--- /dev/null
+/*
+ * axp288_adc.c - X-Powers AXP288 PMIC ADC Driver
+ *
+ * Copyright (C) 2014 Intel Corporation
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/regmap.h>
+#include <linux/mfd/axp20x.h>
+#include <linux/platform_device.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/machine.h>
+#include <linux/iio/driver.h>
+
+#define AXP288_ADC_EN_MASK 0xF1
+#define AXP288_ADC_TS_PIN_GPADC 0xF2
+#define AXP288_ADC_TS_PIN_ON 0xF3
+
+enum axp288_adc_id {
+ AXP288_ADC_TS,
+ AXP288_ADC_PMIC,
+ AXP288_ADC_GP,
+ AXP288_ADC_BATT_CHRG_I,
+ AXP288_ADC_BATT_DISCHRG_I,
+ AXP288_ADC_BATT_V,
+ AXP288_ADC_NR_CHAN,
+};
+
+struct axp288_adc_info {
+ int irq;
+ struct regmap *regmap;
+};
+
+static const struct iio_chan_spec const axp288_adc_channels[] = {
+ {
+ .indexed = 1,
+ .type = IIO_TEMP,
+ .channel = 0,
+ .address = AXP288_TS_ADC_H,
+ .datasheet_name = "TS_PIN",
+ }, {
+ .indexed = 1,
+ .type = IIO_TEMP,
+ .channel = 1,
+ .address = AXP288_PMIC_ADC_H,
+ .datasheet_name = "PMIC_TEMP",
+ }, {
+ .indexed = 1,
+ .type = IIO_TEMP,
+ .channel = 2,
+ .address = AXP288_GP_ADC_H,
+ .datasheet_name = "GPADC",
+ }, {
+ .indexed = 1,
+ .type = IIO_CURRENT,
+ .channel = 3,
+ .address = AXP20X_BATT_CHRG_I_H,
+ .datasheet_name = "BATT_CHG_I",
+ .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
+ }, {
+ .indexed = 1,
+ .type = IIO_CURRENT,
+ .channel = 4,
+ .address = AXP20X_BATT_DISCHRG_I_H,
+ .datasheet_name = "BATT_DISCHRG_I",
+ .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
+ }, {
+ .indexed = 1,
+ .type = IIO_VOLTAGE,
+ .channel = 5,
+ .address = AXP20X_BATT_V_H,
+ .datasheet_name = "BATT_V",
+ .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
+ },
+};
+
+#define AXP288_ADC_MAP(_adc_channel_label, _consumer_dev_name, \
+ _consumer_channel) \
+ { \
+ .adc_channel_label = _adc_channel_label, \
+ .consumer_dev_name = _consumer_dev_name, \
+ .consumer_channel = _consumer_channel, \
+ }
+
+/* for consumer drivers */
+static struct iio_map axp288_adc_default_maps[] = {
+ AXP288_ADC_MAP("TS_PIN", "axp288-batt", "axp288-batt-temp"),
+ AXP288_ADC_MAP("PMIC_TEMP", "axp288-pmic", "axp288-pmic-temp"),
+ AXP288_ADC_MAP("GPADC", "axp288-gpadc", "axp288-system-temp"),
+ AXP288_ADC_MAP("BATT_CHG_I", "axp288-chrg", "axp288-chrg-curr"),
+ AXP288_ADC_MAP("BATT_DISCHRG_I", "axp288-chrg", "axp288-chrg-d-curr"),
+ AXP288_ADC_MAP("BATT_V", "axp288-batt", "axp288-batt-volt"),
+ {},
+};
+
+static int axp288_adc_read_channel(int *val, unsigned long address,
+ struct regmap *regmap)
+{
+ u8 buf[2];
+
+ if (regmap_bulk_read(regmap, address, buf, 2))
+ return -EIO;
+ *val = (buf[0] << 4) + ((buf[1] >> 4) & 0x0F);
+
+ return IIO_VAL_INT;
+}
+
+static int axp288_adc_set_ts(struct regmap *regmap, unsigned int mode,
+ unsigned long address)
+{
+ /* channels other than GPADC do not need to switch TS pin */
+ if (address != AXP288_GP_ADC_H)
+ return 0;
+
+ return regmap_write(regmap, AXP288_ADC_TS_PIN_CTRL, mode);
+}
+
+static int axp288_adc_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ int ret;
