[PATCH] m68k: Implement ndelay() as an inline function to force type checking/casting

Andy Shevchenko andy.shevchenko at gmail.com
Sun May 13 15:38:15 PDT 2018


On Sun, May 13, 2018 at 5:02 PM, Boris Brezillon
<boris.brezillon at bootlin.com> wrote:
> ndelay() is supposed to take an unsigned long, but if you define
> ndelay() as a macro and the caller pass an unsigned long long instead
> of an unsigned long, the unsigned long long to unsigned long cast is
> not done and we end up with an "undefined reference to `__udivdi3'"
> error at link time.

> -#define ndelay(n) __delay(DIV_ROUND_UP((n) * ((((HZSCALE) >> 11) * (loops_per_jiffy >> 11)) >> 6), 1000))
> +static inline void ndelay(unsigned long nsec)
> +{
> +       __delay(DIV_ROUND_UP(nsec *
> +                            ((((HZSCALE) >> 11) *

One pair of parens is redundant.

> +                              (loops_per_jiffy >> 11)) >> 6),
> +                            1000));

Can't you keep as one line as in original?

> +}
> +#define ndelay(n) ndelay(n)
>
>  #endif /* defined(_M68K_DELAY_H) */
> --
> 2.14.1
>



-- 
With Best Regards,
Andy Shevchenko



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