CHROMIUM: ASoC: Import entire upstream ASoC tree

sound/soc/soc-cache.c

Index: sound/soc/soc-cache.c
diff --git a/sound/soc/soc-cache.c b/sound/soc/soc-cache.c
index d214f02cbb65a46314a121948525cb2b005734e1..5d76da43b14c1ddfa0e53c0c60a358263bb7d488 100644
--- a/sound/soc/soc-cache.c
+++ b/sound/soc/soc-cache.c
@@ -14,27 +14,37 @@
 #include <linux/i2c.h>
 #include <linux/spi/spi.h>
 #include <sound/soc.h>
+#include <linux/lzo.h>
+#include <linux/bitmap.h>
+#include <linux/rbtree.h>
+
+#include <trace/events/asoc.h>
 
 static unsigned int snd_soc_4_12_read(struct snd_soc_codec *codec,
 				     unsigned int reg)
 {
-	u16 *cache = codec->reg_cache;
+	int ret;
+	unsigned int val;
 
 	if (reg >= codec->driver->reg_cache_size ||
-		snd_soc_codec_volatile_register(codec, reg)) {
+		snd_soc_codec_volatile_register(codec, reg) ||
+		codec->cache_bypass) {
 			if (codec->cache_only)
 				return -1;
 
+			BUG_ON(!codec->hw_read);
 			return codec->hw_read(codec, reg);
 	}
 
-	return cache[reg];
+	ret = snd_soc_cache_read(codec, reg, &val);
+	if (ret < 0)
+		return -1;
+	return val;
 }
 
 static int snd_soc_4_12_write(struct snd_soc_codec *codec, unsigned int reg,
 			     unsigned int value)
 {
-	u16 *cache = codec->reg_cache;
 	u8 data[2];
 	int ret;
 
@@ -42,16 +52,18 @@ static int snd_soc_4_12_write(struct snd_soc_codec *codec, unsigned int reg,
 	data[1] = value & 0x00ff;
 
 	if (!snd_soc_codec_volatile_register(codec, reg) &&
-		reg < codec->driver->reg_cache_size)
-			cache[reg] = value;
+		reg < codec->driver->reg_cache_size &&
+		!codec->cache_bypass) {
+		ret = snd_soc_cache_write(codec, reg, value);
+		if (ret < 0)
+			return -1;
+	}
 
 	if (codec->cache_only) {
 		codec->cache_sync = 1;
 		return 0;
 	}
 
-	dev_dbg(codec->dev, "0x%x = 0x%x\n", reg, value);
-
 	ret = codec->hw_write(codec->control_data, data, 2);
 	if (ret == 2)
 		return 0;
@@ -77,7 +89,7 @@ static int snd_soc_4_12_spi_write(void *control_data, const char *data,
 	msg[1] = data[0];
 
 	spi_message_init(&m);
-	memset(&t, 0, (sizeof t));
+	memset(&t, 0, sizeof t);
 
 	t.tx_buf = &msg[0];
 	t.len = len;
@@ -94,23 +106,28 @@ static int snd_soc_4_12_spi_write(void *control_data, const char *data,
 static unsigned int snd_soc_7_9_read(struct snd_soc_codec *codec,
 				     unsigned int reg)
 {
-	u16 *cache = codec->reg_cache;
+	int ret;
+	unsigned int val;
 
 	if (reg >= codec->driver->reg_cache_size ||
-		snd_soc_codec_volatile_register(codec, reg)) {
+		snd_soc_codec_volatile_register(codec, reg) ||
+		codec->cache_bypass) {
 			if (codec->cache_only)
 				return -1;
 
+			BUG_ON(!codec->hw_read);
 			return codec->hw_read(codec, reg);
 	}
 
-	return cache[reg];
+	ret = snd_soc_cache_read(codec, reg, &val);
+	if (ret < 0)
+		return -1;
+	return val;
 }
 
 static int snd_soc_7_9_write(struct snd_soc_codec *codec, unsigned int reg,
 			     unsigned int value)
 {
-	u16 *cache = codec->reg_cache;
 	u8 data[2];
 	int ret;
 
