[PATCH 0/3] PM / Domains: Improve support for multi PM domains

[PATCH 0/3] PM / Domains: Improve support for multi PM domains

[Ulf Hansson]

It's been a while since the introduction for the support for multi PM domains
per device in genpd. In this small series, a couple of different improvement
are being made to this code in genpd.

Ulf Hansson (3):
  PM / Domains: Don't kfree() the virtual device in the error path
  PM / Domains: Allow OF lookup for multi PM domain case from
    ->attach_dev()
  PM / Domains: Enable genpd_dev_pm_attach_by_id|name() for single PM
    domain

 drivers/base/power/domain.c | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

-- 
2.17.1

[PATCH 1/3] PM / Domains: Don't kfree() the virtual device in the error path

[Ulf Hansson]

It's not correct to call kfree(dev) when device_register(dev) has failed.
Fix this by calling put_device(dev) instead.

Fixes: 3c095f32a92b ("PM / Domains: Add support for multi PM domains per device to genpd")
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
---
 drivers/base/power/domain.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index ecac03dcc9b2..7fec69aebf46 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -2528,7 +2528,7 @@ struct device *genpd_dev_pm_attach_by_id(struct device *dev,
 
 	ret = device_register(virt_dev);
 	if (ret) {
-		kfree(virt_dev);
+		put_device(virt_dev);
 		return ERR_PTR(ret);
 	}
 
-- 
2.17.1

[PATCH 2/3] PM / Domains: Allow OF lookup for multi PM domain case from ->attach_dev()

[Ulf Hansson]

A genpd provider that uses the ->attach_dev() callback to lookup resources
for a device, fails to do so when the device has multiple PM domains. This
is because when genpd invokes the ->attach_dev() callback, it passes the
allocated virtual device as the in-parameter.

To address this problem, let's simply assign the dev->of_node for the
virtual device, based upon the original device's OF node.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
---
 drivers/base/power/domain.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 7fec69aebf46..801f31c87d16 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -2345,6 +2345,7 @@ EXPORT_SYMBOL_GPL(of_genpd_remove_last);
 
 static void genpd_release_dev(struct device *dev)
 {
+	of_node_put(dev->of_node);
 	kfree(dev);
 }
 
@@ -2406,14 +2407,14 @@ static void genpd_dev_pm_sync(struct device *dev)
 	genpd_queue_power_off_work(pd);
 }
 
-static int __genpd_dev_pm_attach(struct device *dev, struct device_node *np,
-				 unsigned int index, bool power_on)
+static int __genpd_dev_pm_attach(struct device *dev, unsigned int index,
+				 bool power_on)
 {
 	struct of_phandle_args pd_args;
 	struct generic_pm_domain *pd;
 	int ret;
 
-	ret = of_parse_phandle_with_args(np, "power-domains",
+	ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
 				"#power-domain-cells", index, &pd_args);
 	if (ret < 0)
 		return ret;
@@ -2481,7 +2482,7 @@ int genpd_dev_pm_attach(struct device *dev)
 				       "#power-domain-cells") != 1)
 		return 0;
 
-	return __genpd_dev_pm_attach(dev, dev->of_node, 0, true);
+	return __genpd_dev_pm_attach(dev, 0, true);
 }
 EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
 
@@ -2525,6 +2526,7 @@ struct device *genpd_dev_pm_attach_by_id(struct device *dev,
 	dev_set_name(virt_dev, "genpd:%u:%s", index, dev_name(dev));
 	virt_dev->bus = &genpd_bus_type;
 	virt_dev->release = genpd_release_dev;
+	virt_dev->of_node = of_node_get(dev->of_node);
 
 	ret = device_register(virt_dev);
 	if (ret) {
@@ -2533,7 +2535,7 @@ struct device *genpd_dev_pm_attach_by_id(struct device *dev,
 	}
 
 	/* Try to attach the device to the PM domain at the specified index. */
-	ret = __genpd_dev_pm_attach(virt_dev, dev->of_node, index, false);
+	ret = __genpd_dev_pm_attach(virt_dev, index, false);
 	if (ret < 1) {
 		device_unregister(virt_dev);
 		return ret ? ERR_PTR(ret) : NULL;
-- 
2.17.1

[PATCH 3/3] PM / Domains: Enable genpd_dev_pm_attach_by_id|name() for single PM domain

[Ulf Hansson]

If a call to dev_pm_domain_attach() succeeds to attach a device to its
single PM domain, the important point is to prevent following calls to
dev_pm_domain_attach_by_name|id() to fail. This is managed by checking the
dev->pm_domain pointer and then return -EEXIST, rather than continue
calling genpd_dev_pm_attach_by_id|name().

