[PATCH 0/7] Add support for H6 thermal sensor

[PATCH 0/7] Add support for H6 thermal sensor

[Yangtao Li]

This patchset adds support for the H6 ths sensor.

Based on IIO-based thermal sensor driver for Allwinner H3 and A83T SoC,
thx to Philipp Rossak's work.

TODO: calibrate thermal sensor by using information from sid.

Yangtao Li (7):
  iio: adc: sun4i-gpadc: rework for support multiple thermal sensor
  iio: adc: sun4i-gpadc: introduce temp_data in gpadc_data
  iio: adc: sun4i-gpadc: introduce gpadc_enable and gpadc_disable in
    gpadc_data
  iio: adc: sun4i-gpadc-iio: support clocks and reset
  dt-bindings: mfd: Add H6 GPADC binding
  iio: adc: sun4i-gpadc-iio: add support for H6 thermal sensor
  iio: adc: sun4i-gpadc-iio convert to SPDX license tags

 .../devicetree/bindings/mfd/sun4i-gpadc.txt   |  27 ++-
 drivers/iio/adc/sun4i-gpadc-iio.c             | 208 +++++++++++++++---
 include/linux/mfd/sun4i-gpadc.h               |   9 +
 3 files changed, 213 insertions(+), 31 deletions(-)

-- 
2.17.1

[PATCH 1/7] iio: adc: sun4i-gpadc: rework for support multiple thermal sensor

[Yangtao Li]

For some SOCs, there are more than one thermal sensor, and there are
currently four sensors on the A80. So we need to do some work in order
to support multiple thermal sensors:

  1) add sensor_count in gpadc_data.
  2) introduce sun4i_sensor_tzd in sun4i_gpadc_iio, to support multiple
     thermal_zone_device and distinguish between different sensors.
  3) modify read temperature and initialization function.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
---
 drivers/iio/adc/sun4i-gpadc-iio.c | 61 +++++++++++++++++++++++--------
 1 file changed, 45 insertions(+), 16 deletions(-)

diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c
index 04d7147e0110..844fd52bd22f 100644
--- a/drivers/iio/adc/sun4i-gpadc-iio.c
+++ b/drivers/iio/adc/sun4i-gpadc-iio.c
@@ -56,6 +56,7 @@ struct gpadc_data {
 	unsigned int	tp_adc_select;
 	unsigned int	(*adc_chan_select)(unsigned int chan);
 	unsigned int	adc_chan_mask;
+	unsigned int    sensor_count;
 };
 
 static const struct gpadc_data sun4i_gpadc_data = {
@@ -65,6 +66,7 @@ static const struct gpadc_data sun4i_gpadc_data = {
 	.tp_adc_select = SUN4I_GPADC_CTRL1_TP_ADC_SELECT,
 	.adc_chan_select = &sun4i_gpadc_chan_select,
 	.adc_chan_mask = SUN4I_GPADC_CTRL1_ADC_CHAN_MASK,
+	.sensor_count = 1,
 };
 
 static const struct gpadc_data sun5i_gpadc_data = {
@@ -74,6 +76,7 @@ static const struct gpadc_data sun5i_gpadc_data = {
 	.tp_adc_select = SUN4I_GPADC_CTRL1_TP_ADC_SELECT,
 	.adc_chan_select = &sun4i_gpadc_chan_select,
 	.adc_chan_mask = SUN4I_GPADC_CTRL1_ADC_CHAN_MASK,
+	.sensor_count = 1,
 };
 
 static const struct gpadc_data sun6i_gpadc_data = {
@@ -83,14 +86,24 @@ static const struct gpadc_data sun6i_gpadc_data = {
 	.tp_adc_select = SUN6I_GPADC_CTRL1_TP_ADC_SELECT,
 	.adc_chan_select = &sun6i_gpadc_chan_select,
 	.adc_chan_mask = SUN6I_GPADC_CTRL1_ADC_CHAN_MASK,
+	.sensor_count = 1,
 };
 
 static const struct gpadc_data sun8i_a33_gpadc_data = {
 	.temp_offset = -1662,
 	.temp_scale = 162,
 	.tp_mode_en = SUN8I_GPADC_CTRL1_CHOP_TEMP_EN,
+	.sensor_count = 1,
 };
 
+struct sun4i_sensor_tzd {
+	struct sun4i_gpadc_iio          *info;
+	struct thermal_zone_device      *tzd;
+	unsigned int                    sensor_id;
+};
+
+#define MAX_SENSOR_COUNT	4
+
 struct sun4i_gpadc_iio {
 	struct iio_dev			*indio_dev;
 	struct completion		completion;
@@ -105,7 +118,7 @@ struct sun4i_gpadc_iio {
 	bool				no_irq;
 	/* prevents concurrent reads of temperature and ADC */
 	struct mutex			mutex;
-	struct thermal_zone_device	*tzd;
+	struct sun4i_sensor_tzd         tzds[MAX_SENSOR_COUNT];
 	struct device			*sensor_device;
 };
 
@@ -270,7 +283,8 @@ static int sun4i_gpadc_adc_read(struct iio_dev *indio_dev, int channel,
 	return sun4i_gpadc_read(indio_dev, channel, val, info->fifo_data_irq);
 }
 
-static int sun4i_gpadc_temp_read(struct iio_dev *indio_dev, int *val)
+static int sun4i_gpadc_temp_read(struct iio_dev *indio_dev, int *val,
+				 unsigned int sensor)
 {
 	struct sun4i_gpadc_iio *info = iio_priv(indio_dev);
 
@@ -324,7 +338,7 @@ static int sun4i_gpadc_read_raw(struct iio_dev *indio_dev,
 			ret = sun4i_gpadc_adc_read(indio_dev, chan->channel,
 						   val);
 		else
-			ret = sun4i_gpadc_temp_read(indio_dev, val);
+			ret = sun4i_gpadc_temp_read(indio_dev, val, 0);
 
 		if (ret)
 			return ret;
@@ -417,10 +431,11 @@ static int sun4i_gpadc_runtime_resume(struct device *dev)
 
 static int sun4i_gpadc_get_temp(void *data, int *temp)
 {
-	struct sun4i_gpadc_iio *info = data;
+	struct sun4i_sensor_tzd *tzd = data;
+	struct sun4i_gpadc_iio *info = tzd->info;
 	int val, scale, offset;
 
-	if (sun4i_gpadc_temp_read(info->indio_dev, &val))
+	if (sun4i_gpadc_temp_read(info->indio_dev, &val, tzd->sensor_id))
 		return -ETIMEDOUT;
 
 	sun4i_gpadc_temp_scale(info->indio_dev, &scale);
@@ -609,6 +624,28 @@ static int sun4i_gpadc_probe_mfd(struct platform_device *pdev,
 	return 0;
 }
 
+static int sun4i_sensor_init(struct sun4i_gpadc_iio *info)
+{
+	int i = 0;
+
+	for (; i < info->data->sensor_count; i++) {
+		info->tzds[i].info = info;
+		info->tzds[i].sensor_id = i;
+		info->tzds[i].tzd = devm_thermal_zone_of_sensor_register(
+					info->sensor_device, i, &info->tzds[i],
+					&sun4i_ts_tz_ops);
+
+		if (IS_ERR(info->tzds[i].tzd)) {
+			dev_err(info->sensor_device,
+				"could not register thermal sensor: %ld\n",
+				PTR_ERR(info->tzds[i].tzd));
+			return PTR_ERR(info->tzds[i].tzd);
+		}
+	}
+
+	return 0;
+}
+
 static int sun4i_gpadc_probe(struct platform_device *pdev)
 {
 	struct sun4i_gpadc_iio *info;
@@ -646,19 +683,13 @@ static int sun4i_gpadc_probe(struct platform_device *pdev)
 	pm_runtime_enable(&pdev->dev);
 
 	if (IS_ENABLED(CONFIG_THERMAL_OF)) {
-		info->tzd = thermal_zone_of_sensor_register(info->sensor_device,
-							    0, info,
-							    &sun4i_ts_tz_ops);
+		ret = sun4i_sensor_init(info);
 		/*
 		 * Do not fail driver probing when failing to register in
 		 * thermal because no thermal DT node is found.
 		 */
-		if (IS_ERR(info->tzd) && PTR_ERR(info->tzd) != -ENODEV) {
-			dev_err(&pdev->dev,
-				"could not register thermal sensor: %ld\n",
-				PTR_ERR(info->tzd));
-			return PTR_ERR(info->tzd);
-		}
+		if (ret && ret != -ENODEV)
+			return ret;
 	}
 
 	ret = devm_iio_device_register(&pdev->dev, indio_dev);
@@ -690,8 +721,6 @@ static int sun4i_gpadc_remove(struct platform_device *pdev)
 	if (!IS_ENABLED(CONFIG_THERMAL_OF))
 		return 0;
 
-	thermal_zone_of_sensor_unregister(info->sensor_device, info->tzd);
-
 	if (!info->no_irq)
 		iio_map_array_unregister(indio_dev);
 
-- 
2.17.1

Re: [PATCH 1/7] iio: adc: sun4i-gpadc: rework for support multiple thermal sensor

[Jonathan Cameron]

On Fri,  3 May 2019 03:28:07 -0400
Yangtao Li <tiny.windzz@gmail.com> wrote:

> For some SOCs, there are more than one thermal sensor, and there are
> currently four sensors on the A80. So we need to do some work in order
> to support multiple thermal sensors:
> 
>   1) add sensor_count in gpadc_data.
>   2) introduce sun4i_sensor_tzd in sun4i_gpadc_iio, to support multiple
>      thermal_zone_device and distinguish between different sensors.
>   3) modify read temperature and initialization function.
This comment doesn't mention the devm change. If it had it would have
raised immediate alarm bells.

