Hi Kieran, Thank you for the patch. On Thu, Apr 11, 2019 at 05:12:55PM +0100, Kieran Bingham wrote: > The 'mp' value is used through many calculations in determining the scaling > factors of the UDS. Factor this out so that it can be reused in further > calculations, and also ensure that if the BLADV control is ever changed only a > single function needs to be modified. > > Signed-off-by: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx> > --- > drivers/media/platform/vsp1/vsp1_uds.c | 22 ++++++++++++++-------- > 1 file changed, 14 insertions(+), 8 deletions(-) > > diff --git a/drivers/media/platform/vsp1/vsp1_uds.c b/drivers/media/platform/vsp1/vsp1_uds.c > index 27012af973b2..c71c24363d54 100644 > --- a/drivers/media/platform/vsp1/vsp1_uds.c > +++ b/drivers/media/platform/vsp1/vsp1_uds.c > @@ -46,6 +46,18 @@ void vsp1_uds_set_alpha(struct vsp1_entity *entity, struct vsp1_dl_body *dlb, > alpha << VI6_UDS_ALPVAL_VAL0_SHIFT); > } > > +/* > + * Determine the pre-filter multiplication value. This would benefit from a more detailed description, and in particular a definition of what "pre-filter" means. > + * > + * This calculation assumes that the BLADV control is unset. s/control/bit/ ? s/unset/not set/ ? > + */ > +static unsigned int uds_multiplier(int ratio) Should the function be renamed to uds_pre_multiplier() ? And isn't it a divisor ? :-) > +{ > + unsigned int mp = ratio / 4096; > + > + return mp < 4 ? 1 : (mp < 8 ? 2 : 4); > +} > + > /* > * uds_output_size - Return the output size for an input size and scaling ratio > * @input: input size in pixels > @@ -55,10 +67,7 @@ static unsigned int uds_output_size(unsigned int input, unsigned int ratio) > { > if (ratio > 4096) { > /* Down-scaling */ > - unsigned int mp; > - > - mp = ratio / 4096; > - mp = mp < 4 ? 1 : (mp < 8 ? 2 : 4); > + unsigned int mp = uds_multiplier(ratio); > > return (input - 1) / mp * mp * 4096 / ratio + 1; > } else { > @@ -88,10 +97,7 @@ static unsigned int uds_passband_width(unsigned int ratio) > { > if (ratio >= 4096) { > /* Down-scaling */ > - unsigned int mp; > - > - mp = ratio / 4096; > - mp = mp < 4 ? 1 : (mp < 8 ? 2 : 4); > + unsigned int mp = uds_multiplier(ratio); > > return 64 * 4096 * mp / ratio; > } else { -- Regards, Laurent Pinchart