[PATCH 1/3] video / backlight: add two APIs for drivers to use

[PATCH 1/3] video / backlight: add two APIs for drivers to use

[Aaron Lu]

It is useful to get the backlight device's pointer and use it to set
backlight in some cases(the following patch will make use of it) so add
the two APIs and export them.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
---
 drivers/video/backlight/backlight.c | 44 ++++++++++++++++++++++++-------------
 include/linux/backlight.h           |  2 ++
 2 files changed, 31 insertions(+), 15 deletions(-)

diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
index bddc8b17a4d8..bea749329236 100644
--- a/drivers/video/backlight/backlight.c
+++ b/drivers/video/backlight/backlight.c
@@ -164,28 +164,19 @@ static ssize_t brightness_show(struct device *dev,
 	return sprintf(buf, "%d\n", bd->props.brightness);
 }
 
-static ssize_t brightness_store(struct device *dev,
-		struct device_attribute *attr, const char *buf, size_t count)
+int backlight_device_set_brightness(struct backlight_device *bd, int brightness)
 {
-	int rc;
-	struct backlight_device *bd = to_backlight_device(dev);
-	unsigned long brightness;
-
-	rc = kstrtoul(buf, 0, &brightness);
-	if (rc)
-		return rc;
-
-	rc = -ENXIO;
+	int rc = -ENXIO;
 
 	mutex_lock(&bd->ops_lock);
 	if (bd->ops) {
 		if (brightness > bd->props.max_brightness)
 			rc = -EINVAL;
 		else {
-			pr_debug("set brightness to %lu\n", brightness);
+			pr_debug("set brightness to %u\n", brightness);
 			bd->props.brightness = brightness;
 			backlight_update_status(bd);
-			rc = count;
+			rc = 0;
 		}
 	}
 	mutex_unlock(&bd->ops_lock);
@@ -194,6 +185,23 @@ static ssize_t brightness_store(struct device *dev,
 
 	return rc;
 }
+EXPORT_SYMBOL(backlight_device_set_brightness);
+
+static ssize_t brightness_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	int rc;
+	struct backlight_device *bd = to_backlight_device(dev);
+	unsigned long brightness;
+
+	rc = kstrtoul(buf, 0, &brightness);
+	if (rc)
+		return rc;
+
+	rc = backlight_device_set_brightness(bd, brightness);
+
+	return rc ? rc : count;
+}
 static DEVICE_ATTR_RW(brightness);
 
 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
@@ -380,7 +388,7 @@ struct backlight_device *backlight_device_register(const char *name,
 }
 EXPORT_SYMBOL(backlight_device_register);
 
-bool backlight_device_registered(enum backlight_type type)
+struct backlight_device *backlight_device_get_by_type(enum backlight_type type)
 {
 	bool found = false;
 	struct backlight_device *bd;
@@ -394,7 +402,13 @@ bool backlight_device_registered(enum backlight_type type)
 	}
 	mutex_unlock(&backlight_dev_list_mutex);
 
-	return found;
+	return found ? bd : NULL;
+}
+EXPORT_SYMBOL(backlight_device_get_by_type);
+
+bool backlight_device_registered(enum backlight_type type)
+{
+	return backlight_device_get_by_type(type) ? true : false;
 }
 EXPORT_SYMBOL(backlight_device_registered);
 
diff --git a/include/linux/backlight.h b/include/linux/backlight.h
index adb14a8616df..c59a020df3f8 100644
--- a/include/linux/backlight.h
+++ b/include/linux/backlight.h
@@ -140,6 +140,8 @@ extern void backlight_force_update(struct backlight_device *bd,
 extern bool backlight_device_registered(enum backlight_type type);
 extern int backlight_register_notifier(struct notifier_block *nb);
 extern int backlight_unregister_notifier(struct notifier_block *nb);
+extern struct backlight_device *backlight_device_get_by_type(enum backlight_type type);
+extern int backlight_device_set_brightness(struct backlight_device *bd, int brightness);
 
 #define to_backlight_device(obj) container_of(obj, struct backlight_device, dev)
 
-- 
2.1.0

Re: [PATCH 1/3] video / backlight: add two APIs for drivers to use

[Jingoo Han]

On Wednesday, December 31, 2014 12:50 PM, Aaron Lu wrote:
> 
> It is useful to get the backlight device's pointer and use it to set
> backlight in some cases(the following patch will make use of it) so add
> the two APIs and export them.
> 
> Signed-off-by: Aaron Lu <aaron.lu@intel.com>

Acked-by: Jingoo Han <jg1.han@samsung.com>

Best regards,
Jingoo Han

> ---
>  drivers/video/backlight/backlight.c | 44 ++++++++++++++++++++++++-------------
>  include/linux/backlight.h           |  2 ++
>  2 files changed, 31 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
> index bddc8b17a4d8..bea749329236 100644
> --- a/drivers/video/backlight/backlight.c
> +++ b/drivers/video/backlight/backlight.c
> @@ -164,28 +164,19 @@ static ssize_t brightness_show(struct device *dev,
>  	return sprintf(buf, "%d\n", bd->props.brightness);
>  }
> 
> -static ssize_t brightness_store(struct device *dev,
> -		struct device_attribute *attr, const char *buf, size_t count)
> +int backlight_device_set_brightness(struct backlight_device *bd, int brightness)
>  {
> -	int rc;
> -	struct backlight_device *bd = to_backlight_device(dev);
> -	unsigned long brightness;
> -
> -	rc = kstrtoul(buf, 0, &brightness);
> -	if (rc)
> -		return rc;
> -
> -	rc = -ENXIO;
> +	int rc = -ENXIO;
> 
>  	mutex_lock(&bd->ops_lock);
>  	if (bd->ops) {
>  		if (brightness > bd->props.max_brightness)
>  			rc = -EINVAL;
>  		else {
> -			pr_debug("set brightness to %lu\n", brightness);
> +			pr_debug("set brightness to %u\n", brightness);
>  			bd->props.brightness = brightness;
>  			backlight_update_status(bd);
> -			rc = count;
> +			rc = 0;
>  		}
>  	}
>  	mutex_unlock(&bd->ops_lock);
> @@ -194,6 +185,23 @@ static ssize_t brightness_store(struct device *dev,
> 
>  	return rc;
>  }
> +EXPORT_SYMBOL(backlight_device_set_brightness);
> +
> +static ssize_t brightness_store(struct device *dev,
> +		struct device_attribute *attr, const char *buf, size_t count)
> +{
> +	int rc;
> +	struct backlight_device *bd = to_backlight_device(dev);
> +	unsigned long brightness;
> +
> +	rc = kstrtoul(buf, 0, &brightness);
> +	if (rc)
> +		return rc;
> +
> +	rc = backlight_device_set_brightness(bd, brightness);
> +
> +	return rc ? rc : count;
> +}
>  static DEVICE_ATTR_RW(brightness);
> 
>  static ssize_t type_show(struct device *dev, struct device_attribute *attr,
> @@ -380,7 +388,7 @@ struct backlight_device *backlight_device_register(const char *name,
>  }
>  EXPORT_SYMBOL(backlight_device_register);
> 
> -bool backlight_device_registered(enum backlight_type type)
> +struct backlight_device *backlight_device_get_by_type(enum backlight_type type)
>  {
>  	bool found = false;
>  	struct backlight_device *bd;
> @@ -394,7 +402,13 @@ bool backlight_device_registered(enum backlight_type type)
>  	}
>  	mutex_unlock(&backlight_dev_list_mutex);
> 
> -	return found;
> +	return found ? bd : NULL;
> +}
> +EXPORT_SYMBOL(backlight_device_get_by_type);
> +
> +bool backlight_device_registered(enum backlight_type type)
> +{
> +	return backlight_device_get_by_type(type) ? true : false;
>  }
>  EXPORT_SYMBOL(backlight_device_registered);
> 
> diff --git a/include/linux/backlight.h b/include/linux/backlight.h
> index adb14a8616df..c59a020df3f8 100644
> --- a/include/linux/backlight.h
> +++ b/include/linux/backlight.h
> @@ -140,6 +140,8 @@ extern void backlight_force_update(struct backlight_device *bd,
>  extern bool backlight_device_registered(enum backlight_type type);
>  extern int backlight_register_notifier(struct notifier_block *nb);
>  extern int backlight_unregister_notifier(struct notifier_block *nb);
> +extern struct backlight_device *backlight_device_get_by_type(enum backlight_type type);
> +extern int backlight_device_set_brightness(struct backlight_device *bd, int brightness);
> 
>  #define to_backlight_device(obj) container_of(obj, struct backlight_device, dev)
> 
> --
> 2.1.0

