[PATCH] mtd: rawnand: Ensure ECC configuration is propagated to upper layers

[Sascha Hauer <s.hauer@pengutronix.de>]

This is an adoption of Linux Commit:

|commit 3a1b777eb9fb75d09c45ae5dd1d007eddcbebf1f
|Author: Miquel Raynal <miquel.raynal@bootlin.com>
|Date:   Tue May 7 10:58:42 2024 +0200
|
|    mtd: rawnand: Ensure ECC configuration is propagated to upper layers
|
|    Until recently the "upper layer" was MTD. But following incremental
|    reworks to bring spi-nand support and more recently generic ECC support,
|    there is now an intermediate "generic NAND" layer that also needs to get
|    access to some values. When using "converted" ECC engines, like the
|    software ones, these values are already propagated correctly. But
|    otherwise when using good old raw NAND controller drivers, we need to
|    manually set these values ourselves at the end of the "scan" operation,
|    once these values have been negotiated.
|
|    Without this propagation, later (generic) checks like the one warning
|    users that the ECC strength is not high enough might simply no longer
|    work.
|
|    Fixes: 8c126720fe10 ("mtd: rawnand: Use the ECC framework nand_ecc_is_strong_enough() helper")
|    Cc: stable@vger.kernel.org
|    Reported-by: Sascha Hauer <s.hauer@pengutronix.de>
|    Closes: https://lore.kernel.org/all/Zhe2JtvvN1M4Ompw@pengutronix.de/
|    Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
|    Tested-by: Sascha Hauer <s.hauer@pengutronix.de>
|    Link: https://lore.kernel.org/linux-mtd/20240507085842.108844-1-miquel.raynal@bootlin.com

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 drivers/mtd/nand/raw/nand_base.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c
index e586c4cc89..b6bef46499 100644
--- a/drivers/mtd/nand/raw/nand_base.c
+++ b/drivers/mtd/nand/raw/nand_base.c
@@ -6087,6 +6087,7 @@ static const struct nand_ops rawnand_ops = {
 int nand_scan_tail(struct nand_chip *chip)
 {
 	struct mtd_info *mtd = nand_to_mtd(chip);
+	struct nand_device *base = &chip->base;
 	struct nand_ecc_ctrl *ecc = &chip->ecc;
 	int ret, i;
 
@@ -6231,9 +6232,13 @@ int nand_scan_tail(struct nand_chip *chip)
 	if (!ecc->write_oob_raw)
 		ecc->write_oob_raw = ecc->write_oob;
 
-	/* propagate ecc info to mtd_info */
+	/* Propagate ECC info to the generic NAND and MTD layers */
 	mtd->ecc_strength = ecc->strength;
+	if (!base->ecc.ctx.conf.strength)
+		base->ecc.ctx.conf.strength = ecc->strength;
 	mtd->ecc_step_size = ecc->size;
+	if (!base->ecc.ctx.conf.step_size)
+		base->ecc.ctx.conf.step_size = ecc->size;
 
 	/*
 	 * Set the number of read / write steps for one page depending on ECC
@@ -6241,6 +6246,8 @@ int nand_scan_tail(struct nand_chip *chip)
 	 */
 	if (!ecc->steps)
 		ecc->steps = mtd->writesize / ecc->size;
+	if (!base->ecc.ctx.nsteps)
+		base->ecc.ctx.nsteps = ecc->steps;
 	if (ecc->steps * ecc->size != mtd->writesize) {
 		WARN(1, "Invalid ECC parameters\n");
 		ret = -EINVAL;
-- 
2.39.2