xref: /openbmc/linux/drivers/iio/accel/adxl345_spi.c (revision 4aea96f4)
1 /*
2  * ADXL345 3-Axis Digital Accelerometer SPI driver
3  *
4  * Copyright (c) 2017 Eva Rachel Retuya <eraretuya@gmail.com>
5  *
6  * This file is subject to the terms and conditions of version 2 of
7  * the GNU General Public License. See the file COPYING in the main
8  * directory of this archive for more details.
9  */
10 
11 #include <linux/module.h>
12 #include <linux/regmap.h>
13 #include <linux/spi/spi.h>
14 
15 #include "adxl345.h"
16 
17 #define ADXL345_MAX_SPI_FREQ_HZ		5000000
18 
19 static const struct regmap_config adxl345_spi_regmap_config = {
20 	.reg_bits = 8,
21 	.val_bits = 8,
22 	 /* Setting bits 7 and 6 enables multiple-byte read */
23 	.read_flag_mask = BIT(7) | BIT(6),
24 };
25 
26 static int adxl345_spi_probe(struct spi_device *spi)
27 {
28 	const struct spi_device_id *id = spi_get_device_id(spi);
29 	struct regmap *regmap;
30 
31 	/* Bail out if max_speed_hz exceeds 5 MHz */
32 	if (spi->max_speed_hz > ADXL345_MAX_SPI_FREQ_HZ) {
33 		dev_err(&spi->dev, "SPI CLK, %d Hz exceeds 5 MHz\n",
34 			spi->max_speed_hz);
35 		return -EINVAL;
36 	}
37 
38 	regmap = devm_regmap_init_spi(spi, &adxl345_spi_regmap_config);
39 	if (IS_ERR(regmap)) {
40 		dev_err(&spi->dev, "Error initializing spi regmap: %ld\n",
41 			PTR_ERR(regmap));
42 		return PTR_ERR(regmap);
43 	}
44 
45 	return adxl345_core_probe(&spi->dev, regmap, id->driver_data, id->name);
46 }
47 
48 static int adxl345_spi_remove(struct spi_device *spi)
49 {
50 	return adxl345_core_remove(&spi->dev);
51 }
52 
53 static const struct spi_device_id adxl345_spi_id[] = {
54 	{ "adxl345", ADXL345 },
55 	{ "adxl375", ADXL375 },
56 	{ }
57 };
58 
59 MODULE_DEVICE_TABLE(spi, adxl345_spi_id);
60 
61 static const struct of_device_id adxl345_of_match[] = {
62 	{ .compatible = "adi,adxl345" },
63 	{ .compatible = "adi,adxl375" },
64 	{ },
65 };
66 
67 MODULE_DEVICE_TABLE(of, adxl345_of_match);
68 
69 static struct spi_driver adxl345_spi_driver = {
70 	.driver = {
71 		.name	= "adxl345_spi",
72 		.of_match_table = adxl345_of_match,
73 	},
74 	.probe		= adxl345_spi_probe,
75 	.remove		= adxl345_spi_remove,
76 	.id_table	= adxl345_spi_id,
77 };
78 
79 module_spi_driver(adxl345_spi_driver);
80 
81 MODULE_AUTHOR("Eva Rachel Retuya <eraretuya@gmail.com>");
82 MODULE_DESCRIPTION("ADXL345 3-Axis Digital Accelerometer SPI driver");
83 MODULE_LICENSE("GPL v2");
84