271 lines
6.2 KiB
C
271 lines
6.2 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* t5403.c - Support for EPCOS T5403 pressure/temperature sensor
|
|
*
|
|
* Copyright (c) 2014 Peter Meerwald <pmeerw@pmeerw.net>
|
|
*
|
|
* (7-bit I2C slave address 0x77)
|
|
*
|
|
* TODO: end-of-conversion irq
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/iio/iio.h>
|
|
#include <linux/iio/sysfs.h>
|
|
#include <linux/delay.h>
|
|
|
|
#define T5403_DATA 0xf5 /* data, LSB first, 16 bit */
|
|
#define T5403_CALIB_DATA 0x8e /* 10 calibration coeff., LSB first, 16 bit */
|
|
#define T5403_SLAVE_ADDR 0x88 /* I2C slave address, 0x77 */
|
|
#define T5403_COMMAND 0xf1
|
|
|
|
/* command bits */
|
|
#define T5403_MODE_SHIFT 3 /* conversion time: 2, 8, 16, 66 ms */
|
|
#define T5403_PT BIT(1) /* 0 .. pressure, 1 .. temperature measurement */
|
|
#define T5403_SCO BIT(0) /* start conversion */
|
|
|
|
#define T5403_MODE_LOW 0
|
|
#define T5403_MODE_STANDARD 1
|
|
#define T5403_MODE_HIGH 2
|
|
#define T5403_MODE_ULTRA_HIGH 3
|
|
|
|
#define T5403_I2C_MASK (~BIT(7))
|
|
#define T5403_I2C_ADDR 0x77
|
|
|
|
static const int t5403_pressure_conv_ms[] = {2, 8, 16, 66};
|
|
|
|
struct t5403_data {
|
|
struct i2c_client *client;
|
|
struct mutex lock;
|
|
int mode;
|
|
__le16 c[10];
|
|
};
|
|
|
|
#define T5403_C_U16(i) le16_to_cpu(data->c[(i) - 1])
|
|
#define T5403_C(i) sign_extend32(T5403_C_U16(i), 15)
|
|
|
|
static int t5403_read(struct t5403_data *data, bool pressure)
|
|
{
|
|
int wait_time = 3; /* wakeup time in ms */
|
|
|
|
int ret = i2c_smbus_write_byte_data(data->client, T5403_COMMAND,
|
|
(pressure ? (data->mode << T5403_MODE_SHIFT) : T5403_PT) |
|
|
T5403_SCO);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
wait_time += pressure ? t5403_pressure_conv_ms[data->mode] : 2;
|
|
|
|
msleep(wait_time);
|
|
|
|
return i2c_smbus_read_word_data(data->client, T5403_DATA);
|
|
}
|
|
|
|
static int t5403_comp_pressure(struct t5403_data *data, int *val, int *val2)
|
|
{
|
|
int ret;
|
|
s16 t_r;
|
|
u16 p_r;
|
|
s32 S, O, X;
|
|
|
|
mutex_lock(&data->lock);
|
|
|
|
ret = t5403_read(data, false);
|
|
if (ret < 0)
|
|
goto done;
|
|
t_r = ret;
|
|
|
|
ret = t5403_read(data, true);
|
|
if (ret < 0)
|
|
goto done;
|
|
p_r = ret;
|
|
|
|
/* see EPCOS application note */
|
|
S = T5403_C_U16(3) + (s32) T5403_C_U16(4) * t_r / 0x20000 +
|
|
T5403_C(5) * t_r / 0x8000 * t_r / 0x80000 +
|
|
T5403_C(9) * t_r / 0x8000 * t_r / 0x8000 * t_r / 0x10000;
|
|
|
|
O = T5403_C(6) * 0x4000 + T5403_C(7) * t_r / 8 +
|
|
T5403_C(8) * t_r / 0x8000 * t_r / 16 +
|
|
T5403_C(9) * t_r / 0x8000 * t_r / 0x10000 * t_r;
|
|
|
|
X = (S * p_r + O) / 0x4000;
|
|
|
|
X += ((X - 75000) * (X - 75000) / 0x10000 - 9537) *
|
|
T5403_C(10) / 0x10000;
|
|
|
|
*val = X / 1000;
|
|
*val2 = (X % 1000) * 1000;
|
|
|
|
done:
|
|
mutex_unlock(&data->lock);
|
|
return ret;
|
|
}
|
|
|
|
static int t5403_comp_temp(struct t5403_data *data, int *val)
|
|
{
|
|
int ret;
|
|
s16 t_r;
|
|
|
|
mutex_lock(&data->lock);
|
|
ret = t5403_read(data, false);
|
|
if (ret < 0)
|
|
goto done;
|
|
t_r = ret;
|
|
|
|
/* see EPCOS application note */
|
|
*val = ((s32) T5403_C_U16(1) * t_r / 0x100 +
|
|
(s32) T5403_C_U16(2) * 0x40) * 1000 / 0x10000;
|
|
|
|
done:
|
|
mutex_unlock(&data->lock);
|
|
return ret;
|
|
}
|
|
|
|
static int t5403_read_raw(struct iio_dev *indio_dev,
|
|
struct iio_chan_spec const *chan,
|
|
int *val, int *val2, long mask)
|
|
{
|
|
struct t5403_data *data = iio_priv(indio_dev);
|
|
int ret;
|
|
|
|
switch (mask) {
|
|
