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[v2,00/11] PM / devfreq: Remove deprecated 'devfreq' and 'devfreq-events' properties

Message ID 20191220002430.11995-1-cw00.choi@samsung.com
Headers show
Series PM / devfreq: Remove deprecated 'devfreq' and 'devfreq-events' properties | expand

Message

Chanwoo Choi Dec. 20, 2019, 12:24 a.m. UTC
From: Chanwoo Choi <cw00.choi@samsun.com>

The devfreq and devfreq-event subsystem provided the following two properties:
- Provide 'devfreq' property in order to get the parent devfreq device
  by devfreq_get_devfreq_by_phandle() if devfreq device use passive governor.
- Provide 'devfreq-events' property in order to get the devfreq-event device
  by devfreq_event_get_edev_by_phandle().

But, two properties name is not proper expressing the h/w
and 'devfreq' word is name of linux subsystem instead of any h/w name.

Hand over the rights for deciding the property name for getting
the devfreq/devfreq-event device on devicetree, to each devfreq driver.

So, replace 'devfreq' and 'devfreq-events' property with following property
name according to each devfreq driver:
--------------------------------------------------------------------
Old property  | New property       | Device driver name            |
--------------------------------------------------------------------
devfreq       | exynos,parent-bus  | exynos-bus.c                  |
              |                    |                               |
devfreq-events| exynos,ppmu-device | exynos-bus.c, exynos5422-dmc.c|
              | rockchip,dfi-device| rk3399_dmc.c                  |
--------------------------------------------------------------------

Changes from v1:
- Edit function name by removing '_by_node' postfix.
- Split out dt-binding patch to make it the separte patch.j
- Add Lukasz's tag for exynos5422-dmc

Chanwoo Choi (10):
  PM / devfreq: Remove devfreq_get_devfreq_by_phandle function
  PM / devfreq: event: Add devfreq_event_get_edev_by_node function
  dt-bindings: devfreq: exynos-bus: Replace deprecated 'devfreq' and 'devfreq-events' property
  dt-bindings: devfreq: rk3399_dmc:  Replace deprecated 'devfreq-events' property
  dt-bindings: memory: exynos5422-dmc: Replace the deprecated 'devfreq-events' property
  PM / devfreq: exynos-bus: Replace the deprecated 'devfreq' and 'devfreq-events' property
  PM / devfreq: rk3399_dmc: Replace the deprecated 'devfreq-events' property
  memory: samsung: exynos5422-dmc: Replace the deprecated 'devfreq-events' property
  ARM: dts: exynos: Replace deprecated property for Exynos bus and DMC
  arm64: dts: exynos: Replace deprecated property for Exynos bus on TM2

Leonard Crestez (1):
  PM / devfreq: Add devfreq_get_devfreq_by_node function

 .../bindings/devfreq/exynos-bus.txt           | 22 +++----
 .../bindings/devfreq/rk3399_dmc.txt           |  4 +-
 .../memory-controllers/exynos5422-dmc.txt     |  8 +--
 arch/arm/boot/dts/exynos3250-monk.dts         |  2 +-
 arch/arm/boot/dts/exynos3250-rinato.dts       | 18 +++---
 .../boot/dts/exynos4412-itop-scp-core.dtsi    | 16 ++---
 arch/arm/boot/dts/exynos4412-midas.dtsi       | 18 +++---
 .../boot/dts/exynos4412-odroid-common.dtsi    | 18 +++---
 arch/arm/boot/dts/exynos5422-odroid-core.dtsi | 34 +++++------
 .../dts/exynos/exynos5433-tm2-common.dtsi     | 20 +++----
 drivers/devfreq/devfreq-event.c               | 53 +++--------------
 drivers/devfreq/devfreq.c                     | 25 +++-----
 drivers/devfreq/exynos-bus.c                  | 58 ++++++++++++++++---
 drivers/devfreq/rk3399_dmc.c                  | 16 ++++-
 drivers/memory/samsung/exynos5422-dmc.c       | 37 ++++++++++--
 include/linux/devfreq-event.h                 | 14 ++---
 include/linux/devfreq.h                       |  6 +-
 17 files changed, 198 insertions(+), 171 deletions(-)

Comments

Leonard Crestez Dec. 20, 2019, 12:46 a.m. UTC | #1
On 20.12.2019 02:18, Chanwoo Choi wrote:
> Previously, devfreq core support 'devfreq' property in order to get
> the devfreq device by phandle. But, 'devfreq' property name is not proper
> on devicetree binding because this name doesn't mean the any h/w attribute.
> 
> The devfreq core hand over the right to decide the property name
> for getting the devfreq device on devicetree. Each devfreq driver
> will decide the property name on devicetree binding and then get
> the devfreq device by using devfreq_get_devfreq_by_node().
> 
> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
> ---
>   drivers/devfreq/devfreq.c    | 35 -----------------------------------
>   drivers/devfreq/exynos-bus.c | 12 +++++++++++-
>   include/linux/devfreq.h      |  8 --------
>   3 files changed, 11 insertions(+), 44 deletions(-)
> 
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index cb8ca81c8973..c3d3c7c802a0 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -991,48 +991,13 @@ struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
>   
>   	return ERR_PTR(-ENODEV);
>   }
> -
> -/*
> - * devfreq_get_devfreq_by_phandle - Get the devfreq device from devicetree
> - * @dev - instance to the given device
> - * @index - index into list of devfreq
> - *
> - * return the instance of devfreq device
> - */
> -struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
> -{
> -	struct device_node *node;
> -	struct devfreq *devfreq;
> -
> -	if (!dev)
> -		return ERR_PTR(-EINVAL);
> -
> -	if (!dev->of_node)
> -		return ERR_PTR(-EINVAL);
> -
> -	node = of_parse_phandle(dev->of_node, "devfreq", index);
> -	if (!node)
> -		return ERR_PTR(-ENODEV);
> -
> -	devfreq = devfreq_get_devfreq_by_node(node);
> -	of_node_put(node);
> -
> -	return devfreq;
> -}
> -
>   #else
>   struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
>   {
>   	return ERR_PTR(-ENODEV);
>   }
> -
> -struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
> -{
> -	return ERR_PTR(-ENODEV);
> -}
>   #endif /* CONFIG_OF */
>   EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_node);
> -EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_phandle);
>   
>   /**
>    * devm_devfreq_remove_device() - Resource-managed devfreq_remove_device()
> diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
> index 7f5917d59072..1bc4e3c81115 100644
> --- a/drivers/devfreq/exynos-bus.c
> +++ b/drivers/devfreq/exynos-bus.c
> @@ -86,6 +86,16 @@ static int exynos_bus_get_event(struct exynos_bus *bus,
>   	return ret;
>   }
>   
> +static struct devfreq *exynos_bus_get_parent_devfreq(struct device_node *np)
> +{
> +	struct device_node *node = of_parse_phandle(np, "devfreq", 0);
> +
> +	if (!node)
> +		return ERR_PTR(-ENODEV);
> +
> +	return devfreq_get_devfreq_by_node(node);

