mtd: rawnand: diskonchip: Move the ECC initialization to ->attach_chip()

The probe function is only supposed to initialize the controller
hardware but not the ECC engine. Indeed, we don't know anything about
the NAND chip(s) at this stage. Let's move the logic initializing the
ECC engine, even pretty simple, to the ->attach_chip() hook which gets
called during nand_scan() routine, after the NAND chip discovery. As
the previously mentioned logic is supposed to parse the DT for us, it
is likely that the chip->ecc.* entries be overwritten. So let's avoid
this by moving these lines to ->attach_chip().

Fixes: d7157ff4 ("mtd: rawnand: Use the ECC framework user input parsing bits")
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20201113123424.32233-8-miquel.raynal@bootlin.com

drivers/mtd/nand/raw/diskonchip.c

@@ -1269,12 +1269,31 @@ static inline int __init doc2001plus_init(struct mtd_info *mtd)
 	return 1;
 }
 
+static int doc200x_attach_chip(struct nand_chip *chip)
+{
+	if (chip->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST)
+		return 0;
+
+	chip->ecc.placement = NAND_ECC_PLACEMENT_INTERLEAVED;
+	chip->ecc.size = 512;
+	chip->ecc.bytes = 6;
+	chip->ecc.strength = 2;
+	chip->ecc.options = NAND_ECC_GENERIC_ERASED_CHECK;
+	chip->ecc.hwctl = doc200x_enable_hwecc;
+	chip->ecc.calculate = doc200x_calculate_ecc;
+	chip->ecc.correct = doc200x_correct_data;
+
+	return 0;
+}
+
 static const struct nand_controller_ops doc200x_ops = {
 	.exec_op = doc200x_exec_op,
+	.attach_chip = doc200x_attach_chip,
 };
 
 static const struct nand_controller_ops doc2001plus_ops = {
 	.exec_op = doc2001plus_exec_op,
+	.attach_chip = doc200x_attach_chip,
 };
 
 static int __init doc_probe(unsigned long physadr)
@@ -1452,16 +1471,6 @@ static int __init doc_probe(unsigned long physadr)
 
 	nand->controller	= &doc->base;
 	nand_set_controller_data(nand, doc);
-	nand->ecc.hwctl		= doc200x_enable_hwecc;
-	nand->ecc.calculate	= doc200x_calculate_ecc;
-	nand->ecc.correct	= doc200x_correct_data;
-
-	nand->ecc.engine_type	= NAND_ECC_ENGINE_TYPE_ON_HOST;
-	nand->ecc.placement	= NAND_ECC_PLACEMENT_INTERLEAVED;
-	nand->ecc.size		= 512;
-	nand->ecc.bytes		= 6;
-	nand->ecc.strength	= 2;
-	nand->ecc.options	= NAND_ECC_GENERIC_ERASED_CHECK;
 	nand->bbt_options	= NAND_BBT_USE_FLASH;
 	/* Skip the automatic BBT scan so we can run it manually */
 	nand->options		|= NAND_SKIP_BBTSCAN | NAND_NO_BBM_QUIRK;