regmap: cache: Factor out block sync

The idea of holding blocks of registers in device format is shared between
at least rbtree and lzo cache formats so split out the loop that does the
sync from the rbtree code so optimisations on it can be reused.

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

1 files changed, 42 insertions, 0 deletions

diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c
index 0fedf4fa0116..bb317db6818f 100644
--- a/drivers/base/regmap/regcache.c
+++ b/drivers/base/regmap/regcache.c
@@ -544,3 +544,45 @@ int regcache_lookup_reg(struct regmap *map, unsigned int reg)
 	else
 		return -ENOENT;
 }
+
+int regcache_sync_block(struct regmap *map, void *block,
+			unsigned int block_base, unsigned int start,
+			unsigned int end)
+{
+	unsigned int i, regtmp, val;
+	const void *addr;
+	int ret;
+
+	for (i = start; i < end; i++) {
+		regtmp = block_base + (i * map->reg_stride);
+
+		if (!regcache_reg_present(map, regtmp))
+			continue;
+
+		val = regcache_get_val(map, block, i);
+
+		/* Is this the hardware default?  If so skip. */
+		ret = regcache_lookup_reg(map, regtmp);
+		if (ret >= 0 && val == map->reg_defaults[ret].def)
+			continue;
+
+		map->cache_bypass = 1;
+
+		if (regmap_can_raw_write(map)) {
+			addr = regcache_get_val_addr(map, block, i);
+			ret = _regmap_raw_write(map, regtmp, addr,
+						map->format.val_bytes,
+						false);
+		} else {
+			ret = _regmap_write(map, regtmp, val);
+		}
+
+		map->cache_bypass = 0;
+		if (ret != 0)
+			return ret;
+		dev_dbg(map->dev, "Synced register %#x, value %#x\n",
+			regtmp, val);
+	}
+
+	return 0;
+}