regmap: rbtree-cache: Move cached rbnode handling into lookup function

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@metafoo.de>
Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 18 insertions, 43 deletions

diff --git a/drivers/base/regmap/regcache-rbtree.c b/drivers/base/regmap/regcache-rbtree.c
index 52669dec73b3..de32ced1917a 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)