[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / hwmon / ad7314.c

/*
 * 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>

/*
 * 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;
	struct device		*hwmon_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 = (data << 6) >> 6;

		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 = (data << 2) >> 2;

		return sprintf(buf, "%d\n",
			       DIV_ROUND_CLOSEST(data * 3125, 100));
	default:
		return -EINVAL;
	}
}

static ssize_t ad7314_show_name(struct device *dev,
				struct device_attribute *devattr, char *buf)
{
	return sprintf(buf, "%s\n", to_spi_device(dev)->modalias);
}

static DEVICE_ATTR(name, S_IRUGO, ad7314_show_name, NULL);
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO,
			  ad7314_show_temperature, NULL, 0);

static struct attribute *ad7314_attributes[] = {
	&dev_attr_name.attr,
	&sensor_dev_attr_temp1_input.dev_attr.attr,
	NULL,
};

static const struct attribute_group ad7314_group = {
	.attrs = ad7314_attributes,
};

static int ad7314_probe(struct spi_device *spi_dev)
{
	int ret;
	struct ad7314_data *chip;

	chip = devm_kzalloc(&spi_dev->dev, sizeof(*chip), GFP_KERNEL);
	if (chip == NULL)
		return -ENOMEM;

	spi_set_drvdata(spi_dev, chip);

	ret = sysfs_create_group(&spi_dev->dev.kobj, &ad7314_group);
	if (ret < 0)
		return ret;

	chip->hwmon_dev = hwmon_device_register(&spi_dev->dev);
	if (IS_ERR(chip->hwmon_dev)) {
		ret = PTR_ERR(chip->hwmon_dev);
		goto error_remove_group;
	}
	chip->spi_dev = spi_dev;

	return 0;
error_remove_group:
	sysfs_remove_group(&spi_dev->dev.kobj, &ad7314_group);
	return ret;
}

static int ad7314_remove(struct spi_device *spi_dev)
{
	struct ad7314_data *chip = spi_get_drvdata(spi_dev);

	hwmon_device_unregister(chip->hwmon_dev);
	sysfs_remove_group(&spi_dev->dev.kobj, &ad7314_group);

