[v3] spi: s3c64xx: straightforward cleanup

[PATCH v3 16/17] spi: s3c64xx: drop a superfluous bitwise NOT operation

Posted by Tudor Ambarus 1 year, 11 months ago

val &= ~mask;
val |= mask;

is equivalent to:
val |= mask;

Drop the superfluous bitwise NOT operation.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
---
 drivers/spi/spi-s3c64xx.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index e9344fe71e56..43b888c8812e 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -1089,7 +1089,6 @@ static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd)
 
 	val = readl(regs + S3C64XX_SPI_MODE_CFG);
 	val &= ~S3C64XX_SPI_MODE_4BURST;
-	val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
 	val |= (S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
 	writel(val, regs + S3C64XX_SPI_MODE_CFG);
 
-- 
2.43.0.429.g432eaa2c6b-goog

Re: [PATCH v3 16/17] spi: s3c64xx: drop a superfluous bitwise NOT operation

Posted by Sam Protsenko 1 year, 11 months ago

On Fri, Jan 26, 2024 at 11:16 AM Tudor Ambarus <tudor.ambarus@linaro.org> wrote:
>
> val &= ~mask;
> val |= mask;
>
> is equivalent to:
> val |= mask;
>
> Drop the superfluous bitwise NOT operation.
>
> Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
> ---

That's much more clear. Also I'm pretty sure if you compare .o file
before and after the patch, they would be identical -- another way to
argue the patch has no functional change.

Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>

>  drivers/spi/spi-s3c64xx.c | 1 -
>  1 file changed, 1 deletion(-)
>
> diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
> index e9344fe71e56..43b888c8812e 100644
> --- a/drivers/spi/spi-s3c64xx.c
> +++ b/drivers/spi/spi-s3c64xx.c
> @@ -1089,7 +1089,6 @@ static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd)
>
>         val = readl(regs + S3C64XX_SPI_MODE_CFG);
>         val &= ~S3C64XX_SPI_MODE_4BURST;
> -       val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
>         val |= (S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
>         writel(val, regs + S3C64XX_SPI_MODE_CFG);
>
> --
> 2.43.0.429.g432eaa2c6b-goog
>