1 files changed, 340 insertions, 0 deletions
diff --git a/sound/soc/soc-cache.c b/sound/soc/soc-cache.c
new file mode 100644
index 00000000..9d56f021
--- /dev/null
+++ b/sound/soc/soc-cache.c
@@ -0,0 +1,340 @@
+/*
+ * 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 <linux/i2c.h>
+#include <linux/spi/spi.h>
+#include <sound/soc.h>
+#include <linux/bitmap.h>
+#include <linux/rbtree.h>
+#include <linux/export.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:
+		BUG();
+	}
+	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:
+		BUG();
+	}
+	/* unreachable */
+	return -1;
+}
+
+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->reg_def_copy)
+			if (snd_soc_get_cache_val(codec->reg_def_copy,
+						  i, codec_drv->reg_word_size) == val)
+				continue;
+
+		WARN_ON(!snd_soc_codec_writable_register(codec, i));
+
+		ret = snd_soc_write(codec, i, val);
+		if (ret)
+			return ret;
+		dev_dbg(codec->dev, "Synced register %#x, value = %#x\n",
+			i, val);
+	}
+	return 0;
+}
+
+static int snd_soc_flat_cache_write(struct snd_soc_codec *codec,
+				    unsigned int reg, unsigned int value)
+{
+	snd_soc_set_cache_val(codec->reg_cache, reg, value,
+			      codec->driver->reg_word_size);
+	return 0;
+}
+
+static int snd_soc_flat_cache_read(struct snd_soc_codec *codec,
+				   unsigned int reg, unsigned int *value)
+{
+	*value = snd_soc_get_cache_val(codec->reg_cache, reg,
+				       codec->driver->reg_word_size);
+	return 0;
+}
+
+static int snd_soc_flat_cache_exit(struct snd_soc_codec *codec)
+{
+	if (!codec->reg_cache)
+		return 0;
+	kfree(codec->reg_cache);
+	codec->reg_cache = NULL;
+	return 0;
+}
+
+static int snd_soc_flat_cache_init(struct snd_soc_codec *codec)
+{
+	if (codec->reg_def_copy)
+		codec->reg_cache = kmemdup(codec->reg_def_copy,
+					   codec->reg_size, GFP_KERNEL);
+	else
+		codec->reg_cache = kzalloc(codec->reg_size, GFP_KERNEL);
+	if (!codec->reg_cache)
+		return -ENOMEM;
+
+	return 0;
+}
+
+/* an array of all supported compression types */
+static const struct snd_soc_cache_ops cache_types[] = {
+	/* Flat *must* be the first entry for fallback */
+	{
+		.id = SND_SOC_FLAT_COMPRESSION,
+		.name = "flat",
+		.init = snd_soc_flat_cache_init,
+		.exit = snd_soc_flat_cache_exit,
+		.read = snd_soc_flat_cache_read,
+		.write = snd_soc_flat_cache_write,
+		.sync = snd_soc_flat_cache_sync
+	},
+};
+
+int snd_soc_cache_init(struct snd_soc_codec *codec)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(cache_types); ++i)
+		if (cache_types[i].id == codec->compress_type)
+			break;
+
+	/* Fall back to flat compression */
+	if (i == ARRAY_SIZE(cache_types)) {
+		dev_warn(codec->dev, "Could not match compress type: %d\n",
+			 codec->compress_type);
+		i = 0;
+	}
+
+	mutex_init(&codec->cache_rw_mutex);
+	codec->cache_ops = &cache_types[i];
+
+	if (codec->cache_ops->init) {
+		if (codec->cache_ops->name)
+			dev_dbg(codec->dev, "Initializing %s cache for %s codec\n",
+				codec->cache_ops->name, codec->name);
+		return codec->cache_ops->init(codec);
+	}
+	return -ENOSYS;
+}
+
+/*
+ * NOTE: keep in mind that this function might be called
+ * multiple times.
