobj,
                                   &dev->kobj, dev_name(dev));
         if (error)
-                goto out_subsys;
+                goto out_device;
 
-        if (dev->parent && device_is_not_partition(dev)) {
-                error = sysfs_create_link(&dev->kobj, &dev->parent->kobj,
-                                          "device");
-                if (error)
-                        goto out_busid;
-        }
         return 0;
 
-out_busid:
-        sysfs_delete_link(&dev->class->p->class_subsys.kobj, &dev->kobj, dev_name(dev));
-#endif
+out_device:
+        sysfs_remove_link(&dev->kobj, "device");
 
 out_subsys:
         sysfs_remove_link(&dev->kobj, "subsystem");
@@ -818,30 +749,14 @@ static void device_remove_class_symlinks(struct device *dev)
         if (!dev->class)
                 return;
 
-#ifdef CONFIG_SYSFS_DEPRECATED
-        if (dev->parent && device_is_not_partition(dev)) {
-                char *class_name;
-
-                class_name = make_class_name(dev->class->name, &dev->kobj);
-                if (class_name) {
-                        sysfs_remove_link(&dev->parent->kobj, class_name);
-                        kfree(class_name);
-                }
-                sysfs_remove_link(&dev->kobj, "device");
-        }
-
-        if (dev->kobj.parent != &dev->class->p->class_subsys.kobj &&
-            device_is_not_partition(dev))
-                sysfs_delete_link(&dev->class->p->class_subsys.kobj, &dev->kobj,
-                                  dev_name(dev));
-#else
         if (dev->parent && device_is_not_partition(dev))
                 sysfs_remove_link(&dev->kobj, "device");
-
-        sysfs_delete_link(&dev->class->p->class_subsys.kobj, &dev->kobj, dev_name(dev));
-#endif
-
         sysfs_remove_link(&dev->kobj, "subsystem");
+#ifdef CONFIG_BLOCK
+        if (sysfs_deprecated && dev->class == &block_class)
+                return;
+#endif
+        sysfs_delete_link(&dev->class->p->class_subsys.kobj, &dev->kobj, dev_name(dev));
 }
 
 /**
@@ -1613,41 +1528,23 @@ int device_rename(struct device *dev, const char *new_name)
         pr_debug("device: '%s': %s: renaming to '%s'\n", dev_name(dev),
                  __func__, new_name);
 
-#ifdef CONFIG_SYSFS_DEPRECATED
-        if ((dev->class) && (dev->parent))
-                old_class_name = make_class_name(dev->class->name, &dev->kobj);
-#endif
-
         old_device_name = kstrdup(dev_name(dev), GFP_KERNEL);
         if (!old_device_name) {
                 error = -ENOMEM;
                 goto out;
         }
 
-#ifndef CONFIG_SYSFS_DEPRECATED
         if (dev->class) {
                 error = sysfs_rename_link(&dev->class->p->class_subsys.kobj,
                         &dev->kobj, old_device_name, new_name);
                 if (error)
                         goto out;
         }
-#endif
+
         error = kobject_rename(&dev->kobj, new_name);
         if (error)
                 goto out;
 
-#ifdef CONFIG_SYSFS_DEPRECATED
-        if (old_class_name) {
-                new_class_name = make_class_name(dev->class->name, &dev->kobj);
-                if (new_class_name) {
-                        error = sysfs_rename_link(&dev->parent->kobj,
-                                                  &dev->kobj,
-                                                  old_class_name,
-                                                  new_class_name);
-                }
-        }
-#endif
-
 out:
         put_device(dev);
 
@@ -1664,40 +1561,13 @@ static int device_move_class_links(struct device *dev,
                                    struct device *new_parent)
 {
         int error = 0;
-#ifdef CONFIG_SYSFS_DEPRECATED
-        char *class_name;
 
