[PATCH 2/4] lib: utils: Improve fdt_serial_init

[Anup Patel]

On Tue, May 9, 2023 at 8:17 PM Xiang W <wxjstz at 126.com> wrote:
>
> A final check of all DT nodes does not necessarily find a match, so
> SBI_ENODEV needs to be returned. Optimize removal of current_driver.
>
> Signed-off-by: Xiang W <wxjstz at 126.com>

Looks good to me.

Reviewed-by: Anup Patel <anup at brainfault.org>

Regards,
Anup

> ---
>  lib/utils/serial/fdt_serial.c | 48 +++++++++++++----------------------
>  1 file changed, 17 insertions(+), 31 deletions(-)
>
> diff --git a/lib/utils/serial/fdt_serial.c b/lib/utils/serial/fdt_serial.c
> index 1a4bf9e..0baa722 100644
> --- a/lib/utils/serial/fdt_serial.c
> +++ b/lib/utils/serial/fdt_serial.c
> @@ -17,13 +17,6 @@
>  extern struct fdt_serial *fdt_serial_drivers[];
>  extern unsigned long fdt_serial_drivers_size;
>
> -static struct fdt_serial dummy = {
> -       .match_table = NULL,
> -       .init = NULL,
> -};
> -
> -static struct fdt_serial *current_driver = &dummy;
> -
>  int fdt_serial_init(void)
>  {
>         const void *prop;
> @@ -57,20 +50,15 @@ int fdt_serial_init(void)
>                 if (!match)
>                         continue;
>
> -               if (drv->init) {
> -                       rc = drv->init(fdt, noff, match);
> -                       if (rc == SBI_ENODEV)
> -                               continue;
> -                       if (rc)
> -                               return rc;
> -               }
> -               current_driver = drv;
> -               break;
> -       }
> +               /* drv->init must not be NULL */
> +               if (drv->init == NULL)
> +                       return SBI_EFAIL;
>
> -       /* Check if we found desired driver */
> -       if (current_driver != &dummy)
> -               goto done;
> +               rc = drv->init(fdt, noff, match);
> +               if (rc == SBI_ENODEV)
> +                       continue;
> +               return rc;
> +       }
>
>         /* Lastly check all DT nodes */
>         for (pos = 0; pos < fdt_serial_drivers_size; pos++) {
> @@ -80,17 +68,15 @@ int fdt_serial_init(void)
>                 if (noff < 0)
>                         continue;
>
> -               if (drv->init) {
> -                       rc = drv->init(fdt, noff, match);
> -                       if (rc == SBI_ENODEV)
> -                               continue;
> -                       if (rc)
> -                               return rc;
> -               }
> -               current_driver = drv;
> -               break;
> +               /* drv->init must not be NULL */
> +               if (drv->init == NULL)
> +                       return SBI_EFAIL;
> +
> +               rc = drv->init(fdt, noff, match);
> +               if (rc == SBI_ENODEV)
> +                       continue;
> +               return rc;
>         }
>
> -done:
> -       return 0;
> +       return SBI_ENODEV;
>  }
> --
> 2.39.2
>