2 files changed, 57 insertions, 13 deletions

diff --git a/drivers/base/regmap/regcache-rbtree.c b/drivers/base/regmap/regcache-rbtree.c
index 81751a49d8bf..56486d92c4e7 100644
--- a/drivers/base/regmap/regcache-rbtree.c
+++ b/drivers/base/regmap/regcache-rbtree.c
@@ -296,11 +296,20 @@ static int regcache_rbtree_insert_to_block(struct regmap *map,
 	if (!blk)
 		return -ENOMEM;
 
-	present = krealloc(rbnode->cache_present,
-		    BITS_TO_LONGS(blklen) * sizeof(*present), GFP_KERNEL);
-	if (!present) {
-		kfree(blk);
-		return -ENOMEM;
+	if (BITS_TO_LONGS(blklen) > BITS_TO_LONGS(rbnode->blklen)) {
+		present = krealloc(rbnode->cache_present,
+				   BITS_TO_LONGS(blklen) * sizeof(*present),
+				   GFP_KERNEL);
+		if (!present) {
+			kfree(blk);
+			return -ENOMEM;
+		}
+
+		memset(present + BITS_TO_LONGS(rbnode->blklen), 0,
+		       (BITS_TO_LONGS(blklen) - BITS_TO_LONGS(rbnode->blklen))
+		       * sizeof(*present));
+	} else {
+		present = rbnode->cache_present;
 	}
 
 	/* insert the register value in the correct place in the rbnode block */
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 2cbb4502747d..0a849eeaf952 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -34,7 +34,7 @@
 
 static int _regmap_update_bits(struct regmap *map, unsigned int reg,
 			       unsigned int mask, unsigned int val,
-			       bool *change);
+			       bool *change, bool force_write);
 
 static int _regmap_bus_reg_read(void *context, unsigned int reg,
 				unsigned int *val);
@@ -1178,7 +1178,7 @@ static int _regmap_select_page(struct regmap *map, unsigned int *reg,
 		ret = _regmap_update_bits(map, range->selector_reg,
 					  range->selector_mask,
 					  win_page << range->selector_shift,
-					  &page_chg);
+					  &page_chg, false);
 
 		map->work_buf = orig_work_buf;
 
@@ -1624,6 +1624,18 @@ int regmap_fields_write(struct regmap_field *field, unsigned int id,
 }
 EXPORT_SYMBOL_GPL(regmap_fields_write);
 
+int regmap_fields_force_write(struct regmap_field *field, unsigned int id,
+			unsigned int val)
+{
+	if (id >= field->id_size)
+		return -EINVAL;
+
+	return regmap_write_bits(field->regmap,
+				  field->reg + (field->id_offset * id),
+				  field->mask, val << field->shift);
+}
+EXPORT_SYMBOL_GPL(regmap_fields_force_write);
+
 /**
  * regmap_fields_update_bits():	Perform a read/modify/write cycle
  *                              on the register field
@@ -2327,7 +2339,7 @@ EXPORT_SYMBOL_GPL(regmap_bulk_read);
 
 static int _regmap_update_bits(struct regmap *map, unsigned int reg,
 			       unsigned int mask, unsigned int val,
-			       bool *change)
+			       bool *change, bool force_write)
 {
 	int ret;
 	unsigned int tmp, orig;
@@ -2339,7 +2351,7 @@ static int _regmap_update_bits(struct regmap *map, unsigned int reg,
 	tmp = orig & ~mask;
 	tmp |= val & mask;
 
-	if (tmp != orig) {
+	if (force_write || (tmp != orig)) {
 		ret = _regmap_write(map, reg, tmp);
 		if (change)
 			*change = true;
@@ -2367,7 +2379,7 @@ int regmap_update_bits(struct regmap *map, unsigned int reg,
 	int ret;
 
 	map->lock(map->lock_arg);
-	ret = _regmap_update_bits(map, reg, mask, val, NULL);
+	ret = _regmap_update_bits(map, reg, mask, val, NULL, false);
 	map->unlock(map->lock_arg);
 
 	return ret;
@@ -2375,6 +2387,29 @@ int regmap_update_bits(struct regmap *map, unsigned int reg,
 EXPORT_SYMBOL_GPL(regmap_update_bits);
 
 /**
+ * regmap_write_bits: Perform a read/modify/write cycle on the register map
+ *
+ * @map: Register map to update
+ * @reg: Register to update
+ * @mask: Bitmask to change
+ * @val: New value for bitmask
+ *
+ * Returns zero for success, a negative number on error.
+ */
+int regmap_write_bits(struct regmap *map, unsigned int reg,
+		      unsigned int mask, unsigned int val)
+{
+	int ret;
+
+	map->lock(map->lock_arg);
+	ret = _regmap_update_bits(map, reg, mask, val, NULL, true);
+	map->unlock(map->lock_arg);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regmap_write_bits);
+
+/**
  * regmap_update_bits_async: Perform a read/modify/write cycle on the register
  *                           map asynchronously
  *
@@ -2398,7 +2433,7 @@ int regmap_update_bits_async(struct regmap *map, unsigned int reg,
 
 	map->async = true;
 
-	ret = _regmap_update_bits(map, reg, mask, val, NULL);
+	ret = _regmap_update_bits(map, reg, mask, val, NULL, false);
 
 	map->async = false;
 
@@ -2427,7 +2462,7 @@ int regmap_update_bits_check(struct regmap *map, unsigned int reg,
 	int ret;
 
 	map->lock(map->lock_arg);
-	ret = _regmap_update_bits(map, reg, mask, val, change);
+	ret = _regmap_update_bits(map, reg, mask, val, change, false);
 	map->unlock(map->lock_arg);
 	return ret;
 }
@@ -2460,7 +2495,7 @@ int regmap_update_bits_check_async(struct regmap *map, unsigned int reg,
 
 	map->async = true;
 
-	ret = _regmap_update_bits(map, reg, mask, val, change);
+	ret = _regmap_update_bits(map, reg, mask, val, change, false);
 
 	map->async = false;