I'm also not keen on the web of pointers that this driver is steadily
evolving.  I can't immediately see how to reduce that complexity however.

Jonathan

> 
> Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
> ---
>  drivers/iio/adc/sun4i-gpadc-iio.c | 61 +++++++++++++++++++++++--------
>  1 file changed, 45 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c
> index 04d7147e0110..844fd52bd22f 100644
> --- a/drivers/iio/adc/sun4i-gpadc-iio.c
> +++ b/drivers/iio/adc/sun4i-gpadc-iio.c
> @@ -56,6 +56,7 @@ struct gpadc_data {
>  	unsigned int	tp_adc_select;
>  	unsigned int	(*adc_chan_select)(unsigned int chan);
>  	unsigned int	adc_chan_mask;
> +	unsigned int    sensor_count;
>  };
>  
>  static const struct gpadc_data sun4i_gpadc_data = {
> @@ -65,6 +66,7 @@ static const struct gpadc_data sun4i_gpadc_data = {
>  	.tp_adc_select = SUN4I_GPADC_CTRL1_TP_ADC_SELECT,
>  	.adc_chan_select = &sun4i_gpadc_chan_select,
>  	.adc_chan_mask = SUN4I_GPADC_CTRL1_ADC_CHAN_MASK,
> +	.sensor_count = 1,
>  };
>  
>  static const struct gpadc_data sun5i_gpadc_data = {
> @@ -74,6 +76,7 @@ static const struct gpadc_data sun5i_gpadc_data = {
>  	.tp_adc_select = SUN4I_GPADC_CTRL1_TP_ADC_SELECT,
>  	.adc_chan_select = &sun4i_gpadc_chan_select,
>  	.adc_chan_mask = SUN4I_GPADC_CTRL1_ADC_CHAN_MASK,
> +	.sensor_count = 1,
>  };
>  
>  static const struct gpadc_data sun6i_gpadc_data = {
> @@ -83,14 +86,24 @@ static const struct gpadc_data sun6i_gpadc_data = {
>  	.tp_adc_select = SUN6I_GPADC_CTRL1_TP_ADC_SELECT,
>  	.adc_chan_select = &sun6i_gpadc_chan_select,
>  	.adc_chan_mask = SUN6I_GPADC_CTRL1_ADC_CHAN_MASK,
> +	.sensor_count = 1,
>  };
>  
>  static const struct gpadc_data sun8i_a33_gpadc_data = {
>  	.temp_offset = -1662,
>  	.temp_scale = 162,
>  	.tp_mode_en = SUN8I_GPADC_CTRL1_CHOP_TEMP_EN,
> +	.sensor_count = 1,
>  };
>  
> +struct sun4i_sensor_tzd {
> +	struct sun4i_gpadc_iio          *info;
> +	struct thermal_zone_device      *tzd;
> +	unsigned int                    sensor_id;
> +};
> +
> +#define MAX_SENSOR_COUNT	4
> +
>  struct sun4i_gpadc_iio {
>  	struct iio_dev			*indio_dev;
>  	struct completion		completion;
> @@ -105,7 +118,7 @@ struct sun4i_gpadc_iio {
>  	bool				no_irq;
>  	/* prevents concurrent reads of temperature and ADC */
>  	struct mutex			mutex;
> -	struct thermal_zone_device	*tzd;
> +	struct sun4i_sensor_tzd         tzds[MAX_SENSOR_COUNT];
>  	struct device			*sensor_device;
>  };
>  
> @@ -270,7 +283,8 @@ static int sun4i_gpadc_adc_read(struct iio_dev *indio_dev, int channel,
>  	return sun4i_gpadc_read(indio_dev, channel, val, info->fifo_data_irq);
>  }
>  
> -static int sun4i_gpadc_temp_read(struct iio_dev *indio_dev, int *val)
> +static int sun4i_gpadc_temp_read(struct iio_dev *indio_dev, int *val,
> +				 unsigned int sensor)
>  {
>  	struct sun4i_gpadc_iio *info = iio_priv(indio_dev);
>  
> @@ -324,7 +338,7 @@ static int sun4i_gpadc_read_raw(struct iio_dev *indio_dev,
>  			ret = sun4i_gpadc_adc_read(indio_dev, chan->channel,
>  						   val);
>  		else
> -			ret = sun4i_gpadc_temp_read(indio_dev, val);
> +			ret = sun4i_gpadc_temp_read(indio_dev, val, 0);
>  
>  		if (ret)
>  			return ret;
> @@ -417,10 +431,11 @@ static int sun4i_gpadc_runtime_resume(struct device *dev)
>  
>  static int sun4i_gpadc_get_temp(void *data, int *temp)
>  {
> -	struct sun4i_gpadc_iio *info = data;
> +	struct sun4i_sensor_tzd *tzd = data;
> +	struct sun4i_gpadc_iio *info = tzd->info;
>  	int val, scale, offset;
>  
> -	if (sun4i_gpadc_temp_read(info->indio_dev, &val))
> +	if (sun4i_gpadc_temp_read(info->indio_dev, &val, tzd->sensor_id))
>  		return -ETIMEDOUT;
>  
>  	sun4i_gpadc_temp_scale(info->indio_dev, &scale);
> @@ -609,6 +624,28 @@ static int sun4i_gpadc_probe_mfd(struct platform_device *pdev,
>  	return 0;
>  }
>  
> +static int sun4i_sensor_init(struct sun4i_gpadc_iio *info)
> +{
> +	int i = 0;
> +
> +	for (; i < info->data->sensor_count; i++) {
> +		info->tzds[i].info = info;
> +		info->tzds[i].sensor_id = i;
> +		info->tzds[i].tzd = devm_thermal_zone_of_sensor_register(
> +					info->sensor_device, i, &info->tzds[i],
> +					&sun4i_ts_tz_ops);

Using devm here has the result that the thermal_zones are remove 'after'
the end of the remove function for this driver.  That means you have
them still registered after several other commands are run in the remove
function.

Please ensure that the probe and remove orders are mirror images of each
other. Here it doesn't make a huge amount of actual difference but
it does make the code harder to reason about.

You 'could' propose a devm_ version of iio_map_array_register and
then use that to ensure the ordering is correctly maintained.

> +
> +		if (IS_ERR(info->tzds[i].tzd)) {
> +			dev_err(info->sensor_device,
> +				"could not register thermal sensor: %ld\n",
> +				PTR_ERR(info->tzds[i].tzd));
> +			return PTR_ERR(info->tzds[i].tzd);
> +		}
> +	}
> +
> +	return 0;
> +}
> +
>  static int sun4i_gpadc_probe(struct platform_device *pdev)
>  {
>  	struct sun4i_gpadc_iio *info;
> @@ -646,19 +683,13 @@ static int sun4i_gpadc_probe(struct platform_device *pdev)
>  	pm_runtime_enable(&pdev->dev);
>  
>  	if (IS_ENABLED(CONFIG_THERMAL_OF)) {
> -		info->tzd = thermal_zone_of_sensor_register(info->sensor_device,
> -							    0, info,
> -							    &sun4i_ts_tz_ops);
> +		ret = sun4i_sensor_init(info);
>  		/*
>  		 * Do not fail driver probing when failing to register in
>  		 * thermal because no thermal DT node is found.
>  		 */
> -		if (IS_ERR(info->tzd) && PTR_ERR(info->tzd) != -ENODEV) {
> -			dev_err(&pdev->dev,
> -				"could not register thermal sensor: %ld\n",
> -				PTR_ERR(info->tzd));
> -			return PTR_ERR(info->tzd);
> -		}
> +		if (ret && ret != -ENODEV)
> +			return ret;
>  	}
>  
>  	ret = devm_iio_device_register(&pdev->dev, indio_dev);
> @@ -690,8 +721,6 @@ static int sun4i_gpadc_remove(struct platform_device *pdev)
>  	if (!IS_ENABLED(CONFIG_THERMAL_OF))
>  		return 0;
>  
> -	thermal_zone_of_sensor_unregister(info->sensor_device, info->tzd);
> -
>  	if (!info->no_irq)
>  		iio_map_array_unregister(indio_dev);
>  

Re: [PATCH 1/7] iio: adc: sun4i-gpadc: rework for support multiple thermal sensor

[Maxime Ripard]

[-- Attachment #1: Type: text/plain, Size: 3081 bytes --]

Hi,

On Sun, May 05, 2019 at 04:22:15PM +0100, Jonathan Cameron wrote:
> On Fri,  3 May 2019 03:28:07 -0400
> Yangtao Li <tiny.windzz@gmail.com> wrote:
>
> > For some SOCs, there are more than one thermal sensor, and there are
> > currently four sensors on the A80. So we need to do some work in order
> > to support multiple thermal sensors:
> >
> >   1) add sensor_count in gpadc_data.
> >   2) introduce sun4i_sensor_tzd in sun4i_gpadc_iio, to support multiple
> >      thermal_zone_device and distinguish between different sensors.
> >   3) modify read temperature and initialization function.
>
> This comment doesn't mention the devm change. If it had it would have
> raised immediate alarm bells.
>
> I'm also not keen on the web of pointers that this driver is steadily
> evolving.  I can't immediately see how to reduce that complexity however.

So I might be responsible for that, and looking back, this has been a
mistake.

This driver was initally put together to support a controller found in
older (A10 up to A31) Allwinner SoCs. This controller had an ADC
driver that could be operated as a touchscreen controller, and was
providing a CPU temperature sensor and a general purpose ADC.

However, we already had a driver for that controller in drivers/input
to report the CPU temperature, and the one in IIO was introduced to
support the general purpose ADC (and the CPU temperature). The long
term goal was to add the touchscreen feature as well eventually so
that we could remove the one in drivers/input. That didn't happen.

At the same time, the Allwinner hardware slowly evolved to remove the
touchscreen and ADC features, and only keep the CPU temperature
readout. It then evolved further on to support multiple temperatures
(for different clusters, the GPU, and so on).

So, today, we're in a situation where I was pushing everything into
that IIO drivers since there was similiraties between all the
generations, but the fact that we have to support so many odd cases
(DT bindings compatibility, controllers with and without ADC, etc)
that it becomes a real mess.

And that mess isn't really used by anybody, since we want to have the
touchscreen.

There's only one SoC that is supported only by that driver, which is
the A33 that only had a CPU temperature readout, and is still pretty
similar to the latest SoC from Allwinner (that is supported by this
series).

I guess, for everyone's sanity and in order to not stall this further,
it would just be better to create an hwmon driver for the A33 (and
onwards, including the H6) for the SoC that just have the temperature
readout feature. And for the older SoC, we just keep the older driver
under input/. Once the A33 is supported, we'll remove the driver in
IIO (and the related bits in drivers/mfd).

Armbian already has a driver for that they never upstreamed iirc, so
it might be a good starting point, and we would add the support for
the H6. How does that sound?

Sorry for wasting everybody's time on this.

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

[-- Attachment #2: signature.asc --]
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Re: [PATCH 1/7] iio: adc: sun4i-gpadc: rework for support multiple thermal sensor

[Icenowy Zheng]

在 2019-05-06一的 14:28 +0200，Maxime Ripard写道：
> Hi,
> 
> On Sun, May 05, 2019 at 04:22:15PM +0100, Jonathan Cameron wrote:
> > On Fri,  3 May 2019 03:28:07 -0400
> > Yangtao Li <tiny.windzz@gmail.com> wrote:
> > 
> > > For some SOCs, there are more than one thermal sensor, and there
> > > are
> > > currently four sensors on the A80. So we need to do some work in
> > > order
> > > to support multiple thermal sensors:
> > > 
> > >   1) add sensor_count in gpadc_data.
> > >   2) introduce sun4i_sensor_tzd in sun4i_gpadc_iio, to support
> > > multiple
> > >      thermal_zone_device and distinguish between different
> > > sensors.
> > >   3) modify read temperature and initialization function.
> > 
> > This comment doesn't mention the devm change. If it had it would
> > have
> > raised immediate alarm bells.
> > 
> > I'm also not keen on the web of pointers that this driver is
> > steadily
> > evolving.  I can't immediately see how to reduce that complexity
> > however.
> 
> So I might be responsible for that, and looking back, this has been a
> mistake.
> 
> This driver was initally put together to support a controller found
> in
> older (A10 up to A31) Allwinner SoCs. This controller had an ADC
> driver that could be operated as a touchscreen controller, and was
> providing a CPU temperature sensor and a general purpose ADC.
> 
> However, we already had a driver for that controller in drivers/input
> to report the CPU temperature, and the one in IIO was introduced to
> support the general purpose ADC (and the CPU temperature). The long
> term goal was to add the touchscreen feature as well eventually so
> that we could remove the one in drivers/input. That didn't happen.
> 
> At the same time, the Allwinner hardware slowly evolved to remove the
> touchscreen and ADC features, and only keep the CPU temperature
> readout. It then evolved further on to support multiple temperatures
> (for different clusters, the GPU, and so on).
> 
> So, today, we're in a situation where I was pushing everything into
> that IIO drivers since there was similiraties between all the
> generations, but the fact that we have to support so many odd cases
> (DT bindings compatibility, controllers with and without ADC, etc)
> that it becomes a real mess.
> 
> And that mess isn't really used by anybody, since we want to have the
> touchscreen.
> 
> There's only one SoC that is supported only by that driver, which is
> the A33 that only had a CPU temperature readout, and is still pretty
> similar to the latest SoC from Allwinner (that is supported by this
> series).
> 
> I guess, for everyone's sanity and in order to not stall this
> further,
> it would just be better to create an hwmon driver for the A33 (and
> onwards, including the H6) for the SoC that just have the temperature
> readout feature. And for the older SoC, we just keep the older driver
> under input/. Once the A33 is supported, we'll remove the driver in
> IIO (and the related bits in drivers/mfd).

I think a thermal driver is better.

Other SoCs' thermal sensor drivers are all thermal drivers.

> 
> Armbian already has a driver for that they never upstreamed iirc, so
> it might be a good starting point, and we would add the support for
> the H6. How does that sound?

I think the developer abandoned to upstream it because of the previous
problem ;-)

Maybe it can be taken and add A33&H6 support.

> 
> Sorry for wasting everybody's time on this.
> 
> Maxime
> 
> --
> Maxime Ripard, Bootlin
> Embedded Linux and Kernel engineering
> https://bootlin.com
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH 1/7] iio: adc: sun4i-gpadc: rework for support multiple thermal sensor

[Frank Lee]

On Tue, May 7, 2019 at 12:52 AM Icenowy Zheng <icenowy@aosc.io> wrote:
>
> 在 2019-05-06一的 14:28 +0200，Maxime Ripard写道：
> > Hi,
> >
> > On Sun, May 05, 2019 at 04:22:15PM +0100, Jonathan Cameron wrote:
> > > On Fri,  3 May 2019 03:28:07 -0400
> > > Yangtao Li <tiny.windzz@gmail.com> wrote:
> > >
> > > > For some SOCs, there are more than one thermal sensor, and there
> > > > are
> > > > currently four sensors on the A80. So we need to do some work in
> > > > order
> > > > to support multiple thermal sensors:
> > > >
> > > >   1) add sensor_count in gpadc_data.
> > > >   2) introduce sun4i_sensor_tzd in sun4i_gpadc_iio, to support
> > > > multiple
> > > >      thermal_zone_device and distinguish between different
> > > > sensors.
> > > >   3) modify read temperature and initialization function.
> > >
> > > This comment doesn't mention the devm change. If it had it would
> > > have
> > > raised immediate alarm bells.
> > >
> > > I'm also not keen on the web of pointers that this driver is
> > > steadily
> > > evolving.  I can't immediately see how to reduce that complexity
> > > however.
> >
> > So I might be responsible for that, and looking back, this has been a
> > mistake.
> >
> > This driver was initally put together to support a controller found
> > in
> > older (A10 up to A31) Allwinner SoCs. This controller had an ADC
> > driver that could be operated as a touchscreen controller, and was
> > providing a CPU temperature sensor and a general purpose ADC.
> >
> > However, we already had a driver for that controller in drivers/input
> > to report the CPU temperature, and the one in IIO was introduced to
> > support the general purpose ADC (and the CPU temperature). The long
> > term goal was to add the touchscreen feature as well eventually so
> > that we could remove the one in drivers/input. That didn't happen.
> >
> > At the same time, the Allwinner hardware slowly evolved to remove the
> > touchscreen and ADC features, and only keep the CPU temperature
> > readout. It then evolved further on to support multiple temperatures
> > (for different clusters, the GPU, and so on).
> >
> > So, today, we're in a situation where I was pushing everything into
> > that IIO drivers since there was similiraties between all the
> > generations, but the fact that we have to support so many odd cases
> > (DT bindings compatibility, controllers with and without ADC, etc)
> > that it becomes a real mess.
> >
> > And that mess isn't really used by anybody, since we want to have the
> > touchscreen.
> >
> > There's only one SoC that is supported only by that driver, which is
> > the A33 that only had a CPU temperature readout, and is still pretty
> > similar to the latest SoC from Allwinner (that is supported by this
> > series).
> >
> > I guess, for everyone's sanity and in order to not stall this
> > further,
> > it would just be better to create an hwmon driver for the A33 (and
> > onwards, including the H6) for the SoC that just have the temperature
> > readout feature. And for the older SoC, we just keep the older driver
> > under input/. Once the A33 is supported, we'll remove the driver in
> > IIO (and the related bits in drivers/mfd).

a hwmon driver or a thermal driver？

>
> I think a thermal driver is better.