Re: [PATCH 1/3] video / backlight: add two APIs for drivers to use

[Aaron Lu]

On 01/03/2015 09:04 AM, Jingoo Han wrote:
> On Wednesday, December 31, 2014 12:50 PM, Aaron Lu wrote:
>>
>> It is useful to get the backlight device's pointer and use it to set
>> backlight in some cases(the following patch will make use of it) so add
>> the two APIs and export them.
>>
>> Signed-off-by: Aaron Lu <aaron.lu@intel.com>
> 
> Acked-by: Jingoo Han <jg1.han@samsung.com>

Thanks for the review!

Regards,
Aaron

> 
> Best regards,
> Jingoo Han
> 
>> ---
>>  drivers/video/backlight/backlight.c | 44 ++++++++++++++++++++++++-------------
>>  include/linux/backlight.h           |  2 ++
>>  2 files changed, 31 insertions(+), 15 deletions(-)
>>
>> diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
>> index bddc8b17a4d8..bea749329236 100644
>> --- a/drivers/video/backlight/backlight.c
>> +++ b/drivers/video/backlight/backlight.c
>> @@ -164,28 +164,19 @@ static ssize_t brightness_show(struct device *dev,
>>  	return sprintf(buf, "%d\n", bd->props.brightness);
>>  }
>>
>> -static ssize_t brightness_store(struct device *dev,
>> -		struct device_attribute *attr, const char *buf, size_t count)
>> +int backlight_device_set_brightness(struct backlight_device *bd, int brightness)
>>  {
>> -	int rc;
>> -	struct backlight_device *bd = to_backlight_device(dev);
>> -	unsigned long brightness;
>> -
>> -	rc = kstrtoul(buf, 0, &brightness);
>> -	if (rc)
>> -		return rc;
>> -
>> -	rc = -ENXIO;
>> +	int rc = -ENXIO;
>>
>>  	mutex_lock(&bd->ops_lock);
>>  	if (bd->ops) {
>>  		if (brightness > bd->props.max_brightness)
>>  			rc = -EINVAL;
>>  		else {
>> -			pr_debug("set brightness to %lu\n", brightness);
>> +			pr_debug("set brightness to %u\n", brightness);
>>  			bd->props.brightness = brightness;
>>  			backlight_update_status(bd);
>> -			rc = count;
>> +			rc = 0;
>>  		}
>>  	}
>>  	mutex_unlock(&bd->ops_lock);
>> @@ -194,6 +185,23 @@ static ssize_t brightness_store(struct device *dev,
>>
>>  	return rc;
>>  }
>> +EXPORT_SYMBOL(backlight_device_set_brightness);
>> +
>> +static ssize_t brightness_store(struct device *dev,
>> +		struct device_attribute *attr, const char *buf, size_t count)
>> +{
>> +	int rc;
>> +	struct backlight_device *bd = to_backlight_device(dev);
>> +	unsigned long brightness;
>> +
>> +	rc = kstrtoul(buf, 0, &brightness);
>> +	if (rc)
>> +		return rc;
>> +
>> +	rc = backlight_device_set_brightness(bd, brightness);
>> +
>> +	return rc ? rc : count;
>> +}
>>  static DEVICE_ATTR_RW(brightness);
>>
>>  static ssize_t type_show(struct device *dev, struct device_attribute *attr,
>> @@ -380,7 +388,7 @@ struct backlight_device *backlight_device_register(const char *name,
>>  }
>>  EXPORT_SYMBOL(backlight_device_register);
>>
>> -bool backlight_device_registered(enum backlight_type type)
>> +struct backlight_device *backlight_device_get_by_type(enum backlight_type type)
>>  {
>>  	bool found = false;
>>  	struct backlight_device *bd;
>> @@ -394,7 +402,13 @@ bool backlight_device_registered(enum backlight_type type)
>>  	}
>>  	mutex_unlock(&backlight_dev_list_mutex);
>>
>> -	return found;
>> +	return found ? bd : NULL;
>> +}
>> +EXPORT_SYMBOL(backlight_device_get_by_type);
>> +
>> +bool backlight_device_registered(enum backlight_type type)
>> +{
>> +	return backlight_device_get_by_type(type) ? true : false;
>>  }
>>  EXPORT_SYMBOL(backlight_device_registered);
>>
>> diff --git a/include/linux/backlight.h b/include/linux/backlight.h
>> index adb14a8616df..c59a020df3f8 100644
>> --- a/include/linux/backlight.h
>> +++ b/include/linux/backlight.h
>> @@ -140,6 +140,8 @@ extern void backlight_force_update(struct backlight_device *bd,
>>  extern bool backlight_device_registered(enum backlight_type type);
>>  extern int backlight_register_notifier(struct notifier_block *nb);
>>  extern int backlight_unregister_notifier(struct notifier_block *nb);
>> +extern struct backlight_device *backlight_device_get_by_type(enum backlight_type type);
>> +extern int backlight_device_set_brightness(struct backlight_device *bd, int brightness);
>>
>>  #define to_backlight_device(obj) container_of(obj, struct backlight_device, dev)
>>
>> --
>> 2.1.0
> 

Re: [PATCH 1/3] video / backlight: add two APIs for drivers to use

[Zhang Rui]

On Mon, 2015-01-05 at 13:46 +0800, Aaron Lu wrote:
> On 01/03/2015 09:04 AM, Jingoo Han wrote:
> > On Wednesday, December 31, 2014 12:50 PM, Aaron Lu wrote:
> >>
> >> It is useful to get the backlight device's pointer and use it to set
> >> backlight in some cases(the following patch will make use of it) so add
> >> the two APIs and export them.
> >>
> >> Signed-off-by: Aaron Lu <aaron.lu@intel.com>
> > 
> > Acked-by: Jingoo Han <jg1.han@samsung.com>
> 
So Jingoo and Lee, will you take the first two patches, or you'd like me
the take the whole patch set?

