xref: /openbmc/linux/drivers/iio/pressure/ms5637.c (revision 29c37341)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ms5637.c - Support for Measurement-Specialties MS5637, MS5805
4  *            MS5837 and MS8607 pressure & temperature sensor
5  *
6  * Copyright (c) 2015 Measurement-Specialties
7  *
8  * (7-bit I2C slave address 0x76)
9  *
10  * Datasheet:
11  *  http://www.meas-spec.com/downloads/MS5637-02BA03.pdf
12  * Datasheet:
13  *  http://www.meas-spec.com/downloads/MS5805-02BA01.pdf
14  * Datasheet:
15  *  http://www.meas-spec.com/downloads/MS5837-30BA.pdf
16  * Datasheet:
17  *  http://www.meas-spec.com/downloads/MS8607-02BA01.pdf
18  */
19 
20 #include <linux/init.h>
21 #include <linux/device.h>
22 #include <linux/kernel.h>
23 #include <linux/stat.h>
24 #include <linux/module.h>
25 #include <linux/i2c.h>
26 #include <linux/iio/iio.h>
27 #include <linux/iio/sysfs.h>
28 #include <linux/mutex.h>
29 
30 #include "../common/ms_sensors/ms_sensors_i2c.h"
31 
32 static const int ms5637_samp_freq[6] = { 960, 480, 240, 120, 60, 30 };
33 /* String copy of the above const for readability purpose */
34 static const char ms5637_show_samp_freq[] = "960 480 240 120 60 30";
35 
36 static int ms5637_read_raw(struct iio_dev *indio_dev,
37 			   struct iio_chan_spec const *channel, int *val,
38 			   int *val2, long mask)
39 {
40 	int ret;
41 	int temperature;
42 	unsigned int pressure;
43 	struct ms_tp_dev *dev_data = iio_priv(indio_dev);
44 
45 	switch (mask) {
46 	case IIO_CHAN_INFO_PROCESSED:
47 		ret = ms_sensors_read_temp_and_pressure(dev_data,
48 							&temperature,
49 							&pressure);
50 		if (ret)
51 			return ret;
52 
53 		switch (channel->type) {
54 		case IIO_TEMP:	/* in milli °C */
55 			*val = temperature;
56 
57 			return IIO_VAL_INT;
58 		case IIO_PRESSURE:	/* in kPa */
59 			*val = pressure / 1000;
60 			*val2 = (pressure % 1000) * 1000;
61 
62 			return IIO_VAL_INT_PLUS_MICRO;
63 		default:
64 			return -EINVAL;
65 		}
66 	case IIO_CHAN_INFO_SAMP_FREQ:
67 		*val = ms5637_samp_freq[dev_data->res_index];
68 
69 		return IIO_VAL_INT;
70 	default:
71 		return -EINVAL;
72 	}
73 }
74 
75 static int ms5637_write_raw(struct iio_dev *indio_dev,
76 			    struct iio_chan_spec const *chan,
77 			    int val, int val2, long mask)
78 {
79 	struct ms_tp_dev *dev_data = iio_priv(indio_dev);
80 	int i;
81 
82 	switch (mask) {
83 	case IIO_CHAN_INFO_SAMP_FREQ:
84 		i = ARRAY_SIZE(ms5637_samp_freq);
85 		while (i-- > 0)
86 			if (val == ms5637_samp_freq[i])
87 				break;
88 		if (i < 0)
89 			return -EINVAL;
90 		dev_data->res_index = i;
91 
92 		return 0;
93 	default:
94 		return -EINVAL;
95 	}
96 }
97 
98 static const struct iio_chan_spec ms5637_channels[] = {
99 	{
100 		.type = IIO_TEMP,
101 		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
102 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
103 	},
104 	{
105 		.type = IIO_PRESSURE,
106 		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
107 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
108 	}
109 };
110 
111 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(ms5637_show_samp_freq);
112 
113 static struct attribute *ms5637_attributes[] = {
114 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
115 	NULL,
116 };
117 
118 static const struct attribute_group ms5637_attribute_group = {
119 	.attrs = ms5637_attributes,
120 };
121 
122 static const struct iio_info ms5637_info = {
123 	.read_raw = ms5637_read_raw,
124 	.write_raw = ms5637_write_raw,
125 	.attrs = &ms5637_attribute_group,
126 };
127 
128 static int ms5637_probe(struct i2c_client *client,
129 			const struct i2c_device_id *id)
130 {
131 	struct ms_tp_dev *dev_data;
132 	struct iio_dev *indio_dev;
133 	int ret;
134 
135 	if (!i2c_check_functionality(client->adapter,
136 				     I2C_FUNC_SMBUS_READ_WORD_DATA |
137 				     I2C_FUNC_SMBUS_WRITE_BYTE |
138 				     I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
139 		dev_err(&client->dev,
140 			"Adapter does not support some i2c transaction\n");
141 		return -EOPNOTSUPP;
142 	}
143 
144 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*dev_data));
145 	if (!indio_dev)
146 		return -ENOMEM;
147 
148 	dev_data = iio_priv(indio_dev);
149 	dev_data->client = client;
150 	dev_data->res_index = 5;
151 	mutex_init(&dev_data->lock);
152 
153 	indio_dev->info = &ms5637_info;
154 	indio_dev->name = id->name;
155 	indio_dev->modes = INDIO_DIRECT_MODE;
156 	indio_dev->channels = ms5637_channels;
157 	indio_dev->num_channels = ARRAY_SIZE(ms5637_channels);
158 
159 	i2c_set_clientdata(client, indio_dev);
160 
161 	ret = ms_sensors_reset(client, 0x1E, 3000);
162 	if (ret)
163 		return ret;
164 
165 	ret = ms_sensors_tp_read_prom(dev_data);
166 	if (ret)
167 		return ret;
168 
169 	return devm_iio_device_register(&client->dev, indio_dev);
170 }
171 
172 static const struct i2c_device_id ms5637_id[] = {
173 	{"ms5637", 0},
174 	{"ms5805", 0},
175 	{"ms5837", 0},
176 	{"ms8607-temppressure", 0},
177 	{}
178 };
179 MODULE_DEVICE_TABLE(i2c, ms5637_id);
180 
181 static const struct of_device_id ms5637_of_match[] = {
182 	{ .compatible = "meas,ms5637", },
183 	{ .compatible = "meas,ms5805", },
184 	{ .compatible = "meas,ms5837", },
185 	{ .compatible = "meas,ms8607-temppressure", },
186 	{ },
187 };
188 MODULE_DEVICE_TABLE(of, ms5637_of_match);
189 
190 static struct i2c_driver ms5637_driver = {
191 	.probe = ms5637_probe,
192 	.id_table = ms5637_id,
193 	.driver = {
194 		   .name = "ms5637",
195 		   .of_match_table = of_match_ptr(ms5637_of_match),
196 		   },
197 };
198 
199 module_i2c_driver(ms5637_driver);
200 
201 MODULE_DESCRIPTION("Measurement-Specialties ms5637 temperature & pressure driver");
202 MODULE_AUTHOR("William Markezana <william.markezana@meas-spec.com>");
203 MODULE_AUTHOR("Ludovic Tancerel <ludovic.tancerel@maplehightech.com>");
204 MODULE_LICENSE("GPL v2");
205