[03/17] Input: sun4i-ts: Add thermal zone sensor support
diff mbox

Message ID 1420511727-8242-4-git-send-email-wens@csie.org
State New, archived
Headers show

Commit Message

Chen-Yu Tsai (Moxa) Jan. 6, 2015, 2:35 a.m. UTC
The touchscreen controller has a temperature sensor embedded in the SoC,
which already has hwmon support in the driver.

Add DT thermal zone support so we can use it with cpufreq for thermal
throttling.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
---
 .../bindings/input/touchscreen/sun4i.txt           |  1 +
 drivers/input/touchscreen/sun4i-ts.c               | 27 ++++++++++++++++++++++
 2 files changed, 28 insertions(+)

Comments

Eduardo Valentin Jan. 6, 2015, 3:24 p.m. UTC | #1
Hello Chen-Yu,


On Tue, Jan 06, 2015 at 10:35:13AM +0800, Chen-Yu Tsai wrote:
> The touchscreen controller has a temperature sensor embedded in the SoC,
> which already has hwmon support in the driver.
> 
> Add DT thermal zone support so we can use it with cpufreq for thermal
> throttling.
> 
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
> ---
>  .../bindings/input/touchscreen/sun4i.txt           |  1 +
>  drivers/input/touchscreen/sun4i-ts.c               | 27 ++++++++++++++++++++++
>  2 files changed, 28 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
> index aef57791f40b..7f1110adbd24 100644
> --- a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
> +++ b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
> @@ -5,6 +5,7 @@ Required properties:
>   - compatible: "allwinner,sun4i-a10-ts"
>   - reg: mmio address range of the chip
>   - interrupts: interrupt to which the chip is connected
> + - #thermal-sensor-cells: shall be 0
>  

You may want to update your Example section too, below.
Example:

	rtp: rtp@01c25000 {
		compatible = "allwinner,sun4i-a10-ts";
		reg = <0x01c25000 0x100>;
		interrupts = <29>;
		allwinner,ts-attached;
		#thermal-sensor-cells = <0>;
	};


>  Optional properties:
>   - allwinner,ts-attached: boolean indicating that an actual touchscreen is
> diff --git a/drivers/input/touchscreen/sun4i-ts.c b/drivers/input/touchscreen/sun4i-ts.c
> index 28a06749ae42..b6e9043446d6 100644
> --- a/drivers/input/touchscreen/sun4i-ts.c
> +++ b/drivers/input/touchscreen/sun4i-ts.c
> @@ -34,6 +34,7 @@
>  
>  #include <linux/err.h>
>  #include <linux/hwmon.h>
> +#include <linux/thermal.h>
>  #include <linux/init.h>
>  #include <linux/input.h>
>  #include <linux/interrupt.h>
> @@ -107,6 +108,7 @@
>  struct sun4i_ts_data {
>  	struct device *dev;
>  	struct input_dev *input;
> +	struct thermal_zone_device *tz;
>  	void __iomem *base;
>  	unsigned int irq;
>  	bool ignore_fifo_data;
> @@ -180,6 +182,23 @@ static void sun4i_ts_close(struct input_dev *dev)
>  	writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
>  }
>  
> +static int get_temp(void *data, long *temp)
> +{
> +	struct sun4i_ts_data *ts = data;
> +
> +	/* No temp_data until the first irq */
> +	if (ts->temp_data == -1)
> +		return -EAGAIN;
> +
> +	*temp = (ts->temp_data - 1447) * 100;
> +

Care to explain the formula in a simple comment?

