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; |
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 | |
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"); |