[v12,3/5] iio: adc: mt6370: Add MediaTek MT6370 support

Commit Message

ChiaEn Wu Sept. 23, 2022, 2:51 a.m. UTC

From: ChiaEn Wu <[e-mail]>

MediaTek MT6370 is a SubPMIC consisting of a single cell battery charger
with ADC monitoring, RGB LEDs, dual channel flashlight, WLED backlight
driver, display bias voltage supply, one general purpose LDO, and the
USB Type-C & PD controller complies with the latest USB Type-C and PD
standards.

Add support for the MT6370 ADC driver for system monitoring, including
charger current, voltage, and temperature.

Reviewed-by: AngeloGioacchino Del Regno <[e-mail]>
Reviewed-by: Andy Shevchenko <[e-mail]>
Acked-by: Jonathan Cameron <[e-mail]>
Signed-off-by: ChiaEn Wu <[e-mail]>
---
 drivers/iio/adc/Kconfig      |  12 ++
 drivers/iio/adc/Makefile     |   1 +
 drivers/iio/adc/mt6370-adc.c | 305 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 318 insertions(+)
 create mode 100644 drivers/iio/adc/mt6370-adc.c

Comments

Jonathan Cameron Sept. 24, 2022, 2:55 p.m. UTC | #1

On Fri, 23 Sep 2022 10:51:24 +0800
ChiaEn Wu <[e-mail]> wrote:

> From: ChiaEn Wu <[e-mail]>
> 
> MediaTek MT6370 is a SubPMIC consisting of a single cell battery charger
> with ADC monitoring, RGB LEDs, dual channel flashlight, WLED backlight
> driver, display bias voltage supply, one general purpose LDO, and the
> USB Type-C & PD controller complies with the latest USB Type-C and PD
> standards.
> 
> Add support for the MT6370 ADC driver for system monitoring, including
> charger current, voltage, and temperature.
> 
> Reviewed-by: AngeloGioacchino Del Regno <[e-mail]>
> Reviewed-by: Andy Shevchenko <[e-mail]>
> Acked-by: Jonathan Cameron <[e-mail]>
> Signed-off-by: ChiaEn Wu <[e-mail]>

This will have to either wait for next cycle, or go through mfd because
of the dt-bindings include which is in the mfd tree.

Please make those dependencies clear in new versions.

