blob: 202c1fbb3407a7973d8ff993813dbf38dd802d24 [file] [log] [blame]
Jonathan Cameron4f3a6592011-09-29 12:50:04 -04001/*
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>
Rasmus Villemoes984faa12015-01-22 23:44:13 +010019#include <linux/bitops.h>
Jonathan Cameron4f3a6592011-09-29 12:50:04 -040020
21/*
Jonathan Cameron4f3a6592011-09-29 12:50:04 -040022 * AD7314 temperature masks
23 */
Jonathan Cameron4f3a6592011-09-29 12:50:04 -040024#define AD7314_TEMP_MASK 0x7FE0
Guenter Roeck1137a9a2012-04-22 00:22:00 -040025#define AD7314_TEMP_SHIFT 5
Jonathan Cameron4f3a6592011-09-29 12:50:04 -040026
27/*
28 * ADT7301 and ADT7302 temperature masks
29 */
Jonathan Cameron4f3a6592011-09-29 12:50:04 -040030#define ADT7301_TEMP_MASK 0x3FFF
31
32enum ad7314_variant {
33 adt7301,
34 adt7302,
35 ad7314,
36};
37
38struct ad7314_data {
39 struct spi_device *spi_dev;
40 struct device *hwmon_dev;
41 u16 rx ____cacheline_aligned;
42};
43
Guenter Roeckeae14152012-04-20 11:39:17 -040044static int ad7314_spi_read(struct ad7314_data *chip)
Jonathan Cameron4f3a6592011-09-29 12:50:04 -040045{
46 int ret;
47
48 ret = spi_read(chip->spi_dev, (u8 *)&chip->rx, sizeof(chip->rx));
49 if (ret < 0) {
50 dev_err(&chip->spi_dev->dev, "SPI read error\n");
51 return ret;
52 }
53
Guenter Roeckeae14152012-04-20 11:39:17 -040054 return be16_to_cpu(chip->rx);
Jonathan Cameron4f3a6592011-09-29 12:50:04 -040055}
56
57static ssize_t ad7314_show_temperature(struct device *dev,
58 struct device_attribute *attr,
59 char *buf)
60{
61 struct ad7314_data *chip = dev_get_drvdata(dev);
62 s16 data;
63 int ret;
64
Guenter Roeckeae14152012-04-20 11:39:17 -040065 ret = ad7314_spi_read(chip);
Jonathan Cameron4f3a6592011-09-29 12:50:04 -040066 if (ret < 0)
67 return ret;
68 switch (spi_get_device_id(chip->spi_dev)->driver_data) {
69 case ad7314:
Guenter Roeck1137a9a2012-04-22 00:22:00 -040070 data = (ret & AD7314_TEMP_MASK) >> AD7314_TEMP_SHIFT;
Rasmus Villemoes984faa12015-01-22 23:44:13 +010071 data = sign_extend32(data, 9);
Jonathan Cameron4f3a6592011-09-29 12:50:04 -040072
73 return sprintf(buf, "%d\n", 250 * data);
74 case adt7301:
75 case adt7302:
76 /*
77 * Documented as a 13 bit twos complement register
78 * with a sign bit - which is a 14 bit 2's complement
79 * register. 1lsb - 31.25 milli degrees centigrade
80 */
Guenter Roeckeae14152012-04-20 11:39:17 -040081 data = ret & ADT7301_TEMP_MASK;
Rasmus Villemoes984faa12015-01-22 23:44:13 +010082 data = sign_extend32(data, 13);
Jonathan Cameron4f3a6592011-09-29 12:50:04 -040083
84 return sprintf(buf, "%d\n",
85 DIV_ROUND_CLOSEST(data * 3125, 100));
86 default:
87 return -EINVAL;
88 }
89}
90
Guenter Roeck3ceefe42012-09-11 13:43:17 -070091static ssize_t ad7314_show_name(struct device *dev,
92 struct device_attribute *devattr, char *buf)
93{
94 return sprintf(buf, "%s\n", to_spi_device(dev)->modalias);
95}
96
97static DEVICE_ATTR(name, S_IRUGO, ad7314_show_name, NULL);
Jonathan Cameron4f3a6592011-09-29 12:50:04 -040098static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO,
