The Cadence driver does not support anything else than repeating the
command opcode twice while in octal DTR mode. Make this clear by
checking for this in the ->supports_op() hook.

Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Miquel Raynal (Schneider Electric) <miquel.raynal@bootlin.com>
---
 drivers/spi/spi-cadence-quadspi.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c
index 06f6c5979229..fc9f6e8dd549 100644
--- a/drivers/spi/spi-cadence-quadspi.c
+++ b/drivers/spi/spi-cadence-quadspi.c
@@ -1531,6 +1531,10 @@ static bool cqspi_supports_mem_op(struct spi_mem *mem,
 			return false;
 		if (op->data.nbytes && op->data.buswidth != 8)
 			return false;
+
+		/* A single opcode is supported, it will be repeated */
+		if ((op->cmd.opcode >> 8) != (op->cmd.opcode & 0xFF))
+			return false;
 	} else if (!all_false) {
 		/* Mixed DTR modes are not supported. */
 		return false;

-- 
2.51.1