xref: /openbmc/linux/drivers/iio/pressure/ms5637.c (revision 6c9111bc)
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/mod_devicetable.h>
26 #include <linux/i2c.h>
27 #include <linux/iio/iio.h>
28 #include <linux/iio/sysfs.h>
29 #include <linux/mutex.h>
30 
31 #include "../common/ms_sensors/ms_sensors_i2c.h"
32 
33 static const int ms5637_samp_freq[6] = { 960, 480, 240, 120, 60, 30 };
34 /* String copy of the above const for readability purpose */
35 static const char ms5637_show_samp_freq[] = "960 480 240 120 60 30";
36 
37 static int ms5637_read_raw(struct iio_dev *indio_dev,
38 			   struct iio_chan_spec const *channel, int *val,
39 			   int *val2, long mask)
40 {
41 	int ret;
42 	int temperature;
43 	unsigned int pressure;
44 	struct ms_tp_dev *dev_data = iio_priv(indio_dev);
45 
46 	switch (mask) {
47 	case IIO_CHAN_INFO_PROCESSED:
48 		ret = ms_sensors_read_temp_and_pressure(dev_data,
49 							&temperature,
50 							&pressure);
51 		if (ret)
52 			return ret;
53 
54 		switch (channel->type) {
55 		case IIO_TEMP:	/* in milli °C */
56 			*val = temperature;
57 
58 			return IIO_VAL_INT;
59 		case IIO_PRESSURE:	/* in kPa */
60 			*val = pressure / 1000;
61 			*val2 = (pressure % 1000) * 1000;
62 
63 			return IIO_VAL_INT_PLUS_MICRO;
64 		default:
65 			return -EINVAL;
66 		}
67 	case IIO_CHAN_INFO_SAMP_FREQ:
68 		*val = ms5637_samp_freq[dev_data->res_index];
69 
70 		return IIO_VAL_INT;
71 	default:
72 		return -EINVAL;
73 	}
74 }
75 
76 static int ms5637_write_raw(struct iio_dev *indio_dev,
77 			    struct iio_chan_spec const *chan,
78 			    int val, int val2, long mask)
79 {
80 	struct ms_tp_dev *dev_data = iio_priv(indio_dev);
81 	int i;
82 
83 	switch (mask) {
84 	case IIO_CHAN_INFO_SAMP_FREQ:
85 		i = ARRAY_SIZE(ms5637_samp_freq);
86 		while (i-- > 0)
87 			if (val == ms5637_samp_freq[i])
88 				break;
89 		if (i < 0)
90 			return -EINVAL;
91 		dev_data->res_index = i;
92 
93 		return 0;
94 	default:
95 		return -EINVAL;
96 	}
97 }
98 
99 static const struct iio_chan_spec ms5637_channels[] = {
100 	{
101 		.type = IIO_TEMP,
102 		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
103 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
104 	},
105 	{
106 		.type = IIO_PRESSURE,
107 		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
108 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
109 	}
110 };
111 
112 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(ms5637_show_samp_freq);
113 
114 static struct attribute *ms5637_attributes[] = {
115 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
116 	NULL,
117 };
118 
119 static const struct attribute_group ms5637_attribute_group = {
120 	.attrs = ms5637_attributes,
121 };
122 
123 static const struct iio_info ms5637_info = {
124 	.read_raw = ms5637_read_raw,
125 	.write_raw = ms5637_write_raw,
126 	.attrs = &ms5637_attribute_group,
127 };
128 
129 static int ms5637_probe(struct i2c_client *client,
130 			const struct i2c_device_id *id)
131 {
132 	struct ms_tp_dev *dev_data;
133 	struct iio_dev *indio_dev;
134 	int ret;
135 
136 	if (!i2c_check_functionality(client->adapter,
137 				     I2C_FUNC_SMBUS_READ_WORD_DATA |
138 				     I2C_FUNC_SMBUS_WRITE_BYTE |
139 				     I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
140 		dev_err(&client->dev,
141 			"Adapter does not support some i2c transaction\n");
142 		return -EOPNOTSUPP;
143 	}
144 
145 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*dev_data));
146 	if (!indio_dev)
147 		return -ENOMEM;
148 
149 	dev_data = iio_priv(indio_dev);
150 	dev_data->client = client;
151 	dev_data->res_index = 5;
152 	mutex_init(&dev_data->lock);
153 
154 	indio_dev->info = &ms5637_info;
155 	indio_dev->name = id->name;
156 	indio_dev->modes = INDIO_DIRECT_MODE;
157 	indio_dev->channels = ms5637_channels;
158 	indio_dev->num_channels = ARRAY_SIZE(ms5637_channels);
159 
160 	i2c_set_clientdata(client, indio_dev);
161 
162 	ret = ms_sensors_reset(client, 0x1E, 3000);
163 	if (ret)
164 		return ret;
165 
166 	ret = ms_sensors_tp_read_prom(dev_data);
167 	if (ret)
168 		return ret;
169 
170 	return devm_iio_device_register(&client->dev, indio_dev);
171 }
172 
173 static const struct i2c_device_id ms5637_id[] = {
174 	{"ms5637", 0},
175 	{"ms5805", 0},
176 	{"ms5837", 0},
177 	{"ms8607-temppressure", 0},
178 	{}
179 };
180 MODULE_DEVICE_TABLE(i2c, ms5637_id);
181 
182 static const struct of_device_id ms5637_of_match[] = {
183 	{ .compatible = "meas,ms5637", },
184 	{ .compatible = "meas,ms5805", },
185 	{ .compatible = "meas,ms5837", },
186 	{ .compatible = "meas,ms8607-temppressure", },
187 	{ },
188 };
189 MODULE_DEVICE_TABLE(of, ms5637_of_match);
190 
191 static struct i2c_driver ms5637_driver = {
192 	.probe = ms5637_probe,
193 	.id_table = ms5637_id,
194 	.driver = {
195 		   .name = "ms5637",
196 		   .of_match_table = ms5637_of_match,
197 		   },
198 };
199 
200 module_i2c_driver(ms5637_driver);
201 
202 MODULE_DESCRIPTION("Measurement-Specialties ms5637 temperature & pressure driver");
203 MODULE_AUTHOR("William Markezana <william.markezana@meas-spec.com>");
204 MODULE_AUTHOR("Ludovic Tancerel <ludovic.tancerel@maplehightech.com>");
205 MODULE_LICENSE("GPL v2");
206