@@ -118,16 +135,18 @@ static int snd_soc_7_9_write(struct snd_soc_codec *codec, unsigned int reg,
 	data[1] = value & 0x00ff;
 
 	if (!snd_soc_codec_volatile_register(codec, reg) &&
-		reg < codec->driver->reg_cache_size)
-			cache[reg] = value;
+		reg < codec->driver->reg_cache_size &&
+		!codec->cache_bypass) {
+		ret = snd_soc_cache_write(codec, reg, value);
+		if (ret < 0)
+			return -1;
+	}
 
 	if (codec->cache_only) {
 		codec->cache_sync = 1;
 		return 0;
 	}
 
-	dev_dbg(codec->dev, "0x%x = 0x%x\n", reg, value);
-
 	ret = codec->hw_write(codec->control_data, data, 2);
 	if (ret == 2)
 		return 0;
@@ -153,7 +172,7 @@ static int snd_soc_7_9_spi_write(void *control_data, const char *data,
 	msg[1] = data[1];
 
 	spi_message_init(&m);
-	memset(&t, 0, (sizeof t));
+	memset(&t, 0, sizeof t);
 
 	t.tx_buf = &msg[0];
 	t.len = len;
@@ -170,24 +189,26 @@ static int snd_soc_7_9_spi_write(void *control_data, const char *data,
 static int snd_soc_8_8_write(struct snd_soc_codec *codec, unsigned int reg,
 			     unsigned int value)
 {
-	u8 *cache = codec->reg_cache;
 	u8 data[2];
+	int ret;
 
 	reg &= 0xff;
 	data[0] = reg;
 	data[1] = value & 0xff;
 
 	if (!snd_soc_codec_volatile_register(codec, reg) &&
-		reg < codec->driver->reg_cache_size)
-			cache[reg] = value;
+		reg < codec->driver->reg_cache_size &&
+		!codec->cache_bypass) {
+		ret = snd_soc_cache_write(codec, reg, value);
+		if (ret < 0)
+			return -1;
+	}
 
 	if (codec->cache_only) {
 		codec->cache_sync = 1;
 		return 0;
 	}
 
-	dev_dbg(codec->dev, "0x%x = 0x%x\n", reg, value);
-
 	if (codec->hw_write(codec->control_data, data, 2) == 2)
 		return 0;
 	else
@@ -197,18 +218,24 @@ static int snd_soc_8_8_write(struct snd_soc_codec *codec, unsigned int reg,
 static unsigned int snd_soc_8_8_read(struct snd_soc_codec *codec,
 				     unsigned int reg)
 {
-	u8 *cache = codec->reg_cache;
+	int ret;
+	unsigned int val;
 
 	reg &= 0xff;
 	if (reg >= codec->driver->reg_cache_size ||
-		snd_soc_codec_volatile_register(codec, reg)) {
+		snd_soc_codec_volatile_register(codec, reg) ||
+		codec->cache_bypass) {
 			if (codec->cache_only)
 				return -1;
 
+			BUG_ON(!codec->hw_read);
 			return codec->hw_read(codec, reg);
 	}
 
-	return cache[reg];
+	ret = snd_soc_cache_read(codec, reg, &val);
+	if (ret < 0)
+		return -1;
+	return val;
 }
 
 #if defined(CONFIG_SPI_MASTER)
@@ -227,7 +254,7 @@ static int snd_soc_8_8_spi_write(void *control_data, const char *data,
 	msg[1] = data[1];
 
 	spi_message_init(&m);
-	memset(&t, 0, (sizeof t));
+	memset(&t, 0, sizeof t);
 
 	t.tx_buf = &msg[0];
 	t.len = len;
@@ -244,24 +271,26 @@ static int snd_soc_8_8_spi_write(void *control_data, const char *data,
 static int snd_soc_8_16_write(struct snd_soc_codec *codec, unsigned int reg,
 			      unsigned int value)
 {
-	u16 *reg_cache = codec->reg_cache;
 	u8 data[3];
+	int ret;
 
 	data[0] = reg;
 	data[1] = (value >> 8) & 0xff;
 	data[2] = value & 0xff;
 
 	if (!snd_soc_codec_volatile_register(codec, reg) &&
-	    reg < codec->driver->reg_cache_size)
-		reg_cache[reg] = value;
+		reg < codec->driver->reg_cache_size &&
+		!codec->cache_bypass) {
+		ret = snd_soc_cache_write(codec, reg, value);
+		if (ret < 0)
+			return -1;
+	}
 
 	if (codec->cache_only) {
 		codec->cache_sync = 1;
 		return 0;
 	}
 
-	dev_dbg(codec->dev, "0x%x = 0x%x\n", reg, value);
-
 	if (codec->hw_write(codec->control_data, data, 3) == 3)
 		return 0;
 	else
@@ -271,17 +300,23 @@ static int snd_soc_8_16_write(struct snd_soc_codec *codec, unsigned int reg,
 static unsigned int snd_soc_8_16_read(struct snd_soc_codec *codec,
 				      unsigned int reg)
 {
-	u16 *cache = codec->reg_cache;
+	int ret;
+	unsigned int val;
 
 	if (reg >= codec->driver->reg_cache_size ||
-	    snd_soc_codec_volatile_register(codec, reg)) {
+	    snd_soc_codec_volatile_register(codec, reg) ||
+	    codec->cache_bypass) {
 		if (codec->cache_only)
 			return -1;
 
