clk: abstract parent cache

[mirror_ubuntu-zesty-kernel.git] / drivers / clk / clk.c

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 54a191c5bbf0e3f4c1b23807c12a59cdb0d74031..42c15a8ba34d30d75f01e563d53146f3cda25265 100644 (file)
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -559,6 +559,19 @@ struct clk *__clk_get_parent(struct clk *clk)
        return !clk ? NULL : clk->parent;
 }
 
+struct clk *clk_get_parent_by_index(struct clk *clk, u8 index)
+{
+       if (!clk || index >= clk->num_parents)
+               return NULL;
+       else if (!clk->parents)
+               return __clk_lookup(clk->parent_names[index]);
+       else if (!clk->parents[index])
+               return clk->parents[index] =
+                       __clk_lookup(clk->parent_names[index]);
+       else
+               return clk->parents[index];
+}
+
 unsigned int __clk_get_enable_count(struct clk *clk)
 {
        return !clk ? 0 : clk->enable_count;
@@ -702,7 +715,7 @@ void __clk_unprepare(struct clk *clk)
 
 /**
  * clk_unprepare - undo preparation of a clock source
- * @clk: the clk being unprepare
+ * @clk: the clk being unprepared
  *
  * clk_unprepare may sleep, which differentiates it from clk_disable.  In a
  * simple case, clk_unprepare can be used instead of clk_disable to gate a clk
@@ -869,6 +882,7 @@ EXPORT_SYMBOL_GPL(clk_enable);
 /**
  * __clk_round_rate - round the given rate for a clk
  * @clk: round the rate of this clock
+ * @rate: the rate which is to be rounded
  *
  * Caller must hold prepare_lock.  Useful for clk_ops such as .set_rate
  */
@@ -956,7 +970,7 @@ static int __clk_notify(struct clk *clk, unsigned long msg,
  *
  * Walks the subtree of clks starting with clk and recalculates rates as it
  * goes.  Note that if a clk does not implement the .recalc_rate callback then
- * it is assumed that the clock will take on the rate of it's parent.
+ * it is assumed that the clock will take on the rate of its parent.
  *
  * clk_recalc_rates also propagates the POST_RATE_CHANGE notification,
  * if necessary.
@@ -1026,7 +1040,7 @@ EXPORT_SYMBOL_GPL(clk_get_rate);
  * pre-rate change notifications and returns early if no clks in the
  * subtree have subscribed to the notifications.  Note that if a clk does not
  * implement the .recalc_rate callback then it is assumed that the clock will
- * take on the rate of it's parent.
+ * take on the rate of its parent.
  *
  * Caller must hold prepare_lock.
  */
@@ -1198,7 +1212,7 @@ static void clk_change_rate(struct clk *clk)
  * outcome of clk's .round_rate implementation.  If *parent_rate is unchanged
  * after calling .round_rate then upstream parent propagation is ignored.  If
  * *parent_rate comes back with a new rate for clk's parent then we propagate
- * up to clk's parent and set it's rate.  Upward propagation will continue
+ * up to clk's parent and set its rate.  Upward propagation will continue
  * until either a clk does not support the CLK_SET_RATE_PARENT flag or
  * .round_rate stops requesting changes to clk's parent_rate.
  *
@@ -1315,13 +1329,7 @@ static struct clk *__clk_init_parent(struct clk *clk)
                        kzalloc((sizeof(struct clk*) * clk->num_parents),
                                        GFP_KERNEL);
 
-       if (!clk->parents)
-               ret = __clk_lookup(clk->parent_names[index]);
-       else if (!clk->parents[index])
-               ret = clk->parents[index] =
-                       __clk_lookup(clk->parent_names[index]);
-       else
-               ret = clk->parents[index];
+       ret = clk_get_parent_by_index(clk, index);
 
 out:
        return ret;
@@ -1648,7 +1656,7 @@ int __clk_init(struct device *dev, struct clk *clk)
         * The .init callback is not used by any of the basic clock types, but
         * exists for weird hardware that must perform initialization magic.
         * Please consider other ways of solving initialization problems before
-        * using this callback, as it's use is discouraged.
+        * using this callback, as its use is discouraged.
         */
        if (clk->ops->init)
                clk->ops->init(clk->hw);
@@ -1675,7 +1683,7 @@ out:
  * very large numbers of clocks that need to be statically initialized.  It is
  * a layering violation to include clk-private.h from any code which implements
  * a clock's .ops; as such any statically initialized clock data MUST be in a
- * separate C file from the logic that implements it's operations.  Returns 0
+ * separate C file from the logic that implements its operations.  Returns 0
  * on success, otherwise an error code.
  */
 struct clk *__clk_register(struct device *dev, struct clk_hw *hw)