thanks,
rui
> Thanks for the review!
> 
> Regards,
> Aaron
> 
> > 
> > Best regards,
> > Jingoo Han
> > 
> >> ---
> >>  drivers/video/backlight/backlight.c | 44 ++++++++++++++++++++++++-------------
> >>  include/linux/backlight.h           |  2 ++
> >>  2 files changed, 31 insertions(+), 15 deletions(-)
> >>
> >> diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
> >> index bddc8b17a4d8..bea749329236 100644
> >> --- a/drivers/video/backlight/backlight.c
> >> +++ b/drivers/video/backlight/backlight.c
> >> @@ -164,28 +164,19 @@ static ssize_t brightness_show(struct device *dev,
> >>  	return sprintf(buf, "%d\n", bd->props.brightness);
> >>  }
> >>
> >> -static ssize_t brightness_store(struct device *dev,
> >> -		struct device_attribute *attr, const char *buf, size_t count)
> >> +int backlight_device_set_brightness(struct backlight_device *bd, int brightness)
> >>  {
> >> -	int rc;
> >> -	struct backlight_device *bd = to_backlight_device(dev);
> >> -	unsigned long brightness;
> >> -
> >> -	rc = kstrtoul(buf, 0, &brightness);
> >> -	if (rc)
> >> -		return rc;
> >> -
> >> -	rc = -ENXIO;
> >> +	int rc = -ENXIO;
> >>
> >>  	mutex_lock(&bd->ops_lock);
> >>  	if (bd->ops) {
> >>  		if (brightness > bd->props.max_brightness)
> >>  			rc = -EINVAL;
> >>  		else {
> >> -			pr_debug("set brightness to %lu\n", brightness);
> >> +			pr_debug("set brightness to %u\n", brightness);
> >>  			bd->props.brightness = brightness;
> >>  			backlight_update_status(bd);
> >> -			rc = count;
> >> +			rc = 0;
> >>  		}
> >>  	}
> >>  	mutex_unlock(&bd->ops_lock);
> >> @@ -194,6 +185,23 @@ static ssize_t brightness_store(struct device *dev,
> >>
> >>  	return rc;
> >>  }
> >> +EXPORT_SYMBOL(backlight_device_set_brightness);
> >> +
> >> +static ssize_t brightness_store(struct device *dev,
> >> +		struct device_attribute *attr, const char *buf, size_t count)
> >> +{
> >> +	int rc;
> >> +	struct backlight_device *bd = to_backlight_device(dev);
> >> +	unsigned long brightness;
> >> +
> >> +	rc = kstrtoul(buf, 0, &brightness);
> >> +	if (rc)
> >> +		return rc;
> >> +
> >> +	rc = backlight_device_set_brightness(bd, brightness);
> >> +
> >> +	return rc ? rc : count;
> >> +}
> >>  static DEVICE_ATTR_RW(brightness);
> >>
> >>  static ssize_t type_show(struct device *dev, struct device_attribute *attr,
> >> @@ -380,7 +388,7 @@ struct backlight_device *backlight_device_register(const char *name,
> >>  }
> >>  EXPORT_SYMBOL(backlight_device_register);
> >>
> >> -bool backlight_device_registered(enum backlight_type type)
> >> +struct backlight_device *backlight_device_get_by_type(enum backlight_type type)
> >>  {
> >>  	bool found = false;
> >>  	struct backlight_device *bd;
> >> @@ -394,7 +402,13 @@ bool backlight_device_registered(enum backlight_type type)
> >>  	}
> >>  	mutex_unlock(&backlight_dev_list_mutex);
> >>
> >> -	return found;
> >> +	return found ? bd : NULL;
> >> +}
> >> +EXPORT_SYMBOL(backlight_device_get_by_type);
> >> +
> >> +bool backlight_device_registered(enum backlight_type type)
> >> +{
> >> +	return backlight_device_get_by_type(type) ? true : false;
> >>  }
> >>  EXPORT_SYMBOL(backlight_device_registered);
> >>
> >> diff --git a/include/linux/backlight.h b/include/linux/backlight.h
> >> index adb14a8616df..c59a020df3f8 100644
> >> --- a/include/linux/backlight.h
> >> +++ b/include/linux/backlight.h
> >> @@ -140,6 +140,8 @@ extern void backlight_force_update(struct backlight_device *bd,
> >>  extern bool backlight_device_registered(enum backlight_type type);
> >>  extern int backlight_register_notifier(struct notifier_block *nb);
> >>  extern int backlight_unregister_notifier(struct notifier_block *nb);
> >> +extern struct backlight_device *backlight_device_get_by_type(enum backlight_type type);
> >> +extern int backlight_device_set_brightness(struct backlight_device *bd, int brightness);
> >>
> >>  #define to_backlight_device(obj) container_of(obj, struct backlight_device, dev)
> >>
> >> --
> >> 2.1.0
> > 
> 

Re: [PATCH 1/3] video / backlight: add two APIs for drivers to use

[Jingoo Han]

On Monday, January 05, 2015 3:01 PM, Zhang Rui wrote:
> On Mon, 2015-01-05 at 13:46 +0800, Aaron Lu wrote:
> > On 01/03/2015 09:04 AM, Jingoo Han wrote:
> > > On Wednesday, December 31, 2014 12:50 PM, Aaron Lu wrote:
> > >>
> > >> It is useful to get the backlight device's pointer and use it to set
> > >> backlight in some cases(the following patch will make use of it) so add
> > >> the two APIs and export them.
> > >>
> > >> Signed-off-by: Aaron Lu <aaron.lu@intel.com>
> > >
> > > Acked-by: Jingoo Han <jg1.han@samsung.com>
> >
> So Jingoo and Lee, will you take the first two patches, or you'd like me
> the take the whole patch set?

Hi Zhang Rui,

I would like you to take the whole patch set.
This is because 3rd patch makes the build error
without 1st & 2nd patches. Thank you.

Best regards,
Jingoo Han

> 
> thanks,
> rui
> > Thanks for the review!
> >
> > Regards,
> > Aaron
> >
> > >
> > > Best regards,
> > > Jingoo Han
> > >
> > >> ---
> > >>  drivers/video/backlight/backlight.c | 44 ++++++++++++++++++++++++-------------
> > >>  include/linux/backlight.h           |  2 ++
> > >>  2 files changed, 31 insertions(+), 15 deletions(-)
> > >>
> > >> diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
> > >> index bddc8b17a4d8..bea749329236 100644
> > >> --- a/drivers/video/backlight/backlight.c
> > >> +++ b/drivers/video/backlight/backlight.c
> > >> @@ -164,28 +164,19 @@ static ssize_t brightness_show(struct device *dev,
> > >>  	return sprintf(buf, "%d\n", bd->props.brightness);
> > >>  }
> > >>
> > >> -static ssize_t brightness_store(struct device *dev,
> > >> -		struct device_attribute *attr, const char *buf, size_t count)
> > >> +int backlight_device_set_brightness(struct backlight_device *bd, int brightness)
> > >>  {
> > >> -	int rc;
> > >> -	struct backlight_device *bd = to_backlight_device(dev);
> > >> -	unsigned long brightness;
> > >> -
> > >> -	rc = kstrtoul(buf, 0, &brightness);
> > >> -	if (rc)
> > >> -		return rc;
> > >> -
> > >> -	rc = -ENXIO;
> > >> +	int rc = -ENXIO;
> > >>
> > >>  	mutex_lock(&bd->ops_lock);
> > >>  	if (bd->ops) {
> > >>  		if (brightness > bd->props.max_brightness)
> > >>  			rc = -EINVAL;
> > >>  		else {
> > >> -			pr_debug("set brightness to %lu\n", brightness);
> > >> +			pr_debug("set brightness to %u\n", brightness);
> > >>  			bd->props.brightness = brightness;
> > >>  			backlight_update_status(bd);
> > >> -			rc = count;
> > >> +			rc = 0;
> > >>  		}
> > >>  	}
> > >>  	mutex_unlock(&bd->ops_lock);
> > >> @@ -194,6 +185,23 @@ static ssize_t brightness_store(struct device *dev,
> > >>
> > >>  	return rc;
> > >>  }
> > >> +EXPORT_SYMBOL(backlight_device_set_brightness);
> > >> +
> > >> +static ssize_t brightness_store(struct device *dev,
> > >> +		struct device_attribute *attr, const char *buf, size_t count)
> > >> +{
> > >> +	int rc;
> > >> +	struct backlight_device *bd = to_backlight_device(dev);
> > >> +	unsigned long brightness;
> > >> +
> > >> +	rc = kstrtoul(buf, 0, &brightness);
> > >> +	if (rc)
> > >> +		return rc;
> > >> +
> > >> +	rc = backlight_device_set_brightness(bd, brightness);
> > >> +
> > >> +	return rc ? rc : count;
> > >> +}
> > >>  static DEVICE_ATTR_RW(brightness);
> > >>
> > >>  static ssize_t type_show(struct device *dev, struct device_attribute *attr,
> > >> @@ -380,7 +388,7 @@ struct backlight_device *backlight_device_register(const char *name,
> > >>  }
> > >>  EXPORT_SYMBOL(backlight_device_register);
> > >>
> > >> -bool backlight_device_registered(enum backlight_type type)
> > >> +struct backlight_device *backlight_device_get_by_type(enum backlight_type type)
> > >>  {
> > >>  	bool found = false;
> > >>  	struct backlight_device *bd;
> > >> @@ -394,7 +402,13 @@ bool backlight_device_registered(enum backlight_type type)
> > >>  	}
> > >>  	mutex_unlock(&backlight_dev_list_mutex);
> > >>
> > >> -	return found;
> > >> +	return found ? bd : NULL;
> > >> +}
> > >> +EXPORT_SYMBOL(backlight_device_get_by_type);
> > >> +
> > >> +bool backlight_device_registered(enum backlight_type type)
> > >> +{
> > >> +	return backlight_device_get_by_type(type) ? true : false;
> > >>  }
> > >>  EXPORT_SYMBOL(backlight_device_registered);
> > >>
> > >> diff --git a/include/linux/backlight.h b/include/linux/backlight.h
> > >> index adb14a8616df..c59a020df3f8 100644
> > >> --- a/include/linux/backlight.h
> > >> +++ b/include/linux/backlight.h
> > >> @@ -140,6 +140,8 @@ extern void backlight_force_update(struct backlight_device *bd,
> > >>  extern bool backlight_device_registered(enum backlight_type type);
> > >>  extern int backlight_register_notifier(struct notifier_block *nb);
> > >>  extern int backlight_unregister_notifier(struct notifier_block *nb);
> > >> +extern struct backlight_device *backlight_device_get_by_type(enum backlight_type type);
> > >> +extern int backlight_device_set_brightness(struct backlight_device *bd, int brightness);
> > >>
> > >>  #define to_backlight_device(obj) container_of(obj, struct backlight_device, dev)
> > >>
> > >> --
> > >> 2.1.0
> > >
> >

