[RFC/PATCHv2 0/2] clk: of: add helper function to fill parent clock array

[RFC/PATCHv2 0/2] clk: of: add helper function to fill parent clock array

[dinguyen]

From: Dinh Nguyen <dinguyen@opensource.altera.com>

Hi,

As suggested by Stephen Boyd, this patch adds a helper function that will fill
the parent clock array.

Since the following code is sprinkled all over the platform clock drivers:

for (i = 0; i < num_parents; ++i)
        parent_names[i] = of_clk_get_parent_name(np, i);

The above code can be replace by of_clk_parent_fill(). And since the logic
of the of_clk_parent_fill is to walk the clock node to find the parent, it is
easy to just return the number of parents as well.

The second patch makes use of the new helper function in the SoCFPGA platform.
If this patch is accepted, I can go through and replace the other platforms
after that.

v2: use unsigned int for 'size'

Thanks,

Dinh Nguyen (2):
  clk: of: helper for filling parent clock array and return num of
    parents
  clk: socfpga: make use of of_clk_parent_fill helper function

 drivers/clk/clk.c              | 20 ++++++++++++++++++++
 drivers/clk/socfpga/clk-gate.c |  6 +-----
 drivers/clk/socfpga/clk-pll.c  |  7 +------
 include/linux/clk-provider.h   |  1 +
 4 files changed, 23 insertions(+), 11 deletions(-)

-- 
2.2.1

[RFC/PATCHv2 1/2] clk: of: helper for filling parent clock array and return num of parents

[dinguyen]

From: Dinh Nguyen <dinguyen@opensource.altera.com>

Sprinkled all through the platform clock drivers are code like this to
fill the clock parent array:

for (i = 0; i < num_parents; ++i)
	parent_names[i] = of_clk_get_parent_name(np, i);

The of_clk_parent_fill() will do the same as the code above, and while
at it, return the number of parents as well since the logic of the
function is to the walk the clock node to look for the parent.

Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
---
v2: use unsigned int for size
---
 drivers/clk/clk.c            | 20 ++++++++++++++++++++
 include/linux/clk-provider.h |  1 +
 2 files changed, 21 insertions(+)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 459ce9d..778bebd 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -3060,6 +3060,26 @@ const char *of_clk_get_parent_name(struct device_node *np, int index)
 }
 EXPORT_SYMBOL_GPL(of_clk_get_parent_name);
 
+/*
+ * of_clk_parent_fill(): Helper clock function that will fill the parent
+ * clock's array and return the number of parents it found.
+ * @np: Device node pointer associated with clock provider
+ * @parents: pointer to char array that hold the parent's name
+ * @size: size of the parents array
+ *
+ * Returns number of parents for the clock node.
+ */
+int of_clk_parent_fill(struct device_node *np, const char **parents, unsigned int size)
+{
+	unsigned int i = 0;
+
+	while (i < size && (parents[i] = of_clk_get_parent_name(np, i)) != NULL)
+		i++;
+
+	return i;
+}
+EXPORT_SYMBOL(of_clk_parent_fill);
+
 struct clock_provider {
 	of_clk_init_cb_t clk_init_cb;
 	struct device_node *np;
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index df69531..3ab66d3 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -624,6 +624,7 @@ struct clk *of_clk_src_simple_get(struct of_phandle_args *clkspec,
 				  void *data);
 struct clk *of_clk_src_onecell_get(struct of_phandle_args *clkspec, void *data);
 int of_clk_get_parent_count(struct device_node *np);
+int of_clk_parent_fill(struct device_node *np, const char **parents, unsigned int size);
 const char *of_clk_get_parent_name(struct device_node *np, int index);
 
 void of_clk_init(const struct of_device_id *matches);
-- 
2.2.1

[RFC/PATCHv2 2/2] clk: socfpga: make use of of_clk_parent_fill helper function

[dinguyen]

From: Dinh Nguyen <dinguyen@opensource.altera.com>

Use of_clk_parent_fill to fill in the parent clock's array.

Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
---
v2: none
---
 drivers/clk/socfpga/clk-gate.c | 6 +-----
 drivers/clk/socfpga/clk-pll.c  | 7 +------
 2 files changed, 2 insertions(+), 11 deletions(-)

diff --git a/drivers/clk/socfpga/clk-gate.c b/drivers/clk/socfpga/clk-gate.c
index dd3a78c..fb5a5d7 100644
--- a/drivers/clk/socfpga/clk-gate.c
+++ b/drivers/clk/socfpga/clk-gate.c
@@ -194,7 +194,6 @@ static void __init __socfpga_gate_init(struct device_node *node,
 	const char *parent_name[SOCFPGA_MAX_PARENTS];
 	struct clk_init_data init;
 	int rc;
-	int i = 0;
 
 	socfpga_clk = kzalloc(sizeof(*socfpga_clk), GFP_KERNEL);
 	if (WARN_ON(!socfpga_clk))
@@ -238,12 +237,9 @@ static void __init __socfpga_gate_init(struct device_node *node,
 	init.name = clk_name;
 	init.ops = ops;
 	init.flags = 0;
-	while (i < SOCFPGA_MAX_PARENTS && (parent_name[i] =
-			of_clk_get_parent_name(node, i)) != NULL)
-		i++;
 
+	init.num_parents = of_clk_parent_fill(node, parent_name, SOCFPGA_MAX_PARENTS);
 	init.parent_names = parent_name;
-	init.num_parents = i;
 	socfpga_clk->hw.hw.init = &init;
 
 	clk = clk_register(NULL, &socfpga_clk->hw.hw);
diff --git a/drivers/clk/socfpga/clk-pll.c b/drivers/clk/socfpga/clk-pll.c
index de6da95..8f26b52 100644
--- a/drivers/clk/socfpga/clk-pll.c
+++ b/drivers/clk/socfpga/clk-pll.c
@@ -92,7 +92,6 @@ static __init struct clk *__socfpga_pll_init(struct device_node *node,
 	struct clk_init_data init;
 	struct device_node *clkmgr_np;
 	int rc;
-	int i = 0;
 
 	of_property_read_u32(node, "reg", &reg);
 
@@ -111,11 +110,7 @@ static __init struct clk *__socfpga_pll_init(struct device_node *node,
 	init.ops = ops;
 	init.flags = 0;
 
-	while (i < SOCFPGA_MAX_PARENTS && (parent_name[i] =
-			of_clk_get_parent_name(node, i)) != NULL)
-		i++;
-
-	init.num_parents = i;
+	init.num_parents = of_clk_parent_fill(node, parent_name, SOCFPGA_MAX_PARENTS);
 	init.parent_names = parent_name;
 	pll_clk->hw.hw.init = &init;
 
-- 
2.2.1

Re: [RFC/PATCHv2 1/2] clk: of: helper for filling parent clock array and return num of parents

[Stephen Boyd]

On 06/04, dinguyen@opensource.altera.com wrote:
> From: Dinh Nguyen <dinguyen@opensource.altera.com>
> 
> Sprinkled all through the platform clock drivers are code like this to
> fill the clock parent array:
> 
> for (i = 0; i < num_parents; ++i)
> 	parent_names[i] = of_clk_get_parent_name(np, i);
> 
> The of_clk_parent_fill() will do the same as the code above, and while
> at it, return the number of parents as well since the logic of the
> function is to the walk the clock node to look for the parent.
> 
> Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
> ---
> v2: use unsigned int for size
> ---
>  drivers/clk/clk.c            | 20 ++++++++++++++++++++
>  include/linux/clk-provider.h |  1 +
>  2 files changed, 21 insertions(+)
> 
> diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
> index 459ce9d..778bebd 100644
> --- a/drivers/clk/clk.c
> +++ b/drivers/clk/clk.c
> @@ -3060,6 +3060,26 @@ const char *of_clk_get_parent_name(struct device_node *np, int index)
>  }
>  EXPORT_SYMBOL_GPL(of_clk_get_parent_name);
>  
> +/*

Need a double ** here for kernel doc.

