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1// SPDX-License-Identifier: GPL-2.0+2/*3 * tpl0102.c - Support for Texas Instruments digital potentiometers4 *5 * Copyright (C) 2016, 20186 * Author: Matt Ranostay <matt.ranostay@konsulko.com>7 *8 * TODO: enable/disable hi-z output control9 */10 11#include <linux/module.h>12#include <linux/i2c.h>13#include <linux/regmap.h>14#include <linux/iio/iio.h>15 16struct tpl0102_cfg {17 int wipers;18 int avail[3];19 int kohms;20};21 22enum tpl0102_type {23 CAT5140_503,24 CAT5140_104,25 TPL0102_104,26 TPL0401_103,27};28 29static const struct tpl0102_cfg tpl0102_cfg[] = {30 /* on-semiconductor parts */31 [CAT5140_503] = { .wipers = 1, .avail = { 0, 1, 255 }, .kohms = 50, },32 [CAT5140_104] = { .wipers = 1, .avail = { 0, 1, 255 }, .kohms = 100, },33 /* ti parts */34 [TPL0102_104] = { .wipers = 2, .avail = { 0, 1, 255 }, .kohms = 100 },35 [TPL0401_103] = { .wipers = 1, .avail = { 0, 1, 127 }, .kohms = 10, },36};37 38struct tpl0102_data {39 struct regmap *regmap;40 const struct tpl0102_cfg *cfg;41};42 43static const struct regmap_config tpl0102_regmap_config = {44 .reg_bits = 8,45 .val_bits = 8,46};47 48#define TPL0102_CHANNEL(ch) { \49 .type = IIO_RESISTANCE, \50 .indexed = 1, \51 .output = 1, \52 .channel = (ch), \53 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \54 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \55 .info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW), \56}57 58static const struct iio_chan_spec tpl0102_channels[] = {59 TPL0102_CHANNEL(0),60 TPL0102_CHANNEL(1),61};62 63static int tpl0102_read_raw(struct iio_dev *indio_dev,64 struct iio_chan_spec const *chan,65 int *val, int *val2, long mask)66{67 struct tpl0102_data *data = iio_priv(indio_dev);68 69 switch (mask) {70 case IIO_CHAN_INFO_RAW: {71 int ret = regmap_read(data->regmap, chan->channel, val);72 73 return ret ? ret : IIO_VAL_INT;74 }75 case IIO_CHAN_INFO_SCALE:76 *val = 1000 * data->cfg->kohms;77 *val2 = data->cfg->avail[2] + 1;78 return IIO_VAL_FRACTIONAL;79 }80 81 return -EINVAL;82}83 84static int tpl0102_read_avail(struct iio_dev *indio_dev,85 struct iio_chan_spec const *chan,86 const int **vals, int *type, int *length,87 long mask)88{89 struct tpl0102_data *data = iio_priv(indio_dev);90 91 switch (mask) {92 case IIO_CHAN_INFO_RAW:93 *length = ARRAY_SIZE(data->cfg->avail);94 *vals = data->cfg->avail;95 *type = IIO_VAL_INT;96 return IIO_AVAIL_RANGE;97 }98 99 return -EINVAL;100}101 102static int tpl0102_write_raw(struct iio_dev *indio_dev,103 struct iio_chan_spec const *chan,104 int val, int val2, long mask)105{106 struct tpl0102_data *data = iio_priv(indio_dev);107 108 if (mask != IIO_CHAN_INFO_RAW)109 return -EINVAL;110 111 if (val > data->cfg->avail[2] || val < 0)112 return -EINVAL;113 114 return regmap_write(data->regmap, chan->channel, val);115}116 117static const struct iio_info tpl0102_info = {118 .read_raw = tpl0102_read_raw,119 .read_avail = tpl0102_read_avail,120 .write_raw = tpl0102_write_raw,121};122 123static int tpl0102_probe(struct i2c_client *client)124{125 const struct i2c_device_id *id = i2c_client_get_device_id(client);126 struct device *dev = &client->dev;127 struct tpl0102_data *data;128 struct iio_dev *indio_dev;129 130 indio_dev = devm_iio_device_alloc(dev, sizeof(*data));131 if (!indio_dev)132 return -ENOMEM;133 data = iio_priv(indio_dev);134 i2c_set_clientdata(client, indio_dev);135 136 data->cfg = &tpl0102_cfg[id->driver_data];137 data->regmap = devm_regmap_init_i2c(client, &tpl0102_regmap_config);138 if (IS_ERR(data->regmap)) {139 dev_err(dev, "regmap initialization failed\n");140 return PTR_ERR(data->regmap);141 }142 143 indio_dev->info = &tpl0102_info;144 indio_dev->channels = tpl0102_channels;145 indio_dev->num_channels = data->cfg->wipers;146 indio_dev->name = client->name;147 148 return devm_iio_device_register(dev, indio_dev);149}150 151static const struct i2c_device_id tpl0102_id[] = {152 { "cat5140-503", CAT5140_503 },153 { "cat5140-104", CAT5140_104 },154 { "tpl0102-104", TPL0102_104 },155 { "tpl0401-103", TPL0401_103 },156 {}157};158MODULE_DEVICE_TABLE(i2c, tpl0102_id);159 160static struct i2c_driver tpl0102_driver = {161 .driver = {162 .name = "tpl0102",163 },164 .probe = tpl0102_probe,165 .id_table = tpl0102_id,166};167 168module_i2c_driver(tpl0102_driver);169 170MODULE_AUTHOR("Matt Ranostay <matt.ranostay@konsulko.com>");171MODULE_DESCRIPTION("TPL0102 digital potentiometer");172MODULE_LICENSE("GPL");173