You need to call of_node_put(node) here and in several other places.

The old devfreq_get_devfreq_by_phandle API handled this internally but 
devfreq_get_devfreq_by_node doesn't.

Maybe the _by_phandle API could be kept and just take the property name 
instead of always using "devfreq"?

> +}
> +
>   /*
>    * devfreq function for both simple-ondemand and passive governor
>    */
> @@ -353,7 +363,7 @@ static int exynos_bus_profile_init_passive(struct exynos_bus *bus,
>   	profile->exit = exynos_bus_passive_exit;
>   
>   	/* Get the instance of parent devfreq device */
> -	parent_devfreq = devfreq_get_devfreq_by_phandle(dev, 0);
> +	parent_devfreq = exynos_bus_get_parent_devfreq(dev->of_node);
>   	if (IS_ERR(parent_devfreq))
>   		return -EPROBE_DEFER;
>   
> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
> index 1dccc47acbce..a4351698fb64 100644
> --- a/include/linux/devfreq.h
> +++ b/include/linux/devfreq.h
> @@ -254,8 +254,6 @@ extern void devm_devfreq_unregister_notifier(struct device *dev,
>   				struct notifier_block *nb,
>   				unsigned int list);
>   extern struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node);
> -extern struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev,
> -						int index);
>   
>   #if IS_ENABLED(CONFIG_DEVFREQ_GOV_SIMPLE_ONDEMAND)
>   /**
> @@ -413,12 +411,6 @@ static inline struct devfreq *devfreq_get_devfreq_by_node(struct device_node *no
>   	return ERR_PTR(-ENODEV);
>   }
>   
> -static inline struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev,
> -							int index)
> -{
> -	return ERR_PTR(-ENODEV);
> -}
> -
>   static inline int devfreq_update_stats(struct devfreq *df)
>   {
>   	return -EINVAL;
>
Chanwoo Choi Dec. 20, 2019, 1 a.m. UTC | #2
On 12/20/19 9:46 AM, Leonard Crestez wrote:
> On 20.12.2019 02:18, Chanwoo Choi wrote:
>> Previously, devfreq core support 'devfreq' property in order to get
>> the devfreq device by phandle. But, 'devfreq' property name is not proper
>> on devicetree binding because this name doesn't mean the any h/w attribute.
>>
>> The devfreq core hand over the right to decide the property name
>> for getting the devfreq device on devicetree. Each devfreq driver
>> will decide the property name on devicetree binding and then get
>> the devfreq device by using devfreq_get_devfreq_by_node().
>>
>> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
>> ---
>>   drivers/devfreq/devfreq.c    | 35 -----------------------------------
>>   drivers/devfreq/exynos-bus.c | 12 +++++++++++-
>>   include/linux/devfreq.h      |  8 --------
>>   3 files changed, 11 insertions(+), 44 deletions(-)
>>
>> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
>> index cb8ca81c8973..c3d3c7c802a0 100644
>> --- a/drivers/devfreq/devfreq.c
>> +++ b/drivers/devfreq/devfreq.c
>> @@ -991,48 +991,13 @@ struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
>>   
>>   	return ERR_PTR(-ENODEV);
>>   }
>> -
>> -/*
>> - * devfreq_get_devfreq_by_phandle - Get the devfreq device from devicetree
>> - * @dev - instance to the given device
>> - * @index - index into list of devfreq
>> - *
>> - * return the instance of devfreq device
>> - */
>> -struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
>> -{
>> -	struct device_node *node;
>> -	struct devfreq *devfreq;
>> -
>> -	if (!dev)
>> -		return ERR_PTR(-EINVAL);
>> -
>> -	if (!dev->of_node)
>> -		return ERR_PTR(-EINVAL);
>> -
>> -	node = of_parse_phandle(dev->of_node, "devfreq", index);
>> -	if (!node)
>> -		return ERR_PTR(-ENODEV);
>> -
>> -	devfreq = devfreq_get_devfreq_by_node(node);
>> -	of_node_put(node);
>> -
>> -	return devfreq;
>> -}
>> -
>>   #else
>>   struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
>>   {
>>   	return ERR_PTR(-ENODEV);
>>   }
>> -
>> -struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
>> -{
>> -	return ERR_PTR(-ENODEV);
>> -}
>>   #endif /* CONFIG_OF */
>>   EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_node);
>> -EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_phandle);
>>   
>>   /**
>>    * devm_devfreq_remove_device() - Resource-managed devfreq_remove_device()
>> diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
>> index 7f5917d59072..1bc4e3c81115 100644
>> --- a/drivers/devfreq/exynos-bus.c
>> +++ b/drivers/devfreq/exynos-bus.c
>> @@ -86,6 +86,16 @@ static int exynos_bus_get_event(struct exynos_bus *bus,
>>   	return ret;
>>   }
>>   
>> +static struct devfreq *exynos_bus_get_parent_devfreq(struct device_node *np)
>> +{
>> +	struct device_node *node = of_parse_phandle(np, "devfreq", 0);
>> +
>> +	if (!node)
>> +		return ERR_PTR(-ENODEV);
>> +
>> +	return devfreq_get_devfreq_by_node(node);
> 
> You need to call of_node_put(node) here and in several other places.
> 
> The old devfreq_get_devfreq_by_phandle API handled this internally but 
> devfreq_get_devfreq_by_node doesn't.

