spi: flags 'SPI_CONTROLLER_MUST_RX' and 'SPI_CONTROLLER_MUST_TX' can't be coexit...

since chip spi driver need get the transfer direction by 'tx_buf' and
'rx_buf' of 'struct spi_transfer' in 'SPI_3WIRE' mode.

so, we need bypass 'SPI_CONTROLLER_MUST_RX' and 'SPI_CONTROLLER_MUST_TX'
feature in 'SPI_3WIRE' mode

Signed-off-by: dillon min <dillon.minfei@gmail.com>
Link: https://lore.kernel.org/r/1590378348-8115-9-git-send-email-dillon.minfei@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index c765c96..9d0b3c2 100644 (file)
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1023,7 +1023,8 @@ static int spi_map_msg(struct spi_controller *ctlr, struct spi_message *msg)
        void *tmp;
        unsigned int max_tx, max_rx;
 
-       if (ctlr->flags & (SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX)) {
+       if ((ctlr->flags & (SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX))
+               && !(msg->spi->mode & SPI_3WIRE)) {
                max_tx = 0;
                max_rx = 0;