Re: [PATCH 1/3] video / backlight: add two APIs for drivers to use

[Zhang Rui]

On Mon, 2015-01-05 at 15:20 +0900, Jingoo Han wrote:
> On Monday, January 05, 2015 3:01 PM, Zhang Rui wrote:
> > On Mon, 2015-01-05 at 13:46 +0800, Aaron Lu wrote:
> > > On 01/03/2015 09:04 AM, Jingoo Han wrote:
> > > > On Wednesday, December 31, 2014 12:50 PM, Aaron Lu wrote:
> > > >>
> > > >> It is useful to get the backlight device's pointer and use it to set
> > > >> backlight in some cases(the following patch will make use of it) so add
> > > >> the two APIs and export them.
> > > >>
> > > >> Signed-off-by: Aaron Lu <aaron.lu@intel.com>
> > > >
> > > > Acked-by: Jingoo Han <jg1.han@samsung.com>
> > >
> > So Jingoo and Lee, will you take the first two patches, or you'd like me
> > the take the whole patch set?
> 
> Hi Zhang Rui,
> 
> I would like you to take the whole patch set.
> This is because 3rd patch makes the build error
> without 1st & 2nd patches. Thank you.
> 
okay, thanks!

-rui

> Best regards,
> Jingoo Han
> 
> > 
> > thanks,
> > rui
> > > Thanks for the review!
> > >
> > > Regards,
> > > Aaron
> > >
> > > >
> > > > Best regards,
> > > > Jingoo Han
> > > >
> > > >> ---
> > > >>  drivers/video/backlight/backlight.c | 44 ++++++++++++++++++++++++-------------
> > > >>  include/linux/backlight.h           |  2 ++
> > > >>  2 files changed, 31 insertions(+), 15 deletions(-)
> > > >>
> > > >> diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
> > > >> index bddc8b17a4d8..bea749329236 100644
> > > >> --- a/drivers/video/backlight/backlight.c
> > > >> +++ b/drivers/video/backlight/backlight.c
> > > >> @@ -164,28 +164,19 @@ static ssize_t brightness_show(struct device *dev,
> > > >>  	return sprintf(buf, "%d\n", bd->props.brightness);
> > > >>  }
> > > >>
> > > >> -static ssize_t brightness_store(struct device *dev,
> > > >> -		struct device_attribute *attr, const char *buf, size_t count)
> > > >> +int backlight_device_set_brightness(struct backlight_device *bd, int brightness)
> > > >>  {
> > > >> -	int rc;
> > > >> -	struct backlight_device *bd = to_backlight_device(dev);
> > > >> -	unsigned long brightness;
> > > >> -
> > > >> -	rc = kstrtoul(buf, 0, &brightness);
> > > >> -	if (rc)
> > > >> -		return rc;
> > > >> -
> > > >> -	rc = -ENXIO;
> > > >> +	int rc = -ENXIO;
> > > >>
> > > >>  	mutex_lock(&bd->ops_lock);
> > > >>  	if (bd->ops) {
> > > >>  		if (brightness > bd->props.max_brightness)
> > > >>  			rc = -EINVAL;
> > > >>  		else {
> > > >> -			pr_debug("set brightness to %lu\n", brightness);
> > > >> +			pr_debug("set brightness to %u\n", brightness);
> > > >>  			bd->props.brightness = brightness;
> > > >>  			backlight_update_status(bd);
> > > >> -			rc = count;
> > > >> +			rc = 0;
> > > >>  		}
> > > >>  	}
> > > >>  	mutex_unlock(&bd->ops_lock);
> > > >> @@ -194,6 +185,23 @@ static ssize_t brightness_store(struct device *dev,
> > > >>
> > > >>  	return rc;
> > > >>  }
> > > >> +EXPORT_SYMBOL(backlight_device_set_brightness);
> > > >> +
> > > >> +static ssize_t brightness_store(struct device *dev,
> > > >> +		struct device_attribute *attr, const char *buf, size_t count)
> > > >> +{
> > > >> +	int rc;
> > > >> +	struct backlight_device *bd = to_backlight_device(dev);
> > > >> +	unsigned long brightness;
> > > >> +
> > > >> +	rc = kstrtoul(buf, 0, &brightness);
> > > >> +	if (rc)
> > > >> +		return rc;
> > > >> +
> > > >> +	rc = backlight_device_set_brightness(bd, brightness);
> > > >> +
> > > >> +	return rc ? rc : count;
> > > >> +}
> > > >>  static DEVICE_ATTR_RW(brightness);
> > > >>
> > > >>  static ssize_t type_show(struct device *dev, struct device_attribute *attr,
> > > >> @@ -380,7 +388,7 @@ struct backlight_device *backlight_device_register(const char *name,
> > > >>  }
> > > >>  EXPORT_SYMBOL(backlight_device_register);
> > > >>
> > > >> -bool backlight_device_registered(enum backlight_type type)
> > > >> +struct backlight_device *backlight_device_get_by_type(enum backlight_type type)
> > > >>  {
> > > >>  	bool found = false;
> > > >>  	struct backlight_device *bd;
> > > >> @@ -394,7 +402,13 @@ bool backlight_device_registered(enum backlight_type type)
> > > >>  	}
> > > >>  	mutex_unlock(&backlight_dev_list_mutex);
> > > >>
> > > >> -	return found;
> > > >> +	return found ? bd : NULL;
> > > >> +}
> > > >> +EXPORT_SYMBOL(backlight_device_get_by_type);
> > > >> +
> > > >> +bool backlight_device_registered(enum backlight_type type)
> > > >> +{
> > > >> +	return backlight_device_get_by_type(type) ? true : false;
> > > >>  }
> > > >>  EXPORT_SYMBOL(backlight_device_registered);
> > > >>
> > > >> diff --git a/include/linux/backlight.h b/include/linux/backlight.h
> > > >> index adb14a8616df..c59a020df3f8 100644
> > > >> --- a/include/linux/backlight.h
> > > >> +++ b/include/linux/backlight.h
> > > >> @@ -140,6 +140,8 @@ extern void backlight_force_update(struct backlight_device *bd,
> > > >>  extern bool backlight_device_registered(enum backlight_type type);
> > > >>  extern int backlight_register_notifier(struct notifier_block *nb);
> > > >>  extern int backlight_unregister_notifier(struct notifier_block *nb);
> > > >> +extern struct backlight_device *backlight_device_get_by_type(enum backlight_type type);
> > > >> +extern int backlight_device_set_brightness(struct backlight_device *bd, int brightness);
> > > >>
> > > >>  #define to_backlight_device(obj) container_of(obj, struct backlight_device, dev)
> > > >>
> > > >> --
> > > >> 2.1.0
> > > >
> > >
> 
> 

