From 9d63f17661e25fd28714dac94bdebc4ff5b75f09 Mon Sep 17 00:00:00 2001
From: Bin Meng <bmeng.cn@gmail.com>
Date: Mon, 11 Sep 2017 02:41:53 -0700
Subject: [PATCH] spi-nor: intel-spi: Fix broken software sequencing codes
Git-commit: 9d63f17661e25fd28714dac94bdebc4ff5b75f09
Patch-mainline: v4.15-rc1
References: bsc#1073836

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@gmail.com>
Cc: <stable@vger.kernel.org> # v4.11+
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@wedev4u.fr>
Acked-by: Takashi Iwai <tiwai@suse.de>

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

--- a/drivers/mtd/spi-nor/intel-spi.c
+++ b/drivers/mtd/spi-nor/intel-spi.c
@@ -422,7 +422,7 @@ static int intel_spi_sw_cycle(struct int
 	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;
@@ -432,7 +432,7 @@ static int intel_spi_sw_cycle(struct int
 	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)