Re: [PATCH v2] drm: Fix drm_fixp2int_round() making it add 0.5

[Maíra Canal]

Hi Melissa,

On 3/17/24 14:50, Melissa Wen wrote:
> On 03/16, Arthur Grillo wrote:
> > As well noted by Pekka[1], the rounding of drm_fixp2int_round is wrong.
> > To round a number, you need to add 0.5 to the number and floor that,
> > drm_fixp2int_round() is adding 0.0000076. Make it add 0.5.
> >
> > [1]: https://lore.kernel.org/all/20240301135327.22efe0dd.pekka.paalanen@xxxxxxxxxxxxx/
> >
> > Fixes: 8b25320887d7 ("drm: Add fixed-point helper to get rounded integer values")
> > Suggested-by: Pekka Paalanen <pekka.paalanen@xxxxxxxxxxxxx>
> > Reviewed-by: Harry Wentland <harry.wentland@xxxxxxx>
> > Signed-off-by: Arthur Grillo <arthurgrillo@xxxxxxxxxx>
>
> Great, thanks!
>
> Reviewed-by: Melissa Wen <mwen@xxxxxxxxxx>
>
> I'll apply to drm-misc-next.

Shouldn't this patch be applied in drm-misc-fixes?

Best Regards,
- Maíra

> Melissa
>
> > ---
> > Changes in v2:
> > - Add Fixes tag (Melissa Wen)
> > - Remove DRM_FIXED_POINT_HALF (Melissa Wen)
> > - Link to v1: https://lore.kernel.org/all/20240306-louis-vkms-conv-v1-1-5bfe7d129fdd@xxxxxxxxxx/
> > ---
> >   include/drm/drm_fixed.h | 3 +--
> >   1 file changed, 1 insertion(+), 2 deletions(-)
> >
> > diff --git a/include/drm/drm_fixed.h b/include/drm/drm_fixed.h
> > index 0c9f917a4d4b..81572d32db0c 100644
> > --- a/include/drm/drm_fixed.h
> > +++ b/include/drm/drm_fixed.h
> > @@ -71,7 +71,6 @@ static inline u32 dfixed_div(fixed20_12 A, fixed20_12 B)
> >   }
> >   
> >   #define DRM_FIXED_POINT		32
> > -#define DRM_FIXED_POINT_HALF	16
> >   #define DRM_FIXED_ONE		(1ULL << DRM_FIXED_POINT)
> >   #define DRM_FIXED_DECIMAL_MASK	(DRM_FIXED_ONE - 1)
> >   #define DRM_FIXED_DIGITS_MASK	(~DRM_FIXED_DECIMAL_MASK)
> > @@ -90,7 +89,7 @@ static inline int drm_fixp2int(s64 a)
> >   
> >   static inline int drm_fixp2int_round(s64 a)
> >   {
> > -	return drm_fixp2int(a + (1 << (DRM_FIXED_POINT_HALF - 1)));
> > +	return drm_fixp2int(a + DRM_FIXED_ONE / 2);
> >   }
> >   
> >   static inline int drm_fixp2int_ceil(s64 a)
> >
> > ---
> > base-commit: f89632a9e5fa6c4787c14458cd42a9ef42025434
> > change-id: 20240315-drm_fixed-c680ba078ecb
> >
> > Best regards,
> > --
> > Arthur Grillo <arthurgrillo@xxxxxxxxxx>