-        class_name = make_class_name(dev->class->name, &dev->kobj);
-        if (!class_name) {
-                error = -ENOMEM;
-                goto out;
-        }
-        if (old_parent) {
-                sysfs_remove_link(&dev->kobj, "device");
-                sysfs_remove_link(&old_parent->kobj, class_name);
-        }
-        if (new_parent) {
-                error = sysfs_create_link(&dev->kobj, &new_parent->kobj,
-                                          "device");
-                if (error)
-                        goto out;
-                error = sysfs_create_link(&new_parent->kobj, &dev->kobj,
-                                          class_name);
-                if (error)
-                        sysfs_remove_link(&dev->kobj, "device");
-        } else
-                error = 0;
-out:
-        kfree(class_name);
-        return error;
-#else
         if (old_parent)
                 sysfs_remove_link(&dev->kobj, "device");
         if (new_parent)
                 error = sysfs_create_link(&dev->kobj, &new_parent->kobj,
                                           "device");
         return error;
-#endif
 }
 
 /**
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 933442f40321..cafeaaf0428f 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -27,6 +27,8 @@
 #include <asm/atomic.h>
 #include <asm/uaccess.h>
 
+static DEFINE_MUTEX(mem_sysfs_mutex);
+
 #define MEMORY_CLASS_NAME       "memory"
 
 static struct sysdev_class memory_sysdev_class = {
@@ -435,6 +437,45 @@ int __weak arch_get_memory_phys_device(unsigned long start_pfn)
         return 0;
 }
 
+struct memory_block *find_memory_block_hinted(struct mem_section *section,
+                                              struct memory_block *hint)
+{
+        struct kobject *kobj;
+        struct sys_device *sysdev;
+        struct memory_block *mem;
+        char name[sizeof(MEMORY_CLASS_NAME) + 9 + 1];
+
+        kobj = hint ? &hint->sysdev.kobj : NULL;
+
+        /*
+         * This only works because we know that section == sysdev->id
+         * slightly redundant with sysdev_register()
+         */
+        sprintf(&name[0], "%s%d", MEMORY_CLASS_NAME, __section_nr(section));
+
+        kobj = kset_find_obj_hinted(&memory_sysdev_class.kset, name, kobj);
+        if (!kobj)
+                return NULL;
+
+        sysdev = container_of(kobj, struct sys_device, kobj);
+        mem = container_of(sysdev, struct memory_block, sysdev);
+
+        return mem;
+}
+
+/*
+ * For now, we have a linear search to go find the appropriate
+ * memory_block corresponding to a particular phys_index. If
+ * this gets to be a real problem, we can always use a radix
+ * tree or something here.
+ *
+ * This could be made generic for all sysdev classes.
+ */
+struct memory_block *find_memory_block(struct mem_section *section)
+{
+        return find_memory_block_hinted(section, NULL);
+}
+
 static int add_memory_block(int nid, struct mem_section *section,
                         unsigned long state, enum mem_add_context context)
 {
@@ -445,8 +486,11 @@ static int add_memory_block(int nid, struct mem_section *section,
         if (!mem)
                 return -ENOMEM;
 
+        mutex_lock(&mem_sysfs_mutex);
+
         mem->phys_index = __section_nr(section);
         mem->state = state;
+        mem->section_count++;
         mutex_init(&mem->state_mutex);
         start_pfn = section_nr_to_pfn(mem->phys_index);
         mem->phys_device = arch_get_memory_phys_device(start_pfn);
@@ -465,53 +509,29 @@ static int add_memory_block(int nid, struct mem_section *section,
                         ret = register_mem_sect_under_node(mem, nid);
         }
 
+        mutex_unlock(&mem_sysfs_mutex);
         return ret;
 }
 
-/*
- * For now, we have a linear search to go find the appropriate
- * memory_block corresponding to a particular phys_index. If
- * this gets to be a real problem, we can always use a radix
- * tree or something here.
- *
- * This could be made generic for all sysdev classes.
- */
-struct memory_block *find_memory_block(struct mem_section *section)
-{
-        struct kobject *kobj;
-        struct sys_device *sysdev;
-        struct memory_block *mem;
-        char name[sizeof(MEMORY_CLASS_NAME) + 9 + 1];
-
-        /*
-         * This only works because we know that section == sysdev->id
-         * slightly redundant with sysdev_register()
-         */
-        sprintf(&name[0], "%s%d", MEMORY_CLASS_NAME, __section_nr(section));
-
-        kobj = kset_find_obj(&memory_sysdev_class.kset, name);
-        if (!kobj)
-                return NULL;
-
-        sysdev = container_of(kobj, struct sys_device, kobj);
-        mem = container_of(sysdev, struct memory_block, sysdev);
-
-        return mem;
-}
-
 int remove_memory_block(unsigned long node_id, struct mem_section *section,
                 int phys_device)
 {
         struct memory_block *mem;
 
