[PATCH V3 1/2] mtd: move code adding master MTD out of mtd_add_device_partitions

["Rafał Miłecki" <zajec5@gmail.com>]

From: Rafał Miłecki <rafal@milecki.pl>

This change is a small cleanup of mtd_device_parse_register. When using
MTD_PARTITIONED_MASTER it makes sure a master MTD is registered before
dealing with partitions. There are 2 advantages of this:
1) Not mixing code handling master MTD with code handling partitions
2) Possibility of reusing mtd_parse_part in the future to avoid some
   code duplication.

This commit doesn't change any behavior except from a slightly different
failure code path. The new code may need to call del_mtd_device when
something goes wrong.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
V2: Use device_is_registered (thanks Boris)
    Add an empty line before "return ret;"
V3: Use device_is_registered also in a out code path
---
 drivers/mtd/mtdcore.c | 25 +++++++++++++------------
 1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index f80e911b8843..3304199cca07 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -641,20 +641,12 @@ static int mtd_add_device_partitions(struct mtd_info *mtd,
 {
 	const struct mtd_partition *real_parts = parts->parts;
 	int nbparts = parts->nr_parts;
-	int ret;
 
-	if (nbparts == 0 || IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER)) {
-		ret = add_mtd_device(mtd);
-		if (ret)
-			return ret;
-	}
+	if (!nbparts && !device_is_registered(&mtd->dev))
+		return add_mtd_device(mtd);
 
-	if (nbparts > 0) {
-		ret = add_mtd_partitions(mtd, real_parts, nbparts);
-		if (ret && IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER))
-			del_mtd_device(mtd);
-		return ret;
-	}
+	if (nbparts > 0)
+		return add_mtd_partitions(mtd, real_parts, nbparts);
 
 	return 0;
 }
@@ -714,6 +706,12 @@ int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types,
 
 	mtd_set_dev_defaults(mtd);
 
+	if (IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER)) {
+		ret = add_mtd_device(mtd);
+		if (ret)
+			return ret;
+	}
+
 	memset(&parsed, 0, sizeof(parsed));
 
 	ret = parse_mtd_partitions(mtd, types, &parsed, parser_data);
@@ -753,6 +751,9 @@ int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types,
 out:
 	/* Cleanup any parsed partitions */
 	mtd_part_parser_cleanup(&parsed);
+	if (ret && device_is_registered(&mtd->dev))
+		del_mtd_device(mtd);
+
 	return ret;
 }
 EXPORT_SYMBOL_GPL(mtd_device_parse_register);
-- 
2.11.0