[PATCH v3 3/6] thermal/drivers/acpi: Use thermal_zone_device()

[PATCH v3 3/6] thermal/drivers/acpi: Use thermal_zone_device()

[Daniel Lezcano]

In order to get the device associated with the thermal zone, let's use
the wrapper thermal_zone_device() instead of accessing directly the
content of the thermal zone device structure.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/acpi/thermal.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
index 255efa73ed70..5763db4528b8 100644
--- a/drivers/acpi/thermal.c
+++ b/drivers/acpi/thermal.c
@@ -789,6 +789,7 @@ static struct thermal_zone_device_ops acpi_thermal_zone_ops = {
 
 static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
 {
+	struct device *tzdev;
 	int trips = 0;
 	int result;
 	acpi_status status;
@@ -820,12 +821,14 @@ static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
 	if (IS_ERR(tz->thermal_zone))
 		return -ENODEV;
 
+	tzdev = thermal_zone_device(tz->thermal_zone);
+	
 	result = sysfs_create_link(&tz->device->dev.kobj,
-				   &tz->thermal_zone->device.kobj, "thermal_zone");
+				   &tzdev->kobj, "thermal_zone");
 	if (result)
 		goto unregister_tzd;
 
-	result = sysfs_create_link(&tz->thermal_zone->device.kobj,
+	result = sysfs_create_link(&tzdev->kobj,
 				   &tz->device->dev.kobj, "device");
 	if (result)
 		goto remove_tz_link;
@@ -849,7 +852,7 @@ static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
 acpi_bus_detach:
 	acpi_bus_detach_private_data(tz->device->handle);
 remove_dev_link:
-	sysfs_remove_link(&tz->thermal_zone->device.kobj, "device");
+	sysfs_remove_link(&tzdev->kobj, "device");
 remove_tz_link:
 	sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
 unregister_tzd:
@@ -860,8 +863,10 @@ static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
 
 static void acpi_thermal_unregister_thermal_zone(struct acpi_thermal *tz)
 {
+	struct device *tzdev = thermal_zone_device(tz->thermal_zone);
+	
 	sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
-	sysfs_remove_link(&tz->thermal_zone->device.kobj, "device");
+	sysfs_remove_link(&tzdev->kobj, "device");
 	thermal_zone_device_unregister(tz->thermal_zone);
 	tz->thermal_zone = NULL;
 	acpi_bus_detach_private_data(tz->device->handle);
-- 
2.34.1

[PATCH v3 5/6] thermal/drivers/acpi: Make cross dev link optional by configuration

[Daniel Lezcano]

The ACPI thermal driver creates a link in the thermal zone device
sysfs directory pointing to the device sysfs directory. At the same
time, it creates a back pointer link from the device to the thermal
zone device sysfs directory.

From a generic perspective, having a device pointer in the sysfs
thermal zone directory may make sense. But the opposite is not true as
the same driver can be related to multiple thermal zones.

The usage of these information is very specific to ACPI and it is
questionable if they are really needed.

Let's make the code optional and disable it by default. If it hurts,
we will revert this change.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/acpi/Kconfig   | 13 +++++++++
 drivers/acpi/thermal.c | 62 ++++++++++++++++++++++++++++--------------
 2 files changed, 55 insertions(+), 20 deletions(-)

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index ccbeab9500ec..7df4e18f06ef 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -336,6 +336,19 @@ config ACPI_THERMAL
 	  To compile this driver as a module, choose M here:
 	  the module will be called thermal.
 
