[PATCH v3 7/7] mtd: spinand: esmt: OTP access for F50{L,D}1G41LB

[Martin Kurbanov]

Support for OTP area access on ESMT F50L1G41LB and F50D1G41LB chips.

Signed-off-by: Martin Kurbanov <mmkurbanov at salutedevices.com>
---
 drivers/mtd/nand/spi/esmt.c | 70 +++++++++++++++++++++++++++++++++++--
 1 file changed, 68 insertions(+), 2 deletions(-)

diff --git a/drivers/mtd/nand/spi/esmt.c b/drivers/mtd/nand/spi/esmt.c
index 4597a82de23a4..481005c518f15 100644
--- a/drivers/mtd/nand/spi/esmt.c
+++ b/drivers/mtd/nand/spi/esmt.c
@@ -8,10 +8,15 @@
 #include <linux/device.h>
 #include <linux/kernel.h>
 #include <linux/mtd/spinand.h>
+#include <linux/spi/spi-mem.h>
 
 /* ESMT uses GigaDevice 0xc8 JECDEC ID on some SPI NANDs */
 #define SPINAND_MFR_ESMT_C8			0xc8
 
+#define ESMT_F50L1G41LB_CFG_OTP_PROTECT		BIT(7)
+#define ESMT_F50L1G41LB_CFG_OTP_LOCK		\
+	(CFG_OTP_ENABLE | ESMT_F50L1G41LB_CFG_OTP_PROTECT)
+
 static SPINAND_OP_VARIANTS(read_cache_variants,
 			   SPINAND_PAGE_READ_FROM_CACHE_X4_OP(0, 1, NULL, 0),
 			   SPINAND_PAGE_READ_FROM_CACHE_X2_OP(0, 1, NULL, 0),
@@ -102,6 +107,65 @@ static const struct mtd_ooblayout_ops f50l1g41lb_ooblayout = {
 	.free = f50l1g41lb_ooblayout_free,
 };
 
+static int f50l1g41lb_otp_info(struct spinand_device *spinand, size_t len,
+			       struct otp_info *buf, size_t *retlen)
+{
+	if (len < sizeof(*buf))
+		return -EINVAL;
+
+	buf->locked = 0;
+	buf->start = 0;
+	buf->length = spinand_otp_size(spinand);
+
+	*retlen = sizeof(*buf);
+	return 0;
+}
+
+static int f50l1g41lb_otp_lock(struct spinand_device *spinand, loff_t from,
+			       size_t len)
+{
+	struct spi_mem_op write_op = SPINAND_WR_EN_DIS_OP(true);
+	struct spi_mem_op exec_op = SPINAND_PROG_EXEC_OP(0);
+	u8 status;
+	int ret;
+
+	ret = spinand_upd_cfg(spinand, ESMT_F50L1G41LB_CFG_OTP_LOCK,
+			      ESMT_F50L1G41LB_CFG_OTP_LOCK);
+	if (!ret)
+		return ret;
+
+	ret = spi_mem_exec_op(spinand->spimem, &write_op);
+	if (!ret)
+		goto out;
+
+	ret = spi_mem_exec_op(spinand->spimem, &exec_op);
+	if (!ret)
+		goto out;
+
+	ret = spinand_wait(spinand,
+			   SPINAND_WRITE_INITIAL_DELAY_US,
+			   SPINAND_WRITE_POLL_DELAY_US,
+			   &status);
+	if (!ret && (status & STATUS_PROG_FAILED))
+		ret = -EIO;
+
+out:
+	if (spinand_upd_cfg(spinand, ESMT_F50L1G41LB_CFG_OTP_LOCK, 0)) {
+		dev_warn(&spinand_to_mtd(spinand)->dev,
+			 "Can not disable OTP mode\n");
+		ret = -EIO;
+	}
+
+	return ret;
+}
+
+static const struct spinand_otp_ops f50l1g41lb_otp_ops = {
+	.info = f50l1g41lb_otp_info,
+	.lock = f50l1g41lb_otp_lock,
+	.read = spinand_otp_read,
+	.write = spinand_otp_write,
+};
+
 static const struct spinand_info esmt_c8_spinand_table[] = {
 	SPINAND_INFO("F50L1G41LB",
 		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_ADDR, 0x01, 0x7f,
@@ -112,7 +176,8 @@ static const struct spinand_info esmt_c8_spinand_table[] = {
 					      &write_cache_variants,
 					      &update_cache_variants),
 		     0,
-		     SPINAND_ECCINFO(&f50l1g41lb_ooblayout, NULL)),
+		     SPINAND_ECCINFO(&f50l1g41lb_ooblayout, NULL),
+		     SPINAND_OTP_INFO(28, 2, &f50l1g41lb_otp_ops)),
 	SPINAND_INFO("F50D1G41LB",
 		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_ADDR, 0x11, 0x7f,
 				0x7f, 0x7f),
@@ -122,7 +187,8 @@ static const struct spinand_info esmt_c8_spinand_table[] = {
 					      &write_cache_variants,
 					      &update_cache_variants),
 		     0,
-		     SPINAND_ECCINFO(&f50l1g41lb_ooblayout, NULL)),
+		     SPINAND_ECCINFO(&f50l1g41lb_ooblayout, NULL),
+		     SPINAND_OTP_INFO(28, 2, &f50l1g41lb_otp_ops)),
 	SPINAND_INFO("F50D2G41KA",
 		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_ADDR, 0x51, 0x7f,
 				0x7f, 0x7f),
-- 
2.43.0