[PATCH 0/3] touchscreen: sun4i-ts: A10 (sun4i) has a different temperature curve

[PATCH 0/3] touchscreen: sun4i-ts: A10 (sun4i) has a different temperature curve

[Hans de Goede]

Hi Dmitry, Maxime, et al.

Here is a patch-set for the sun4i-ts driver temperature sensor support,
it consists of 2 fixes:

1) Use a better temperature curve for A10 SoCs to avoid reporting a way to
high temperature.

2) Start with reporting an "estimated" temperature of 40 degrees rather then
returning -EAGAIN until we get the first temperature ready interrupt to avoid
the kernel tempzone core logging errors because of our -EAGAIN return.

Dmitry can you please queue up the 2 sun4i-ts patches for 4.1, and Maxime,
can you please queue up the matching dts change ?

Thanks & Regards,

Hans

[PATCH 1/3] touchscreen: sun4i-ts: A10 (sun4i) has a different temperature curve

[Hans de Goede]

Testing has revealed that the temperature in the rtp controller of the A10
(sun4i) SoC has a different curve then on the A13 (sun5i) and later models.

Add a new sun5i-a13-ts compatible to differentiate the newer models and
set the curve based on the compatible string.

The new curve is still not ideal on all A10-s, that seems to have to
do with there being a large spread between different A10-s out there,
the new curve us based on callibration results on 4 completely different
models:
                        raw min raw max temp min temp max stepsize offset
Tong Zhang's hackberry    2402    2680    45.0     80.0    0.125   -255.3
Hansg's Cubieboard        2207    2300    36.0     45.0    0.096   -175.8
Olliver's lime 1 (*):     2258    2537    48.3     87.1    0.139   -265.7
Olliver's lime 2 (*):     2222    2486    46.7     91.7    0.170   -331.0
*) from: http://linux-sunxi.org/Temperature_Calibration

Average all 4:                                             0.133   -257.0
Average without outliers (middle 2):                       0.132   -261.0

Since it is better to slightly overreport the temperature this patch uses
the average of all 4 as curve.

This fixes the temperature reported on the A10 being much higher then
expected.

Cc: Tong Zhang <lovewilliam-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: Olliver Schinagl <o.schinagl-U3FVU11NWA554TAoqtyWWQ@public.gmane.org>
Reported-by: Tong Zhang <lovewilliam-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Signed-off-by: Hans de Goede <hdegoede-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
---
 .../devicetree/bindings/input/touchscreen/sun4i.txt      |  3 ++-
 drivers/input/touchscreen/sun4i-ts.c                     | 16 +++++++++++++---
 2 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
index 433332d..d59d252 100644
--- a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
+++ b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
@@ -2,7 +2,8 @@ sun4i resistive touchscreen controller
 --------------------------------------
 
 Required properties:
- - compatible: "allwinner,sun4i-a10-ts" or "allwinner,sun6i-a31-ts"
+ - compatible: "allwinner,sun4i-a10-ts", "allwinner,sun5i-a13-ts" or
+   "allwinner,sun6i-a31-ts"
  - reg: mmio address range of the chip
  - interrupts: interrupt to which the chip is connected
  - #thermal-sensor-cells: shall be 0
diff --git a/drivers/input/touchscreen/sun4i-ts.c b/drivers/input/touchscreen/sun4i-ts.c
index b93a28b..66ccd5a 100644
--- a/drivers/input/touchscreen/sun4i-ts.c
+++ b/drivers/input/touchscreen/sun4i-ts.c
@@ -258,6 +258,15 @@ static int sun4i_ts_probe(struct platform_device *pdev)
 		/* Allwinner SDK has temperature = -271 + (value / 6) (C) */
 		ts->temp_offset = 1626;
 		ts->temp_step = 167;
+	} else if (of_device_is_compatible(np, "allwinner,sun4i-a10-ts")) {
+		/*
+		 * The A10 temperature sensor has quite a wide spread, these
+		 * parameters are based on the averaging of the calibration
+		 * results of 4 completely different boards, with a spread of
+		 * temp_step from 96 - 170 and temp_offset from 1758 - 3310.
+		 */
+		ts->temp_offset = 2570;
+		ts->temp_step = 133;
 	} else {
 		/*
 		 * The user manuals do not contain the formula for calculating
@@ -330,10 +339,10 @@ static int sun4i_ts_probe(struct platform_device *pdev)
 	 * finally enable tp mode.
 	 */
 	reg = STYLUS_UP_DEBOUN(5) | STYLUS_UP_DEBOUN_EN(1);
-	if (of_device_is_compatible(np, "allwinner,sun4i-a10-ts"))
-		reg |= TP_MODE_EN(1);
-	else
+	if (of_device_is_compatible(np, "allwinner,sun6i-a31-ts"))
 		reg |= SUN6I_TP_MODE_EN(1);
+	else
+		reg |= TP_MODE_EN(1);
 	writel(reg, ts->base + TP_CTRL1);
 
