[PATCH v5 2/3] mtd: spi-nand: Add support for randomizer

[Cheng Ming Lin <linchengming884@gmail.com>]

From: Cheng Ming Lin <chengminglin@mxic.com.tw>

This patch adds support for the randomizer feature.

It introduces a 'set_randomizer' callback in 'struct spinand_info' and
'struct spinand_device'.

If a driver implements this callback, the core will invoke it during
device initialization (spinand_init) to enable or disable the randomizer
feature based on the device tree configuration.

Signed-off-by: Cheng Ming Lin <chengminglin@mxic.com.tw>
---
 drivers/mtd/nand/spi/core.c | 27 +++++++++++++++++++++++++++
 include/linux/mtd/spinand.h |  9 +++++++++
 2 files changed, 36 insertions(+)

diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c
index d207286572d8..d6b12d05c346 100644
--- a/drivers/mtd/nand/spi/core.c
+++ b/drivers/mtd/nand/spi/core.c
@@ -1218,6 +1218,29 @@ static int spinand_create_dirmaps(struct spinand_device *spinand)
 	return 0;
 }
 
+static int spinand_randomizer_init(struct spinand_device *spinand)
+{
+	struct device_node *np = spinand->spimem->spi->dev.of_node;
+	bool enable = false;
+	int ret;
+
+	if (!spinand->set_randomizer)
+		return 0;
+
+	if (of_property_read_bool(np, "nand-enable-randomizer"))
+		enable = true;
+	else if (of_property_read_bool(np, "nand-disable-randomizer"))
+		enable = false;
+	else
+		return 0;
+
+	ret = spinand->set_randomizer(spinand, enable);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
 static const struct nand_ops spinand_ops = {
 	.erase = spinand_erase,
 	.markbad = spinand_markbad,
@@ -1412,6 +1435,7 @@ int spinand_match_and_init(struct spinand_device *spinand,
 		spinand->user_otp = &table[i].user_otp;
 		spinand->read_retries = table[i].read_retries;
 		spinand->set_read_retry = table[i].set_read_retry;
+		spinand->set_randomizer = table[i].set_randomizer;
 
 		op = spinand_select_op_variant(spinand,
 					       info->op_variants.read_cache);
@@ -1588,6 +1612,9 @@ static int spinand_init(struct spinand_device *spinand)
 	 * ECC initialization must have happened previously.
 	 */
 	spinand_cont_read_init(spinand);
+	ret = spinand_randomizer_init(spinand);
+	if (ret)
+		goto err_cleanup_nanddev;
 
 	mtd->_read_oob = spinand_mtd_read;
 	mtd->_write_oob = spinand_mtd_write;
diff --git a/include/linux/mtd/spinand.h b/include/linux/mtd/spinand.h
index ce76f5c632e1..e01315a71222 100644
--- a/include/linux/mtd/spinand.h
+++ b/include/linux/mtd/spinand.h
@@ -501,6 +501,7 @@ struct spinand_user_otp {
  * @user_otp: SPI NAND user OTP info.
  * @read_retries: the number of read retry modes supported
  * @set_read_retry: enable/disable read retry for data recovery
+ * @set_randomizer: enable/disable randomizer support
  *
  * Each SPI NAND manufacturer driver should have a spinand_info table
  * describing all the chips supported by the driver.
@@ -527,6 +528,8 @@ struct spinand_info {
 	unsigned int read_retries;
 	int (*set_read_retry)(struct spinand_device *spinand,
 			     unsigned int read_retry);
+	int (*set_randomizer)(struct spinand_device *spinand,
+			      bool enable);
 };
 
 #define SPINAND_ID(__method, ...)					\
@@ -580,6 +583,9 @@ struct spinand_info {
 	.read_retries = __read_retries,					\
 	.set_read_retry = __set_read_retry
 
+#define SPINAND_RANDOMIZER(__set_randomizer)				\
+	.set_randomizer = __set_randomizer
+
 #define SPINAND_INFO(__model, __id, __memorg, __eccreq, __op_variants,	\
 		     __flags, ...)					\
 	{								\
@@ -635,6 +641,7 @@ struct spinand_dirmap {
  * @user_otp: SPI NAND user OTP info.
  * @read_retries: the number of read retry modes supported
  * @set_read_retry: Enable/disable the read retry feature
+ * @set_randomizer: Enable/disable the randomizer feature
  */
 struct spinand_device {
 	struct nand_device base;
@@ -668,6 +675,8 @@ struct spinand_device {
 	bool cont_read_possible;
 	int (*set_cont_read)(struct spinand_device *spinand,
 			     bool enable);
+	int (*set_randomizer)(struct spinand_device *spinand,
+			      bool enable);
 
 	const struct spinand_fact_otp *fact_otp;
 	const struct spinand_user_otp *user_otp;
-- 
2.25.1