[PATCH 2/2] regmap: rbtree-cache: Move cached rbnode handling into lookup function

From: Lars-Peter Clausen
Date: Tue Sep 27 2011 - 14:17:18 EST


Move the handling of the cached rbnode into regcache_rbtree_lookup. This allows
us to remove of some duplicated code sections in regcache_rbtree_read and
regcache_rbtree_write.

Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
---
drivers/base/regmap/regcache-rbtree.c | 61 ++++++++++-----------------------
1 files changed, 18 insertions(+), 43 deletions(-)

diff --git a/drivers/base/regmap/regcache-rbtree.c b/drivers/base/regmap/regcache-rbtree.c
index 52669de..de32ced 100644
--- a/drivers/base/regmap/regcache-rbtree.c
+++ b/drivers/base/regmap/regcache-rbtree.c
@@ -56,23 +56,33 @@ static void regcache_rbtree_set_register(struct regcache_rbtree_node *rbnode,
regcache_set_val(rbnode->block, idx, val, word_size);
}

-static struct regcache_rbtree_node *regcache_rbtree_lookup(
- struct rb_root *root, unsigned int reg)
+static struct regcache_rbtree_node *regcache_rbtree_lookup(struct regmap *map,
+ unsigned int reg)
{
+ struct regcache_rbtree_ctx *rbtree_ctx = map->cache;
struct rb_node *node;
struct regcache_rbtree_node *rbnode;
unsigned int base_reg, top_reg;

- node = root->rb_node;
+ rbnode = rbtree_ctx->cached_rbnode;
+ if (rbnode) {
+ regcache_rbtree_get_base_top_reg(rbnode, &base_reg, &top_reg);
+ if (reg >= base_reg && reg <= top_reg)
+ return rbnode;
+ }
+
+ node = rbtree_ctx->root.rb_node;
while (node) {
rbnode = container_of(node, struct regcache_rbtree_node, node);
regcache_rbtree_get_base_top_reg(rbnode, &base_reg, &top_reg);
- if (reg >= base_reg && reg <= top_reg)
+ if (reg >= base_reg && reg <= top_reg) {
+ rbtree_ctx->cached_rbnode = rbnode;
return rbnode;
- else if (reg > top_reg)
+ } else if (reg > top_reg) {
node = node->rb_right;
- else if (reg < base_reg)
+ } else if (reg < base_reg) {
node = node->rb_left;
+ }
}

return NULL;
@@ -174,32 +184,14 @@ static int regcache_rbtree_exit(struct regmap *map)
static int regcache_rbtree_read(struct regmap *map,
unsigned int reg, unsigned int *value)
{
- struct regcache_rbtree_ctx *rbtree_ctx;
struct regcache_rbtree_node *rbnode;
- unsigned int base_reg, top_reg;
unsigned int reg_tmp;

- rbtree_ctx = map->cache;
- /* look up the required register in the cached rbnode */
- rbnode = rbtree_ctx->cached_rbnode;
- if (rbnode) {
- regcache_rbtree_get_base_top_reg(rbnode, &base_reg, &top_reg);
- if (reg >= base_reg && reg <= top_reg) {
- reg_tmp = reg - base_reg;
- *value = regcache_rbtree_get_register(rbnode, reg_tmp,
- map->cache_word_size);
- return 0;
- }
- }
- /* if we can't locate it in the cached rbnode we'll have
- * to traverse the rbtree looking for it.
- */
- rbnode = regcache_rbtree_lookup(&rbtree_ctx->root, reg);
+ rbnode = regcache_rbtree_lookup(map, reg);
if (rbnode) {
reg_tmp = reg - rbnode->base_reg;
*value = regcache_rbtree_get_register(rbnode, reg_tmp,
map->cache_word_size);
- rbtree_ctx->cached_rbnode = rbnode;
} else {
/* uninitialized registers default to 0 */
*value = 0;
@@ -243,31 +235,15 @@ static int regcache_rbtree_write(struct regmap *map, unsigned int reg,
struct rb_node *node;
unsigned int val;
unsigned int reg_tmp;
- unsigned int base_reg, top_reg;
unsigned int pos;
int i;
int ret;

rbtree_ctx = map->cache;
- /* look up the required register in the cached rbnode */
- rbnode = rbtree_ctx->cached_rbnode;
- if (rbnode) {
- regcache_rbtree_get_base_top_reg(rbnode, &base_reg, &top_reg);
- if (reg >= base_reg && reg <= top_reg) {
- reg_tmp = reg - base_reg;
- val = regcache_rbtree_get_register(rbnode, reg_tmp,
- map->cache_word_size);
- if (val == value)
- return 0;
- regcache_rbtree_set_register(rbnode, reg_tmp, value,
- map->cache_word_size);
- return 0;
- }
- }
/* if we can't locate it in the cached rbnode we'll have
* to traverse the rbtree looking for it.
*/
- rbnode = regcache_rbtree_lookup(&rbtree_ctx->root, reg);
+ rbnode = regcache_rbtree_lookup(map, reg);
if (rbnode) {
reg_tmp = reg - rbnode->base_reg;
val = regcache_rbtree_get_register(rbnode, reg_tmp,
@@ -276,7 +252,6 @@ static int regcache_rbtree_write(struct regmap *map, unsigned int reg,
return 0;
regcache_rbtree_set_register(rbnode, reg_tmp, value,
map->cache_word_size);
- rbtree_ctx->cached_rbnode = rbnode;
} else {
/* bail out early, no need to create the rbnode yet */
if (!value)
--
1.7.2.5

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