 	/*
@@ -383,6 +392,7 @@ static int sun4i_ts_remove(struct platform_device *pdev)
 
 static const struct of_device_id sun4i_ts_of_match[] = {
 	{ .compatible = "allwinner,sun4i-a10-ts", },
+	{ .compatible = "allwinner,sun5i-a13-ts", },
 	{ .compatible = "allwinner,sun6i-a31-ts", },
 	{ /* sentinel */ }
 };
-- 
2.3.1

Re: [PATCH 1/3] touchscreen: sun4i-ts: A10 (sun4i) has a different temperature curve

[Dmitry Torokhov]

On Sun, Mar 08, 2015 at 09:53:40PM +0100, Hans de Goede wrote:
> Testing has revealed that the temperature in the rtp controller of the A10
> (sun4i) SoC has a different curve then on the A13 (sun5i) and later models.
> 
> Add a new sun5i-a13-ts compatible to differentiate the newer models and
> set the curve based on the compatible string.
> 
> The new curve is still not ideal on all A10-s, that seems to have to
> do with there being a large spread between different A10-s out there,
> the new curve us based on callibration results on 4 completely different
> models:
>                         raw min raw max temp min temp max stepsize offset
> Tong Zhang's hackberry    2402    2680    45.0     80.0    0.125   -255.3
> Hansg's Cubieboard        2207    2300    36.0     45.0    0.096   -175.8
> Olliver's lime 1 (*):     2258    2537    48.3     87.1    0.139   -265.7
> Olliver's lime 2 (*):     2222    2486    46.7     91.7    0.170   -331.0
> *) from: http://linux-sunxi.org/Temperature_Calibration
> 
> Average all 4:                                             0.133   -257.0
> Average without outliers (middle 2):                       0.132   -261.0
> 
> Since it is better to slightly overreport the temperature this patch uses
> the average of all 4 as curve.
> 
> This fixes the temperature reported on the A10 being much higher then
> expected.
> 
> Cc: Tong Zhang <lovewilliam-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> Cc: Olliver Schinagl <o.schinagl-U3FVU11NWA554TAoqtyWWQ@public.gmane.org>
> Reported-by: Tong Zhang <lovewilliam-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> Signed-off-by: Hans de Goede <hdegoede-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>


Applied, thank you.

