[PATCH v2 03/10] spi-nor: intel-spi: Fix broken software sequencing codes

[Bin Meng]

There are two bugs in current intel_spi_sw_cycle():

- The 'data byte count' field should be the number of bytes
  transferred minus 1
- SSFSTS_CTL is the offset from ispi->sregs, not ispi->base

Signed-off-by: Bin Meng <bmeng.cn@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # v4.11+
Acked-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>

---

Changes in v2:
- Add stable kernel tags in the commit message

 drivers/mtd/spi-nor/intel-spi.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/mtd/spi-nor/intel-spi.c b/drivers/mtd/spi-nor/intel-spi.c
index 07626ca..263c6ab 100644
--- a/drivers/mtd/spi-nor/intel-spi.c
+++ b/drivers/mtd/spi-nor/intel-spi.c
@@ -426,7 +426,7 @@ static int intel_spi_sw_cycle(struct intel_spi *ispi, u8 opcode, int len)
 	if (ret < 0)
 		return ret;
 
-	val = (len << SSFSTS_CTL_DBC_SHIFT) | SSFSTS_CTL_DS;
+	val = ((len - 1) << SSFSTS_CTL_DBC_SHIFT) | SSFSTS_CTL_DS;
 	val |= ret << SSFSTS_CTL_COP_SHIFT;
 	val |= SSFSTS_CTL_FCERR | SSFSTS_CTL_FDONE;
 	val |= SSFSTS_CTL_SCGO;
@@ -436,7 +436,7 @@ static int intel_spi_sw_cycle(struct intel_spi *ispi, u8 opcode, int len)
 	if (ret)
 		return ret;
 
-	status = readl(ispi->base + SSFSTS_CTL);
+	status = readl(ispi->sregs + SSFSTS_CTL);
 	if (status & SSFSTS_CTL_FCERR)
 		return -EIO;
 	else if (status & SSFSTS_CTL_AEL)
-- 
2.9.2