+		BUG_ON(!codec->hw_read);
 		return codec->hw_read(codec, reg);
-	} else {
-		return cache[reg];
 	}
+
+	ret = snd_soc_cache_read(codec, reg, &val);
+	if (ret < 0)
+		return -1;
+	return val;
 }
 
 #if defined(CONFIG_SPI_MASTER)
@@ -301,7 +336,7 @@ static int snd_soc_8_16_spi_write(void *control_data, const char *data,
 	msg[2] = data[2];
 
 	spi_message_init(&m);
-	memset(&t, 0, (sizeof t));
+	memset(&t, 0, sizeof t);
 
 	t.tx_buf = &msg[0];
 	t.len = len;
@@ -420,24 +455,29 @@ static unsigned int snd_soc_16_8_read_i2c(struct snd_soc_codec *codec,
 static unsigned int snd_soc_16_8_read(struct snd_soc_codec *codec,
 				     unsigned int reg)
 {
-	u8 *cache = codec->reg_cache;
+	int ret;
+	unsigned int val;
 
 	reg &= 0xff;
 	if (reg >= codec->driver->reg_cache_size ||
-		snd_soc_codec_volatile_register(codec, reg)) {
+		snd_soc_codec_volatile_register(codec, reg) ||
+		codec->cache_bypass) {
 			if (codec->cache_only)
 				return -1;
 
+			BUG_ON(!codec->hw_read);
 			return codec->hw_read(codec, reg);
 	}
 
-	return cache[reg];
+	ret = snd_soc_cache_read(codec, reg, &val);
+	if (ret < 0)
+		return -1;
+	return val;
 }
 
 static int snd_soc_16_8_write(struct snd_soc_codec *codec, unsigned int reg,
 			     unsigned int value)
 {
-	u8 *cache = codec->reg_cache;
 	u8 data[3];
 	int ret;
 
@@ -447,16 +487,18 @@ static int snd_soc_16_8_write(struct snd_soc_codec *codec, unsigned int reg,
 
 	reg &= 0xff;
 	if (!snd_soc_codec_volatile_register(codec, reg) &&
-		reg < codec->driver->reg_cache_size)
-			cache[reg] = value;
+		reg < codec->driver->reg_cache_size &&
+		!codec->cache_bypass) {
+		ret = snd_soc_cache_write(codec, reg, value);
+		if (ret < 0)
+			return -1;
+	}
 
 	if (codec->cache_only) {
 		codec->cache_sync = 1;
 		return 0;
 	}
 
-	dev_dbg(codec->dev, "0x%x = 0x%x\n", reg, value);
-
 	ret = codec->hw_write(codec->control_data, data, 3);
 	if (ret == 3)
 		return 0;
@@ -483,7 +525,7 @@ static int snd_soc_16_8_spi_write(void *control_data, const char *data,
 	msg[2] = data[2];
 
 	spi_message_init(&m);
-	memset(&t, 0, (sizeof t));
+	memset(&t, 0, sizeof t);
 
 	t.tx_buf = &msg[0];
 	t.len = len;
@@ -534,23 +576,29 @@ static unsigned int snd_soc_16_16_read_i2c(struct snd_soc_codec *codec,
 static unsigned int snd_soc_16_16_read(struct snd_soc_codec *codec,
 				       unsigned int reg)
 {
-	u16 *cache = codec->reg_cache;
+	int ret;
+	unsigned int val;
 
 	if (reg >= codec->driver->reg_cache_size ||
-	    snd_soc_codec_volatile_register(codec, reg)) {
+	    snd_soc_codec_volatile_register(codec, reg) ||
+	    codec->cache_bypass) {
 		if (codec->cache_only)
 			return -1;
 
+		BUG_ON(!codec->hw_read);
 		return codec->hw_read(codec, reg);
 	}
 
-	return cache[reg];
+	ret = snd_soc_cache_read(codec, reg, &val);
+	if (ret < 0)
+		return -1;
+
+	return val;
 }
 
 static int snd_soc_16_16_write(struct snd_soc_codec *codec, unsigned int reg,
 			       unsigned int value)
 {
-	u16 *cache = codec->reg_cache;
 	u8 data[4];
 	int ret;
 