	return 0;
}

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",
		.owner = THIS_MODULE,
	},
	.probe = ad7314_probe,
	.remove = ad7314_remove,
	.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");
Commit	Line	Data
4f3a6595 JC	1	/*
	2	* AD7314 digital temperature sensor driver for AD7314, ADT7301 and ADT7302
	3	*
	4	* Copyright 2010 Analog Devices Inc.
	5	*
	6	* Licensed under the GPL-2 or later.
	7	*
	8	* Conversion to hwmon from IIO done by Jonathan Cameron <jic23@cam.ac.uk>
	9	*/
	10	#include <linux/device.h>
	11	#include <linux/kernel.h>
	12	#include <linux/slab.h>
	13	#include <linux/sysfs.h>
	14	#include <linux/spi/spi.h>
	15	#include <linux/module.h>
	16	#include <linux/err.h>
	17	#include <linux/hwmon.h>
	18	#include <linux/hwmon-sysfs.h>
	19
4f3a6595 JC	20	/*
	21	* AD7314 temperature masks
	22	*/
4f3a6595	23	#define AD7314_TEMP_MASK 0x7FE0
1137a9a6	24	#define AD7314_TEMP_SHIFT 5
4f3a6595 JC	25
	26	/*
	27	* ADT7301 and ADT7302 temperature masks
	28	*/
4f3a6595 JC	29	#define ADT7301_TEMP_MASK 0x3FFF
	30
	31	enum ad7314_variant {
	32	adt7301,
	33	adt7302,
	34	ad7314,
	35	};
	36
	37	struct ad7314_data {
	38	struct spi_device *spi_dev;
	39	struct device *hwmon_dev;
	40	u16 rx ____cacheline_aligned;
	41	};
	42
eae1415d	43	static int ad7314_spi_read(struct ad7314_data *chip)
4f3a6595 JC	44	{
	45	int ret;
	46
	47	ret = spi_read(chip->spi_dev, (u8 *)&chip->rx, sizeof(chip->rx));
	48	if (ret < 0) {
	49	dev_err(&chip->spi_dev->dev, "SPI read error\n");
	50	return ret;
	51	}
	52
eae1415d	53	return be16_to_cpu(chip->rx);
4f3a6595 JC	54	}
	55
	56	static ssize_t ad7314_show_temperature(struct device *dev,
	57	struct device_attribute *attr,
	58	char *buf)
	59	{
	60	struct ad7314_data *chip = dev_get_drvdata(dev);
	61	s16 data;
	62	int ret;
	63
eae1415d	64	ret = ad7314_spi_read(chip);
4f3a6595 JC	65	if (ret < 0)
	66	return ret;
	67	switch (spi_get_device_id(chip->spi_dev)->driver_data) {
	68	case ad7314:
1137a9a6	69	data = (ret & AD7314_TEMP_MASK) >> AD7314_TEMP_SHIFT;
4f3a6595 JC	70	data = (data << 6) >> 6;
	71
	72	return sprintf(buf, "%d\n", 250 * data);
	73	case adt7301:
	74	case adt7302:
	75	/*
	76	* Documented as a 13 bit twos complement register
	77	* with a sign bit - which is a 14 bit 2's complement
	78	* register. 1lsb - 31.25 milli degrees centigrade
	79	*/
eae1415d	80	data = ret & ADT7301_TEMP_MASK;
4f3a6595 JC	81	data = (data << 2) >> 2;
	82
	83	return sprintf(buf, "%d\n",
	84	DIV_ROUND_CLOSEST(data * 3125, 100));
	85	default:
	86	return -EINVAL;
	87	}
	88	}
	89
3ceefe43 GR	90	static ssize_t ad7314_show_name(struct device *dev,
	91	struct device_attribute devattr, char buf)
	92	{
	93	return sprintf(buf, "%s\n", to_spi_device(dev)->modalias);
	94	}
	95
	96	static DEVICE_ATTR(name, S_IRUGO, ad7314_show_name, NULL);
4f3a6595 JC	97	static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO,
	98	ad7314_show_temperature, NULL, 0);
	99
	100	static struct attribute *ad7314_attributes[] = {
3ceefe43	101	&dev_attr_name.attr,
4f3a6595 JC	102	&sensor_dev_attr_temp1_input.dev_attr.attr,
	103	NULL,
	104	};
	105
	106	static const struct attribute_group ad7314_group = {
	107	.attrs = ad7314_attributes,
	108	};
	109
6c931ae1	110	static int ad7314_probe(struct spi_device *spi_dev)
4f3a6595 JC	111	{
	112	int ret;
	113	struct ad7314_data *chip;
	114
be923040 GR	115	chip = devm_kzalloc(&spi_dev->dev, sizeof(*chip), GFP_KERNEL);
	116	if (chip == NULL)
	117	return -ENOMEM;
	118
debe597c	119	spi_set_drvdata(spi_dev, chip);
4f3a6595 JC	120
	121	ret = sysfs_create_group(&spi_dev->dev.kobj, &ad7314_group);
	122	if (ret < 0)
be923040 GR	123	return ret;
be923040 GR	124
4f3a6595 JC	125	chip->hwmon_dev = hwmon_device_register(&spi_dev->dev);
	126	if (IS_ERR(chip->hwmon_dev)) {
	127	ret = PTR_ERR(chip->hwmon_dev);
	128	goto error_remove_group;
	129	}
e16de913	130	chip->spi_dev = spi_dev;
4f3a6595 JC	131
	132	return 0;
	133	error_remove_group:
	134	sysfs_remove_group(&spi_dev->dev.kobj, &ad7314_group);
4f3a6595 JC	135	return ret;
	136	}
	137
281dfd0b	138	static int ad7314_remove(struct spi_device *spi_dev)
4f3a6595	139	{
debe597c	140	struct ad7314_data *chip = spi_get_drvdata(spi_dev);
4f3a6595 JC	141
	142	hwmon_device_unregister(chip->hwmon_dev);
	143	sysfs_remove_group(&spi_dev->dev.kobj, &ad7314_group);
4f3a6595 JC	144
	145	return 0;
	146	}
	147
	148	static const struct spi_device_id ad7314_id[] = {
	149	{ "adt7301", adt7301 },
	150	{ "adt7302", adt7302 },
	151	{ "ad7314", ad7314 },
	152	{ }
	153	};
	154	MODULE_DEVICE_TABLE(spi, ad7314_id);
	155
	156	static struct spi_driver ad7314_driver = {
	157	.driver = {
	158	.name = "ad7314",
4f3a6595 JC	159	.owner = THIS_MODULE,
	160	},
	161	.probe = ad7314_probe,
9e5e9b7a	162	.remove = ad7314_remove,
4f3a6595 JC	163	.id_table = ad7314_id,
	164	};
	165
91efffe2	166	module_spi_driver(ad7314_driver);
4f3a6595 JC	167
4f3a6595 JC	168	MODULE_AUTHOR("Sonic Zhang <sonic.zhang@analog.com>");
b55f3757	169	MODULE_DESCRIPTION("Analog Devices AD7314, ADT7301 and ADT7302 digital temperature sensor driver");
4f3a6595	170	MODULE_LICENSE("GPL v2");