linux/drivers/iio/light/tsl4531.c

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/*
* tsl4531.c - Support for TAOS TSL4531 ambient light sensor
*
* Copyright 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.
*
* IIO driver for the TSL4531x family
* TSL45311/TSL45313: 7-bit I2C slave address 0x39
* TSL45315/TSL45317: 7-bit I2C slave address 0x29
*
* TODO: single cycle measurement
*/
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#define TSL4531_DRV_NAME "tsl4531"
#define TSL4531_COMMAND BIT(7)
#define TSL4531_CONTROL (TSL4531_COMMAND | 0x00)
#define TSL4531_CONFIG (TSL4531_COMMAND | 0x01)
#define TSL4531_DATA (TSL4531_COMMAND | 0x04)
#define TSL4531_ID (TSL4531_COMMAND | 0x0a)
/* operating modes in control register */
#define TSL4531_MODE_POWERDOWN 0x00
#define TSL4531_MODE_SINGLE_ADC 0x02
#define TSL4531_MODE_NORMAL 0x03
/* integration time control in config register */
#define TSL4531_TCNTRL_400MS 0x00
#define TSL4531_TCNTRL_200MS 0x01
#define TSL4531_TCNTRL_100MS 0x02
/* part number in id register */
#define TSL45311_ID 0x8
#define TSL45313_ID 0x9
#define TSL45315_ID 0xa
#define TSL45317_ID 0xb
#define TSL4531_ID_SHIFT 4
struct tsl4531_data {
struct i2c_client *client;
struct mutex lock;
int int_time;
};
static IIO_CONST_ATTR_INT_TIME_AVAIL("0.1 0.2 0.4");
static struct attribute *tsl4531_attributes[] = {
&iio_const_attr_integration_time_available.dev_attr.attr,
NULL
};
static const struct attribute_group tsl4531_attribute_group = {
.attrs = tsl4531_attributes,
};
static const struct iio_chan_spec tsl4531_channels[] = {
{
.type = IIO_LIGHT,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE) |
BIT(IIO_CHAN_INFO_INT_TIME)
}
};
static int tsl4531_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct tsl4531_data *data = iio_priv(indio_dev);
int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
ret = i2c_smbus_read_word_data(data->client,
TSL4531_DATA);
if (ret < 0)
return ret;
*val = ret;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
/* 0.. 1x, 1 .. 2x, 2 .. 4x */
*val = 1 << data->int_time;
return IIO_VAL_INT;
case IIO_CHAN_INFO_INT_TIME:
if (data->int_time == 0)
*val2 = 400000;
else if (data->int_time == 1)
*val2 = 200000;
else if (data->int_time == 2)
*val2 = 100000;
else
return -EINVAL;
*val = 0;
return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
}
static int tsl4531_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct tsl4531_data *data = iio_priv(indio_dev);
int int_time, ret;
switch (mask) {
case IIO_CHAN_INFO_INT_TIME:
if (val != 0)
return -EINVAL;
if (val2 == 400000)
int_time = 0;
else if (val2 == 200000)
int_time = 1;
else if (val2 == 100000)
int_time = 2;
else
return -EINVAL;
mutex_lock(&data->lock);
ret = i2c_smbus_write_byte_data(data->client,
TSL4531_CONFIG, int_time);
if (ret >= 0)
data->int_time = int_time;
mutex_unlock(&data->lock);
return ret;
default:
return -EINVAL;
}
}
static const struct iio_info tsl4531_info = {
.read_raw = tsl4531_read_raw,
.write_raw = tsl4531_write_raw,
.attrs = &tsl4531_attribute_group,
.driver_module = THIS_MODULE,
};
static int tsl4531_check_id(struct i2c_client *client)
{
int ret = i2c_smbus_read_byte_data(client, TSL4531_ID);
if (ret < 0)
return ret;
switch (ret >> TSL4531_ID_SHIFT) {
case TSL45311_ID:
case TSL45313_ID:
case TSL45315_ID:
case TSL45317_ID:
return 0;
default:
return -ENODEV;
}
}
static int tsl4531_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct tsl4531_data *data;
struct iio_dev *indio_dev;
int ret;
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);
ret = tsl4531_check_id(client);
if (ret) {
dev_err(&client->dev, "no TSL4531 sensor\n");
return ret;
}
ret = i2c_smbus_write_byte_data(data->client, TSL4531_CONTROL,
TSL4531_MODE_NORMAL);
if (ret < 0)
return ret;
ret = i2c_smbus_write_byte_data(data->client, TSL4531_CONFIG,
TSL4531_TCNTRL_400MS);
if (ret < 0)
return ret;
indio_dev->dev.parent = &client->dev;
indio_dev->info = &tsl4531_info;
indio_dev->channels = tsl4531_channels;
indio_dev->num_channels = ARRAY_SIZE(tsl4531_channels);
indio_dev->name = TSL4531_DRV_NAME;
indio_dev->modes = INDIO_DIRECT_MODE;
return iio_device_register(indio_dev);
}
static int tsl4531_powerdown(struct i2c_client *client)
{
return i2c_smbus_write_byte_data(client, TSL4531_CONTROL,
TSL4531_MODE_POWERDOWN);
}
static int tsl4531_remove(struct i2c_client *client)
{
iio_device_unregister(i2c_get_clientdata(client));
tsl4531_powerdown(client);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int tsl4531_suspend(struct device *dev)
{
return tsl4531_powerdown(to_i2c_client(dev));
}
static int tsl4531_resume(struct device *dev)
{
return i2c_smbus_write_byte_data(to_i2c_client(dev), TSL4531_CONTROL,
TSL4531_MODE_NORMAL);
}
static SIMPLE_DEV_PM_OPS(tsl4531_pm_ops, tsl4531_suspend, tsl4531_resume);
#define TSL4531_PM_OPS (&tsl4531_pm_ops)
#else
#define TSL4531_PM_OPS NULL
#endif
static const struct i2c_device_id tsl4531_id[] = {
{ "tsl4531", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, tsl4531_id);
static struct i2c_driver tsl4531_driver = {
.driver = {
.name = TSL4531_DRV_NAME,
.pm = TSL4531_PM_OPS,
},
.probe = tsl4531_probe,
.remove = tsl4531_remove,
.id_table = tsl4531_id,
};
module_i2c_driver(tsl4531_driver);
MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
MODULE_DESCRIPTION("TAOS TSL4531 ambient light sensors driver");
MODULE_LICENSE("GPL");