1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * ADXL345 3-Axis Digital Accelerometer SPI driver
4 *
5 * Copyright (c) 2017 Eva Rachel Retuya <eraretuya@gmail.com>
6 */
7
8 #include <linux/module.h>
9 #include <linux/regmap.h>
10 #include <linux/spi/spi.h>
11
12 #include "adxl345.h"
13
14 #define ADXL345_MAX_SPI_FREQ_HZ 5000000
15 #define ADXL345_MAX_FREQ_NO_FIFO_DELAY 1500000
16
17 static const struct regmap_config adxl345_spi_regmap_config = {
18 .reg_bits = 8,
19 .val_bits = 8,
20 /* Setting bits 7 and 6 enables multiple-byte read */
21 .read_flag_mask = BIT(7) | BIT(6),
22 };
23
adxl345_spi_setup(struct device * dev,struct regmap * regmap)24 static int adxl345_spi_setup(struct device *dev, struct regmap *regmap)
25 {
26 return regmap_write(regmap, ADXL345_REG_DATA_FORMAT, ADXL345_DATA_FORMAT_SPI_3WIRE);
27 }
28
adxl345_spi_probe(struct spi_device * spi)29 static int adxl345_spi_probe(struct spi_device *spi)
30 {
31 struct regmap *regmap;
32 bool needs_delay;
33
34 /* Bail out if max_speed_hz exceeds 5 MHz */
35 if (spi->max_speed_hz > ADXL345_MAX_SPI_FREQ_HZ)
36 return dev_err_probe(&spi->dev, -EINVAL, "SPI CLK, %d Hz exceeds 5 MHz\n",
37 spi->max_speed_hz);
38
39 regmap = devm_regmap_init_spi(spi, &adxl345_spi_regmap_config);
40 if (IS_ERR(regmap))
41 return dev_err_probe(&spi->dev, PTR_ERR(regmap), "Error initializing regmap\n");
42
43 needs_delay = spi->max_speed_hz > ADXL345_MAX_FREQ_NO_FIFO_DELAY;
44 if (spi->mode & SPI_3WIRE)
45 return adxl345_core_probe(&spi->dev, regmap, needs_delay, adxl345_spi_setup);
46 else
47 return adxl345_core_probe(&spi->dev, regmap, needs_delay, NULL);
48 }
49
50 static const struct adxl345_chip_info adxl345_spi_info = {
51 .name = "adxl345",
52 .uscale = ADXL345_USCALE,
53 };
54
55 static const struct adxl345_chip_info adxl375_spi_info = {
56 .name = "adxl375",
57 .uscale = ADXL375_USCALE,
58 };
59
60 static const struct spi_device_id adxl345_spi_id[] = {
61 { "adxl345", (kernel_ulong_t)&adxl345_spi_info },
62 { "adxl375", (kernel_ulong_t)&adxl375_spi_info },
63 { }
64 };
65 MODULE_DEVICE_TABLE(spi, adxl345_spi_id);
66
67 static const struct of_device_id adxl345_of_match[] = {
68 { .compatible = "adi,adxl345", .data = &adxl345_spi_info },
69 { .compatible = "adi,adxl375", .data = &adxl375_spi_info },
70 { }
71 };
72 MODULE_DEVICE_TABLE(of, adxl345_of_match);
73
74 static const struct acpi_device_id adxl345_acpi_match[] = {
75 { "ADS0345", (kernel_ulong_t)&adxl345_spi_info },
76 { }
77 };
78 MODULE_DEVICE_TABLE(acpi, adxl345_acpi_match);
79
80 static struct spi_driver adxl345_spi_driver = {
81 .driver = {
82 .name = "adxl345_spi",
83 .of_match_table = adxl345_of_match,
84 .acpi_match_table = adxl345_acpi_match,
85 },
86 .probe = adxl345_spi_probe,
87 .id_table = adxl345_spi_id,
88 };
89 module_spi_driver(adxl345_spi_driver);
90
91 MODULE_AUTHOR("Eva Rachel Retuya <eraretuya@gmail.com>");
92 MODULE_DESCRIPTION("ADXL345 3-Axis Digital Accelerometer SPI driver");
93 MODULE_LICENSE("GPL v2");
94 MODULE_IMPORT_NS("IIO_ADXL345");
95