[PATCH 3/4] mtd: rawnand: Prevent sequential reads with on-die ECC engines

[Miquel Raynal]

Some devices support sequential reads when using the on-die ECC engines,
some others do not. It is a bit hard to know which ones will break other
than experimentally, so in order to avoid such a difficult and painful
task, let's just pretend all devices should avoid using this
optimization when configured like this.

Cc: stable at vger.kernel.org
Fixes: 003fe4b9545b ("mtd: rawnand: Support for sequential cache reads")
Signed-off-by: Miquel Raynal <miquel.raynal at bootlin.com>
---
 drivers/mtd/nand/raw/nand_base.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c
index 1b0a984d181d..139fdf3e58c0 100644
--- a/drivers/mtd/nand/raw/nand_base.c
+++ b/drivers/mtd/nand/raw/nand_base.c
@@ -5170,6 +5170,14 @@ static void rawnand_late_check_supported_ops(struct nand_chip *chip)
 	/* The supported_op fields should not be set by individual drivers */
 	WARN_ON_ONCE(chip->controller->supported_op.cont_read);
 
+	/*
+	 * Too many devices do not support sequential cached reads with on-die
+	 * ECC correction enabled, so in this case refuse to perform the
+	 * automation.
+	 */
+	if (chip->ecc.engine_type == NAND_ECC_ENGINE_TYPE_ON_DIE)
+		return;
+
 	if (!nand_has_exec_op(chip))
 		return;
 
-- 
2.34.1