spi: microchip-core: use XOR instead of ANDNOT to fix the logic

Use XOR instead of ANDNOT to fix the logic. The current approach with (foo & BAR & ~baz) is harder to process, and it proved to be wrong, than more usual pattern for the comparing misconfiguration using ((foo ^ baz) & BAR) which can be read as "find all different bits between foo and baz that are related to BAR (mask)". Besides that it makes the binary code shorter.

Function old new delta
mchp_corespi_setup 103 99 -4

---

Updated the commit message, added Fixes and Test-by tags, and sent as standalone patch.

 drivers/spi/spi-microchip-core-spi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 89e40fc45d73..c8ebb58e0369 100644
@@ -161,7 +161,7 @@ static int mchp_corespi_setup(struct spi_device *spi)
 		return -EOPNOTSUPP;
 	}
 
-	if (spi->mode & SPI_MODE_X_MASK & ~spi->controller->mode_bits) {
+	if ((spi->mode ^ spi->controller->mode_bits) & SPI_MODE_X_MASK) {
 		dev_err(&spi->dev, "incompatible CPOL/CPHA, must match controller's Motorola mode\n");
 		return -EINVAL;
 	}

2.50.1

Applied to

https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next

Thanks!

[1/1] spi: microchip-core: use XOR instead of ANDNOT to fix the logic

      commit: 19a4505a7a5d4eea70f1a42d601c25d730922fdf

All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced.

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Thanks,
Mark