Merge remote-tracking branch 'regmap/topic/cache' into regmap-next

1 files changed, 30 insertions, 25 deletions

diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c
index 44e6a48019a5..d815929ba745 100644
--- a/drivers/base/regmap/regcache.c
+++ b/drivers/base/regmap/regcache.c
@@ -36,6 +36,23 @@ static int regcache_hw_init(struct regmap *map)
         if (!map->num_reg_defaults_raw)
                 return -EINVAL;
 
+        /* calculate the size of reg_defaults */
+        for (count = 0, i = 0; i < map->num_reg_defaults_raw; i++)
+                if (!regmap_volatile(map, i * map->reg_stride))
+                        count++;
+
+        /* all registers are volatile, so just bypass */
+        if (!count) {
+                map->cache_bypass = true;
+                return 0;
+        }
+
+        map->num_reg_defaults = count;
+        map->reg_defaults = kmalloc_array(count, sizeof(struct reg_default),
+                                          GFP_KERNEL);
+        if (!map->reg_defaults)
+                return -ENOMEM;
+
         if (!map->reg_defaults_raw) {
                 u32 cache_bypass = map->cache_bypass;
                 dev_warn(map->dev, "No cache defaults, reading back from HW\n");
@@ -43,40 +60,25 @@ static int regcache_hw_init(struct regmap *map)
                 /* Bypass the cache access till data read from HW*/
                 map->cache_bypass = 1;
                 tmp_buf = kmalloc(map->cache_size_raw, GFP_KERNEL);
-                if (!tmp_buf)
-                        return -ENOMEM;
+                if (!tmp_buf) {
+                        ret = -ENOMEM;
+                        goto err_free;
+                }
                 ret = regmap_raw_read(map, 0, tmp_buf,
                                       map->num_reg_defaults_raw);
                 map->cache_bypass = cache_bypass;
-                if (ret < 0) {
-                        kfree(tmp_buf);
-                        return ret;
-                }
+                if (ret < 0)
+                        goto err_cache_free;
+
                 map->reg_defaults_raw = tmp_buf;
                 map->cache_free = 1;
         }
 
-        /* calculate the size of reg_defaults */
-        for (count = 0, i = 0; i < map->num_reg_defaults_raw; i++) {
-                val = regcache_get_val(map, map->reg_defaults_raw, i);
-                if (regmap_volatile(map, i * map->reg_stride))
-                        continue;
-                count++;
-        }
-
-        map->reg_defaults = kmalloc(count * sizeof(struct reg_default),
-                                      GFP_KERNEL);
-        if (!map->reg_defaults) {
-                ret = -ENOMEM;
-                goto err_free;
-        }
-
         /* fill the reg_defaults */
-        map->num_reg_defaults = count;
         for (i = 0, j = 0; i < map->num_reg_defaults_raw; i++) {
-                val = regcache_get_val(map, map->reg_defaults_raw, i);
                 if (regmap_volatile(map, i * map->reg_stride))
                         continue;
+                val = regcache_get_val(map, map->reg_defaults_raw, i);
                 map->reg_defaults[j].reg = i * map->reg_stride;
                 map->reg_defaults[j].def = val;
                 j++;
@@ -84,9 +86,10 @@ static int regcache_hw_init(struct regmap *map)
 
         return 0;
 
+err_cache_free:
+        kfree(tmp_buf);
 err_free:
-        if (map->cache_free)
-                kfree(map->reg_defaults_raw);
+        kfree(map->reg_defaults);
 
         return ret;
 }
@@ -150,6 +153,8 @@ int regcache_init(struct regmap *map, const struct regmap_config *config)
                 ret = regcache_hw_init(map);
                 if (ret < 0)
                         return ret;
+                if (map->cache_bypass)
+                        return 0;
         }
 
         if (!map->max_register)