[PATCH v2 0/3] Support INT3406 Display thermal device

[Aaron Lu]

The display thermal device represents the LED/LCD display panel
that may or may not include touch support. The main function of
the display thermal device is to allow control of the display
brightness in order to address a thermal condition or to reduce
power consumed by display device.

Due to the way this thermal device changes brightness level is said
to be deprecated so we are using the raw interface to do the actual
backlight change. This requires the backlight core support so two
new APIs are added and exported in patch 1/3. With this, the previous
API backlight_device_registered can be removed and this is done in
patch 2/3. Patch 3/3 adds the new int3406 thermal driver.

The 1st version is here:
http://thread.gmane.org/gmane.linux.acpi.devel/72619

This whole series should go through the thermal tree if applied.

Aaron Lu (3):
  video / backlight: add two APIs for drivers to use
  video / backlight: remove the backlight_device_registered API
  Thermal: add INT3406 thermal driver

 drivers/acpi/acpi_video.c                         |  83 ++++----
 drivers/acpi/video_detect.c                       |   2 +-
 drivers/thermal/Kconfig                           |  28 +--
 drivers/thermal/int340x_thermal/Kconfig           |  42 ++++
 drivers/thermal/int340x_thermal/Makefile          |   1 +
 drivers/thermal/int340x_thermal/int3406_thermal.c | 236 ++++++++++++++++++++++
 drivers/video/backlight/backlight.c               |  39 ++--
 include/acpi/video.h                              |  20 ++
 include/linux/backlight.h                         |   3 +-
 9 files changed, 374 insertions(+), 80 deletions(-)
 create mode 100644 drivers/thermal/int340x_thermal/Kconfig
 create mode 100644 drivers/thermal/int340x_thermal/int3406_thermal.c

-- 
2.5.5

[PATCH 1/3] video / backlight: add two APIs for drivers to use

[Aaron Lu]

It is useful to get the backlight device's pointer and use it to set
backlight in some cases(the following patch will make use of it) so add
the two APIs and export them.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
---
 drivers/video/backlight/backlight.c | 43 +++++++++++++++++++++++++------------
 include/linux/backlight.h           |  2 ++
 2 files changed, 31 insertions(+), 14 deletions(-)

diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
index bddc8b17a4d8..18901b9b1eb4 100644
--- a/drivers/video/backlight/backlight.c
+++ b/drivers/video/backlight/backlight.c
@@ -164,18 +164,10 @@ static ssize_t brightness_show(struct device *dev,
 	return sprintf(buf, "%d\n", bd->props.brightness);
 }
 
-static ssize_t brightness_store(struct device *dev,
-		struct device_attribute *attr, const char *buf, size_t count)
+int backlight_device_set_brightness(struct backlight_device *bd,
+				    unsigned long brightness)
 {
-	int rc;
-	struct backlight_device *bd = to_backlight_device(dev);
-	unsigned long brightness;
-
-	rc = kstrtoul(buf, 0, &brightness);
-	if (rc)
-		return rc;
-
-	rc = -ENXIO;
+	int rc = -ENXIO;
 
 	mutex_lock(&bd->ops_lock);
 	if (bd->ops) {
@@ -185,7 +177,7 @@ static ssize_t brightness_store(struct device *dev,
 			pr_debug("set brightness to %lu\n", brightness);
 			bd->props.brightness = brightness;
 			backlight_update_status(bd);
-			rc = count;
+			rc = 0;
 		}
 	}
 	mutex_unlock(&bd->ops_lock);
@@ -194,6 +186,23 @@ static ssize_t brightness_store(struct device *dev,
 
 	return rc;
 }
+EXPORT_SYMBOL(backlight_device_set_brightness);
+
+static ssize_t brightness_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	int rc;
+	struct backlight_device *bd = to_backlight_device(dev);
+	unsigned long brightness;
+
+	rc = kstrtoul(buf, 0, &brightness);
+	if (rc)
+		return rc;
+
+	rc = backlight_device_set_brightness(bd, brightness);
+
+	return rc ? rc : count;
+}
 static DEVICE_ATTR_RW(brightness);
 
 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
@@ -380,7 +389,7 @@ struct backlight_device *backlight_device_register(const char *name,
 }
 EXPORT_SYMBOL(backlight_device_register);
 
-bool backlight_device_registered(enum backlight_type type)
+struct backlight_device *backlight_device_get_by_type(enum backlight_type type)
 {
 	bool found = false;
 	struct backlight_device *bd;
@@ -394,7 +403,13 @@ bool backlight_device_registered(enum backlight_type type)
 	}
 	mutex_unlock(&backlight_dev_list_mutex);
 
-	return found;
+	return found ? bd : NULL;
+}
+EXPORT_SYMBOL(backlight_device_get_by_type);
+
+bool backlight_device_registered(enum backlight_type type)
+{
+	return backlight_device_get_by_type(type) ? true : false;
 }
 EXPORT_SYMBOL(backlight_device_registered);
 
diff --git a/include/linux/backlight.h b/include/linux/backlight.h
index 1e7a69adbe6f..f46b88fa4a09 100644
--- a/include/linux/backlight.h
+++ b/include/linux/backlight.h
@@ -144,6 +144,8 @@ extern void backlight_force_update(struct backlight_device *bd,
 extern bool backlight_device_registered(enum backlight_type type);
 extern int backlight_register_notifier(struct notifier_block *nb);
 extern int backlight_unregister_notifier(struct notifier_block *nb);
+extern struct backlight_device *backlight_device_get_by_type(enum backlight_type type);
+extern int backlight_device_set_brightness(struct backlight_device *bd, unsigned long brightness);
 
 #define to_backlight_device(obj) container_of(obj, struct backlight_device, dev)
 
-- 
2.5.5

[PATCH 2/3] video / backlight: remove the backlight_device_registered API

[Aaron Lu]

Since we will need the backlight_device_get_by_type API, we can use it
instead of the backlight_device_registered API whenever necessary so
remove the backlight_device_registered API.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
---
 drivers/acpi/video_detect.c         | 2 +-
 drivers/video/backlight/backlight.c | 6 ------
 include/linux/backlight.h           | 1 -
 3 files changed, 1 insertion(+), 8 deletions(-)

diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c
index 1316ddd92fac..3d1327615f72 100644
--- a/drivers/acpi/video_detect.c
+++ b/drivers/acpi/video_detect.c
@@ -358,7 +358,7 @@ enum acpi_backlight_type acpi_video_get_backlight_type(void)
 	if (!(video_caps & ACPI_VIDEO_BACKLIGHT))
 		return acpi_backlight_vendor;
 
