From f6dffe2a9ed1bdcee1879e2728310fb1e08602cf Mon Sep 17 00:00:00 2001
From: Mikhail Zhilkin <csharper2005@gmail.com>
Date: Thu, 27 Nov 2025 22:59:00 +0300
Subject: mtd: spinand: add support for FudanMicro FM25S01BI3

Add support for FudanMicro FM25S01BI3 SPI NAND.

Link: https://www.fmsh.com/nvm/FM25S01BI3_ds_eng.pdf

Signed-off-by: Mikhail Zhilkin <csharper2005@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 drivers/mtd/nand/spi/fmsh.c | 72 +++++++++++++++++++++++++++++++++++++
 1 file changed, 72 insertions(+)

--- a/drivers/mtd/nand/spi/fmsh.c
+++ b/drivers/mtd/nand/spi/fmsh.c
@@ -9,6 +9,13 @@
 #include <linux/kernel.h>
 #include <linux/mtd/spinand.h>
 
+#define FM25S01BI3_STATUS_ECC_MASK		(7 << 4)
+	#define FM25S01BI3_STATUS_ECC_NO_BITFLIPS	(0 << 4)
+	#define FM25S01BI3_STATUS_ECC_1_3_BITFLIPS	(1 << 4)
+	#define FM25S01BI3_STATUS_ECC_UNCOR_ERROR	(2 << 4)
+	#define FM25S01BI3_STATUS_ECC_4_6_BITFLIPS	(3 << 4)
+	#define FM25S01BI3_STATUS_ECC_7_8_BITFLIPS	(5 << 4)
+
 #define SPINAND_MFR_FMSH		0xA1
 
 static SPINAND_OP_VARIANTS(read_cache_variants,
@@ -45,11 +52,66 @@ static int fm25s01a_ooblayout_free(struc
 	return 0;
 }
 
+static int fm25s01bi3_ecc_get_status(struct spinand_device *spinand,
+				     u8 status)
+{
+	switch (status & FM25S01BI3_STATUS_ECC_MASK) {
+	case FM25S01BI3_STATUS_ECC_NO_BITFLIPS:
+		return 0;
+
+	case FM25S01BI3_STATUS_ECC_UNCOR_ERROR:
+		return -EBADMSG;
+
+	case FM25S01BI3_STATUS_ECC_1_3_BITFLIPS:
+		return 3;
+
+	case FM25S01BI3_STATUS_ECC_4_6_BITFLIPS:
+		return 6;
+
+	case FM25S01BI3_STATUS_ECC_7_8_BITFLIPS:
+		return 8;
+
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static int fm25s01bi3_ooblayout_ecc(struct mtd_info *mtd, int section,
+				    struct mtd_oob_region *region)
+{
+	if (section)
+		return -ERANGE;
+
+	region->offset = 64;
+	region->length = 64;
+
+	return 0;
+}
+
+static int fm25s01bi3_ooblayout_free(struct mtd_info *mtd, int section,
+				     struct mtd_oob_region *region)
+{
+	if (section > 3)
+		return -ERANGE;
+
+	region->offset = (16 * section) + 4;
+	region->length = 12;
+
+	return 0;
+}
+
 static const struct mtd_ooblayout_ops fm25s01a_ooblayout = {
 	.ecc = fm25s01a_ooblayout_ecc,
 	.free = fm25s01a_ooblayout_free,
 };
 
+static const struct mtd_ooblayout_ops fm25s01bi3_ooblayout = {
+	.ecc = fm25s01bi3_ooblayout_ecc,
+	.free = fm25s01bi3_ooblayout_free,
+};
+
 static const struct spinand_info fmsh_spinand_table[] = {
 	SPINAND_INFO("FM25S01A",
 		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xE4),
@@ -60,6 +122,16 @@ static const struct spinand_info fmsh_sp
 					      &update_cache_variants),
 		     0,
 		     SPINAND_ECCINFO(&fm25s01a_ooblayout, NULL)),
+	SPINAND_INFO("FM25S01BI3",
+		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xd4),
+		     NAND_MEMORG(1, 2048, 128, 64, 1024, 20, 1, 1, 1),
+		     NAND_ECCREQ(8, 512),
+		     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
+					      &write_cache_variants,
+					      &update_cache_variants),
+		     SPINAND_HAS_QE_BIT,
+		     SPINAND_ECCINFO(&fm25s01bi3_ooblayout,
+				      fm25s01bi3_ecc_get_status)),
 };
 
 static const struct spinand_manufacturer_ops fmsh_spinand_manuf_ops = {