For this reason, let's enable genpd_dev_pm_attach_by_id|name() to be used
for also single PM domains. This simplifies for future users to solely make
use of dev_pm_domain_attach_by_id|name() rather than having to combine it
with dev_pm_domain_attach().

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
---
 drivers/base/power/domain.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 801f31c87d16..1b026704a8fc 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -2512,10 +2512,10 @@ struct device *genpd_dev_pm_attach_by_id(struct device *dev,
 	if (!dev->of_node)
 		return NULL;
 
-	/* Deal only with devices using multiple PM domains. */
+	/* Verify that the index is within a valid range. */
 	num_domains = of_count_phandle_with_args(dev->of_node, "power-domains",
 						 "#power-domain-cells");
-	if (num_domains < 2 || index >= num_domains)
+	if (index >= num_domains)
 		return NULL;
 
 	/* Allocate and register device on the genpd bus. */
-- 
2.17.1

Re: [PATCH 1/3] PM / Domains: Don't kfree() the virtual device in the error path

[Viresh Kumar]

On 18-04-19, 12:27, Ulf Hansson wrote:
> It's not correct to call kfree(dev) when device_register(dev) has failed.
> Fix this by calling put_device(dev) instead.
> 
> Fixes: 3c095f32a92b ("PM / Domains: Add support for multi PM domains per device to genpd")
> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
> ---
>  drivers/base/power/domain.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> index ecac03dcc9b2..7fec69aebf46 100644
> --- a/drivers/base/power/domain.c
> +++ b/drivers/base/power/domain.c
> @@ -2528,7 +2528,7 @@ struct device *genpd_dev_pm_attach_by_id(struct device *dev,
>  
>  	ret = device_register(virt_dev);
>  	if (ret) {
> -		kfree(virt_dev);
> +		put_device(virt_dev);
>  		return ERR_PTR(ret);
>  	}

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

-- 
viresh

Re: [PATCH 2/3] PM / Domains: Allow OF lookup for multi PM domain case from ->attach_dev()

[Viresh Kumar]

On 18-04-19, 12:27, Ulf Hansson wrote:
> A genpd provider that uses the ->attach_dev() callback to lookup resources
> for a device, fails to do so when the device has multiple PM domains. This
> is because when genpd invokes the ->attach_dev() callback, it passes the
> allocated virtual device as the in-parameter.
> 
> To address this problem, let's simply assign the dev->of_node for the
> virtual device, based upon the original device's OF node.
> 
> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
> ---
>  drivers/base/power/domain.c | 12 +++++++-----
>  1 file changed, 7 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> index 7fec69aebf46..801f31c87d16 100644
> --- a/drivers/base/power/domain.c
> +++ b/drivers/base/power/domain.c
> @@ -2345,6 +2345,7 @@ EXPORT_SYMBOL_GPL(of_genpd_remove_last);
>  
>  static void genpd_release_dev(struct device *dev)
>  {
> +	of_node_put(dev->of_node);
>  	kfree(dev);
>  }
>  
> @@ -2406,14 +2407,14 @@ static void genpd_dev_pm_sync(struct device *dev)
>  	genpd_queue_power_off_work(pd);
>  }
>  
> -static int __genpd_dev_pm_attach(struct device *dev, struct device_node *np,
> -				 unsigned int index, bool power_on)
> +static int __genpd_dev_pm_attach(struct device *dev, unsigned int index,
> +				 bool power_on)
>  {
>  	struct of_phandle_args pd_args;
>  	struct generic_pm_domain *pd;
>  	int ret;
>  
> -	ret = of_parse_phandle_with_args(np, "power-domains",
> +	ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
>  				"#power-domain-cells", index, &pd_args);
>  	if (ret < 0)
>  		return ret;
> @@ -2481,7 +2482,7 @@ int genpd_dev_pm_attach(struct device *dev)
>  				       "#power-domain-cells") != 1)
>  		return 0;
>  
> -	return __genpd_dev_pm_attach(dev, dev->of_node, 0, true);
> +	return __genpd_dev_pm_attach(dev, 0, true);
>  }
>  EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
>  
> @@ -2525,6 +2526,7 @@ struct device *genpd_dev_pm_attach_by_id(struct device *dev,
>  	dev_set_name(virt_dev, "genpd:%u:%s", index, dev_name(dev));
>  	virt_dev->bus = &genpd_bus_type;
>  	virt_dev->release = genpd_release_dev;
> +	virt_dev->of_node = of_node_get(dev->of_node);
>  
>  	ret = device_register(virt_dev);
>  	if (ret) {
> @@ -2533,7 +2535,7 @@ struct device *genpd_dev_pm_attach_by_id(struct device *dev,
>  	}
>  
>  	/* Try to attach the device to the PM domain at the specified index. */
> -	ret = __genpd_dev_pm_attach(virt_dev, dev->of_node, index, false);
> +	ret = __genpd_dev_pm_attach(virt_dev, index, false);
>  	if (ret < 1) {
>  		device_unregister(virt_dev);
>  		return ret ? ERR_PTR(ret) : NULL;