-	if (acpi_osi_is_win8() && backlight_device_registered(BACKLIGHT_RAW))
+	if (acpi_osi_is_win8() && backlight_device_get_by_type(BACKLIGHT_RAW))
 		return acpi_backlight_native;
 
 	return acpi_backlight_video;
diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
index 18901b9b1eb4..288318ad21dd 100644
--- a/drivers/video/backlight/backlight.c
+++ b/drivers/video/backlight/backlight.c
@@ -407,12 +407,6 @@ struct backlight_device *backlight_device_get_by_type(enum backlight_type type)
 }
 EXPORT_SYMBOL(backlight_device_get_by_type);
 
-bool backlight_device_registered(enum backlight_type type)
-{
-	return backlight_device_get_by_type(type) ? true : false;
-}
-EXPORT_SYMBOL(backlight_device_registered);
-
 /**
  * backlight_device_unregister - unregisters a backlight device object.
  * @bd: the backlight device object to be unregistered and freed.
diff --git a/include/linux/backlight.h b/include/linux/backlight.h
index f46b88fa4a09..5f2fd61ef4fb 100644
--- a/include/linux/backlight.h
+++ b/include/linux/backlight.h
@@ -141,7 +141,6 @@ extern void devm_backlight_device_unregister(struct device *dev,
 					struct backlight_device *bd);
 extern void backlight_force_update(struct backlight_device *bd,
 				   enum backlight_update_reason reason);
-extern bool backlight_device_registered(enum backlight_type type);
 extern int backlight_register_notifier(struct notifier_block *nb);
 extern int backlight_unregister_notifier(struct notifier_block *nb);
 extern struct backlight_device *backlight_device_get_by_type(enum backlight_type type);
-- 
2.5.5

[PATCH 3/3] Thermal: add INT3406 thermal driver

[Aaron Lu]

INT3406 ACPI device object resembles an ACPI video output device, but its
_BCM is said to be deprecated and should not be used. So we will make
use of the raw interface to do the actual cooling. Also, to re-use some
of the ACPI video module's code, function acpi_video_get_levels has been
exported.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
---
 drivers/acpi/acpi_video.c                         |  83 ++++----
 drivers/thermal/Kconfig                           |  28 +--
 drivers/thermal/int340x_thermal/Kconfig           |  42 ++++
 drivers/thermal/int340x_thermal/Makefile          |   1 +
 drivers/thermal/int340x_thermal/int3406_thermal.c | 236 ++++++++++++++++++++++
 include/acpi/video.h                              |  20 ++
 6 files changed, 347 insertions(+), 63 deletions(-)
 create mode 100644 drivers/thermal/int340x_thermal/Kconfig
 create mode 100644 drivers/thermal/int340x_thermal/int3406_thermal.c

diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c
index 4361bc98ef4c..3d5b8a099351 100644
--- a/drivers/acpi/acpi_video.c
+++ b/drivers/acpi/acpi_video.c
@@ -191,19 +191,6 @@ struct acpi_video_device_cap {
 	u8 _DDC:1;		/* Return the EDID for this device */
 };
 
-struct acpi_video_brightness_flags {
-	u8 _BCL_no_ac_battery_levels:1;	/* no AC/Battery levels in _BCL */
-	u8 _BCL_reversed:1;		/* _BCL package is in a reversed order */
-	u8 _BQC_use_index:1;		/* _BQC returns an index value */
-};
-
-struct acpi_video_device_brightness {
-	int curr;
-	int count;
-	int *levels;
-	struct acpi_video_brightness_flags flags;
-};
-
 struct acpi_video_device {
 	unsigned long device_id;
 	struct acpi_video_device_flags flags;
@@ -325,7 +312,7 @@ static const struct thermal_cooling_device_ops video_cooling_ops = {
  */
 
 static int
-acpi_video_device_lcd_query_levels(struct acpi_video_device *device,
+acpi_video_device_lcd_query_levels(acpi_handle handle,
 				   union acpi_object **levels)
 {
 	int status;
@@ -335,7 +322,7 @@ acpi_video_device_lcd_query_levels(struct acpi_video_device *device,
 
 	*levels = NULL;
 
-	status = acpi_evaluate_object(device->dev->handle, "_BCL", NULL, &buffer);
+	status = acpi_evaluate_object(handle, "_BCL", NULL, &buffer);
 	if (!ACPI_SUCCESS(status))
 		return status;
 	obj = (union acpi_object *)buffer.pointer;
@@ -766,36 +753,28 @@ static int acpi_video_bqc_quirk(struct acpi_video_device *device,
 	return 0;
 }
 
-
-/*
- *  Arg:
- *	device	: video output device (LCD, CRT, ..)
- *
- *  Return Value:
- *	Maximum brightness level
- *
- *  Allocate and initialize device->brightness.
- */
-
-static int
-acpi_video_init_brightness(struct acpi_video_device *device)
+int acpi_video_get_levels(struct acpi_device *device,
+			  struct acpi_video_device_brightness **dev_br)
 {
 	union acpi_object *obj = NULL;
 	int i, max_level = 0, count = 0, level_ac_battery = 0;
-	unsigned long long level, level_old;
 	union acpi_object *o;
 	struct acpi_video_device_brightness *br = NULL;
-	int result = -EINVAL;
+	int result = 0;
 	u32 value;
 
-	if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device, &obj))) {
+	if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device->handle,
+								&obj))) {
 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
 						"LCD brightness level\n"));
+		result = -ENODEV;
 		goto out;
 	}
 
-	if (obj->package.count < 2)
+	if (obj->package.count < 2) {
+		result = -EINVAL;
 		goto out;
+	}
 
 	br = kzalloc(sizeof(*br), GFP_KERNEL);
 	if (!br) {
@@ -861,6 +840,38 @@ acpi_video_init_brightness(struct acpi_video_device *device)
 			    "Found unordered _BCL package"));
 
 	br->count = count;
+	*dev_br = br;
+
+out:
+	kfree(obj);
+	return result;
+out_free:
+	kfree(br);
+	goto out;
+}
+EXPORT_SYMBOL(acpi_video_get_levels);
+
+/*
+ *  Arg:
+ *	device	: video output device (LCD, CRT, ..)
+ *
+ *  Return Value:
+ *	Maximum brightness level
+ *
+ *  Allocate and initialize device->brightness.
+ */
+
+static int
+acpi_video_init_brightness(struct acpi_video_device *device)
+{
+	int i, max_level = 0;
+	unsigned long long level, level_old;
+	struct acpi_video_device_brightness *br = NULL;
+	int result = -EINVAL;
+
+	result = acpi_video_get_levels(device->dev, &br);
+	if (result)
+		return result;
 	device->brightness = br;
 
 	/* _BQC uses INDEX while _BCL uses VALUE in some laptops */
@@ -903,17 +914,13 @@ set_level:
 		goto out_free_levels;
 
 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-			  "found %d brightness levels\n", count - 2));
-	kfree(obj);
-	return result;
+			  "found %d brightness levels\n", br->count - 2));
+	return 0;
 
 out_free_levels:
 	kfree(br->levels);
-out_free:
 	kfree(br);
-out:
 	device->brightness = NULL;
-	kfree(obj);
 	return result;
 }
 
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index c37eedc35a24..cb1ba70ceaa7 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -338,31 +338,9 @@ config INTEL_QUARK_DTS_THERMAL
 	  hot & critical. The critical trip point default value is set by
 	  underlying BIOS/Firmware.
 