> ---
>  .../devicetree/bindings/input/touchscreen/sun4i.txt      |  3 ++-
>  drivers/input/touchscreen/sun4i-ts.c                     | 16 +++++++++++++---
>  2 files changed, 15 insertions(+), 4 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
> index 433332d..d59d252 100644
> --- a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
> +++ b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
> @@ -2,7 +2,8 @@ sun4i resistive touchscreen controller
>  --------------------------------------
>  
>  Required properties:
> - - compatible: "allwinner,sun4i-a10-ts" or "allwinner,sun6i-a31-ts"
> + - compatible: "allwinner,sun4i-a10-ts", "allwinner,sun5i-a13-ts" or
> +   "allwinner,sun6i-a31-ts"
>   - reg: mmio address range of the chip
>   - interrupts: interrupt to which the chip is connected
>   - #thermal-sensor-cells: shall be 0
> diff --git a/drivers/input/touchscreen/sun4i-ts.c b/drivers/input/touchscreen/sun4i-ts.c
> index b93a28b..66ccd5a 100644
> --- a/drivers/input/touchscreen/sun4i-ts.c
> +++ b/drivers/input/touchscreen/sun4i-ts.c
> @@ -258,6 +258,15 @@ static int sun4i_ts_probe(struct platform_device *pdev)
>  		/* Allwinner SDK has temperature = -271 + (value / 6) (C) */
>  		ts->temp_offset = 1626;
>  		ts->temp_step = 167;
> +	} else if (of_device_is_compatible(np, "allwinner,sun4i-a10-ts")) {
> +		/*
> +		 * The A10 temperature sensor has quite a wide spread, these
> +		 * parameters are based on the averaging of the calibration
> +		 * results of 4 completely different boards, with a spread of
> +		 * temp_step from 96 - 170 and temp_offset from 1758 - 3310.
> +		 */
> +		ts->temp_offset = 2570;
> +		ts->temp_step = 133;
>  	} else {
>  		/*
>  		 * The user manuals do not contain the formula for calculating
> @@ -330,10 +339,10 @@ static int sun4i_ts_probe(struct platform_device *pdev)
>  	 * finally enable tp mode.
>  	 */
>  	reg = STYLUS_UP_DEBOUN(5) | STYLUS_UP_DEBOUN_EN(1);
> -	if (of_device_is_compatible(np, "allwinner,sun4i-a10-ts"))
> -		reg |= TP_MODE_EN(1);
> -	else
> +	if (of_device_is_compatible(np, "allwinner,sun6i-a31-ts"))
>  		reg |= SUN6I_TP_MODE_EN(1);
> +	else
> +		reg |= TP_MODE_EN(1);
>  	writel(reg, ts->base + TP_CTRL1);
>  
>  	/*
> @@ -383,6 +392,7 @@ static int sun4i_ts_remove(struct platform_device *pdev)
>  
>  static const struct of_device_id sun4i_ts_of_match[] = {
>  	{ .compatible = "allwinner,sun4i-a10-ts", },
> +	{ .compatible = "allwinner,sun5i-a13-ts", },
>  	{ .compatible = "allwinner,sun6i-a31-ts", },
>  	{ /* sentinel */ }
>  };
> -- 
> 2.3.1
> 

-- 
Dmitry

Re: [PATCH 1/3] touchscreen: sun4i-ts: A10 (sun4i) has a different temperature curve

[Hans de Goede]

Hi,

On 08-03-15 22:13, Dmitry Torokhov wrote:
> On Sun, Mar 08, 2015 at 09:53:40PM +0100, Hans de Goede wrote:
>> Testing has revealed that the temperature in the rtp controller of the A10
>> (sun4i) SoC has a different curve then on the A13 (sun5i) and later models.
>>
>> Add a new sun5i-a13-ts compatible to differentiate the newer models and
>> set the curve based on the compatible string.
>>
>> The new curve is still not ideal on all A10-s, that seems to have to
>> do with there being a large spread between different A10-s out there,
>> the new curve us based on callibration results on 4 completely different
>> models:
>>                          raw min raw max temp min temp max stepsize offset
>> Tong Zhang's hackberry    2402    2680    45.0     80.0    0.125   -255.3
>> Hansg's Cubieboard        2207    2300    36.0     45.0    0.096   -175.8
>> Olliver's lime 1 (*):     2258    2537    48.3     87.1    0.139   -265.7
>> Olliver's lime 2 (*):     2222    2486    46.7     91.7    0.170   -331.0
>> *) from: http://linux-sunxi.org/Temperature_Calibration
>>
>> Average all 4:                                             0.133   -257.0
>> Average without outliers (middle 2):                       0.132   -261.0
>>
>> Since it is better to slightly overreport the temperature this patch uses
>> the average of all 4 as curve.
>>
>> This fixes the temperature reported on the A10 being much higher then
>> expected.
>>
>> Cc: Tong Zhang <lovewilliam-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
>> Cc: Olliver Schinagl <o.schinagl-U3FVU11NWA554TAoqtyWWQ@public.gmane.org>
>> Reported-by: Tong Zhang <lovewilliam-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
>> Signed-off-by: Hans de Goede <hdegoede-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
>
>
> Applied, thank you.

