Re: [RFC PATCH v2 01/11] devfreq: exynos-bus: Extract exynos_bus_profile_init()

["Artur Świgoń" <a.swigon@samsung.com>]

On Wed, 2019-09-25 at 15:37 +0900, Chanwoo Choi wrote:
> Hi,
> 
> On 19. 9. 25. 오후 2:44, Artur Świgoń wrote:
> > Hi,
> > 
> > On Fri, 2019-09-20 at 11:15 +0900, Chanwoo Choi wrote:
> > > Hi,
> > > 
> > > As I already replied on v1, patch1/2/3 clean-up code
> > > for readability without any behavior changes. 
> > > 
> > > I think that you better to merge patch1/2/3 to one patch.
> > 
> > Yes, when writing the cover letter I think I forgot to explain why I decided not
> > to merge these patches. Basically, none of the diff algorithms available in git
> > (I've got v2.17.1) is able to produce a readable patch with these changes
> > combined together into a single patch (functions are intermixed together in the
> > output, git thinks that 'exynos_bus_probe' is a new function).
> 
> After merged three patches, as you commented, looks like that 'exynos_bus_probe'
> is new function. Your patch style(three patches) is better than one merged patch.
> Keep your original patches. Thanks.

I know that having three separate patches is suboptimal, but they are more readable
this way. I am glad you agree. I will keep them separate. Thank you for your
comments.

> > 
> > Please take a look at the diff at the bottom of this message to see how patches
> > 01..03 look when combined. If such patch looks acceptable to you, I can merge.
> > 
> > > On 19. 9. 19. 오후 11:22, Artur Świgoń wrote:
> > > > From: Artur Świgoń <a.swigon@partner.samsung.com>
> > > > 
> > > > This patch adds a new static function, exynos_bus_profile_init(), extracted
> > > > from exynos_bus_probe().
> > > > 
> > > > Signed-off-by: Artur Świgoń <a.swigon@partner.samsung.com>
> > > > ---
> > > >  drivers/devfreq/exynos-bus.c | 92 +++++++++++++++++++++---------------
> > > >  1 file changed, 53 insertions(+), 39 deletions(-)
> > > > 
> > > > diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
> > > > index 29f422469960..78f38b7fb596 100644
> > > > --- a/drivers/devfreq/exynos-bus.c
> > > > +++ b/drivers/devfreq/exynos-bus.c
> > > > @@ -287,12 +287,62 @@ static int exynos_bus_parse_of(struct device_node *np,
> > > >  	return ret;
> > > >  }
> > > >  
> > > > +static int exynos_bus_profile_init(struct exynos_bus *bus,
> > > > +				   struct devfreq_dev_profile *profile)
> > > > +{
> > > > +	struct device *dev = bus->dev;
> > > > +	struct devfreq_simple_ondemand_data *ondemand_data;
> > > > +	int ret;
> > > > +
> > > > +	/* Initialize the struct profile and governor data for parent device */
> > > > +	profile->polling_ms = 50;
> > > > +	profile->target = exynos_bus_target;
> > > > +	profile->get_dev_status = exynos_bus_get_dev_status;
> > > > +	profile->exit = exynos_bus_exit;
> > > > +
> > > > +	ondemand_data = devm_kzalloc(dev, sizeof(*ondemand_data), GFP_KERNEL);
> > > > +	if (!ondemand_data) {
> > > > +		ret = -ENOMEM;
> > > > +		goto err;
> > > > +	}
> > > > +	ondemand_data->upthreshold = 40;
> > > > +	ondemand_data->downdifferential = 5;
> > > > +
> > > > +	/* Add devfreq device to monitor and handle the exynos bus */
> > > > +	bus->devfreq = devm_devfreq_add_device(dev, profile,
> > > > +						DEVFREQ_GOV_SIMPLE_ONDEMAND,
> > > > +						ondemand_data);
> > > > +	if (IS_ERR(bus->devfreq)) {
> > > > +		dev_err(dev, "failed to add devfreq device\n");
> > > > +		ret = PTR_ERR(bus->devfreq);
> > > > +		goto err;
> > > > +	}
> > > > +
> > > > +	/*
> > > > +	 * Enable devfreq-event to get raw data which is used to determine
> > > > +	 * current bus load.