@@ -560,16 +608,18 @@ static int snd_soc_16_16_write(struct snd_soc_codec *codec, unsigned int reg,
 	data[3] = value & 0xff;
 
 	if (!snd_soc_codec_volatile_register(codec, reg) &&
-		reg < codec->driver->reg_cache_size)
-			cache[reg] = value;
+		reg < codec->driver->reg_cache_size &&
+		!codec->cache_bypass) {
+		ret = snd_soc_cache_write(codec, reg, value);
+		if (ret < 0)
+			return -1;
+	}
 
 	if (codec->cache_only) {
 		codec->cache_sync = 1;
 		return 0;
 	}
 
-	dev_dbg(codec->dev, "0x%x = 0x%x\n", reg, value);
-
 	ret = codec->hw_write(codec->control_data, data, 4);
 	if (ret == 4)
 		return 0;
@@ -597,7 +647,7 @@ static int snd_soc_16_16_spi_write(void *control_data, const char *data,
 	msg[3] = data[3];
 
 	spi_message_init(&m);
-	memset(&t, 0, (sizeof t));
+	memset(&t, 0, sizeof t);
 
 	t.tx_buf = &msg[0];
 	t.len = len;
@@ -692,8 +742,8 @@ int snd_soc_codec_set_cache_io(struct snd_soc_codec *codec,
 		return -EINVAL;
 	}
 
-	codec->driver->write = io_types[i].write;
-	codec->driver->read = io_types[i].read;
+	codec->write = io_types[i].write;
+	codec->read = io_types[i].read;
 
