diff options
Diffstat (limited to 'sound')
| -rw-r--r-- | sound/soc/soc-cache.c | 232 |
1 files changed, 232 insertions, 0 deletions
diff --git a/sound/soc/soc-cache.c b/sound/soc/soc-cache.c index 4581bf100222..6c0589e3fefb 100644 --- a/sound/soc/soc-cache.c +++ b/sound/soc/soc-cache.c @@ -16,6 +16,7 @@ #include <sound/soc.h> #include <linux/lzo.h> #include <linux/bitmap.h> +#include <linux/rbtree.h> static unsigned int snd_soc_4_12_read(struct snd_soc_codec *codec, unsigned int reg) @@ -760,6 +761,229 @@ int snd_soc_codec_set_cache_io(struct snd_soc_codec *codec, } EXPORT_SYMBOL_GPL(snd_soc_codec_set_cache_io); +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; + + 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; + snd_soc_cache_read(codec, rbnode->reg, &val); + snd_soc_write(codec, rbnode->reg, val); + 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_ctx *rbtree_ctx; + + 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->driver->reg_cache_default) + return 0; + +/* + * populate the rbtree with the initialized registers. All other + * registers will be inserted into the tree when they are first written. + * + * The reasoning behind this, is that we need to step through and + * dereference the cache in u8/u16 increments without sacrificing + * portability. This could also be done using memcpy() but that would + * be slightly more cryptic. + */ +#define snd_soc_rbtree_populate(cache) \ +({ \ + int ret, i; \ + struct snd_soc_rbtree_node *rbtree_node; \ + \ + ret = 0; \ + cache = codec->driver->reg_cache_default; \ + for (i = 0; i < codec->driver->reg_cache_size; ++i) { \ + if (!cache[i]) \ + 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 = cache[i]; \ + rbtree_node->defval = cache[i]; \ + snd_soc_rbtree_insert(&rbtree_ctx->root, \ + rbtree_node); \ + } \ + ret; \ +}) + + switch (codec->driver->reg_word_size) { + case 1: { + const u8 *cache; + + return snd_soc_rbtree_populate(cache); + } + case 2: { + const u16 *cache; + + return snd_soc_rbtree_populate(cache); + } + default: + BUG(); + } + + return 0; +} + struct snd_soc_lzo_ctx { void *wmem; void *dst; @@ -1296,6 +1520,14 @@ static const struct snd_soc_cache_ops cache_types[] = { .read = snd_soc_lzo_cache_read, .write = snd_soc_lzo_cache_write, .sync = snd_soc_lzo_cache_sync + }, + { + .id = SND_SOC_RBTREE_COMPRESSION, + .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 } }; |