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 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 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