/*
* tmp006.c - Support for TI TMP006 IR thermopile sensor
*
* Copyright (c) 2013 Peter Meerwald <pmeerw@pmeerw.net>
*
* This file is subject to the terms and conditions of version 2 of
* the GNU General Public License. See the file COPYING in the main
* directory of this archive for more details.
*
* Driver for the Texas Instruments I2C 16-bit IR thermopile sensor
*
* (7-bit I2C slave address 0x40, changeable via ADR pins)
*
* TODO: data ready irq
*/
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/pm.h>
#include <linux/bitops.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#define TMP006_VOBJECT 0x00
#define TMP006_TAMBIENT 0x01
#define TMP006_CONFIG 0x02
#define TMP006_MANUFACTURER_ID 0xfe
#define TMP006_DEVICE_ID 0xff
#define TMP006_TAMBIENT_SHIFT 2
#define TMP006_CONFIG_RESET BIT(15)
#define TMP006_CONFIG_DRDY_EN BIT(8)
#define TMP006_CONFIG_DRDY BIT(7)
#define TMP006_CONFIG_MOD_MASK 0x7000
#define TMP006_CONFIG_CR_MASK 0x0e00
#define TMP006_CONFIG_CR_SHIFT 9
#define MANUFACTURER_MAGIC 0x5449
#define DEVICE_MAGIC 0x0067
struct tmp006_data {
struct i2c_client *client;
u16 config;
};
static int tmp006_read_measurement(struct tmp006_data *data, u8 reg)
{
s32 ret;
int tries = 50;
while (tries-- > 0) {
ret = i2c_smbus_read_word_swapped(data->client,
TMP006_CONFIG);
if (ret < 0)
return ret;
if (ret & TMP006_CONFIG_DRDY)
break;
msleep(100);
}
if (tries < 0)
return -EIO;
return i2c_smbus_read_word_swapped(data->client, reg);
}
static int tmp006_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *channel, int *val,
int *val2, long mask)
{
struct tmp006_data *data = iio_priv(indio_dev);
s32 ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
if (channel->type == IIO_VOLTAGE) {
/* LSB is 156.25 nV */
ret = tmp006_read_measurement(data, TMP006_VOBJECT);
if (ret < 0)
return ret;
*val = sign_extend32(ret, 15);
} else if (channel->type == IIO_TEMP) {
/* LSB is 0.03125 degrees Celsius */
ret = tmp006_read_measurement(data, TMP006_TAMBIENT);
if (ret < 0)
return ret;
*val = sign_extend32(ret, 15) >> TMP006_TAMBIENT_SHIFT;
} else {
break;
}
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
if (channel->type == IIO_VOLTAGE) {
*val = 0;
*val2 = 156250;
} else if (channel->type == IIO_TEMP) {
*val = 31;
*val2 = 250000;
} else {
break;
}
return IIO_VAL_INT_PLUS_MICRO;
default:
break;
}
return -EINVAL;
}
static const char * const tmp006_freqs[] = { "4", "2", "1", "0.5", "0.25" };
static ssize_t tmp006_show_freq(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct tmp006_data *data = iio_priv(dev_to_iio_dev(dev));
int cr = (data->config & TMP006_CONFIG_CR_MASK)
>> TMP006_CONFIG_CR_SHIFT;
return sprintf(buf, "%s\n", tmp006_freqs[cr]);
}
static ssize_t tmp006_store_freq(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct tmp006_data *data = iio_priv(indio_dev);
int i;
bool found = false;
for (i = 0; i < ARRAY_SIZE(tmp006_freqs); i++)
if (sysfs_streq(buf, tmp006_freqs[i])) {
found = true;
break;
}
if (!found)
return -EINVAL;
data->config &= ~TMP006_CONFIG_CR_MASK;
data->config |= i << TMP006_CONFIG_CR_SHIFT;
return i2c_smbus_write_word_swapped(data->client, TMP006_CONFIG,
data->config);
}
static IIO_DEV_ATTR_SAMP_FREQ(S_IRUGO | S_IWUSR,
tmp006_show_freq, tmp006_store_freq);
static IIO_CONST_ATTR(sampling_frequency_available, "4 2 1 0.5 0.25");
static struct attribute *tmp006_attributes[] = {
&iio_dev_attr_sampling_frequency.dev_attr.attr,
&iio_const_attr_sampling_frequency_available.dev_attr.attr,
NULL
};
static const struct attribute_group tmp006_attribute_group = {
.attrs = tmp006_attributes,
};
static const struct iio_chan_spec tmp006_channels[] = {
{
.type = IIO_VOLTAGE,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
},
{
.type = IIO_TEMP,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
}
};
static const struct iio_info tmp006_info = {
.read_raw = tmp006_read_raw,
.attrs = &tmp006_attribute_group,
.driver_module = THIS_MODULE,
};
static bool tmp006_check_identification(struct i2c_client *client)
{
int mid, did;
mid = i2c_smbus_read_word_swapped(client, TMP006_MANUFACTURER_ID);
if (mid < 0)
return false;
did = i2c_smbus_read_word_swapped(client, TMP006_DEVICE_ID);
if (did < 0)
return false;
return mid == MANUFACTURER_MAGIC && did == DEVICE_MAGIC;
}
static int tmp006_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct iio_dev *indio_dev;
struct tmp006_data *data;
int ret;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
return -ENODEV;
if (!tmp006_check_identification(client)) {
dev_err(&client->dev, "no TMP006 sensor\n");
return -ENODEV;
}
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;
indio_dev->dev.parent = &client->dev;
indio_dev->name = dev_name(&client->dev);
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->info = &tmp006_info;
indio_dev->channels = tmp006_channels;
indio_dev->num_channels = ARRAY_SIZE(tmp006_channels);
ret = i2c_smbus_read_word_swapped(data->client, TMP006_CONFIG);
if (ret < 0)
return ret;
data->config = ret;
return iio_device_register(indio_dev);
}
static int tmp006_powerdown(struct tmp006_data *data)
{
return i2c_smbus_write_word_swapped(data->client, TMP006_CONFIG,
data->config & ~TMP006_CONFIG_MOD_MASK);
}
static int tmp006_remove(struct i2c_client *client)
{
struct iio_dev *indio_dev = i2c_get_clientdata(client);
iio_device_unregister(indio_dev);
tmp006_powerdown(iio_priv(indio_dev));
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int tmp006_suspend(struct device *dev)
{
return tmp006_powerdown(iio_priv(dev_to_iio_dev(dev)));
}
static int tmp006_resume(struct device *dev)
{
struct tmp006_data *data = iio_priv(dev_to_iio_dev(dev));
return i2c_smbus_write_word_swapped(data->client, TMP006_CONFIG,
data->config | TMP006_CONFIG_MOD_MASK);
}
#endif
static SIMPLE_DEV_PM_OPS(tmp006_pm_ops, tmp006_suspend, tmp006_resume);
static const struct i2c_device_id tmp006_id[] = {
{ "tmp006", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, tmp006_id);
static struct i2c_driver tmp006_driver = {
.driver = {
.name = "tmp006",
.pm = &tmp006_pm_ops,
.owner = THIS_MODULE,
},
.probe = tmp006_probe,
.remove = tmp006_remove,
.id_table = tmp006_id,
};
module_i2c_driver(tmp006_driver);
MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
MODULE_DESCRIPTION("TI TMP006 IR thermopile sensor driver");
MODULE_LICENSE("GPL");
