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 static int mp2629_read_raw(struct iio_dev *indio_dev, 64 struct iio_chan_spec const *chan, 65 int *val, int *val2, long mask) 66 { 67 struct mp2629_adc *info = iio_priv(indio_dev); 68 unsigned int rval; 69 int ret; 70 71 switch (mask) { 72 case IIO_CHAN_INFO_RAW: 73 ret = regmap_read(info->regmap, chan->address, &rval); 74 if (ret) 75 return ret; 76 77 if (chan->address == MP2629_INPUT_VOLT) 78 rval &= GENMASK(6, 0); 79 *val = rval; 80 return IIO_VAL_INT; 81 82 case IIO_CHAN_INFO_SCALE: 83 switch (chan->channel) { 84 case MP2629_BATT_VOLT: 85 case MP2629_SYSTEM_VOLT: 86 *val = 20; 87 return IIO_VAL_INT; 88 89 case MP2629_INPUT_VOLT: 90 *val = 60; 91 return IIO_VAL_INT; 92 93 case MP2629_BATT_CURRENT: 94 *val = 175; 95 *val2 = 10; 96 return IIO_VAL_FRACTIONAL; 97 98 case MP2629_INPUT_CURRENT: 99 *val = 133; 100 *val2 = 10; 101 return IIO_VAL_FRACTIONAL; 102 103 default: 104 return -EINVAL; 105 } 106 107 default: 108 return -EINVAL; 109 } 110 } 111 112 static const struct iio_info mp2629_adc_info = { 113 .read_raw = &mp2629_read_raw, 114 }; 115 116 static int mp2629_adc_probe(struct platform_device *pdev) 117 { 118 struct device *dev = &pdev->dev; 119 struct mp2629_data *ddata = dev_get_drvdata(dev->parent); 120 struct mp2629_adc *info; 121 struct iio_dev *indio_dev; 122 int ret; 123 124 indio_dev = devm_iio_device_alloc(dev, sizeof(*info)); 125 if (!indio_dev) 126 return -ENOMEM; 127 128 info = iio_priv(indio_dev); 129 info->regmap = ddata->regmap; 130 info->dev = dev; 131 platform_set_drvdata(pdev, indio_dev); 132 133 ret = regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL, 134 MP2629_ADC_START | MP2629_ADC_CONTINUOUS, 135 MP2629_ADC_START | MP2629_ADC_CONTINUOUS); 136 if (ret) { 137 dev_err(dev, "adc enable fail: %d\n", ret); 138 return ret; 139 } 140 141 ret = iio_map_array_register(indio_dev, mp2629_adc_maps); 142 if (ret) { 143 dev_err(dev, "IIO maps register fail: %d\n", ret); 144 goto fail_disable; 145 } 146 147 indio_dev->name = "mp2629-adc"; 148 indio_dev->channels = mp2629_channels; 149 indio_dev->num_channels = ARRAY_SIZE(mp2629_channels); 150 indio_dev->modes = INDIO_DIRECT_MODE; 151 indio_dev->info = &mp2629_adc_info; 152 153 ret = iio_device_register(indio_dev); 154 if (ret) { 155 dev_err(dev, "IIO device register fail: %d\n", ret); 156 goto fail_map_unregister; 157 } 158 159 return 0; 160 161 fail_map_unregister: 162 iio_map_array_unregister(indio_dev); 163 164 fail_disable: 165 regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL, 166 MP2629_ADC_CONTINUOUS, 0); 167 regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL, 168 MP2629_ADC_START, 0); 169 170 return ret; 171 } 172 173 static int mp2629_adc_remove(struct platform_device *pdev) 174 { 175 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 176 struct mp2629_adc *info = iio_priv(indio_dev); 177 178 iio_device_unregister(indio_dev); 179 180 iio_map_array_unregister(indio_dev); 181 182 regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL, 183 MP2629_ADC_CONTINUOUS, 0); 184 regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL, 185 MP2629_ADC_START, 0); 186 187 return 0; 188 } 189 190 static const struct of_device_id mp2629_adc_of_match[] = { 191 { .compatible = "mps,mp2629_adc"}, 192 {} 193 }; 194 MODULE_DEVICE_TABLE(of, mp2629_adc_of_match); 195 196 static struct platform_driver mp2629_adc_driver = { 197 .driver = { 198 .name = "mp2629_adc", 199 .of_match_table = mp2629_adc_of_match, 200 }, 201 .probe = mp2629_adc_probe, 202 .remove = mp2629_adc_remove, 203 }; 204 module_platform_driver(mp2629_adc_driver); 205 206 MODULE_AUTHOR("Saravanan Sekar <sravanhome@gmail.com>"); 207 MODULE_DESCRIPTION("MP2629 ADC driver"); 208 MODULE_LICENSE("GPL"); 209