From c21794d0eea0dad22cb659ca41b13464f0ee1212 Mon Sep 17 00:00:00 2001
From: Sascha Hauer <s.hauer@pengutronix.de>
Date: Wed, 1 Feb 2017 15:56:35 +0100
Subject: clk: Keep enable count consistent over reparent

When reparenting a clock we have to make sure the new parent is enabled
when the clock was enabled on the old parent. Also we have to decrease
the old parents use counter when the clock was enabled.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 drivers/clk/clk.c | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

(limited to 'drivers/clk/clk.c')

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 1566beabda..6f3053727c 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -173,14 +173,15 @@ struct clk *clk_lookup(const char *name)
 	return ERR_PTR(-ENODEV);
 }
 
-int clk_set_parent(struct clk *clk, struct clk *parent)
+int clk_set_parent(struct clk *clk, struct clk *newparent)
 {
-	int i;
+	int i, ret;
+	struct clk *curparent = clk_get_parent(clk);
 
 	if (IS_ERR(clk))
 		return PTR_ERR(clk);
-	if (IS_ERR(parent))
-		return PTR_ERR(parent);
+	if (IS_ERR(newparent))
+		return PTR_ERR(newparent);
 
 	if (!clk->num_parents)
 		return -EINVAL;
@@ -192,14 +193,22 @@ int clk_set_parent(struct clk *clk, struct clk *parent)
 			clk->parents[i] = clk_lookup(clk->parent_names[i]);
 
 		if (!IS_ERR_OR_NULL(clk->parents[i]))
-			if (clk->parents[i] == parent)
+			if (clk->parents[i] == newparent)
 				break;
 	}
 
 	if (i == clk->num_parents)
 		return -EINVAL;
 
-	return clk->ops->set_parent(clk, i);
+	if (clk->enable_count)
+		clk_enable(newparent);
+
+	ret = clk->ops->set_parent(clk, i);
+
+	if (clk->enable_count)
+		clk_disable(curparent);
+
+	return ret;
 }
 
 struct clk *clk_get_parent(struct clk *clk)
-- 
cgit v1.2.3


From bea07a688163c806a1001028f9eda715ca96976c Mon Sep 17 00:00:00 2001
From: Sascha Hauer <s.hauer@pengutronix.de>
Date: Wed, 1 Feb 2017 15:58:58 +0100
Subject: clk: implement CLK_OPS_PARENT_ENABLE

Some clocks may only be modified when their parent clocks are enabled.
The kernel has the CLK_OPS_PARENT_ENABLE flag for this purpose.
Implement it for barebox aswell.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 drivers/clk/clk.c   | 31 +++++++++++++++++++++++++++----
 include/linux/clk.h |  2 ++
 2 files changed, 29 insertions(+), 4 deletions(-)

(limited to 'drivers/clk/clk.c')

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 6f3053727c..93e000c6e9 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -141,6 +141,7 @@ int clk_set_rate(struct clk *clk, unsigned long rate)
 {
 	struct clk *parent;
 	unsigned long parent_rate = 0;
+	int ret;
 
 	if (!clk)
 		return 0;
@@ -148,14 +149,26 @@ int clk_set_rate(struct clk *clk, unsigned long rate)
 	if (IS_ERR(clk))
 		return PTR_ERR(clk);
 
+	if (!clk->ops->set_rate)
+		return -ENOSYS;
+
 	parent = clk_get_parent(clk);
-	if (parent)
+	if (parent) {
 		parent_rate = clk_get_rate(parent);
 
-	if (clk->ops->set_rate)
-		return clk->ops->set_rate(clk, rate, parent_rate);
+		if (clk->flags & CLK_OPS_PARENT_ENABLE) {
+			ret = clk_enable(parent);
+			if (ret)
+				return ret;
+		}
+	}
+
+	ret = clk->ops->set_rate(clk, rate, parent_rate);
+
+	if (parent && clk->flags & CLK_OPS_PARENT_ENABLE)
+		clk_disable(parent);
 
-	return -ENOSYS;
+	return ret;
 }
 
 struct clk *clk_lookup(const char *name)
@@ -203,8 +216,18 @@ int clk_set_parent(struct clk *clk, struct clk *newparent)
 	if (clk->enable_count)
 		clk_enable(newparent);
 
+	if (clk->flags & CLK_OPS_PARENT_ENABLE) {
+		clk_enable(curparent);
+		clk_enable(newparent);
+	}
+
 	ret = clk->ops->set_parent(clk, i);
 
+	if (clk->flags & CLK_OPS_PARENT_ENABLE) {
+		clk_disable(curparent);
+		clk_disable(newparent);
+	}
+
 	if (clk->enable_count)
 		clk_disable(curparent);
 
diff --git a/include/linux/clk.h b/include/linux/clk.h
index 8cb9731f12..697ab4ff4a 100644
--- a/include/linux/clk.h
+++ b/include/linux/clk.h
@@ -198,6 +198,8 @@ static inline int clk_set_rate(struct clk *clk, unsigned long rate)
 #ifdef CONFIG_COMMON_CLK
 
 #define CLK_SET_RATE_PARENT     (1 << 0) /* propagate rate change up one level */
+/* parents need enable during gate/ungate, set rate and re-parent */
+#define CLK_OPS_PARENT_ENABLE   (1 << 12)
 
 #define CLK_GATE_INVERTED	(1 << 0)
 #define CLK_GATE_HIWORD_MASK	(1 << 1)
-- 
cgit v1.2.3