sound/soc/codecs/adau1781-spi.c

   1 /*
   2  * Driver for ADAU1381/ADAU1781 CODEC
   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 "adau1781.h"
  17
  18 static void adau1781_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
  31 static int adau1781_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 = adau1781_regmap_config;
  40         config.val_bits = 8;
  41         config.reg_bits = 24;
  42         config.read_flag_mask = 0x1;
  43
  44         return adau1781_probe(&spi->dev,
  45                 devm_regmap_init_spi(spi, &config),
  46                 id->driver_data, adau1781_spi_switch_mode);
  47 }
  48
  49 static int adau1781_spi_remove(struct spi_device *spi)
  50 {
  51         snd_soc_unregister_codec(&spi->dev);
  52         return 0;
  53 }
  54
  55 static const struct spi_device_id adau1781_spi_id[] = {
  56         { "adau1381", ADAU1381 },
  57         { "adau1781", ADAU1781 },
  58         { }
  59 };
  60 MODULE_DEVICE_TABLE(spi, adau1781_spi_id);
  61
  62 static struct spi_driver adau1781_spi_driver = {
  63         .driver = {
  64                 .name = "adau1781",
  65                 .owner = THIS_MODULE,
  66         },
  67         .probe = adau1781_spi_probe,
  68         .remove = adau1781_spi_remove,
  69         .id_table = adau1781_spi_id,
  70 };
  71 module_spi_driver(adau1781_spi_driver);
  72
  73 MODULE_DESCRIPTION("ASoC ADAU1381/ADAU1781 CODEC SPI driver");
  74 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
  75 MODULE_LICENSE("GPL");