| Message ID | 30b2a315b36e1ee16c0217b32b95a605@jessamine.co.uk (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | spi: spi-imx: fix off-by-one in mx51 CPU mode burst length | expand |
From: Adam Butcher <adam@jessamine.co.uk> [Apologies, rubbish mailer corrupted the previous re-addressed post] 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@nxp.com/ Link: https://lore.kernel.org/all/20240204091912.36488-1-carlos.song@nxp.com/ Fixes: 992e1211dc91 ("spi: imx: fix the burst length at DMA mode and CPU mode") Signed-off-by: Adam Butcher <adam@jessamine.co.uk> --- 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; } }
On Wed, Mar 13, 2024 at 06:13:54PM -0000, Adam Butcher wrote: > From: Adam Butcher <adam@jessamine.co.uk> > > [Apologies, rubbish mailer corrupted the previous re-addressed post] Please put administrative stuff like this after the --- so that it doesn't end up in the changelog. Hopefully none of the tooling gets confused by having the same thing posted twice with two different contents...
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; }