99 ad7314_show_temperature, NULL, 0);
100
101static struct attribute *ad7314_attributes[] = {
Guenter Roeck3ceefe42012-09-11 13:43:17 -0700102 &dev_attr_name.attr,
Jonathan Cameron4f3a6592011-09-29 12:50:04 -0400103 &sensor_dev_attr_temp1_input.dev_attr.attr,
104 NULL,
105};
106
107static const struct attribute_group ad7314_group = {
108 .attrs = ad7314_attributes,
109};
110
Bill Pemberton6c931ae2012-11-19 13:22:35 -0500111static int ad7314_probe(struct spi_device *spi_dev)
Jonathan Cameron4f3a6592011-09-29 12:50:04 -0400112{
113 int ret;
114 struct ad7314_data *chip;
115
Guenter Roeckbe923042012-06-02 09:57:57 -0700116 chip = devm_kzalloc(&spi_dev->dev, sizeof(*chip), GFP_KERNEL);
117 if (chip == NULL)
118 return -ENOMEM;
119
Jingoo Handebe5972013-04-05 10:51:29 +0900120 spi_set_drvdata(spi_dev, chip);
Jonathan Cameron4f3a6592011-09-29 12:50:04 -0400121
122 ret = sysfs_create_group(&spi_dev->dev.kobj, &ad7314_group);
123 if (ret < 0)
Guenter Roeckbe923042012-06-02 09:57:57 -0700124 return ret;
125
Jonathan Cameron4f3a6592011-09-29 12:50:04 -0400126 chip->hwmon_dev = hwmon_device_register(&spi_dev->dev);
127 if (IS_ERR(chip->hwmon_dev)) {
128 ret = PTR_ERR(chip->hwmon_dev);
129 goto error_remove_group;
130 }
Graeme Smechere16de912012-04-03 19:42:21 -0400131 chip->spi_dev = spi_dev;
Jonathan Cameron4f3a6592011-09-29 12:50:04 -0400132
133 return 0;
134error_remove_group:
135 sysfs_remove_group(&spi_dev->dev.kobj, &ad7314_group);
Jonathan Cameron4f3a6592011-09-29 12:50:04 -0400136 return ret;
137}
138
Bill Pemberton281dfd02012-11-19 13:25:51 -0500139static int ad7314_remove(struct spi_device *spi_dev)
Jonathan Cameron4f3a6592011-09-29 12:50:04 -0400140{
Jingoo Handebe5972013-04-05 10:51:29 +0900141 struct ad7314_data *chip = spi_get_drvdata(spi_dev);
Jonathan Cameron4f3a6592011-09-29 12:50:04 -0400142
143 hwmon_device_unregister(chip->hwmon_dev);
144 sysfs_remove_group(&spi_dev->dev.kobj, &ad7314_group);
Jonathan Cameron4f3a6592011-09-29 12:50:04 -0400145
146 return 0;
147}
148
149static const struct spi_device_id ad7314_id[] = {
150 { "adt7301", adt7301 },
151 { "adt7302", adt7302 },
152 { "ad7314", ad7314 },
153 { }
154};
155MODULE_DEVICE_TABLE(spi, ad7314_id);
156
157static struct spi_driver ad7314_driver = {
158 .driver = {
159 .name = "ad7314",
Jonathan Cameron4f3a6592011-09-29 12:50:04 -0400160 },
161 .probe = ad7314_probe,
Bill Pemberton9e5e9b72012-11-19 13:21:20 -0500162 .remove = ad7314_remove,
Jonathan Cameron4f3a6592011-09-29 12:50:04 -0400163 .id_table = ad7314_id,
164};
165
Axel Lin91efffe2012-01-20 15:53:47 +0800166module_spi_driver(ad7314_driver);
Jonathan Cameron4f3a6592011-09-29 12:50:04 -0400167
168MODULE_AUTHOR("Sonic Zhang <sonic.zhang@analog.com>");
Guenter Roeckb55f3752013-01-10 10:01:24 -0800169MODULE_DESCRIPTION("Analog Devices AD7314, ADT7301 and ADT7302 digital temperature sensor driver");
Jonathan Cameron4f3a6592011-09-29 12:50:04 -0400170MODULE_LICENSE("GPL v2");