+        mutex_lock(&mem_sysfs_mutex);
         mem = find_memory_block(section);
-        unregister_mem_sect_under_nodes(mem);
-        mem_remove_simple_file(mem, phys_index);
-        mem_remove_simple_file(mem, state);
-        mem_remove_simple_file(mem, phys_device);
-        mem_remove_simple_file(mem, removable);
-        unregister_memory(mem, section);
 
+        mem->section_count--;
+        if (mem->section_count == 0) {
+                unregister_mem_sect_under_nodes(mem);
+                mem_remove_simple_file(mem, phys_index);
+                mem_remove_simple_file(mem, state);
+                mem_remove_simple_file(mem, phys_device);
+                mem_remove_simple_file(mem, removable);
+                unregister_memory(mem, section);
+        }
+
+        mutex_unlock(&mem_sysfs_mutex);
         return 0;
 }
 
diff --git a/drivers/base/node.c b/drivers/base/node.c
index 2872e86837b2..ee53558b452f 100644
--- a/drivers/base/node.c
+++ b/drivers/base/node.c
@@ -409,25 +409,27 @@ static int link_mem_sections(int nid)
         unsigned long start_pfn = NODE_DATA(nid)->node_start_pfn;
         unsigned long end_pfn = start_pfn + NODE_DATA(nid)->node_spanned_pages;
         unsigned long pfn;
+        struct memory_block *mem_blk = NULL;
         int err = 0;
 
         for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
                 unsigned long section_nr = pfn_to_section_nr(pfn);
                 struct mem_section *mem_sect;
-                struct memory_block *mem_blk;
                 int ret;
 
                 if (!present_section_nr(section_nr))
                         continue;
                 mem_sect = __nr_to_section(section_nr);
-                mem_blk = find_memory_block(mem_sect);
+                mem_blk = find_memory_block_hinted(mem_sect, mem_blk);
                 ret = register_mem_sect_under_node(mem_blk, nid);
                 if (!err)
                         err = ret;
 
                 /* discard ref obtained in find_memory_block() */
-                kobject_put(&mem_blk->sysdev.kobj);
         }
+
+        if (mem_blk)
+                kobject_put(&mem_blk->sysdev.kobj);
         return err;
 }
 
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index c6c933f58102..3966e62ad019 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -192,6 +192,9 @@ int platform_device_add_resources(struct platform_device *pdev,
 {
         struct resource *r;
 
+        if (!res)
+                return 0;
+
         r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
         if (r) {
                 pdev->resource = r;
@@ -215,8 +218,12 @@ EXPORT_SYMBOL_GPL(platform_device_add_resources);
 int platform_device_add_data(struct platform_device *pdev, const void *data,
                              size_t size)
 {
-        void *d = kmemdup(data, size, GFP_KERNEL);
+        void *d;
+
+        if (!data)
+                return 0;
 
+        d = kmemdup(data, size, GFP_KERNEL);
         if (d) {
                 pdev->dev.platform_data = d;
                 return 0;
@@ -373,17 +380,13 @@ struct platform_device *__init_or_module platform_device_register_resndata(
 
         pdev->dev.parent = parent;
 
-        if (res) {
-                ret = platform_device_add_resources(pdev, res, num);
-                if (ret)
-                        goto err;
-        }
+        ret = platform_device_add_resources(pdev, res, num);
+        if (ret)
+                goto err;
 
