diff options
Diffstat (limited to 'drivers/iio/adc/axp288_adc.c')
| -rw-r--r-- | drivers/iio/adc/axp288_adc.c | 261 |
1 files changed, 261 insertions, 0 deletions
diff --git a/drivers/iio/adc/axp288_adc.c b/drivers/iio/adc/axp288_adc.c new file mode 100644 index 000000000000..08bcfb061ca5 --- /dev/null +++ b/drivers/iio/adc/axp288_adc.c @@ -0,0 +1,261 @@ +/* + * 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_device_id axp288_adc_id_table[] = { + { .name = "axp288_adc" }, + {}, +}; + +static struct platform_driver axp288_adc_driver = { + .probe = axp288_adc_probe, + .remove = axp288_adc_remove, + .id_table = axp288_adc_id_table, + .driver = { + .name = "axp288_adc", + }, +}; + +MODULE_DEVICE_TABLE(platform, axp288_adc_id_table); + +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"); |