mtd: introduce mtd_sync interface

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/ftl.c b/drivers/mtd/ftl.c
index d591b1d..c9c9029 100644
--- a/drivers/mtd/ftl.c
+++ b/drivers/mtd/ftl.c
@@ -651,7 +651,7 @@
 		pr_debug("ftl_cs: waiting for transfer "
 		      "unit to be prepared...\n");
 		if (part->mbd.mtd->sync)
-			part->mbd.mtd->sync(part->mbd.mtd);
+			mtd_sync(part->mbd.mtd);
 	    } else {
 		static int ne = 0;
 		if (++ne < 5)
diff --git a/drivers/mtd/mtdblock.c b/drivers/mtd/mtdblock.c
index ac7f1f1..496e1a6 100644
--- a/drivers/mtd/mtdblock.c
+++ b/drivers/mtd/mtdblock.c
@@ -323,7 +323,7 @@
 	if (!--mtdblk->count) {
 		/* It was the last usage. Free the cache */
 		if (mbd->mtd->sync)
-			mbd->mtd->sync(mbd->mtd);
+			mtd_sync(mbd->mtd);
 		vfree(mtdblk->cache_data);
 	}
 
@@ -343,7 +343,7 @@
 	mutex_unlock(&mtdblk->cache_mutex);
 
 	if (dev->mtd->sync)
-		dev->mtd->sync(dev->mtd);
+		mtd_sync(dev->mtd);
 	return 0;
 }
 
diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
index 86308ac..b5722ec 100644
--- a/drivers/mtd/mtdchar.c
+++ b/drivers/mtd/mtdchar.c
@@ -155,7 +155,7 @@
 
 	/* Only sync if opened RW */
 	if ((file->f_mode & FMODE_WRITE) && mtd->sync)
-		mtd->sync(mtd);
+		mtd_sync(mtd);
 
 	iput(mfi->ino);
 
diff --git a/drivers/mtd/mtdconcat.c b/drivers/mtd/mtdconcat.c
index 6fdae19..cc2336e 100644
--- a/drivers/mtd/mtdconcat.c
+++ b/drivers/mtd/mtdconcat.c
@@ -620,7 +620,7 @@
 
 	for (i = 0; i < concat->num_subdev; i++) {
 		struct mtd_info *subdev = concat->subdev[i];
-		subdev->sync(subdev);
+		mtd_sync(subdev);
 	}
 }
 
diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
index c0bfa88..2b54505 100644
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -301,7 +301,7 @@
 static void part_sync(struct mtd_info *mtd)
 {
 	struct mtd_part *part = PART(mtd);
-	part->master->sync(part->master);
+	mtd_sync(part->master);
 }
 
 static int part_suspend(struct mtd_info *mtd)
diff --git a/drivers/mtd/mtdswap.c b/drivers/mtd/mtdswap.c
index 8579739..cb794e7 100644
--- a/drivers/mtd/mtdswap.c
+++ b/drivers/mtd/mtdswap.c
@@ -1048,7 +1048,7 @@
 	struct mtdswap_dev *d = MTDSWAP_MBD_TO_MTDSWAP(dev);
 
 	if (d->mtd->sync)
-		d->mtd->sync(d->mtd);
+		mtd_sync(d->mtd);
 	return 0;
 }
 
diff --git a/drivers/mtd/rfd_ftl.c b/drivers/mtd/rfd_ftl.c
index c594bb7..5426d42 100644
--- a/drivers/mtd/rfd_ftl.c
+++ b/drivers/mtd/rfd_ftl.c
@@ -449,7 +449,7 @@
 
 	/* we have a race if sync doesn't exist */
 	if (part->mbd.mtd->sync)
-		part->mbd.mtd->sync(part->mbd.mtd);
+		mtd_sync(part->mbd.mtd);
 
 	score = 0x7fffffff; /* MAX_INT */
 	best_block = -1;
diff --git a/drivers/mtd/ubi/kapi.c b/drivers/mtd/ubi/kapi.c
index 1a35fc5..9f265cc 100644
--- a/drivers/mtd/ubi/kapi.c
+++ b/drivers/mtd/ubi/kapi.c
@@ -715,7 +715,7 @@
 		return -ENODEV;
 
 	if (ubi->mtd->sync)
-		ubi->mtd->sync(ubi->mtd);
+		mtd_sync(ubi->mtd);
 
 	ubi_put_device(ubi);
 	return 0;