1 files changed, 128 insertions, 12 deletions

diff --git a/drivers/base/regmap/regcache-maple.c b/drivers/base/regmap/regcache-maple.c
index c2e3a0f6c218..283c2e02a298 100644
--- a/drivers/base/regmap/regcache-maple.c
+++ b/drivers/base/regmap/regcache-maple.c
@@ -186,6 +186,55 @@ out_unlocked:
 	return ret;
 }
 
+static int regcache_maple_sync_block(struct regmap *map, unsigned long *entry,
+				     struct ma_state *mas,
+				     unsigned int min, unsigned int max)
+{
+	void *buf;
+	unsigned long r;
+	size_t val_bytes = map->format.val_bytes;
+	int ret = 0;
+
+	mas_pause(mas);
+	rcu_read_unlock();
+
+	/*
+	 * Use a raw write if writing more than one register to a
+	 * device that supports raw writes to reduce transaction
+	 * overheads.
+	 */
+	if (max - min > 1 && regmap_can_raw_write(map)) {
+		buf = kmalloc(val_bytes * (max - min), map->alloc_flags);
+		if (!buf) {
+			ret = -ENOMEM;
+			goto out;
+		}
+
+		/* Render the data for a raw write */
+		for (r = min; r < max; r++) {
+			regcache_set_val(map, buf, r - min,
+					 entry[r - mas->index]);
+		}
+
+		ret = _regmap_raw_write(map, min, buf, (max - min) * val_bytes,
+					false);
+
+		kfree(buf);
+	} else {
+		for (r = min; r < max; r++) {
+			ret = _regmap_write(map, r,
+					    entry[r - mas->index]);
+			if (ret != 0)
+				goto out;
+		}
+	}
+
+out:
+	rcu_read_lock();
+
+	return ret;
+}
+
 static int regcache_maple_sync(struct regmap *map, unsigned int min,
 			       unsigned int max)
 {
@@ -194,8 +243,9 @@ static int regcache_maple_sync(struct regmap *map, unsigned int min,
 	MA_STATE(mas, mt, min, max);
 	unsigned long lmin = min;
 	unsigned long lmax = max;
-	unsigned int r;
+	unsigned int r, v, sync_start;
 	int ret;
+	bool sync_needed = false;
 
 	map->cache_bypass = true;
 
@@ -203,18 +253,38 @@ static int regcache_maple_sync(struct regmap *map, unsigned int min,
 
 	mas_for_each(&mas, entry, max) {
 		for (r = max(mas.index, lmin); r <= min(mas.last, lmax); r++) {
-			mas_pause(&mas);
-			rcu_read_unlock();
-			ret = regcache_sync_val(map, r, entry[r - mas.index]);
+			v = entry[r - mas.index];
+
+			if (regcache_reg_needs_sync(map, r, v)) {
+				if (!sync_needed) {
+					sync_start = r;
+					sync_needed = true;
+				}
+				continue;
+			}
+
+			if (!sync_needed)
+				continue;
+
+			ret = regcache_maple_sync_block(map, entry, &mas,
+							sync_start, r);
+			if (ret != 0)
+				goto out;
+			sync_needed = false;
+		}
+
+		if (sync_needed) {
+			ret = regcache_maple_sync_block(map, entry, &mas,
+							sync_start, r);
 			if (ret != 0)
 				goto out;
-			rcu_read_lock();
+			sync_needed = false;
 		}
 	}
 
+out:
 	rcu_read_unlock();
 
-out:
 	map->cache_bypass = false;
 
 	return ret;
@@ -242,11 +312,41 @@ static int regcache_maple_exit(struct regmap *map)
 	return 0;
 }
 
+static int regcache_maple_insert_block(struct regmap *map, int first,
+					int last)
+{
+	struct maple_tree *mt = map->cache;
+	MA_STATE(mas, mt, first, last);
+	unsigned long *entry;
+	int i, ret;
+
+	entry = kcalloc(last - first + 1, sizeof(unsigned long), GFP_KERNEL);
+	if (!entry)
+		return -ENOMEM;
+
+	for (i = 0; i < last - first + 1; i++)
+		entry[i] = map->reg_defaults[first + i].def;
+
+	mas_lock(&mas);
+
+	mas_set_range(&mas, map->reg_defaults[first].reg,
+		      map->reg_defaults[last].reg);
+	ret = mas_store_gfp(&mas, entry, GFP_KERNEL);
+
+	mas_unlock(&mas);
+
+	if (ret)
+		kfree(entry);
+
+	return ret;
+}
+
 static int regcache_maple_init(struct regmap *map)
 {
 	struct maple_tree *mt;
 	int i;
 	int ret;
+	int range_start;
 
 	mt = kmalloc(sizeof(*mt), GFP_KERNEL);
 	if (!mt)
@@ -255,14 +355,30 @@ static int regcache_maple_init(struct regmap *map)
 
 	mt_init(mt);
 
-	for (i = 0; i < map->num_reg_defaults; i++) {
-		ret = regcache_maple_write(map,
-					   map->reg_defaults[i].reg,
-					   map->reg_defaults[i].def);
-		if (ret)
-			goto err;
+	if (!map->num_reg_defaults)
+		return 0;
+
+	range_start = 0;
+
+	/* Scan for ranges of contiguous registers */
+	for (i = 1; i < map->num_reg_defaults; i++) {
+		if (map->reg_defaults[i].reg !=
+		    map->reg_defaults[i - 1].reg + 1) {
+			ret = regcache_maple_insert_block(map, range_start,
+							  i - 1);
+			if (ret != 0)
+				goto err;
+
+			range_start = i;
+		}
 	}
 
+	/* Add the last block */
+	ret = regcache_maple_insert_block(map, range_start,
+					  map->num_reg_defaults - 1);
+	if (ret != 0)
+		goto err;
+
 	return 0;
 
 err: