Re: [RFC PATCH 06/13] pinctrl: renesas: pinctrl-rzg2l: Make cfg to u64 in struct rzg2l_variable_pin_cfg

[Geert Uytterhoeven]

Hi Prabhakar,

On Tue, Mar 26, 2024 at 11:30 PM Prabhakar <prabhakar.csengg@xxxxxxxxx> wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
>
> Now that we have updated the macro PIN_CFG_MASK to allow for the maximum
> configuration bits, update the size of 'cfg' to 'u64' in the
> 'struct rzg2l_variable_pin_cfg'.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>

Thanks for your patch!

> --- a/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> +++ b/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> @@ -241,7 +241,7 @@ struct rzg2l_dedicated_configs {
>   * @pin: port pin
>   */
>  struct rzg2l_variable_pin_cfg {
> -       u32 cfg:20;
> +       u64 cfg:46;
>         u32 port:5;
>         u32 pin:3;

Doesn't this store the 46 cfg bits in a 64-bit word, and the 8 port
and pin bits in a different 32-bit word?  Worse, you'll get 4 bytes
of padding at the end of the structure.
Changing the port and pin to u64 should make sure everything is
stored together in a single 64-bit word.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68korg

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.
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