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