mtd: add the support to parse out the full-id nand type

When we meet a full-id nand type whose @id_len is not zero, we can use
the find_full_id_nand() to parse out the necessary information for a
nand chip.

If we meet a non full-id nand type, we can handle it in the legacy way.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Reviewed-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/nand/nand_base.c

@@ -3087,6 +3087,30 @@ static void nand_decode_bbm_options(struct mtd_info *mtd,
 		chip->bbt_options |= NAND_BBT_SCAN2NDPAGE;
 }
 
+static inline bool is_full_id_nand(struct nand_flash_dev *type)
+{
+	return type->id_len;
+}
+
+static bool find_full_id_nand(struct mtd_info *mtd, struct nand_chip *chip,
+		   struct nand_flash_dev *type, u8 *id_data, int *busw)
+{
+	if (!strncmp(type->id, id_data, type->id_len)) {
+		mtd->writesize = type->pagesize;
+		mtd->erasesize = type->erasesize;
+		mtd->oobsize = type->oobsize;
+
+		chip->cellinfo = id_data[2];
+		chip->chipsize = (uint64_t)type->chipsize << 20;
+		chip->options |= type->options;
+
+		*busw = type->options & NAND_BUSWIDTH_16;
+
+		return true;
+	}
+	return false;
+}
+
 /*
  * Get the flash and manufacturer id and lookup if the type is supported.
  */
@@ -3138,9 +3162,14 @@ static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd,
 	if (!type)
 		type = nand_flash_ids;
 
-	for (; type->name != NULL; type++)
-		if (*dev_id == type->dev_id)
-			break;
+	for (; type->name != NULL; type++) {
+		if (is_full_id_nand(type)) {
+			if (find_full_id_nand(mtd, chip, type, id_data, &busw))
+				goto ident_done;
+		} else if (*dev_id == type->dev_id) {
+				break;
+		}
+	}
 
 	chip->onfi_version = 0;
 	if (!type->name || !type->pagesize) {