Merge tag 'mtd/for-4.16' of git://git.infradead.org/linux-mtd

[linux-2.6-microblaze.git] / drivers / mtd / mtdcore.c

diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index 73b6055..28553c8 100644 (file)
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -503,6 +503,11 @@ int add_mtd_device(struct mtd_info *mtd)
                return -EEXIST;
 
        BUG_ON(mtd->writesize == 0);
+
+       if (WARN_ON((!mtd->erasesize || !mtd->_erase) &&
+                   !(mtd->flags & MTD_NO_ERASE)))
+               return -EINVAL;
+
        mutex_lock(&mtd_table_mutex);
 
        i = idr_alloc(&mtd_idr, mtd, 0, 0, GFP_KERNEL);
@@ -1053,7 +1058,20 @@ int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
         * representing the maximum number of bitflips that were corrected on
         * any one ecc region (if applicable; zero otherwise).
         */
-       ret_code = mtd->_read(mtd, from, len, retlen, buf);
+       if (mtd->_read) {
+               ret_code = mtd->_read(mtd, from, len, retlen, buf);
+       } else if (mtd->_read_oob) {
+               struct mtd_oob_ops ops = {
+                       .len = len,
+                       .datbuf = buf,
+               };
+
+               ret_code = mtd->_read_oob(mtd, from, &ops);
+               *retlen = ops.retlen;
+       } else {
+               return -ENOTSUPP;
+       }
+
        if (unlikely(ret_code < 0))
                return ret_code;
        if (mtd->ecc_strength == 0)
@@ -1068,11 +1086,25 @@ int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
        *retlen = 0;
        if (to < 0 || to >= mtd->size || len > mtd->size - to)
                return -EINVAL;
-       if (!mtd->_write || !(mtd->flags & MTD_WRITEABLE))
+       if ((!mtd->_write && !mtd->_write_oob) ||
+           !(mtd->flags & MTD_WRITEABLE))
                return -EROFS;
        if (!len)
                return 0;
        ledtrig_mtd_activity();
+
+       if (!mtd->_write) {
+               struct mtd_oob_ops ops = {
+                       .len = len,
+                       .datbuf = (u8 *)buf,
+               };
+               int ret;
+
+               ret = mtd->_write_oob(mtd, to, &ops);
+               *retlen = ops.retlen;
+               return ret;
+       }
+
        return mtd->_write(mtd, to, len, retlen, buf);
 }
 EXPORT_SYMBOL_GPL(mtd_write);