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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * axp288_adc.c - X-Powers AXP288 PMIC ADC Driver4 *5 * Copyright (C) 2014 Intel Corporation6 *7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~8 */9 10#include <linux/dmi.h>11#include <linux/module.h>12#include <linux/mutex.h>13#include <linux/kernel.h>14#include <linux/device.h>15#include <linux/regmap.h>16#include <linux/mfd/axp20x.h>17#include <linux/platform_device.h>18 19#include <linux/iio/iio.h>20#include <linux/iio/machine.h>21#include <linux/iio/driver.h>22 23/*24 * This mask enables all ADCs except for the battery temp-sensor (TS), that is25 * left as-is to avoid breaking charging on devices without a temp-sensor.26 */27#define AXP288_ADC_EN_MASK 0xF028#define AXP288_ADC_TS_ENABLE 0x0129 30#define AXP288_ADC_TS_BIAS_MASK GENMASK(5, 4)31#define AXP288_ADC_TS_BIAS_20UA (0 << 4)32#define AXP288_ADC_TS_BIAS_40UA (1 << 4)33#define AXP288_ADC_TS_BIAS_60UA (2 << 4)34#define AXP288_ADC_TS_BIAS_80UA (3 << 4)35#define AXP288_ADC_TS_CURRENT_ON_OFF_MASK GENMASK(1, 0)36#define AXP288_ADC_TS_CURRENT_OFF (0 << 0)37#define AXP288_ADC_TS_CURRENT_ON_WHEN_CHARGING (1 << 0)38#define AXP288_ADC_TS_CURRENT_ON_ONDEMAND (2 << 0)39#define AXP288_ADC_TS_CURRENT_ON (3 << 0)40 41enum axp288_adc_id {42 AXP288_ADC_TS,43 AXP288_ADC_PMIC,44 AXP288_ADC_GP,45 AXP288_ADC_BATT_CHRG_I,46 AXP288_ADC_BATT_DISCHRG_I,47 AXP288_ADC_BATT_V,48 AXP288_ADC_NR_CHAN,49};50 51struct axp288_adc_info {52 int irq;53 struct regmap *regmap;54 /* lock to protect against multiple access to the device */55 struct mutex lock;56 bool ts_enabled;57};58 59static const struct iio_chan_spec axp288_adc_channels[] = {60 {61 .indexed = 1,62 .type = IIO_TEMP,63 .channel = 0,64 .address = AXP288_TS_ADC_H,65 .datasheet_name = "TS_PIN",66 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),67 }, {68 .indexed = 1,69 .type = IIO_TEMP,70 .channel = 1,71 .address = AXP288_PMIC_ADC_H,72 .datasheet_name = "PMIC_TEMP",73 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),74 }, {75 .indexed = 1,76 .type = IIO_TEMP,77 .channel = 2,78 .address = AXP288_GP_ADC_H,79 .datasheet_name = "GPADC",80 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),81 }, {82 .indexed = 1,83 .type = IIO_CURRENT,84 .channel = 3,85 .address = AXP20X_BATT_CHRG_I_H,86 .datasheet_name = "BATT_CHG_I",87 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),88 }, {89 .indexed = 1,90 .type = IIO_CURRENT,91 .channel = 4,92 .address = AXP20X_BATT_DISCHRG_I_H,93 .datasheet_name = "BATT_DISCHRG_I",94 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),95 }, {96 .indexed = 1,97 .type = IIO_VOLTAGE,98 .channel = 5,99 .address = AXP20X_BATT_V_H,100 .datasheet_name = "BATT_V",101 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),102 },103};104 105/* for consumer drivers */106static struct iio_map axp288_adc_default_maps[] = {107 IIO_MAP("TS_PIN", "axp288-batt", "axp288-batt-temp"),108 IIO_MAP("PMIC_TEMP", "axp288-pmic", "axp288-pmic-temp"),109 IIO_MAP("GPADC", "axp288-gpadc", "axp288-system-temp"),110 IIO_MAP("BATT_CHG_I", "axp288-chrg", "axp288-chrg-curr"),111 IIO_MAP("BATT_DISCHRG_I", "axp288-chrg", "axp288-chrg-d-curr"),112 IIO_MAP("BATT_V", "axp288-batt", "axp288-batt-volt"),113 {},114};115 116static int axp288_adc_read_channel(int *val, unsigned long address,117 struct regmap *regmap)118{119 u8 buf[2];120 121 if (regmap_bulk_read(regmap, address, buf, 2))122 return -EIO;123 *val = (buf[0] << 4) + ((buf[1] >> 4) & 0x0F);124 125 return IIO_VAL_INT;126}127 128/*129 * The current-source used for the battery temp-sensor (TS) is shared130 * with the GPADC. For proper fuel-gauge and charger operation the TS131 * current-source needs to be permanently on. But to read the GPADC we132 * need to temporary switch the TS current-source to ondemand, so that133 * the GPADC can use it, otherwise we will always read an all 0 value.134 */135static int axp288_adc_set_ts(struct axp288_adc_info *info,136 unsigned int mode, unsigned long address)137{138 int ret;139 140 /* No need to switch the current-source if the TS pin is disabled */141 if (!info->ts_enabled)142 return 0;143 144 /* Channels other than GPADC do not need the current source */145 if (address != AXP288_GP_ADC_H)146 return 0;147 148 ret = regmap_update_bits(info->regmap, AXP288_ADC_TS_PIN_CTRL,149 AXP288_ADC_TS_CURRENT_ON_OFF_MASK, mode);150 if (ret)151 return ret;152 153 /* When switching to the GPADC pin give things some time to settle */154 if (mode == AXP288_ADC_TS_CURRENT_ON_ONDEMAND)155 