LXR linux/sound/soc/codecs/adau1977-spi.c

   1/*
   2 * ADAU1977/ADAU1978/ADAU1979 driver
   3 *
   4 * Copyright 2014 Analog Devices Inc.
   5 *  Author: Lars-Peter Clausen <lars@metafoo.de>
   6 *
   7 * Licensed under the GPL-2.
   8 */
   9
  10#include <linux/mod_devicetable.h>
  11#include <linux/module.h>
  12#include <linux/regmap.h>
  13#include <linux/spi/spi.h>
  14#include <sound/soc.h>
  15
  16#include "adau1977.h"
  17
  18static void adau1977_spi_switch_mode(struct device *dev)
  19{
  20        struct spi_device *spi = to_spi_device(dev);
  21
  22        /*
  23         * To get the device into SPI mode CLATCH has to be pulled low three
  24         * times.  Do this by issuing three dummy reads.
  25         */
  26        spi_w8r8(spi, 0x00);
  27        spi_w8r8(spi, 0x00);
  28        spi_w8r8(spi, 0x00);
  29}
  30
  31static int adau1977_spi_probe(struct spi_device *spi)
  32{
  33        const struct spi_device_id *id = spi_get_device_id(spi);
  34        struct regmap_config config;
  35
  36        if (!id)
  37                return -EINVAL;
  38
  39        config = adau1977_regmap_config;
  40        config.val_bits = 8;
  41        config.reg_bits = 16;
  42        config.read_flag_mask = 0x1;
  43
  44        return adau1977_probe(&spi->dev,
  45                devm_regmap_init_spi(spi, &config),
  46                id->driver_data, adau1977_spi_switch_mode);
  47}
  48
  49static const struct spi_device_id adau1977_spi_ids[] = {
  50        { "adau1977", ADAU1977 },
  51        { "adau1978", ADAU1978 },
  52        { "adau1979", ADAU1978 },
  53        { }
  54};
  55MODULE_DEVICE_TABLE(spi, adau1977_spi_ids);
  56
  57static struct spi_driver adau1977_spi_driver = {
  58        .driver = {
  59                .name = "adau1977",
  60        },
  61        .probe = adau1977_spi_probe,
  62        .id_table = adau1977_spi_ids,
  63};
  64module_spi_driver(adau1977_spi_driver);
  65
  66MODULE_DESCRIPTION("ASoC ADAU1977/ADAU1978/ADAU1979 driver");
  67MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
  68MODULE_LICENSE("GPL");
  69