[PATCH 05/13] mtd: spinand: Add adjust_op() in manufacturer_ops to modify the ops for manufacturer specific changes

[Apurva Nandan]

Manufacturers might use a variation of standard SPI NAND flash
instructions, e.g. Winbond W35N01JW changes the dummy cycle length for
read register commands when in Octal DTR mode.

Add new function in manufacturer_ops: adjust_op(), which can be called
to correct the spi_mem op for any alteration in the instruction made by
the manufacturers. And hence, this function can also be used for
incorporating variations of SPI instructions in Octal DTR mode.

Datasheet: https://www.winbond.com/export/sites/winbond/datasheet/W35N01JW_Datasheet_Brief.pdf

Signed-off-by: Apurva Nandan <a-nandan@xxxxxx>
---
 drivers/mtd/nand/spi/core.c | 3 +++
 include/linux/mtd/spinand.h | 4 ++++
 2 files changed, 7 insertions(+)

diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c
index a5334ad34f96..1e619b6d777f 100644
--- a/drivers/mtd/nand/spi/core.c
+++ b/drivers/mtd/nand/spi/core.c
@@ -63,6 +63,9 @@ static void spinand_setup_op(const struct spinand_device *spinand,
 		op->data.buswidth = op_buswidth;
 		op->data.dtr = op_is_dtr;
 	}
+
+	if (spinand->manufacturer->ops->adjust_op)
+		spinand->manufacturer->ops->adjust_op(op, spinand->reg_proto);
 }
 
 static void spinand_setup_reg_op(const struct spinand_device *spinand,
diff --git a/include/linux/mtd/spinand.h b/include/linux/mtd/spinand.h
index f6093cd98d7b..ebb19b2cec84 100644
--- a/include/linux/mtd/spinand.h
+++ b/include/linux/mtd/spinand.h
@@ -257,6 +257,8 @@ struct spinand_devid {
 /**
  * struct manufacurer_ops - SPI NAND manufacturer specific operations
  * @init: initialize a SPI NAND device
+ * @adjust_op: modify the ops for any variation in their cmd, address, dummy or
+ *	       data phase by the manufacturer
  * @cleanup: cleanup a SPI NAND device
  *
  * Each SPI NAND manufacturer driver should implement this interface so that
@@ -264,6 +266,8 @@ struct spinand_devid {
  */
 struct spinand_manufacturer_ops {
 	int (*init)(struct spinand_device *spinand);
+	void (*adjust_op)(struct spi_mem_op *op,
+			  const enum spinand_proto reg_proto);
 	void (*cleanup)(struct spinand_device *spinand);
 };
 
-- 
2.17.1