iio: adc: add support for X-Powers AXP20X and AXP22X PMICs ADCs

The X-Powers AXP20X and AXP22X PMICs have multiple ADCs. They expose the
battery voltage, battery charge and discharge currents, AC-in and VBUS
voltages and currents, 2 GPIOs muxable in ADC mode and PMIC temperature.

This adds support for most of AXP20X and AXP22X ADCs.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Reviewed-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

3 files changed, 628 insertions, 0 deletions

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 5d134053a1bc..ff5ad3be55b4 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -154,6 +154,16 @@ config AT91_SAMA5D2_ADC
           To compile this driver as a module, choose M here: the module will be
           called at91-sama5d2_adc.
 
+config AXP20X_ADC
+        tristate "X-Powers AXP20X and AXP22X ADC driver"
+        depends on MFD_AXP20X
+        help
+          Say yes here to have support for X-Powers power management IC (PMIC)
+          AXP20X and AXP22X ADC devices.
+
+          To compile this driver as a module, choose M here: the module will be
+          called axp20x_adc.
+
 config AXP288_ADC
         tristate "X-Powers AXP288 ADC driver"
         depends on MFD_AXP20X
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 54b5f7259063..a01de757f42c 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_AD7887) += ad7887.o
 obj-$(CONFIG_AD799X) += ad799x.o
 obj-$(CONFIG_AT91_ADC) += at91_adc.o
 obj-$(CONFIG_AT91_SAMA5D2_ADC) += at91-sama5d2_adc.o
+obj-$(CONFIG_AXP20X_ADC) += axp20x_adc.o
 obj-$(CONFIG_AXP288_ADC) += axp288_adc.o
 obj-$(CONFIG_BCM_IPROC_ADC) += bcm_iproc_adc.o
 obj-$(CONFIG_BERLIN2_ADC) += berlin2-adc.o
diff --git a/drivers/iio/adc/axp20x_adc.c b/drivers/iio/adc/axp20x_adc.c
new file mode 100644
index 000000000000..11e177180ea0
--- /dev/null
+++ b/drivers/iio/adc/axp20x_adc.c
@@ -0,0 +1,617 @@
+/* ADC driver for AXP20X and AXP22X PMICs
+ *
+ * Copyright (c) 2016 Free Electrons NextThing Co.
+ *      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.
+ */
+
+#include <linux/completion.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/thermal.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/driver.h>
+#include <linux/iio/machine.h>
+#include <linux/mfd/axp20x.h>
+
+#define AXP20X_ADC_EN1_MASK                     GENMASK(7, 0)
+
+#define AXP20X_ADC_EN2_MASK                     (GENMASK(3, 2) | BIT(7))
+#define AXP22X_ADC_EN1_MASK                     (GENMASK(7, 5) | BIT(0))
+
+#define AXP20X_GPIO10_IN_RANGE_GPIO0            BIT(0)
+#define AXP20X_GPIO10_IN_RANGE_GPIO1            BIT(1)
+#define AXP20X_GPIO10_IN_RANGE_GPIO0_VAL(x)     ((x) & BIT(0))
+#define AXP20X_GPIO10_IN_RANGE_GPIO1_VAL(x)     (((x) & BIT(0)) << 1)
+
+#define AXP20X_ADC_RATE_MASK                    GENMASK(7, 6)
+#define AXP20X_ADC_RATE_HZ(x)                   ((ilog2((x) / 25) << 6) & AXP20X_ADC_RATE_MASK)
+#define AXP22X_ADC_RATE_HZ(x)                   ((ilog2((x) / 100) << 6) & AXP20X_ADC_RATE_MASK)
+
+#define AXP20X_ADC_CHANNEL(_channel, _name, _type, _reg)        \
+        {                                                       \
+                .type = _type,                                  \
+                .indexed = 1,                                   \
+                .channel = _channel,                            \
+                .address = _reg,                                \
+                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |  \
+                                      BIT(IIO_CHAN_INFO_SCALE), \
+                .datasheet_name = _name,                        \
+        }
+
+#define AXP20X_ADC_CHANNEL_OFFSET(_channel, _name, _type, _reg) \
+        {                                                       \
+                .type = _type,                                  \
+                .indexed = 1,                                   \
+                .channel = _channel,                            \
+                .address = _reg,                                \
+                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |  \
+                                      BIT(IIO_CHAN_INFO_SCALE) |\
+                                      BIT(IIO_CHAN_INFO_OFFSET),\
+                .datasheet_name = _name,                        \
+        }
+
+struct axp_data;
+
+struct axp20x_adc_iio {
+        struct regmap           *regmap;
+        struct axp_data         *data;
+};
+
+enum axp20x_adc_channel_v {
+        AXP20X_ACIN_V = 0,
+        AXP20X_VBUS_V,
+        AXP20X_TS_IN,
+        AXP20X_GPIO0_V,
+        AXP20X_GPIO1_V,
+        AXP20X_IPSOUT_V,
+        AXP20X_BATT_V,
+};
+
+enum axp20x_adc_channel_i {
+        AXP20X_ACIN_I = 0,
+        AXP20X_VBUS_I,
+        AXP20X_BATT_CHRG_I,
+        AXP20X_BATT_DISCHRG_I,
+};
+
+enum axp22x_adc_channel_v {
+        AXP22X_TS_IN = 0,
+        AXP22X_BATT_V,
+};
+
+enum axp22x_adc_channel_i {
+        AXP22X_BATT_CHRG_I = 1,
+        AXP22X_BATT_DISCHRG_I,
+};
+
+static struct iio_map axp20x_maps[] = {
+        {
+                .consumer_dev_name = "axp20x-usb-power-supply",
+                .consumer_channel = "vbus_v",
+                .adc_channel_label = "vbus_v",
+        }, {
+                .consumer_dev_name = "axp20x-usb-power-supply",
+                .consumer_channel = "vbus_i",
+                .adc_channel_label = "vbus_i",
+        }, {
+                .consumer_dev_name = "axp20x-ac-power-supply",
+                .consumer_channel = "acin_v",
+                .adc_channel_label = "acin_v",
+        }, {
+                .consumer_dev_name = "axp20x-ac-power-supply",
+                .consumer_channel = "acin_i",
+                .adc_channel_label = "acin_i",
+        }, {
+                .consumer_dev_name = "axp20x-battery-power-supply",
+                .consumer_channel = "batt_v",
+                .adc_channel_label = "batt_v",
+        }, {
+                .consumer_dev_name = "axp20x-battery-power-supply",
+                .consumer_channel = "batt_chrg_i",
+                .adc_channel_label = "batt_chrg_i",
+        }, {
+                .consumer_dev_name = "axp20x-battery-power-supply",
+                .consumer_channel = "batt_dischrg_i",
+                .adc_channel_label = "batt_dischrg_i",
+        }, { /* sentinel */ }
+};
+
+static struct iio_map axp22x_maps[] = {
+        {
+                .consumer_dev_name = "axp20x-battery-power-supply",
+                .consumer_channel = "batt_v",
+                .adc_channel_label = "batt_v",
+        }, {
+                .consumer_dev_name = "axp20x-battery-power-supply",
+                .consumer_channel = "batt_chrg_i",
+                .adc_channel_label = "batt_chrg_i",
+        }, {
+                .consumer_dev_name = "axp20x-battery-power-supply",
+                .consumer_channel = "batt_dischrg_i",
+                .adc_channel_label = "batt_dischrg_i",
+        }, { /* sentinel */ }
+};
+
+/*
+ * Channels are mapped by physical system. Their channels share the same index.
+ * i.e. acin_i is in_current0_raw and acin_v is in_voltage0_raw.
+ * The only exception is for the battery. batt_v will be in_voltage6_raw and
+ * charge current in_current6_raw and discharge current will be in_current7_raw.
+ */
+static const struct iio_chan_spec axp20x_adc_channels[] = {
+        AXP20X_ADC_CHANNEL(AXP20X_ACIN_V, "acin_v", IIO_VOLTAGE,
+                           AXP20X_ACIN_V_ADC_H),
+        AXP20X_ADC_CHANNEL(AXP20X_ACIN_I, "acin_i", IIO_CURRENT,
+                           AXP20X_ACIN_I_ADC_H),
+        AXP20X_ADC_CHANNEL(AXP20X_VBUS_V, "vbus_v", IIO_VOLTAGE,
+                           AXP20X_VBUS_V_ADC_H),
+        AXP20X_ADC_CHANNEL(AXP20X_VBUS_I, "vbus_i", IIO_CURRENT,
+                           AXP20X_VBUS_I_ADC_H),
+        {
+                .type = IIO_TEMP,
+                .address = AXP20X_TEMP_ADC_H,
+                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+                                      BIT(IIO_CHAN_INFO_SCALE) |
+                                      BIT(IIO_CHAN_INFO_OFFSET),
+                .datasheet_name = "pmic_temp",
+        },
+        AXP20X_ADC_CHANNEL_OFFSET(AXP20X_GPIO0_V, "gpio0_v", IIO_VOLTAGE,
+                                  AXP20X_GPIO0_V_ADC_H),
+        AXP20X_ADC_CHANNEL_OFFSET(AXP20X_GPIO1_V, "gpio1_v", IIO_VOLTAGE,
+                                  AXP20X_GPIO1_V_ADC_H),
+        AXP20X_ADC_CHANNEL(AXP20X_IPSOUT_V, "ipsout_v", IIO_VOLTAGE,
+                           AXP20X_IPSOUT_V_HIGH_H),
+        AXP20X_ADC_CHANNEL(AXP20X_BATT_V, "batt_v", IIO_VOLTAGE,
+                           AXP20X_BATT_V_H),
+        AXP20X_ADC_CHANNEL(AXP20X_BATT_CHRG_I, "batt_chrg_i", IIO_CURRENT,
+                           AXP20X_BATT_CHRG_I_H),
+        AXP20X_ADC_CHANNEL(AXP20X_BATT_DISCHRG_I, "batt_dischrg_i", IIO_CURRENT,
+                           AXP20X_BATT_DISCHRG_I_H),
+};
+
+static const struct iio_chan_spec axp22x_adc_channels[] = {
+        {
+                .type = IIO_TEMP,
+                .address = AXP22X_PMIC_TEMP_H,
+                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+                                      BIT(IIO_CHAN_INFO_SCALE) |
+                                      BIT(IIO_CHAN_INFO_OFFSET),
+                .datasheet_name = "pmic_temp",
+        },
+        AXP20X_ADC_CHANNEL(AXP22X_BATT_V, "batt_v", IIO_VOLTAGE,
+                           AXP20X_BATT_V_H),
+        AXP20X_ADC_CHANNEL(AXP22X_BATT_CHRG_I, "batt_chrg_i", IIO_CURRENT,
+                           AXP20X_BATT_CHRG_I_H),
+        AXP20X_ADC_CHANNEL(AXP22X_BATT_DISCHRG_I, "batt_dischrg_i", IIO_CURRENT,
+                           AXP20X_BATT_DISCHRG_I_H),
+};
+
+static int axp20x_adc_raw(struct iio_dev *indio_dev,
+                          struct iio_chan_spec const *chan, int *val)
+{
+        struct axp20x_adc_iio *info = iio_priv(indio_dev);
+        int size = 12;
+
+        /*
+         * N.B.:  Unlike the Chinese datasheets tell, the charging current is
+         * stored on 12 bits, not 13 bits. Only discharging current is on 13
+         * bits.
+         */
+        if (chan->type == IIO_CURRENT && chan->channel == AXP20X_BATT_DISCHRG_I)
+                size = 13;
+        else
+                size = 12;
+
+        *val = axp20x_read_variable_width(info->regmap, chan->address, size);
+        if (*val < 0)
+                return *val;
+
+        return IIO_VAL_INT;
+}
+
+static int axp22x_adc_raw(struct iio_dev *indio_dev,
+                          struct iio_chan_spec const *chan, int *val)
+{
+        struct axp20x_adc_iio *info = iio_priv(indio_dev);
+        int size;
+
+        /*
+         * N.B.: Unlike the Chinese datasheets tell, the charging current is
+         * stored on 12 bits, not 13 bits. Only discharging current is on 13
+         * bits.
+         */
+        if (chan->type == IIO_CURRENT && chan->channel == AXP22X_BATT_DISCHRG_I)
+                size = 13;
+        else
+                size = 12;
+
+        *val = axp20x_read_variable_width(info->regmap, chan->address, size);
+        if (*val < 0)
+                return *val;
+
+        return IIO_VAL_INT;
+}
+
+static int axp20x_adc_scale_voltage(int channel, int *val, int *val2)
+{
+        switch (channel) {
+        case AXP20X_ACIN_V:
+        case AXP20X_VBUS_V:
+                *val = 1;
+                *val2 = 700000;
+                return IIO_VAL_INT_PLUS_MICRO;
+
+        case AXP20X_GPIO0_V:
+        case AXP20X_GPIO1_V:
+                *val = 0;
+                *val2 = 500000;
+                return IIO_VAL_INT_PLUS_MICRO;
+
+        case AXP20X_BATT_V:
+                *val = 1;
+                *val2 = 100000;
+                return IIO_VAL_INT_PLUS_MICRO;
+
+        case AXP20X_IPSOUT_V:
+                *val = 1;
+                *val2 = 400000;
+                return IIO_VAL_INT_PLUS_MICRO;
+
+        default:
+                return -EINVAL;
+        }
+}
+
+static int axp20x_adc_scale_current(int channel, int *val, int *val2)
+{
+        switch (channel) {
+        case AXP20X_ACIN_I:
+                *val = 0;
+                *val2 = 625000;
+                return IIO_VAL_INT_PLUS_MICRO;
+
+        case AXP20X_VBUS_I:
+                *val = 0;
+                *val2 = 375000;
+                return IIO_VAL_INT_PLUS_MICRO;
+
+        case AXP20X_BATT_DISCHRG_I:
+        case AXP20X_BATT_CHRG_I:
+                *val = 0;
+                *val2 = 500000;
+                return IIO_VAL_INT_PLUS_MICRO;
+
+        default:
+                return -EINVAL;
+        }
+}
+
+static int axp20x_adc_scale(struct iio_chan_spec const *chan, int *val,
+                            int *val2)
+{
+        switch (chan->type) {
+        case IIO_VOLTAGE:
+                return axp20x_adc_scale_voltage(chan->channel, val, val2);
+
+        case IIO_CURRENT:
+                return axp20x_adc_scale_current(chan->channel, val, val2);
+
+        case IIO_TEMP:
+                *val = 100;
+                return IIO_VAL_INT;
+
+        default:
+                return -EINVAL;
+        }
+}
+
+static int axp22x_adc_scale(struct iio_chan_spec const *chan, int *val,
+                            int *val2)
+{
+        switch (chan->type) {
+        case IIO_VOLTAGE:
+                if (chan->channel != AXP22X_BATT_V)
+                        return -EINVAL;
+
+                *val = 1;
+                *val2 = 100000;
+                return IIO_VAL_INT_PLUS_MICRO;
+
+        case IIO_CURRENT:
+                *val = 0;
+                *val2 = 500000;
+                return IIO_VAL_INT_PLUS_MICRO;
+
+        case IIO_TEMP:
+                *val = 100;
+                return IIO_VAL_INT;
+
+        default:
+                return -EINVAL;
+        }
+}
+
+static int axp20x_adc_offset_voltage(struct iio_dev *indio_dev, int channel,
+                                     int *val)
+{
+        struct axp20x_adc_iio *info = iio_priv(indio_dev);
+        int ret;
+
+        ret = regmap_read(info->regmap, AXP20X_GPIO10_IN_RANGE, val);
+        if (ret < 0)
+                return ret;
+
+        switch (channel) {
+        case AXP20X_GPIO0_V:
+                *val &= AXP20X_GPIO10_IN_RANGE_GPIO0;
+                break;
+
+        case AXP20X_GPIO1_V:
+                *val &= AXP20X_GPIO10_IN_RANGE_GPIO1;
+                break;
+
+        default:
+                return -EINVAL;
+        }
+
+        *val = !!(*val) * 700000;
+
+        return IIO_VAL_INT;
+}
+
+static int axp20x_adc_offset(struct iio_dev *indio_dev,
+                             struct iio_chan_spec const *chan, int *val)
+{