+ */
+int snd_soc_cache_exit(struct snd_soc_codec *codec)
+{
+	if (codec->cache_ops && codec->cache_ops->exit) {
+		if (codec->cache_ops->name)
+			dev_dbg(codec->dev, "Destroying %s cache for %s codec\n",
+				codec->cache_ops->name, codec->name);
+		return codec->cache_ops->exit(codec);
+	}
+	return -ENOSYS;
+}
+
+/**
+ * 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)
+{
+	int ret;
+
+	mutex_lock(&codec->cache_rw_mutex);
+
+	if (value && codec->cache_ops && codec->cache_ops->read) {
+		ret = codec->cache_ops->read(codec, reg, value);
+		mutex_unlock(&codec->cache_rw_mutex);
+		return ret;
+	}
+
+	mutex_unlock(&codec->cache_rw_mutex);
+	return -ENOSYS;
+}
+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)
+{
+	int ret;
+
+	mutex_lock(&codec->cache_rw_mutex);
+
+	if (codec->cache_ops && codec->cache_ops->write) {
+		ret = codec->cache_ops->write(codec, reg, value);
+		mutex_unlock(&codec->cache_rw_mutex);
+		return ret;
+	}
+
+	mutex_unlock(&codec->cache_rw_mutex);
+	return -ENOSYS;
+}
+EXPORT_SYMBOL_GPL(snd_soc_cache_write);
+
+/**
+ * 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)
+{
+	int ret;
+	const char *name;
+
+	if (!codec->cache_sync) {
+		return 0;
+	}
+
+	if (!codec->cache_ops || !codec->cache_ops->sync)
+		return -ENOSYS;
+
+	if (codec->cache_ops->name)
+		name = codec->cache_ops->name;
+	else
+		name = "unknown";
+
+	if (codec->cache_ops->name)
+		dev_dbg(codec->dev, "Syncing %s cache for %s codec\n",
+			codec->cache_ops->name, codec->name);
+	trace_snd_soc_cache_sync(codec, name, "start");
+	ret = codec->cache_ops->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);
+
+static int snd_soc_get_reg_access_index(struct snd_soc_codec *codec,
+					unsigned int reg)
+{
+	const struct snd_soc_codec_driver *codec_drv;
+	unsigned int min, max, index;
+
+	codec_drv = codec->driver;
+	min = 0;
+	max = codec_drv->reg_access_size - 1;
+	do {
+		index = (min + max) / 2;
+		if (codec_drv->reg_access_default[index].reg == reg)
+			return index;
+		if (codec_drv->reg_access_default[index].reg < reg)
+			min = index + 1;
+		else
+			max = index;
+	} while (min <= max);
+	return -1;
+}
+
+int snd_soc_default_volatile_register(struct snd_soc_codec *codec,
+				      unsigned int reg)
+{
+	int index;
+
+	if (reg >= codec->driver->reg_cache_size)
+		return 1;
+	index = snd_soc_get_reg_access_index(codec, reg);
+	if (index < 0)
+		return 0;
+	return codec->driver->reg_access_default[index].vol;
+}
+EXPORT_SYMBOL_GPL(snd_soc_default_volatile_register);
+
+int snd_soc_default_readable_register(struct snd_soc_codec *codec,
+				      unsigned int reg)
+{
+	int index;
+
+	if (reg >= codec->driver->reg_cache_size)
+		return 1;
+	index = snd_soc_get_reg_access_index(codec, reg);
+	if (index < 0)
+		return 0;
+	return codec->driver->reg_access_default[index].read;
+}
+EXPORT_SYMBOL_GPL(snd_soc_default_readable_register);
+
+int snd_soc_default_writable_register(struct snd_soc_codec *codec,
+				      unsigned int reg)
+{
+	int index;
+
+	if (reg >= codec->driver->reg_cache_size)
+		return 1;
+	index = snd_soc_get_reg_access_index(codec, reg);
+	if (index < 0)
+		return 0;
+	return codec->driver->reg_access_default[index].write;
+}
+EXPORT_SYMBOL_GPL(snd_soc_default_writable_register);