diff options
Diffstat (limited to 'drivers/iio/temperature/tmp006.c')
| -rw-r--r-- | drivers/iio/temperature/tmp006.c | 293 |
1 files changed, 293 insertions, 0 deletions
diff --git a/drivers/iio/temperature/tmp006.c b/drivers/iio/temperature/tmp006.c new file mode 100644 index 000000000..7a8050996 --- /dev/null +++ b/drivers/iio/temperature/tmp006.c @@ -0,0 +1,293 @@ +/* + * 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 const int tmp006_freqs[5][2] = { {4, 0}, {2, 0}, {1, 0}, + {0, 500000}, {0, 250000} }; + +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; + int cr; + + 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; + case IIO_CHAN_INFO_SAMP_FREQ: + cr = (data->config & TMP006_CONFIG_CR_MASK) + >> TMP006_CONFIG_CR_SHIFT; + *val = tmp006_freqs[cr][0]; + *val2 = tmp006_freqs[cr][1]; + return IIO_VAL_INT_PLUS_MICRO; + default: + break; + } + + return -EINVAL; +} + +static int tmp006_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, + int val2, + long mask) +{ + struct tmp006_data *data = iio_priv(indio_dev); + int i; + + if (mask != IIO_CHAN_INFO_SAMP_FREQ) + return -EINVAL; + + for (i = 0; i < ARRAY_SIZE(tmp006_freqs); i++) + if ((val == tmp006_freqs[i][0]) && + (val2 == tmp006_freqs[i][1])) { + 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); + + } + return -EINVAL; +} + +static IIO_CONST_ATTR(sampling_frequency_available, "4 2 1 0.5 0.25"); + +static struct attribute *tmp006_attributes[] = { + &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), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), + }, + { + .type = IIO_TEMP, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), + } +}; + +static const struct iio_info tmp006_info = { + .read_raw = tmp006_read_raw, + .write_raw = tmp006_write_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) +{ + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); + return tmp006_powerdown(iio_priv(indio_dev)); +} + +static int tmp006_resume(struct device *dev) +{ + struct tmp006_data *data = iio_priv(i2c_get_clientdata( + to_i2c_client(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"); |