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

-- 
viresh

Re: [PATCH 3/3] PM / Domains: Enable genpd_dev_pm_attach_by_id|name() for single PM domain

[Viresh Kumar]

On 18-04-19, 12:27, Ulf Hansson wrote:
> If a call to dev_pm_domain_attach() succeeds to attach a device to its
> single PM domain, the important point is to prevent following calls to
> dev_pm_domain_attach_by_name|id() to fail. This is managed by checking the
> dev->pm_domain pointer and then return -EEXIST, rather than continue
> calling genpd_dev_pm_attach_by_id|name().
> 
> For this reason, let's enable genpd_dev_pm_attach_by_id|name() to be used
> for also single PM domains. This simplifies for future users to solely make
> use of dev_pm_domain_attach_by_id|name() rather than having to combine it
> with dev_pm_domain_attach().
> 
> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
> ---
>  drivers/base/power/domain.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> index 801f31c87d16..1b026704a8fc 100644
> --- a/drivers/base/power/domain.c
> +++ b/drivers/base/power/domain.c
> @@ -2512,10 +2512,10 @@ struct device *genpd_dev_pm_attach_by_id(struct device *dev,
>  	if (!dev->of_node)
>  		return NULL;
>  
> -	/* Deal only with devices using multiple PM domains. */
> +	/* Verify that the index is within a valid range. */
>  	num_domains = of_count_phandle_with_args(dev->of_node, "power-domains",
>  						 "#power-domain-cells");
> -	if (num_domains < 2 || index >= num_domains)
> +	if (index >= num_domains)
>  		return NULL;
>  
>  	/* Allocate and register device on the genpd bus. */

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

-- 
viresh

Re: [PATCH 1/3] PM / Domains: Don't kfree() the virtual device in the error path

[Niklas Cassel]

On Thu, Apr 18, 2019 at 12:27:55PM +0200, Ulf Hansson wrote:
> It's not correct to call kfree(dev) when device_register(dev) has failed.
> Fix this by calling put_device(dev) instead.
> 
> Fixes: 3c095f32a92b ("PM / Domains: Add support for multi PM domains per device to genpd")
> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
> ---
>  drivers/base/power/domain.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> index ecac03dcc9b2..7fec69aebf46 100644
> --- a/drivers/base/power/domain.c
> +++ b/drivers/base/power/domain.c
> @@ -2528,7 +2528,7 @@ struct device *genpd_dev_pm_attach_by_id(struct device *dev,
>  
>  	ret = device_register(virt_dev);
>  	if (ret) {
> -		kfree(virt_dev);
> +		put_device(virt_dev);
>  		return ERR_PTR(ret);
>  	}
>  
> -- 
> 2.17.1
> 

Acked-by: Niklas Cassel <niklas.cassel@linaro.org>

Re: [PATCH 2/3] PM / Domains: Allow OF lookup for multi PM domain case from ->attach_dev()

[Niklas Cassel]