-config INT340X_THERMAL
-	tristate "ACPI INT340X thermal drivers"
-	depends on X86 && ACPI
-	select THERMAL_GOV_USER_SPACE
-	select ACPI_THERMAL_REL
-	select ACPI_FAN
-	select INTEL_SOC_DTS_IOSF_CORE
-	select THERMAL_WRITABLE_TRIPS
-	help
-	  Newer laptops and tablets that use ACPI may have thermal sensors and
-	  other devices with thermal control capabilities outside the core
-	  CPU/SOC, for thermal safety reasons.
-	  They are exposed for the OS to use via the INT3400 ACPI device object
-	  as the master, and INT3401~INT340B ACPI device objects as the slaves.
-	  Enable this to expose the temperature information and cooling ability
-	  from these objects to userspace via the normal thermal framework.
-	  This means that a wide range of applications and GUI widgets can show
-	  the information to the user or use this information for making
-	  decisions. For example, the Intel Thermal Daemon can use this
-	  information to allow the user to select his laptop to run without
-	  turning on the fans.
-
-config ACPI_THERMAL_REL
-	tristate
-	depends on ACPI
+menu "ACPI INT340X thermal drivers"
+source drivers/thermal/int340x_thermal/Kconfig
+endmenu
 
 config INTEL_PCH_THERMAL
 	tristate "Intel PCH Thermal Reporting Driver"
diff --git a/drivers/thermal/int340x_thermal/Kconfig b/drivers/thermal/int340x_thermal/Kconfig
new file mode 100644
index 000000000000..0582bd12a239
--- /dev/null
+++ b/drivers/thermal/int340x_thermal/Kconfig
@@ -0,0 +1,42 @@
+#
+# ACPI INT340x thermal drivers configuration
+#
+
+config INT340X_THERMAL
+	tristate "ACPI INT340X thermal drivers"
+	depends on X86 && ACPI
+	select THERMAL_GOV_USER_SPACE
+	select ACPI_THERMAL_REL
+	select ACPI_FAN
+	select INTEL_SOC_DTS_IOSF_CORE
+	help
+	  Newer laptops and tablets that use ACPI may have thermal sensors and
+	  other devices with thermal control capabilities outside the core
+	  CPU/SOC, for thermal safety reasons.
+	  They are exposed for the OS to use via the INT3400 ACPI device object
+	  as the master, and INT3401~INT340B ACPI device objects as the slaves.
+	  Enable this to expose the temperature information and cooling ability
+	  from these objects to userspace via the normal thermal framework.
+	  This means that a wide range of applications and GUI widgets can show
+	  the information to the user or use this information for making
+	  decisions. For example, the Intel Thermal Daemon can use this
+	  information to allow the user to select his laptop to run without
+	  turning on the fans.
+
+config ACPI_THERMAL_REL
+	tristate
+	depends on ACPI
+
+if INT340X_THERMAL
+
+config INT3406_THERMAL
+	tristate "ACPI INT3406 display thermal driver"
+	depends on ACPI_VIDEO
+	help
+	  The display thermal device represents the LED/LCD display panel
+	  that may or may not include touch support. The main function of
+	  the display thermal device is to allow control of the display
+	  brightness in order to address a thermal condition or to reduce
+	  power consumed by display device.
+
+endif
diff --git a/drivers/thermal/int340x_thermal/Makefile b/drivers/thermal/int340x_thermal/Makefile
index ba77a34f659f..df0df055e7ff 100644
--- a/drivers/thermal/int340x_thermal/Makefile
+++ b/drivers/thermal/int340x_thermal/Makefile
@@ -3,4 +3,5 @@ obj-$(CONFIG_INT340X_THERMAL)	+= int340x_thermal_zone.o
 obj-$(CONFIG_INT340X_THERMAL)	+= int3402_thermal.o
 obj-$(CONFIG_INT340X_THERMAL)	+= int3403_thermal.o
 obj-$(CONFIG_INT340X_THERMAL)	+= processor_thermal_device.o
+obj-$(CONFIG_INT3406_THERMAL)	+= int3406_thermal.o
 obj-$(CONFIG_ACPI_THERMAL_REL)	+= acpi_thermal_rel.o
diff --git a/drivers/thermal/int340x_thermal/int3406_thermal.c b/drivers/thermal/int340x_thermal/int3406_thermal.c
new file mode 100644
index 000000000000..1c9b7590f098
--- /dev/null
+++ b/drivers/thermal/int340x_thermal/int3406_thermal.c
@@ -0,0 +1,236 @@
+/*
+ * INT3406 thermal driver for display participant device
+ *
+ * Copyright (C) 2014, Intel Corporation
+ * Authors: Aaron Lu <aaron.lu@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/acpi.h>
+#include <linux/backlight.h>
+#include <linux/thermal.h>
+#include <acpi/video.h>
+
+#define INT3406_BRIGHTNESS_LIMITS_CHANGED	0x80
+
+struct int3406_thermal_data {
+	int upper_limit;
+	int upper_limit_index;
+	int lower_limit;
+	int lower_limit_index;
+	acpi_handle handle;
+	struct acpi_video_device_brightness *br;
+	struct backlight_device *raw_bd;
+	struct thermal_cooling_device *cooling_dev;
+};
+
+static int int3406_thermal_to_raw(int level, struct int3406_thermal_data *d)
+{
+	int max_level = d->br->levels[d->br->count - 1];
+	int raw_max = d->raw_bd->props.max_brightness;
+
+	return level * raw_max / max_level;
+}
+
+static int int3406_thermal_to_acpi(int level, struct int3406_thermal_data *d)
+{
+	int raw_max = d->raw_bd->props.max_brightness;
+	int max_level = d->br->levels[d->br->count - 1];
+
+	return level * max_level / raw_max;
+}
+
+static int
+int3406_thermal_get_max_state(struct thermal_cooling_device *cooling_dev,
+			      unsigned long *state)
+{
+	struct int3406_thermal_data *d = cooling_dev->devdata;
+	int index = d->lower_limit_index ? d->lower_limit_index : 2;
+
+	*state = d->br->count - 1 - index;
+	return 0;
+}
+
+static int
+int3406_thermal_set_cur_state(struct thermal_cooling_device *cooling_dev,
+			      unsigned long state)
+{
+	struct int3406_thermal_data *d = cooling_dev->devdata;
+	int level, raw_level;
+
+	if (state > d->br->count - 3)
+		return -EINVAL;
+
+	state = d->br->count - 1 - state;
+	level = d->br->levels[state];
+
+	if ((d->upper_limit && level > d->upper_limit) ||
+	    (d->lower_limit && level < d->lower_limit))
+		return -EINVAL;
+
+	raw_level = int3406_thermal_to_raw(level, d);
+	return backlight_device_set_brightness(d->raw_bd, raw_level);
+}
+
+static int
+int3406_thermal_get_cur_state(struct thermal_cooling_device *cooling_dev,
+			      unsigned long *state)
+{
+	struct int3406_thermal_data *d = cooling_dev->devdata;
+	int raw_level, level, i;
+	int *levels = d->br->levels;
+
+	raw_level = d->raw_bd->props.brightness;
+	level = int3406_thermal_to_acpi(raw_level, d);
+
+	/*
+	 * There is no 1:1 mapping between the firmware interface level with the
+	 * raw interface level, we will have to find one that is close enough.
+	 */
+	for (i = 2; i < d->br->count; i++) {
+		if (level < levels[i]) {
+			if (i == 2)
+				break;
+			if ((level - levels[i - 1]) < (levels[i] - level))
+				i--;
+			break;
+		}
+	}
+
+	*state = d->br->count - 1 - i;
+	return 0;
+}
+
+static const struct thermal_cooling_device_ops video_cooling_ops = {
+	.get_max_state = int3406_thermal_get_max_state,
+	.get_cur_state = int3406_thermal_get_cur_state,
+	.set_cur_state = int3406_thermal_set_cur_state,
+};
+
+static int int3406_thermal_get_index(int *array, int nr, int value)
+{
+	int i;
+
+	for (i = 0; i < nr; i++) {
+		if (array[i] == value)
+			break;
+	}
+	return i == nr ? -ENOENT : i;
+}
+
+static void int3406_thermal_get_limit(struct int3406_thermal_data *d)
+{
+	acpi_status status;
+	unsigned long long lower_limit, upper_limit;
+	int index;
+
+	status = acpi_evaluate_integer(d->handle, "DDDL", NULL, &lower_limit);
+	if (ACPI_SUCCESS(status)) {
+		index = int3406_thermal_get_index(d->br->levels, d->br->count,
+						  lower_limit);
+		if (index > 0) {
+			d->lower_limit = (int)lower_limit;
+			d->lower_limit_index = index;
+		}
+	}
+
+	status = acpi_evaluate_integer(d->handle, "DDPC", NULL, &upper_limit);
+	if (ACPI_SUCCESS(status)) {
+		index = int3406_thermal_get_index(d->br->levels, d->br->count,
+						  upper_limit);
+		if (index > 0) {
+			d->upper_limit = (int)upper_limit;
+			d->upper_limit_index = index;
+		}
+	}
+}
+
+static void int3406_notify(acpi_handle handle, u32 event, void *data)
+{
+	if (event == INT3406_BRIGHTNESS_LIMITS_CHANGED)
+		int3406_thermal_get_limit(data);
+}
+
+static int int3406_thermal_probe(struct platform_device *pdev)
+{
+	struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
+	struct int3406_thermal_data *d;
+	struct backlight_device *bd;
+	int ret;
+
+	if (!ACPI_HANDLE(&pdev->dev))
+		return -ENODEV;
+
+	d = devm_kzalloc(&pdev->dev, sizeof(*d), GFP_KERNEL);
+	if (!d)
+		return -ENOMEM;
+	d->handle = ACPI_HANDLE(&pdev->dev);
+
+	bd = backlight_device_get_by_type(BACKLIGHT_RAW);
+	if (!bd)
+		return -ENODEV;
+	d->raw_bd = bd;
+
+	ret = acpi_video_get_levels(ACPI_COMPANION(&pdev->dev), &d->br);
+	if (ret)
+		return ret;
+
+	int3406_thermal_get_limit(d);
+
+	d->cooling_dev = thermal_cooling_device_register(acpi_device_bid(adev),
+							 d, &video_cooling_ops);
+	if (IS_ERR(d->cooling_dev))
+		goto err;
+
+	ret = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
+					  int3406_notify, d);
+	if (ret)
+		goto err_cdev;
+
+	platform_set_drvdata(pdev, d);
+
+	return 0;
+
+err_cdev:
+	thermal_cooling_device_unregister(d->cooling_dev);
+err:
+	kfree(d->br);
+	return -ENODEV;
+}
+
+static int int3406_thermal_remove(struct platform_device *pdev)
+{
+	struct int3406_thermal_data *d = platform_get_drvdata(pdev);
+
+	thermal_cooling_device_unregister(d->cooling_dev);
+	kfree(d->br);
+	return 0;
+}
+
+static const struct acpi_device_id int3406_thermal_match[] = {
+	{"INT3406", 0},
+	{}
+};
+
+MODULE_DEVICE_TABLE(acpi, int3406_thermal_match);
+
+static struct platform_driver int3406_thermal_driver = {
+	.probe = int3406_thermal_probe,
+	.remove = int3406_thermal_remove,
+	.driver = {
+		   .name = "int3406 thermal",
+		   .owner = THIS_MODULE,
+		   .acpi_match_table = int3406_thermal_match,
+		   },
+};
+
+module_platform_driver(int3406_thermal_driver);
+
+MODULE_DESCRIPTION("INT3406 Thermal driver");
+MODULE_LICENSE("GPL");
diff --git a/include/acpi/video.h b/include/acpi/video.h
index 5ca2f2c16458..a4b96c971564 100644
--- a/include/acpi/video.h
+++ b/include/acpi/video.h
@@ -4,6 +4,19 @@
 #include <linux/errno.h> /* for ENODEV */
 #include <linux/types.h> /* for bool */
 
