FAILED: patch "[PATCH] mtd: spinand: Fix MTD_OPS_AUTO_OOB requests" failed to apply to 5.4-stable tree

[<gregkh@xxxxxxxxxxxxxxxxxxx>]

The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

>From e708789c4a87989faff1131ccfdc465a1c1eddbc Mon Sep 17 00:00:00 2001
From: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
Date: Thu, 7 Jan 2021 09:38:13 +0100
Subject: [PATCH] mtd: spinand: Fix MTD_OPS_AUTO_OOB requests

The initial change breaking the logic is
commit 3d1f08b032dc ("mtd: spinand: Use the external ECC engine logic")
It inadvertently dropped proper OOB support while doing something
else.

Shortly later, half of it got re-integrated by
commit 868cbe2a6dce ("mtd: spinand: Fix OOB read")
(pointing by the way to a  more early change which had nothing to do
with the issue). Problem is, this commit failed to revert the faulty
change entirely and missed the logic handling MTD_OPS_AUTO_OOB
requests.

Let's fix this mess by re-inserting the missing part now.

Fixes: 868cbe2a6dce ("mtd: spinand: Fix OOB read")
Reported-by: Felix Fietkau <nbd@xxxxxxxx>
Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
Link: https://lore.kernel.org/linux-mtd/20210107083813.24283-1-miquel.raynal@xxxxxxxxxxx

diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c
index 8ea545bb924d..61d932c1b718 100644
--- a/drivers/mtd/nand/spi/core.c
+++ b/drivers/mtd/nand/spi/core.c
@@ -343,6 +343,7 @@ static int spinand_read_from_cache_op(struct spinand_device *spinand,
 				      const struct nand_page_io_req *req)
 {
 	struct nand_device *nand = spinand_to_nand(spinand);
+	struct mtd_info *mtd = spinand_to_mtd(spinand);
 	struct spi_mem_dirmap_desc *rdesc;
 	unsigned int nbytes = 0;
 	void *buf = NULL;
@@ -382,9 +383,16 @@ static int spinand_read_from_cache_op(struct spinand_device *spinand,
 		memcpy(req->databuf.in, spinand->databuf + req->dataoffs,
 		       req->datalen);
 
-	if (req->ooblen)
-		memcpy(req->oobbuf.in, spinand->oobbuf + req->ooboffs,
-		       req->ooblen);
+	if (req->ooblen) {
+		if (req->mode == MTD_OPS_AUTO_OOB)
+			mtd_ooblayout_get_databytes(mtd, req->oobbuf.in,
+						    spinand->oobbuf,
+						    req->ooboffs,
+						    req->ooblen);
+		else
+			memcpy(req->oobbuf.in, spinand->oobbuf + req->ooboffs,
+			       req->ooblen);
+	}
 
 	return 0;
 }