spi: sun4i: Set bits_per_word_mask to only support 8 bits word length

This controller only supports 8 bits word length.
Set bits_per_word_mask so spi core will reject transfers that attempt to use
an unsupported bits_per_word value.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/spi/spi-sun4i.c b/drivers/spi/spi-sun4i.c
index 3f82705d0a27..d266a8702067 100644
--- a/drivers/spi/spi-sun4i.c
+++ b/drivers/spi/spi-sun4i.c
@@ -392,6 +392,7 @@ static int sun4i_spi_probe(struct platform_device *pdev)
         master->transfer_one = sun4i_spi_transfer_one;
         master->num_chipselect = 4;
         master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
+        master->bits_per_word_mask = SPI_BPW_MASK(8);
         master->dev.of_node = pdev->dev.of_node;
         master->auto_runtime_pm = true;