forked from luck/tmp_suning_uos_patched
iio: adc: Add Texas Instruments ADC081C021/027 support
Add support for reading conversion results from the ADC and provide them through a single IIO channel. A proper scaling factor is also exported based on the reference voltage provided by a regulator. Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de> Reviewed-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This commit is contained in:
parent
fd1a8b9128
commit
bc0a409c5f
@ -115,4 +115,14 @@ config MAX1363
|
||||
max11646, max11647) Provides direct access via sysfs and buffered
|
||||
data via the iio dev interface.
|
||||
|
||||
config TI_ADC081C
|
||||
tristate "Texas Instruments ADC081C021/027"
|
||||
depends on I2C
|
||||
help
|
||||
If you say yes here you get support for Texas Instruments ADC081C021
|
||||
and ADC081C027 ADC chips.
|
||||
|
||||
This driver can also be built as a module. If so, the module will be
|
||||
called ti-adc081c.
|
||||
|
||||
endmenu
|
||||
|
@ -12,3 +12,5 @@ obj-$(CONFIG_AD7887) += ad7887.o
|
||||
obj-$(CONFIG_AT91_ADC) += at91_adc.o
|
||||
obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o
|
||||
obj-$(CONFIG_MAX1363) += max1363.o
|
||||
obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
|
||||
|
||||
|
161
drivers/iio/adc/ti-adc081c.c
Normal file
161
drivers/iio/adc/ti-adc081c.c
Normal file
@ -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");
|
Loading…
Reference in New Issue
Block a user