135 lines
3.0 KiB
C
135 lines
3.0 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* AD7314 digital temperature sensor driver for AD7314, ADT7301 and ADT7302
|
|
*
|
|
* Copyright 2010 Analog Devices Inc.
|
|
*
|
|
* Conversion to hwmon from IIO done by Jonathan Cameron <jic23@cam.ac.uk>
|
|
*/
|
|
#include <linux/device.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/sysfs.h>
|
|
#include <linux/spi/spi.h>
|
|
#include <linux/module.h>
|
|
#include <linux/err.h>
|
|
#include <linux/hwmon.h>
|
|
#include <linux/hwmon-sysfs.h>
|
|
#include <linux/bitops.h>
|
|
|
|
/*
|
|
* AD7314 temperature masks
|
|
*/
|
|
#define AD7314_TEMP_MASK 0x7FE0
|
|
#define AD7314_TEMP_SHIFT 5
|
|
|
|
/*
|
|
* ADT7301 and ADT7302 temperature masks
|
|
*/
|
|
#define ADT7301_TEMP_MASK 0x3FFF
|
|
|
|
enum ad7314_variant {
|
|
adt7301,
|
|
adt7302,
|
|
ad7314,
|
|
};
|
|
|
|
struct ad7314_data {
|
|
struct spi_device *spi_dev;
|
|
u16 rx ____cacheline_aligned;
|
|
};
|
|
|
|
static int ad7314_spi_read(struct ad7314_data *chip)
|
|
{
|
|
int ret;
|
|
|
|
ret = spi_read(chip->spi_dev, (u8 *)&chip->rx, sizeof(chip->rx));
|
|
if (ret < 0) {
|
|
dev_err(&chip->spi_dev->dev, "SPI read error\n");
|
|
return ret;
|
|
}
|
|
|
|
return be16_to_cpu(chip->rx);
|
|
}
|
|
|
|
static ssize_t ad7314_temperature_show(struct device *dev,
|
|
struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
struct ad7314_data *chip = dev_get_drvdata(dev);
|
|
s16 data;
|
|
int ret;
|
|
|
|
ret = ad7314_spi_read(chip);
|
|
if (ret < 0)
|
|
return ret;
|
|
switch (spi_get_device_id(chip->spi_dev)->driver_data) {
|
|
case ad7314:
|
|
data = (ret & AD7314_TEMP_MASK) >> AD7314_TEMP_SHIFT;
|
|
data = sign_extend32(data, 9);
|
|
|
|
return sprintf(buf, "%d\n", 250 * data);
|
|
case adt7301:
|
|
case adt7302:
|
|
/*
|
|
* Documented as a 13 bit twos complement register
|
|
* with a sign bit - which is a 14 bit 2's complement
|
|
* register. 1lsb - 31.25 milli degrees centigrade
|
|
*/
|
|
data = ret & ADT7301_TEMP_MASK;
|
|
data = sign_extend32(data, 13);
|
|
|
|
return sprintf(buf, "%d\n",
|
|
DIV_ROUND_CLOSEST(data * 3125, 100));
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
static SENSOR_DEVICE_ATTR_RO(temp1_input, ad7314_temperature, 0);
|
|
|
|
static struct attribute *ad7314_attrs[] = {
|
|
&sensor_dev_attr_temp1_input.dev_attr.attr,
|
|
NULL,
|
|
};
|
|
|
|
ATTRIBUTE_GROUPS(ad7314);
|
|
|
|
static int ad7314_probe(struct spi_device *spi_dev)
|
|
{
|
|
struct ad7314_data *chip;
|
|
struct device *hwmon_dev;
|
|
|
|
chip = devm_kzalloc(&spi_dev->dev, sizeof(*chip), GFP_KERNEL);
|
|
if (chip == NULL)
|
|
return -ENOMEM;
|
|
|
|
chip->spi_dev = spi_dev;
|
|
hwmon_dev = devm_hwmon_device_register_with_groups(&spi_dev->dev,
|
|
spi_dev->modalias,
|
|
chip, ad7314_groups);
|
|
return PTR_ERR_OR_ZERO(hwmon_dev);
|
|
}
|
|
|
|
static const struct spi_device_id ad7314_id[] = {
|
|
{ "adt7301", adt7301 },
|
|
{ "adt7302", adt7302 },
|
|
{ "ad7314", ad7314 },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(spi, ad7314_id);
|
|
|
|
static struct spi_driver ad7314_driver = {
|
|
.driver = {
|
|
.name = "ad7314",
|
|
},
|
|
.probe = ad7314_probe,
|
|
.id_table = ad7314_id,
|
|
};
|
|
|
|
module_spi_driver(ad7314_driver);
|
|
|
|
MODULE_AUTHOR("Sonic Zhang <sonic.zhang@analog.com>");
|
|
MODULE_DESCRIPTION("Analog Devices AD7314, ADT7301 and ADT7302 digital temperature sensor driver");
|
|
MODULE_LICENSE("GPL v2");
|