+config ACPI_THERMAL_SYSFS_ADDON
+       bool "Enable thermal sysfs addon"
+       depends on ACPI_THERMAL
+       def_bool n
+       help
+	 Enable sysfs extra information added in the thermal zone and
+	 the driver specific sysfs directories. That could be a link
+	 to the associated thermal zone as well as a link pointing to
+	 the device from the thermal zone. By default those are
+	 disabled and are candidate for removal, if you need these
+	 information anyway, enable the option or upgrade the
+	 userspace program using them.
+
 config ACPI_PLATFORM_PROFILE
 	tristate
 
diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
index 5763db4528b8..30fe189d04f8 100644
--- a/drivers/acpi/thermal.c
+++ b/drivers/acpi/thermal.c
@@ -787,9 +787,44 @@ static struct thermal_zone_device_ops acpi_thermal_zone_ops = {
 	.critical = acpi_thermal_zone_device_critical,
 };
 
+#ifdef CONFIG_ACPI_THERMAL_SYSFS_ADDON
+static int acpi_thermal_zone_sysfs_add(struct acpi_thermal *tz)
+{
+	struct device *tzdev = thermal_zone_device(tz->thermal_zone);
+	int ret;
+	
+	ret = sysfs_create_link(&tz->device->dev.kobj,
+				&tzdev->kobj, "thermal_zone");
+	if (ret)
+		return ret;
+
+	ret = sysfs_create_link(&tzdev->kobj,
+				   &tz->device->dev.kobj, "device");
+	if (ret)
+		sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
+
+	return ret;
+}
+
+static void acpi_thermal_zone_sysfs_remove(struct acpi_thermal *tz)
+{
+	struct device *tzdev = thermal_zone_device(tz->thermal_zone);
+	
+	sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
+	sysfs_remove_link(&tzdev->kobj, "device");
+}
+#else
+static inline int acpi_thermal_zone_sysfs_add(struct acpi_thermal *tz)
+{
+	return 0;
+}
+static inline void acpi_thermal_zone_sysfs_remove(struct acpi_thermal *tz)
+{
+}
+#endif
+
 static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
 {
-	struct device *tzdev;
 	int trips = 0;
 	int result;
 	acpi_status status;
@@ -821,23 +856,15 @@ static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
 	if (IS_ERR(tz->thermal_zone))
 		return -ENODEV;
 
-	tzdev = thermal_zone_device(tz->thermal_zone);
-	
-	result = sysfs_create_link(&tz->device->dev.kobj,
-				   &tzdev->kobj, "thermal_zone");
+	result = acpi_thermal_zone_sysfs_add(tz);
 	if (result)
 		goto unregister_tzd;
-
-	result = sysfs_create_link(&tzdev->kobj,
-				   &tz->device->dev.kobj, "device");
-	if (result)
-		goto remove_tz_link;
-
+	
 	status =  acpi_bus_attach_private_data(tz->device->handle,
 					       tz->thermal_zone);
 	if (ACPI_FAILURE(status)) {
 		result = -ENODEV;
-		goto remove_dev_link;
+		goto remove_links;
 	}
 
 	result = thermal_zone_device_enable(tz->thermal_zone);
@@ -851,10 +878,8 @@ static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
 
 acpi_bus_detach:
 	acpi_bus_detach_private_data(tz->device->handle);
-remove_dev_link:
-	sysfs_remove_link(&tzdev->kobj, "device");
-remove_tz_link:
-	sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
+remove_links:
+	acpi_thermal_zone_sysfs_remove(tz);
 unregister_tzd:
 	thermal_zone_device_unregister(tz->thermal_zone);
 
@@ -863,10 +888,7 @@ static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
 
 static void acpi_thermal_unregister_thermal_zone(struct acpi_thermal *tz)
 {
-	struct device *tzdev = thermal_zone_device(tz->thermal_zone);
-	
-	sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
-	sysfs_remove_link(&tzdev->kobj, "device");
+	acpi_thermal_zone_sysfs_remove(tz);
 	thermal_zone_device_unregister(tz->thermal_zone);
 	tz->thermal_zone = NULL;
 	acpi_bus_detach_private_data(tz->device->handle);
-- 
2.34.1

Re: [PATCH v3 5/6] thermal/drivers/acpi: Make cross dev link optional by configuration

[Rafael J. Wysocki]

