[PATCH v6 03/10] clk: of-provider: look at parent if registered device has no provider info

Matti Vaittinen
2018-12-04T11:35:11Z

It seems to be usual for MFD devices that the created 'clock sub-device'
do not have own DT node. The clock provider information is usually in the
main device node which is owned by the MFD device. Change the devm variant
of clk of-provider registration to check the parent device node if given
device has no own node or if the node does not contain the #clock-cells
property. In such case use the parent node if it contains the #clock-cells.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
---
drivers/clk/clk.c | 27 +++++++++++++++++++++++----
1 file changed, 23 insertions(+), 4 deletions(-)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 78c90913f987..66dc7c1483d7 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -3893,6 +3893,11 @@ static void devm_of_clk_release_provider(struct device *dev, void *res)
of_clk_del_provider(*(struct device_node **)res);
}

+static int of_is_clk_provider(struct device_node *np)
+{
+ return !!of_find_property(np, "#clock-cells", NULL);
+}
+
/**
* devm_of_clk_add_hw_provider() - Managed clk provider node registration
* @dev: Device acting as the clock provider. Used for DT node and lifetime.
@@ -3901,8 +3906,11 @@ static void devm_of_clk_release_provider(struct device *dev, void *res)
*
* Returns 0 on success or an errno on failure.
*
- * Registers clock provider for given device's node. Provider is automatically
- * released at device exit.
+ * Registers clock provider for given device's node. If the device has no DT
+ * node or if the device node lacks of clock provider information (#clock-cells)
+ * then the parent device's node is scanned for this information. If parent node
+ * has the #clock-cells then it is used in registration. Provider is
+ * automatically released at device exit.
*/
int devm_of_clk_add_hw_provider(struct device *dev,
struct clk_hw *(*get)(struct of_phandle_args *clkspec,
@@ -3912,12 +3920,17 @@ int devm_of_clk_add_hw_provider(struct device *dev,
struct device_node **ptr, *np;
int ret;

+ np = dev->of_node;
+
+ if (!of_is_clk_provider(dev->of_node))
+ if (of_is_clk_provider(dev->parent->of_node))
+ np = dev->parent->of_node;
+
ptr = devres_alloc(devm_of_clk_release_provider, sizeof(*ptr),
GFP_KERNEL);
if (!ptr)
return -ENOMEM;

- np = dev->of_node;
ret = of_clk_add_hw_provider(np, get, data);
if (!ret) {
*ptr = np;
@@ -3968,9 +3981,15 @@ static int devm_clk_provider_match(struct device *dev, void *res, void *data)
void devm_of_clk_del_provider(struct device *dev)
{
int ret;
+ struct device_node *np;
+
+ np = dev->of_node;

+ if (!of_is_clk_provider(dev->of_node))
+ if (of_is_clk_provider(dev->parent->of_node))
+ np = dev->parent->of_node;
ret = devres_release(dev, devm_of_clk_release_provider,
- devm_clk_provider_match, dev->of_node);
+ devm_clk_provider_match, np);

WARN_ON(ret);
}
--
2.14.3