Thanks. I'll fix it.

> 
> Maybe the _by_phandle API could be kept and just take the property name 
> instead of always using "devfreq"?

Do you mean like below?
devfreq_get_devfreq_by_phandle(struct device *dev, int index)
-> devfreq_get_devfreq_by_phandle(struct device *dev, char *property_name, int index)

In case of devfreq-event.c,
struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(
						struct device *dev,
						char property_name,
						int index)
int devfreq_event_get_edev_count(struct device *dev, char *property_name)

> 
>> +}
>> +
>>   /*
>>    * devfreq function for both simple-ondemand and passive governor
>>    */
>> @@ -353,7 +363,7 @@ static int exynos_bus_profile_init_passive(struct exynos_bus *bus,
>>   	profile->exit = exynos_bus_passive_exit;
>>   
>>   	/* Get the instance of parent devfreq device */
>> -	parent_devfreq = devfreq_get_devfreq_by_phandle(dev, 0);
>> +	parent_devfreq = exynos_bus_get_parent_devfreq(dev->of_node);
>>   	if (IS_ERR(parent_devfreq))
>>   		return -EPROBE_DEFER;
>>   
>> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
>> index 1dccc47acbce..a4351698fb64 100644
>> --- a/include/linux/devfreq.h
>> +++ b/include/linux/devfreq.h
>> @@ -254,8 +254,6 @@ extern void devm_devfreq_unregister_notifier(struct device *dev,
>>   				struct notifier_block *nb,
>>   				unsigned int list);
>>   extern struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node);
>> -extern struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev,
>> -						int index);
>>   
>>   #if IS_ENABLED(CONFIG_DEVFREQ_GOV_SIMPLE_ONDEMAND)
>>   /**
>> @@ -413,12 +411,6 @@ static inline struct devfreq *devfreq_get_devfreq_by_node(struct device_node *no
>>   	return ERR_PTR(-ENODEV);
>>   }
>>   
>> -static inline struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev,
>> -							int index)
>> -{
>> -	return ERR_PTR(-ENODEV);
>> -}
>> -
>>   static inline int devfreq_update_stats(struct devfreq *df)
>>   {
>>   	return -EINVAL;
>>
> 
> 
>
Leonard Crestez Dec. 20, 2019, 1:40 a.m. UTC | #3
On 2019-12-20 2:54 AM, Chanwoo Choi wrote:
> On 12/20/19 9:46 AM, Leonard Crestez wrote:
>> On 20.12.2019 02:18, Chanwoo Choi wrote:
>>> Previously, devfreq core support 'devfreq' property in order to get
>>> the devfreq device by phandle. But, 'devfreq' property name is not proper
>>> on devicetree binding because this name doesn't mean the any h/w attribute.
>>>
>>> The devfreq core hand over the right to decide the property name
>>> for getting the devfreq device on devicetree. Each devfreq driver
>>> will decide the property name on devicetree binding and then get
>>> the devfreq device by using devfreq_get_devfreq_by_node().
>>>
>>> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
>>> ---
>>>    drivers/devfreq/devfreq.c    | 35 -----------------------------------
>>>    drivers/devfreq/exynos-bus.c | 12 +++++++++++-
>>>    include/linux/devfreq.h      |  8 --------
>>>    3 files changed, 11 insertions(+), 44 deletions(-)
>>>
>>> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
>>> index cb8ca81c8973..c3d3c7c802a0 100644
>>> --- a/drivers/devfreq/devfreq.c
>>> +++ b/drivers/devfreq/devfreq.c
>>> @@ -991,48 +991,13 @@ struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
>>>    
>>>    	return ERR_PTR(-ENODEV);
>>>    }
>>> -
>>> -/*
>>> - * devfreq_get_devfreq_by_phandle - Get the devfreq device from devicetree
>>> - * @dev - instance to the given device
>>> - * @index - index into list of devfreq
>>> - *
>>> - * return the instance of devfreq device
>>> - */
>>> -struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
>>> -{
>>> -	struct device_node *node;
>>> -	struct devfreq *devfreq;
>>> -
>>> -	if (!dev)
>>> -		return ERR_PTR(-EINVAL);
>>> -
>>> -	if (!dev->of_node)
>>> -		return ERR_PTR(-EINVAL);
>>> -
>>> -	node = of_parse_phandle(dev->of_node, "devfreq", index);
>>> -	if (!node)
>>> -		return ERR_PTR(-ENODEV);
>>> -
>>> -	devfreq = devfreq_get_devfreq_by_node(node);
>>> -	of_node_put(node);
>>> -
>>> -	return devfreq;
>>> -}
>>> -
>>>    #else
>>>    struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
>>>    {
>>>    	return ERR_PTR(-ENODEV);
>>>    }
>>> -
>>> -struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
>>> -{
>>> -	return ERR_PTR(-ENODEV);
>>> -}
>>>    #endif /* CONFIG_OF */
>>>    EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_node);
>>> -EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_phandle);
>>>    
>>>    /**
>>>     * devm_devfreq_remove_device() - Resource-managed devfreq_remove_device()
>>> diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
>>> index 7f5917d59072..1bc4e3c81115 100644
>>> --- a/drivers/devfreq/exynos-bus.c
>>> +++ b/drivers/devfreq/exynos-bus.c
>>> @@ -86,6 +86,16 @@ static int exynos_bus_get_event(struct exynos_bus *bus,
>>>    	return ret;
>>>    }
>>>    
>>> +static struct devfreq *exynos_bus_get_parent_devfreq(struct device_node *np)
>>> +{
>>> +	struct device_node *node = of_parse_phandle(np, "devfreq", 0);
>>> +
>>> +	if (!node)
>>> +		return ERR_PTR(-ENODEV);
>>> +
>>> +	return devfreq_get_devfreq_by_node(node);
>>
>> You need to call of_node_put(node) here and in several other places.
>>
>> The old devfreq_get_devfreq_by_phandle API handled this internally but
>> devfreq_get_devfreq_by_node doesn't.
> 
> Thanks. I'll fix it.
> 
>>
>> Maybe the _by_phandle API could be kept and just take the property name
>> instead of always using "devfreq"?
> 
> Do you mean like below?
> devfreq_get_devfreq_by_phandle(struct device *dev, int index)
> -> devfreq_get_devfreq_by_phandle(struct device *dev, char *property_name, int index)
> 
> In case of devfreq-event.c,
> struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(
> 						struct device *dev,
> 						char property_name,
> 						int index)
> int devfreq_event_get_edev_count(struct device *dev, char *property_name)