> +	return 0;
> +}
> +
> +static struct thermal_zone_of_device_ops sun4i_ts_tz_ops = {
> +	.get_temp = get_temp,
> +};
> +
>  static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
>  			 char *buf)
>  {
> @@ -288,6 +307,11 @@ static int sun4i_ts_probe(struct platform_device *pdev)
>  	if (IS_ERR(hwmon))
>  		return PTR_ERR(hwmon);
>  
> +	ts->tz = thermal_zone_of_sensor_register(ts->dev, 0, ts,
> +						 &sun4i_ts_tz_ops);
> +	if (IS_ERR(ts->tz))
> +		ts->tz = NULL;
> +
>  	writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
>  
>  	if (ts_attached) {

here.. if input_register_device fails, you will keep an orphan thermal zone
registered in your system:

		error = input_register_device(ts->input);
		if (error) {
			writel(0, ts->base + TP_INT_FIFOC);
			return error;
		}
		...


> @@ -310,6 +334,9 @@ static int sun4i_ts_remove(struct platform_device *pdev)
>  	if (ts->input)
>  		input_unregister_device(ts->input);
>  
> +	if (ts->tz)
> +		thermal_zone_of_sensor_unregister(ts->dev, ts->tz);
> +
>  	/* Deactivate all IRQs */
>  	writel(0, ts->base + TP_INT_FIFOC);
>  
> -- 
> 2.1.4
>
Chen-Yu Tsai (Moxa) Jan. 7, 2015, 4:24 p.m. UTC | #2
Hi,

On Tue, Jan 6, 2015 at 11:24 PM, Eduardo Valentin <edubezval@gmail.com> wrote:
> Hello Chen-Yu,
>
>
> On Tue, Jan 06, 2015 at 10:35:13AM +0800, Chen-Yu Tsai wrote:
>> The touchscreen controller has a temperature sensor embedded in the SoC,
>> which already has hwmon support in the driver.
>>
>> Add DT thermal zone support so we can use it with cpufreq for thermal
>> throttling.
>>
>> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
>> ---
>>  .../bindings/input/touchscreen/sun4i.txt           |  1 +
>>  drivers/input/touchscreen/sun4i-ts.c               | 27 ++++++++++++++++++++++
>>  2 files changed, 28 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
>> index aef57791f40b..7f1110adbd24 100644
>> --- a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
>> +++ b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
>> @@ -5,6 +5,7 @@ Required properties:
>>   - compatible: "allwinner,sun4i-a10-ts"
>>   - reg: mmio address range of the chip
>>   - interrupts: interrupt to which the chip is connected
>> + - #thermal-sensor-cells: shall be 0
>>
>
> You may want to update your Example section too, below.
> Example:
>
>         rtp: rtp@01c25000 {
>                 compatible = "allwinner,sun4i-a10-ts";
>                 reg = <0x01c25000 0x100>;
>                 interrupts = <29>;
>                 allwinner,ts-attached;
>                 #thermal-sensor-cells = <0>;
>         };

Ok.

>
>
>>  Optional properties:
>>   - allwinner,ts-attached: boolean indicating that an actual touchscreen is
>> diff --git a/drivers/input/touchscreen/sun4i-ts.c b/drivers/input/touchscreen/sun4i-ts.c
>> index 28a06749ae42..b6e9043446d6 100644
>> --- a/drivers/input/touchscreen/sun4i-ts.c
>> +++ b/drivers/input/touchscreen/sun4i-ts.c
>> @@ -34,6 +34,7 @@
>>
>>  #include <linux/err.h>
>>  #include <linux/hwmon.h>
>> +#include <linux/thermal.h>
>>  #include <linux/init.h>
>>  #include <linux/input.h>
>>  #include <linux/interrupt.h>
>> @@ -107,6 +108,7 @@
>>  struct sun4i_ts_data {
>>       struct device *dev;
>>       struct input_dev *input;
>> +     struct thermal_zone_device *tz;
>>       void __iomem *base;
>>       unsigned int irq;
>>       bool ignore_fifo_data;
>> @@ -180,6 +182,23 @@ static void sun4i_ts_close(struct input_dev *dev)
>>       writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
>>  }
>>
>> +static int get_temp(void *data, long *temp)
>> +{
>> +     struct sun4i_ts_data *ts = data;
>> +
>> +     /* No temp_data until the first irq */
>> +     if (ts->temp_data == -1)
>> +             return -EAGAIN;
>> +
>> +     *temp = (ts->temp_data - 1447) * 100;
>> +
>
> Care to explain the formula in a simple comment?