> > > > +	 */
> > > > +	ret = exynos_bus_enable_edev(bus);
> > > > +	if (ret < 0) {
> > > > +		dev_err(dev, "failed to enable devfreq-event devices\n");
> > > > +		goto err;
> > > > +	}
> > > > +
> > > > +	ret = exynos_bus_set_event(bus);
> > > > +	if (ret < 0) {
> > > > +		dev_err(dev, "failed to set event to devfreq-event devices\n");
> > > > +		goto err;
> > > > +	}
> > > > +
> > > > +err:
> > > > +	return ret;
> > > > +}
> > > > +
> > > >  static int exynos_bus_probe(struct platform_device *pdev)
> > > >  {
> > > >  	struct device *dev = &pdev->dev;
> > > >  	struct device_node *np = dev->of_node, *node;
> > > >  	struct devfreq_dev_profile *profile;
> > > > -	struct devfreq_simple_ondemand_data *ondemand_data;
> > > >  	struct devfreq_passive_data *passive_data;
> > > >  	struct devfreq *parent_devfreq;
> > > >  	struct exynos_bus *bus;
> > > > @@ -334,45 +384,9 @@ static int exynos_bus_probe(struct platform_device *pdev)
> > > >  	if (passive)
> > > >  		goto passive;
> > > >  
> > > > -	/* Initialize the struct profile and governor data for parent device */
> > > > -	profile->polling_ms = 50;
> > > > -	profile->target = exynos_bus_target;
> > > > -	profile->get_dev_status = exynos_bus_get_dev_status;
> > > > -	profile->exit = exynos_bus_exit;
> > > > -
> > > > -	ondemand_data = devm_kzalloc(dev, sizeof(*ondemand_data), GFP_KERNEL);
> > > > -	if (!ondemand_data) {
> > > > -		ret = -ENOMEM;
> > > > +	ret = exynos_bus_profile_init(bus, profile);
> > > > +	if (ret < 0)
> > > >  		goto err;
> > > > -	}
> > > > -	ondemand_data->upthreshold = 40;
> > > > -	ondemand_data->downdifferential = 5;
> > > > -
> > > > -	/* Add devfreq device to monitor and handle the exynos bus */
> > > > -	bus->devfreq = devm_devfreq_add_device(dev, profile,
> > > > -						DEVFREQ_GOV_SIMPLE_ONDEMAND,
> > > > -						ondemand_data);
> > > > -	if (IS_ERR(bus->devfreq)) {
> > > > -		dev_err(dev, "failed to add devfreq device\n");
> > > > -		ret = PTR_ERR(bus->devfreq);
> > > > -		goto err;
> > > > -	}
> > > > -
> > > > -	/*
> > > > -	 * Enable devfreq-event to get raw data which is used to determine
> > > > -	 * current bus load.
> > > > -	 */
> > > > -	ret = exynos_bus_enable_edev(bus);
> > > > -	if (ret < 0) {
> > > > -		dev_err(dev, "failed to enable devfreq-event devices\n");
> > > > -		goto err;
> > > > -	}
> > > > -
> > > > -	ret = exynos_bus_set_event(bus);
> > > > -	if (ret < 0) {
> > > > -		dev_err(dev, "failed to set event to devfreq-event devices\n");
> > > > -		goto err;
> > > > -	}
> > > >  
> > > >  	goto out;
> > > >  passive:
> > 
> > commit cacf8e4ea0e111908d11779977c81e29d6418801
> > Author: Artur Świgoń <a.swigon@partner.samsung.com>
> > Date:   Tue Aug 27 13:17:28 2019 +0200
> > 
> >     tmp: merge patches 01-03
> >     
> >     Signed-off-by: Artur Świgoń <a.swigon@partner.samsung.com>
> > 
> > diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
> > index 29f422469960..60ad4319fd80 100644
> > --- a/drivers/devfreq/exynos-bus.c
> > +++ b/drivers/devfreq/exynos-bus.c
> > @@ -287,52 +287,12 @@ static int exynos_bus_parse_of(struct device_node *np,
> >  	return ret;
> >  }
> >  
> > -static int exynos_bus_probe(struct platform_device *pdev)
> > +static int exynos_bus_profile_init(struct exynos_bus *bus,
> > +				   struct devfreq_dev_profile *profile)
> >  {
> > -	struct device *dev = &pdev->dev;
> > -	struct device_node *np = dev->of_node, *node;
> > -	struct devfreq_dev_profile *profile;
> > +	struct device *dev = bus->dev;
> >  	struct devfreq_simple_ondemand_data *ondemand_data;
> > -	struct devfreq_passive_data *passive_data;
