From: Takahiro Kuwano <Takahiro.Kuwano@xxxxxxxxxxxx>
CFR2V[7] is assigned to Flash's address mode (3- or 4-ybte) and must not
be changed when writing MEMLAT (CFR2V[3:0]). CFR2V must be read first,
modified only CFR2V[3:0], then written back.
Fixes: c3266af101f2 ("mtd: spi-nor: spansion: add support for Cypress Semper flash")
Signed-off-by: Takahiro Kuwano <Takahiro.Kuwano@xxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
drivers/mtd/spi-nor/spansion.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/drivers/mtd/spi-nor/spansion.c b/drivers/mtd/spi-nor/spansion.c
index f2f4bc060f5e..7804be3a9f2a 100644
--- a/drivers/mtd/spi-nor/spansion.c
+++ b/drivers/mtd/spi-nor/spansion.c
@@ -27,6 +27,7 @@
#define SPINOR_REG_CYPRESS_CFR2 0x3
#define SPINOR_REG_CYPRESS_CFR2V \
(SPINOR_REG_CYPRESS_VREG + SPINOR_REG_CYPRESS_CFR2)
+#define SPINOR_REG_CYPRESS_CFR2_MEMLAT_MASK GENMASK(3, 0)
#define SPINOR_REG_CYPRESS_CFR2_MEMLAT_11_24 0xb
#define SPINOR_REG_CYPRESS_CFR2_ADRBYT BIT(7)
#define SPINOR_REG_CYPRESS_CFR3 0x4
@@ -162,8 +163,17 @@ static int cypress_nor_octal_dtr_en(struct spi_nor *nor)
int ret;
u8 addr_mode_nbytes = nor->params->addr_mode_nbytes;
+ op = (struct spi_mem_op)
+ CYPRESS_NOR_RD_ANY_REG_OP(addr_mode_nbytes,
+ SPINOR_REG_CYPRESS_CFR2V, 0, buf);
+
+ ret = spi_nor_read_any_reg(nor, &op, nor->reg_proto);
+ if (ret)
+ return ret;
+
/* Use 24 dummy cycles for memory array reads. */
- *buf = SPINOR_REG_CYPRESS_CFR2_MEMLAT_11_24;
+ *buf &= ~SPINOR_REG_CYPRESS_CFR2_MEMLAT_MASK;
+ *buf |= SPINOR_REG_CYPRESS_CFR2_MEMLAT_11_24;
op = (struct spi_mem_op)
CYPRESS_NOR_WR_ANY_REG_OP(addr_mode_nbytes,
SPINOR_REG_CYPRESS_CFR2V, 1, buf);
--
2.34.1