+CC Lee

Thanks,

Jonathan


> ---
>  drivers/iio/adc/Kconfig      |  12 ++
>  drivers/iio/adc/Makefile     |   1 +
>  drivers/iio/adc/mt6370-adc.c | 305 +++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 318 insertions(+)
>  create mode 100644 drivers/iio/adc/mt6370-adc.c
> 
> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
> index 7fe5930..995cbb5 100644
> --- a/drivers/iio/adc/Kconfig
> +++ b/drivers/iio/adc/Kconfig
> @@ -736,6 +736,18 @@ config MEDIATEK_MT6360_ADC
>  	  is used in smartphones and tablets and supports a 11 channel
>  	  general purpose ADC.
>  
> +config MEDIATEK_MT6370_ADC
> +	tristate "MediaTek MT6370 ADC driver"
> +	depends on MFD_MT6370
> +	help
> +	  Say yes here to enable MediaTek MT6370 ADC support.
> +
> +	  This ADC driver provides 9 channels for system monitoring (charger
> +	  current, voltage, and temperature).
> +
> +	  This driver can also be built as a module. If so, the module
> +	  will be called "mt6370-adc".
> +
>  config MEDIATEK_MT6577_AUXADC
>  	tristate "MediaTek AUXADC driver"
>  	depends on ARCH_MEDIATEK || COMPILE_TEST
> diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
> index 1772a54..c6bc35f 100644
> --- a/drivers/iio/adc/Makefile
> +++ b/drivers/iio/adc/Makefile
> @@ -68,6 +68,7 @@ obj-$(CONFIG_MCP320X) += mcp320x.o
>  obj-$(CONFIG_MCP3422) += mcp3422.o
>  obj-$(CONFIG_MCP3911) += mcp3911.o
>  obj-$(CONFIG_MEDIATEK_MT6360_ADC) += mt6360-adc.o
> +obj-$(CONFIG_MEDIATEK_MT6370_ADC) += mt6370-adc.o
>  obj-$(CONFIG_MEDIATEK_MT6577_AUXADC) += mt6577_auxadc.o
>  obj-$(CONFIG_MEN_Z188_ADC) += men_z188_adc.o
>  obj-$(CONFIG_MESON_SARADC) += meson_saradc.o
> diff --git a/drivers/iio/adc/mt6370-adc.c b/drivers/iio/adc/mt6370-adc.c
> new file mode 100644
> index 0000000..2a46471
> --- /dev/null
> +++ b/drivers/iio/adc/mt6370-adc.c
> @@ -0,0 +1,305 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2022 Richtek Technology Corp.
> + *
> + * Author: ChiaEn Wu <[e-mail]>
> + */
> +
> +#include <linux/bits.h>
> +#include <linux/bitfield.h>
> +#include <linux/iio/iio.h>
> +#include <linux/kernel.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/sysfs.h>
> +#include <linux/units.h>
> +
> +#include <dt-bindings/iio/adc/mediatek,mt6370_adc.h>
> +
> +#define MT6370_REG_CHG_CTRL3		0x113
> +#define MT6370_REG_CHG_CTRL7		0x117
> +#define MT6370_REG_CHG_ADC		0x121
> +#define MT6370_REG_ADC_DATA_H		0x14C
> +
> +#define MT6370_ADC_START_MASK		BIT(0)
> +#define MT6370_ADC_IN_SEL_MASK		GENMASK(7, 4)
> +#define MT6370_AICR_ICHG_MASK		GENMASK(7, 2)
> +
> +#define MT6370_AICR_100_mA		0x0
> +#define MT6370_AICR_150_mA		0x1
> +#define MT6370_AICR_200_mA		0x2
> +#define MT6370_AICR_250_mA		0x3
> +#define MT6370_AICR_300_mA		0x4
> +#define MT6370_AICR_350_mA		0x5
> +
> +#define MT6370_ICHG_100_mA		0x0
> +#define MT6370_ICHG_200_mA		0x1
> +#define MT6370_ICHG_300_mA		0x2
> +#define MT6370_ICHG_400_mA		0x3
> +#define MT6370_ICHG_500_mA		0x4
> +#define MT6370_ICHG_600_mA		0x5
> +#define MT6370_ICHG_700_mA		0x6
> +#define MT6370_ICHG_800_mA		0x7
> +
> +#define ADC_CONV_TIME_MS		35
> +#define ADC_CONV_POLLING_TIME_US	1000
> +
> +struct mt6370_adc_data {
> +	struct device *dev;
> +	struct regmap *regmap;
> +	/*
> +	 * This mutex lock is for preventing the different ADC channels
> +	 * from being read at the same time.
> +	 */
> +	struct mutex adc_lock;
> +};
> +
> +static int mt6370_adc_read_channel(struct mt6370_adc_data *priv, int chan,
> +				   unsigned long addr, int *val)
> +{
> +	unsigned int reg_val;
> +	__be16 be_val;
> +	int ret;
> +
> +	mutex_lock(&priv->adc_lock);
> +
> +	reg_val = MT6370_ADC_START_MASK |
> +		  FIELD_PREP(MT6370_ADC_IN_SEL_MASK, addr);
> +	ret = regmap_write(priv->regmap, MT6370_REG_CHG_ADC, reg_val);
> +	if (ret)
> +		goto adc_unlock;
> +
> +	msleep(ADC_CONV_TIME_MS);
> +
> +	ret = regmap_read_poll_timeout(priv->regmap,
> +				       MT6370_REG_CHG_ADC, reg_val,
> +				       !(reg_val & MT6370_ADC_START_MASK),
> +				       ADC_CONV_POLLING_TIME_US,
> +				       ADC_CONV_TIME_MS * MILLI * 3);
> +	if (ret) {
> +		dev_err(priv->dev, "Failed to read ADC register (%d)\n", ret);
> +		goto adc_unlock;
> +	}
> +
> +	ret = regmap_raw_read(priv->regmap, MT6370_REG_ADC_DATA_H,
> +			      &be_val, sizeof(be_val));
> +	if (ret)
> +		goto adc_unlock;
> +
> +	*val = be16_to_cpu(be_val);
> +	ret = IIO_VAL_INT;
> +
> +adc_unlock:
> +	mutex_unlock(&priv->adc_lock);
> +
> +	return ret;
> +}
> +
> +static int mt6370_adc_read_scale(struct mt6370_adc_data *priv,
> +				 int chan, int *val1, int *val2)
> +{
> +	unsigned int reg_val;
> +	int ret;
> +
> +	switch (chan) {
> +	case MT6370_CHAN_VBAT:
> +	case MT6370_CHAN_VSYS:
> +	case MT6370_CHAN_CHG_VDDP:
> +		*val1 = 5;
> +		return IIO_VAL_INT;
> +	case MT6370_CHAN_IBUS:
> +		ret = regmap_read(priv->regmap, MT6370_REG_CHG_CTRL3, &reg_val);
> +		if (ret)
> +			return ret;
> +
> +		reg_val = FIELD_GET(MT6370_AICR_ICHG_MASK, reg_val);
> +		switch (reg_val) {
> +		case MT6370_AICR_100_mA:
> +		case MT6370_AICR_150_mA:
> +		case MT6370_AICR_200_mA:
> +		case MT6370_AICR_250_mA:
> +		case MT6370_AICR_300_mA:
> +		case MT6370_AICR_350_mA:
> +			*val1 = 3350;
> +			break;
> +		default:
> +			*val1 = 5000;
> +			break;
> +		}
> +
> +		*val2 = 100;
> +
> +		return IIO_VAL_FRACTIONAL;
> +	case MT6370_CHAN_IBAT:
> +		ret = regmap_read(priv->regmap, MT6370_REG_CHG_CTRL7, &reg_val);
> +		if (ret)
> +			return ret;
> +
> +		reg_val = FIELD_GET(MT6370_AICR_ICHG_MASK, reg_val);
> +		switch (reg_val) {
> +		case MT6370_ICHG_100_mA:
> +		case MT6370_ICHG_200_mA:
> +		case MT6370_ICHG_300_mA:
> +		case MT6370_ICHG_400_mA:
> +			*val1 = 2375;
> +			break;
> +		case MT6370_ICHG_500_mA:
> +		case MT6370_ICHG_600_mA:
> +		case MT6370_ICHG_700_mA:
> +		case MT6370_ICHG_800_mA:
> +			*val1 = 2680;
> +			break;
> +		default:
> +			*val1 = 5000;
> +			break;
> +		}
> +
> +		*val2 = 100;
> +
> +		return IIO_VAL_FRACTIONAL;
> +	case MT6370_CHAN_VBUSDIV5:
> +		*val1 = 25;
> +		return IIO_VAL_INT;
> +	case MT6370_CHAN_VBUSDIV2:
> +		*val1 = 50;
> +		return IIO_VAL_INT;
> +	case MT6370_CHAN_TS_BAT:
> +		*val1 = 25;
> +		*val2 = 10000;
> +		return IIO_VAL_FRACTIONAL;
> +	case MT6370_CHAN_TEMP_JC:
> +		*val1 = 2000;
> +		return IIO_VAL_FRACTIONAL;
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +static int mt6370_adc_read_offset(struct mt6370_adc_data *priv,
> +				  int chan, int *val)
> +{
> +	*val = -20;
> +
> +	return IIO_VAL_INT;
> +}
> +
> +static int mt6370_adc_read_raw(struct iio_dev *iio_dev,
> +			       const struct iio_chan_spec *chan,
> +			       int *val, int *val2, long mask)
> +{
> +	struct mt6370_adc_data *priv = iio_priv(iio_dev);
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		return mt6370_adc_read_channel(priv, chan->channel,
> +					       chan->address, val);
> +	case IIO_CHAN_INFO_SCALE:
> +		return mt6370_adc_read_scale(priv, chan->channel, val, val2);
> +	case IIO_CHAN_INFO_OFFSET:
> +		return mt6370_adc_read_offset(priv, chan->channel, val);
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +static const char * const mt6370_channel_labels[MT6370_CHAN_MAX] = {
> +	[MT6370_CHAN_VBUSDIV5] = "vbusdiv5",
> +	[MT6370_CHAN_VBUSDIV2] = "vbusdiv2",
> +	[MT6370_CHAN_VSYS] = "vsys",
> +	[MT6370_CHAN_VBAT] = "vbat",
> +	[MT6370_CHAN_TS_BAT] = "ts_bat",
> +	[MT6370_CHAN_IBUS] = "ibus",
> +	[MT6370_CHAN_IBAT] = "ibat",
> +	[MT6370_CHAN_CHG_VDDP] = "chg_vddp",
> +	[MT6370_CHAN_TEMP_JC] = "temp_jc",
> +};
> +
> +static int mt6370_adc_read_label(struct iio_dev *iio_dev,
> +				 struct iio_chan_spec const *chan, char *label)
> +{
> +	return sysfs_emit(label, "%s\n", mt6370_channel_labels[chan->channel]);
> +}
> +
> +static const struct iio_info mt6370_adc_iio_info = {
> +	.read_raw = mt6370_adc_read_raw,
> +	.read_label = mt6370_adc_read_label,
> +};
> +
> +#define MT6370_ADC_CHAN(_idx, _type, _addr, _extra_info) {	\
> +	.type = _type,						\
> +	.channel = MT6370_CHAN_##_idx,				\
> +	.address = _addr,					\
> +	.scan_index = MT6370_CHAN_##_idx,			\
> +	.indexed = 1,						\
> +	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
> +			      BIT(IIO_CHAN_INFO_SCALE) |	\
> +			      _extra_info,			\
> +}
> +
> +static const struct iio_chan_spec mt6370_adc_channels[] = {
> +	MT6370_ADC_CHAN(VBUSDIV5, IIO_VOLTAGE, 1, 0),
> +	MT6370_ADC_CHAN(VBUSDIV2, IIO_VOLTAGE, 2, 0),
> +	MT6370_ADC_CHAN(VSYS, IIO_VOLTAGE, 3, 0),
> +	MT6370_ADC_CHAN(VBAT, IIO_VOLTAGE, 4, 0),
> +	MT6370_ADC_CHAN(TS_BAT, IIO_VOLTAGE, 6, 0),
> +	MT6370_ADC_CHAN(IBUS, IIO_CURRENT, 8, 0),
> +	MT6370_ADC_CHAN(IBAT, IIO_CURRENT, 9, 0),
> +	MT6370_ADC_CHAN(CHG_VDDP, IIO_VOLTAGE, 11, 0),
> +	MT6370_ADC_CHAN(TEMP_JC, IIO_TEMP, 12, BIT(IIO_CHAN_INFO_OFFSET)),
> +};
> +
> +static int mt6370_adc_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct mt6370_adc_data *priv;
> +	struct iio_dev *indio_dev;
> +	struct regmap *regmap;
> +	int ret;
> +
> +	regmap = dev_get_regmap(pdev->dev.parent, NULL);
> +	if (!regmap)
> +		return dev_err_probe(dev, -ENODEV, "Failed to get regmap\n");
> +
> +	indio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
> +	if (!indio_dev)
> +		return -ENOMEM;
> +
> +	priv = iio_priv(indio_dev);
> +	priv->dev = dev;
> +	priv->regmap = regmap;
> +	mutex_init(&priv->adc_lock);
> +
> +	ret = regmap_write(priv->regmap, MT6370_REG_CHG_ADC, 0);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "Failed to reset ADC\n");
> +
> +	indio_dev->name = "mt6370-adc";
> +	indio_dev->info = &mt6370_adc_iio_info;
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +	indio_dev->channels = mt6370_adc_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(mt6370_adc_channels);
> +
> +	return devm_iio_device_register(dev, indio_dev);
> +}
> +
> +static const struct of_device_id mt6370_adc_of_id[] = {
> +	{ .compatible = "mediatek,mt6370-adc", },
> +	{}
> +};
> +MODULE_DEVICE_TABLE(of, mt6370_adc_of_id);
> +
> +static struct platform_driver mt6370_adc_driver = {
> +	.driver = {
> +		.name = "mt6370-adc",
> +		.of_match_table = mt6370_adc_of_id,
> +	},
> +	.probe = mt6370_adc_probe,
> +};
> +module_platform_driver(mt6370_adc_driver);
> +
> +MODULE_AUTHOR("ChiaEn Wu <[e-mail]>");
> +MODULE_DESCRIPTION("MT6370 ADC Driver");
> +MODULE_LICENSE("GPL v2");

Lee Jones Sept. 26, 2022, 7:46 a.m. UTC | #2

On Sat, 24 Sep 2022, Jonathan Cameron wrote:

> On Fri, 23 Sep 2022 10:51:24 +0800
> ChiaEn Wu <[e-mail]> wrote:
> 
> > From: ChiaEn Wu <[e-mail]>
> > 
> > MediaTek MT6370 is a SubPMIC consisting of a single cell battery charger
> > with ADC monitoring, RGB LEDs, dual channel flashlight, WLED backlight
> > driver, display bias voltage supply, one general purpose LDO, and the
> > USB Type-C & PD controller complies with the latest USB Type-C and PD
> > standards.
> > 
> > Add support for the MT6370 ADC driver for system monitoring, including
> > charger current, voltage, and temperature.
> > 
> > Reviewed-by: AngeloGioacchino Del Regno <[e-mail]>
> > Reviewed-by: Andy Shevchenko <[e-mail]>
> > Acked-by: Jonathan Cameron <[e-mail]>
> > Signed-off-by: ChiaEn Wu <[e-mail]>
> 
> This will have to either wait for next cycle, or go through mfd because
> of the dt-bindings include which is in the mfd tree.
> 
> Please make those dependencies clear in new versions.

If the bindings come together in -next, then subsequently in Mainline,
it shouldn't really matter.  It's only your IIO tree that the DT
tooling with complain about, right?

Rob Herring Sept. 26, 2022, 3:06 p.m. UTC | #3

On Mon, Sep 26, 2022 at 2:46 AM Lee Jones <[e-mail]> wrote:
>
> On Sat, 24 Sep 2022, Jonathan Cameron wrote:
>
> > On Fri, 23 Sep 2022 10:51:24 +0800
> > ChiaEn Wu <[e-mail]> wrote:
> >
> > > From: ChiaEn Wu <[e-mail]>
> > >
> > > MediaTek MT6370 is a SubPMIC consisting of a single cell battery charger
> > > with ADC monitoring, RGB LEDs, dual channel flashlight, WLED backlight
> > > driver, display bias voltage supply, one general purpose LDO, and the
> > > USB Type-C & PD controller complies with the latest USB Type-C and PD
> > > standards.
> > >
> > > Add support for the MT6370 ADC driver for system monitoring, including
> > > charger current, voltage, and temperature.
> > >
> > > Reviewed-by: AngeloGioacchino Del Regno <[e-mail]>
> > > Reviewed-by: Andy Shevchenko <[e-mail]>
> > > Acked-by: Jonathan Cameron <[e-mail]>
> > > Signed-off-by: ChiaEn Wu <[e-mail]>
> >
> > This will have to either wait for next cycle, or go through mfd because
> > of the dt-bindings include which is in the mfd tree.
> >
> > Please make those dependencies clear in new versions.
>
> If the bindings come together in -next, then subsequently in Mainline,
> it shouldn't really matter.

Except that the bindings haven't come together and at this point may
not for 6.1. linux-next has been warning for weeks because the child
device schemas haven't been applied. I've said it before, all the
schemas for MFD devices need to be applied together. Or at least the
MFD schema needs to get applied last.

Furthermore, subsequent versions of this don't get tested and we end
up with more warnings[1].

It's only your IIO tree that the DT
> tooling with complain about, right?

And the MFD tree...

Please apply the LED bindings (patches 1 and 2) so we can get the
existing warnings fixed and address any new warnings.

Rob

[1] https://lore.kernel.org/all/[e-mail]/

Lee Jones Sept. 28, 2022, 9:23 a.m. UTC | #4

On Mon, 26 Sep 2022, Rob Herring wrote:

> On Mon, Sep 26, 2022 at 2:46 AM Lee Jones <[e-mail]> wrote:
> >
> > On Sat, 24 Sep 2022, Jonathan Cameron wrote:
> >
> > > On Fri, 23 Sep 2022 10:51:24 +0800
> > > ChiaEn Wu <[e-mail]> wrote:
> > >
> > > > From: ChiaEn Wu <[e-mail]>
> > > >
> > > > MediaTek MT6370 is a SubPMIC consisting of a single cell battery charger
> > > > with ADC monitoring, RGB LEDs, dual channel flashlight, WLED backlight
> > > > driver, display bias voltage supply, one general purpose LDO, and the
> > > > USB Type-C & PD controller complies with the latest USB Type-C and PD
> > > > standards.
> > > >
> > > > Add support for the MT6370 ADC driver for system monitoring, including
> > > > charger current, voltage, and temperature.
> > > >
> > > > Reviewed-by: AngeloGioacchino Del Regno <[e-mail]>
> > > > Reviewed-by: Andy Shevchenko <[e-mail]>
> > > > Acked-by: Jonathan Cameron <[e-mail]>
> > > > Signed-off-by: ChiaEn Wu <[e-mail]>
> > >
> > > This will have to either wait for next cycle, or go through mfd because
> > > of the dt-bindings include which is in the mfd tree.
> > >
> > > Please make those dependencies clear in new versions.
> >
> > If the bindings come together in -next, then subsequently in Mainline,
> > it shouldn't really matter.
> 
> Except that the bindings haven't come together and at this point may
> not for 6.1. linux-next has been warning for weeks because the child
> device schemas haven't been applied. I've said it before, all the
> schemas for MFD devices need to be applied together. Or at least the
> MFD schema needs to get applied last.
> 
> Furthermore, subsequent versions of this don't get tested and we end
> up with more warnings[1].
> 
> It's only your IIO tree that the DT
> > tooling with complain about, right?
> 
> And the MFD tree...
> 
> Please apply the LED bindings (patches 1 and 2) so we can get the
> existing warnings fixed and address any new warnings.

Who usually applies LED bindings?  Looks as though they're good to go.

Rob Herring Sept. 29, 2022, 4:34 p.m. UTC | #5

On Wed, Sep 28, 2022 at 10:23:42AM +0100, Lee Jones wrote:
> On Mon, 26 Sep 2022, Rob Herring wrote:
> 
> > On Mon, Sep 26, 2022 at 2:46 AM Lee Jones <[e-mail]> wrote:
> > >
> > > On Sat, 24 Sep 2022, Jonathan Cameron wrote:
> > >
> > > > On Fri, 23 Sep 2022 10:51:24 +0800
> > > > ChiaEn Wu <[e-mail]> wrote:
> > > >
> > > > > From: ChiaEn Wu <[e-mail]>
> > > > >
> > > > > MediaTek MT6370 is a SubPMIC consisting of a single cell battery charger
> > > > > with ADC monitoring, RGB LEDs, dual channel flashlight, WLED backlight
> > > > > driver, display bias voltage supply, one general purpose LDO, and the
> > > > > USB Type-C & PD controller complies with the latest USB Type-C and PD
> > > > > standards.
> > > > >
> > > > > Add support for the MT6370 ADC driver for system monitoring, including
> > > > > charger current, voltage, and temperature.
> > > > >
> > > > > Reviewed-by: AngeloGioacchino Del Regno <[e-mail]>
> > > > > Reviewed-by: Andy Shevchenko <[e-mail]>
> > > > > Acked-by: Jonathan Cameron <[e-mail]>
> > > > > Signed-off-by: ChiaEn Wu <[e-mail]>
> > > >
> > > > This will have to either wait for next cycle, or go through mfd because
> > > > of the dt-bindings include which is in the mfd tree.
> > > >
> > > > Please make those dependencies clear in new versions.
> > >
> > > If the bindings come together in -next, then subsequently in Mainline,
> > > it shouldn't really matter.
> > 
> > Except that the bindings haven't come together and at this point may
> > not for 6.1. linux-next has been warning for weeks because the child
> > device schemas haven't been applied. I've said it before, all the
> > schemas for MFD devices need to be applied together. Or at least the
> > MFD schema needs to get applied last.
> > 
> > Furthermore, subsequent versions of this don't get tested and we end
> > up with more warnings[1].
> > 
> > It's only your IIO tree that the DT
> > > tooling with complain about, right?
> > 
> > And the MFD tree...
> > 
> > Please apply the LED bindings (patches 1 and 2) so we can get the
> > existing warnings fixed and address any new warnings.
> 
> Who usually applies LED bindings?  Looks as though they're good to go.

Pavel. The issue would be I don't know if the driver side is ready and 
those usually go together. Other than my complaining here, how's he 
supposed to know that the bindings at least need to be applied?

Again, the process here is not working. I've said before, all the 
bindings for an MFD need to go via 1 tree. You obviously don't agree, so 
propose something. The current process of no coordination doesn't work.

Rob

Lee Jones Sept. 29, 2022, 5:51 p.m. UTC | #6

On Thu, 29 Sep 2022, Rob Herring wrote:

> On Wed, Sep 28, 2022 at 10:23:42AM +0100, Lee Jones wrote:
> > On Mon, 26 Sep 2022, Rob Herring wrote:
> > 
> > > On Mon, Sep 26, 2022 at 2:46 AM Lee Jones <[e-mail]> wrote:
> > > >
> > > > On Sat, 24 Sep 2022, Jonathan Cameron wrote:
> > > >
> > > > > On Fri, 23 Sep 2022 10:51:24 +0800
> > > > > ChiaEn Wu <[e-mail]> wrote:
> > > > >
> > > > > > From: ChiaEn Wu <[e-mail]>
> > > > > >
> > > > > > MediaTek MT6370 is a SubPMIC consisting of a single cell battery charger
> > > > > > with ADC monitoring, RGB LEDs, dual channel flashlight, WLED backlight
> > > > > > driver, display bias voltage supply, one general purpose LDO, and the
> > > > > > USB Type-C & PD controller complies with the latest USB Type-C and PD
> > > > > > standards.
> > > > > >
> > > > > > Add support for the MT6370 ADC driver for system monitoring, including
> > > > > > charger current, voltage, and temperature.
> > > > > >
> > > > > > Reviewed-by: AngeloGioacchino Del Regno <[e-mail]>
> > > > > > Reviewed-by: Andy Shevchenko <[e-mail]>
> > > > > > Acked-by: Jonathan Cameron <[e-mail]>
> > > > > > Signed-off-by: ChiaEn Wu <[e-mail]>
> > > > >
> > > > > This will have to either wait for next cycle, or go through mfd because
> > > > > of the dt-bindings include which is in the mfd tree.
> > > > >
> > > > > Please make those dependencies clear in new versions.
> > > >
> > > > If the bindings come together in -next, then subsequently in Mainline,
> > > > it shouldn't really matter.
> > > 
> > > Except that the bindings haven't come together and at this point may
> > > not for 6.1. linux-next has been warning for weeks because the child
> > > device schemas haven't been applied. I've said it before, all the
> > > schemas for MFD devices need to be applied together. Or at least the
> > > MFD schema needs to get applied last.
> > > 
> > > Furthermore, subsequent versions of this don't get tested and we end
> > > up with more warnings[1].
> > > 
> > > It's only your IIO tree that the DT
> > > > tooling with complain about, right?
> > > 
> > > And the MFD tree...
> > > 
> > > Please apply the LED bindings (patches 1 and 2) so we can get the
> > > existing warnings fixed and address any new warnings.
> > 
> > Who usually applies LED bindings?  Looks as though they're good to go.
> 
> Pavel. The issue would be I don't know if the driver side is ready and 
> those usually go together. Other than my complaining here, how's he 
> supposed to know that the bindings at least need to be applied?
> 
> Again, the process here is not working. I've said before, all the 
> bindings for an MFD need to go via 1 tree. You obviously don't agree, so 
> propose something. The current process of no coordination doesn't work.

The solution would be for someone to create succinct immutable branches, like
I do for real code.  If someone would be happy to do that, I'd be more than
happy to pull from them.

I go to the effort of creating them to prevent actual build breakages,
however doing so to keep a documentation helper script happy is a step
too far for me personally, sorry.

Jonathan Cameron Oct. 1, 2022, 5:11 p.m. UTC | #7

On Thu, 29 Sep 2022 18:51:32 +0100
Lee Jones <[e-mail]> wrote:

> On Thu, 29 Sep 2022, Rob Herring wrote:
> 
> > On Wed, Sep 28, 2022 at 10:23:42AM +0100, Lee Jones wrote:  
> > > On Mon, 26 Sep 2022, Rob Herring wrote:
> > >   
> > > > On Mon, Sep 26, 2022 at 2:46 AM Lee Jones <[e-mail]> wrote:  
> > > > >
> > > > > On Sat, 24 Sep 2022, Jonathan Cameron wrote:
> > > > >  
> > > > > > On Fri, 23 Sep 2022 10:51:24 +0800
> > > > > > ChiaEn Wu <[e-mail]> wrote:
> > > > > >  
> > > > > > > From: ChiaEn Wu <[e-mail]>
> > > > > > >
> > > > > > > MediaTek MT6370 is a SubPMIC consisting of a single cell battery charger
> > > > > > > with ADC monitoring, RGB LEDs, dual channel flashlight, WLED backlight
> > > > > > > driver, display bias voltage supply, one general purpose LDO, and the
> > > > > > > USB Type-C & PD controller complies with the latest USB Type-C and PD
> > > > > > > standards.
> > > > > > >
> > > > > > > Add support for the MT6370 ADC driver for system monitoring, including
> > > > > > > charger current, voltage, and temperature.
> > > > > > >
> > > > > > > Reviewed-by: AngeloGioacchino Del Regno <[e-mail]>
> > > > > > > Reviewed-by: Andy Shevchenko <[e-mail]>
> > > > > > > Acked-by: Jonathan Cameron <[e-mail]>
> > > > > > > Signed-off-by: ChiaEn Wu <[e-mail]>  
> > > > > >
> > > > > > This will have to either wait for next cycle, or go through mfd because
> > > > > > of the dt-bindings include which is in the mfd tree.
> > > > > >
> > > > > > Please make those dependencies clear in new versions.  
> > > > >
> > > > > If the bindings come together in -next, then subsequently in Mainline,
> > > > > it shouldn't really matter.  
> > > > 
> > > > Except that the bindings haven't come together and at this point may
> > > > not for 6.1. linux-next has been warning for weeks because the child
> > > > device schemas haven't been applied. I've said it before, all the
> > > > schemas for MFD devices need to be applied together. Or at least the
> > > > MFD schema needs to get applied last.
> > > > 
> > > > Furthermore, subsequent versions of this don't get tested and we end
> > > > up with more warnings[1].
> > > > 
> > > > It's only your IIO tree that the DT  
> > > > > tooling with complain about, right?  
> > > > 
> > > > And the MFD tree...
> > > > 
> > > > Please apply the LED bindings (patches 1 and 2) so we can get the
> > > > existing warnings fixed and address any new warnings.  
> > > 
> > > Who usually applies LED bindings?  Looks as though they're good to go.  
> > 
> > Pavel. The issue would be I don't know if the driver side is ready and 
> > those usually go together. Other than my complaining here, how's he 
> > supposed to know that the bindings at least need to be applied?
> > 
> > Again, the process here is not working. I've said before, all the 
> > bindings for an MFD need to go via 1 tree. You obviously don't agree, so 
> > propose something. The current process of no coordination doesn't work.  
> 
> The solution would be for someone to create succinct immutable branches, like
> I do for real code.  If someone would be happy to do that, I'd be more than
> happy to pull from them.
> 
> I go to the effort of creating them to prevent actual build breakages,
> however doing so to keep a documentation helper script happy is a step
> too far for me personally, sorry.
> 

In this case the bindings include is included from the driver - not just the
binding.  Obviously there are dances to get around that by using the values
and replacing in following cycle, but that's not the case here!

Jonathan

Lee Jones Oct. 3, 2022, 7:38 a.m. UTC | #8

On Sat, 01 Oct 2022, Jonathan Cameron wrote:

> On Thu, 29 Sep 2022 18:51:32 +0100
> Lee Jones <[e-mail]> wrote:
> 
> > On Thu, 29 Sep 2022, Rob Herring wrote:
> > 
> > > On Wed, Sep 28, 2022 at 10:23:42AM +0100, Lee Jones wrote:  
> > > > On Mon, 26 Sep 2022, Rob Herring wrote:
> > > >   
> > > > > On Mon, Sep 26, 2022 at 2:46 AM Lee Jones <[e-mail]> wrote:  
> > > > > >
> > > > > > On Sat, 24 Sep 2022, Jonathan Cameron wrote:
> > > > > >  
> > > > > > > On Fri, 23 Sep 2022 10:51:24 +0800
> > > > > > > ChiaEn Wu <[e-mail]> wrote:
> > > > > > >  
> > > > > > > > From: ChiaEn Wu <[e-mail]>
> > > > > > > >
> > > > > > > > MediaTek MT6370 is a SubPMIC consisting of a single cell battery charger
> > > > > > > > with ADC monitoring, RGB LEDs, dual channel flashlight, WLED backlight
> > > > > > > > driver, display bias voltage supply, one general purpose LDO, and the
> > > > > > > > USB Type-C & PD controller complies with the latest USB Type-C and PD
> > > > > > > > standards.
> > > > > > > >
> > > > > > > > Add support for the MT6370 ADC driver for system monitoring, including
> > > > > > > > charger current, voltage, and temperature.
> > > > > > > >
> > > > > > > > Reviewed-by: AngeloGioacchino Del Regno <[e-mail]>
> > > > > > > > Reviewed-by: Andy Shevchenko <[e-mail]>
> > > > > > > > Acked-by: Jonathan Cameron <[e-mail]>
> > > > > > > > Signed-off-by: ChiaEn Wu <[e-mail]>  
> > > > > > >
> > > > > > > This will have to either wait for next cycle, or go through mfd because
> > > > > > > of the dt-bindings include which is in the mfd tree.
> > > > > > >
> > > > > > > Please make those dependencies clear in new versions.  
> > > > > >
> > > > > > If the bindings come together in -next, then subsequently in Mainline,
> > > > > > it shouldn't really matter.  
> > > > > 
> > > > > Except that the bindings haven't come together and at this point may
> > > > > not for 6.1. linux-next has been warning for weeks because the child
> > > > > device schemas haven't been applied. I've said it before, all the
> > > > > schemas for MFD devices need to be applied together. Or at least the
> > > > > MFD schema needs to get applied last.
> > > > > 
> > > > > Furthermore, subsequent versions of this don't get tested and we end
> > > > > up with more warnings[1].
> > > > > 
> > > > > It's only your IIO tree that the DT  
> > > > > > tooling with complain about, right?  
> > > > > 
> > > > > And the MFD tree...
> > > > > 
> > > > > Please apply the LED bindings (patches 1 and 2) so we can get the
> > > > > existing warnings fixed and address any new warnings.  
> > > > 
> > > > Who usually applies LED bindings?  Looks as though they're good to go.  
> > > 
> > > Pavel. The issue would be I don't know if the driver side is ready and 
> > > those usually go together. Other than my complaining here, how's he 
> > > supposed to know that the bindings at least need to be applied?
> > > 
> > > Again, the process here is not working. I've said before, all the 
> > > bindings for an MFD need to go via 1 tree. You obviously don't agree, so 
> > > propose something. The current process of no coordination doesn't work.  
> > 
> > The solution would be for someone to create succinct immutable branches, like
> > I do for real code.  If someone would be happy to do that, I'd be more than
> > happy to pull from them.
> > 
> > I go to the effort of creating them to prevent actual build breakages,
> > however doing so to keep a documentation helper script happy is a step
> > too far for me personally, sorry.
> > 
> 
> In this case the bindings include is included from the driver - not just the
> binding.  Obviously there are dances to get around that by using the values
> and replacing in following cycle, but that's not the case here!

The paragraphs above to not pertain to the use of shared include
files.  Obviously that would be a good case for the use of IBs.

Patch

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 7fe5930..995cbb5 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -736,6 +736,18 @@  config MEDIATEK_MT6360_ADC
 	  is used in smartphones and tablets and supports a 11 channel
 	  general purpose ADC.
 