-        if (data) {
-                ret = platform_device_add_data(pdev, data, size);
-                if (ret)
-                        goto err;
-        }
+        ret = platform_device_add_data(pdev, data, size);
+        if (ret)
+                goto err;
 
         ret = platform_device_add(pdev);
         if (ret) {
@@ -488,12 +491,12 @@ int __init_or_module platform_driver_probe(struct platform_driver *drv,
          * if the probe was successful, and make sure any forced probes of
          * new devices fail.
          */
-        spin_lock(&platform_bus_type.p->klist_drivers.k_lock);
+        spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
         drv->probe = NULL;
         if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
                 retval = -ENODEV;
         drv->driver.probe = platform_drv_probe_fail;
-        spin_unlock(&platform_bus_type.p->klist_drivers.k_lock);
+        spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
 
         if (code != retval)
                 platform_driver_unregister(drv);
@@ -530,17 +533,13 @@ struct platform_device * __init_or_module platform_create_bundle(
                 goto err_out;
         }
 
-        if (res) {
-                error = platform_device_add_resources(pdev, res, n_res);
-                if (error)
-                        goto err_pdev_put;
-        }
+        error = platform_device_add_resources(pdev, res, n_res);
+        if (error)
+                goto err_pdev_put;
 
-        if (data) {
-                error = platform_device_add_data(pdev, data, size);
-                if (error)
-                        goto err_pdev_put;
-        }
+        error = platform_device_add_data(pdev, data, size);
+        if (error)
+                goto err_pdev_put;
 
         error = platform_device_add(pdev);
         if (error)
@@ -976,6 +975,41 @@ struct bus_type platform_bus_type = {
 };
 EXPORT_SYMBOL_GPL(platform_bus_type);
 
+/**
+ * platform_bus_get_pm_ops() - return pointer to busses dev_pm_ops
+ *
+ * This function can be used by platform code to get the current
+ * set of dev_pm_ops functions used by the platform_bus_type.
+ */
+const struct dev_pm_ops * __init platform_bus_get_pm_ops(void)
+{
+        return platform_bus_type.pm;
+}
+
+/**
+ * platform_bus_set_pm_ops() - update dev_pm_ops for the platform_bus_type
+ *
+ * @pm: pointer to new dev_pm_ops struct to be used for platform_bus_type
+ *
+ * Platform code can override the dev_pm_ops methods of
+ * platform_bus_type by using this function.  It is expected that
+ * platform code will first do a platform_bus_get_pm_ops(), then
+ * kmemdup it, then customize selected methods and pass a pointer to
+ * the new struct dev_pm_ops to this function.
+ *
+ * Since platform-specific code is customizing methods for *all*
+ * devices (not just platform-specific devices) it is expected that
+ * any custom overrides of these functions will keep existing behavior
+ * and simply extend it.  For example, any customization of the
+ * runtime PM methods should continue to call the pm_generic_*
+ * functions as the default ones do in addition to the
+ * platform-specific behavior.
+ */
+void __init platform_bus_set_pm_ops(const struct dev_pm_ops *pm)
+{
+        platform_bus_type.pm = pm;
+}
+
 int __init platform_bus_init(void)
 {
         int error;
diff --git a/drivers/base/sys.c b/drivers/base/sys.c
index 9354dc10a363..1667aaf4fde6 100644
--- a/drivers/base/sys.c
+++ b/drivers/base/sys.c
@@ -432,13 +432,13 @@ int sysdev_suspend(pm_message_t state)
         /* resume current sysdev */
 cls_driver:
         drv = NULL;
-        printk(KERN_ERR "Class suspend failed for %s\n",
-                kobject_name(&sysdev->kobj));
+        printk(KERN_ERR "Class suspend failed for %s: %d\n",
+                kobject_name(&sysdev->kobj), ret);
 
 aux_driver:
         if (drv)
-                printk(KERN_ERR "Class driver suspend failed for %s\n",
-                                kobject_name(&sysdev->kobj));
+                printk(KERN_ERR "Class driver suspend failed for %s: %d\n",
+                                kobject_name(&sysdev->kobj), ret);
         list_for_each_entry(err_drv, &cls->drivers, entry) {
                 if (err_drv == drv)
                         break;