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gerrit-public.fairphone.software / kernel / msm-4.9 / 64a70c6502111a2d5bd1dd5eddfa33039aa897b7 / . / drivers / iio / pressure / ms5637.c
blob: e3ad9d39b966bdbecedcff49ef6d43e6a227aeb1 [file] [log] [blame]
Ludovic Tancerel64a70c62015-10-01 16:13:40 +0200[diff] [blame^]1/*
2 * ms5637.c - Support for Measurement-Specialties ms5637
3 * pressure & temperature sensor
4 *
5 * Copyright (c) 2015 Measurement-Specialties
6 *
7 * Licensed under the GPL-2.
8 *
9 * (7-bit I2C slave address 0x76)
10 *
11 * Datasheet:
12 * http://www.meas-spec.com/downloads/MS5637-02BA03.pdf
13 */
14#include <linux/init.h>
15#include <linux/device.h>
16#include <linux/kernel.h>
17#include <linux/stat.h>
18#include <linux/module.h>
19#include <linux/i2c.h>
20#include <linux/iio/iio.h>
21#include <linux/iio/sysfs.h>
22#include <linux/mutex.h>
23
24#include "../common/ms_sensors/ms_sensors_i2c.h"
25
26static const int ms5637_samp_freq[6] = { 960, 480, 240, 120, 60, 30 };
27/* String copy of the above const for readability purpose */
28static const char ms5637_show_samp_freq[] = "960 480 240 120 60 30";
29
30static int ms5637_read_raw(struct iio_dev *indio_dev,
31 struct iio_chan_spec const *channel, int *val,
32 int *val2, long mask)
33{
34 int ret;
35 int temperature;
36 unsigned int pressure;
37 struct ms_tp_dev *dev_data = iio_priv(indio_dev);
38
39 switch (mask) {
40 case IIO_CHAN_INFO_PROCESSED:
41 ret = ms_sensors_read_temp_and_pressure(dev_data,
42 &temperature,
43 &pressure);
44 if (ret)
45 return ret;
46
47 switch (channel->type) {
48 case IIO_TEMP: /* in milli °C */
49 *val = temperature;
50
51 return IIO_VAL_INT;
52 case IIO_PRESSURE: /* in kPa */
53 *val = pressure / 1000;
54 *val2 = (pressure % 1000) * 1000;
55
56 return IIO_VAL_INT_PLUS_MICRO;
57 default:
58 return -EINVAL;
59 }
60 case IIO_CHAN_INFO_SAMP_FREQ:
61 *val = ms5637_samp_freq[dev_data->res_index];
62
63 return IIO_VAL_INT;
64 default:
65 return -EINVAL;
66 }
67}
68
69static int ms5637_write_raw(struct iio_dev *indio_dev,
70 struct iio_chan_spec const *chan,
71 int val, int val2, long mask)
72{
73 struct ms_tp_dev *dev_data = iio_priv(indio_dev);
74 int i;
75
76 switch (mask) {
77 case IIO_CHAN_INFO_SAMP_FREQ:
78 i = ARRAY_SIZE(ms5637_samp_freq);
79 while (i-- > 0)
80 if (val == ms5637_samp_freq[i])
81 break;
82 if (i < 0)
83 return -EINVAL;
84 dev_data->res_index = i;
85
86 return 0;
87 default:
88 return -EINVAL;
89 }
90}
91
92static const struct iio_chan_spec ms5637_channels[] = {
93 {
94 .type = IIO_TEMP,
95 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
96 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
97 },
98 {
99 .type = IIO_PRESSURE,
100 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
101 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
102 }
103};
104
105static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(ms5637_show_samp_freq);
106
107static struct attribute *ms5637_attributes[] = {
108 &iio_const_attr_sampling_frequency_available.dev_attr.attr,
109 NULL,
110};
111
112static const struct attribute_group ms5637_attribute_group = {
113 .attrs = ms5637_attributes,
114};
115
116static const struct iio_info ms5637_info = {
117 .read_raw = ms5637_read_raw,
118 .write_raw = ms5637_write_raw,
119 .attrs = &ms5637_attribute_group,
120 .driver_module = THIS_MODULE,
121};
122
123static int ms5637_probe(struct i2c_client *client,
124 const struct i2c_device_id *id)
125{
126 struct ms_tp_dev *dev_data;
127 struct iio_dev *indio_dev;
128 int ret;
129
130 if (!i2c_check_functionality(client->adapter,
131 I2C_FUNC_SMBUS_READ_WORD_DATA |
132 I2C_FUNC_SMBUS_WRITE_BYTE |
133 I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
134 dev_err(&client->dev,
135 "Adapter does not support some i2c transaction\n");
136 return -ENODEV;
137 }
138
139 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*dev_data));
140 if (!indio_dev)
141 return -ENOMEM;
142
143 dev_data = iio_priv(indio_dev);
144 dev_data->client = client;
145 dev_data->res_index = 5;
146 mutex_init(&dev_data->lock);
147
148 indio_dev->info = &ms5637_info;
149 indio_dev->name = id->name;
150 indio_dev->dev.parent = &client->dev;
151 indio_dev->modes = INDIO_DIRECT_MODE;
152 indio_dev->channels = ms5637_channels;
153 indio_dev->num_channels = ARRAY_SIZE(ms5637_channels);
154
155 i2c_set_clientdata(client, indio_dev);
156
157 ret = ms_sensors_reset(client, 0x1E, 3000);
158 if (ret)
159 return ret;
160
161 ret = ms_sensors_tp_read_prom(dev_data);
162 if (ret)
163 return ret;
164
165 return devm_iio_device_register(&client->dev, indio_dev);
166}
167
168static const struct i2c_device_id ms5637_id[] = {
169 {"ms5637", 0},
170 {}
171};
172
173static struct i2c_driver ms5637_driver = {
174 .probe = ms5637_probe,
175 .id_table = ms5637_id,
176 .driver = {
177 .name = "ms5637"
178 },
179};
180
181module_i2c_driver(ms5637_driver);
182
183MODULE_DESCRIPTION("Measurement-Specialties ms5637 temperature & pressure driver");
184MODULE_AUTHOR("William Markezana <william.markezana@meas-spec.com>");
185MODULE_AUTHOR("Ludovic Tancerel <ludovic.tancerel@maplehightech.com>");
186MODULE_LICENSE("GPL v2");