Merge tag 'driver-core-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core patches for 3.4-rc1 from Greg KH:
 "Here's the big driver core merge for 3.4-rc1.

  Lots of various things here, sysfs fixes/tweaks (with the nlink
  breakage reverted), dynamic debugging updates, w1 drivers, hyperv
  driver updates, and a variety of other bits and pieces, full
  information in the shortlog."

* tag 'driver-core-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (78 commits)
  Tools: hv: Support enumeration from all the pools
  Tools: hv: Fully support the new KVP verbs in the user level daemon
  Drivers: hv: Support the newly introduced KVP messages in the driver
  Drivers: hv: Add new message types to enhance KVP
  regulator: Support driver probe deferral
  Revert "sysfs: Kill nlink counting."
  uevent: send events in correct order according to seqnum (v3)
  driver core: minor comment formatting cleanups
  driver core: move the deferred probe pointer into the private area
  drivercore: Add driver probe deferral mechanism
  DS2781 Maxim Stand-Alone Fuel Gauge battery and w1 slave drivers
  w1_bq27000: Only one thread can access the bq27000 at a time.
  w1_bq27000 - remove w1_bq27000_write
  w1_bq27000: remove unnecessary NULL test.
  sysfs: Fix memory leak in sysfs_sd_setsecdata().
  intel_idle: Revert change of auto_demotion_disable_flags for Nehalem
  w1: Fix w1_bq27000
  driver-core: documentation: fix up Greg's email address
  powernow-k6: Really enable auto-loading
  powernow-k7: Fix CPU family number
  ...

1 files changed, 5 insertions, 30 deletions

diff --git a/drivers/base/driver.c b/drivers/base/driver.c
index b631f7c5945..60e4f77ca66 100644
--- a/drivers/base/driver.c
+++ b/drivers/base/driver.c
@@ -153,34 +153,6 @@ int driver_add_kobj(struct device_driver *drv, struct kobject *kobj,
 }
 EXPORT_SYMBOL_GPL(driver_add_kobj);
 
-/**
- * get_driver - increment driver reference count.
- * @drv: driver.
- */
-struct device_driver *get_driver(struct device_driver *drv)
-{
-	if (drv) {
-		struct driver_private *priv;
-		struct kobject *kobj;
-
-		kobj = kobject_get(&drv->p->kobj);
-		priv = to_driver(kobj);
-		return priv->driver;
-	}
-	return NULL;
-}
-EXPORT_SYMBOL_GPL(get_driver);
-
-/**
- * put_driver - decrement driver's refcount.
- * @drv: driver.
- */
-void put_driver(struct device_driver *drv)
-{
-	kobject_put(&drv->p->kobj);
-}
-EXPORT_SYMBOL_GPL(put_driver);
-
 static int driver_add_groups(struct device_driver *drv,
 			     const struct attribute_group **groups)
 {
@@ -234,7 +206,6 @@ int driver_register(struct device_driver *drv)
 
 	other = driver_find(drv->name, drv->bus);
 	if (other) {
-		put_driver(other);
 		printk(KERN_ERR "Error: Driver '%s' is already registered, "
 			"aborting...\n", drv->name);
 		return -EBUSY;
@@ -275,7 +246,9 @@ EXPORT_SYMBOL_GPL(driver_unregister);
  * Call kset_find_obj() to iterate over list of drivers on
  * a bus to find driver by name. Return driver if found.
  *
- * Note that kset_find_obj increments driver's reference count.
+ * This routine provides no locking to prevent the driver it returns
+ * from being unregistered or unloaded while the caller is using it.
+ * The caller is responsible for preventing this.
  */
 struct device_driver *driver_find(const char *name, struct bus_type *bus)
 {
@@ -283,6 +256,8 @@ struct device_driver *driver_find(const char *name, struct bus_type *bus)
 	struct driver_private *priv;
 
 	if (k) {
+		/* Drop reference added by kset_find_obj() */
+		kobject_put(k);
 		priv = to_driver(k);
 		return priv->driver;
 	}