This was just copied from the hwmon section. AFAIK there is no documentation
for the formula. It was probably copied from Allwinner's SDK code.

Hans? Do you remember where you got this?

>> +     return 0;
>> +}
>> +
>> +static struct thermal_zone_of_device_ops sun4i_ts_tz_ops = {
>> +     .get_temp = get_temp,
>> +};
>> +
>>  static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
>>                        char *buf)
>>  {
>> @@ -288,6 +307,11 @@ static int sun4i_ts_probe(struct platform_device *pdev)
>>       if (IS_ERR(hwmon))
>>               return PTR_ERR(hwmon);
>>
>> +     ts->tz = thermal_zone_of_sensor_register(ts->dev, 0, ts,
>> +                                              &sun4i_ts_tz_ops);
>> +     if (IS_ERR(ts->tz))
>> +             ts->tz = NULL;
>> +
>>       writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
>>
>>       if (ts_attached) {
>
> here.. if input_register_device fails, you will keep an orphan thermal zone
> registered in your system:
>
>                 error = input_register_device(ts->input);
>                 if (error) {
>                         writel(0, ts->base + TP_INT_FIFOC);

Will add an unregister call here.


Thanks for the review.

ChenYu

>                         return error;
>                 }
>                 ...
>
>
>> @@ -310,6 +334,9 @@ static int sun4i_ts_remove(struct platform_device *pdev)
>>       if (ts->input)
>>               input_unregister_device(ts->input);
>>
>> +     if (ts->tz)
>> +             thermal_zone_of_sensor_unregister(ts->dev, ts->tz);
>> +
>>       /* Deactivate all IRQs */
>>       writel(0, ts->base + TP_INT_FIFOC);
>>
>> --
>> 2.1.4
>>
Chen-Yu Tsai (Moxa) Jan. 8, 2015, 1:33 p.m. UTC | #3
On Thu, Jan 8, 2015 at 12:24 AM, Chen-Yu Tsai <wens@csie.org> wrote:
> Hi,
>
> On Tue, Jan 6, 2015 at 11:24 PM, Eduardo Valentin <edubezval@gmail.com> wrote:
>> Hello Chen-Yu,
>>
>>
>> On Tue, Jan 06, 2015 at 10:35:13AM +0800, Chen-Yu Tsai wrote:
>>> The touchscreen controller has a temperature sensor embedded in the SoC,
>>> which already has hwmon support in the driver.
>>>
>>> Add DT thermal zone support so we can use it with cpufreq for thermal
>>> throttling.
>>>
>>> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
>>> ---
>>>  .../bindings/input/touchscreen/sun4i.txt           |  1 +
>>>  drivers/input/touchscreen/sun4i-ts.c               | 27 ++++++++++++++++++++++
>>>  2 files changed, 28 insertions(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
>>> index aef57791f40b..7f1110adbd24 100644
>>> --- a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
>>> +++ b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
>>> @@ -5,6 +5,7 @@ Required properties:
>>>   - compatible: "allwinner,sun4i-a10-ts"
>>>   - reg: mmio address range of the chip
>>>   - interrupts: interrupt to which the chip is connected
>>> + - #thermal-sensor-cells: shall be 0
>>>
>>
>> You may want to update your Example section too, below.
>> Example:
>>
>>         rtp: rtp@01c25000 {
>>                 compatible = "allwinner,sun4i-a10-ts";
>>                 reg = <0x01c25000 0x100>;
>>                 interrupts = <29>;
>>                 allwinner,ts-attached;
>>                 #thermal-sensor-cells = <0>;
>>         };
>
> Ok.
>
>>
>>
>>>  Optional properties:
>>>   - allwinner,ts-attached: boolean indicating that an actual touchscreen is
>>> diff --git a/drivers/input/touchscreen/sun4i-ts.c b/drivers/input/touchscreen/sun4i-ts.c
>>> index 28a06749ae42..b6e9043446d6 100644
>>> --- a/drivers/input/touchscreen/sun4i-ts.c
>>> +++ b/drivers/input/touchscreen/sun4i-ts.c
>>> @@ -34,6 +34,7 @@
>>>
>>>  #include <linux/err.h>
>>>  #include <linux/hwmon.h>
>>> +#include <linux/thermal.h>
>>>  #include <linux/init.h>
>>>  #include <linux/input.h>
>>>  #include <linux/interrupt.h>
>>> @@ -107,6 +108,7 @@
>>>  struct sun4i_ts_data {
>>>       struct device *dev;
>>>       struct input_dev *input;
>>> +     struct thermal_zone_device *tz;
>>>       void __iomem *base;
>>>       unsigned int irq;
>>>       bool ignore_fifo_data;
>>> @@ -180,6 +182,23 @@ static void sun4i_ts_close(struct input_dev *dev)
>>>       writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
>>>  }
>>>
>>> +static int get_temp(void *data, long *temp)
>>> +{
>>> +     struct sun4i_ts_data *ts = data;
>>> +
>>> +     /* No temp_data until the first irq */
>>> +     if (ts->temp_data == -1)
>>> +             return -EAGAIN;
>>> +
>>> +     *temp = (ts->temp_data - 1447) * 100;
>>> +
>>
>> Care to explain the formula in a simple comment?
>
> This was just copied from the hwmon section. AFAIK there is no documentation
> for the formula. It was probably copied from Allwinner's SDK code.
>
> Hans? Do you remember where you got this?

