[PATCH v3 12/17] mtd: spinand: Add mtd_suspend() to disable Octal DTR mode at suspend

[Apurva Nandan]

The flash might or might not have gone a power-down during sleep.
Hence, its SPI IO mode is unpredictable for the core at the time of
resume. To ensure proper reinitialization during resume, disable the
Octal DTR SPI IO mode and bring the flash to 1S-1S-1S mode when
performing suspend using mtd_suspend().

Signed-off-by: Apurva Nandan <a-nandan at ti.com>
---
 drivers/mtd/nand/spi/core.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c
index 2fd08085db6f..9d1c72634e5a 100644
--- a/drivers/mtd/nand/spi/core.c
+++ b/drivers/mtd/nand/spi/core.c
@@ -1307,6 +1307,16 @@ static void spinand_mtd_resume(struct mtd_info *mtd)
 	spinand_ecc_enable(spinand, false);
 }
 
+static int spinand_mtd_suspend(struct mtd_info *mtd)
+{
+	struct spinand_device *spinand = mtd_to_spinand(mtd);
+
+	if (spinand->ctrl_ops->protocol == SPINAND_8D_8D_8D)
+		return spinand_init_octal_dtr_disable(spinand);
+
+	return 0;
+}
+
 static int spinand_init(struct spinand_device *spinand)
 {
 	struct device *dev = &spinand->spimem->spi->dev;
@@ -1381,6 +1391,7 @@ static int spinand_init(struct spinand_device *spinand)
 	mtd->_erase = spinand_mtd_erase;
 	mtd->_max_bad_blocks = nanddev_mtd_max_bad_blocks;
 	mtd->_resume = spinand_mtd_resume;
+	mtd->_suspend = spinand_mtd_suspend;
 
 	if (nand->ecc.engine) {
 		ret = mtd_ooblayout_count_freebytes(mtd);
-- 
2.25.1