case IIO_CHAN_INFO_PROCESSED:
|
|
switch (chan->type) {
|
|
case IIO_PRESSURE:
|
|
ret = t5403_comp_pressure(data, val, val2);
|
|
if (ret < 0)
|
|
return ret;
|
|
return IIO_VAL_INT_PLUS_MICRO;
|
|
case IIO_TEMP:
|
|
ret = t5403_comp_temp(data, val);
|
|
if (ret < 0)
|
|
return ret;
|
|
return IIO_VAL_INT;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
case IIO_CHAN_INFO_INT_TIME:
|
|
*val = 0;
|
|
*val2 = t5403_pressure_conv_ms[data->mode] * 1000;
|
|
return IIO_VAL_INT_PLUS_MICRO;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
static int t5403_write_raw(struct iio_dev *indio_dev,
|
|
struct iio_chan_spec const *chan,
|
|
int val, int val2, long mask)
|
|
{
|
|
struct t5403_data *data = iio_priv(indio_dev);
|
|
int i;
|
|
|
|
switch (mask) {
|
|
case IIO_CHAN_INFO_INT_TIME:
|
|
if (val != 0)
|
|
return -EINVAL;
|
|
for (i = 0; i < ARRAY_SIZE(t5403_pressure_conv_ms); i++)
|
|
if (val2 == t5403_pressure_conv_ms[i] * 1000) {
|
|
mutex_lock(&data->lock);
|
|
data->mode = i;
|
|
mutex_unlock(&data->lock);
|
|
return 0;
|
|
}
|
|
return -EINVAL;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
static const struct iio_chan_spec t5403_channels[] = {
|
|
{
|
|
.type = IIO_PRESSURE,
|
|
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
|
|
BIT(IIO_CHAN_INFO_INT_TIME),
|
|
},
|
|
{
|
|
.type = IIO_TEMP,
|
|
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
|
|
},
|
|
};
|
|
|
|
static IIO_CONST_ATTR_INT_TIME_AVAIL("0.002 0.008 0.016 0.066");
|
|
|
|
static struct attribute *t5403_attributes[] = {
|
|
&iio_const_attr_integration_time_available.dev_attr.attr,
|
|
NULL
|
|
};
|
|
|
|
static const struct attribute_group t5403_attribute_group = {
|
|
.attrs = t5403_attributes,
|
|
};
|
|
|
|
static const struct iio_info t5403_info = {
|
|
.read_raw = &t5403_read_raw,
|
|
.write_raw = &t5403_write_raw,
|
|
.attrs = &t5403_attribute_group,
|
|
};
|
|
|
|
static int t5403_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
struct t5403_data *data;
|
|
struct iio_dev *indio_dev;
|
|
int ret;
|
|
|
|
if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA |
|
|
I2C_FUNC_SMBUS_I2C_BLOCK))
|
|
return -EOPNOTSUPP;
|
|
|
|
ret = i2c_smbus_read_byte_data(client, T5403_SLAVE_ADDR);
|
|
if (ret < 0)
|
|
return ret;
|
|
if ((ret & T5403_I2C_MASK) != T5403_I2C_ADDR)
|
|
return -ENODEV;
|
|
|
|
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
|
|
if (!indio_dev)
|
|
return -ENOMEM;
|
|
|
|
data = iio_priv(indio_dev);
|
|
data->client = client;
|
|
mutex_init(&data->lock);
|
|
|
|
i2c_set_clientdata(client, indio_dev);
|
|
indio_dev->info = &t5403_info;
|
|
indio_dev->name = id->name;
|
|
indio_dev->modes = INDIO_DIRECT_MODE;
|
|
indio_dev->channels = t5403_channels;
|
|
indio_dev->num_channels = ARRAY_SIZE(t5403_channels);
|
|
|
|
data->mode = T5403_MODE_STANDARD;
|
|
|
|
ret = i2c_smbus_read_i2c_block_data(data->client, T5403_CALIB_DATA,
|
|
sizeof(data->c), (u8 *) data->c);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
return devm_iio_device_register(&client->dev, indio_dev);
|
|
}
|
|
|
|
static const struct i2c_device_id t5403_id[] = {
|
|
{ "t5403", 0 },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, t5403_id);
|
|
|
|
static struct i2c_driver t5403_driver = {
|
|
.driver = {
|
|
.name = "t5403",
|
|
},
|
|
.probe = t5403_probe,
|
|
.id_table = t5403_id,
|
|
};
|
|
module_i2c_driver(t5403_driver);
|
|
|
|
MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
|
|
MODULE_DESCRIPTION("EPCOS T5403 pressure/temperature sensor driver");
|
|
MODULE_LICENSE("GPL");
|