summaryrefslogtreecommitdiffstats
path: root/sound/soc/soc-cache.c
blob: 00e70b6c7da2ea78e622ca3d0ce36360f3ede593 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
/*
 * soc-cache.c  --  ASoC register cache helpers
 *
 * Copyright 2009 Wolfson Microelectronics PLC.
 *
 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
 *
 *  This program is free software; you can redistribute  it and/or modify it
 *  under  the terms of  the GNU General  Public License as published by the
 *  Free Software Foundation;  either version 2 of the  License, or (at your
 *  option) any later version.
 */

#include <sound/soc.h>
#include <linux/export.h>
#include <linux/slab.h>

#include <trace/events/asoc.h>

static bool snd_soc_set_cache_val(void *base, unsigned int idx,
				  unsigned int val, unsigned int word_size)
{
	switch (word_size) {
	case 1: {
		u8 *cache = base;
		if (cache[idx] == val)
			return true;
		cache[idx] = val;
		break;
	}
	case 2: {
		u16 *cache = base;
		if (cache[idx] == val)
			return true;
		cache[idx] = val;
		break;
	}
	default:
		WARN(1, "Invalid word_size %d\n", word_size);
		break;
	}
	return false;
}

static unsigned int snd_soc_get_cache_val(const void *base, unsigned int idx,
		unsigned int word_size)
{
	if (!base)
		return -1;

	switch (word_size) {
	case 1: {
		const u8 *cache = base;
		return cache[idx];
	}
	case 2: {
		const u16 *cache = base;
		return cache[idx];
	}
	default:
		WARN(1, "Invalid word_size %d\n", word_size);
		break;
	}
	/* unreachable */
	return -1;
}

int snd_soc_cache_init(struct snd_soc_codec *codec)
{
	const struct snd_soc_codec_driver *codec_drv = codec->driver;
	size_t reg_size;

	reg_size = codec_drv->reg_cache_size * codec_drv->reg_word_size;

	if (!reg_size)
		return 0;

	mutex_init(&codec->cache_rw_mutex);

	dev_dbg(codec->dev, "ASoC: Initializing cache for %s codec\n",
				codec->name);

	if (codec_drv->reg_cache_default)
		codec->reg_cache = kmemdup(codec_drv->reg_cache_default,
					   reg_size, GFP_KERNEL);
	else
		codec->reg_cache = kzalloc(reg_size, GFP_KERNEL);
	if (!codec->reg_cache)
		return -ENOMEM;

	return 0;
}

/*
 * NOTE: keep in mind that this function might be called
 * multiple times.
 */
int snd_soc_cache_exit(struct snd_soc_codec *codec)
{
	dev_dbg(codec->dev, "ASoC: Destroying cache for %s codec\n",
			codec->name);

	kfree(codec->reg_cache);
	codec->reg_cache = NULL;
	return 0;
}

/**
 * snd_soc_cache_read: Fetch the value of a given register from the cache.
 *
 * @codec: CODEC to configure.
 * @reg: The register index.
 * @value: The value to be returned.
 */
int snd_soc_cache_read(struct snd_soc_codec *codec,
		       unsigned int reg, unsigned int *value)
{
	if (!value)
		return -EINVAL;

	mutex_lock(&codec->cache_rw_mutex);
	if (!ZERO_OR_NULL_PTR(codec->reg_cache))
		*value = snd_soc_get_cache_val(codec->reg_cache, reg,
					       codec->driver->reg_word_size);
	mutex_unlock(&codec->cache_rw_mutex);

	return 0;
}
EXPORT_SYMBOL_GPL(snd_soc_cache_read);

/**
 * snd_soc_cache_write: Set the value of a given register in the cache.
 *
 * @codec: CODEC to configure.
 * @reg: The register index.
 * @value: The new register value.
 */
int snd_soc_cache_write(struct snd_soc_codec *codec,
			unsigned int reg, unsigned int value)
{
	mutex_lock(&codec->cache_rw_mutex);
	if (!ZERO_OR_NULL_PTR(codec->reg_cache))
		snd_soc_set_cache_val(codec->reg_cache, reg, value,
				      codec->driver->reg_word_size);
	mutex_unlock(&codec->cache_rw_mutex);

	return 0;
}
EXPORT_SYMBOL_GPL(snd_soc_cache_write);

static int snd_soc_flat_cache_sync(struct snd_soc_codec *codec)
{
	int i;
	int ret;
	const struct snd_soc_codec_driver *codec_drv;
	unsigned int val;

	codec_drv = codec->driver;
	for (i = 0; i < codec_drv->reg_cache_size; ++i) {
		ret = snd_soc_cache_read(codec, i, &val);
		if (ret)
			return ret;
		if (codec_drv->reg_cache_default)
			if (snd_soc_get_cache_val(codec_drv->reg_cache_default,
						  i, codec_drv->reg_word_size) == val)
				continue;

		ret = snd_soc_write(codec, i, val);
		if (ret)
			return ret;
		dev_dbg(codec->dev, "ASoC: Synced register %#x, value = %#x\n",
			i, val);
	}
	return 0;
}

/**
 * snd_soc_cache_sync: Sync the register cache with the hardware.
 *
 * @codec: CODEC to configure.
 *
 * Any registers that should not be synced should be marked as
 * volatile.  In general drivers can choose not to use the provided
 * syncing functionality if they so require.
 */
int snd_soc_cache_sync(struct snd_soc_codec *codec)
{
	const char *name = "flat";
	int ret;

	if (!codec->cache_sync)
		return 0;

	dev_dbg(codec->dev, "ASoC: Syncing cache for %s codec\n",
		codec->name);
	trace_snd_soc_cache_sync(codec, name, "start");
	ret = snd_soc_flat_cache_sync(codec);
	if (!ret)
		codec->cache_sync = 0;
	trace_snd_soc_cache_sync(codec, name, "end");
	return ret;
}
EXPORT_SYMBOL_GPL(snd_soc_cache_sync);
OpenPOWER on IntegriCloud