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From:   dillon.minfei@gmail.com
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        mcoquelin.stm32@gmail.com, alexandre.torgue@st.com,
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        dillon min <dillon.minfei@gmail.com>
Subject: [PATCH v5 8/8] spi: flags 'SPI_CONTROLLER_MUST_RX' and 'SPI_CONTROLLER_MUST_TX' can't be coexit with 'SPI_3WIRE' mode
Date:   Mon, 25 May 2020 11:41:02 +0800
Message-Id: <1590378062-7965-9-git-send-email-dillon.minfei@gmail.com>
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 <1590378062-7965-1-git-send-email-dillon.minfei@gmail.com>
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From: dillon min <dillon.minfei@gmail.com>

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>
---
 drivers/spi/spi.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index c92c894..f884411 100644
--- 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;
 
-- 
2.7.4