Yes. These helpers would avoid the need for explicit of_node_put.

> 
>>
>>> +}
>>> +
>>>    /*
>>>     * devfreq function for both simple-ondemand and passive governor
>>>     */
>>> @@ -353,7 +363,7 @@ static int exynos_bus_profile_init_passive(struct exynos_bus *bus,
>>>    	profile->exit = exynos_bus_passive_exit;
>>>    
>>>    	/* Get the instance of parent devfreq device */
>>> -	parent_devfreq = devfreq_get_devfreq_by_phandle(dev, 0);
>>> +	parent_devfreq = exynos_bus_get_parent_devfreq(dev->of_node);
>>>    	if (IS_ERR(parent_devfreq))
>>>    		return -EPROBE_DEFER;
>>>    
>>> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
>>> index 1dccc47acbce..a4351698fb64 100644
>>> --- a/include/linux/devfreq.h
>>> +++ b/include/linux/devfreq.h
>>> @@ -254,8 +254,6 @@ extern void devm_devfreq_unregister_notifier(struct device *dev,
>>>    				struct notifier_block *nb,
>>>    				unsigned int list);
>>>    extern struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node);
>>> -extern struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev,
>>> -						int index);
>>>    
>>>    #if IS_ENABLED(CONFIG_DEVFREQ_GOV_SIMPLE_ONDEMAND)
>>>    /**
>>> @@ -413,12 +411,6 @@ static inline struct devfreq *devfreq_get_devfreq_by_node(struct device_node *no
>>>    	return ERR_PTR(-ENODEV);
>>>    }
>>>    
>>> -static inline struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev,
>>> -							int index)
>>> -{
>>> -	return ERR_PTR(-ENODEV);
>>> -}
>>> -
>>>    static inline int devfreq_update_stats(struct devfreq *df)
>>>    {
>>>    	return -EINVAL;
Chanwoo Choi Dec. 20, 2019, 2:14 a.m. UTC | #4
On 12/20/19 10:40 AM, Leonard Crestez wrote:
> On 2019-12-20 2:54 AM, Chanwoo Choi wrote:
>> On 12/20/19 9:46 AM, Leonard Crestez wrote:
>>> On 20.12.2019 02:18, Chanwoo Choi wrote:
>>>> Previously, devfreq core support 'devfreq' property in order to get
>>>> the devfreq device by phandle. But, 'devfreq' property name is not proper
>>>> on devicetree binding because this name doesn't mean the any h/w attribute.
>>>>
>>>> The devfreq core hand over the right to decide the property name
>>>> for getting the devfreq device on devicetree. Each devfreq driver
>>>> will decide the property name on devicetree binding and then get
>>>> the devfreq device by using devfreq_get_devfreq_by_node().
>>>>
>>>> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
>>>> ---
>>>>    drivers/devfreq/devfreq.c    | 35 -----------------------------------
>>>>    drivers/devfreq/exynos-bus.c | 12 +++++++++++-
>>>>    include/linux/devfreq.h      |  8 --------
>>>>    3 files changed, 11 insertions(+), 44 deletions(-)
>>>>
>>>> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
>>>> index cb8ca81c8973..c3d3c7c802a0 100644
>>>> --- a/drivers/devfreq/devfreq.c
>>>> +++ b/drivers/devfreq/devfreq.c
>>>> @@ -991,48 +991,13 @@ struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
>>>>    
>>>>    	return ERR_PTR(-ENODEV);
>>>>    }
>>>> -
>>>> -/*
>>>> - * devfreq_get_devfreq_by_phandle - Get the devfreq device from devicetree
>>>> - * @dev - instance to the given device
>>>> - * @index - index into list of devfreq
>>>> - *
>>>> - * return the instance of devfreq device
>>>> - */
>>>> -struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
>>>> -{
>>>> -	struct device_node *node;
>>>> -	struct devfreq *devfreq;
>>>> -
>>>> -	if (!dev)
>>>> -		return ERR_PTR(-EINVAL);
>>>> -
>>>> -	if (!dev->of_node)
>>>> -		return ERR_PTR(-EINVAL);
>>>> -
>>>> -	node = of_parse_phandle(dev->of_node, "devfreq", index);
>>>> -	if (!node)
>>>> -		return ERR_PTR(-ENODEV);
>>>> -
>>>> -	devfreq = devfreq_get_devfreq_by_node(node);
>>>> -	of_node_put(node);
>>>> -
>>>> -	return devfreq;
>>>> -}
>>>> -
>>>>    #else
>>>>    struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
>>>>    {
>>>>    	return ERR_PTR(-ENODEV);
>>>>    }
>>>> -
>>>> -struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
>>>> -{
>>>> -	return ERR_PTR(-ENODEV);
>>>> -}
>>>>    #endif /* CONFIG_OF */
>>>>    EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_node);
>>>> -EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_phandle);
>>>>    
>>>>    /**
>>>>     * devm_devfreq_remove_device() - Resource-managed devfreq_remove_device()
>>>> diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
>>>> index 7f5917d59072..1bc4e3c81115 100644
>>>> --- a/drivers/devfreq/exynos-bus.c
>>>> +++ b/drivers/devfreq/exynos-bus.c
>>>> @@ -86,6 +86,16 @@ static int exynos_bus_get_event(struct exynos_bus *bus,
>>>>    	return ret;
>>>>    }
>>>>    
>>>> +static struct devfreq *exynos_bus_get_parent_devfreq(struct device_node *np)
>>>> +{
>>>> +	struct device_node *node = of_parse_phandle(np, "devfreq", 0);
>>>> +
>>>> +	if (!node)
>>>> +		return ERR_PTR(-ENODEV);
>>>> +
>>>> +	return devfreq_get_devfreq_by_node(node);
>>>
>>> You need to call of_node_put(node) here and in several other places.
>>>
>>> The old devfreq_get_devfreq_by_phandle API handled this internally but
>>> devfreq_get_devfreq_by_node doesn't.
>>
>> Thanks. I'll fix it.
>>
>>>
>>> Maybe the _by_phandle API could be kept and just take the property name
>>> instead of always using "devfreq"?
>>
>> Do you mean like below?
>> devfreq_get_devfreq_by_phandle(struct device *dev, int index)
>> -> devfreq_get_devfreq_by_phandle(struct device *dev, char *property_name, int index)
>>
>> In case of devfreq-event.c,
>> struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(
>> 						struct device *dev,
>> 						char property_name,
>> 						int index)
>> int devfreq_event_get_edev_count(struct device *dev, char *property_name)
> 
> Yes. These helpers would avoid the need for explicit of_node_put.

