Adds a function to interpolate against two points, this is carried arount as a helper function by tons of drivers. Signed-off-by: Craig Tatlor <ctatlor97@xxxxxxxxx> Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx> --- include/linux/fixp-arith.h | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/include/linux/fixp-arith.h b/include/linux/fixp-arith.h index d4686fe1cac7..b9e2bb59a734 100644 --- a/include/linux/fixp-arith.h +++ b/include/linux/fixp-arith.h @@ -153,4 +153,24 @@ static inline s32 fixp_sin32_rad(u32 radians, u32 twopi) #define fixp_cos32_rad(rad, twopi) \ fixp_sin32_rad(rad + twopi / 4, twopi) + +/** + * fixp_linear_interpolate() - interpolates a value from two known points + * + * @x0: x value of point 0 + * @y0: y value of point 0 + * @x1: x value of point 1 + * @y1: y value of point 1 + * @x: the linear interpolant + */ +static inline int fixp_linear_interpolate(int x0, int y0, int x1, int y1, int x) +{ + if (y0 == y1 || x == x0) + return y0; + if (x1 == x0 || x == x1) + return y1; + + return y0 + ((y1 - y0) * (x - x0) / (x1 - x0)); +} + #endif -- 2.17.0 -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html