drm/vkms: Round fixp2int conversion in lerp_u16

Harry Wentland · gregkh · commit 665de082f3cb · 2025-03-22T12:54:20.000-07:00
[ Upstream commit 8ec43c5 ] fixp2int always rounds down, fixp2int_ceil rounds up. We need the new fixp2int_round. Signed-off-by: Alex Hung <alex.hung@amd.com> Signed-off-by: Harry Wentland <harry.wentland@amd.com> Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com> Link: https://patchwork.freedesktop.org/patch/msgid/20241220043410.416867-3-alex.hung@amd.com Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c
@@ -98,7 +98,7 @@ static u16 lerp_u16(u16 a, u16 b, s64 t)
 
 	s64 delta = drm_fixp_mul(b_fp - a_fp,  t);
 
-	return drm_fixp2int(a_fp + delta);
+	return drm_fixp2int_round(a_fp + delta);
 }
 
 static s64 get_lut_index(const struct vkms_color_lut *lut, u16 channel_value)

Original file line number	Diff line number	Diff line change
`@@ -98,7 +98,7 @@ static u16 lerp_u16(u16 a, u16 b, s64 t)`
`98`	`98`
`99`	`99`	`s64 delta = drm_fixp_mul(b_fp - a_fp, t);`
`100`	`100`
`101`		`- return drm_fixp2int(a_fp + delta);`
	`101`	`+ return drm_fixp2int_round(a_fp + delta);`
`102`	`102`	`}`
`103`	`103`
`104`	`104`	`static s64 get_lut_index(const struct vkms_color_lut *lut, u16 channel_value)`