Re: [PATCH] staging: gdm724x: fixed two macros by adding brackets

[Greg KH]

On Mon, Aug 31, 2020 at 06:03:32PM +0200, antoniprzybylik wrote:
> Added brackets to two macros.

That says _what_ you did, but not _why_ you did it.

Why did you do it?  What does this fix?

Does it make sense to do this?

And why these two macros?  Be specific please.

> 
> Signed-off-by: Antoni Przybylik <antoni.przybylik@xxxxx>
> ---
>  drivers/staging/gdm724x/gdm_tty.c   | 3 +--
>  drivers/staging/gdm724x/netlink_k.c | 2 +-
>  2 files changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/staging/gdm724x/gdm_tty.c b/drivers/staging/gdm724x/gdm_tty.c
> index 6e813693a766..5cd94347bf78 100644
> --- a/drivers/staging/gdm724x/gdm_tty.c
> +++ b/drivers/staging/gdm724x/gdm_tty.c
> @@ -27,7 +27,7 @@
>  
>  #define MUX_TX_MAX_SIZE 2048
>  
> -#define GDM_TTY_READY(gdm) (gdm && gdm->tty_dev && gdm->port.count)
> +#define GDM_TTY_READY(gdm) ((gdm) && (gdm)->tty_dev && (gdm)->port.count)
>  
>  static struct tty_driver *gdm_driver[TTY_MAX_COUNT];
>  static struct gdm *gdm_table[TTY_MAX_COUNT][GDM_TTY_MINOR];
> @@ -323,4 +323,3 @@ void unregister_lte_tty_driver(void)
>  		}
>  	}
>  }
> -

You also deleted a line without saying so :(

> diff --git a/drivers/staging/gdm724x/netlink_k.c b/drivers/staging/gdm724x/netlink_k.c
> index 7902e52a699b..399b7b4b536f 100644
> --- a/drivers/staging/gdm724x/netlink_k.c
> +++ b/drivers/staging/gdm724x/netlink_k.c
> @@ -20,7 +20,7 @@ static DEFINE_MUTEX(netlink_mutex);
>  #define ND_NLMSG_DATA(nlh)	((void *)((char *)NLMSG_DATA(nlh) + \
>  						  ND_IFINDEX_LEN))
>  #define ND_NLMSG_S_LEN(len)	(len + ND_IFINDEX_LEN)
> -#define ND_NLMSG_R_LEN(nlh)	(nlh->nlmsg_len - ND_IFINDEX_LEN)
> +#define ND_NLMSG_R_LEN(nlh)	((nlh)->nlmsg_len - ND_IFINDEX_LEN)

Does that really make sense to change?

thanks,

greg k-h