[PATCH v1 1/7] mtd: spi-nor: fix the wrong dummy value

Huang Shijie b32955 at freescale.com
Wed Apr 23 03:16:49 PDT 2014


For the DDR Quad read, the dummy cycles maybe 3 or 6 which is less then 8.
The dummy cycles is actually 8 for SPI fast/dual/quad read.

This patch makes preparations for the DDR quad read, it fixes the wrong dummy
value for both the spi-nor.c and m25p80.c.

Signed-off-by: Huang Shijie <b32955 at freescale.com>
---
 drivers/mtd/devices/m25p80.c  |    5 ++++-
 drivers/mtd/spi-nor/spi-nor.c |    2 +-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
index 1557d8f..693e25f 100644
--- a/drivers/mtd/devices/m25p80.c
+++ b/drivers/mtd/devices/m25p80.c
@@ -128,9 +128,12 @@ static int m25p80_read(struct spi_nor *nor, loff_t from, size_t len,
 	struct spi_device *spi = flash->spi;
 	struct spi_transfer t[2];
 	struct spi_message m;
-	int dummy = nor->read_dummy;
+	unsigned int dummy = nor->read_dummy;
 	int ret;
 
+	/* convert the dummy cycles to the number of byte */
+	dummy /= 8;
+
 	/* Wait till previous write/erase is done. */
 	ret = nor->wait_till_ready(nor);
 	if (ret)
diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index f76f3fc..1a12f81 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -77,7 +77,7 @@ static inline int spi_nor_read_dummy_cycles(struct spi_nor *nor)
 	case SPI_NOR_FAST:
 	case SPI_NOR_DUAL:
 	case SPI_NOR_QUAD:
-		return 1;
+		return 8;
 	case SPI_NOR_NORMAL:
 		return 0;
 	}
-- 
1.7.2.rc3




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