[PATCH] mtd: spi-nor: Fix the number of bytes for the dummy cycles

Allen-KH Cheng allen-kh.cheng at mediatek.com
Mon Oct 31 05:46:33 PDT 2022


The number of bytes used by spi_nor_spimem_check_readop() may be
incorrect for the dummy cycles. Since nor->read_dummy is not initialized
before spi_nor_spimem_adjust_hwcaps().

We use both mode and wait state clock cycles instead of nor->read_dummy.

Fixes: 0e30f47232ab ("mtd: spi-nor: add support for DTR protocol")
Co-developed-by: Bayi Cheng <bayi.cheng at mediatek.com>
Signed-off-by: Bayi Cheng <bayi.cheng at mediatek.com>
Signed-off-by: Allen-KH Cheng <allen-kh.cheng at mediatek.com>
---
 drivers/mtd/spi-nor/core.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index 6c921eb3fadb..8b9c318a0ad4 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -1914,7 +1914,8 @@ static int spi_nor_spimem_check_readop(struct spi_nor *nor,
 	spi_nor_spimem_setup_op(nor, &op, read->proto);
 
 	/* convert the dummy cycles to the number of bytes */
-	op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8;
+	op.dummy.nbytes = (read->num_mode_clocks + read->num_wait_states) *
+			  op.dummy.buswidth / 8;
 	if (spi_nor_protocol_is_dtr(nor->read_proto))
 		op.dummy.nbytes *= 2;
 
-- 
2.18.0




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