mtd: introduce mtd_read 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/mtdblock.c b/drivers/mtd/mtdblock.c
index 9b01cb0..b0644d2 100644
--- a/drivers/mtd/mtdblock.c
+++ b/drivers/mtd/mtdblock.c
@@ -184,8 +184,8 @@
 			    mtdblk->cache_offset != sect_start) {
 				/* fill the cache with the current sector */
 				mtdblk->cache_state = STATE_EMPTY;
-				ret = mtd->read(mtd, sect_start, sect_size,
-						&retlen, mtdblk->cache_data);
+				ret = mtd_read(mtd, sect_start, sect_size,
+					       &retlen, mtdblk->cache_data);
 				if (ret)
 					return ret;
 				if (retlen != sect_size)
@@ -222,7 +222,7 @@
 			mtd->name, pos, len);
 
 	if (!sect_size)
-		return mtd->read(mtd, pos, len, &retlen, buf);
+		return mtd_read(mtd, pos, len, &retlen, buf);
 
 	while (len > 0) {
 		unsigned long sect_start = (pos/sect_size)*sect_size;
@@ -241,7 +241,7 @@
 		    mtdblk->cache_offset == sect_start) {
 			memcpy (buf, mtdblk->cache_data + offset, size);
 		} else {
-			ret = mtd->read(mtd, pos, size, &retlen, buf);
+			ret = mtd_read(mtd, pos, size, &retlen, buf);
 			if (ret)
 				return ret;
 			if (retlen != size)