[RFC v2 4/5] drm: fixed: Add dfixed_frac

[Thierry Reding <thierry.reding-RM9K5IK7kjKj5M59NBduVrNAH6kLmebB@public.gmane.org>]

From: Robert Morell <rmorell-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>

This helper macro retrieves the fractional part of a fixed20_12 20.12
fixed-point number.

Signed-off-by: Robert Morell <rmorell-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
Signed-off-by: Olof Johansson <olofj-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
Signed-off-by: Thierry Reding <thierry.reding-RM9K5IK7kjKj5M59NBduVrNAH6kLmebB@public.gmane.org>
---
 include/drm/drm_fixed.h |    1 +
 1 file changed, 1 insertion(+)

diff --git a/include/drm/drm_fixed.h b/include/drm/drm_fixed.h
index 4a08a66..0ead502 100644
--- a/include/drm/drm_fixed.h
+++ b/include/drm/drm_fixed.h
@@ -37,6 +37,7 @@ typedef union dfixed {
 #define dfixed_init(A) { .full = dfixed_const((A)) }
 #define dfixed_init_half(A) { .full = dfixed_const_half((A)) }
 #define dfixed_trunc(A) ((A).full >> 12)
+#define dfixed_frac(A) ((A).full & ((1 << 12) - 1))
 
 static inline u32 dfixed_floor(fixed20_12 A)
 {
-- 
1.7.10