| /* |
| * t5403.c - Support for EPCOS T5403 pressure/temperature sensor |
| * |
| * Copyright (c) 2014 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. |
| * |
| * (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, |
| .driver_module = THIS_MODULE, |
| }; |
| |
| 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->dev.parent = &client->dev; |
| 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"); |