diff options
Diffstat (limited to 'drivers/iio/adc/mt6370-adc.c')
| -rw-r--r-- | drivers/iio/adc/mt6370-adc.c | 305 |
1 files changed, 305 insertions, 0 deletions
diff --git a/drivers/iio/adc/mt6370-adc.c b/drivers/iio/adc/mt6370-adc.c new file mode 100644 index 000000000000..bc62e5a9d50d --- /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 <chiaen_wu@richtek.com> + */ + +#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, ®_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, ®_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 = 10; + 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_INT; + 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 <chiaen_wu@richtek.com>"); +MODULE_DESCRIPTION("MT6370 ADC Driver"); +MODULE_LICENSE("GPL v2"); |