Thanks.

Note I've just found out that I've made a math error, the offset as I've used it is
in degrees, but the actual code applies the offset before multiplying by stepsize :|

Given that this is rather backwards (every math course ever thought applies
the multiplication before the offset for linear functions. I'll do a follow up
patch fixing the code to do the logical thing, and adjusting the offset for
the other models accordingly.

Regards,

Hans



>
>> ---
>>   .../devicetree/bindings/input/touchscreen/sun4i.txt      |  3 ++-
>>   drivers/input/touchscreen/sun4i-ts.c                     | 16 +++++++++++++---
>>   2 files changed, 15 insertions(+), 4 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
>> index 433332d..d59d252 100644
>> --- a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
>> +++ b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
>> @@ -2,7 +2,8 @@ sun4i resistive touchscreen controller
>>   --------------------------------------
>>
>>   Required properties:
>> - - compatible: "allwinner,sun4i-a10-ts" or "allwinner,sun6i-a31-ts"
>> + - compatible: "allwinner,sun4i-a10-ts", "allwinner,sun5i-a13-ts" or
>> +   "allwinner,sun6i-a31-ts"
>>    - reg: mmio address range of the chip
>>    - interrupts: interrupt to which the chip is connected
>>    - #thermal-sensor-cells: shall be 0
>> diff --git a/drivers/input/touchscreen/sun4i-ts.c b/drivers/input/touchscreen/sun4i-ts.c
>> index b93a28b..66ccd5a 100644
>> --- a/drivers/input/touchscreen/sun4i-ts.c
>> +++ b/drivers/input/touchscreen/sun4i-ts.c
>> @@ -258,6 +258,15 @@ static int sun4i_ts_probe(struct platform_device *pdev)
>>   		/* Allwinner SDK has temperature = -271 + (value / 6) (C) */
>>   		ts->temp_offset = 1626;
>>   		ts->temp_step = 167;
>> +	} else if (of_device_is_compatible(np, "allwinner,sun4i-a10-ts")) {
>> +		/*
>> +		 * The A10 temperature sensor has quite a wide spread, these
>> +		 * parameters are based on the averaging of the calibration
>> +		 * results of 4 completely different boards, with a spread of
>> +		 * temp_step from 96 - 170 and temp_offset from 1758 - 3310.
>> +		 */
>> +		ts->temp_offset = 2570;
>> +		ts->temp_step = 133;
>>   	} else {
>>   		/*
>>   		 * The user manuals do not contain the formula for calculating
>> @@ -330,10 +339,10 @@ static int sun4i_ts_probe(struct platform_device *pdev)
>>   	 * finally enable tp mode.
>>   	 */
>>   	reg = STYLUS_UP_DEBOUN(5) | STYLUS_UP_DEBOUN_EN(1);
>> -	if (of_device_is_compatible(np, "allwinner,sun4i-a10-ts"))
>> -		reg |= TP_MODE_EN(1);
>> -	else
>> +	if (of_device_is_compatible(np, "allwinner,sun6i-a31-ts"))
>>   		reg |= SUN6I_TP_MODE_EN(1);
>> +	else
>> +		reg |= TP_MODE_EN(1);
>>   	writel(reg, ts->base + TP_CTRL1);
>>
>>   	/*
>> @@ -383,6 +392,7 @@ static int sun4i_ts_remove(struct platform_device *pdev)
>>
>>   static const struct of_device_id sun4i_ts_of_match[] = {
>>   	{ .compatible = "allwinner,sun4i-a10-ts", },
>> +	{ .compatible = "allwinner,sun5i-a13-ts", },
>>   	{ .compatible = "allwinner,sun6i-a31-ts", },
>>   	{ /* sentinel */ }
>>   };
>> --
>> 2.3.1
>>
>

