[PATCH v4 3/5] mtd: rawnand: meson: always read whole OOB bytes

[Arseniy Krasnov <AVKrasnov@sberdevices.ru>]

This changes size of read access to OOB area by reading all bytes of
OOB (free bytes + ECC engine bytes).

Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru>
---
 drivers/mtd/nand/raw/meson_nand.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/drivers/mtd/nand/raw/meson_nand.c b/drivers/mtd/nand/raw/meson_nand.c
index 8526a6b87720..a31106c943d7 100644
--- a/drivers/mtd/nand/raw/meson_nand.c
+++ b/drivers/mtd/nand/raw/meson_nand.c
@@ -755,6 +755,30 @@ static int __meson_nfc_read_oob(struct nand_chip *nand, int page,
 	u32 oob_bytes;
 	u32 page_size;
 	int ret;
+	int i;
+
+	/* Read ECC codes and user bytes. */
+	for (i = 0; i < nand->ecc.steps; i++) {
+		u32 ecc_offs = nand->ecc.size * (i + 1) +
+			       NFC_OOB_PER_ECC(nand) * i;
+
+		ret = nand_read_page_op(nand, page, 0, NULL, 0);
+		if (ret)
+			return ret;
+
+		/* Use temporary buffer, because 'nand_change_read_column_op()'
+		 * seems work with some alignment, so we can't read data to
+		 * 'oob_buf' directly.
+		 */
+		ret = nand_change_read_column_op(nand, ecc_offs, meson_chip->oob_buf,
+						 NFC_OOB_PER_ECC(nand), false);
+		if (ret)
+			return ret;
+
+		memcpy(oob_buf + i * NFC_OOB_PER_ECC(nand),
+		       meson_chip->oob_buf,
+		       NFC_OOB_PER_ECC(nand));
+	}
 
 	oob_bytes = meson_nfc_get_oob_bytes(nand);
 
-- 
2.35.0