OK. Instead of removing devfreq_event_get_edev_by_phandle,
change the function property of devfreq_event_get_edev_by_phandle on v3.

After getting the review for dt-binding patch, I'll send v3 patches.

> 
>>
>>>
>>>> +}
>>>> +
>>>>    /*
>>>>     * devfreq function for both simple-ondemand and passive governor
>>>>     */
>>>> @@ -353,7 +363,7 @@ static int exynos_bus_profile_init_passive(struct exynos_bus *bus,
>>>>    	profile->exit = exynos_bus_passive_exit;
>>>>    
>>>>    	/* Get the instance of parent devfreq device */
>>>> -	parent_devfreq = devfreq_get_devfreq_by_phandle(dev, 0);
>>>> +	parent_devfreq = exynos_bus_get_parent_devfreq(dev->of_node);
>>>>    	if (IS_ERR(parent_devfreq))
>>>>    		return -EPROBE_DEFER;
>>>>    
>>>> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
>>>> index 1dccc47acbce..a4351698fb64 100644
>>>> --- a/include/linux/devfreq.h
>>>> +++ b/include/linux/devfreq.h
>>>> @@ -254,8 +254,6 @@ extern void devm_devfreq_unregister_notifier(struct device *dev,
>>>>    				struct notifier_block *nb,
>>>>    				unsigned int list);
>>>>    extern struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node);
>>>> -extern struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev,
>>>> -						int index);
>>>>    
>>>>    #if IS_ENABLED(CONFIG_DEVFREQ_GOV_SIMPLE_ONDEMAND)
>>>>    /**
>>>> @@ -413,12 +411,6 @@ static inline struct devfreq *devfreq_get_devfreq_by_node(struct device_node *no
>>>>    	return ERR_PTR(-ENODEV);
>>>>    }
>>>>    
>>>> -static inline struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev,
>>>> -							int index)
>>>> -{
>>>> -	return ERR_PTR(-ENODEV);
>>>> -}
>>>> -
>>>>    static inline int devfreq_update_stats(struct devfreq *df)
>>>>    {
>>>>    	return -EINVAL;
> 
> 
>
Lukasz Luba Jan. 9, 2020, 9:47 a.m. UTC | #5
Hi Chanwoo,