So this is from the AXP209 datasheet. The Allwinner SoC datasheets don't
mention the formula to calculate the temperature. But since Allwinner
and X-powers are affiliated, it's possible they use the same formula.

http://comments.gmane.org/gmane.comp.hardware.netbook.arm.sunxi/3838

>>> +     return 0;
>>> +}
>>> +
>>> +static struct thermal_zone_of_device_ops sun4i_ts_tz_ops = {
>>> +     .get_temp = get_temp,
>>> +};
>>> +
>>>  static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
>>>                        char *buf)
>>>  {
>>> @@ -288,6 +307,11 @@ static int sun4i_ts_probe(struct platform_device *pdev)
>>>       if (IS_ERR(hwmon))
>>>               return PTR_ERR(hwmon);
>>>
>>> +     ts->tz = thermal_zone_of_sensor_register(ts->dev, 0, ts,
>>> +                                              &sun4i_ts_tz_ops);
>>> +     if (IS_ERR(ts->tz))
>>> +             ts->tz = NULL;
>>> +
>>>       writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
>>>
>>>       if (ts_attached) {
>>
>> here.. if input_register_device fails, you will keep an orphan thermal zone
>> registered in your system:
>>
>>                 error = input_register_device(ts->input);
>>                 if (error) {
>>                         writel(0, ts->base + TP_INT_FIFOC);
>
> Will add an unregister call here.
>
>
> Thanks for the review.
>
> ChenYu
>
>>                         return error;
>>                 }
>>                 ...
>>
>>
>>> @@ -310,6 +334,9 @@ static int sun4i_ts_remove(struct platform_device *pdev)
>>>       if (ts->input)
>>>               input_unregister_device(ts->input);
>>>
>>> +     if (ts->tz)
>>> +             thermal_zone_of_sensor_unregister(ts->dev, ts->tz);
>>> +
>>>       /* Deactivate all IRQs */
>>>       writel(0, ts->base + TP_INT_FIFOC);
>>>
>>> --
>>> 2.1.4
>>>
Eduardo Valentin Jan. 9, 2015, 6:07 p.m. UTC | #4
On Thu, Jan 08, 2015 at 09:33:54PM +0800, Chen-Yu Tsai wrote:
> On Thu, Jan 8, 2015 at 12:24 AM, Chen-Yu Tsai <wens@csie.org> wrote:
> > Hi,
> >
> > On Tue, Jan 6, 2015 at 11:24 PM, Eduardo Valentin <edubezval@gmail.com> wrote:
> >> Hello Chen-Yu,
> >>
> >>
> >> On Tue, Jan 06, 2015 at 10:35:13AM +0800, Chen-Yu Tsai wrote:
> >>> The touchscreen controller has a temperature sensor embedded in the SoC,
> >>> which already has hwmon support in the driver.
> >>>
> >>> Add DT thermal zone support so we can use it with cpufreq for thermal
> >>> throttling.
> >>>
> >>> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
> >>> ---
> >>>  .../bindings/input/touchscreen/sun4i.txt           |  1 +
> >>>  drivers/input/touchscreen/sun4i-ts.c               | 27 ++++++++++++++++++++++
> >>>  2 files changed, 28 insertions(+)
> >>>
> >>> diff --git a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
> >>> index aef57791f40b..7f1110adbd24 100644
