1 files changed, 27 insertions, 2 deletions

diff --git a/drivers/sh/clk/core.c b/drivers/sh/clk/core.c
index d6702e57d428..dc8d022c07a1 100644
--- a/drivers/sh/clk/core.c
+++ b/drivers/sh/clk/core.c
@@ -34,6 +34,9 @@ static LIST_HEAD(clock_list);
 static DEFINE_SPINLOCK(clock_lock);
 static DEFINE_MUTEX(clock_list_sem);
 
+/* clock disable operations are not passed on to hardware during boot */
+static int allow_disable;
+
 void clk_rate_table_build(struct clk *clk,
                           struct cpufreq_frequency_table *freq_table,
                           int nr_freqs,
@@ -228,7 +231,7 @@ static void __clk_disable(struct clk *clk)
                 return;
 
         if (!(--clk->usecount)) {
-                if (likely(clk->ops && clk->ops->disable))
+                if (likely(allow_disable && clk->ops && clk->ops->disable))
                         clk->ops->disable(clk);
                 if (likely(clk->parent))
                         __clk_disable(clk->parent);
@@ -393,7 +396,7 @@ int clk_register(struct clk *clk)
 {
         int ret;
 
-        if (clk == NULL || IS_ERR(clk))
+        if (IS_ERR_OR_NULL(clk))
                 return -EINVAL;
 
         /*
@@ -744,3 +747,25 @@ err_out:
         return err;
 }
 late_initcall(clk_debugfs_init);
+
+static int __init clk_late_init(void)
+{
+        unsigned long flags;
+        struct clk *clk;
+
+        /* disable all clocks with zero use count */
+        mutex_lock(&clock_list_sem);
+        spin_lock_irqsave(&clock_lock, flags);
+
+        list_for_each_entry(clk, &clock_list, node)
+                if (!clk->usecount && clk->ops && clk->ops->disable)
+                        clk->ops->disable(clk);
+
+        /* from now on allow clock disable operations */
+        allow_disable = 1;
+
+        spin_unlock_irqrestore(&clock_lock, flags);
+        mutex_unlock(&clock_list_sem);
+        return 0;
+}
+late_initcall(clk_late_init);