Re: [PATCH v8 13/25] m68k: Dispatch nvram_ops calls to Atari or Mac functions

[Arnd Bergmann]

On Wed, Dec 26, 2018 at 1:43 AM Finn Thain <fthain@xxxxxxxxxxxxxxxxxxx> wrote:

> +
> +static ssize_t m68k_nvram_get_size(void)
> +{
> +       if (MACH_IS_ATARI)
> +               return atari_nvram_get_size();
> +       else if (MACH_IS_MAC)
> +               return mac_pram_get_size();
> +       return -ENODEV;
> +}
> +
> +/* Atari device drivers call .read (to get checksum validation) whereas
> + * Mac and PowerMac device drivers just use .read_byte.
> + */
> +const struct nvram_ops arch_nvram_ops = {
> +#ifdef CONFIG_MAC
> +       .read_byte      = m68k_nvram_read_byte,
> +       .write_byte     = m68k_nvram_write_byte,
> +#endif
> +#ifdef CONFIG_ATARI
> +       .read           = m68k_nvram_read,
> +       .write          = m68k_nvram_write,
> +       .set_checksum   = m68k_nvram_set_checksum,
> +       .initialize     = m68k_nvram_initialize,
> +#endif
> +       .get_size       = m68k_nvram_get_size,
> +};
> +EXPORT_SYMBOL(arch_nvram_ops);

Since the operations are almost entirely distinct, why not have two
separate 'nvram_ops' instances here that each refer to just
the set they actually need?

I was actually expecting one more patch here that would make the
arch_nvram_ops a pointer to one of multiple structures, which would
be easier to do with multiple copies, but I suppose there is no need
for that here (there might be on ppc, I have to look again).

       Arnd