xref: /linux/drivers/input/misc/adxl34x-i2c.c (revision 2a6b6c9a226279b4f6668450ddb21ae655558087)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * ADLX345/346 Three-Axis Digital Accelerometers (I2C Interface)
4  *
5  * Enter bugs at http://blackfin.uclinux.org/
6  *
7  * Copyright (C) 2009 Michael Hennerich, Analog Devices Inc.
8  */
9 
10 #include <linux/input.h>	/* BUS_I2C */
11 #include <linux/i2c.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/types.h>
15 #include <linux/pm.h>
16 #include "adxl34x.h"
17 
18 static int adxl34x_smbus_read(struct device *dev, unsigned char reg)
19 {
20 	struct i2c_client *client = to_i2c_client(dev);
21 
22 	return i2c_smbus_read_byte_data(client, reg);
23 }
24 
25 static int adxl34x_smbus_write(struct device *dev,
26 			       unsigned char reg, unsigned char val)
27 {
28 	struct i2c_client *client = to_i2c_client(dev);
29 
30 	return i2c_smbus_write_byte_data(client, reg, val);
31 }
32 
33 static int adxl34x_smbus_read_block(struct device *dev,
34 				    unsigned char reg, int count,
35 				    void *buf)
36 {
37 	struct i2c_client *client = to_i2c_client(dev);
38 
39 	return i2c_smbus_read_i2c_block_data(client, reg, count, buf);
40 }
41 
42 static int adxl34x_i2c_read_block(struct device *dev,
43 				  unsigned char reg, int count,
44 				  void *buf)
45 {
46 	struct i2c_client *client = to_i2c_client(dev);
47 	int ret;
48 
49 	ret = i2c_master_send(client, &reg, 1);
50 	if (ret < 0)
51 		return ret;
52 
53 	ret = i2c_master_recv(client, buf, count);
54 	if (ret < 0)
55 		return ret;
56 
57 	if (ret != count)
58 		return -EIO;
59 
60 	return 0;
61 }
62 
63 static const struct adxl34x_bus_ops adxl34x_smbus_bops = {
64 	.bustype	= BUS_I2C,
65 	.write		= adxl34x_smbus_write,
66 	.read		= adxl34x_smbus_read,
67 	.read_block	= adxl34x_smbus_read_block,
68 };
69 
70 static const struct adxl34x_bus_ops adxl34x_i2c_bops = {
71 	.bustype	= BUS_I2C,
72 	.write		= adxl34x_smbus_write,
73 	.read		= adxl34x_smbus_read,
74 	.read_block	= adxl34x_i2c_read_block,
75 };
76 
77 static int adxl34x_i2c_probe(struct i2c_client *client)
78 {
79 	struct adxl34x *ac;
80 	int error;
81 
82 	error = i2c_check_functionality(client->adapter,
83 			I2C_FUNC_SMBUS_BYTE_DATA);
84 	if (!error) {
85 		dev_err(&client->dev, "SMBUS Byte Data not Supported\n");
86 		return -EIO;
87 	}
88 
89 	ac = adxl34x_probe(&client->dev, client->irq, false,
90 			   i2c_check_functionality(client->adapter,
91 						   I2C_FUNC_SMBUS_READ_I2C_BLOCK) ?
92 				&adxl34x_smbus_bops : &adxl34x_i2c_bops);
93 	if (IS_ERR(ac))
94 		return PTR_ERR(ac);
95 
96 	i2c_set_clientdata(client, ac);
97 
98 	return 0;
99 }
100 
101 static const struct i2c_device_id adxl34x_id[] = {
102 	{ "adxl34x" },
103 	{ }
104 };
105 
106 MODULE_DEVICE_TABLE(i2c, adxl34x_id);
107 
108 static const struct of_device_id adxl34x_of_id[] = {
109 	/*
110 	 * The ADXL346 is backward-compatible with the ADXL345. Differences are
111 	 * handled by runtime detection of the device model, there's thus no
112 	 * need for listing the "adi,adxl346" compatible value explicitly.
113 	 */
114 	{ .compatible = "adi,adxl345", },
115 	/*
116 	 * Deprecated, DT nodes should use one or more of the device-specific
117 	 * compatible values "adi,adxl345" and "adi,adxl346".
118 	 */
119 	{ .compatible = "adi,adxl34x", },
120 	{ }
121 };
122 
123 MODULE_DEVICE_TABLE(of, adxl34x_of_id);
124 
125 static struct i2c_driver adxl34x_driver = {
126 	.driver = {
127 		.name = "adxl34x",
128 		.dev_groups = adxl34x_groups,
129 		.pm = pm_sleep_ptr(&adxl34x_pm),
130 		.of_match_table = adxl34x_of_id,
131 	},
132 	.probe    = adxl34x_i2c_probe,
133 	.id_table = adxl34x_id,
134 };
135 
136 module_i2c_driver(adxl34x_driver);
137 
138 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
139 MODULE_DESCRIPTION("ADXL345/346 Three-Axis Digital Accelerometer I2C Bus Driver");
140 MODULE_LICENSE("GPL");
141