 	switch (control) {
 	case SND_SOC_CUSTOM:
@@ -724,3 +774,906 @@ int snd_soc_codec_set_cache_io(struct snd_soc_codec *codec,
 	return 0;
 }
 EXPORT_SYMBOL_GPL(snd_soc_codec_set_cache_io);
+
+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)
+{
+	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;
+}
+
+struct snd_soc_rbtree_node {
+	struct rb_node node;
+	unsigned int reg;
+	unsigned int value;
+	unsigned int defval;
+} __attribute__ ((packed));
+
+struct snd_soc_rbtree_ctx {
+	struct rb_root root;
+};
+
+static struct snd_soc_rbtree_node *snd_soc_rbtree_lookup(
+	struct rb_root *root, unsigned int reg)
+{
+	struct rb_node *node;
+	struct snd_soc_rbtree_node *rbnode;
+
+	node = root->rb_node;
+	while (node) {
+		rbnode = container_of(node, struct snd_soc_rbtree_node, node);
+		if (rbnode->reg < reg)
+			node = node->rb_left;
+		else if (rbnode->reg > reg)
+			node = node->rb_right;
+		else
+			return rbnode;
+	}
+
+	return NULL;
+}
+
+static int snd_soc_rbtree_insert(struct rb_root *root,
+				 struct snd_soc_rbtree_node *rbnode)
+{
+	struct rb_node **new, *parent;
+	struct snd_soc_rbtree_node *rbnode_tmp;
+
+	parent = NULL;
+	new = &root->rb_node;
+	while (*new) {
+		rbnode_tmp = container_of(*new, struct snd_soc_rbtree_node,
+					  node);
+		parent = *new;
+		if (rbnode_tmp->reg < rbnode->reg)
+			new = &((*new)->rb_left);
+		else if (rbnode_tmp->reg > rbnode->reg)
+			new = &((*new)->rb_right);
+		else
+			return 0;
+	}
+
+	/* insert the node into the rbtree */
+	rb_link_node(&rbnode->node, parent, new);
+	rb_insert_color(&rbnode->node, root);
+
+	return 1;
+}
+
+static int snd_soc_rbtree_cache_sync(struct snd_soc_codec *codec)
+{
+	struct snd_soc_rbtree_ctx *rbtree_ctx;
+	struct rb_node *node;
+	struct snd_soc_rbtree_node *rbnode;
+	unsigned int val;
+	int ret;
+
+	rbtree_ctx = codec->reg_cache;
+	for (node = rb_first(&rbtree_ctx->root); node; node = rb_next(node)) {
+		rbnode = rb_entry(node, struct snd_soc_rbtree_node, node);
+		if (rbnode->value == rbnode->defval)
+			continue;
+		ret = snd_soc_cache_read(codec, rbnode->reg, &val);
+		if (ret)
+			return ret;
+		codec->cache_bypass = 1;
+		ret = snd_soc_write(codec, rbnode->reg, val);
+		codec->cache_bypass = 0;
+		if (ret)
+			return ret;
+		dev_dbg(codec->dev, "Synced register %#x, value = %#x\n",
+			rbnode->reg, val);
+	}
+
+	return 0;
+}
+
+static int snd_soc_rbtree_cache_write(struct snd_soc_codec *codec,
+				      unsigned int reg, unsigned int value)
+{
+	struct snd_soc_rbtree_ctx *rbtree_ctx;
+	struct snd_soc_rbtree_node *rbnode;
+
+	rbtree_ctx = codec->reg_cache;
+	rbnode = snd_soc_rbtree_lookup(&rbtree_ctx->root, reg);
+	if (rbnode) {
+		if (rbnode->value == value)
+			return 0;
+		rbnode->value = value;
+	} else {
+		/* bail out early, no need to create the rbnode yet */
+		if (!value)
+			return 0;
+		/*
+		 * for uninitialized registers whose value is changed
+		 * from the default zero, create an rbnode and insert
+		 * it into the tree.
+		 */
+		rbnode = kzalloc(sizeof *rbnode, GFP_KERNEL);
+		if (!rbnode)
+			return -ENOMEM;
+		rbnode->reg = reg;
+		rbnode->value = value;
+		snd_soc_rbtree_insert(&rbtree_ctx->root, rbnode);
+	}
+
+	return 0;
+}
+
+static int snd_soc_rbtree_cache_read(struct snd_soc_codec *codec,
+				     unsigned int reg, unsigned int *value)
+{
+	struct snd_soc_rbtree_ctx *rbtree_ctx;
+	struct snd_soc_rbtree_node *rbnode;
+
+	rbtree_ctx = codec->reg_cache;
+	rbnode = snd_soc_rbtree_lookup(&rbtree_ctx->root, reg);
+	if (rbnode) {
+		*value = rbnode->value;
+	} else {
+		/* uninitialized registers default to 0 */
+		*value = 0;
+	}
+
+	return 0;
+}
+
+static int snd_soc_rbtree_cache_exit(struct snd_soc_codec *codec)
+{
+	struct rb_node *next;
+	struct snd_soc_rbtree_ctx *rbtree_ctx;
+	struct snd_soc_rbtree_node *rbtree_node;
+
+	/* if we've already been called then just return */
+	rbtree_ctx = codec->reg_cache;
+	if (!rbtree_ctx)
+		return 0;
+
+	/* free up the rbtree */
+	next = rb_first(&rbtree_ctx->root);
+	while (next) {
+		rbtree_node = rb_entry(next, struct snd_soc_rbtree_node, node);
