Re: [PATCH v4 08/13] serial: sh-sci: Introduced function pointers

Hi Thierry,

On Thu, 6 Mar 2025 at 16:26, Thierry Bultel
<[email protected]> wrote:
> The aim here is to prepare support for new sci controllers like
> the T2H/RSCI whose registers are too much different for being
> handled in common code.
>
> This named serial controller also has 32 bits register,
> so some return types had to be changed.
>
> The needed generic functions are no longer static, with prototypes
> defined in sh-sci-common.h so that they can be used from specific
> implementation in a separate file, to keep this driver as little
> changed as possible.
>
> For doing so, a set of 'ops' is added to struct sci_port.
>
> Signed-off-by: Thierry Bultel <[email protected]>
> ---
> Changes v3->v4:
>    - Add missing #include <bitfield.h>
>    - Remove sci_poll_get_char sci_poll_put_char from sh-sci-common.h (both
>      function are not used by rzsci yet).
>    - Add missing #ifdef around .poll_put_char pointer initialization.
>    - More registers to save & restore due to rebase on tty-next

Thanks for the update!

While most rough edges have been polished by now (thanks!), and the
driver seems to still work on a variety of platforms, I am still
worried about the impact of this change:
  - Maintainability and future bug fixing?
  - Performance of the additional indirections on slow platforms (SH)?

What do other people think?
Thanks!

Full series:
https://lore.kernel.org/all/[email protected]
My initial comments and RFC:
https://lore.kernel.org/all/CAMuHMdVD1dLP53V_zOhxpqazDdPDVafJ6iohY8u6WPQrmYH5Sw@mail.gmail.com

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds