21.02/files/target/linux/generic/backport-5.4/999-2321-mtd-spinand-micron-identify-SPI-NAND-device-with-Continuous-Read-mode.patch

From 65c3b878a33bb7edd5413860537fecdff94aaba6 Mon Sep 17 00:00:00 2001
From: Sam Shih <sam.shih@mediatek.com>
Date: Fri, 2 Jun 2023 13:06:12 +0800
Subject: [PATCH] 
 [spi-and-storage][999-2321-mtd-spinand-micron-identify-SPI-NAND-device-with-Continuous-Read-mode.patch]

---
 drivers/mtd/nand/spi/micron.c | 16 ++++++++++++++++
 include/linux/mtd/spinand.h   |  1 +
 2 files changed, 17 insertions(+)

diff --git a/drivers/mtd/nand/spi/micron.c b/drivers/mtd/nand/spi/micron.c
index 26925714a..956f7710a 100644
--- a/drivers/mtd/nand/spi/micron.c
+++ b/drivers/mtd/nand/spi/micron.c
@@ -18,6 +18,8 @@
 #define MICRON_STATUS_ECC_4TO6_BITFLIPS	(3 << 4)
 #define MICRON_STATUS_ECC_7TO8_BITFLIPS	(5 << 4)
 
+#define MICRON_CFG_CR			BIT(0)
+
 static SPINAND_OP_VARIANTS(read_cache_variants,
 		SPINAND_PAGE_READ_FROM_CACHE_QUADIO_OP(0, 2, NULL, 0),
 		SPINAND_PAGE_READ_FROM_CACHE_X4_OP(0, 1, NULL, 0),
@@ -137,7 +139,21 @@ static const struct spinand_info micron_spinand_table[] = {
 				     micron_8_ecc_get_status)),
 };
 
+static int micron_spinand_init(struct spinand_device *spinand)
+{
+	/*
+	 * M70A device series enable Continuous Read feature at Power-up,
+	 * which is not supported. Disable this bit to avoid any possible
+	 * failure.
+	 */
+	if (spinand->flags & SPINAND_HAS_CR_FEAT_BIT)
+		return spinand_upd_cfg(spinand, MICRON_CFG_CR, 0);
+
+	return 0;
+}
+
 static const struct spinand_manufacturer_ops micron_spinand_manuf_ops = {
+	.init = micron_spinand_init,
 };
 
 const struct spinand_manufacturer micron_spinand_manufacturer = {
diff --git a/include/linux/mtd/spinand.h b/include/linux/mtd/spinand.h
index f4c4ae871..1077c4572 100644
--- a/include/linux/mtd/spinand.h
+++ b/include/linux/mtd/spinand.h
@@ -284,6 +284,7 @@ struct spinand_ecc_info {
 };
 
 #define SPINAND_HAS_QE_BIT		BIT(0)
+#define SPINAND_HAS_CR_FEAT_BIT		BIT(1)
 
 /**
  * struct spinand_info - Structure used to describe SPI NAND chips
-- 
2.34.1