> >>> --- a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
> >>> +++ b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
> >>> @@ -5,6 +5,7 @@ Required properties:
> >>>   - compatible: "allwinner,sun4i-a10-ts"
> >>>   - reg: mmio address range of the chip
> >>>   - interrupts: interrupt to which the chip is connected
> >>> + - #thermal-sensor-cells: shall be 0
> >>>
> >>
> >> You may want to update your Example section too, below.
> >> Example:
> >>
> >>         rtp: rtp@01c25000 {
> >>                 compatible = "allwinner,sun4i-a10-ts";
> >>                 reg = <0x01c25000 0x100>;
> >>                 interrupts = <29>;
> >>                 allwinner,ts-attached;
> >>                 #thermal-sensor-cells = <0>;
> >>         };
> >
> > Ok.
> >
> >>
> >>
> >>>  Optional properties:
> >>>   - allwinner,ts-attached: boolean indicating that an actual touchscreen is
> >>> diff --git a/drivers/input/touchscreen/sun4i-ts.c b/drivers/input/touchscreen/sun4i-ts.c
> >>> index 28a06749ae42..b6e9043446d6 100644
> >>> --- a/drivers/input/touchscreen/sun4i-ts.c
> >>> +++ b/drivers/input/touchscreen/sun4i-ts.c
> >>> @@ -34,6 +34,7 @@
> >>>
> >>>  #include <linux/err.h>
> >>>  #include <linux/hwmon.h>
> >>> +#include <linux/thermal.h>
> >>>  #include <linux/init.h>
> >>>  #include <linux/input.h>
> >>>  #include <linux/interrupt.h>
> >>> @@ -107,6 +108,7 @@
> >>>  struct sun4i_ts_data {
> >>>       struct device *dev;
> >>>       struct input_dev *input;
> >>> +     struct thermal_zone_device *tz;
> >>>       void __iomem *base;
> >>>       unsigned int irq;
> >>>       bool ignore_fifo_data;
> >>> @@ -180,6 +182,23 @@ static void sun4i_ts_close(struct input_dev *dev)
> >>>       writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
> >>>  }
> >>>
> >>> +static int get_temp(void *data, long *temp)
> >>> +{
> >>> +     struct sun4i_ts_data *ts = data;
> >>> +
> >>> +     /* No temp_data until the first irq */
> >>> +     if (ts->temp_data == -1)
> >>> +             return -EAGAIN;
> >>> +
> >>> +     *temp = (ts->temp_data - 1447) * 100;
> >>> +
> >>
> >> Care to explain the formula in a simple comment?
> >
> > This was just copied from the hwmon section. AFAIK there is no documentation
> > for the formula. It was probably copied from Allwinner's SDK code.
> >
> > Hans? Do you remember where you got this?
> 
> So this is from the AXP209 datasheet. The Allwinner SoC datasheets don't
> mention the formula to calculate the temperature. But since Allwinner
> and X-powers are affiliated, it's possible they use the same formula.
> 
> http://comments.gmane.org/gmane.comp.hardware.netbook.arm.sunxi/3838

Ok. We use in the thermal framework  miliCelsius as the temperature
unit. Can you make sure the resulting temperature is in miliCelsius?