+        switch (chan->type) {
+        case IIO_VOLTAGE:
+                return axp20x_adc_offset_voltage(indio_dev, chan->channel, val);
+
+        case IIO_TEMP:
+                *val = -1447;
+                return IIO_VAL_INT;
+
+        default:
+                return -EINVAL;
+        }
+}
+
+static int axp20x_read_raw(struct iio_dev *indio_dev,
+                           struct iio_chan_spec const *chan, int *val,
+                           int *val2, long mask)
+{
+        switch (mask) {
+        case IIO_CHAN_INFO_OFFSET:
+                return axp20x_adc_offset(indio_dev, chan, val);
+
+        case IIO_CHAN_INFO_SCALE:
+                return axp20x_adc_scale(chan, val, val2);
+
+        case IIO_CHAN_INFO_RAW:
+                return axp20x_adc_raw(indio_dev, chan, val);
+
+        default:
+                return -EINVAL;
+        }
+}
+
+static int axp22x_read_raw(struct iio_dev *indio_dev,
+                           struct iio_chan_spec const *chan, int *val,
+                           int *val2, long mask)
+{
+        switch (mask) {
+        case IIO_CHAN_INFO_OFFSET:
+                *val = -2677;
+                return IIO_VAL_INT;
+
+        case IIO_CHAN_INFO_SCALE:
+                return axp22x_adc_scale(chan, val, val2);
+
+        case IIO_CHAN_INFO_RAW:
+                return axp22x_adc_raw(indio_dev, chan, val);
+
+        default:
+                return -EINVAL;
+        }
+}
+
+static int axp20x_write_raw(struct iio_dev *indio_dev,
+                            struct iio_chan_spec const *chan, int val, int val2,
+                            long mask)
+{
+        struct axp20x_adc_iio *info = iio_priv(indio_dev);
+        unsigned int reg, regval;
+
+        /*
+         * The AXP20X PMIC allows the user to choose between 0V and 0.7V offsets
+         * for (independently) GPIO0 and GPIO1 when in ADC mode.
+         */
+        if (mask != IIO_CHAN_INFO_OFFSET)
+                return -EINVAL;
+
+        if (val != 0 && val != 700000)
+                return -EINVAL;
+
+        switch (chan->channel) {
+        case AXP20X_GPIO0_V:
+                reg = AXP20X_GPIO10_IN_RANGE_GPIO0;
+                regval = AXP20X_GPIO10_IN_RANGE_GPIO0_VAL(!!val);
+                break;
+
+        case AXP20X_GPIO1_V:
+                reg = AXP20X_GPIO10_IN_RANGE_GPIO1;
+                regval = AXP20X_GPIO10_IN_RANGE_GPIO1_VAL(!!val);
+                break;
+
+        default:
+                return -EINVAL;
+        }
+
+        return regmap_update_bits(info->regmap, AXP20X_GPIO10_IN_RANGE, reg,
+                                  regval);
+}
+
+static const struct iio_info axp20x_adc_iio_info = {
+        .read_raw = axp20x_read_raw,
+        .write_raw = axp20x_write_raw,
+        .driver_module = THIS_MODULE,
+};
+
+static const struct iio_info axp22x_adc_iio_info = {
+        .read_raw = axp22x_read_raw,
+        .driver_module = THIS_MODULE,
+};
+
+static int axp20x_adc_rate(int rate)
+{
+        return AXP20X_ADC_RATE_HZ(rate);
+}
+
+static int axp22x_adc_rate(int rate)
+{
+        return AXP22X_ADC_RATE_HZ(rate);
+}
+
+struct axp_data {
+        const struct iio_info           *iio_info;
+        int                             num_channels;
+        struct iio_chan_spec const      *channels;
+        unsigned long                   adc_en1_mask;
+        int                             (*adc_rate)(int rate);
+        bool                            adc_en2;
+        struct iio_map                  *maps;
+};
+
+static const struct axp_data axp20x_data = {
+        .iio_info = &axp20x_adc_iio_info,
+        .num_channels = ARRAY_SIZE(axp20x_adc_channels),
+        .channels = axp20x_adc_channels,
+        .adc_en1_mask = AXP20X_ADC_EN1_MASK,
+        .adc_rate = axp20x_adc_rate,
+        .adc_en2 = true,
+        .maps = axp20x_maps,
+};
+
+static const struct axp_data axp22x_data = {
+        .iio_info = &axp22x_adc_iio_info,
+        .num_channels = ARRAY_SIZE(axp22x_adc_channels),
+        .channels = axp22x_adc_channels,
+        .adc_en1_mask = AXP22X_ADC_EN1_MASK,
+        .adc_rate = axp22x_adc_rate,
+        .adc_en2 = false,
+        .maps = axp22x_maps,
+};
+
+static const struct platform_device_id axp20x_adc_id_match[] = {
+        { .name = "axp20x-adc", .driver_data = (kernel_ulong_t)&axp20x_data, },
+        { .name = "axp22x-adc", .driver_data = (kernel_ulong_t)&axp22x_data, },
+        { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(platform, axp20x_adc_id_match);
+
+static int axp20x_probe(struct platform_device *pdev)
+{
+        struct axp20x_adc_iio *info;
+        struct iio_dev *indio_dev;
+        struct axp20x_dev *axp20x_dev;
+        int ret;
+
+        axp20x_dev = dev_get_drvdata(pdev->dev.parent);
+
+        indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info));
+        if (!indio_dev)
+                return -ENOMEM;
+
+        info = iio_priv(indio_dev);
+        platform_set_drvdata(pdev, indio_dev);
+
+        info->regmap = axp20x_dev->regmap;
+        indio_dev->dev.parent = &pdev->dev;
+        indio_dev->dev.of_node = pdev->dev.of_node;
+        indio_dev->modes = INDIO_DIRECT_MODE;
+
+        info->data = (struct axp_data *)platform_get_device_id(pdev)->driver_data;
+
+        indio_dev->name = platform_get_device_id(pdev)->name;
+        indio_dev->info = info->data->iio_info;
+        indio_dev->num_channels = info->data->num_channels;
+        indio_dev->channels = info->data->channels;
+
+        /* Enable the ADCs on IP */
+        regmap_write(info->regmap, AXP20X_ADC_EN1, info->data->adc_en1_mask);
+
+        if (info->data->adc_en2)
+                /* Enable GPIO0/1 and internal temperature ADCs */
+                regmap_update_bits(info->regmap, AXP20X_ADC_EN2,
+                                   AXP20X_ADC_EN2_MASK, AXP20X_ADC_EN2_MASK);
+
+        /* Configure ADCs rate */
+        regmap_update_bits(info->regmap, AXP20X_ADC_RATE, AXP20X_ADC_RATE_MASK,
+                           info->data->adc_rate(100));
+
+        ret = iio_map_array_register(indio_dev, info->data->maps);
+        if (ret < 0) {
+                dev_err(&pdev->dev, "failed to register IIO maps: %d\n", ret);
+                goto fail_map;
+        }
+
+        ret = iio_device_register(indio_dev);
+        if (ret < 0) {
+                dev_err(&pdev->dev, "could not register the device\n");
+                goto fail_register;
+        }
+
+        return 0;
+
+fail_register:
+        iio_map_array_unregister(indio_dev);
+
+fail_map:
+        regmap_write(info->regmap, AXP20X_ADC_EN1, 0);
+
+        if (info->data->adc_en2)
+                regmap_write(info->regmap, AXP20X_ADC_EN2, 0);
+
+        return ret;
+}
+
+static int axp20x_remove(struct platform_device *pdev)
+{
+        struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+        struct axp20x_adc_iio *info = iio_priv(indio_dev);
+
+        iio_device_unregister(indio_dev);
+        iio_map_array_unregister(indio_dev);
+
+        regmap_write(info->regmap, AXP20X_ADC_EN1, 0);
+
+        if (info->data->adc_en2)
+                regmap_write(info->regmap, AXP20X_ADC_EN2, 0);
+
+        return 0;
+}
+
+static struct platform_driver axp20x_adc_driver = {
+        .driver = {
+                .name = "axp20x-adc",
+        },
+        .id_table = axp20x_adc_id_match,
+        .probe = axp20x_probe,
+        .remove = axp20x_remove,
+};
+
+module_platform_driver(axp20x_adc_driver);
+
+MODULE_DESCRIPTION("ADC driver for AXP20X and AXP22X PMICs");
+MODULE_AUTHOR("Quentin Schulz <quentin.schulz@free-electrons.com>");
+MODULE_LICENSE("GPL");