UBI: add ubi_sync() interface

To flush MTD device caches.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

2 files changed, 25 insertions, 0 deletions

diff --git a/drivers/mtd/ubi/kapi.c b/drivers/mtd/ubi/kapi.c
index 51508832566d..e65c8e0bcd5d 100644
--- a/drivers/mtd/ubi/kapi.c
+++ b/drivers/mtd/ubi/kapi.c
@@ -632,3 +632,27 @@ int ubi_is_mapped(struct ubi_volume_desc *desc, int lnum)
         return vol->eba_tbl[lnum] >= 0;
 }
 EXPORT_SYMBOL_GPL(ubi_is_mapped);
+
+/**
+ * ubi_sync - synchronize UBI device buffers.
+ * @ubi_num: UBI device to synchronize
+ *
+ * The underlying MTD device may cache data in hardware or in software. This
+ * function ensures the caches are flushed. Returns zero in case of success and
+ * a negative error code in case of failure.
+ */
+int ubi_sync(int ubi_num)
+{
+        struct ubi_device *ubi;
+
+        ubi = ubi_get_device(ubi_num);
+        if (!ubi)
+                return -ENODEV;
+
+        if (ubi->mtd->sync)
+                ubi->mtd->sync(ubi->mtd);
+
+        ubi_put_device(ubi);
+        return 0;
+}
+EXPORT_SYMBOL_GPL(ubi_sync);
diff --git a/include/linux/mtd/ubi.h b/include/linux/mtd/ubi.h
index f71201d0f3e7..83302bbbddb4 100644
--- a/include/linux/mtd/ubi.h
+++ b/include/linux/mtd/ubi.h
@@ -152,6 +152,7 @@ int ubi_leb_erase(struct ubi_volume_desc *desc, int lnum);
 int ubi_leb_unmap(struct ubi_volume_desc *desc, int lnum);
 int ubi_leb_map(struct ubi_volume_desc *desc, int lnum, int dtype);
 int ubi_is_mapped(struct ubi_volume_desc *desc, int lnum);
+int ubi_sync(int ubi_num);
 
 /*
  * This function is the same as the 'ubi_leb_read()' function, but it does not