This is what I hope to see a few months ago.

>
> Other SoCs' thermal sensor drivers are all thermal drivers.
>
> >
> > Armbian already has a driver for that they never upstreamed iirc, so
> > it might be a good starting point, and we would add the support for
> > the H6. How does that sound?
>
> I think the developer abandoned to upstream it because of the previous
> problem ;-)
>
> Maybe it can be taken and add A33&H6 support.

If OK, I am going to start some thermal driver work this weekend.  : )

Cheers,
Yangtao

>
> >
> > Sorry for wasting everybody's time on this.
> >
> > Maxime
> >
> > --
> > Maxime Ripard, Bootlin
> > Embedded Linux and Kernel engineering
> > https://bootlin.com
> > _______________________________________________
> > linux-arm-kernel mailing list
> > linux-arm-kernel@lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>

Re: [PATCH 1/7] iio: adc: sun4i-gpadc: rework for support multiple thermal sensor

[Ondřej Jirman]

Hi,

On Tue, May 07, 2019 at 01:08:39AM +0800, Frank Lee wrote:
> On Tue, May 7, 2019 at 12:52 AM Icenowy Zheng <icenowy@aosc.io> wrote:
> >
> > 在 2019-05-06一的 14:28 +0200，Maxime Ripard写道：
> > > Hi,
> > >
> > > On Sun, May 05, 2019 at 04:22:15PM +0100, Jonathan Cameron wrote:
> > > > On Fri,  3 May 2019 03:28:07 -0400
> > > > Yangtao Li <tiny.windzz@gmail.com> wrote:
> > > >
> > > > > For some SOCs, there are more than one thermal sensor, and there
> > > > > are
> > > > > currently four sensors on the A80. So we need to do some work in
> > > > > order
> > > > > to support multiple thermal sensors:
> > > > >
> > > > >   1) add sensor_count in gpadc_data.
> > > > >   2) introduce sun4i_sensor_tzd in sun4i_gpadc_iio, to support
> > > > > multiple
> > > > >      thermal_zone_device and distinguish between different
> > > > > sensors.
> > > > >   3) modify read temperature and initialization function.
> > > >
> > > > This comment doesn't mention the devm change. If it had it would
> > > > have
> > > > raised immediate alarm bells.
> > > >
> > > > I'm also not keen on the web of pointers that this driver is
> > > > steadily
> > > > evolving.  I can't immediately see how to reduce that complexity
> > > > however.
> > >
> > > So I might be responsible for that, and looking back, this has been a
> > > mistake.
> > >
> > > This driver was initally put together to support a controller found
> > > in
> > > older (A10 up to A31) Allwinner SoCs. This controller had an ADC
> > > driver that could be operated as a touchscreen controller, and was
> > > providing a CPU temperature sensor and a general purpose ADC.
> > >
> > > However, we already had a driver for that controller in drivers/input
> > > to report the CPU temperature, and the one in IIO was introduced to
> > > support the general purpose ADC (and the CPU temperature). The long
> > > term goal was to add the touchscreen feature as well eventually so
> > > that we could remove the one in drivers/input. That didn't happen.
> > >
> > > At the same time, the Allwinner hardware slowly evolved to remove the
> > > touchscreen and ADC features, and only keep the CPU temperature
> > > readout. It then evolved further on to support multiple temperatures
> > > (for different clusters, the GPU, and so on).
> > >
> > > So, today, we're in a situation where I was pushing everything into
> > > that IIO drivers since there was similiraties between all the
> > > generations, but the fact that we have to support so many odd cases
> > > (DT bindings compatibility, controllers with and without ADC, etc)
> > > that it becomes a real mess.
> > >
> > > And that mess isn't really used by anybody, since we want to have the
> > > touchscreen.
> > >
> > > There's only one SoC that is supported only by that driver, which is
> > > the A33 that only had a CPU temperature readout, and is still pretty
> > > similar to the latest SoC from Allwinner (that is supported by this
> > > series).
> > >
> > > I guess, for everyone's sanity and in order to not stall this
> > > further,
> > > it would just be better to create an hwmon driver for the A33 (and
> > > onwards, including the H6) for the SoC that just have the temperature
> > > readout feature. And for the older SoC, we just keep the older driver
> > > under input/. Once the A33 is supported, we'll remove the driver in
> > > IIO (and the related bits in drivers/mfd).
> 
> a hwmon driver or a thermal driver？
> 
> >
> > I think a thermal driver is better.
> 
> This is what I hope to see a few months ago.
> 
> >
> > Other SoCs' thermal sensor drivers are all thermal drivers.
> >
> > >
> > > Armbian already has a driver for that they never upstreamed iirc, so
> > > it might be a good starting point, and we would add the support for
> > > the H6. How does that sound?
> >
> > I think the developer abandoned to upstream it because of the previous
> > problem ;-)
> >
> > Maybe it can be taken and add A33&H6 support.
> 
> If OK, I am going to start some thermal driver work this weekend.  : )

There are plenty of thermal drivers flying around, with varying levels
of support for various SoCs:

- H3/H5: https://megous.com/git/linux/commit/?h=ths-5.1&id=b8e20c5da7a00b3a3fa1b274fc8d5bea95872b0a
- A83T: https://megous.com/git/linux/commit/?h=ths-5.1&id=796dff9a946fd475cc1e4bb948a723ea841c640c
- H6: https://megous.com/git/linux/commit/?h=opi3-5.1&id=aeab762c19b4aa228a295258c9d6b2e1f143bf86

For H3/H5 Icenowy also tried to upstream some variant of my THS driver, with
better SID/calibration data reading support.

I'd suggest starting with the H6 driver above (as that implements the
calibration data readout correctly), and make it so that it can support multiple
SoCs.

regards,
	o.

> Cheers,
> Yangtao
> 
> >
> > >
> > > Sorry for wasting everybody's time on this.
> > >
> > > Maxime
> > >
> > > --
> > > Maxime Ripard, Bootlin
> > > Embedded Linux and Kernel engineering
> > > https://bootlin.com
> > > _______________________________________________
> > > linux-arm-kernel mailing list
> > > linux-arm-kernel@lists.infradead.org
> > > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> >
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH 1/7] iio: adc: sun4i-gpadc: rework for support multiple thermal sensor

[Maxime Ripard]

[-- Attachment #1: Type: text/plain, Size: 5231 bytes --]

