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 .volatile_reg = adxl345_is_volatile_reg,
23 .cache_type = REGCACHE_MAPLE,
24 };
25
adxl345_spi_setup(struct device * dev,struct regmap * regmap)26 static int adxl345_spi_setup(struct device *dev, struct regmap *regmap)
27 {
28 return regmap_write(regmap, ADXL345_REG_DATA_FORMAT, ADXL345_DATA_FORMAT_SPI_3WIRE);
29 }
30
adxl345_spi_probe(struct spi_device * spi)31 static int adxl345_spi_probe(struct spi_device *spi)
32 {
33 struct regmap *regmap;
34 bool needs_delay;
35
36 /* Bail out if max_speed_hz exceeds 5 MHz */
37 if (spi->max_speed_hz > ADXL345_MAX_SPI_FREQ_HZ)
38 return dev_err_probe(&spi->dev, -EINVAL, "SPI CLK, %d Hz exceeds 5 MHz\n",
39 spi->max_speed_hz);
40
41 regmap = devm_regmap_init_spi(spi, &adxl345_spi_regmap_config);
42 if (IS_ERR(regmap))
43 return dev_err_probe(&spi->dev, PTR_ERR(regmap), "Error initializing regmap\n");
44
45 needs_delay = spi->max_speed_hz > ADXL345_MAX_FREQ_NO_FIFO_DELAY;
46 if (spi->mode & SPI_3WIRE)
47 return adxl345_core_probe(&spi->dev, regmap, needs_delay, adxl345_spi_setup);
48 else
49 return adxl345_core_probe(&spi->dev, regmap, needs_delay, NULL);
50 }
51
52 static const struct adxl345_chip_info adxl345_spi_info = {
53 .name = "adxl345",
54 .uscale = ADXL345_USCALE,
55 };
56
57 static const struct adxl345_chip_info adxl375_spi_info = {
58 .name = "adxl375",
59 .uscale = ADXL375_USCALE,
60 };
61
62 static const struct spi_device_id adxl345_spi_id[] = {
63 { "adxl345", (kernel_ulong_t)&adxl345_spi_info },
64 { "adxl375", (kernel_ulong_t)&adxl375_spi_info },
65 { }
66 };
67 MODULE_DEVICE_TABLE(spi, adxl345_spi_id);
68
69 static const struct of_device_id adxl345_of_match[] = {
70 { .compatible = "adi,adxl345", .data = &adxl345_spi_info },
71 { .compatible = "adi,adxl375", .data = &adxl375_spi_info },
72 { }
73 };
74 MODULE_DEVICE_TABLE(of, adxl345_of_match);
75
76 static const struct acpi_device_id adxl345_acpi_match[] = {
77 { "ADS0345", (kernel_ulong_t)&adxl345_spi_info },
78 { }
79 };
80 MODULE_DEVICE_TABLE(acpi, adxl345_acpi_match);
81
82 static struct spi_driver adxl345_spi_driver = {
83 .driver = {
84 .name = "adxl345_spi",
85 .of_match_table = adxl345_of_match,
86 .acpi_match_table = adxl345_acpi_match,
87 },
88 .probe = adxl345_spi_probe,
89 .id_table = adxl345_spi_id,
90 };
91 module_spi_driver(adxl345_spi_driver);
92
93 MODULE_AUTHOR("Eva Rachel Retuya <eraretuya@gmail.com>");
94 MODULE_DESCRIPTION("ADXL345 3-Axis Digital Accelerometer SPI driver");
95 MODULE_LICENSE("GPL v2");
96 MODULE_IMPORT_NS("IIO_ADXL345");
97