usleep_range(6000, 10000);156 157 return 0;158}159 160static int axp288_adc_read_raw(struct iio_dev *indio_dev,161 struct iio_chan_spec const *chan,162 int *val, int *val2, long mask)163{164 int ret;165 struct axp288_adc_info *info = iio_priv(indio_dev);166 167 mutex_lock(&info->lock);168 switch (mask) {169 case IIO_CHAN_INFO_RAW:170 if (axp288_adc_set_ts(info, AXP288_ADC_TS_CURRENT_ON_ONDEMAND,171 chan->address)) {172 dev_err(&indio_dev->dev, "GPADC mode\n");173 ret = -EINVAL;174 break;175 }176 ret = axp288_adc_read_channel(val, chan->address, info->regmap);177 if (axp288_adc_set_ts(info, AXP288_ADC_TS_CURRENT_ON,178 chan->address))179 dev_err(&indio_dev->dev, "TS pin restore\n");180 break;181 default:182 ret = -EINVAL;183 }184 mutex_unlock(&info->lock);185 186 return ret;187}188 189/*190 * We rely on the machine's firmware to correctly setup the TS pin bias current191 * at boot. This lists systems with broken fw where we need to set it ourselves.192 */193static const struct dmi_system_id axp288_adc_ts_bias_override[] = {194 {195 /* Lenovo Ideapad 100S (11 inch) */196 .matches = {197 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),198 DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo ideapad 100S-11IBY"),199 },200 .driver_data = (void *)(uintptr_t)AXP288_ADC_TS_BIAS_80UA,201 },202 {203 /* Nuvision Solo 10 Draw */204 .matches = {205 DMI_MATCH(DMI_SYS_VENDOR, "TMAX"),206 DMI_MATCH(DMI_PRODUCT_NAME, "TM101W610L"),207 },208 .driver_data = (void *)(uintptr_t)AXP288_ADC_TS_BIAS_80UA,209 },210 {}211};212 213static int axp288_adc_initialize(struct axp288_adc_info *info)214{215 const struct dmi_system_id *bias_override;216 int ret, adc_enable_val;217 218 bias_override = dmi_first_match(axp288_adc_ts_bias_override);219 if (bias_override) {220 ret = regmap_update_bits(info->regmap, AXP288_ADC_TS_PIN_CTRL,221 AXP288_ADC_TS_BIAS_MASK,222 (uintptr_t)bias_override->driver_data);223 if (ret)224 return ret;225 }226 227 /*228 * Determine if the TS pin is enabled and set the TS current-source229 * accordingly.230 */231 ret = regmap_read(info->regmap, AXP20X_ADC_EN1, &adc_enable_val);232 if (ret)233 return ret;234 235 if (adc_enable_val & AXP288_ADC_TS_ENABLE) {236 info->ts_enabled = true;237 ret = regmap_update_bits(info->regmap, AXP288_ADC_TS_PIN_CTRL,238 AXP288_ADC_TS_CURRENT_ON_OFF_MASK,239 AXP288_ADC_TS_CURRENT_ON);240 } else {241 info->ts_enabled = false;242 ret = regmap_update_bits(info->regmap, AXP288_ADC_TS_PIN_CTRL,243 AXP288_ADC_TS_CURRENT_ON_OFF_MASK,244 AXP288_ADC_TS_CURRENT_OFF);245 }246 if (ret)247 return ret;248 249 /* Turn on the ADC for all channels except TS, leave TS as is */250 return regmap_set_bits(info->regmap, AXP20X_ADC_EN1,251 AXP288_ADC_EN_MASK);252}253 254static const struct iio_info axp288_adc_iio_info = {255 .read_raw = &axp288_adc_read_raw,256};257 258static int axp288_adc_probe(struct platform_device *pdev)259{260 int ret;261 struct axp288_adc_info *info;262 struct iio_dev *indio_dev;263 struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);264 265 indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info));266 if (!indio_dev)267 return -ENOMEM;268 269 info = iio_priv(indio_dev);270 info->irq = platform_get_irq(pdev, 0);271 if (info->irq < 0)272 return info->irq;273 274 info->regmap = axp20x->regmap;275 /*276 * Set ADC to enabled state at all time, including system suspend.277 * otherwise internal fuel gauge functionality may be affected.278 */279 ret = axp288_adc_initialize(info);280 if (ret) {281 dev_err(&pdev->dev, "unable to enable ADC device\n");282 return ret;283 }284 285 indio_dev->name = pdev->name;286 indio_dev->channels = axp288_adc_channels;287 indio_dev->num_channels = ARRAY_SIZE(axp288_adc_channels);288 indio_dev->info = &axp288_adc_iio_info;289 indio_dev->modes = INDIO_DIRECT_MODE;290 291 ret = devm_iio_map_array_register(&pdev->dev, indio_dev, axp288_adc_default_maps);292 if (ret < 0)293 return ret;294 295 mutex_init(&info->lock);296 297 return devm_iio_device_register(&pdev->dev, indio_dev);298}299 300static const struct platform_device_id axp288_adc_id_table[] = {301 { .name = "axp288_adc" },302 { }303};304 305static struct platform_driver axp288_adc_driver = {306 .probe = axp288_adc_probe,307 .id_table = axp288_adc_id_table,308 .driver = {309 .name = "axp288_adc",310 },311};312 313MODULE_DEVICE_TABLE(platform, axp288_adc_id_table);314 315module_platform_driver(axp288_adc_driver);316 317MODULE_AUTHOR("Jacob Pan <jacob.jun.pan@linux.intel.com>");318MODULE_DESCRIPTION("X-Powers AXP288 ADC Driver");319MODULE_LICENSE("GPL");320