On Mon, May 06, 2019 at 07:55:25PM +0200, Ondřej Jirman wrote:
> On Tue, May 07, 2019 at 01:08:39AM +0800, Frank Lee wrote:
> > On Tue, May 7, 2019 at 12:52 AM Icenowy Zheng <icenowy@aosc.io> wrote:
> > >
> > > 在 2019-05-06一的 14:28 +0200，Maxime Ripard写道：
> > > > Hi,
> > > >
> > > > On Sun, May 05, 2019 at 04:22:15PM +0100, Jonathan Cameron wrote:
> > > > > On Fri,  3 May 2019 03:28:07 -0400
> > > > > Yangtao Li <tiny.windzz@gmail.com> wrote:
> > > > >
> > > > > > For some SOCs, there are more than one thermal sensor, and there
> > > > > > are
> > > > > > currently four sensors on the A80. So we need to do some work in
> > > > > > order
> > > > > > to support multiple thermal sensors:
> > > > > >
> > > > > >   1) add sensor_count in gpadc_data.
> > > > > >   2) introduce sun4i_sensor_tzd in sun4i_gpadc_iio, to support
> > > > > > multiple
> > > > > >      thermal_zone_device and distinguish between different
> > > > > > sensors.
> > > > > >   3) modify read temperature and initialization function.
> > > > >
> > > > > This comment doesn't mention the devm change. If it had it would
> > > > > have
> > > > > raised immediate alarm bells.
> > > > >
> > > > > I'm also not keen on the web of pointers that this driver is
> > > > > steadily
> > > > > evolving.  I can't immediately see how to reduce that complexity
> > > > > however.
> > > >
> > > > So I might be responsible for that, and looking back, this has been a
> > > > mistake.
> > > >
> > > > This driver was initally put together to support a controller found
> > > > in
> > > > older (A10 up to A31) Allwinner SoCs. This controller had an ADC
> > > > driver that could be operated as a touchscreen controller, and was
> > > > providing a CPU temperature sensor and a general purpose ADC.
> > > >
> > > > However, we already had a driver for that controller in drivers/input
> > > > to report the CPU temperature, and the one in IIO was introduced to
> > > > support the general purpose ADC (and the CPU temperature). The long
> > > > term goal was to add the touchscreen feature as well eventually so
> > > > that we could remove the one in drivers/input. That didn't happen.
> > > >
> > > > At the same time, the Allwinner hardware slowly evolved to remove the
> > > > touchscreen and ADC features, and only keep the CPU temperature
> > > > readout. It then evolved further on to support multiple temperatures
> > > > (for different clusters, the GPU, and so on).
> > > >
> > > > So, today, we're in a situation where I was pushing everything into
> > > > that IIO drivers since there was similiraties between all the
> > > > generations, but the fact that we have to support so many odd cases
> > > > (DT bindings compatibility, controllers with and without ADC, etc)
> > > > that it becomes a real mess.
> > > >
> > > > And that mess isn't really used by anybody, since we want to have the
> > > > touchscreen.
> > > >
> > > > There's only one SoC that is supported only by that driver, which is
> > > > the A33 that only had a CPU temperature readout, and is still pretty
> > > > similar to the latest SoC from Allwinner (that is supported by this
> > > > series).
> > > >
> > > > I guess, for everyone's sanity and in order to not stall this
> > > > further,
> > > > it would just be better to create an hwmon driver for the A33 (and
> > > > onwards, including the H6) for the SoC that just have the temperature
> > > > readout feature. And for the older SoC, we just keep the older driver
> > > > under input/. Once the A33 is supported, we'll remove the driver in
> > > > IIO (and the related bits in drivers/mfd).
> >
> > a hwmon driver or a thermal driver？
> >
> > >
> > > I think a thermal driver is better.
> >
> > This is what I hope to see a few months ago.
> >
> > >
> > > Other SoCs' thermal sensor drivers are all thermal drivers.
> > >
> > > >
> > > > Armbian already has a driver for that they never upstreamed iirc, so
> > > > it might be a good starting point, and we would add the support for
> > > > the H6. How does that sound?
> > >
> > > I think the developer abandoned to upstream it because of the previous
> > > problem ;-)
> > >
> > > Maybe it can be taken and add A33&H6 support.
> >
> > If OK, I am going to start some thermal driver work this weekend.  : )
>
> There are plenty of thermal drivers flying around, with varying levels
> of support for various SoCs:
>
> - H3/H5: https://megous.com/git/linux/commit/?h=ths-5.1&id=b8e20c5da7a00b3a3fa1b274fc8d5bea95872b0a
> - A83T: https://megous.com/git/linux/commit/?h=ths-5.1&id=796dff9a946fd475cc1e4bb948a723ea841c640c
> - H6: https://megous.com/git/linux/commit/?h=opi3-5.1&id=aeab762c19b4aa228a295258c9d6b2e1f143bf86
>
> For H3/H5 Icenowy also tried to upstream some variant of my THS driver, with
> better SID/calibration data reading support.
>
> I'd suggest starting with the H6 driver above (as that implements the
> calibration data readout correctly), and make it so that it can support multiple
> SoCs.

Yeah, that seems like a good plan

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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[-- Type: application/pgp-signature, Size: 228 bytes --]

[PATCH 2/7] iio: adc: sun4i-gpadc: introduce temp_data in gpadc_data

[Yangtao Li]

For some SOCs, the temperature data register start address may be
different, so introduce temp_data in gpadc_data.

Also modify read temperature to support multiple sensor.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
---
 drivers/iio/adc/sun4i-gpadc-iio.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c
index 844fd52bd22f..b41ec0d5964d 100644
--- a/drivers/iio/adc/sun4i-gpadc-iio.c
+++ b/drivers/iio/adc/sun4i-gpadc-iio.c
@@ -57,6 +57,7 @@ struct gpadc_data {
 	unsigned int	(*adc_chan_select)(unsigned int chan);
 	unsigned int	adc_chan_mask;
 	unsigned int    sensor_count;
+	unsigned int    temp_data_base;
 };
 
 static const struct gpadc_data sun4i_gpadc_data = {
@@ -67,6 +68,7 @@ static const struct gpadc_data sun4i_gpadc_data = {
 	.adc_chan_select = &sun4i_gpadc_chan_select,
 	.adc_chan_mask = SUN4I_GPADC_CTRL1_ADC_CHAN_MASK,
 	.sensor_count = 1,
+	.temp_data_base = SUN4I_GPADC_TEMP_DATA,
 };
 
 static const struct gpadc_data sun5i_gpadc_data = {
@@ -77,6 +79,7 @@ static const struct gpadc_data sun5i_gpadc_data = {
 	.adc_chan_select = &sun4i_gpadc_chan_select,
 	.adc_chan_mask = SUN4I_GPADC_CTRL1_ADC_CHAN_MASK,
 	.sensor_count = 1,
+	.temp_data_base = SUN4I_GPADC_TEMP_DATA,
 };
 
 static const struct gpadc_data sun6i_gpadc_data = {
@@ -87,6 +90,7 @@ static const struct gpadc_data sun6i_gpadc_data = {
 	.adc_chan_select = &sun6i_gpadc_chan_select,
 	.adc_chan_mask = SUN6I_GPADC_CTRL1_ADC_CHAN_MASK,
 	.sensor_count = 1,
+	.temp_data_base = SUN4I_GPADC_TEMP_DATA,
 };
 
 static const struct gpadc_data sun8i_a33_gpadc_data = {
@@ -94,6 +98,7 @@ static const struct gpadc_data sun8i_a33_gpadc_data = {
 	.temp_scale = 162,
 	.tp_mode_en = SUN8I_GPADC_CTRL1_CHOP_TEMP_EN,
 	.sensor_count = 1,
+	.temp_data_base = SUN4I_GPADC_TEMP_DATA,
 };
 
 struct sun4i_sensor_tzd {
@@ -291,7 +296,8 @@ static int sun4i_gpadc_temp_read(struct iio_dev *indio_dev, int *val,
 	if (info->no_irq) {
 		pm_runtime_get_sync(indio_dev->dev.parent);
 
-		regmap_read(info->regmap, SUN4I_GPADC_TEMP_DATA, val);
+		regmap_read(info->regmap, info->data->temp_data_base +
+			    0x4 * sensor, val);
 
 		pm_runtime_mark_last_busy(indio_dev->dev.parent);
 		pm_runtime_put_autosuspend(indio_dev->dev.parent);
-- 
2.17.1

[PATCH 3/7] iio: adc: sun4i-gpadc: introduce gpadc_enable and gpadc_disable in gpadc_data

[Yangtao Li]

Different sensors may have different enable and disable functions, so
introduce enable and disable in gpadc_data to support soc specific
function.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
---
 drivers/iio/adc/sun4i-gpadc-iio.c | 37 ++++++++++++++++++++++++++-----
 1 file changed, 31 insertions(+), 6 deletions(-)

diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c
index b41ec0d5964d..de6b8556a549 100644
--- a/drivers/iio/adc/sun4i-gpadc-iio.c
+++ b/drivers/iio/adc/sun4i-gpadc-iio.c
@@ -49,6 +49,8 @@ static unsigned int sun6i_gpadc_chan_select(unsigned int chan)
 	return SUN6I_GPADC_CTRL1_ADC_CHAN_SELECT(chan);
 }
 
+struct sun4i_gpadc_iio;
+
 struct gpadc_data {
 	int		temp_offset;
 	int		temp_scale;
@@ -56,10 +58,15 @@ struct gpadc_data {
 	unsigned int	tp_adc_select;
 	unsigned int	(*adc_chan_select)(unsigned int chan);
 	unsigned int	adc_chan_mask;
+	int             (*gpadc_enable)(struct sun4i_gpadc_iio *info);
+	int             (*gpadc_disable)(struct sun4i_gpadc_iio *info);
 	unsigned int    sensor_count;
 	unsigned int    temp_data_base;
 };
 