On Thu, Apr 13, 2023 at 1:47 PM Daniel Lezcano
<daniel.lezcano@linaro.org> wrote:
>
> The ACPI thermal driver creates a link in the thermal zone device
> sysfs directory pointing to the device sysfs directory. At the same
> time, it creates a back pointer link from the device to the thermal
> zone device sysfs directory.
>
> From a generic perspective, having a device pointer in the sysfs
> thermal zone directory may make sense. But the opposite is not true as
> the same driver can be related to multiple thermal zones.
>
> The usage of these information is very specific to ACPI and it is
> questionable if they are really needed.
>
> Let's make the code optional and disable it by default. If it hurts,
> we will revert this change.
>
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> ---
>  drivers/acpi/Kconfig   | 13 +++++++++
>  drivers/acpi/thermal.c | 62 ++++++++++++++++++++++++++++--------------
>  2 files changed, 55 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
> index ccbeab9500ec..7df4e18f06ef 100644
> --- a/drivers/acpi/Kconfig
> +++ b/drivers/acpi/Kconfig
> @@ -336,6 +336,19 @@ config ACPI_THERMAL
>           To compile this driver as a module, choose M here:
>           the module will be called thermal.
>
> +config ACPI_THERMAL_SYSFS_ADDON
> +       bool "Enable thermal sysfs addon"
> +       depends on ACPI_THERMAL
> +       def_bool n
> +       help
> +        Enable sysfs extra information added in the thermal zone and
> +        the driver specific sysfs directories. That could be a link
> +        to the associated thermal zone as well as a link pointing to
> +        the device from the thermal zone. By default those are
> +        disabled and are candidate for removal, if you need these
> +        information anyway, enable the option or upgrade the
> +        userspace program using them.
> +

I don't think that the Kconfig option is appropriate and the help text
above isn't really helpful.

>  config ACPI_PLATFORM_PROFILE
>         tristate
>
> diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
> index 5763db4528b8..30fe189d04f8 100644
> --- a/drivers/acpi/thermal.c
> +++ b/drivers/acpi/thermal.c
> @@ -787,9 +787,44 @@ static struct thermal_zone_device_ops acpi_thermal_zone_ops = {
>         .critical = acpi_thermal_zone_device_critical,
>  };
>
> +#ifdef CONFIG_ACPI_THERMAL_SYSFS_ADDON

I agree with moving the code in question to separate functions, but I
don't agree with putting it under the Kconfig option.