+struct acpi_video_brightness_flags {
+	u8 _BCL_no_ac_battery_levels:1;	/* no AC/Battery levels in _BCL */
+	u8 _BCL_reversed:1;		/* _BCL package is in a reversed order */
+	u8 _BQC_use_index:1;		/* _BQC returns an index value */
+};
+
+struct acpi_video_device_brightness {
+	int curr;
+	int count;
+	int *levels;
+	struct acpi_video_brightness_flags flags;
+};
+
 struct acpi_device;
 
 #define ACPI_VIDEO_CLASS	"video"
@@ -37,6 +50,8 @@ extern void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type);
  * may change over time and should not be cached.
  */
 extern bool acpi_video_handles_brightness_key_presses(void);
+extern int acpi_video_get_levels(struct acpi_device *device,
+				 struct acpi_video_device_brightness **dev_br);
 #else
 static inline int acpi_video_register(void) { return 0; }
 static inline void acpi_video_unregister(void) { return; }
@@ -56,6 +71,11 @@ static inline bool acpi_video_handles_brightness_key_presses(void)
 {
 	return false;
 }
+static int acpi_video_get_levels(struct acpi_device *device,
+			struct acpi_video_device_brightness **dev_br)
+{
+	return -ENODEV;
+}
 #endif
 
 #endif
-- 
2.5.5

Re: [PATCH v2 0/3] Support INT3406 Display thermal device

[Rafael J. Wysocki]

On Wednesday, April 13, 2016 03:32:48 PM Aaron Lu wrote:
> The display thermal device represents the LED/LCD display panel
> that may or may not include touch support. The main function of
> the display thermal device is to allow control of the display
> brightness in order to address a thermal condition or to reduce
> power consumed by display device.
> 
> Due to the way this thermal device changes brightness level is said
> to be deprecated so we are using the raw interface to do the actual
> backlight change. This requires the backlight core support so two
> new APIs are added and exported in patch 1/3. With this, the previous
> API backlight_device_registered can be removed and this is done in
> patch 2/3. Patch 3/3 adds the new int3406 thermal driver.
> 
> The 1st version is here:
> http://thread.gmane.org/gmane.linux.acpi.devel/72619
> 
> This whole series should go through the thermal tree if applied.
> 
> Aaron Lu (3):
>   video / backlight: add two APIs for drivers to use
>   video / backlight: remove the backlight_device_registered API
>   Thermal: add INT3406 thermal driver

So I have nothing against [1-2/3], but the [3/3] tries to do too many things
in one go.  It should be at least two separate patches to my eyes, one making
changes to the ACPI video driver and the other adding the INT3406 one.

Thanks,
Rafael

Re: [PATCH v2 0/3] Support INT3406 Display thermal device

[Aaron Lu]

On 04/26/2016 08:58 AM, Rafael J. Wysocki wrote:
> On Wednesday, April 13, 2016 03:32:48 PM Aaron Lu wrote:
>> The display thermal device represents the LED/LCD display panel
>> that may or may not include touch support. The main function of
>> the display thermal device is to allow control of the display
>> brightness in order to address a thermal condition or to reduce
>> power consumed by display device.
>>
>> Due to the way this thermal device changes brightness level is said
>> to be deprecated so we are using the raw interface to do the actual
>> backlight change. This requires the backlight core support so two
>> new APIs are added and exported in patch 1/3. With this, the previous
>> API backlight_device_registered can be removed and this is done in
>> patch 2/3. Patch 3/3 adds the new int3406 thermal driver.
>>
>> The 1st version is here:
>> http://thread.gmane.org/gmane.linux.acpi.devel/72619
>>
>> This whole series should go through the thermal tree if applied.
>>
>> Aaron Lu (3):
>>   video / backlight: add two APIs for drivers to use
>>   video / backlight: remove the backlight_device_registered API
>>   Thermal: add INT3406 thermal driver
> 
> So I have nothing against [1-2/3], but the [3/3] tries to do too many things
> in one go.  It should be at least two separate patches to my eyes, one making
> changes to the ACPI video driver and the other adding the INT3406 one.

Thanks for the review, will split the last patch and re-send.

Regards,
Aaron