[PATCH 2/3] touchscreen: sun4i-ts: Do not report -EAGAIN from tempzone callback

[Hans de Goede]

Returning -EAGAIN while waiting for the first temperature ready interrupt,
causes the tempzone core to log the following errors:

[    1.219353] thermal thermal_zone0: failed to read out thermal zone 0
[    2.015433] thermal thermal_zone0: failed to read out thermal zone 0
[    2.416737] thermal thermal_zone0: failed to read out thermal zone 0

So instead of returning -EAGAIN, return an intial temperature estimate of
40 degrees, and a success status.

Signed-off-by: Hans de Goede <hdegoede-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
---
 drivers/input/touchscreen/sun4i-ts.c | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/drivers/input/touchscreen/sun4i-ts.c b/drivers/input/touchscreen/sun4i-ts.c
index 66ccd5a..d641b12 100644
--- a/drivers/input/touchscreen/sun4i-ts.c
+++ b/drivers/input/touchscreen/sun4i-ts.c
@@ -189,12 +189,7 @@ static void sun4i_ts_close(struct input_dev *dev)
 
 static int sun4i_get_temp(const struct sun4i_ts_data *ts, long *temp)
 {
-	/* No temp_data until the first irq */
-	if (ts->temp_data == -1)
-		return -EAGAIN;
-
 	*temp = (ts->temp_data - ts->temp_offset) * ts->temp_step;
-
 	return 0;
 }
 
@@ -212,11 +207,8 @@ static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
 {
 	struct sun4i_ts_data *ts = dev_get_drvdata(dev);
 	long temp;
-	int error;
 
-	error = sun4i_get_temp(ts, &temp);
-	if (error)
-		return error;
+	sun4i_get_temp(ts, &temp);
 
 	return sprintf(buf, "%ld\n", temp);
 }
@@ -253,7 +245,7 @@ static int sun4i_ts_probe(struct platform_device *pdev)
 
 	ts->dev = dev;
 	ts->ignore_fifo_data = true;
-	ts->temp_data = -1;
+
 	if (of_device_is_compatible(np, "allwinner,sun6i-a31-ts")) {
 		/* Allwinner SDK has temperature = -271 + (value / 6) (C) */
 		ts->temp_offset = 1626;
@@ -283,6 +275,13 @@ static int sun4i_ts_probe(struct platform_device *pdev)
 		ts->temp_step = 100;
 	}
 
+	/*
+	 * Start by reporting 40 degrees as temperature, this avoids
+	 * "thermal_zone: failed to read out thermal zone" errors while
+	 * waiting for the first temp ready irq.
+	 */
+	ts->temp_data = ts->temp_offset + 40000 / ts->temp_step;
+
 	ts_attached = of_property_read_bool(np, "allwinner,ts-attached");
 	if (ts_attached) {
 		ts->input = devm_input_allocate_device(dev);
-- 
2.3.1

[PATCH 3/3] ARM: dts: sunxi: Adjust touchscreen compatible for sun5i and later

[Hans de Goede]

The touchscreen controller in the A13 and later has a different temperature
curve than the one in the original A10, change the compatible for the A13 and
later so that the kernel will use the correct curve.