> +static int acpi_thermal_zone_sysfs_add(struct acpi_thermal *tz)
> +{
> +       struct device *tzdev = thermal_zone_device(tz->thermal_zone);
> +       int ret;
> +
> +       ret = sysfs_create_link(&tz->device->dev.kobj,
> +                               &tzdev->kobj, "thermal_zone");
> +       if (ret)
> +               return ret;
> +
> +       ret = sysfs_create_link(&tzdev->kobj,
> +                                  &tz->device->dev.kobj, "device");
> +       if (ret)
> +               sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
> +
> +       return ret;
> +}
> +
> +static void acpi_thermal_zone_sysfs_remove(struct acpi_thermal *tz)
> +{
> +       struct device *tzdev = thermal_zone_device(tz->thermal_zone);
> +
> +       sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
> +       sysfs_remove_link(&tzdev->kobj, "device");
> +}
> +#else
> +static inline int acpi_thermal_zone_sysfs_add(struct acpi_thermal *tz)
> +{
> +       return 0;
> +}
> +static inline void acpi_thermal_zone_sysfs_remove(struct acpi_thermal *tz)
> +{
> +}
> +#endif
> +
>  static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
>  {
> -       struct device *tzdev;
>         int trips = 0;
>         int result;
>         acpi_status status;
> @@ -821,23 +856,15 @@ static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
>         if (IS_ERR(tz->thermal_zone))
>                 return -ENODEV;
>
> -       tzdev = thermal_zone_device(tz->thermal_zone);
> -
> -       result = sysfs_create_link(&tz->device->dev.kobj,
> -                                  &tzdev->kobj, "thermal_zone");
> +       result = acpi_thermal_zone_sysfs_add(tz);
>         if (result)
>                 goto unregister_tzd;
> -
> -       result = sysfs_create_link(&tzdev->kobj,
> -                                  &tz->device->dev.kobj, "device");
> -       if (result)
> -               goto remove_tz_link;
> -
> +
>         status =  acpi_bus_attach_private_data(tz->device->handle,
>                                                tz->thermal_zone);
>         if (ACPI_FAILURE(status)) {
>                 result = -ENODEV;
> -               goto remove_dev_link;
> +               goto remove_links;
>         }
>
>         result = thermal_zone_device_enable(tz->thermal_zone);
> @@ -851,10 +878,8 @@ static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
>
>  acpi_bus_detach:
>         acpi_bus_detach_private_data(tz->device->handle);
> -remove_dev_link:
> -       sysfs_remove_link(&tzdev->kobj, "device");
> -remove_tz_link:
> -       sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
> +remove_links:
> +       acpi_thermal_zone_sysfs_remove(tz);
>  unregister_tzd:
>         thermal_zone_device_unregister(tz->thermal_zone);
>
> @@ -863,10 +888,7 @@ static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
>
>  static void acpi_thermal_unregister_thermal_zone(struct acpi_thermal *tz)
>  {
> -       struct device *tzdev = thermal_zone_device(tz->thermal_zone);
> -
> -       sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
> -       sysfs_remove_link(&tzdev->kobj, "device");
> +       acpi_thermal_zone_sysfs_remove(tz);
>         thermal_zone_device_unregister(tz->thermal_zone);
>         tz->thermal_zone = NULL;
>         acpi_bus_detach_private_data(tz->device->handle);
> --
> 2.34.1
>

Re: [PATCH v3 5/6] thermal/drivers/acpi: Make cross dev link optional by configuration

[Daniel Lezcano]

On 18/04/2023 15:38, Rafael J. Wysocki wrote:
> On Thu, Apr 13, 2023 at 1:47 PM Daniel Lezcano
> <daniel.lezcano@linaro.org> wrote:
>>
>> The ACPI thermal driver creates a link in the thermal zone device
>> sysfs directory pointing to the device sysfs directory. At the same
>> time, it creates a back pointer link from the device to the thermal
>> zone device sysfs directory.
>>
>>  From a generic perspective, having a device pointer in the sysfs
>> thermal zone directory may make sense. But the opposite is not true as
>> the same driver can be related to multiple thermal zones.
>>
>> The usage of these information is very specific to ACPI and it is
>> questionable if they are really needed.
>>
>> Let's make the code optional and disable it by default. If it hurts,
>> we will revert this change.
>>
>> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
>> ---
>>   drivers/acpi/Kconfig   | 13 +++++++++
>>   drivers/acpi/thermal.c | 62 ++++++++++++++++++++++++++++--------------
>>   2 files changed, 55 insertions(+), 20 deletions(-)
>>
>> diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
>> index ccbeab9500ec..7df4e18f06ef 100644
>> --- a/drivers/acpi/Kconfig
>> +++ b/drivers/acpi/Kconfig
>> @@ -336,6 +336,19 @@ config ACPI_THERMAL
>>            To compile this driver as a module, choose M here:
>>            the module will be called thermal.
>>
>> +config ACPI_THERMAL_SYSFS_ADDON
>> +       bool "Enable thermal sysfs addon"
>> +       depends on ACPI_THERMAL
>> +       def_bool n
>> +       help
>> +        Enable sysfs extra information added in the thermal zone and
>> +        the driver specific sysfs directories. That could be a link
>> +        to the associated thermal zone as well as a link pointing to
>> +        the device from the thermal zone. By default those are
>> +        disabled and are candidate for removal, if you need these
>> +        information anyway, enable the option or upgrade the
>> +        userspace program using them.
>> +
> 
> I don't think that the Kconfig option is appropriate and the help text
> above isn't really helpful.

