[PATCH] spi: fsl: invert spisel_boot signal on MPC8309

From: Rasmus Villemoes
Date: Sat Jan 30 2021 - 11:26:25 EST


Commit 7a2da5d7960a ("spi: fsl: Fix driver breakage when SPI_CS_HIGH
is not set in spi->mode") broke our MPC8309 board by effectively
inverting the boolean value passed to fsl_spi_cs_control. The
SPISEL_BOOT signal is used as chipselect, but it's not a gpio, so
we cannot rely on gpiolib handling the polarity.

Adapt to the new world order by inverting the logic here. This does
assume that the slave sitting at the SPISEL_BOOT is active low, but
should that ever turn out not to be the case, one can create a stub
gpiochip driver controlling a single gpio (or rather, a single "spo",
special-purpose output).

Fixes: 7a2da5d7960a ("spi: fsl: Fix driver breakage when SPI_CS_HIGH is not set in spi->mode")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@xxxxxxxxx>
---
drivers/spi/spi-fsl-spi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/spi/spi-fsl-spi.c b/drivers/spi/spi-fsl-spi.c
index 6d8e0a05a535..e4a8d203f940 100644
--- a/drivers/spi/spi-fsl-spi.c
+++ b/drivers/spi/spi-fsl-spi.c
@@ -695,7 +695,7 @@ static void fsl_spi_cs_control(struct spi_device *spi, bool on)

if (WARN_ON_ONCE(!pinfo->immr_spi_cs))
return;
- iowrite32be(on ? SPI_BOOT_SEL_BIT : 0, pinfo->immr_spi_cs);
+ iowrite32be(on ? 0 : SPI_BOOT_SEL_BIT, pinfo->immr_spi_cs);
}
}

--
2.23.0