[PATCH] clk: clk-gpio: Add dt option to propagate rate change to parent

[Alexandru Ardelean <alexandru.ardelean@analog.com>]

From: Michael Hennerich <michael.hennerich@analog.com>

For certain setups/boards it's useful to propagate the rate change of the
clock up one level to the parent clock.

This change implements this by defining a `clk-set-rate-parent` device-tree
property which sets the `CLK_SET_RATE_PARENT` flag to the clock (when set).

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
---
 drivers/clk/clk-gpio.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/clk-gpio.c b/drivers/clk/clk-gpio.c
index 9d930edd6516..6dfbc4b952fe 100644
--- a/drivers/clk/clk-gpio.c
+++ b/drivers/clk/clk-gpio.c
@@ -241,6 +241,7 @@ static int gpio_clk_driver_probe(struct platform_device *pdev)
 	struct device_node *node = pdev->dev.of_node;
 	const char **parent_names, *gpio_name;
 	unsigned int num_parents;
+	unsigned long clk_flags;
 	struct gpio_desc *gpiod;
 	struct clk *clk;
 	bool is_mux;
@@ -274,13 +275,16 @@ static int gpio_clk_driver_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	clk_flags = of_property_read_bool(node, "clk-set-rate-parent") ?
+			CLK_SET_RATE_PARENT : 0;
+
 	if (is_mux)
 		clk = clk_register_gpio_mux(&pdev->dev, node->name,
-				parent_names, num_parents, gpiod, 0);
+				parent_names, num_parents, gpiod, clk_flags);
 	else
 		clk = clk_register_gpio_gate(&pdev->dev, node->name,
 				parent_names ?  parent_names[0] : NULL, gpiod,
-				0);
+				clk_flags);
 	if (IS_ERR(clk))
 		return PTR_ERR(clk);
 
-- 
2.20.1