Reported-by: Tong Zhang <lovewilliam-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Signed-off-by: Hans de Goede <hdegoede-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
---
 arch/arm/boot/dts/sun5i.dtsi     | 2 +-
 arch/arm/boot/dts/sun7i-a20.dtsi | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/boot/dts/sun5i.dtsi b/arch/arm/boot/dts/sun5i.dtsi
index e42cbb0..610ea18 100644
--- a/arch/arm/boot/dts/sun5i.dtsi
+++ b/arch/arm/boot/dts/sun5i.dtsi
@@ -494,7 +494,7 @@
 		};
 
 		rtp: rtp@01c25000 {
-			compatible = "allwinner,sun4i-a10-ts";
+			compatible = "allwinner,sun5i-a13-ts";
 			reg = <0x01c25000 0x100>;
 			interrupts = <29>;
 			#thermal-sensor-cells = <0>;
diff --git a/arch/arm/boot/dts/sun7i-a20.dtsi b/arch/arm/boot/dts/sun7i-a20.dtsi
index 3a8530b..8df77f5 100644
--- a/arch/arm/boot/dts/sun7i-a20.dtsi
+++ b/arch/arm/boot/dts/sun7i-a20.dtsi
@@ -1043,7 +1043,7 @@
 		};
 
 		rtp: rtp@01c25000 {
-			compatible = "allwinner,sun4i-a10-ts";
+			compatible = "allwinner,sun5i-a13-ts";
 			reg = <0x01c25000 0x100>;
 			interrupts = <GIC_SPI 29 IRQ_TYPE_LEVEL_HIGH>;
 			#thermal-sensor-cells = <0>;
-- 
2.3.1

Re: [PATCH 3/3] ARM: dts: sunxi: Adjust touchscreen compatible for sun5i and later

[Maxime Ripard]

[-- Attachment #1: Type: text/plain, Size: 574 bytes --]

On Sun, Mar 08, 2015 at 09:53:42PM +0100, Hans de Goede wrote:
> The touchscreen controller in the A13 and later has a different temperature
> curve than the one in the original A10, change the compatible for the A13 and
> later so that the kernel will use the correct curve.
> 
> Reported-by: Tong Zhang <lovewilliam-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> Signed-off-by: Hans de Goede <hdegoede-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>

Applied, thanks!

Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

Re: [PATCH 0/3] touchscreen: sun4i-ts: A10 (sun4i) has a different temperature curve

[Dmitry Torokhov]

Hi Hans,

On Sun, Mar 08, 2015 at 09:53:39PM +0100, Hans de Goede wrote:
> Hi Dmitry, Maxime, et al.
> 
> Here is a patch-set for the sun4i-ts driver temperature sensor support,
> it consists of 2 fixes:
> 
> 1) Use a better temperature curve for A10 SoCs to avoid reporting a way to
> high temperature.
> 
> 2) Start with reporting an "estimated" temperature of 40 degrees rather then
> returning -EAGAIN until we get the first temperature ready interrupt to avoid
> the kernel tempzone core logging errors because of our -EAGAIN return.

No, I think we better teach thermal core not to complain about
-EAGAINs.

> 
> Dmitry can you please queue up the 2 sun4i-ts patches for 4.1, and Maxime,
> can you please queue up the matching dts change ?
> 
> Thanks & Regards,
> 
> Hans

-- 
Dmitry

Re: [PATCH 0/3] touchscreen: sun4i-ts: A10 (sun4i) has a different temperature curve

[Hans de Goede]

Hi,

On 08-03-15 22:11, Dmitry Torokhov wrote:
> Hi Hans,
>
> On Sun, Mar 08, 2015 at 09:53:39PM +0100, Hans de Goede wrote:
>> Hi Dmitry, Maxime, et al.
>>
>> Here is a patch-set for the sun4i-ts driver temperature sensor support,
>> it consists of 2 fixes:
>>
>> 1) Use a better temperature curve for A10 SoCs to avoid reporting a way to
>> high temperature.
>>
>> 2) Start with reporting an "estimated" temperature of 40 degrees rather then
>> returning -EAGAIN until we get the first temperature ready interrupt to avoid
>> the kernel tempzone core logging errors because of our -EAGAIN return.
>
> No, I think we better teach thermal core not to complain about
> -EAGAINs.

I was wondering if that would not be a better fix myself, so ack. I'll go do
a patch for that and submit it to the thermalzone maintainer.

Regards,

Hans