1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * MP2629 Driver for ADC 4 * 5 * Copyright 2020 Monolithic Power Systems, Inc 6 * 7 * Author: Saravanan Sekar <sravanhome@gmail.com> 8 */ 9 10 #include <linux/iio/driver.h> 11 #include <linux/iio/iio.h> 12 #include <linux/iio/machine.h> 13 #include <linux/mfd/mp2629.h> 14 #include <linux/mod_devicetable.h> 15 #include <linux/module.h> 16 #include <linux/mutex.h> 17 #include <linux/platform_device.h> 18 #include <linux/regmap.h> 19 20 #define MP2629_REG_ADC_CTRL 0x03 21 #define MP2629_REG_BATT_VOLT 0x0e 22 #define MP2629_REG_SYSTEM_VOLT 0x0f 23 #define MP2629_REG_INPUT_VOLT 0x11 24 #define MP2629_REG_BATT_CURRENT 0x12 25 #define MP2629_REG_INPUT_CURRENT 0x13 26 27 #define MP2629_ADC_START BIT(7) 28 #define MP2629_ADC_CONTINUOUS BIT(6) 29 30 #define MP2629_MAP(_mp, _mpc) IIO_MAP(#_mp, "mp2629_charger", "mp2629-"_mpc) 31 32 #define MP2629_ADC_CHAN(_ch, _type) { \ 33 .type = _type, \ 34 .indexed = 1, \ 35 .datasheet_name = #_ch, \ 36 .channel = MP2629_ ## _ch, \ 37 .address = MP2629_REG_ ## _ch, \ 38 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 39 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ 40 } 41 42 struct mp2629_adc { 43 struct regmap *regmap; 44 struct device *dev; 45 }; 46 47 static struct iio_chan_spec mp2629_channels[] = { 48 MP2629_ADC_CHAN(BATT_VOLT, IIO_VOLTAGE), 49 MP2629_ADC_CHAN(SYSTEM_VOLT, IIO_VOLTAGE), 50 MP2629_ADC_CHAN(INPUT_VOLT, IIO_VOLTAGE), 51 MP2629_ADC_CHAN(BATT_CURRENT, IIO_CURRENT), 52 MP2629_ADC_CHAN(INPUT_CURRENT, IIO_CURRENT) 53 }; 54 55 static struct iio_map mp2629_adc_maps[] = { 56 MP2629_MAP(BATT_VOLT, "batt-volt"), 57 MP2629_MAP(SYSTEM_VOLT, "system-volt"), 58 MP2629_MAP(INPUT_VOLT, "input-volt"), 59 MP2629_MAP(BATT_CURRENT, "batt-current"), 60 MP2629_MAP(INPUT_CURRENT, "input-current"), 61 { } 62 }; 63 64 static int mp2629_read_raw(struct iio_dev *indio_dev, 65 struct iio_chan_spec const *chan, 66 int *val, int *val2, long mask) 67 { 68 struct mp2629_adc *info = iio_priv(indio_dev); 69 unsigned int rval; 70 int ret; 71 72 switch (mask) { 73 case IIO_CHAN_INFO_RAW: 74 ret = regmap_read(info->regmap, chan->address, &rval); 75 if (ret) 76 return ret; 77 78 if (chan->channel == MP2629_INPUT_VOLT) 79 rval &= GENMASK(6, 0); 80 *val = rval; 81 return IIO_VAL_INT; 82 83 case IIO_CHAN_INFO_SCALE: 84 switch (chan->channel) { 85 case MP2629_BATT_VOLT: 86 case MP2629_SYSTEM_VOLT: 87 *val = 20; 88 return IIO_VAL_INT; 89 90 case MP2629_INPUT_VOLT: 91 *val = 60; 92 return IIO_VAL_INT; 93 94 case MP2629_BATT_CURRENT: 95 *val = 175; 96 *val2 = 10; 97 return IIO_VAL_FRACTIONAL; 98 99 case MP2629_INPUT_CURRENT: 100 *val = 133; 101 *val2 = 10; 102 return IIO_VAL_FRACTIONAL; 103 104 default: 105 return -EINVAL; 106 } 107 108 default: 109 return -EINVAL; 110 } 111 } 112 113 static const struct iio_info mp2629_adc_info = { 114 .read_raw = &mp2629_read_raw, 115 }; 116 117 static int mp2629_adc_probe(struct platform_device *pdev) 118 { 119 struct device *dev = &pdev->dev; 120 struct mp2629_data *ddata = dev_get_drvdata(dev->parent); 121 struct mp2629_adc *info; 122 struct iio_dev *indio_dev; 123 int ret; 124 125 indio_dev = devm_iio_device_alloc(dev, sizeof(*info)); 126 if (!indio_dev) 127 return -ENOMEM; 128 129 info = iio_priv(indio_dev); 130 info->regmap = ddata->regmap; 131 info->dev = dev; 132 platform_set_drvdata(pdev, indio_dev); 133 134 ret = regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL, 135 MP2629_ADC_START | MP2629_ADC_CONTINUOUS, 136 MP2629_ADC_START | MP2629_ADC_CONTINUOUS); 137 if (ret) { 138 dev_err(dev, "adc enable fail: %d\n", ret); 139 return ret; 140 } 141 142 ret = iio_map_array_register(indio_dev, mp2629_adc_maps); 143 if (ret) { 144 dev_err(dev, "IIO maps register fail: %d\n", ret); 145 goto fail_disable; 146 } 147 148 indio_dev->name = "mp2629-adc"; 149 indio_dev->channels = mp2629_channels; 150 indio_dev->num_channels = ARRAY_SIZE(mp2629_channels); 151 indio_dev->modes = INDIO_DIRECT_MODE; 152 indio_dev->info = &mp2629_adc_info; 153 154 ret = iio_device_register(indio_dev); 155 if (ret) { 156 dev_err(dev, "IIO device register fail: %d\n", ret); 157 goto fail_map_unregister; 158 } 159 160 return 0; 161 162 fail_map_unregister: 163 iio_map_array_unregister(indio_dev); 164 165 fail_disable: 166 regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL, 167 MP2629_ADC_CONTINUOUS, 0); 168 regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL, 169 MP2629_ADC_START, 0); 170 171 return ret; 172 } 173 174 static int mp2629_adc_remove(struct platform_device *pdev) 175 { 176 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 177 struct mp2629_adc *info = iio_priv(indio_dev); 178 179 iio_device_unregister(indio_dev); 180 181 iio_map_array_unregister(indio_dev); 182 183 regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL, 184 MP2629_ADC_CONTINUOUS, 0); 185 regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL, 186 MP2629_ADC_START, 0); 187 188 return 0; 189 } 190 191 static const struct of_device_id mp2629_adc_of_match[] = { 192 { .compatible = "mps,mp2629_adc"}, 193 {} 194 }; 195 MODULE_DEVICE_TABLE(of, mp2629_adc_of_match); 196 197 static struct platform_driver mp2629_adc_driver = { 198 .driver = { 199 .name = "mp2629_adc", 200 .of_match_table = mp2629_adc_of_match, 201 }, 202 .probe = mp2629_adc_probe, 203 .remove = mp2629_adc_remove, 204 }; 205 module_platform_driver(mp2629_adc_driver); 206 207 MODULE_AUTHOR("Saravanan Sekar <sravanhome@gmail.com>"); 208 MODULE_DESCRIPTION("MP2629 ADC driver"); 209 MODULE_LICENSE("GPL"); 210