> > -	struct devfreq *parent_devfreq;
> > -	struct exynos_bus *bus;
> > -	int ret, max_state;
> > -	unsigned long min_freq, max_freq;
> > -	bool passive = false;
> > -
> > -	if (!np) {
> > -		dev_err(dev, "failed to find devicetree node\n");
> > -		return -EINVAL;
> > -	}
> > -
> > -	bus = devm_kzalloc(&pdev->dev, sizeof(*bus), GFP_KERNEL);
> > -	if (!bus)
> > -		return -ENOMEM;
> > -	mutex_init(&bus->lock);
> > -	bus->dev = &pdev->dev;
> > -	platform_set_drvdata(pdev, bus);
> > -
> > -	profile = devm_kzalloc(dev, sizeof(*profile), GFP_KERNEL);
> > -	if (!profile)
> > -		return -ENOMEM;
> > -
> > -	node = of_parse_phandle(dev->of_node, "devfreq", 0);
> > -	if (node) {
> > -		of_node_put(node);
> > -		passive = true;
> > -	} else {
> > -		ret = exynos_bus_parent_parse_of(np, bus);
> > -		if (ret < 0)
> > -			return ret;
> > -	}
> > -
> > -	/* Parse the device-tree to get the resource information */
> > -	ret = exynos_bus_parse_of(np, bus);
> > -	if (ret < 0)
> > -		goto err_reg;
> > -
> > -	if (passive)
> > -		goto passive;
> > +	int ret;
> >  
> >  	/* Initialize the struct profile and governor data for parent device */
> >  	profile->polling_ms = 50;
> > @@ -374,8 +334,18 @@ static int exynos_bus_probe(struct platform_device *pdev)
> >  		goto err;
> >  	}
> >  
> > -	goto out;
> > -passive:
> > +err:
> > +	return ret;
> > +}
> > +
> > +static int exynos_bus_profile_init_passive(struct exynos_bus *bus,
> > +					   struct devfreq_dev_profile *profile)
> > +{
> > +	struct device *dev = bus->dev;
> > +	struct devfreq_passive_data *passive_data;
> > +	struct devfreq *parent_devfreq;
> > +	int ret = 0;
> > +
> >  	/* Initialize the struct profile and governor data for passive device */
> >  	profile->target = exynos_bus_target;
> >  	profile->exit = exynos_bus_passive_exit;
> > @@ -404,7 +374,59 @@ static int exynos_bus_probe(struct platform_device *pdev)
> >  		goto err;
> >  	}
> >  
> > -out:
> > +err:
> > +	return ret;
> > +}
> > +
> > +static int exynos_bus_probe(struct platform_device *pdev)
> > +{
> > +	struct device *dev = &pdev->dev;
> > +	struct device_node *np = dev->of_node, *node;
> > +	struct devfreq_dev_profile *profile;
> > +	struct exynos_bus *bus;
> > +	int ret, max_state;
> > +	unsigned long min_freq, max_freq;
> > +	bool passive = false;
> > +
> > +	if (!np) {
> > +		dev_err(dev, "failed to find devicetree node\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	bus = devm_kzalloc(&pdev->dev, sizeof(*bus), GFP_KERNEL);
> > +	if (!bus)
> > +		return -ENOMEM;
> > +	mutex_init(&bus->lock);
> > +	bus->dev = &pdev->dev;
> > +	platform_set_drvdata(pdev, bus);
> > +
> > +	profile = devm_kzalloc(dev, sizeof(*profile), GFP_KERNEL);
> > +	if (!profile)
> > +		return -ENOMEM;
> > +
> > +	node = of_parse_phandle(dev->of_node, "devfreq", 0);
> > +	if (node) {
> > +		of_node_put(node);
> > +		passive = true;
> > +	} else {
> > +		ret = exynos_bus_parent_parse_of(np, bus);
> > +		if (ret < 0)
> > +			return ret;
> > +	}
> > +
> > +	/* Parse the device-tree to get the resource information */
> > +	ret = exynos_bus_parse_of(np, bus);
> > +	if (ret < 0)
> > +		goto err_reg;
> > +
> > +	if (passive)
> > +		ret = exynos_bus_profile_init_passive(bus, profile);
> > +	else
> > +		ret = exynos_bus_profile_init(bus, profile);
> > +
> > +	if (ret < 0)
> > +		goto err;
> > +
> >  	max_state = bus->devfreq->profile->max_state;
> >  	min_freq = (bus->devfreq->profile->freq_table[0] / 1000);
> >  	max_freq = (bus->devfreq->profile->freq_table[max_state - 1] / 1000);
> > 
> > 
> > 
> > 
> 
> 
-- 
Artur Świgoń
Samsung R&D Institute Poland
Samsung Electronics