On 12/20/19 12:24 AM, Chanwoo Choi wrote:
> From: Leonard Crestez <leonard.crestez@nxp.com>
> 
> Split off part of devfreq_get_devfreq_by_phandle into a separate
> function. This allows callers to fetch devfreq instances by enumerating
> devicetree instead of explicit phandles.
> 
> [lkp: Reported the build error]
> Reported-by: kbuild test robot <lkp@intel.com>
> Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
> [cw00.choi: Export devfreq_get_devfreq_by_node function and
>   add function to devfreq.h when CONFIG_PM_DEVFREQ is enabled.]
> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
> ---
>   drivers/devfreq/devfreq.c | 46 +++++++++++++++++++++++++++++----------
>   include/linux/devfreq.h   |  6 +++++
>   2 files changed, 41 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index 89260b17598f..cb8ca81c8973 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -966,6 +966,32 @@ struct devfreq *devm_devfreq_add_device(struct device *dev,
>   EXPORT_SYMBOL(devm_devfreq_add_device);
>   
>   #ifdef CONFIG_OF
> +/*
> + * devfreq_get_devfreq_by_node - Get the devfreq device from devicetree
> + * @node - pointer to device_node
> + *
> + * return the instance of devfreq device
> + */
> +struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
> +{
> +	struct devfreq *devfreq;
> +
> +	if (!node)
> +		return ERR_PTR(-EINVAL);
> +
> +	mutex_lock(&devfreq_list_lock);
> +	list_for_each_entry(devfreq, &devfreq_list, node) {
> +		if (devfreq->dev.parent
> +			&& devfreq->dev.parent->of_node == node) {
> +			mutex_unlock(&devfreq_list_lock);
> +			return devfreq;
> +		}
> +	}
> +	mutex_unlock(&devfreq_list_lock);
> +
> +	return ERR_PTR(-ENODEV);
> +}
> +
>   /*
>    * devfreq_get_devfreq_by_phandle - Get the devfreq device from devicetree
>    * @dev - instance to the given device
> @@ -988,26 +1014,24 @@ struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
>   	if (!node)
>   		return ERR_PTR(-ENODEV);
>   
> -	mutex_lock(&devfreq_list_lock);
> -	list_for_each_entry(devfreq, &devfreq_list, node) {
> -		if (devfreq->dev.parent
> -			&& devfreq->dev.parent->of_node == node) {
> -			mutex_unlock(&devfreq_list_lock);
> -			of_node_put(node);
> -			return devfreq;
> -		}
> -	}
> -	mutex_unlock(&devfreq_list_lock);
> +	devfreq = devfreq_get_devfreq_by_node(node);
>   	of_node_put(node);
>   
> -	return ERR_PTR(-EPROBE_DEFER);
> +	return devfreq;
>   }
> +
>   #else
> +struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
> +{
> +	return ERR_PTR(-ENODEV);
> +}
> +
>   struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
>   {
>   	return ERR_PTR(-ENODEV);
>   }
>   #endif /* CONFIG_OF */
> +EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_node);
>   EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_phandle);
>   
>   /**
> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
> index c6f82d4bec9f..1dccc47acbce 100644
> --- a/include/linux/devfreq.h
> +++ b/include/linux/devfreq.h
> @@ -253,6 +253,7 @@ extern void devm_devfreq_unregister_notifier(struct device *dev,
>   				struct devfreq *devfreq,
>   				struct notifier_block *nb,
>   				unsigned int list);
> +extern struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node);

It can go without 'extern' in the header.

>   extern struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev,
>   						int index);
>   
> @@ -407,6 +408,11 @@ static inline void devm_devfreq_unregister_notifier(struct device *dev,
>   {
>   }
>   
> +static inline struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
> +{
> +	return ERR_PTR(-ENODEV);
> +}
> +
>   static inline struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev,
>   							int index)
>   {
> 

Apart from this minor thing, looks good to me.
When you fix it, feel free to add

Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>

Regards,
Lukasz
Lukasz Luba Jan. 9, 2020, 10:37 a.m. UTC | #6
Hi Chanwoo,

On 12/20/19 12:24 AM, Chanwoo Choi wrote:
> Previously, devfreq core support 'devfreq' property in order to get
> the devfreq device by phandle. But, 'devfreq' property name is not proper
> on devicetree binding because this name doesn't mean the any h/w attribute.
> 
> The devfreq core hand over the right to decide the property name
> for getting the devfreq device on devicetree. Each devfreq driver
> will decide the property name on devicetree binding and then get
> the devfreq device by using devfreq_get_devfreq_by_node().
> 
> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
> ---
>   drivers/devfreq/devfreq.c    | 35 -----------------------------------
>   drivers/devfreq/exynos-bus.c | 12 +++++++++++-
>   include/linux/devfreq.h      |  8 --------
>   3 files changed, 11 insertions(+), 44 deletions(-)
> 
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index cb8ca81c8973..c3d3c7c802a0 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -991,48 +991,13 @@ struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
>   
>   	return ERR_PTR(-ENODEV);
>   }
> -
> -/*
> - * devfreq_get_devfreq_by_phandle - Get the devfreq device from devicetree
> - * @dev - instance to the given device
> - * @index - index into list of devfreq
> - *
> - * return the instance of devfreq device
> - */
> -struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
> -{
> -	struct device_node *node;
> -	struct devfreq *devfreq;
> -
> -	if (!dev)
> -		return ERR_PTR(-EINVAL);
> -
> -	if (!dev->of_node)
> -		return ERR_PTR(-EINVAL);
> -
> -	node = of_parse_phandle(dev->of_node, "devfreq", index);
> -	if (!node)
> -		return ERR_PTR(-ENODEV);
> -
> -	devfreq = devfreq_get_devfreq_by_node(node);
> -	of_node_put(node);
> -
> -	return devfreq;
> -}
> -
>   #else
>   struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
>   {
>   	return ERR_PTR(-ENODEV);
>   }
> -
> -struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
> -{
> -	return ERR_PTR(-ENODEV);
> -}
>   #endif /* CONFIG_OF */
>   EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_node);
> -EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_phandle);
>   
>   /**
>    * devm_devfreq_remove_device() - Resource-managed devfreq_remove_device()
> diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
> index 7f5917d59072..1bc4e3c81115 100644
> --- a/drivers/devfreq/exynos-bus.c
> +++ b/drivers/devfreq/exynos-bus.c
> @@ -86,6 +86,16 @@ static int exynos_bus_get_event(struct exynos_bus *bus,
>   	return ret;
>   }
>   
> +static struct devfreq *exynos_bus_get_parent_devfreq(struct device_node *np)
> +{
> +	struct device_node *node = of_parse_phandle(np, "devfreq", 0);
> +
> +	if (!node)
> +		return ERR_PTR(-ENODEV);
> +
> +	return devfreq_get_devfreq_by_node(node);
> +}
> +
>   /*
>    * devfreq function for both simple-ondemand and passive governor
>    */
> @@ -353,7 +363,7 @@ static int exynos_bus_profile_init_passive(struct exynos_bus *bus,
>   	profile->exit = exynos_bus_passive_exit;
>   
>   	/* Get the instance of parent devfreq device */
> -	parent_devfreq = devfreq_get_devfreq_by_phandle(dev, 0);
> +	parent_devfreq = exynos_bus_get_parent_devfreq(dev->of_node);
>   	if (IS_ERR(parent_devfreq))
>   		return -EPROBE_DEFER;
>   

