1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * BME680 - I2C Driver
4  *
5  * Copyright (C) 2018 Himanshu Jha <himanshujha199640@gmail.com>
6  *
7  * 7-Bit I2C slave address is:
8  *	- 0x76 if SDO is pulled to GND
9  *	- 0x77 if SDO is pulled to VDDIO
10  *
11  * Note: SDO pin cannot be left floating otherwise I2C address
12  *	 will be undefined.
13  */
14 #include <linux/acpi.h>
15 #include <linux/i2c.h>
16 #include <linux/module.h>
17 #include <linux/regmap.h>
18 
19 #include "bme680.h"
20 
21 static int bme680_i2c_probe(struct i2c_client *client,
22 			    const struct i2c_device_id *id)
23 {
24 	struct regmap *regmap;
25 	const char *name = NULL;
26 	unsigned int val;
27 	int ret;
28 
29 	regmap = devm_regmap_init_i2c(client, &bme680_regmap_config);
30 	if (IS_ERR(regmap)) {
31 		dev_err(&client->dev, "Failed to register i2c regmap %d\n",
32 				(int)PTR_ERR(regmap));
33 		return PTR_ERR(regmap);
34 	}
35 
36 	ret = regmap_write(regmap, BME680_REG_SOFT_RESET_I2C,
37 			   BME680_CMD_SOFTRESET);
38 	if (ret < 0) {
39 		dev_err(&client->dev, "Failed to reset chip\n");
40 		return ret;
41 	}
42 
43 	ret = regmap_read(regmap, BME680_REG_CHIP_I2C_ID, &val);
44 	if (ret < 0) {
45 		dev_err(&client->dev, "Error reading I2C chip ID\n");
46 		return ret;
47 	}
48 
49 	if (val != BME680_CHIP_ID_VAL) {
50 		dev_err(&client->dev, "Wrong chip ID, got %x expected %x\n",
51 				val, BME680_CHIP_ID_VAL);
52 		return -ENODEV;
53 	}
54 
55 	if (id)
56 		name = id->name;
57 
58 	return bme680_core_probe(&client->dev, regmap, name);
59 }
60 
61 static const struct i2c_device_id bme680_i2c_id[] = {
62 	{"bme680", 0},
63 	{},
64 };
65 MODULE_DEVICE_TABLE(i2c, bme680_i2c_id);
66 
67 static const struct acpi_device_id bme680_acpi_match[] = {
68 	{"BME0680", 0},
69 	{},
70 };
71 MODULE_DEVICE_TABLE(acpi, bme680_acpi_match);
72 
73 static struct i2c_driver bme680_i2c_driver = {
74 	.driver = {
75 		.name			= "bme680_i2c",
76 		.acpi_match_table       = ACPI_PTR(bme680_acpi_match),
77 	},
78 	.probe = bme680_i2c_probe,
79 	.id_table = bme680_i2c_id,
80 };
81 module_i2c_driver(bme680_i2c_driver);
82 
83 MODULE_AUTHOR("Himanshu Jha <himanshujha199640@gmail.com>");
84 MODULE_DESCRIPTION("BME680 I2C driver");
85 MODULE_LICENSE("GPL v2");
86