reset: use kref for reference counting

Use kref for reference counting and enjoy the advantages of refcount_t.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

diff --git a/drivers/reset/core.c b/drivers/reset/core.c
index cd739d2..0090784 100644 (file)
--- a/drivers/reset/core.c
+++ b/drivers/reset/core.c
@@ -13,6 +13,7 @@
 #include <linux/err.h>
 #include <linux/export.h>
 #include <linux/kernel.h>
+#include <linux/kref.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/reset.h>
@@ -40,7 +41,7 @@ struct reset_control {
        struct reset_controller_dev *rcdev;
        struct list_head list;
        unsigned int id;
-       unsigned int refcnt;
+       struct kref refcnt;
        bool shared;
        atomic_t deassert_count;
        atomic_t triggered_count;
@@ -288,7 +289,7 @@ static struct reset_control *__reset_control_get_internal(
                        if (WARN_ON(!rstc->shared || !shared))
                                return ERR_PTR(-EBUSY);
 
-                       rstc->refcnt++;
+                       kref_get(&rstc->refcnt);
                        return rstc;
                }
        }
@@ -302,18 +303,18 @@ static struct reset_control *__reset_control_get_internal(
        rstc->rcdev = rcdev;
        list_add(&rstc->list, &rcdev->reset_control_head);
        rstc->id = index;
-       rstc->refcnt = 1;
+       kref_init(&rstc->refcnt);
        rstc->shared = shared;
 
        return rstc;
 }
 
-static void __reset_control_put_internal(struct reset_control *rstc)
+static void __reset_control_release(struct kref *kref)
 {
-       lockdep_assert_held(&reset_list_mutex);
+       struct reset_control *rstc = container_of(kref, struct reset_control,
+                                                 refcnt);
 
-       if (--rstc->refcnt)
-               return;
+       lockdep_assert_held(&reset_list_mutex);
 
        module_put(rstc->rcdev->owner);
 
@@ -321,6 +322,13 @@ static void __reset_control_put_internal(struct reset_control *rstc)
        kfree(rstc);
 }
 
+static void __reset_control_put_internal(struct reset_control *rstc)
+{
+       lockdep_assert_held(&reset_list_mutex);
+
+       kref_put(&rstc->refcnt, __reset_control_release);
+}
+
 struct reset_control *__of_reset_control_get(struct device_node *node,
                                     const char *id, int index, bool shared,
                                     bool optional)
@@ -400,7 +408,6 @@ EXPORT_SYMBOL_GPL(__reset_control_get);
  * reset_control_put - free the reset controller
  * @rstc: reset controller
  */
-
 void reset_control_put(struct reset_control *rstc)
 {
        if (IS_ERR_OR_NULL(rstc))