[PATCH 4.14 070/125] spi: fix initial SPI_SR value in spi-fsl-dspi

From: Greg Kroah-Hartman
Date: Mon Jul 20 2020 - 11:46:50 EST


From: Angelo Dureghello <angelo@xxxxxxxx>

[ Upstream commit aa54c1c9d90e6db75190813907190fadcce1bf45 ]

On ColdFire mcf54418, using DSPI_DMA_MODE mode, spi transfers
at first boot stage are not succeding:

m25p80 spi0.1: unrecognized JEDEC id bytes: 00, 00, 00

The reason is the SPI_SR initial value set by the driver, that
is not clearing (not setting to 1) the RF_DF flag. After a tour
on the dspi hw modules that use this driver(Vybrid, ColdFire and
ls1021a) a better init value for SR register has been set.

Signed-off-by: Angelo Dureghello <angelo@xxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/spi/spi-fsl-dspi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c
index cce9e34306787..6da70a62e1964 100644
--- a/drivers/spi/spi-fsl-dspi.c
+++ b/drivers/spi/spi-fsl-dspi.c
@@ -76,7 +76,7 @@
#define SPI_SR 0x2c
#define SPI_SR_EOQF 0x10000000
#define SPI_SR_TCFQF 0x80000000
-#define SPI_SR_CLEAR 0xdaad0000
+#define SPI_SR_CLEAR 0x9aaf0000

#define SPI_RSER_TFFFE BIT(25)
#define SPI_RSER_TFFFD BIT(24)
--
2.25.1