Cheers,

> 
> >>> +     return 0;
> >>> +}
> >>> +
> >>> +static struct thermal_zone_of_device_ops sun4i_ts_tz_ops = {
> >>> +     .get_temp = get_temp,
> >>> +};
> >>> +
> >>>  static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
> >>>                        char *buf)
> >>>  {
> >>> @@ -288,6 +307,11 @@ static int sun4i_ts_probe(struct platform_device *pdev)
> >>>       if (IS_ERR(hwmon))
> >>>               return PTR_ERR(hwmon);
> >>>
> >>> +     ts->tz = thermal_zone_of_sensor_register(ts->dev, 0, ts,
> >>> +                                              &sun4i_ts_tz_ops);
> >>> +     if (IS_ERR(ts->tz))
> >>> +             ts->tz = NULL;
> >>> +
> >>>       writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
> >>>
> >>>       if (ts_attached) {
> >>
> >> here.. if input_register_device fails, you will keep an orphan thermal zone
> >> registered in your system:
> >>
> >>                 error = input_register_device(ts->input);
> >>                 if (error) {
> >>                         writel(0, ts->base + TP_INT_FIFOC);
> >
> > Will add an unregister call here.
> >
> >
> > Thanks for the review.
> >
> > ChenYu
> >
> >>                         return error;
> >>                 }
> >>                 ...
> >>
> >>
> >>> @@ -310,6 +334,9 @@ static int sun4i_ts_remove(struct platform_device *pdev)
> >>>       if (ts->input)
> >>>               input_unregister_device(ts->input);
> >>>
> >>> +     if (ts->tz)
> >>> +             thermal_zone_of_sensor_unregister(ts->dev, ts->tz);
> >>> +
> >>>       /* Deactivate all IRQs */
> >>>       writel(0, ts->base + TP_INT_FIFOC);
> >>>
> >>> --
> >>> 2.1.4
> >>>
Chen-Yu Tsai (Moxa) Jan. 9, 2015, 6:24 p.m. UTC | #5
On Sat, Jan 10, 2015 at 2:07 AM, Eduardo Valentin <edubezval@gmail.com> wrote:
> On Thu, Jan 08, 2015 at 09:33:54PM +0800, Chen-Yu Tsai wrote:
>> On Thu, Jan 8, 2015 at 12:24 AM, Chen-Yu Tsai <wens@csie.org> wrote:
>> > Hi,
>> >
>> > On Tue, Jan 6, 2015 at 11:24 PM, Eduardo Valentin <edubezval@gmail.com> wrote:
>> >> Hello Chen-Yu,
>> >>
>> >>
>> >> On Tue, Jan 06, 2015 at 10:35:13AM +0800, Chen-Yu Tsai wrote:
>> >>> The touchscreen controller has a temperature sensor embedded in the SoC,
>> >>> which already has hwmon support in the driver.
>> >>>
>> >>> Add DT thermal zone support so we can use it with cpufreq for thermal
>> >>> throttling.
>> >>>
>> >>> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
>> >>> ---
>> >>>  .../bindings/input/touchscreen/sun4i.txt           |  1 +
>> >>>  drivers/input/touchscreen/sun4i-ts.c               | 27 ++++++++++++++++++++++
>> >>>  2 files changed, 28 insertions(+)
>> >>>
>> >>> diff --git a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
>> >>> index aef57791f40b..7f1110adbd24 100644
>> >>> --- a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
