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authorQuentin Schulz <quentin.schulz@free-electrons.com>2017-04-04 08:34:41 +0200
committerLee Jones <lee.jones@linaro.org>2017-04-27 09:25:07 +0100
commit0e34d5de961d5a8a84cf77878ca871c6e8104620 (patch)
treeab1eb178d67f1320548b0530cae31743daad27a9 /drivers/iio/adc/axp20x_adc.c
parentbe269180c9335c257a2763c3fd3a44e65c90c1f0 (diff)
downloadlinux-0e34d5de961d5a8a84cf77878ca871c6e8104620.tar.bz2
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>
Diffstat (limited to 'drivers/iio/adc/axp20x_adc.c')
-rw-r--r--drivers/iio/adc/axp20x_adc.c617
1 files changed, 617 insertions, 0 deletions
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");