From: Adam Butcher <adam@xxxxxxxxxxxxxxx>
992e1211dc91 ("spi: imx: fix the burst length at DMA mode and CPU mode")
corrects three cases of setting the ECSPI burst length but erroneously
leaves the in-range CPU case one bit to big (in that register a value of
0 means 1 bit). The effect was that transmissions that should have been
8-bit bytes appeared as 9-bit causing failed communication with SPI
devices.
It seems the original patch submission up to v4 did not contain the bug.
It was introduced in the v5 update.
Link:
https://lore.kernel.org/all/20240201105451.507005-1-carlos.song@xxxxxxx/
Link:
https://lore.kernel.org/all/20240204091912.36488-1-carlos.song@xxxxxxx/
Fixes: 992e1211dc91 ("spi: imx: fix the burst length at DMA mode and CPU
mode")
Signed-off-by: Adam Butcher <adam@xxxxxxxxxxxxxxx>
---
drivers/spi/spi-imx.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index 7c1fcd5ed52f7..100552e6c56bc 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -743,8 +743,8 @@ static int mx51_ecspi_prepare_transfer(struct
spi_imx_data *spi_imx,
ctrl |= (MX51_ECSPI_CTRL_MAX_BURST * BITS_PER_BYTE - 1)
<< MX51_ECSPI_CTRL_BL_OFFSET;
else
- ctrl |= spi_imx->count / DIV_ROUND_UP(spi_imx->bits_per_word,
- BITS_PER_BYTE) * spi_imx->bits_per_word
+ ctrl |= (spi_imx->count / DIV_ROUND_UP(spi_imx->bits_per_word,
+ BITS_PER_BYTE) * spi_imx->bits_per_word - 1)
<< MX51_ECSPI_CTRL_BL_OFFSET;
}
}
--
2.43.0
