[PATCH v2 5/9] mtd: rawnand: jz4780: Add ooblayout for the JZ4725B

[Paul Cercueil]

The boot ROM of the JZ4725B SoC expects a specific OOB layout on the
NAND.

Add an optional "ingenic,oob-layout" device property. When set to
"ingenic,jz4725b", this specific OOB layout is used.

Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
---

Changes:

v2: Instead of forcing the OOB layout, leave it to the board code or
    devicetree to decide if the jz4725b-specific layout should be used
    or not.

 drivers/mtd/nand/raw/ingenic/jz4780_nand.c | 51 +++++++++++++++++++++-
 1 file changed, 50 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/nand/raw/ingenic/jz4780_nand.c b/drivers/mtd/nand/raw/ingenic/jz4780_nand.c
index c0855fef7735..baebb9a5c7c8 100644
--- a/drivers/mtd/nand/raw/ingenic/jz4780_nand.c
+++ b/drivers/mtd/nand/raw/ingenic/jz4780_nand.c
@@ -44,6 +44,7 @@ struct jz4780_nand_cs {
 struct jz4780_nand_controller {
 	struct device *dev;
 	const struct jz_soc_info *soc_info;
+	const struct mtd_ooblayout_ops *oob_layout;
 	struct jz4780_bch *bch;
 	struct nand_controller controller;
 	unsigned int num_banks;
@@ -213,7 +214,7 @@ static int jz4780_nand_attach_chip(struct nand_chip *chip)
 		return -EINVAL;
 	}
 
-	mtd_set_ooblayout(mtd, &nand_ooblayout_lp_ops);
+	mtd_set_ooblayout(mtd, nfc->oob_layout);
 
 	return 0;
 }
@@ -345,11 +346,47 @@ static int jz4780_nand_init_chips(struct jz4780_nand_controller *nfc,
 	return 0;
 }
 
+static int jz4725b_ooblayout_ecc(struct mtd_info *mtd, int section,
+				 struct mtd_oob_region *oobregion)
+{
+	struct nand_chip *chip = mtd_to_nand(mtd);
+	struct nand_ecc_ctrl *ecc = &chip->ecc;
+
+	if (section || !ecc->total)
+		return -ERANGE;
+
+	oobregion->length = ecc->total;
+	oobregion->offset = 3;
+
+	return 0;
+}
+
+static int jz4725b_ooblayout_free(struct mtd_info *mtd, int section,
+				  struct mtd_oob_region *oobregion)
+{
+	struct nand_chip *chip = mtd_to_nand(mtd);
+	struct nand_ecc_ctrl *ecc = &chip->ecc;
+
+	if (section)
+		return -ERANGE;
+
+	oobregion->length = mtd->oobsize - ecc->total - 3;
+	oobregion->offset = 3 + ecc->total;
+
+	return 0;
+}
+
+const struct mtd_ooblayout_ops jz4725b_ooblayout_ops = {
+	.ecc = jz4725b_ooblayout_ecc,
+	.free = jz4725b_ooblayout_free,
+};
+
 static int jz4780_nand_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	unsigned int num_banks;
 	struct jz4780_nand_controller *nfc;
+	const char *layout;
 	int ret;
 
 	num_banks = jz4780_nemc_num_banks(dev);
@@ -366,6 +403,18 @@ static int jz4780_nand_probe(struct platform_device *pdev)
 	if (!nfc->soc_info)
 		return -EINVAL;
 
+	nfc->oob_layout = &nand_ooblayout_lp_ops;
+
+	ret = device_property_read_string(dev, "ingenic,oob-layout", &layout);
+	if (!ret) {
+		if (!strcmp(layout, "ingenic,jz4725b")) {
+			nfc->oob_layout  = &jz4725b_ooblayout_ops;
+		} else {
+			dev_err(dev, "Unrecognized OOB layout %s\n", layout);
+			return -EINVAL;
+		}
+	}
+
 	/*
 	 * Check for BCH HW before we call nand_scan_ident, to prevent us from
 	 * having to call it again if the BCH driver returns -EPROBE_DEFER.
-- 
2.20.1