Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 | /*
* tpl0102.c - Support for Texas Instruments digital potentiometers
*
* Copyright (C) 2016 Matt Ranostay <mranostay@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* TODO: enable/disable hi-z output control
*/
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/regmap.h>
#include <linux/iio/iio.h>
struct tpl0102_cfg {
int wipers;
int max_pos;
int kohms;
};
enum tpl0102_type {
CAT5140_503,
CAT5140_104,
TPL0102_104,
TPL0401_103,
};
static const struct tpl0102_cfg tpl0102_cfg[] = {
/* on-semiconductor parts */
[CAT5140_503] = { .wipers = 1, .max_pos = 256, .kohms = 50, },
[CAT5140_104] = { .wipers = 1, .max_pos = 256, .kohms = 100, },
/* ti parts */
[TPL0102_104] = { .wipers = 2, .max_pos = 256, .kohms = 100 },
[TPL0401_103] = { .wipers = 1, .max_pos = 128, .kohms = 10, },
};
struct tpl0102_data {
struct regmap *regmap;
unsigned long devid;
};
static const struct regmap_config tpl0102_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
};
#define TPL0102_CHANNEL(ch) { \
.type = IIO_RESISTANCE, \
.indexed = 1, \
.output = 1, \
.channel = (ch), \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
}
static const struct iio_chan_spec tpl0102_channels[] = {
TPL0102_CHANNEL(0),
TPL0102_CHANNEL(1),
};
static int tpl0102_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct tpl0102_data *data = iio_priv(indio_dev);
switch (mask) {
case IIO_CHAN_INFO_RAW: {
int ret = regmap_read(data->regmap, chan->channel, val);
return ret ? ret : IIO_VAL_INT;
}
case IIO_CHAN_INFO_SCALE:
*val = 1000 * tpl0102_cfg[data->devid].kohms;
*val2 = tpl0102_cfg[data->devid].max_pos;
return IIO_VAL_FRACTIONAL;
}
return -EINVAL;
}
static int tpl0102_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct tpl0102_data *data = iio_priv(indio_dev);
if (mask != IIO_CHAN_INFO_RAW)
return -EINVAL;
if (val >= tpl0102_cfg[data->devid].max_pos || val < 0)
return -EINVAL;
return regmap_write(data->regmap, chan->channel, val);
}
static const struct iio_info tpl0102_info = {
.read_raw = tpl0102_read_raw,
.write_raw = tpl0102_write_raw,
.driver_module = THIS_MODULE,
};
static int tpl0102_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct device *dev = &client->dev;
struct tpl0102_data *data;
struct iio_dev *indio_dev;
indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
data = iio_priv(indio_dev);
i2c_set_clientdata(client, indio_dev);
data->devid = id->driver_data;
data->regmap = devm_regmap_init_i2c(client, &tpl0102_regmap_config);
if (IS_ERR(data->regmap)) {
dev_err(dev, "regmap initialization failed\n");
return PTR_ERR(data->regmap);
}
indio_dev->dev.parent = dev;
indio_dev->info = &tpl0102_info;
indio_dev->channels = tpl0102_channels;
indio_dev->num_channels = tpl0102_cfg[data->devid].wipers;
indio_dev->name = client->name;
return devm_iio_device_register(dev, indio_dev);
}
static const struct i2c_device_id tpl0102_id[] = {
{ "cat5140-503", CAT5140_503 },
{ "cat5140-104", CAT5140_104 },
{ "tpl0102-104", TPL0102_104 },
{ "tpl0401-103", TPL0401_103 },
{}
};
MODULE_DEVICE_TABLE(i2c, tpl0102_id);
static struct i2c_driver tpl0102_driver = {
.driver = {
.name = "tpl0102",
},
.probe = tpl0102_probe,
.id_table = tpl0102_id,
};
module_i2c_driver(tpl0102_driver);
MODULE_AUTHOR("Matt Ranostay <mranostay@gmail.com>");
MODULE_DESCRIPTION("TPL0102 digital potentiometer");
MODULE_LICENSE("GPL");
|