These changes won't apply, probably I need some base for it.

Regards,
Lukasz
Chanwoo Choi Jan. 9, 2020, 10:54 a.m. UTC | #7
On 1/9/20 7:37 PM, Lukasz Luba wrote:
> Hi Chanwoo,
> 
> On 12/20/19 12:24 AM, Chanwoo Choi wrote:
>> Previously, devfreq core support 'devfreq' property in order to get
>> the devfreq device by phandle. But, 'devfreq' property name is not proper
>> on devicetree binding because this name doesn't mean the any h/w attribute.
>>
>> The devfreq core hand over the right to decide the property name
>> for getting the devfreq device on devicetree. Each devfreq driver
>> will decide the property name on devicetree binding and then get
>> the devfreq device by using devfreq_get_devfreq_by_node().
>>
>> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
>> ---
>>   drivers/devfreq/devfreq.c    | 35 -----------------------------------
>>   drivers/devfreq/exynos-bus.c | 12 +++++++++++-
>>   include/linux/devfreq.h      |  8 --------
>>   3 files changed, 11 insertions(+), 44 deletions(-)
>>
>> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
>> index cb8ca81c8973..c3d3c7c802a0 100644
>> --- a/drivers/devfreq/devfreq.c
>> +++ b/drivers/devfreq/devfreq.c
>> @@ -991,48 +991,13 @@ struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
>>         return ERR_PTR(-ENODEV);
>>   }
>> -
>> -/*
>> - * devfreq_get_devfreq_by_phandle - Get the devfreq device from devicetree
>> - * @dev - instance to the given device
>> - * @index - index into list of devfreq
>> - *
>> - * return the instance of devfreq device
>> - */
>> -struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
>> -{
>> -    struct device_node *node;
>> -    struct devfreq *devfreq;
>> -
>> -    if (!dev)
>> -        return ERR_PTR(-EINVAL);
>> -
>> -    if (!dev->of_node)
>> -        return ERR_PTR(-EINVAL);
>> -
>> -    node = of_parse_phandle(dev->of_node, "devfreq", index);
>> -    if (!node)
>> -        return ERR_PTR(-ENODEV);
>> -
>> -    devfreq = devfreq_get_devfreq_by_node(node);
>> -    of_node_put(node);
>> -
>> -    return devfreq;
>> -}
>> -
>>   #else
>>   struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
>>   {
>>       return ERR_PTR(-ENODEV);
>>   }
>> -
>> -struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
>> -{
>> -    return ERR_PTR(-ENODEV);
>> -}
>>   #endif /* CONFIG_OF */
>>   EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_node);
>> -EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_phandle);
>>     /**
>>    * devm_devfreq_remove_device() - Resource-managed devfreq_remove_device()
>> diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
>> index 7f5917d59072..1bc4e3c81115 100644
>> --- a/drivers/devfreq/exynos-bus.c
>> +++ b/drivers/devfreq/exynos-bus.c
>> @@ -86,6 +86,16 @@ static int exynos_bus_get_event(struct exynos_bus *bus,
>>       return ret;
>>   }
>>   +static struct devfreq *exynos_bus_get_parent_devfreq(struct device_node *np)
>> +{
>> +    struct device_node *node = of_parse_phandle(np, "devfreq", 0);
>> +
>> +    if (!node)
>> +        return ERR_PTR(-ENODEV);
>> +
>> +    return devfreq_get_devfreq_by_node(node);
>> +}
>> +
>>   /*
>>    * devfreq function for both simple-ondemand and passive governor
>>    */
>> @@ -353,7 +363,7 @@ static int exynos_bus_profile_init_passive(struct exynos_bus *bus,
>>       profile->exit = exynos_bus_passive_exit;
>>         /* Get the instance of parent devfreq device */
>> -    parent_devfreq = devfreq_get_devfreq_by_phandle(dev, 0);
>> +    parent_devfreq = exynos_bus_get_parent_devfreq(dev->of_node);
>>       if (IS_ERR(parent_devfreq))
>>           return -EPROBE_DEFER;
>>   
> 
> These changes won't apply, probably I need some base for it.

