LXR linux/drivers/iio/pressure/zpa2326

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Murata ZPA2326 SPI pressure and temperature sensor driver
   4 *
   5 * Copyright (c) 2016 Parrot S.A.
   6 *
   7 * Author: Gregor Boirie <gregor.boirie@parrot.com>
   8 */
   9
  10#include <linux/module.h>
  11#include <linux/regmap.h>
  12#include <linux/spi/spi.h>
  13#include <linux/of_device.h>
  14#include "zpa2326.h"
  15
  16/*
  17 * read_flag_mask:
  18 *   - address bit 7 must be set to request a register read operation
  19 *   - address bit 6 must be set to request register address auto increment
  20 */
  21static const struct regmap_config zpa2326_regmap_spi_config = {
  22        .reg_bits       = 8,
  23        .val_bits       = 8,
  24        .writeable_reg  = zpa2326_isreg_writeable,
  25        .readable_reg   = zpa2326_isreg_readable,
  26        .precious_reg   = zpa2326_isreg_precious,
  27        .max_register   = ZPA2326_TEMP_OUT_H_REG,
  28        .read_flag_mask = BIT(7) | BIT(6),
  29        .cache_type     = REGCACHE_NONE,
  30};
  31
  32static int zpa2326_probe_spi(struct spi_device *spi)
  33{
  34        struct regmap *regmap;
  35        int            err;
  36
  37        regmap = devm_regmap_init_spi(spi, &zpa2326_regmap_spi_config);
  38        if (IS_ERR(regmap)) {
  39                dev_err(&spi->dev, "failed to init registers map");
  40                return PTR_ERR(regmap);
  41        }
  42
  43        /*
  44         * Enforce SPI slave settings to prevent from DT misconfiguration.
  45         *
  46         * Clock is idle high. Sampling happens on trailing edge, i.e., rising
  47         * edge. Maximum bus frequency is 1 MHz. Registers are 8 bits wide.
  48         */
  49        spi->mode = SPI_MODE_3;
  50        spi->max_speed_hz = min(spi->max_speed_hz, 1000000U);
  51        spi->bits_per_word = 8;
  52        err = spi_setup(spi);
  53        if (err < 0)
  54                return err;
  55
  56        return zpa2326_probe(&spi->dev, spi_get_device_id(spi)->name,
  57                             spi->irq, ZPA2326_DEVICE_ID, regmap);
  58}
  59
  60static int zpa2326_remove_spi(struct spi_device *spi)
  61{
  62        zpa2326_remove(&spi->dev);
  63
  64        return 0;
  65}
  66
  67static const struct spi_device_id zpa2326_spi_ids[] = {
  68        { "zpa2326", 0 },
  69        { },
  70};
  71MODULE_DEVICE_TABLE(spi, zpa2326_spi_ids);
  72
  73#if defined(CONFIG_OF)
  74static const struct of_device_id zpa2326_spi_matches[] = {
  75        { .compatible = "murata,zpa2326" },
  76        { }
  77};
  78MODULE_DEVICE_TABLE(of, zpa2326_spi_matches);
  79#endif
  80
  81static struct spi_driver zpa2326_spi_driver = {
  82        .driver = {
  83                .name           = "zpa2326-spi",
  84                .of_match_table = of_match_ptr(zpa2326_spi_matches),
  85                .pm             = ZPA2326_PM_OPS,
  86        },
  87        .probe    = zpa2326_probe_spi,
  88        .remove   = zpa2326_remove_spi,
  89        .id_table = zpa2326_spi_ids,
  90};
  91module_spi_driver(zpa2326_spi_driver);
  92
  93MODULE_AUTHOR("Gregor Boirie <gregor.boirie@parrot.com>");
  94MODULE_DESCRIPTION("SPI driver for Murata ZPA2326 pressure sensor");
  95MODULE_LICENSE("GPL v2");
  96