+static int sun4i_gpadc_disable(struct sun4i_gpadc_iio *info);
+static int sun4i_gpadc_enable(struct sun4i_gpadc_iio *info);
+
 static const struct gpadc_data sun4i_gpadc_data = {
 	.temp_offset = -1932,
 	.temp_scale = 133,
@@ -67,6 +74,8 @@ static const struct gpadc_data sun4i_gpadc_data = {
 	.tp_adc_select = SUN4I_GPADC_CTRL1_TP_ADC_SELECT,
 	.adc_chan_select = &sun4i_gpadc_chan_select,
 	.adc_chan_mask = SUN4I_GPADC_CTRL1_ADC_CHAN_MASK,
+	.gpadc_enable = sun4i_gpadc_enable,
+	.gpadc_disable = sun4i_gpadc_disable,
 	.sensor_count = 1,
 	.temp_data_base = SUN4I_GPADC_TEMP_DATA,
 };
@@ -78,6 +87,8 @@ static const struct gpadc_data sun5i_gpadc_data = {
 	.tp_adc_select = SUN4I_GPADC_CTRL1_TP_ADC_SELECT,
 	.adc_chan_select = &sun4i_gpadc_chan_select,
 	.adc_chan_mask = SUN4I_GPADC_CTRL1_ADC_CHAN_MASK,
+	.gpadc_enable = sun4i_gpadc_enable,
+	.gpadc_disable = sun4i_gpadc_disable,
 	.sensor_count = 1,
 	.temp_data_base = SUN4I_GPADC_TEMP_DATA,
 };
@@ -89,6 +100,8 @@ static const struct gpadc_data sun6i_gpadc_data = {
 	.tp_adc_select = SUN6I_GPADC_CTRL1_TP_ADC_SELECT,
 	.adc_chan_select = &sun6i_gpadc_chan_select,
 	.adc_chan_mask = SUN6I_GPADC_CTRL1_ADC_CHAN_MASK,
+	.gpadc_enable = sun4i_gpadc_enable,
+	.gpadc_disable = sun4i_gpadc_disable,
 	.sensor_count = 1,
 	.temp_data_base = SUN4I_GPADC_TEMP_DATA,
 };
@@ -97,6 +110,8 @@ static const struct gpadc_data sun8i_a33_gpadc_data = {
 	.temp_offset = -1662,
 	.temp_scale = 162,
 	.tp_mode_en = SUN8I_GPADC_CTRL1_CHOP_TEMP_EN,
+	.gpadc_enable = sun4i_gpadc_enable,
+	.gpadc_disable = sun4i_gpadc_disable,
 	.sensor_count = 1,
 	.temp_data_base = SUN4I_GPADC_TEMP_DATA,
 };
@@ -402,10 +417,8 @@ static irqreturn_t sun4i_gpadc_fifo_data_irq_handler(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
-static int sun4i_gpadc_runtime_suspend(struct device *dev)
+static int sun4i_gpadc_disable(struct sun4i_gpadc_iio *info)
 {
-	struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev));
-
 	/* Disable the ADC on IP */
 	regmap_write(info->regmap, SUN4I_GPADC_CTRL1, 0);
 	/* Disable temperature sensor on IP */
@@ -414,10 +427,8 @@ static int sun4i_gpadc_runtime_suspend(struct device *dev)
 	return 0;
 }
 
-static int sun4i_gpadc_runtime_resume(struct device *dev)
+static int sun4i_gpadc_enable(struct sun4i_gpadc_iio *info)
 {
-	struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev));
-
 	/* clkin = 6MHz */
 	regmap_write(info->regmap, SUN4I_GPADC_CTRL0,
 		     SUN4I_GPADC_CTRL0_ADC_CLK_DIVIDER(2) |
@@ -435,6 +446,20 @@ static int sun4i_gpadc_runtime_resume(struct device *dev)
 	return 0;
 }
 
+static int sun4i_gpadc_runtime_suspend(struct device *dev)
+{
+	struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev));
+
+	return info->data->gpadc_disable(info);
+}
+
+static int sun4i_gpadc_runtime_resume(struct device *dev)
+{
+	struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev));
+
+	return info->data->gpadc_enable(info);
+}
+
 static int sun4i_gpadc_get_temp(void *data, int *temp)
 {
 	struct sun4i_sensor_tzd *tzd = data;
-- 
2.17.1

[PATCH 4/7] iio: adc: sun4i-gpadc-iio: support clocks and reset

[Yangtao Li]

H6 has bus clock and a reset, so introduce something in
gpadc_data/sun4i_gpadc_iio and adds the process of the
clocks and resets.

This is pre-work for supprt it.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
---
 drivers/iio/adc/sun4i-gpadc-iio.c | 32 +++++++++++++++++++++++++++++--
 1 file changed, 30 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c
index de6b8556a549..f24eb76d65c0 100644
--- a/drivers/iio/adc/sun4i-gpadc-iio.c
+++ b/drivers/iio/adc/sun4i-gpadc-iio.c
@@ -22,6 +22,7 @@
  * shutdown for not being used.
  */
 
+#include <linux/clk.h>
 #include <linux/completion.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
@@ -31,6 +32,7 @@
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/regmap.h>
+#include <linux/reset.h>
 #include <linux/thermal.h>
 #include <linux/delay.h>
 
@@ -52,6 +54,8 @@ static unsigned int sun6i_gpadc_chan_select(unsigned int chan)
 struct sun4i_gpadc_iio;
 
 struct gpadc_data {
+	bool            has_bus_clk;
+	bool            has_bus_rst;
 	int		temp_offset;
 	int		temp_scale;
 	unsigned int	tp_mode_en;
@@ -140,6 +144,8 @@ struct sun4i_gpadc_iio {
 	struct mutex			mutex;
 	struct sun4i_sensor_tzd         tzds[MAX_SENSOR_COUNT];
 	struct device			*sensor_device;
+	struct clk                      *bus_clk;
+	struct reset_control            *reset;
 };
 
 #define SUN4I_GPADC_ADC_CHANNEL(_channel, _name) {		\
@@ -564,14 +570,36 @@ static int sun4i_gpadc_probe_dt(struct platform_device *pdev,
 	if (IS_ERR(base))
 		return PTR_ERR(base);
 
-	info->regmap = devm_regmap_init_mmio(&pdev->dev, base,
-					     &sun4i_gpadc_regmap_config);
+	if (info->data->has_bus_clk)
+		info->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "bus",
+							 base,
+						&sun4i_gpadc_regmap_config);
+	else
+		info->regmap = devm_regmap_init_mmio(&pdev->dev, base,
+						&sun4i_gpadc_regmap_config);
+
 	if (IS_ERR(info->regmap)) {
 		ret = PTR_ERR(info->regmap);
 		dev_err(&pdev->dev, "failed to init regmap: %d\n", ret);
 		return ret;
 	}
 
+	if (info->data->has_bus_rst) {
+		info->reset = devm_reset_control_get(&pdev->dev, "bus");
+		if (IS_ERR(info->reset)) {
+			ret = PTR_ERR(info->reset);
+			return ret;
+		}
+	}
+
+	if (info->data->has_bus_clk) {
+		info->bus_clk = devm_clk_get(&pdev->dev, "bus");
+		if (IS_ERR(info->bus_clk)) {
+			ret = PTR_ERR(info->bus_clk);
+			return ret;
+		}
+	}
+
 	if (IS_ENABLED(CONFIG_THERMAL_OF))
 		info->sensor_device = &pdev->dev;
 
-- 
2.17.1

[PATCH 5/7] dt-bindings: mfd: Add H6 GPADC binding

[Yangtao Li]

This patch adds documentation for the H6 GPADC binding.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
---
 .../devicetree/bindings/mfd/sun4i-gpadc.txt   | 27 +++++++++++++++++--
 1 file changed, 25 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/mfd/sun4i-gpadc.txt b/Documentation/devicetree/bindings/mfd/sun4i-gpadc.txt
index 86dd8191b04c..eeaf27eb8abd 100644
--- a/Documentation/devicetree/bindings/mfd/sun4i-gpadc.txt
+++ b/Documentation/devicetree/bindings/mfd/sun4i-gpadc.txt
@@ -5,11 +5,22 @@ and sometimes as a touchscreen controller.
 
 Required properties:
   - compatible: "allwinner,sun8i-a33-ths",
+		"allwinner,sun50i-h6-ths",
   - reg: mmio address range of the chip,
-  - #thermal-sensor-cells: shall be 0,
+  - #thermal-sensor-cells: shall be 0 for sun8i-a33-ths,
+			   shall be 1 for sun50i-h6-ths,
   - #io-channel-cells: shall be 0,
 
-Example:
+Optional properties:
+  - clocks: Must contain an entry for each entry in clock-names.
+	    See common clock-bindings.txt for details.
+  - clock-names: A list of clock names. For sun50i-h6-ths, it must contain
+		 "bus".
+  - resets: Must contain an entry for each entry in reset-names.
+	    See ../reset/reset.txt for details.
+  - reset-names: For sun50i-h6-ths, it must contain "bus".
+
+Example1:
 	ths: ths@1c25000 {
 		compatible = "allwinner,sun8i-a33-ths";
 		reg = <0x01c25000 0x100>;
@@ -17,6 +28,18 @@ Example:
 		#io-channel-cells = <0>;
 	};
 
+Example2:
+	ths: ths@1c25000 {
+		compatible = "allwinner,sun50i-h6-ths";
+		reg = <0x05070400 0x100>;
+		clocks = <&ccu CLK_BUS_THS>;
+		clock-names = "bus";
+		resets = <&ccu RST_BUS_THS>;
+		reset-names = "bus";
+		#thermal-sensor-cells = <1>;
+		#io-channel-cells = <0>;
+       };
+
 sun4i, sun5i and sun6i SoCs are also supported via the older binding:
 
 sun4i resistive touchscreen controller
-- 
2.17.1

Re: [PATCH 5/7] dt-bindings: mfd: Add H6 GPADC binding

[Lee Jones]

On Fri, 03 May 2019, Yangtao Li wrote:

> This patch adds documentation for the H6 GPADC binding.
> 
> Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
> ---
>  .../devicetree/bindings/mfd/sun4i-gpadc.txt   | 27 +++++++++++++++++--
>  1 file changed, 25 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/mfd/sun4i-gpadc.txt b/Documentation/devicetree/bindings/mfd/sun4i-gpadc.txt
> index 86dd8191b04c..eeaf27eb8abd 100644
> --- a/Documentation/devicetree/bindings/mfd/sun4i-gpadc.txt
> +++ b/Documentation/devicetree/bindings/mfd/sun4i-gpadc.txt
> @@ -5,11 +5,22 @@ and sometimes as a touchscreen controller.
>  
>  Required properties:
>    - compatible: "allwinner,sun8i-a33-ths",
> +		"allwinner,sun50i-h6-ths",
>    - reg: mmio address range of the chip,
> -  - #thermal-sensor-cells: shall be 0,
> +  - #thermal-sensor-cells: shall be 0 for sun8i-a33-ths,
> +			   shall be 1 for sun50i-h6-ths,
>    - #io-channel-cells: shall be 0,
>  
> -Example:
> +Optional properties:
> +  - clocks: Must contain an entry for each entry in clock-names.
> +	    See common clock-bindings.txt for details.