>> >>> +++ b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
>> >>> @@ -5,6 +5,7 @@ Required properties:
>> >>>   - compatible: "allwinner,sun4i-a10-ts"
>> >>>   - reg: mmio address range of the chip
>> >>>   - interrupts: interrupt to which the chip is connected
>> >>> + - #thermal-sensor-cells: shall be 0
>> >>>
>> >>
>> >> You may want to update your Example section too, below.
>> >> Example:
>> >>
>> >>         rtp: rtp@01c25000 {
>> >>                 compatible = "allwinner,sun4i-a10-ts";
>> >>                 reg = <0x01c25000 0x100>;
>> >>                 interrupts = <29>;
>> >>                 allwinner,ts-attached;
>> >>                 #thermal-sensor-cells = <0>;
>> >>         };
>> >
>> > Ok.
>> >
>> >>
>> >>
>> >>>  Optional properties:
>> >>>   - allwinner,ts-attached: boolean indicating that an actual touchscreen is
>> >>> diff --git a/drivers/input/touchscreen/sun4i-ts.c b/drivers/input/touchscreen/sun4i-ts.c
>> >>> index 28a06749ae42..b6e9043446d6 100644
>> >>> --- a/drivers/input/touchscreen/sun4i-ts.c
>> >>> +++ b/drivers/input/touchscreen/sun4i-ts.c
>> >>> @@ -34,6 +34,7 @@
>> >>>
>> >>>  #include <linux/err.h>
>> >>>  #include <linux/hwmon.h>
>> >>> +#include <linux/thermal.h>
>> >>>  #include <linux/init.h>
>> >>>  #include <linux/input.h>
>> >>>  #include <linux/interrupt.h>
>> >>> @@ -107,6 +108,7 @@
>> >>>  struct sun4i_ts_data {
>> >>>       struct device *dev;
>> >>>       struct input_dev *input;
>> >>> +     struct thermal_zone_device *tz;
>> >>>       void __iomem *base;
>> >>>       unsigned int irq;
>> >>>       bool ignore_fifo_data;
>> >>> @@ -180,6 +182,23 @@ static void sun4i_ts_close(struct input_dev *dev)
>> >>>       writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
>> >>>  }
>> >>>
>> >>> +static int get_temp(void *data, long *temp)
>> >>> +{
>> >>> +     struct sun4i_ts_data *ts = data;
>> >>> +
>> >>> +     /* No temp_data until the first irq */
>> >>> +     if (ts->temp_data == -1)
>> >>> +             return -EAGAIN;
>> >>> +
>> >>> +     *temp = (ts->temp_data - 1447) * 100;
>> >>> +
>> >>
>> >> Care to explain the formula in a simple comment?
>> >
>> > This was just copied from the hwmon section. AFAIK there is no documentation
>> > for the formula. It was probably copied from Allwinner's SDK code.
>> >
>> > Hans? Do you remember where you got this?
>>
>> So this is from the AXP209 datasheet. The Allwinner SoC datasheets don't
>> mention the formula to calculate the temperature. But since Allwinner
>> and X-powers are affiliated, it's possible they use the same formula.
>>
>> http://comments.gmane.org/gmane.comp.hardware.netbook.arm.sunxi/3838
>
> Ok. We use in the thermal framework  miliCelsius as the temperature
> unit. Can you make sure the resulting temperature is in miliCelsius?