On Thu, Apr 18, 2019 at 12:27:56PM +0200, Ulf Hansson wrote:
> A genpd provider that uses the ->attach_dev() callback to lookup resources
> for a device, fails to do so when the device has multiple PM domains. This
> is because when genpd invokes the ->attach_dev() callback, it passes the
> allocated virtual device as the in-parameter.
> 
> To address this problem, let's simply assign the dev->of_node for the
> virtual device, based upon the original device's OF node.
> 
> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
> ---
>  drivers/base/power/domain.c | 12 +++++++-----
>  1 file changed, 7 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> index 7fec69aebf46..801f31c87d16 100644
> --- a/drivers/base/power/domain.c
> +++ b/drivers/base/power/domain.c
> @@ -2345,6 +2345,7 @@ EXPORT_SYMBOL_GPL(of_genpd_remove_last);
>  
>  static void genpd_release_dev(struct device *dev)
>  {
> +	of_node_put(dev->of_node);
>  	kfree(dev);
>  }
>  
> @@ -2406,14 +2407,14 @@ static void genpd_dev_pm_sync(struct device *dev)
>  	genpd_queue_power_off_work(pd);
>  }
>  
> -static int __genpd_dev_pm_attach(struct device *dev, struct device_node *np,
> -				 unsigned int index, bool power_on)
> +static int __genpd_dev_pm_attach(struct device *dev, unsigned int index,
> +				 bool power_on)
>  {
>  	struct of_phandle_args pd_args;
>  	struct generic_pm_domain *pd;
>  	int ret;
>  
> -	ret = of_parse_phandle_with_args(np, "power-domains",
> +	ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
>  				"#power-domain-cells", index, &pd_args);
>  	if (ret < 0)
>  		return ret;
> @@ -2481,7 +2482,7 @@ int genpd_dev_pm_attach(struct device *dev)
>  				       "#power-domain-cells") != 1)
>  		return 0;
>  
> -	return __genpd_dev_pm_attach(dev, dev->of_node, 0, true);
> +	return __genpd_dev_pm_attach(dev, 0, true);
>  }
>  EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
>  
> @@ -2525,6 +2526,7 @@ struct device *genpd_dev_pm_attach_by_id(struct device *dev,
>  	dev_set_name(virt_dev, "genpd:%u:%s", index, dev_name(dev));
>  	virt_dev->bus = &genpd_bus_type;
>  	virt_dev->release = genpd_release_dev;
> +	virt_dev->of_node = of_node_get(dev->of_node);
>  
>  	ret = device_register(virt_dev);
>  	if (ret) {
> @@ -2533,7 +2535,7 @@ struct device *genpd_dev_pm_attach_by_id(struct device *dev,
>  	}
>  
>  	/* Try to attach the device to the PM domain at the specified index. */
> -	ret = __genpd_dev_pm_attach(virt_dev, dev->of_node, index, false);
> +	ret = __genpd_dev_pm_attach(virt_dev, index, false);
>  	if (ret < 1) {
>  		device_unregister(virt_dev);
>  		return ret ? ERR_PTR(ret) : NULL;
> -- 
> 2.17.1
> 

Acked-by: Niklas Cassel <niklas.cassel@linaro.org>

Re: [PATCH 3/3] PM / Domains: Enable genpd_dev_pm_attach_by_id|name() for single PM domain

[Niklas Cassel]

On Thu, Apr 18, 2019 at 12:27:57PM +0200, Ulf Hansson wrote:
> If a call to dev_pm_domain_attach() succeeds to attach a device to its
> single PM domain, the important point is to prevent following calls to

nit: s/prevent/ensure/

> dev_pm_domain_attach_by_name|id() to fail. This is managed by checking the
> dev->pm_domain pointer and then return -EEXIST, rather than continue
> calling genpd_dev_pm_attach_by_id|name().
> 
> For this reason, let's enable genpd_dev_pm_attach_by_id|name() to be used
> for also single PM domains. This simplifies for future users to solely make
> use of dev_pm_domain_attach_by_id|name() rather than having to combine it
> with dev_pm_domain_attach().
> 
> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
> ---
>  drivers/base/power/domain.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> index 801f31c87d16..1b026704a8fc 100644
> --- a/drivers/base/power/domain.c
> +++ b/drivers/base/power/domain.c
> @@ -2512,10 +2512,10 @@ struct device *genpd_dev_pm_attach_by_id(struct device *dev,
>  	if (!dev->of_node)
>  		return NULL;
>  
> -	/* Deal only with devices using multiple PM domains. */
> +	/* Verify that the index is within a valid range. */
>  	num_domains = of_count_phandle_with_args(dev->of_node, "power-domains",
>  						 "#power-domain-cells");
> -	if (num_domains < 2 || index >= num_domains)
> +	if (index >= num_domains)
>  		return NULL;
>  
>  	/* Allocate and register device on the genpd bus. */
> -- 
> 2.17.1
> 

Acked-by: Niklas Cassel <niklas.cassel@linaro.org>

Re: [PATCH 0/3] PM / Domains: Improve support for multi PM domains

[Rafael J. Wysocki]

On Thursday, April 18, 2019 12:27:54 PM CEST Ulf Hansson wrote:
> It's been a while since the introduction for the support for multi PM domains
> per device in genpd. In this small series, a couple of different improvement
> are being made to this code in genpd.
> 
> Ulf Hansson (3):
>   PM / Domains: Don't kfree() the virtual device in the error path
>   PM / Domains: Allow OF lookup for multi PM domain case from
>     ->attach_dev()
>   PM / Domains: Enable genpd_dev_pm_attach_by_id|name() for single PM
>     domain
> 
>  drivers/base/power/domain.c | 18 ++++++++++--------
>  1 file changed, 10 insertions(+), 8 deletions(-)

All [1-3/3] applied, thanks!