diff options
Diffstat (limited to 'drivers/iio/adc/ti-adc081c.c')
| -rw-r--r-- | drivers/iio/adc/ti-adc081c.c | 161 | 
1 files changed, 161 insertions, 0 deletions
diff --git a/drivers/iio/adc/ti-adc081c.c b/drivers/iio/adc/ti-adc081c.c new file mode 100644 index 00000000000..f4a46dd8f43 --- /dev/null +++ b/drivers/iio/adc/ti-adc081c.c @@ -0,0 +1,161 @@ +/* + * Copyright (C) 2012 Avionic Design GmbH + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/module.h> + +#include <linux/iio/iio.h> +#include <linux/regulator/consumer.h> + +struct adc081c { +	struct i2c_client *i2c; +	struct regulator *ref; +}; + +#define REG_CONV_RES 0x00 + +static int adc081c_read_raw(struct iio_dev *iio, +			    struct iio_chan_spec const *channel, int *value, +			    int *shift, long mask) +{ +	struct adc081c *adc = iio_priv(iio); +	int err; + +	switch (mask) { +	case IIO_CHAN_INFO_RAW: +		err = i2c_smbus_read_word_swapped(adc->i2c, REG_CONV_RES); +		if (err < 0) +			return err; + +		*value = (err >> 4) & 0xff; +		return IIO_VAL_INT; + +	case IIO_CHAN_INFO_SCALE: +		err = regulator_get_voltage(adc->ref); +		if (err < 0) +			return err; + +		*value = err / 1000; +		*shift = 8; + +		return IIO_VAL_FRACTIONAL_LOG2; + +	default: +		break; +	} + +	return -EINVAL; +} + +static const struct iio_chan_spec adc081c_channel = { +	.type = IIO_VOLTAGE, +	.info_mask = IIO_CHAN_INFO_SCALE_SHARED_BIT | +		     IIO_CHAN_INFO_RAW_SEPARATE_BIT, +}; + +static const struct iio_info adc081c_info = { +	.read_raw = adc081c_read_raw, +	.driver_module = THIS_MODULE, +}; + +static int adc081c_probe(struct i2c_client *client, +			 const struct i2c_device_id *id) +{ +	struct iio_dev *iio; +	struct adc081c *adc; +	int err; + +	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA)) +		return -ENODEV; + +	iio = iio_device_alloc(sizeof(*adc)); +	if (!iio) +		return -ENOMEM; + +	adc = iio_priv(iio); +	adc->i2c = client; + +	adc->ref = regulator_get(&client->dev, "vref"); +	if (IS_ERR(adc->ref)) { +		err = PTR_ERR(adc->ref); +		goto iio_free; +	} + +	err = regulator_enable(adc->ref); +	if (err < 0) +		goto regulator_put; + +	iio->dev.parent = &client->dev; +	iio->name = dev_name(&client->dev); +	iio->modes = INDIO_DIRECT_MODE; +	iio->info = &adc081c_info; + +	iio->channels = &adc081c_channel; +	iio->num_channels = 1; + +	err = iio_device_register(iio); +	if (err < 0) +		goto regulator_disable; + +	i2c_set_clientdata(client, iio); + +	return 0; + +regulator_disable: +	regulator_disable(adc->ref); +regulator_put: +	regulator_put(adc->ref); +iio_free: +	iio_device_free(iio); + +	return err; +} + +static int adc081c_remove(struct i2c_client *client) +{ +	struct iio_dev *iio = i2c_get_clientdata(client); +	struct adc081c *adc = iio_priv(iio); + +	iio_device_unregister(iio); +	regulator_disable(adc->ref); +	regulator_put(adc->ref); +	iio_device_free(iio); + +	return 0; +} + +static const struct i2c_device_id adc081c_id[] = { +	{ "adc081c", 0 }, +	{ } +}; +MODULE_DEVICE_TABLE(i2c, adc081c_id); + +#ifdef CONFIG_OF +static const struct of_device_id adc081c_of_match[] = { +	{ .compatible = "ti,adc081c" }, +	{ } +}; +MODULE_DEVICE_TABLE(of, adc081c_of_match); +#endif + +static struct i2c_driver adc081c_driver = { +	.driver = { +		.name = "adc081c", +		.owner = THIS_MODULE, +		.of_match_table = of_match_ptr(adc081c_of_match), +	}, +	.probe = adc081c_probe, +	.remove = adc081c_remove, +	.id_table = adc081c_id, +}; +module_i2c_driver(adc081c_driver); + +MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>"); +MODULE_DESCRIPTION("Texas Instruments ADC081C021/027 driver"); +MODULE_LICENSE("GPL v2");  |