[PATCH v6 18/28] spi: spi-mem: Fix a DTR related check in spi_mem_dtr_supports_op()

[Miquel Raynal]

It seems that the number of command bytes must be "2" only when the
command itself is sent in DTR mode. The current logic checks if the
number of command bytes is "2" when any of the cycles is a DTR cycle. It
is likely that so far no device was actually mixing DTR/non-DTR cycles
in the same operation, explaining why this was left undetected until
now.

Fixes: 539cf68cd51b ("spi: spi-mem: add spi_mem_dtr_supports_op()")
Suggested-by: Boris Brezillon <boris.brezillon at collabora.com>
Signed-off-by: Miquel Raynal <miquel.raynal at bootlin.com>
---
 drivers/spi/spi-mem.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c
index 37f4443ce9a0..c4da0c9b05e9 100644
--- a/drivers/spi/spi-mem.c
+++ b/drivers/spi/spi-mem.c
@@ -163,7 +163,7 @@ static bool spi_mem_check_buswidth(struct spi_mem *mem,
 bool spi_mem_dtr_supports_op(struct spi_mem *mem,
 			     const struct spi_mem_op *op)
 {
-	if (op->cmd.nbytes != 2)
+	if (op->cmd.dtr && op->cmd.nbytes != 2)
 		return false;
 
 	return spi_mem_check_buswidth(mem, op);
-- 
2.27.0