1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * MS5611 pressure and temperature sensor driver (I2C bus) |
4 | * |
5 | * Copyright (c) Tomasz Duszynski <tduszyns@gmail.com> |
6 | * |
7 | * 7-bit I2C slave addresses: |
8 | * |
9 | * 0x77 (CSB pin low) |
10 | * 0x76 (CSB pin high) |
11 | * |
12 | */ |
13 | |
14 | #include <linux/delay.h> |
15 | #include <linux/i2c.h> |
16 | #include <linux/module.h> |
17 | #include <linux/mod_devicetable.h> |
18 | |
19 | #include <asm/unaligned.h> |
20 | |
21 | #include "ms5611.h" |
22 | |
23 | static int ms5611_i2c_reset(struct ms5611_state *st) |
24 | { |
25 | return i2c_smbus_write_byte(client: st->client, MS5611_RESET); |
26 | } |
27 | |
28 | static int ms5611_i2c_read_prom_word(struct ms5611_state *st, int index, |
29 | u16 *word) |
30 | { |
31 | int ret; |
32 | |
33 | ret = i2c_smbus_read_word_swapped(client: st->client, |
34 | MS5611_READ_PROM_WORD + (index << 1)); |
35 | if (ret < 0) |
36 | return ret; |
37 | |
38 | *word = ret; |
39 | |
40 | return 0; |
41 | } |
42 | |
43 | static int ms5611_i2c_read_adc(struct ms5611_state *st, s32 *val) |
44 | { |
45 | int ret; |
46 | u8 buf[3]; |
47 | |
48 | ret = i2c_smbus_read_i2c_block_data(client: st->client, MS5611_READ_ADC, |
49 | length: 3, values: buf); |
50 | if (ret < 0) |
51 | return ret; |
52 | |
53 | *val = get_unaligned_be24(p: &buf[0]); |
54 | |
55 | return 0; |
56 | } |
57 | |
58 | static int ms5611_i2c_read_adc_temp_and_pressure(struct ms5611_state *st, |
59 | s32 *temp, s32 *pressure) |
60 | { |
61 | int ret; |
62 | const struct ms5611_osr *osr = st->temp_osr; |
63 | |
64 | ret = i2c_smbus_write_byte(client: st->client, value: osr->cmd); |
65 | if (ret < 0) |
66 | return ret; |
67 | |
68 | usleep_range(min: osr->conv_usec, max: osr->conv_usec + (osr->conv_usec / 10UL)); |
69 | ret = ms5611_i2c_read_adc(st, val: temp); |
70 | if (ret < 0) |
71 | return ret; |
72 | |
73 | osr = st->pressure_osr; |
74 | ret = i2c_smbus_write_byte(client: st->client, value: osr->cmd); |
75 | if (ret < 0) |
76 | return ret; |
77 | |
78 | usleep_range(min: osr->conv_usec, max: osr->conv_usec + (osr->conv_usec / 10UL)); |
79 | return ms5611_i2c_read_adc(st, val: pressure); |
80 | } |
81 | |
82 | static int ms5611_i2c_probe(struct i2c_client *client) |
83 | { |
84 | const struct i2c_device_id *id = i2c_client_get_device_id(client); |
85 | struct ms5611_state *st; |
86 | struct iio_dev *indio_dev; |
87 | |
88 | if (!i2c_check_functionality(adap: client->adapter, |
89 | I2C_FUNC_SMBUS_WRITE_BYTE | |
90 | I2C_FUNC_SMBUS_READ_WORD_DATA | |
91 | I2C_FUNC_SMBUS_READ_I2C_BLOCK)) |
92 | return -EOPNOTSUPP; |
93 | |
94 | indio_dev = devm_iio_device_alloc(parent: &client->dev, sizeof_priv: sizeof(*st)); |
95 | if (!indio_dev) |
96 | return -ENOMEM; |
97 | |
98 | st = iio_priv(indio_dev); |
99 | i2c_set_clientdata(client, data: indio_dev); |
100 | st->reset = ms5611_i2c_reset; |
101 | st->read_prom_word = ms5611_i2c_read_prom_word; |
102 | st->read_adc_temp_and_pressure = ms5611_i2c_read_adc_temp_and_pressure; |
103 | st->client = client; |
104 | |
105 | return ms5611_probe(indio_dev, dev: &client->dev, name: id->name, type: id->driver_data); |
106 | } |
107 | |
108 | static const struct of_device_id ms5611_i2c_matches[] = { |
109 | { .compatible = "meas,ms5611" }, |
110 | { .compatible = "meas,ms5607" }, |
111 | { } |
112 | }; |
113 | MODULE_DEVICE_TABLE(of, ms5611_i2c_matches); |
114 | |
115 | static const struct i2c_device_id ms5611_id[] = { |
116 | { "ms5611" , MS5611 }, |
117 | { "ms5607" , MS5607 }, |
118 | { } |
119 | }; |
120 | MODULE_DEVICE_TABLE(i2c, ms5611_id); |
121 | |
122 | static struct i2c_driver ms5611_driver = { |
123 | .driver = { |
124 | .name = "ms5611" , |
125 | .of_match_table = ms5611_i2c_matches, |
126 | }, |
127 | .id_table = ms5611_id, |
128 | .probe = ms5611_i2c_probe, |
129 | }; |
130 | module_i2c_driver(ms5611_driver); |
131 | |
132 | MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>" ); |
133 | MODULE_DESCRIPTION("MS5611 i2c driver" ); |
134 | MODULE_LICENSE("GPL v2" ); |
135 | MODULE_IMPORT_NS(IIO_MS5611); |
136 | |