[PATCH v2] clk: add device tree fixed-factor-clock binding support

[Gregory CLEMENT]

On 04/12/2013 12:30 PM, Christian Ruppert wrote:
> Hi Gregory,
> 
> Just tested the patch and it works perfectly. Did you forget to update
> Documentation/devicetree/bindings/clock/fixed-factor-clock.txt, however?

Oh yes you're right. I will send a v3 with this modification.
Can I also add your tested-by flag?

Thanks,


> 
> Greetings,
>   Christian
> 
> On Fri, Apr 12, 2013 at 11:58:28AM +0200, Gregory CLEMENT wrote:
>> Add support for DT "fixed-factor-clock" binding to the common fixed
>> factor clock support.
>>
>> Signed-off-by: Gregory CLEMENT <gregory.clement at free-electrons.com>
>> ---
>>  .../bindings/clock/fixed-factor-clock.txt          |   24 +++++++++++++
>>  drivers/clk/clk-fixed-factor.c                     |   36 ++++++++++++++++++++
>>  include/linux/clk-provider.h                       |    2 ++
>>  3 files changed, 62 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/clock/fixed-factor-clock.txt
>>
>> diff --git a/Documentation/devicetree/bindings/clock/fixed-factor-clock.txt b/Documentation/devicetree/bindings/clock/fixed-factor-clock.txt
>> new file mode 100644
>> index 0000000..7ed236f
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/clock/fixed-factor-clock.txt
>> @@ -0,0 +1,24 @@
>> +Binding for simple fixed factor rate clock sources.
>> +
>> +This binding uses the common clock binding[1].
>> +
>> +[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
>> +
>> +Required properties:
>> +- compatible : shall be "fixed-factor-clock".
>> +- #clock-cells : from common clock binding; shall be set to 0.
>> +- div: fixed divider.
>> +- mult: fixed multiplier.
>> +- clocks: parent clock.
>> +
>> +Optional properties:
>> +- clock-output-names : From common clock binding.
>> +
>> +Example:
>> +	clock {
>> +		compatible = "fixed-factor-clock";
>> +		clocks = <&parentclk>;
>> +		#clock-cells = <0>;
>> +		div = <2>;
>> +		mult = <1>;
>> +	};
>> diff --git a/drivers/clk/clk-fixed-factor.c b/drivers/clk/clk-fixed-factor.c
>> index 1ef271e..9ff7d51 100644
>> --- a/drivers/clk/clk-fixed-factor.c
>> +++ b/drivers/clk/clk-fixed-factor.c
>> @@ -11,6 +11,7 @@
>>  #include <linux/clk-provider.h>
>>  #include <linux/slab.h>
>>  #include <linux/err.h>
>> +#include <linux/of.h>
>>  
>>  /*
>>   * DOC: basic fixed multiplier and divider clock that cannot gate
>> @@ -96,3 +97,38 @@ struct clk *clk_register_fixed_factor(struct device *dev, const char *name,
>>  
>>  	return clk;
>>  }
>> +#ifdef CONFIG_OF
>> +/**
>> + * of_fixed_factor_clk_setup() - Setup function for simple fixed factor clock
>> + */
>> +void __init of_fixed_factor_clk_setup(struct device_node *node)
>> +{
>> +	struct clk *clk;
>> +	const char *clk_name = node->name;
>> +	const char *parent_name;
>> +	u32 div, mult;
>> +
>> +	if (of_property_read_u32(node, "clock-div", &div)) {
>> +		pr_err("%s Fixed factor clock <%s> must have a clock-div property\n",
>> +			__func__, node->name);
>> +		return;
>> +	}
>> +
>> +	if (of_property_read_u32(node, "clock-mult", &mult)) {
>> +		pr_err("%s Fixed factor clock <%s> must have a clokc-mult property\n",
>> +			__func__, node->name);
>> +		return;
>> +	}
>> +
>> +	of_property_read_string(node, "clock-output-names", &clk_name);
>> +	parent_name = of_clk_get_parent_name(node, 0);
>> +
>> +	clk = clk_register_fixed_factor(NULL, clk_name, parent_name, 0,
>> +					mult, div);
>> +	if (!IS_ERR(clk))
>> +		of_clk_add_provider(node, of_clk_src_simple_get, clk);
>> +}
>> +EXPORT_SYMBOL_GPL(of_fixed_factor_clk_setup);
>> +CLK_OF_DECLARE(fixed_factor_clk, "fixed-factor-clock",
>> +		of_fixed_factor_clk_setup);
>> +#endif
>> diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
>> index 7f197d7..7ea501b 100644
>> --- a/include/linux/clk-provider.h
>> +++ b/include/linux/clk-provider.h
>> @@ -325,6 +325,8 @@ struct clk *clk_register_fixed_factor(struct device *dev, const char *name,
>>  		const char *parent_name, unsigned long flags,
>>  		unsigned int mult, unsigned int div);
>>  
>> +void of_fixed_factor_clk_setup(struct device_node *node);
>> +
>>  /**
>>   * clk_register - allocate a new clock, register it and return an opaque cookie
>>   * @dev: device that is registering this clock
>> -- 
>> 1.7.9.5
>>
> 


-- 
Gregory Clement, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com