diff mbox series

[v2,1/8] spi: stm32: properly handle 0 byte transfer

Message ID 1612551572-495-2-git-send-email-alain.volmat@foss.st.com (mailing list archive)
State New, archived
Headers show
Series spi: stm32: fix and enhancements for spi-stm32 | expand

Commit Message

Alain Volmat Feb. 5, 2021, 6:59 p.m. UTC 
On 0 byte transfer request, return straight from the
xfer function after finalizing the transfer.

Fixes: dcbe0d84dfa5 ("spi: add driver for STM32 SPI controller")
Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
---
v2: remove useless spi_finalize_current_transfer

 drivers/spi/spi-stm32.c | 4 ++++
 1 file changed, 4 insertions(+)
diff mbox series

Patch

diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c
index db3e305d9ec4..6cdecd1c5ec7 100644
--- a/drivers/spi/spi-stm32.c
+++ b/drivers/spi/spi-stm32.c
@@ -1657,6 +1657,10 @@  static int stm32_spi_transfer_one(struct spi_master *master,
 	struct stm32_spi *spi = spi_master_get_devdata(master);
 	int ret;
 
+	/* Don't do anything on 0 bytes transfers */
+	if (transfer->len == 0)
+		return 0;
+
 	spi->tx_buf = transfer->tx_buf;
 	spi->rx_buf = transfer->rx_buf;
 	spi->tx_len = spi->tx_buf ? transfer->len : 0;