[cocci] [PATCH v3 2/6] coccinelle: misc: Add field_modify script

[Markus Elfring]

…
>> -reg &= ~mask;
>> -reg |= FIELD_PREP
>> +       FIELD_MODIFY
>>                    (mask,
>> +                  &reg,
>>                     val
>>                    );
…
> With this code variant, there is no space prior to &reg, here is the
> example code changes generated by the SmPL code as below, is this expected?
…
> +++ b/drivers/phy/starfive/phy-jh7110-dphy-tx.c
> @@ -244,8 +244,7 @@ static int stf_dphy_configure(struct phy
>         i = stf_dphy_get_config_index(bitrate);
> 
>         tmp = readl(dphy->topsys + STF_DPHY_APBIFSAIF_SYSCFG(100));
> -       tmp &= ~STF_DPHY_REFCLK_IN_SEL;
> -       tmp |= FIELD_PREP(STF_DPHY_REFCLK_IN_SEL, STF_DPHY_REFCLK_12M);
> +       FIELD_MODIFY(STF_DPHY_REFCLK_IN_SEL,&tmp, STF_DPHY_REFCLK_12M);
>         writel(tmp, dphy->topsys + STF_DPHY_APBIFSAIF_SYSCFG(100));

The Coccinelle software is still evolving somehow.
Thus your test result can trigger further development considerations.
I hope that clarifications and corresponding improvements can be achieved
also according to such source code layout concerns.

Regards,
Markus