The SPI core enforces that we always use the next power-of-two number of
bytes to store words. As a result, a 24 bits word will be stored in 4
bytes.
This commit fixes the spi_imx_bytes_per_word function to return the
correct number of bytes.
This also allows to get rid of unnecessary checks in the can_dma
function, since the SPI core validates that we always have a transfer
length that is a multiple of the number of bytes per word.
Signed-off-by: Maxime Chevallier <maxime.chevall...@bootlin.com>
---
drivers/spi/spi-imx.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index ecafbda5ec94..3ae706dac660 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -202,7 +202,12 @@ static unsigned int spi_imx_clkdiv_2(unsigned int fin,
static int spi_imx_bytes_per_word(const int bits_per_word)
{
- return DIV_ROUND_UP(bits_per_word, BITS_PER_BYTE);
+ if (bits_per_word <= 8)
+ return 1;
+ else if (bits_per_word <= 16)
+ return 2;
+ else
+ return 4;
}
static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
@@ -219,9 +224,6 @@ static bool spi_imx_can_dma(struct spi_master *master,
struct spi_device *spi,
bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
- if (bytes_per_word != 1 && bytes_per_word != 2 && bytes_per_word != 4)
- return false;
-
for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
if (!(transfer->len % (i * bytes_per_word)))
break;
--
2.11.0
