2 * soc-cache.c -- ASoC register cache helpers
4 * Copyright 2009 Wolfson Microelectronics PLC.
6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
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.
14 #include <sound/soc.h>
15 #include <linux/export.h>
16 #include <linux/slab.h>
18 #include <trace/events/asoc.h>
20 static bool snd_soc_set_cache_val(void *base, unsigned int idx,
21 unsigned int val, unsigned int word_size)
26 if (cache[idx] == val)
33 if (cache[idx] == val)
44 static unsigned int snd_soc_get_cache_val(const void *base, unsigned int idx,
45 unsigned int word_size)
52 const u8 *cache = base;
56 const u16 *cache = base;
66 int snd_soc_cache_init(struct snd_soc_codec *codec)
68 const struct snd_soc_codec_driver *codec_drv = codec->driver;
71 reg_size = codec_drv->reg_cache_size * codec_drv->reg_word_size;
73 mutex_init(&codec->cache_rw_mutex);
75 dev_dbg(codec->dev, "ASoC: Initializing cache for %s codec\n",
78 if (codec_drv->reg_cache_default)
79 codec->reg_cache = kmemdup(codec_drv->reg_cache_default,
80 reg_size, GFP_KERNEL);
82 codec->reg_cache = kzalloc(reg_size, GFP_KERNEL);
83 if (!codec->reg_cache)
90 * NOTE: keep in mind that this function might be called
93 int snd_soc_cache_exit(struct snd_soc_codec *codec)
95 dev_dbg(codec->dev, "ASoC: Destroying cache for %s codec\n",
97 if (!codec->reg_cache)
99 kfree(codec->reg_cache);
100 codec->reg_cache = NULL;
105 * snd_soc_cache_read: Fetch the value of a given register from the cache.
107 * @codec: CODEC to configure.
108 * @reg: The register index.
109 * @value: The value to be returned.
111 int snd_soc_cache_read(struct snd_soc_codec *codec,
112 unsigned int reg, unsigned int *value)
117 mutex_lock(&codec->cache_rw_mutex);
118 *value = snd_soc_get_cache_val(codec->reg_cache, reg,
119 codec->driver->reg_word_size);
120 mutex_unlock(&codec->cache_rw_mutex);
124 EXPORT_SYMBOL_GPL(snd_soc_cache_read);
127 * snd_soc_cache_write: Set the value of a given register in the cache.
129 * @codec: CODEC to configure.
130 * @reg: The register index.
131 * @value: The new register value.
133 int snd_soc_cache_write(struct snd_soc_codec *codec,
134 unsigned int reg, unsigned int value)
136 mutex_lock(&codec->cache_rw_mutex);
137 snd_soc_set_cache_val(codec->reg_cache, reg, value,
138 codec->driver->reg_word_size);
139 mutex_unlock(&codec->cache_rw_mutex);
143 EXPORT_SYMBOL_GPL(snd_soc_cache_write);
145 static int snd_soc_flat_cache_sync(struct snd_soc_codec *codec)
149 const struct snd_soc_codec_driver *codec_drv;
152 codec_drv = codec->driver;
153 for (i = 0; i < codec_drv->reg_cache_size; ++i) {
154 ret = snd_soc_cache_read(codec, i, &val);
157 if (codec_drv->reg_cache_default)
158 if (snd_soc_get_cache_val(codec_drv->reg_cache_default,
159 i, codec_drv->reg_word_size) == val)
162 WARN_ON(!snd_soc_codec_writable_register(codec, i));
164 ret = snd_soc_write(codec, i, val);
167 dev_dbg(codec->dev, "ASoC: Synced register %#x, value = %#x\n",
174 * snd_soc_cache_sync: Sync the register cache with the hardware.
176 * @codec: CODEC to configure.
178 * Any registers that should not be synced should be marked as
179 * volatile. In general drivers can choose not to use the provided
180 * syncing functionality if they so require.
182 int snd_soc_cache_sync(struct snd_soc_codec *codec)
184 const char *name = "flat";
187 if (!codec->cache_sync)
190 dev_dbg(codec->dev, "ASoC: Syncing cache for %s codec\n",
192 trace_snd_soc_cache_sync(codec, name, "start");
193 ret = snd_soc_flat_cache_sync(codec);
195 codec->cache_sync = 0;
196 trace_snd_soc_cache_sync(codec, name, "end");
199 EXPORT_SYMBOL_GPL(snd_soc_cache_sync);