I'm sorry, I'm missing something. Don't we want to make these sysfs 
extra information optional and disable them by default ?

>>   config ACPI_PLATFORM_PROFILE
>>          tristate
>>
>> diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
>> index 5763db4528b8..30fe189d04f8 100644
>> --- a/drivers/acpi/thermal.c
>> +++ b/drivers/acpi/thermal.c
>> @@ -787,9 +787,44 @@ static struct thermal_zone_device_ops acpi_thermal_zone_ops = {
>>          .critical = acpi_thermal_zone_device_critical,
>>   };
>>
>> +#ifdef CONFIG_ACPI_THERMAL_SYSFS_ADDON
> 
> I agree with moving the code in question to separate functions, but I
> don't agree with putting it under the Kconfig option.

Do you mean use IS_ENABLED check like what is done with Menlow patch 6 ?

[ ... ]


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Re: [PATCH v3 5/6] thermal/drivers/acpi: Make cross dev link optional by configuration

[Rafael J. Wysocki]

On Tue, Apr 18, 2023 at 3:44 PM Daniel Lezcano
<daniel.lezcano@linaro.org> wrote:
>
> On 18/04/2023 15:38, Rafael J. Wysocki wrote:
> > On Thu, Apr 13, 2023 at 1:47 PM Daniel Lezcano
> > <daniel.lezcano@linaro.org> wrote:
> >>
> >> The ACPI thermal driver creates a link in the thermal zone device
> >> sysfs directory pointing to the device sysfs directory. At the same
> >> time, it creates a back pointer link from the device to the thermal
> >> zone device sysfs directory.
> >>
> >>  From a generic perspective, having a device pointer in the sysfs
> >> thermal zone directory may make sense. But the opposite is not true as
> >> the same driver can be related to multiple thermal zones.
> >>
> >> The usage of these information is very specific to ACPI and it is
> >> questionable if they are really needed.
> >>
> >> Let's make the code optional and disable it by default. If it hurts,
> >> we will revert this change.
> >>
> >> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> >> ---
> >>   drivers/acpi/Kconfig   | 13 +++++++++
> >>   drivers/acpi/thermal.c | 62 ++++++++++++++++++++++++++++--------------
> >>   2 files changed, 55 insertions(+), 20 deletions(-)
> >>
> >> diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
> >> index ccbeab9500ec..7df4e18f06ef 100644
> >> --- a/drivers/acpi/Kconfig
> >> +++ b/drivers/acpi/Kconfig
> >> @@ -336,6 +336,19 @@ config ACPI_THERMAL
> >>            To compile this driver as a module, choose M here:
> >>            the module will be called thermal.
> >>
> >> +config ACPI_THERMAL_SYSFS_ADDON
> >> +       bool "Enable thermal sysfs addon"
> >> +       depends on ACPI_THERMAL
> >> +       def_bool n
> >> +       help
> >> +        Enable sysfs extra information added in the thermal zone and
> >> +        the driver specific sysfs directories. That could be a link
> >> +        to the associated thermal zone as well as a link pointing to
> >> +        the device from the thermal zone. By default those are
> >> +        disabled and are candidate for removal, if you need these
> >> +        information anyway, enable the option or upgrade the
> >> +        userspace program using them.
> >> +
> >
> > I don't think that the Kconfig option is appropriate and the help text
> > above isn't really helpful.
>
> I'm sorry, I'm missing something. Don't we want to make these sysfs
> extra information optional and disable them by default ?

No, I mean no Kconfig option at all for this one at least for now.

Re: [PATCH v3 5/6] thermal/drivers/acpi: Make cross dev link optional by configuration

[Daniel Lezcano]

On 18/04/2023 15:47, Rafael J. Wysocki wrote:

[ ... ]

>> I'm sorry, I'm missing something. Don't we want to make these sysfs
>> extra information optional and disable them by default ?
> 
> No, I mean no Kconfig option at all for this one at least for now.

Ok, got it

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