[PATCH v5 04/13] spi: spidev_test: reject zero-length transfers

[Jonas Rebmann]

Providing an empty file or empty string to spidev_test is bound to fail
because spidev_test expects the write to return greater than zero.

Reject requests to transfer an empty buffer earlier.

Signed-off-by: Jonas Rebmann <jre@xxxxxxxxxxxxxx>
---
 tools/spi/spidev_test.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/tools/spi/spidev_test.c b/tools/spi/spidev_test.c
index b2940a25b7a8..49d40aa6d0ec 100644
--- a/tools/spi/spidev_test.c
+++ b/tools/spi/spidev_test.c
@@ -129,6 +129,9 @@ static void transfer(int fd, uint8_t const *tx, uint8_t const *rx, size_t len)
 		.bits_per_word = bits,
 	};
 
+	if (!len)
+		pabort("can't transfer an empty buffer");
+
 	if (mode & SPI_TX_OCTAL)
 		tr.tx_nbits = 8;
 	else if (mode & SPI_TX_QUAD)

-- 
2.56.0.rc0.108.gf0ef1b96a0