[PATCH v2 2/2] serial: 8250: Use BIT(x) for UART_{CAP,BUG}_*

Jiri Slaby jirislaby at kernel.org
Wed May 19 16:14:16 AEST 2021


On 19. 05. 21, 2:07, Andrew Jeffery wrote:
> BIT(x) improves readability and safety with respect to shifts.
> 
> Signed-off-by: Andrew Jeffery <andrew at aj.id.au>
> ---
>   drivers/tty/serial/8250/8250.h | 33 +++++++++++++++++----------------
>   1 file changed, 17 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h
> index 34aa2714f3c9..4fbf1088fad8 100644
> --- a/drivers/tty/serial/8250/8250.h
> +++ b/drivers/tty/serial/8250/8250.h
> @@ -7,6 +7,7 @@
>    *  Copyright (C) 2001 Russell King.
>    */
>   
> +#include <linux/bitops.h>
>   #include <linux/serial_8250.h>
>   #include <linux/serial_reg.h>
>   #include <linux/dmaengine.h>
> @@ -70,25 +71,25 @@ struct serial8250_config {
>   	unsigned int	flags;
>   };
>   
> -#define UART_CAP_FIFO	(1 << 8)	/* UART has FIFO */
> -#define UART_CAP_EFR	(1 << 9)	/* UART has EFR */
> -#define UART_CAP_SLEEP	(1 << 10)	/* UART has IER sleep */
> -#define UART_CAP_AFE	(1 << 11)	/* MCR-based hw flow control */
> -#define UART_CAP_UUE	(1 << 12)	/* UART needs IER bit 6 set (Xscale) */
> -#define UART_CAP_RTOIE	(1 << 13)	/* UART needs IER bit 4 set (Xscale, Tegra) */
> -#define UART_CAP_HFIFO	(1 << 14)	/* UART has a "hidden" FIFO */
> -#define UART_CAP_RPM	(1 << 15)	/* Runtime PM is active while idle */
> -#define UART_CAP_IRDA	(1 << 16)	/* UART supports IrDA line discipline */
> -#define UART_CAP_MINI	(1 << 17)	/* Mini UART on BCM283X family lacks:
> +#define UART_CAP_FIFO	BIT(8)	/* UART has FIFO */
> +#define UART_CAP_EFR	BIT(9)	/* UART has EFR */
> +#define UART_CAP_SLEEP	BIT(10)	/* UART has IER sleep */


Perfect, except the include: BIT is not defined in bitops.h, but in 
bits.h (which includes vdso/bits.h). In fact, bitops.h includes bits.h 
too, but it's superfluous to include all those bitops.

thanks,
-- 
-- 
js
suse labs


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