+		next = rb_next(&rbtree_node->node);
+		rb_erase(&rbtree_node->node, &rbtree_ctx->root);
+		kfree(rbtree_node);
+	}
+
+	/* release the resources */
+	kfree(codec->reg_cache);
+	codec->reg_cache = NULL;
+
+	return 0;
+}
+
+static int snd_soc_rbtree_cache_init(struct snd_soc_codec *codec)
+{
+	struct snd_soc_rbtree_node *rbtree_node;
+	struct snd_soc_rbtree_ctx *rbtree_ctx;
+	unsigned int val;
+	unsigned int word_size;
+	int i;
+	int ret;
+
+	codec->reg_cache = kmalloc(sizeof *rbtree_ctx, GFP_KERNEL);
+	if (!codec->reg_cache)
+		return -ENOMEM;
+
+	rbtree_ctx = codec->reg_cache;
+	rbtree_ctx->root = RB_ROOT;
+
+	if (!codec->reg_def_copy)
+		return 0;
+
+	/*
+	 * populate the rbtree with the initialized registers.  All other
+	 * registers will be inserted when they are first modified.
+	 */
+	word_size = codec->driver->reg_word_size;
+	for (i = 0; i < codec->driver->reg_cache_size; ++i) {
+		val = snd_soc_get_cache_val(codec->reg_def_copy, i, word_size);
+		if (!val)
+			continue;
+		rbtree_node = kzalloc(sizeof *rbtree_node, GFP_KERNEL);
+		if (!rbtree_node) {
+			ret = -ENOMEM;
+			snd_soc_cache_exit(codec);
+			break;
+		}
+		rbtree_node->reg = i;
+		rbtree_node->value = val;
+		rbtree_node->defval = val;
+		snd_soc_rbtree_insert(&rbtree_ctx->root, rbtree_node);
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_SND_SOC_CACHE_LZO
+struct snd_soc_lzo_ctx {
+	void *wmem;
+	void *dst;
+	const void *src;
+	size_t src_len;
+	size_t dst_len;
+	size_t decompressed_size;
+	unsigned long *sync_bmp;
+	int sync_bmp_nbits;
+};
+
+#define LZO_BLOCK_NUM 8
+static int snd_soc_lzo_block_count(void)
+{
+	return LZO_BLOCK_NUM;
+}
+
+static int snd_soc_lzo_prepare(struct snd_soc_lzo_ctx *lzo_ctx)
+{
+	lzo_ctx->wmem = kmalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL);
+	if (!lzo_ctx->wmem)
+		return -ENOMEM;
+	return 0;
+}
+
+static int snd_soc_lzo_compress(struct snd_soc_lzo_ctx *lzo_ctx)
+{
+	size_t compress_size;
+	int ret;
+
+	ret = lzo1x_1_compress(lzo_ctx->src, lzo_ctx->src_len,
+			       lzo_ctx->dst, &compress_size, lzo_ctx->wmem);
+	if (ret != LZO_E_OK || compress_size > lzo_ctx->dst_len)
+		return -EINVAL;
+	lzo_ctx->dst_len = compress_size;
+	return 0;
+}
+
+static int snd_soc_lzo_decompress(struct snd_soc_lzo_ctx *lzo_ctx)
+{
+	size_t dst_len;
+	int ret;
+
+	dst_len = lzo_ctx->dst_len;
+	ret = lzo1x_decompress_safe(lzo_ctx->src, lzo_ctx->src_len,
+				    lzo_ctx->dst, &dst_len);
+	if (ret != LZO_E_OK || dst_len != lzo_ctx->dst_len)
+		return -EINVAL;
+	return 0;
+}
+
+static int snd_soc_lzo_compress_cache_block(struct snd_soc_codec *codec,
+		struct snd_soc_lzo_ctx *lzo_ctx)
+{
+	int ret;
+
+	lzo_ctx->dst_len = lzo1x_worst_compress(PAGE_SIZE);
+	lzo_ctx->dst = kmalloc(lzo_ctx->dst_len, GFP_KERNEL);
+	if (!lzo_ctx->dst) {
+		lzo_ctx->dst_len = 0;
+		return -ENOMEM;
+	}
+
+	ret = snd_soc_lzo_compress(lzo_ctx);
+	if (ret < 0)
+		return ret;
+	return 0;
+}
+
+static int snd_soc_lzo_decompress_cache_block(struct snd_soc_codec *codec,
+		struct snd_soc_lzo_ctx *lzo_ctx)
+{
+	int ret;
+
+	lzo_ctx->dst_len = lzo_ctx->decompressed_size;
+	lzo_ctx->dst = kmalloc(lzo_ctx->dst_len, GFP_KERNEL);
+	if (!lzo_ctx->dst) {
+		lzo_ctx->dst_len = 0;
+		return -ENOMEM;
+	}
+
+	ret = snd_soc_lzo_decompress(lzo_ctx);
+	if (ret < 0)
+		return ret;
+	return 0;
+}
+
+static inline int snd_soc_lzo_get_blkindex(struct snd_soc_codec *codec,
+		unsigned int reg)
+{
+	const struct snd_soc_codec_driver *codec_drv;
+
+	codec_drv = codec->driver;
+	return (reg * codec_drv->reg_word_size) /
+	       DIV_ROUND_UP(codec->reg_size, snd_soc_lzo_block_count());
+}
+
+static inline int snd_soc_lzo_get_blkpos(struct snd_soc_codec *codec,
+		unsigned int reg)
+{
+	const struct snd_soc_codec_driver *codec_drv;
+
+	codec_drv = codec->driver;
+	return reg % (DIV_ROUND_UP(codec->reg_size, snd_soc_lzo_block_count()) /
+		      codec_drv->reg_word_size);
+}
+
+static inline int snd_soc_lzo_get_blksize(struct snd_soc_codec *codec)
+{
+	const struct snd_soc_codec_driver *codec_drv;
+
+	codec_drv = codec->driver;