I developed it on devfreq-next branch[1]
[1] https://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/linux.git/log/?h=devfreq-next

And I try to apply these patchset to linux-next[2] with tags/next-20200109.
But, patch10/11 of deviceetree has some merge conflict
because patch[3] related to exynos-bus was merged.
[2] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/log/
[3] https://patchwork.kernel.org/cover/11303235/
    - [v2,0/2] Exynos5422: fix bus related OPPs for Odroid XU3/XU4/HC1

On next version, I'll rebase it on latest patches.

> 
> Regards,
> Lukasz
> 
> 
>
Lukasz Luba Jan. 9, 2020, 10:57 a.m. UTC | #8
On 1/9/20 10:54 AM, Chanwoo Choi wrote:
> On 1/9/20 7:37 PM, Lukasz Luba wrote:
>> Hi Chanwoo,
>>
>> On 12/20/19 12:24 AM, Chanwoo Choi wrote:
>>> Previously, devfreq core support 'devfreq' property in order to get
>>> the devfreq device by phandle. But, 'devfreq' property name is not proper
>>> on devicetree binding because this name doesn't mean the any h/w attribute.
>>>
>>> The devfreq core hand over the right to decide the property name
>>> for getting the devfreq device on devicetree. Each devfreq driver
>>> will decide the property name on devicetree binding and then get
>>> the devfreq device by using devfreq_get_devfreq_by_node().
>>>
>>> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
>>> ---
>>>    drivers/devfreq/devfreq.c    | 35 -----------------------------------
>>>    drivers/devfreq/exynos-bus.c | 12 +++++++++++-
>>>    include/linux/devfreq.h      |  8 --------
>>>    3 files changed, 11 insertions(+), 44 deletions(-)
>>>
>>> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
>>> index cb8ca81c8973..c3d3c7c802a0 100644
>>> --- a/drivers/devfreq/devfreq.c
>>> +++ b/drivers/devfreq/devfreq.c
>>> @@ -991,48 +991,13 @@ struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
>>>          return ERR_PTR(-ENODEV);
>>>    }
>>> -
>>> -/*
>>> - * devfreq_get_devfreq_by_phandle - Get the devfreq device from devicetree
>>> - * @dev - instance to the given device
>>> - * @index - index into list of devfreq
>>> - *
>>> - * return the instance of devfreq device
>>> - */
>>> -struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
>>> -{
>>> -    struct device_node *node;
>>> -    struct devfreq *devfreq;
>>> -
>>> -    if (!dev)
>>> -        return ERR_PTR(-EINVAL);
>>> -
>>> -    if (!dev->of_node)
>>> -        return ERR_PTR(-EINVAL);
>>> -
>>> -    node = of_parse_phandle(dev->of_node, "devfreq", index);
>>> -    if (!node)
>>> -        return ERR_PTR(-ENODEV);
>>> -
>>> -    devfreq = devfreq_get_devfreq_by_node(node);
>>> -    of_node_put(node);
>>> -
>>> -    return devfreq;
>>> -}
>>> -
>>>    #else
>>>    struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
>>>    {
>>>        return ERR_PTR(-ENODEV);
>>>    }
>>> -
>>> -struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
>>> -{
>>> -    return ERR_PTR(-ENODEV);
>>> -}
>>>    #endif /* CONFIG_OF */
>>>    EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_node);
>>> -EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_phandle);
>>>      /**
>>>     * devm_devfreq_remove_device() - Resource-managed devfreq_remove_device()
>>> diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
>>> index 7f5917d59072..1bc4e3c81115 100644
>>> --- a/drivers/devfreq/exynos-bus.c
>>> +++ b/drivers/devfreq/exynos-bus.c
>>> @@ -86,6 +86,16 @@ static int exynos_bus_get_event(struct exynos_bus *bus,
>>>        return ret;
>>>    }
>>>    +static struct devfreq *exynos_bus_get_parent_devfreq(struct device_node *np)
>>> +{
>>> +    struct device_node *node = of_parse_phandle(np, "devfreq", 0);
>>> +
>>> +    if (!node)
>>> +        return ERR_PTR(-ENODEV);
>>> +
>>> +    return devfreq_get_devfreq_by_node(node);
>>> +}
>>> +
>>>    /*
>>>     * devfreq function for both simple-ondemand and passive governor
>>>     */
>>> @@ -353,7 +363,7 @@ static int exynos_bus_profile_init_passive(struct exynos_bus *bus,
>>>        profile->exit = exynos_bus_passive_exit;
>>>          /* Get the instance of parent devfreq device */
>>> -    parent_devfreq = devfreq_get_devfreq_by_phandle(dev, 0);
>>> +    parent_devfreq = exynos_bus_get_parent_devfreq(dev->of_node);
>>>        if (IS_ERR(parent_devfreq))
>>>            return -EPROBE_DEFER;
>>>    
>>
>> These changes won't apply, probably I need some base for it.
> 
> I developed it on devfreq-next branch[1]
> [1] https://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/linux.git/log/?h=devfreq-next
> 
> And I try to apply these patchset to linux-next[2] with tags/next-20200109.
> But, patch10/11 of deviceetree has some merge conflict
> because patch[3] related to exynos-bus was merged.
> [2] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/log/
> [3] https://patchwork.kernel.org/cover/11303235/
>      - [v2,0/2] Exynos5422: fix bus related OPPs for Odroid XU3/XU4/HC1
> 
> On next version, I'll rebase it on latest patches.

Thank you for the information. I will update the base and continue the
review.

Lukasz