X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=drivers%2Fclk%2Fclk.c;h=ba7d8e3e3db58035b2a199b189a94a6277fbf6df;hb=c336f64cf9a9c1bbeb0027f26c94ecfb29367ee1;hp=f13c3f4228d4d51d5649c3705fd565b4aac82913;hpb=ca4ba96e02e932a0c9997a40fd51253b5b2d0f9d;p=firefly-linux-kernel-4.4.55.git

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index f13c3f4228d4..ba7d8e3e3db5 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -1423,6 +1423,9 @@ static struct clk_core *clk_propagate_rate_change(struct clk_core *core,
 	return fail_clk;
 }
 
+static int clk_core_set_rate_nolock(struct clk_core *core,
+				    unsigned long req_rate);
+
 /*
  * walk down a subtree and set the new rates notifying the rate
  * change on the way
@@ -1443,6 +1446,15 @@ static void clk_change_rate(struct clk_core *core)
 	else if (core->parent)
 		best_parent_rate = core->parent->rate;
 
+	if (core->flags & CLK_SET_RATE_UNGATE) {
+		unsigned long flags;
+
+		clk_core_prepare(core);
+		flags = clk_enable_lock();
+		clk_core_enable(core);
+		clk_enable_unlock(flags);
+	}
+
 	if (core->new_parent && core->new_parent != core->parent) {
 		old_parent = __clk_set_parent_before(core, core->new_parent);
 		trace_clk_set_parent(core, core->new_parent);
@@ -1469,6 +1481,15 @@ static void clk_change_rate(struct clk_core *core)
 
 	core->rate = clk_recalc(core, best_parent_rate);
 
+	if (core->flags & CLK_SET_RATE_UNGATE) {
+		unsigned long flags;
+
+		flags = clk_enable_lock();
+		clk_core_disable(core);
+		clk_enable_unlock(flags);
+		clk_core_unprepare(core);
+	}
+
 	if (core->notifier_count && old_rate != core->rate)
 		__clk_notify(core, POST_RATE_CHANGE, old_rate, core->rate);
 
@@ -1489,6 +1510,12 @@ static void clk_change_rate(struct clk_core *core)
 	/* handle the new child who might not be in core->children yet */
 	if (core->new_child)
 		clk_change_rate(core->new_child);
+
+	/* handle a changed clock that needs to readjust its rate */
+	if (core->flags & CLK_KEEP_REQ_RATE && core->req_rate
+					    && core->new_rate != old_rate
+					    && core->new_rate != core->req_rate)
+		clk_core_set_rate_nolock(core, core->req_rate);
 }
 
 static int clk_core_set_rate_nolock(struct clk_core *core,
@@ -1502,8 +1529,10 @@ static int clk_core_set_rate_nolock(struct clk_core *core,
 		return 0;
 
 	/* bail early if nothing to do */
-	if (rate == clk_core_get_rate_nolock(core))
+	if (rate == clk_core_get_rate_nolock(core)) {
+		core->req_rate = req_rate;
 		return 0;
+	}
 
 	if ((core->flags & CLK_SET_RATE_GATE) && core->prepare_count)
 		return -EBUSY;
@@ -1522,11 +1551,11 @@ static int clk_core_set_rate_nolock(struct clk_core *core,
 		return -EBUSY;
 	}
 
+	core->req_rate = req_rate;
+
 	/* change the rates */
 	clk_change_rate(top);
 
-	core->req_rate = req_rate;
-
 	return ret;
 }
 
@@ -1594,9 +1623,14 @@ int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
 	clk_prepare_lock();
 
 	if (min != clk->min_rate || max != clk->max_rate) {
+		unsigned long rate = clk->core->req_rate;
+
+		if (!rate)
+			rate = clk->core->rate;
+
 		clk->min_rate = min;
 		clk->max_rate = max;
-		ret = clk_core_set_rate_nolock(clk->core, clk->core->req_rate);
+		ret = clk_core_set_rate_nolock(clk->core, rate);
 	}
 
 	clk_prepare_unlock();
@@ -1884,6 +1918,10 @@ int clk_set_phase(struct clk *clk, int degrees)
 
 	clk_prepare_lock();
 
+	/* bail early if nothing to do */
+	if (degrees == clk->core->phase)
+		goto out;
+
 	trace_clk_set_phase(clk->core, degrees);
 
 	if (clk->core->ops->set_phase)
@@ -1894,6 +1932,7 @@ int clk_set_phase(struct clk *clk, int degrees)
 	if (!ret)
 		clk->core->phase = degrees;
 
+out:
 	clk_prepare_unlock();
 
 	return ret;
@@ -2433,7 +2472,7 @@ static int __clk_init(struct device *dev, struct clk *clk_user)
 		rate = core->parent->rate;
 	else
 		rate = 0;
-	core->rate = core->req_rate = rate;
+	core->rate = rate;
 
 	/*
 	 * walk the list of orphan clocks and reparent any that are children of
@@ -2771,6 +2810,7 @@ int __clk_get(struct clk *clk)
 
 void __clk_put(struct clk *clk)
 {
+	unsigned long rate;
 	struct module *owner;
 
 	if (!clk || WARN_ON_ONCE(IS_ERR(clk)))
@@ -2779,9 +2819,13 @@ void __clk_put(struct clk *clk)
 	clk_prepare_lock();
 
 	hlist_del(&clk->clks_node);
-	if (clk->min_rate > clk->core->req_rate ||
-	    clk->max_rate < clk->core->req_rate)
-		clk_core_set_rate_nolock(clk->core, clk->core->req_rate);
+
+	rate = clk->core->req_rate;
+	if (!rate)
+		rate = clk->core->rate;
+
+	if (clk->min_rate > rate || clk->max_rate < rate)
+		clk_core_set_rate_nolock(clk->core, rate);
 
 	owner = clk->core->owner;
 	kref_put(&clk->core->ref, __clk_release);