[U-Boot] [PATCH 2/3] sf: Read back and check once spansion quad bit set

Jagan Teki jteki at openedev.com
Tue Dec 15 09:24:21 CET 2015


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 at ti.com>
Cc: Mugunthan V N <mugunthanvnm at ti.com>
Cc: Simon Glass <sjg at chromium.org>
Cc: Bin Meng <bmeng.cn at gmail.com>
Cc: Michal Simek <michal.simek at xilinx.com>
Cc: Siva Durga Prasad Paladugu <sivadur at xilinx.com>
Signed-off-by: Jagan Teki <jteki at 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 fc1538c..2e21eaa 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;
-- 
1.9.1



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