From ffecb0fc840707d7aadf42364ae596f998a3d52f Mon Sep 17 00:00:00 2001
From: Jagan Teki <jteki@openedev.com>
Date: Tue, 15 Dec 2015 12:28:39 +0530
Subject: [PATCH] sf: Read back and check once spansion quad bit set
One spansion quad bit set using CR, it's good to
read back and check the written bit and also if
it's already been set check for the bit and return.
Cc: Vignesh R <vigneshr@ti.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Bin Meng <bmeng.cn@gmail.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Siva Durga Prasad Paladugu <sivadur@xilinx.com>
Tested-by: Mugunthan V N <mugunthanvnm@ti.com>
Signed-off-by: Jagan Teki <jteki@openedev.com>
---
drivers/mtd/spi/spi_flash.c | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)
diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c
index d9124c5fc5..b7c0da46a2 100644
--- a/drivers/mtd/spi/spi_flash.c
+++ b/drivers/mtd/spi/spi_flash.c
@@ -862,12 +862,18 @@ static int spansion_quad_enable(struct spi_flash *flash)
if (ret < 0)
return ret;
- if (qeb_status & STATUS_QEB_WINSPAN) {
- debug("SF: winspan: QEB is already set\n");
- } else {
- ret = write_cr(flash, STATUS_QEB_WINSPAN);
- if (ret < 0)
- return ret;
+ if (qeb_status & STATUS_QEB_WINSPAN)
+ return 0;
+
+ ret = write_cr(flash, STATUS_QEB_WINSPAN);
+ if (ret < 0)
+ return ret;
+
+ /* read CR and check it */
+ ret = read_cr(flash, &qeb_status);
+ if (!(ret >= 0 && (qeb_status & STATUS_QEB_WINSPAN))) {
+ printf("SF: Spansion CR Quad bit not clear\n");
+ return -EINVAL;
}
return ret;
--
2.39.5