+	return DIV_ROUND_UP(codec->reg_size, snd_soc_lzo_block_count());
+}
+
+static int snd_soc_lzo_cache_sync(struct snd_soc_codec *codec)
+{
+	struct snd_soc_lzo_ctx **lzo_blocks;
+	unsigned int val;
+	int i;
+	int ret;
+
+	lzo_blocks = codec->reg_cache;
+	for_each_set_bit(i, lzo_blocks[0]->sync_bmp, lzo_blocks[0]->sync_bmp_nbits) {
+		ret = snd_soc_cache_read(codec, i, &val);
+		if (ret)
+			return ret;
+		codec->cache_bypass = 1;
+		ret = snd_soc_write(codec, i, val);
+		codec->cache_bypass = 0;
+		if (ret)
+			return ret;
+		dev_dbg(codec->dev, "Synced register %#x, value = %#x\n",
+			i, val);
+	}
+
+	return 0;
+}
+
+static int snd_soc_lzo_cache_write(struct snd_soc_codec *codec,
+				   unsigned int reg, unsigned int value)
+{
+	struct snd_soc_lzo_ctx *lzo_block, **lzo_blocks;
+	int ret, blkindex, blkpos;
+	size_t blksize, tmp_dst_len;
+	void *tmp_dst;
+
+	/* index of the compressed lzo block */
+	blkindex = snd_soc_lzo_get_blkindex(codec, reg);
+	/* register index within the decompressed block */
+	blkpos = snd_soc_lzo_get_blkpos(codec, reg);
+	/* size of the compressed block */
+	blksize = snd_soc_lzo_get_blksize(codec);
+	lzo_blocks = codec->reg_cache;
+	lzo_block = lzo_blocks[blkindex];
+
+	/* save the pointer and length of the compressed block */
+	tmp_dst = lzo_block->dst;
+	tmp_dst_len = lzo_block->dst_len;
+
+	/* prepare the source to be the compressed block */
+	lzo_block->src = lzo_block->dst;
+	lzo_block->src_len = lzo_block->dst_len;
+
+	/* decompress the block */
+	ret = snd_soc_lzo_decompress_cache_block(codec, lzo_block);
+	if (ret < 0) {
+		kfree(lzo_block->dst);
+		goto out;
+	}
+
+	/* write the new value to the cache */
+	if (snd_soc_set_cache_val(lzo_block->dst, blkpos, value,
+				  codec->driver->reg_word_size)) {
+		kfree(lzo_block->dst);
+		goto out;
+	}
+
+	/* prepare the source to be the decompressed block */
+	lzo_block->src = lzo_block->dst;
+	lzo_block->src_len = lzo_block->dst_len;
+
+	/* compress the block */
+	ret = snd_soc_lzo_compress_cache_block(codec, lzo_block);
+	if (ret < 0) {
+		kfree(lzo_block->dst);
+		kfree(lzo_block->src);
+		goto out;
+	}
+
+	/* set the bit so we know we have to sync this register */
+	set_bit(reg, lzo_block->sync_bmp);
+	kfree(tmp_dst);
+	kfree(lzo_block->src);
+	return 0;
+out:
+	lzo_block->dst = tmp_dst;
+	lzo_block->dst_len = tmp_dst_len;
+	return ret;
+}
+
+static int snd_soc_lzo_cache_read(struct snd_soc_codec *codec,
+				  unsigned int reg, unsigned int *value)
+{
+	struct snd_soc_lzo_ctx *lzo_block, **lzo_blocks;
+	int ret, blkindex, blkpos;
+	size_t blksize, tmp_dst_len;
+	void *tmp_dst;
+
+	*value = 0;
+	/* index of the compressed lzo block */
+	blkindex = snd_soc_lzo_get_blkindex(codec, reg);
+	/* register index within the decompressed block */
+	blkpos = snd_soc_lzo_get_blkpos(codec, reg);
+	/* size of the compressed block */
+	blksize = snd_soc_lzo_get_blksize(codec);
+	lzo_blocks = codec->reg_cache;
+	lzo_block = lzo_blocks[blkindex];
+
+	/* save the pointer and length of the compressed block */
+	tmp_dst = lzo_block->dst;
+	tmp_dst_len = lzo_block->dst_len;
+
+	/* prepare the source to be the compressed block */
+	lzo_block->src = lzo_block->dst;
+	lzo_block->src_len = lzo_block->dst_len;
+
+	/* decompress the block */
+	ret = snd_soc_lzo_decompress_cache_block(codec, lzo_block);
+	if (ret >= 0)
+		/* fetch the value from the cache */
+		*value = snd_soc_get_cache_val(lzo_block->dst, blkpos,
+					       codec->driver->reg_word_size);
+
+	kfree(lzo_block->dst);
+	/* restore the pointer and length of the compressed block */
+	lzo_block->dst = tmp_dst;
+	lzo_block->dst_len = tmp_dst_len;
+	return 0;
+}
+
+static int snd_soc_lzo_cache_exit(struct snd_soc_codec *codec)
+{
+	struct snd_soc_lzo_ctx **lzo_blocks;
+	int i, blkcount;
+
+	lzo_blocks = codec->reg_cache;
+	if (!lzo_blocks)
+		return 0;
+
+	blkcount = snd_soc_lzo_block_count();
+	/*
+	 * the pointer to the bitmap used for syncing the cache
+	 * is shared amongst all lzo_blocks.  Ensure it is freed
+	 * only once.
+	 */
+	if (lzo_blocks[0])
+		kfree(lzo_blocks[0]->sync_bmp);
