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| author | Alain Volmat <alain.volmat@foss.st.com> | 2021-02-05 19:59:25 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-03-04 09:39:46 +0100 |
| commit | 2f6f38cb8629488d5c206ca89c88ae007731e380 (patch) | |
| tree | 7ce11af86bba60e93ad074be22e82b05c22298ef /drivers/spi | |
| parent | fd5560b4376efe3c1e79d86cfb2ff1b65737f459 (diff) | |
| download | linux-stable-2f6f38cb8629488d5c206ca89c88ae007731e380.tar.gz linux-stable-2f6f38cb8629488d5c206ca89c88ae007731e380.tar.bz2 linux-stable-2f6f38cb8629488d5c206ca89c88ae007731e380.zip | |
spi: stm32: properly handle 0 byte transfer
[ Upstream commit 2269f5a8b1a7b38651d62676b98182828f29d11a ]
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>
Link: https://lore.kernel.org/r/1612551572-495-2-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-stm32.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c index 8eb2644506dd..8d692f16d90a 100644 --- a/drivers/spi/spi-stm32.c +++ b/drivers/spi/spi-stm32.c @@ -992,6 +992,10 @@ 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; |