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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 | // SPDX-License-Identifier: GPL-2.0-only
/*
* si7005.c - Support for Silabs Si7005 humidity and temperature sensor
*
* Copyright (c) 2014 Peter Meerwald <pmeerw@pmeerw.net>
*
* (7-bit I2C slave address 0x40)
*
* TODO: heater, fast mode, processed mode (temp. / linearity compensation)
*/
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/pm.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#define SI7005_STATUS 0x00
#define SI7005_DATA 0x01 /* 16-bit, MSB */
#define SI7005_CONFIG 0x03
#define SI7005_ID 0x11
#define SI7005_STATUS_NRDY BIT(0)
#define SI7005_CONFIG_TEMP BIT(4)
#define SI7005_CONFIG_START BIT(0)
#define SI7005_ID_7005 0x50
#define SI7005_ID_7015 0xf0
struct si7005_data {
struct i2c_client *client;
struct mutex lock;
u8 config;
};
static int si7005_read_measurement(struct si7005_data *data, bool temp)
{
int tries = 50;
int ret;
mutex_lock(&data->lock);
ret = i2c_smbus_write_byte_data(data->client, SI7005_CONFIG,
data->config | SI7005_CONFIG_START |
(temp ? SI7005_CONFIG_TEMP : 0));
if (ret < 0)
goto done;
while (tries-- > 0) {
msleep(20);
ret = i2c_smbus_read_byte_data(data->client, SI7005_STATUS);
if (ret < 0)
goto done;
if (!(ret & SI7005_STATUS_NRDY))
break;
}
if (tries < 0) {
ret = -EIO;
goto done;
}
ret = i2c_smbus_read_word_swapped(data->client, SI7005_DATA);
done:
mutex_unlock(&data->lock);
return ret;
}
static int si7005_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int *val,
int *val2, long mask)
{
struct si7005_data *data = iio_priv(indio_dev);
int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
ret = si7005_read_measurement(data, chan->type == IIO_TEMP);
if (ret < 0)
return ret;
*val = ret;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
if (chan->type == IIO_TEMP) {
*val = 7;
*val2 = 812500;
} else {
*val = 3;
*val2 = 906250;
}
return IIO_VAL_INT_PLUS_MICRO;
case IIO_CHAN_INFO_OFFSET:
if (chan->type == IIO_TEMP)
*val = -50 * 32 * 4;
else
*val = -24 * 16 * 16;
return IIO_VAL_INT;
default:
break;
}
return -EINVAL;
}
static const struct iio_chan_spec si7005_channels[] = {
{
.type = IIO_HUMIDITYRELATIVE,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_OFFSET),
},
{
.type = IIO_TEMP,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_OFFSET),
}
};
static const struct iio_info si7005_info = {
.read_raw = si7005_read_raw,
};
static int si7005_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct iio_dev *indio_dev;
struct si7005_data *data;
int ret;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
return -EOPNOTSUPP;
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
data = iio_priv(indio_dev);
i2c_set_clientdata(client, indio_dev);
data->client = client;
mutex_init(&data->lock);
indio_dev->dev.parent = &client->dev;
indio_dev->name = dev_name(&client->dev);
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->info = &si7005_info;
indio_dev->channels = si7005_channels;
indio_dev->num_channels = ARRAY_SIZE(si7005_channels);
ret = i2c_smbus_read_byte_data(client, SI7005_ID);
if (ret < 0)
return ret;
if (ret != SI7005_ID_7005 && ret != SI7005_ID_7015)
return -ENODEV;
ret = i2c_smbus_read_byte_data(client, SI7005_CONFIG);
if (ret < 0)
return ret;
data->config = ret;
return devm_iio_device_register(&client->dev, indio_dev);
}
static const struct i2c_device_id si7005_id[] = {
{ "si7005", 0 },
{ "th02", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, si7005_id);
static struct i2c_driver si7005_driver = {
.driver = {
.name = "si7005",
},
.probe = si7005_probe,
.id_table = si7005_id,
};
module_i2c_driver(si7005_driver);
MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
MODULE_DESCRIPTION("Silabs Si7005 humidity and temperature sensor driver");
MODULE_LICENSE("GPL");
|