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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/hwmon/ad7314.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/hwmon/ad7314.c')
-rw-r--r-- | drivers/hwmon/ad7314.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/drivers/hwmon/ad7314.c b/drivers/hwmon/ad7314.c new file mode 100644 index 000000000..8ea35932f --- /dev/null +++ b/drivers/hwmon/ad7314.c @@ -0,0 +1,136 @@ +/* + * AD7314 digital temperature sensor driver for AD7314, ADT7301 and ADT7302 + * + * Copyright 2010 Analog Devices Inc. + * + * Licensed under the GPL-2 or later. + * + * 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_show_temperature(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(temp1_input, S_IRUGO, + ad7314_show_temperature, NULL, 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"); |