+config MEDIATEK_MT6370_ADC
+	tristate "MediaTek MT6370 ADC driver"
+	depends on MFD_MT6370
+	help
+	  Say yes here to enable MediaTek MT6370 ADC support.
+
+	  This ADC driver provides 9 channels for system monitoring (charger
+	  current, voltage, and temperature).
+
+	  This driver can also be built as a module. If so, the module
+	  will be called "mt6370-adc".
+
 config MEDIATEK_MT6577_AUXADC
 	tristate "MediaTek AUXADC driver"
 	depends on ARCH_MEDIATEK || COMPILE_TEST
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 1772a54..c6bc35f 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -68,6 +68,7 @@  obj-$(CONFIG_MCP320X) += mcp320x.o
 obj-$(CONFIG_MCP3422) += mcp3422.o
 obj-$(CONFIG_MCP3911) += mcp3911.o
 obj-$(CONFIG_MEDIATEK_MT6360_ADC) += mt6360-adc.o
+obj-$(CONFIG_MEDIATEK_MT6370_ADC) += mt6370-adc.o
 obj-$(CONFIG_MEDIATEK_MT6577_AUXADC) += mt6577_auxadc.o
 obj-$(CONFIG_MEN_Z188_ADC) += men_z188_adc.o
 obj-$(CONFIG_MESON_SARADC) += meson_saradc.o
diff --git a/drivers/iio/adc/mt6370-adc.c b/drivers/iio/adc/mt6370-adc.c
new file mode 100644
index 0000000..2a46471
--- /dev/null
+++ b/drivers/iio/adc/mt6370-adc.c
@@ -0,0 +1,305 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2022 Richtek Technology Corp.
+ *
+ * Author: ChiaEn Wu <[e-mail]>
+ */
+
+#include <linux/bits.h>
+#include <linux/bitfield.h>
+#include <linux/iio/iio.h>
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/sysfs.h>
+#include <linux/units.h>
+
+#include <dt-bindings/iio/adc/mediatek,mt6370_adc.h>
+
+#define MT6370_REG_CHG_CTRL3		0x113
+#define MT6370_REG_CHG_CTRL7		0x117
+#define MT6370_REG_CHG_ADC		0x121
+#define MT6370_REG_ADC_DATA_H		0x14C
+
+#define MT6370_ADC_START_MASK		BIT(0)
+#define MT6370_ADC_IN_SEL_MASK		GENMASK(7, 4)
+#define MT6370_AICR_ICHG_MASK		GENMASK(7, 2)
+
+#define MT6370_AICR_100_mA		0x0
+#define MT6370_AICR_150_mA		0x1
+#define MT6370_AICR_200_mA		0x2
+#define MT6370_AICR_250_mA		0x3
+#define MT6370_AICR_300_mA		0x4
+#define MT6370_AICR_350_mA		0x5
+
+#define MT6370_ICHG_100_mA		0x0
+#define MT6370_ICHG_200_mA		0x1
+#define MT6370_ICHG_300_mA		0x2
+#define MT6370_ICHG_400_mA		0x3
+#define MT6370_ICHG_500_mA		0x4
+#define MT6370_ICHG_600_mA		0x5
+#define MT6370_ICHG_700_mA		0x6
+#define MT6370_ICHG_800_mA		0x7
+
+#define ADC_CONV_TIME_MS		35
+#define ADC_CONV_POLLING_TIME_US	1000
+
+struct mt6370_adc_data {
+	struct device *dev;
+	struct regmap *regmap;
+	/*
+	 * This mutex lock is for preventing the different ADC channels
+	 * from being read at the same time.
+	 */
+	struct mutex adc_lock;
+};
+
+static int mt6370_adc_read_channel(struct mt6370_adc_data *priv, int chan,
+				   unsigned long addr, int *val)
+{
+	unsigned int reg_val;
+	__be16 be_val;
+	int ret;
+
+	mutex_lock(&priv->adc_lock);
+
+	reg_val = MT6370_ADC_START_MASK |
+		  FIELD_PREP(MT6370_ADC_IN_SEL_MASK, addr);
+	ret = regmap_write(priv->regmap, MT6370_REG_CHG_ADC, reg_val);
+	if (ret)
+		goto adc_unlock;
+
+	msleep(ADC_CONV_TIME_MS);
+
+	ret = regmap_read_poll_timeout(priv->regmap,
+				       MT6370_REG_CHG_ADC, reg_val,
+				       !(reg_val & MT6370_ADC_START_MASK),
+				       ADC_CONV_POLLING_TIME_US,
+				       ADC_CONV_TIME_MS * MILLI * 3);
+	if (ret) {
+		dev_err(priv->dev, "Failed to read ADC register (%d)\n", ret);
+		goto adc_unlock;
+	}
+
+	ret = regmap_raw_read(priv->regmap, MT6370_REG_ADC_DATA_H,
+			      &be_val, sizeof(be_val));
+	if (ret)
+		goto adc_unlock;
+
+	*val = be16_to_cpu(be_val);
+	ret = IIO_VAL_INT;
+
+adc_unlock:
+	mutex_unlock(&priv->adc_lock);
+
+	return ret;
+}
+
+static int mt6370_adc_read_scale(struct mt6370_adc_data *priv,
+				 int chan, int *val1, int *val2)
+{
+	unsigned int reg_val;
+	int ret;
+
+	switch (chan) {
+	case MT6370_CHAN_VBAT:
+	case MT6370_CHAN_VSYS:
+	case MT6370_CHAN_CHG_VDDP:
+		*val1 = 5;
+		return IIO_VAL_INT;
+	case MT6370_CHAN_IBUS:
+		ret = regmap_read(priv->regmap, MT6370_REG_CHG_CTRL3, &reg_val);
+		if (ret)
+			return ret;
+
+		reg_val = FIELD_GET(MT6370_AICR_ICHG_MASK, reg_val);
+		switch (reg_val) {
+		case MT6370_AICR_100_mA:
+		case MT6370_AICR_150_mA:
+		case MT6370_AICR_200_mA:
+		case MT6370_AICR_250_mA:
+		case MT6370_AICR_300_mA:
+		case MT6370_AICR_350_mA:
+			*val1 = 3350;
+			break;
+		default:
+			*val1 = 5000;
+			break;
+		}
+
+		*val2 = 100;
+
+		return IIO_VAL_FRACTIONAL;
+	case MT6370_CHAN_IBAT:
+		ret = regmap_read(priv->regmap, MT6370_REG_CHG_CTRL7, &reg_val);
+		if (ret)
+			return ret;
+
+		reg_val = FIELD_GET(MT6370_AICR_ICHG_MASK, reg_val);
+		switch (reg_val) {
+		case MT6370_ICHG_100_mA:
+		case MT6370_ICHG_200_mA:
+		case MT6370_ICHG_300_mA:
+		case MT6370_ICHG_400_mA:
+			*val1 = 2375;
+			break;
+		case MT6370_ICHG_500_mA:
+		case MT6370_ICHG_600_mA:
+		case MT6370_ICHG_700_mA:
+		case MT6370_ICHG_800_mA:
+			*val1 = 2680;
+			break;
+		default:
+			*val1 = 5000;
+			break;
+		}
+
+		*val2 = 100;
+
+		return IIO_VAL_FRACTIONAL;
+	case MT6370_CHAN_VBUSDIV5:
+		*val1 = 25;
+		return IIO_VAL_INT;
+	case MT6370_CHAN_VBUSDIV2:
+		*val1 = 50;
+		return IIO_VAL_INT;
+	case MT6370_CHAN_TS_BAT:
+		*val1 = 25;
+		*val2 = 10000;
+		return IIO_VAL_FRACTIONAL;
+	case MT6370_CHAN_TEMP_JC:
+		*val1 = 2000;
+		return IIO_VAL_FRACTIONAL;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int mt6370_adc_read_offset(struct mt6370_adc_data *priv,
+				  int chan, int *val)
+{
+	*val = -20;
+
+	return IIO_VAL_INT;
+}
+
+static int mt6370_adc_read_raw(struct iio_dev *iio_dev,
+			       const struct iio_chan_spec *chan,
+			       int *val, int *val2, long mask)
+{
+	struct mt6370_adc_data *priv = iio_priv(iio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		return mt6370_adc_read_channel(priv, chan->channel,
+					       chan->address, val);
+	case IIO_CHAN_INFO_SCALE:
+		return mt6370_adc_read_scale(priv, chan->channel, val, val2);
+	case IIO_CHAN_INFO_OFFSET:
+		return mt6370_adc_read_offset(priv, chan->channel, val);
+	default:
+		return -EINVAL;
+	}
+}
+
+static const char * const mt6370_channel_labels[MT6370_CHAN_MAX] = {
+	[MT6370_CHAN_VBUSDIV5] = "vbusdiv5",
+	[MT6370_CHAN_VBUSDIV2] = "vbusdiv2",
+	[MT6370_CHAN_VSYS] = "vsys",
+	[MT6370_CHAN_VBAT] = "vbat",
+	[MT6370_CHAN_TS_BAT] = "ts_bat",
+	[MT6370_CHAN_IBUS] = "ibus",
+	[MT6370_CHAN_IBAT] = "ibat",
+	[MT6370_CHAN_CHG_VDDP] = "chg_vddp",
+	[MT6370_CHAN_TEMP_JC] = "temp_jc",
+};
+
+static int mt6370_adc_read_label(struct iio_dev *iio_dev,
+				 struct iio_chan_spec const *chan, char *label)
+{
+	return sysfs_emit(label, "%s\n", mt6370_channel_labels[chan->channel]);
+}
+
+static const struct iio_info mt6370_adc_iio_info = {
+	.read_raw = mt6370_adc_read_raw,
+	.read_label = mt6370_adc_read_label,
+};
+
+#define MT6370_ADC_CHAN(_idx, _type, _addr, _extra_info) {	\
+	.type = _type,						\
+	.channel = MT6370_CHAN_##_idx,				\
+	.address = _addr,					\
+	.scan_index = MT6370_CHAN_##_idx,			\
+	.indexed = 1,						\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
+			      BIT(IIO_CHAN_INFO_SCALE) |	\
+			      _extra_info,			\
+}
+
+static const struct iio_chan_spec mt6370_adc_channels[] = {
+	MT6370_ADC_CHAN(VBUSDIV5, IIO_VOLTAGE, 1, 0),
+	MT6370_ADC_CHAN(VBUSDIV2, IIO_VOLTAGE, 2, 0),
+	MT6370_ADC_CHAN(VSYS, IIO_VOLTAGE, 3, 0),
+	MT6370_ADC_CHAN(VBAT, IIO_VOLTAGE, 4, 0),
+	MT6370_ADC_CHAN(TS_BAT, IIO_VOLTAGE, 6, 0),
+	MT6370_ADC_CHAN(IBUS, IIO_CURRENT, 8, 0),
+	MT6370_ADC_CHAN(IBAT, IIO_CURRENT, 9, 0),
+	MT6370_ADC_CHAN(CHG_VDDP, IIO_VOLTAGE, 11, 0),
+	MT6370_ADC_CHAN(TEMP_JC, IIO_TEMP, 12, BIT(IIO_CHAN_INFO_OFFSET)),
+};
+
+static int mt6370_adc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct mt6370_adc_data *priv;
+	struct iio_dev *indio_dev;
+	struct regmap *regmap;
+	int ret;
+
+	regmap = dev_get_regmap(pdev->dev.parent, NULL);
+	if (!regmap)
+		return dev_err_probe(dev, -ENODEV, "Failed to get regmap\n");
+
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	priv = iio_priv(indio_dev);
+	priv->dev = dev;
+	priv->regmap = regmap;
+	mutex_init(&priv->adc_lock);
+
+	ret = regmap_write(priv->regmap, MT6370_REG_CHG_ADC, 0);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to reset ADC\n");
+
+	indio_dev->name = "mt6370-adc";
+	indio_dev->info = &mt6370_adc_iio_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = mt6370_adc_channels;
+	indio_dev->num_channels = ARRAY_SIZE(mt6370_adc_channels);
+
+	return devm_iio_device_register(dev, indio_dev);
+}
+
+static const struct of_device_id mt6370_adc_of_id[] = {
+	{ .compatible = "mediatek,mt6370-adc", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, mt6370_adc_of_id);
+
+static struct platform_driver mt6370_adc_driver = {
+	.driver = {
+		.name = "mt6370-adc",
+		.of_match_table = mt6370_adc_of_id,
+	},
+	.probe = mt6370_adc_probe,
+};
+module_platform_driver(mt6370_adc_driver);
+
+MODULE_AUTHOR("ChiaEn Wu <[e-mail]>");
+MODULE_DESCRIPTION("MT6370 ADC Driver");
+MODULE_LICENSE("GPL v2");