Nit: This should be a relative path, like the reset.txt below.

> +  - clock-names: A list of clock names. For sun50i-h6-ths, it must contain
> +		 "bus".
> +  - resets: Must contain an entry for each entry in reset-names.
> +	    See ../reset/reset.txt for details.
> +  - reset-names: For sun50i-h6-ths, it must contain "bus".
> +
> +Example1:
>  	ths: ths@1c25000 {
>  		compatible = "allwinner,sun8i-a33-ths";
>  		reg = <0x01c25000 0x100>;
> @@ -17,6 +28,18 @@ Example:
>  		#io-channel-cells = <0>;
>  	};
>  
> +Example2:
> +	ths: ths@1c25000 {
> +		compatible = "allwinner,sun50i-h6-ths";
> +		reg = <0x05070400 0x100>;
> +		clocks = <&ccu CLK_BUS_THS>;
> +		clock-names = "bus";
> +		resets = <&ccu RST_BUS_THS>;
> +		reset-names = "bus";
> +		#thermal-sensor-cells = <1>;
> +		#io-channel-cells = <0>;
> +       };
> +
>  sun4i, sun5i and sun6i SoCs are also supported via the older binding:
>  
>  sun4i resistive touchscreen controller

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

[PATCH 6/7] iio: adc: sun4i-gpadc-iio: add support for H6 thermal sensor

[Yangtao Li]

This patch adds support for the H6 ths sensor.

TODO: calibrate thermal sensor by using information from sid.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
---
 drivers/iio/adc/sun4i-gpadc-iio.c | 65 +++++++++++++++++++++++++++++++
 include/linux/mfd/sun4i-gpadc.h   |  9 +++++
 2 files changed, 74 insertions(+)

diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c
index f24eb76d65c0..9b6fc592f54c 100644
--- a/drivers/iio/adc/sun4i-gpadc-iio.c
+++ b/drivers/iio/adc/sun4i-gpadc-iio.c
@@ -120,6 +120,20 @@ static const struct gpadc_data sun8i_a33_gpadc_data = {
 	.temp_data_base = SUN4I_GPADC_TEMP_DATA,
 };
 
+static int sun50i_gpadc_disable(struct sun4i_gpadc_iio *info);
+static int sun50i_gpadc_enable(struct sun4i_gpadc_iio *info);
+
+static const struct gpadc_data sun50i_h6_gpadc_data = {
+	.temp_offset = -2809,
+	.temp_scale = -67,
+	.has_bus_clk = true,
+	.has_bus_rst = true,
+	.gpadc_enable = sun50i_gpadc_enable,
+	.gpadc_disable = sun50i_gpadc_disable,
+	.sensor_count = 2,
+	.temp_data_base = SUN50I_H6_GPADC_TEMP_DATA,
+};
+
 struct sun4i_sensor_tzd {
 	struct sun4i_gpadc_iio          *info;
 	struct thermal_zone_device      *tzd;
@@ -452,6 +466,53 @@ static int sun4i_gpadc_enable(struct sun4i_gpadc_iio *info)
 	return 0;
 }
 
+static int sun50i_gpadc_enable(struct sun4i_gpadc_iio *info)
+{
+	int ret, val;
+
+	ret = reset_control_deassert(info->reset);
+	if (ret)
+		return ret;
+
+	ret = clk_prepare_enable(info->bus_clk);
+	if (ret)
+		goto assert_reset;
+
+	/*
+	 * clkin = 24MHz
+	 * T acquire = clkin / (SUN50I_GPADC_CTRL0_T_ACQ + 1)
+	 *           = 20us
+	 */
+	regmap_write(info->regmap, SUN4I_GPADC_CTRL0,
+		     SUN50I_GPADC_CTRL0_T_ACQ(479));
+	/* average over 4 samples */
+	regmap_write(info->regmap, SUN50I_H6_GPADC_CTRL3,
+		     SUN4I_GPADC_CTRL3_FILTER_EN |
+		     SUN4I_GPADC_CTRL3_FILTER_TYPE(1));
+	/* period = (SUN50I_GPADC_TPR_TEMP_PERIOD + 1) * 4096 / clkin; ~10ms */
+	regmap_write(info->regmap, SUN50I_GPADC_TPR,
+		     SUN50I_GPADC_TPR_TEMP_PERIOD(58));
+	/* TODO: calibrate ths */
+	/* enable sensor */
+	val = GENMASK(info->data->sensor_count - 1, 0);
+	regmap_write(info->regmap, SUN4I_GPADC_CTRL1, val);
+
+	return 0;
+
+assert_reset:
+	reset_control_assert(info->reset);
+
+	return ret;
+}
+
+static int sun50i_gpadc_disable(struct sun4i_gpadc_iio *info)
+{
+	clk_disable_unprepare(info->bus_clk);
+	reset_control_assert(info->reset);
+
+	return 0;
+}
+
 static int sun4i_gpadc_runtime_suspend(struct device *dev)
 {
 	struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev));
@@ -546,6 +607,10 @@ static const struct of_device_id sun4i_gpadc_of_id[] = {
 		.compatible = "allwinner,sun8i-a33-ths",
 		.data = &sun8i_a33_gpadc_data,
 	},
+	{
+		.compatible = "allwinner,sun50i-h6-ths",
+		.data = &sun50i_h6_gpadc_data,
+	},
 	{ /* sentinel */ }
 };
 
diff --git a/include/linux/mfd/sun4i-gpadc.h b/include/linux/mfd/sun4i-gpadc.h
index 139872c2e0fe..f505013e9c0d 100644
--- a/include/linux/mfd/sun4i-gpadc.h
+++ b/include/linux/mfd/sun4i-gpadc.h
@@ -19,6 +19,9 @@
 #define SUN4I_GPADC_CTRL0_FS_DIV(x)			((GENMASK(3, 0) & (x)) << 16)
 #define SUN4I_GPADC_CTRL0_T_ACQ(x)			(GENMASK(15, 0) & (x))
 
+/* TP_CTRL0 bits for sun50i SOCs */
+#define SUN50I_GPADC_CTRL0_T_ACQ(x)			((GENMASK(15, 0) & (x)) << 16)
+
 #define SUN4I_GPADC_CTRL1				0x04
 
 #define SUN4I_GPADC_CTRL1_STYLUS_UP_DEBOUNCE(x)		((GENMASK(7, 0) & (x)) << 12)
@@ -49,6 +52,9 @@
 #define SUN4I_GPADC_CTRL2_PRE_MEA_EN			BIT(24)
 #define SUN4I_GPADC_CTRL2_PRE_MEA_THRE_CNT(x)		(GENMASK(23, 0) & (x))
 
+#define SUN50I_GPADC_TPR				0x08
+#define SUN50I_GPADC_TPR_TEMP_PERIOD(x)			((GENMASK(19, 0) & (x)) << 12)
+
 #define SUN4I_GPADC_CTRL3				0x0c
 
 #define SUN4I_GPADC_CTRL3_FILTER_EN			BIT(2)
@@ -84,6 +90,9 @@
 #define SUN4I_GPADC_TEMP_DATA				0x20
 #define SUN4I_GPADC_DATA				0x24
 
+#define SUN50I_H6_GPADC_CTRL3				0x30
+#define SUN50I_H6_GPADC_TEMP_DATA			0xc0
+
 #define SUN4I_GPADC_IRQ_FIFO_DATA			0
 #define SUN4I_GPADC_IRQ_TEMP_DATA			1
 
-- 
2.17.1

Re: [PATCH 6/7] iio: adc: sun4i-gpadc-iio: add support for H6 thermal sensor

[Jonathan Cameron]

On Fri,  3 May 2019 03:28:12 -0400
Yangtao Li <tiny.windzz@gmail.com> wrote:

> This patch adds support for the H6 ths sensor.
> 
> TODO: calibrate thermal sensor by using information from sid.
> 
> Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
This and the patches before it that I haven't comment on look fine to me.

thanks,

Jonathan
> ---
>  drivers/iio/adc/sun4i-gpadc-iio.c | 65 +++++++++++++++++++++++++++++++
>  include/linux/mfd/sun4i-gpadc.h   |  9 +++++
>  2 files changed, 74 insertions(+)
> 
> diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c
> index f24eb76d65c0..9b6fc592f54c 100644
> --- a/drivers/iio/adc/sun4i-gpadc-iio.c
> +++ b/drivers/iio/adc/sun4i-gpadc-iio.c
> @@ -120,6 +120,20 @@ static const struct gpadc_data sun8i_a33_gpadc_data = {
>  	.temp_data_base = SUN4I_GPADC_TEMP_DATA,
>  };
>  
> +static int sun50i_gpadc_disable(struct sun4i_gpadc_iio *info);
> +static int sun50i_gpadc_enable(struct sun4i_gpadc_iio *info);
> +
> +static const struct gpadc_data sun50i_h6_gpadc_data = {
> +	.temp_offset = -2809,
> +	.temp_scale = -67,
> +	.has_bus_clk = true,
> +	.has_bus_rst = true,
> +	.gpadc_enable = sun50i_gpadc_enable,
> +	.gpadc_disable = sun50i_gpadc_disable,
> +	.sensor_count = 2,
> +	.temp_data_base = SUN50I_H6_GPADC_TEMP_DATA,
> +};
> +
>  struct sun4i_sensor_tzd {
>  	struct sun4i_gpadc_iio          *info;
>  	struct thermal_zone_device      *tzd;
> @@ -452,6 +466,53 @@ static int sun4i_gpadc_enable(struct sun4i_gpadc_iio *info)
>  	return 0;
>  }
>  
> +static int sun50i_gpadc_enable(struct sun4i_gpadc_iio *info)
> +{
> +	int ret, val;
> +
> +	ret = reset_control_deassert(info->reset);
> +	if (ret)
> +		return ret;
> +
> +	ret = clk_prepare_enable(info->bus_clk);
> +	if (ret)
> +		goto assert_reset;
> +
> +	/*
> +	 * clkin = 24MHz
> +	 * T acquire = clkin / (SUN50I_GPADC_CTRL0_T_ACQ + 1)
> +	 *           = 20us
> +	 */
> +	regmap_write(info->regmap, SUN4I_GPADC_CTRL0,
> +		     SUN50I_GPADC_CTRL0_T_ACQ(479));
> +	/* average over 4 samples */
> +	regmap_write(info->regmap, SUN50I_H6_GPADC_CTRL3,
> +		     SUN4I_GPADC_CTRL3_FILTER_EN |
> +		     SUN4I_GPADC_CTRL3_FILTER_TYPE(1));
> +	/* period = (SUN50I_GPADC_TPR_TEMP_PERIOD + 1) * 4096 / clkin; ~10ms */
> +	regmap_write(info->regmap, SUN50I_GPADC_TPR,
> +		     SUN50I_GPADC_TPR_TEMP_PERIOD(58));
> +	/* TODO: calibrate ths */
> +	/* enable sensor */
> +	val = GENMASK(info->data->sensor_count - 1, 0);
> +	regmap_write(info->regmap, SUN4I_GPADC_CTRL1, val);
> +
> +	return 0;
> +
> +assert_reset:
> +	reset_control_assert(info->reset);
> +
> +	return ret;
> +}
> +
> +static int sun50i_gpadc_disable(struct sun4i_gpadc_iio *info)
> +{
> +	clk_disable_unprepare(info->bus_clk);
> +	reset_control_assert(info->reset);
> +
> +	return 0;
> +}
> +
>  static int sun4i_gpadc_runtime_suspend(struct device *dev)
>  {
>  	struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev));
> @@ -546,6 +607,10 @@ static const struct of_device_id sun4i_gpadc_of_id[] = {
>  		.compatible = "allwinner,sun8i-a33-ths",
>  		.data = &sun8i_a33_gpadc_data,
>  	},
> +	{
> +		.compatible = "allwinner,sun50i-h6-ths",
> +		.data = &sun50i_h6_gpadc_data,
> +	},
>  	{ /* sentinel */ }
>  };
>  
> diff --git a/include/linux/mfd/sun4i-gpadc.h b/include/linux/mfd/sun4i-gpadc.h
> index 139872c2e0fe..f505013e9c0d 100644
> --- a/include/linux/mfd/sun4i-gpadc.h
> +++ b/include/linux/mfd/sun4i-gpadc.h
> @@ -19,6 +19,9 @@
>  #define SUN4I_GPADC_CTRL0_FS_DIV(x)			((GENMASK(3, 0) & (x)) << 16)
>  #define SUN4I_GPADC_CTRL0_T_ACQ(x)			(GENMASK(15, 0) & (x))
>  
> +/* TP_CTRL0 bits for sun50i SOCs */
> +#define SUN50I_GPADC_CTRL0_T_ACQ(x)			((GENMASK(15, 0) & (x)) << 16)
> +
>  #define SUN4I_GPADC_CTRL1				0x04
>  
>  #define SUN4I_GPADC_CTRL1_STYLUS_UP_DEBOUNCE(x)		((GENMASK(7, 0) & (x)) << 12)
> @@ -49,6 +52,9 @@
>  #define SUN4I_GPADC_CTRL2_PRE_MEA_EN			BIT(24)
>  #define SUN4I_GPADC_CTRL2_PRE_MEA_THRE_CNT(x)		(GENMASK(23, 0) & (x))
>  
> +#define SUN50I_GPADC_TPR				0x08
> +#define SUN50I_GPADC_TPR_TEMP_PERIOD(x)			((GENMASK(19, 0) & (x)) << 12)
> +
>  #define SUN4I_GPADC_CTRL3				0x0c
>  
>  #define SUN4I_GPADC_CTRL3_FILTER_EN			BIT(2)
> @@ -84,6 +90,9 @@
>  #define SUN4I_GPADC_TEMP_DATA				0x20
>  #define SUN4I_GPADC_DATA				0x24
>  
> +#define SUN50I_H6_GPADC_CTRL3				0x30
> +#define SUN50I_H6_GPADC_TEMP_DATA			0xc0
> +
>  #define SUN4I_GPADC_IRQ_FIFO_DATA			0
>  #define SUN4I_GPADC_IRQ_TEMP_DATA			1
>  

Re: [PATCH 6/7] iio: adc: sun4i-gpadc-iio: add support for H6 thermal sensor

[Lee Jones]

On Fri, 03 May 2019, Yangtao Li wrote:

> This patch adds support for the H6 ths sensor.
> 
> TODO: calibrate thermal sensor by using information from sid.
> 
> Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
> ---
>  drivers/iio/adc/sun4i-gpadc-iio.c | 65 +++++++++++++++++++++++++++++++
>  include/linux/mfd/sun4i-gpadc.h   |  9 +++++

For my own reference:
  Acked-for-MFD-by: Lee Jones <lee.jones@linaro.org>

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

[PATCH 7/7] iio: adc: sun4i-gpadc-iio convert to SPDX license tags

[Yangtao Li]

Updates license to use SPDX-License-Identifier.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
---
 drivers/iio/adc/sun4i-gpadc-iio.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c
index 9b6fc592f54c..cf2bf3ab3342 100644
--- a/drivers/iio/adc/sun4i-gpadc-iio.c
+++ b/drivers/iio/adc/sun4i-gpadc-iio.c
@@ -1,11 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0+
 /* ADC driver for sunxi platforms' (A10, A13 and A31) GPADC
  *
  * Copyright (c) 2016 Quentin Schulz <quentin.schulz@free-electrons.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.
- *
  * The Allwinner SoCs all have an ADC that can also act as a touchscreen
  * controller and a thermal sensor.
  * The thermal sensor works only when the ADC acts as a touchscreen controller
-- 
2.17.1

Re: [PATCH 7/7] iio: adc: sun4i-gpadc-iio convert to SPDX license tags

[Maxime Ripard]

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On Fri, May 03, 2019 at 03:28:13AM -0400, Yangtao Li wrote:
> Updates license to use SPDX-License-Identifier.
>
> Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
> ---
>  drivers/iio/adc/sun4i-gpadc-iio.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c
> index 9b6fc592f54c..cf2bf3ab3342 100644
> --- a/drivers/iio/adc/sun4i-gpadc-iio.c
> +++ b/drivers/iio/adc/sun4i-gpadc-iio.c
> @@ -1,11 +1,8 @@
> +// SPDX-License-Identifier: GPL-2.0+
>  /* ADC driver for sunxi platforms' (A10, A13 and A31) GPADC
>   *
>   * Copyright (c) 2016 Quentin Schulz <quentin.schulz@free-electrons.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.
> - *

The license here is GPL2 only, not GPL2 or later.

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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