diff options
Diffstat (limited to 'drivers/iio/light/tsl4531.c')
-rw-r--r-- | drivers/iio/light/tsl4531.c | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/drivers/iio/light/tsl4531.c b/drivers/iio/light/tsl4531.c new file mode 100644 index 000000000..06171cb76 --- /dev/null +++ b/drivers/iio/light/tsl4531.c @@ -0,0 +1,260 @@ +/* + * 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, +}; + +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"); |