> + * of_clk_parent_fill(): Helper clock function that will fill the parent
> + * clock's array and return the number of parents it found.

Please try to shorten this sentence.

	Fill @parents with names of @np's parents and return number of parents

> + * @np: Device node pointer associated with clock provider
> + * @parents: pointer to char array that hold the parent's name

s/parent's name/parents' names/ ?

> + * @size: size of the parents array
> + *
> + * Returns number of parents for the clock node.
> + */
> +int of_clk_parent_fill(struct device_node *np, const char **parents, unsigned int size)
> +{
> +	unsigned int i = 0;
> +
> +	while (i < size && (parents[i] = of_clk_get_parent_name(np, i)) != NULL)
> +		i++;
> +
> +	return i;
> +}
> +EXPORT_SYMBOL(of_clk_parent_fill);

Can this be GPL?

-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

Re: [RFC/PATCHv2 2/2] clk: socfpga: make use of of_clk_parent_fill helper function

[Stephen Boyd]

On 06/04, dinguyen@opensource.altera.com wrote:
> From: Dinh Nguyen <dinguyen@opensource.altera.com>
> 
> Use of_clk_parent_fill to fill in the parent clock's array.
> 
> Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
> ---
> v2: none
> ---
>  drivers/clk/socfpga/clk-gate.c | 6 +-----
>  drivers/clk/socfpga/clk-pll.c  | 7 +------
>  2 files changed, 2 insertions(+), 11 deletions(-)
> 

Nice consolidation!

-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

Re: [RFC/PATCHv2 1/2] clk: of: helper for filling parent clock array and return num of parents

[Dinh Nguyen]

On 6/4/15 4:24 PM, Stephen Boyd wrote:
> On 06/04, dinguyen@opensource.altera.com wrote:
>> From: Dinh Nguyen <dinguyen@opensource.altera.com>
>>
>> Sprinkled all through the platform clock drivers are code like this to
>> fill the clock parent array:
>>
>> for (i = 0; i < num_parents; ++i)
>> 	parent_names[i] = of_clk_get_parent_name(np, i);
>>
>> The of_clk_parent_fill() will do the same as the code above, and while
>> at it, return the number of parents as well since the logic of the
>> function is to the walk the clock node to look for the parent.
>>
>> Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
>> ---
>> v2: use unsigned int for size
>> ---
>>  drivers/clk/clk.c            | 20 ++++++++++++++++++++
>>  include/linux/clk-provider.h |  1 +
>>  2 files changed, 21 insertions(+)
>>
>> diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
>> index 459ce9d..778bebd 100644
>> --- a/drivers/clk/clk.c
>> +++ b/drivers/clk/clk.c
>> @@ -3060,6 +3060,26 @@ const char *of_clk_get_parent_name(struct device_node *np, int index)
>>  }
>>  EXPORT_SYMBOL_GPL(of_clk_get_parent_name);
>>  
>> +/*
> 
> Need a double ** here for kernel doc.
> 

Ok...

>> + * of_clk_parent_fill(): Helper clock function that will fill the parent
>> + * clock's array and return the number of parents it found.
> 
> Please try to shorten this sentence.
> 
> 	Fill @parents with names of @np's parents and return number of parents
> 
>> + * @np: Device node pointer associated with clock provider
>> + * @parents: pointer to char array that hold the parent's name
> 
> s/parent's name/parents' names/ ?
> 

Will address in v3.

>> + * @size: size of the parents array
>> + *
>> + * Returns number of parents for the clock node.
>> + */
>> +int of_clk_parent_fill(struct device_node *np, const char **parents, unsigned int size)
>> +{
>> +	unsigned int i = 0;
>> +
>> +	while (i < size && (parents[i] = of_clk_get_parent_name(np, i)) != NULL)
>> +		i++;
>> +
>> +	return i;
>> +}
>> +EXPORT_SYMBOL(of_clk_parent_fill);
> 
> Can this be GPL?
> 

Yes.

Thanks,
Dinh