+ struct axp288_adc_info *info = iio_priv(indio_dev);
+
+ mutex_lock(&indio_dev->mlock);
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ if (axp288_adc_set_ts(info->regmap, AXP288_ADC_TS_PIN_GPADC,
+ chan->address)) {
+ dev_err(&indio_dev->dev, "GPADC mode\n");
+ ret = -EINVAL;
+ break;
+ }
+ ret = axp288_adc_read_channel(val, chan->address, info->regmap);
+ if (axp288_adc_set_ts(info->regmap, AXP288_ADC_TS_PIN_ON,
+ chan->address))
+ dev_err(&indio_dev->dev, "TS pin restore\n");
+ break;
+ case IIO_CHAN_INFO_PROCESSED:
+ ret = axp288_adc_read_channel(val, chan->address, info->regmap);
+ break;
+ default:
+ ret = -EINVAL;
+ }
+ mutex_unlock(&indio_dev->mlock);
+
+ return ret;
+}
+
+static int axp288_adc_set_state(struct regmap *regmap)
+{
+ /* ADC should be always enabled for internal FG to function */
+ if (regmap_write(regmap, AXP288_ADC_TS_PIN_CTRL, AXP288_ADC_TS_PIN_ON))
+ return -EIO;
+
+ return regmap_write(regmap, AXP20X_ADC_EN1, AXP288_ADC_EN_MASK);
+}
+
+static const struct iio_info axp288_adc_iio_info = {
+ .read_raw = &axp288_adc_read_raw,
+ .driver_module = THIS_MODULE,
+};
+
+static int axp288_adc_probe(struct platform_device *pdev)
+{
+ int ret;
+ struct axp288_adc_info *info;
+ struct iio_dev *indio_dev;
+ struct axp20x_dev *axp20x = 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);
+ info->irq = platform_get_irq(pdev, 0);
+ if (info->irq < 0) {
+ dev_err(&pdev->dev, "no irq resource?\n");
+ return info->irq;
+ }
+ platform_set_drvdata(pdev, indio_dev);
+ info->regmap = axp20x->regmap;
+ /*
+ * Set ADC to enabled state at all time, including system suspend.
+ * otherwise internal fuel gauge functionality may be affected.
+ */
+ ret = axp288_adc_set_state(axp20x->regmap);
+ if (ret) {
+ dev_err(&pdev->dev, "unable to enable ADC device\n");
+ return ret;
+ }
+
+ indio_dev->dev.parent = &pdev->dev;
+ indio_dev->name = pdev->name;
+ indio_dev->channels = axp288_adc_channels;
+ indio_dev->num_channels = ARRAY_SIZE(axp288_adc_channels);
+ indio_dev->info = &axp288_adc_iio_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ ret = iio_map_array_register(indio_dev, axp288_adc_default_maps);
+ if (ret < 0)
+ return ret;
+
+ ret = iio_device_register(indio_dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "unable to register iio device\n");
+ goto err_array_unregister;
+ }
+ return 0;
+
+err_array_unregister:
+ iio_map_array_unregister(indio_dev);
+
+ return ret;
+}
+
+static int axp288_adc_remove(struct platform_device *pdev)
+{
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+
+ iio_device_unregister(indio_dev);
+ iio_map_array_unregister(indio_dev);
+
+ return 0;
+}
+
+static struct platform_driver axp288_adc_driver = {
+ .probe = axp288_adc_probe,
+ .remove = axp288_adc_remove,
+ .driver = {
+ .name = "axp288_adc",
+ .owner = THIS_MODULE,
+ },
+};
+
+module_platform_driver(axp288_adc_driver);
+
+MODULE_AUTHOR("Jacob Pan <jacob.jun.pan@linux.intel.com>");
+MODULE_DESCRIPTION("X-Powers AXP288 ADC Driver");
+MODULE_LICENSE("GPL");