drivers/iio/accel/adxl345_spi.c

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