Yes the result is in miliCelsius.

>>
>> >>> +     return 0;
>> >>> +}
>> >>> +
>> >>> +static struct thermal_zone_of_device_ops sun4i_ts_tz_ops = {
>> >>> +     .get_temp = get_temp,
>> >>> +};
>> >>> +
>> >>>  static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
>> >>>                        char *buf)
>> >>>  {
>> >>> @@ -288,6 +307,11 @@ static int sun4i_ts_probe(struct platform_device *pdev)
>> >>>       if (IS_ERR(hwmon))
>> >>>               return PTR_ERR(hwmon);
>> >>>
>> >>> +     ts->tz = thermal_zone_of_sensor_register(ts->dev, 0, ts,
>> >>> +                                              &sun4i_ts_tz_ops);
>> >>> +     if (IS_ERR(ts->tz))
>> >>> +             ts->tz = NULL;
>> >>> +
>> >>>       writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
>> >>>
>> >>>       if (ts_attached) {
>> >>
>> >> here.. if input_register_device fails, you will keep an orphan thermal zone
>> >> registered in your system:
>> >>
>> >>                 error = input_register_device(ts->input);
>> >>                 if (error) {
>> >>                         writel(0, ts->base + TP_INT_FIFOC);
>> >
>> > Will add an unregister call here.
>> >
>> >
>> > Thanks for the review.
>> >
>> > ChenYu
>> >
>> >>                         return error;
>> >>                 }
>> >>                 ...
>> >>
>> >>
>> >>> @@ -310,6 +334,9 @@ static int sun4i_ts_remove(struct platform_device *pdev)
>> >>>       if (ts->input)
>> >>>               input_unregister_device(ts->input);
>> >>>
>> >>> +     if (ts->tz)
>> >>> +             thermal_zone_of_sensor_unregister(ts->dev, ts->tz);
>> >>> +
>> >>>       /* Deactivate all IRQs */
>> >>>       writel(0, ts->base + TP_INT_FIFOC);
>> >>>
>> >>> --
>> >>> 2.1.4
>> >>>

Patch
diff mbox

diff --git a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
index aef57791f40b..7f1110adbd24 100644
--- a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
+++ b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
@@ -5,6 +5,7 @@  Required properties:
  - compatible: "allwinner,sun4i-a10-ts"
  - reg: mmio address range of the chip
  - interrupts: interrupt to which the chip is connected
+ - #thermal-sensor-cells: shall be 0
 
 Optional properties:
  - allwinner,ts-attached: boolean indicating that an actual touchscreen is
diff --git a/drivers/input/touchscreen/sun4i-ts.c b/drivers/input/touchscreen/sun4i-ts.c
index 28a06749ae42..b6e9043446d6 100644
--- a/drivers/input/touchscreen/sun4i-ts.c
+++ b/drivers/input/touchscreen/sun4i-ts.c
@@ -34,6 +34,7 @@ 
 
 #include <linux/err.h>
 #include <linux/hwmon.h>
+#include <linux/thermal.h>
 #include <linux/init.h>
 #include <linux/input.h>
 #include <linux/interrupt.h>
@@ -107,6 +108,7 @@ 
 struct sun4i_ts_data {
 	struct device *dev;
 	struct input_dev *input;
+	struct thermal_zone_device *tz;
 	void __iomem *base;
 	unsigned int irq;
 	bool ignore_fifo_data;
@@ -180,6 +182,23 @@  static void sun4i_ts_close(struct input_dev *dev)
 	writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
 }
 
+static int get_temp(void *data, long *temp)
+{
+	struct sun4i_ts_data *ts = data;
+
+	/* No temp_data until the first irq */
+	if (ts->temp_data == -1)
+		return -EAGAIN;
+
+	*temp = (ts->temp_data - 1447) * 100;
+
+	return 0;
+}
+
+static struct thermal_zone_of_device_ops sun4i_ts_tz_ops = {
+	.get_temp = get_temp,
+};
+
 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
 			 char *buf)
 {
@@ -288,6 +307,11 @@  static int sun4i_ts_probe(struct platform_device *pdev)
 	if (IS_ERR(hwmon))
 		return PTR_ERR(hwmon);
 
+	ts->tz = thermal_zone_of_sensor_register(ts->dev, 0, ts,
+						 &sun4i_ts_tz_ops);
+	if (IS_ERR(ts->tz))
+		ts->tz = NULL;
+
 	writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
 
 	if (ts_attached) {
@@ -310,6 +334,9 @@  static int sun4i_ts_remove(struct platform_device *pdev)
 	if (ts->input)
 		input_unregister_device(ts->input);
 
+	if (ts->tz)
+		thermal_zone_of_sensor_unregister(ts->dev, ts->tz);
+
 	/* Deactivate all IRQs */
 	writel(0, ts->base + TP_INT_FIFOC);