+	for (i = 0; i < blkcount; ++i) {
+		if (lzo_blocks[i]) {
+			kfree(lzo_blocks[i]->wmem);
+			kfree(lzo_blocks[i]->dst);
+		}
+		/* each lzo_block is a pointer returned by kmalloc or NULL */
+		kfree(lzo_blocks[i]);
+	}
+	kfree(lzo_blocks);
+	codec->reg_cache = NULL;
+	return 0;
+}
+
+static int snd_soc_lzo_cache_init(struct snd_soc_codec *codec)
+{
+	struct snd_soc_lzo_ctx **lzo_blocks;
+	size_t bmp_size;
+	const struct snd_soc_codec_driver *codec_drv;
+	int ret, tofree, i, blksize, blkcount;
+	const char *p, *end;
+	unsigned long *sync_bmp;
+
+	ret = 0;
+	codec_drv = codec->driver;
+
+	/*
+	 * If we have not been given a default register cache
+	 * then allocate a dummy zero-ed out region, compress it
+	 * and remember to free it afterwards.
+	 */
+	tofree = 0;
+	if (!codec->reg_def_copy)
+		tofree = 1;
+
+	if (!codec->reg_def_copy) {
+		codec->reg_def_copy = kzalloc(codec->reg_size, GFP_KERNEL);
+		if (!codec->reg_def_copy)
+			return -ENOMEM;
+	}
+
+	blkcount = snd_soc_lzo_block_count();
+	codec->reg_cache = kzalloc(blkcount * sizeof *lzo_blocks,
+				   GFP_KERNEL);
+	if (!codec->reg_cache) {
+		ret = -ENOMEM;
+		goto err_tofree;
+	}
+	lzo_blocks = codec->reg_cache;
+
+	/*
+	 * allocate a bitmap to be used when syncing the cache with
+	 * the hardware.  Each time a register is modified, the corresponding
+	 * bit is set in the bitmap, so we know that we have to sync
+	 * that register.
+	 */
+	bmp_size = codec_drv->reg_cache_size;
+	sync_bmp = kmalloc(BITS_TO_LONGS(bmp_size) * sizeof(long),
+			   GFP_KERNEL);
+	if (!sync_bmp) {
+		ret = -ENOMEM;
+		goto err;
+	}
+	bitmap_zero(sync_bmp, bmp_size);
+
+	/* allocate the lzo blocks and initialize them */
+	for (i = 0; i < blkcount; ++i) {
+		lzo_blocks[i] = kzalloc(sizeof **lzo_blocks,
+					GFP_KERNEL);
+		if (!lzo_blocks[i]) {
+			kfree(sync_bmp);
+			ret = -ENOMEM;
+			goto err;
+		}
+		lzo_blocks[i]->sync_bmp = sync_bmp;
+		lzo_blocks[i]->sync_bmp_nbits = bmp_size;
+		/* alloc the working space for the compressed block */
+		ret = snd_soc_lzo_prepare(lzo_blocks[i]);
+		if (ret < 0)
+			goto err;
+	}
+
+	blksize = snd_soc_lzo_get_blksize(codec);
+	p = codec->reg_def_copy;
+	end = codec->reg_def_copy + codec->reg_size;
+	/* compress the register map and fill the lzo blocks */
+	for (i = 0; i < blkcount; ++i, p += blksize) {
+		lzo_blocks[i]->src = p;
+		if (p + blksize > end)
+			lzo_blocks[i]->src_len = end - p;
+		else
+			lzo_blocks[i]->src_len = blksize;
+		ret = snd_soc_lzo_compress_cache_block(codec,
+						       lzo_blocks[i]);
+		if (ret < 0)
+			goto err;
+		lzo_blocks[i]->decompressed_size =
+			lzo_blocks[i]->src_len;
+	}
+
+	if (tofree) {
+		kfree(codec->reg_def_copy);
+		codec->reg_def_copy = NULL;
+	}
+	return 0;
+err:
+	snd_soc_cache_exit(codec);
+err_tofree:
+	if (tofree) {
+		kfree(codec->reg_def_copy);
+		codec->reg_def_copy = NULL;
+	}
+	return ret;
+}
+#endif
+
+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;
+		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)
+{
+	const struct snd_soc_codec_driver *codec_drv;
+
+	codec_drv = codec->driver;
+
+	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
+	},
+#ifdef CONFIG_SND_SOC_CACHE_LZO
+	{
+		.id = SND_SOC_LZO_COMPRESSION,
+		.name = "LZO",
+		.init = snd_soc_lzo_cache_init,
+		.exit = snd_soc_lzo_cache_exit,
+		.read = snd_soc_lzo_cache_read,
+		.write = snd_soc_lzo_cache_write,
+		.sync = snd_soc_lzo_cache_sync
+	},
+#endif
+	{
+		.id = SND_SOC_RBTREE_COMPRESSION,
+		.name = "rbtree",
+		.init = snd_soc_rbtree_cache_init,
+		.exit = snd_soc_rbtree_cache_exit,
+		.read = snd_soc_rbtree_cache_read,
+		.write = snd_soc_rbtree_cache_write,
+		.sync = snd_soc_rbtree_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 -EINVAL;
+}
+
+/*
+ * 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 -EINVAL;
+}
+
+/**
+ * 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 -EINVAL;
+}
+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 -EINVAL;
+}
+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 -EINVAL;
+
+	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);