1/*
 2 * soc-io.c  --  ASoC register I/O helpers
 3 *
 4 * Copyright 2009-2011 Wolfson Microelectronics PLC.
 5 *
 6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
 7 *
 8 *  This program is free software; you can redistribute  it and/or modify it
 9 *  under  the terms of  the GNU General  Public License as published by the
10 *  Free Software Foundation;  either version 2 of the  License, or (at your
11 *  option) any later version.
12 */
13
14#include <linux/i2c.h>
15#include <linux/spi/spi.h>
16#include <linux/regmap.h>
17#include <linux/export.h>
18#include <sound/soc.h>
19
20#include <trace/events/asoc.h>
21
22#ifdef CONFIG_REGMAP
23static int hw_write(struct snd_soc_codec *codec, unsigned int reg,
24		    unsigned int value)
25{
26	return regmap_write(codec->control_data, reg, value);
27}
28
29static unsigned int hw_read(struct snd_soc_codec *codec, unsigned int reg)
30{
31	int ret;
32	unsigned int val;
33
34	ret = regmap_read(codec->control_data, reg, &val);
35	if (ret == 0)
36		return val;
37	else
38		return -1;
39}
40
41/**
42 * snd_soc_codec_set_cache_io: Set up standard I/O functions.
43 *
44 * @codec: CODEC to configure.
45 * @map: Register map to write to
46 *
47 * Register formats are frequently shared between many I2C and SPI
48 * devices.  In order to promote code reuse the ASoC core provides
49 * some standard implementations of CODEC read and write operations
50 * which can be set up using this function.
51 *
52 * The caller is responsible for allocating and initialising the
53 * actual cache.
54 *
55 * Note that at present this code cannot be used by CODECs with
56 * volatile registers.
57 */
58int snd_soc_codec_set_cache_io(struct snd_soc_codec *codec,
59			       struct regmap *regmap)
60{
61	int ret;
62
63	/* Device has made its own regmap arrangements */
64	if (!regmap)
65		codec->control_data = dev_get_regmap(codec->dev, NULL);
66	else
67		codec->control_data = regmap;
68
69	if (IS_ERR(codec->control_data))
70		return PTR_ERR(codec->control_data);
71
72	codec->write = hw_write;
73	codec->read = hw_read;
74
75	ret = regmap_get_val_bytes(codec->control_data);
76	/* Errors are legitimate for non-integer byte
77	 * multiples */
78	if (ret > 0)
79		codec->val_bytes = ret;
80
81	codec->using_regmap = true;
82
83	return 0;
84}
85EXPORT_SYMBOL_GPL(snd_soc_codec_set_cache_io);
86#else
87int snd_soc_codec_set_cache_io(struct snd_soc_codec *codec,
88			       struct regmap *regmap)
89{
90	return -ENOTSUPP;
91}
92EXPORT_SYMBOL_GPL(snd_soc_codec_set_cache_io);
93#endif