drivers/iio/accel/adxl345_spi.c

   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->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", 0 },
  55         { }
  56 };
  57
  58 MODULE_DEVICE_TABLE(spi, adxl345_spi_id);
  59
  60 static const struct of_device_id adxl345_of_match[] = {
  61         { .compatible = "adi,adxl345" },
  62         { },
  63 };
  64
  65 MODULE_DEVICE_TABLE(of, adxl345_of_match);
  66
  67 static struct spi_driver adxl345_spi_driver = {
  68         .driver = {
  69                 .name   = "adxl345_spi",
  70                 .of_match_table = adxl345_of_match,
  71         },
  72         .probe          = adxl345_spi_probe,
  73         .remove         = adxl345_spi_remove,
  74         .id_table       = adxl345_spi_id,
  75 };
  76
  77 module_spi_driver(adxl345_spi_driver);
  78
  79 MODULE_AUTHOR("Eva Rachel Retuya <eraretuya@gmail.com>");
  80 MODULE_DESCRIPTION("ADXL345 3-Axis Digital Accelerometer SPI driver");
  81 MODULE_LICENSE("GPL v2");