drm: fixed: Add dfixed_frac

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

Signed-off-by: Robert Morell <[email protected]>
Signed-off-by: Olof Johansson <[email protected]>
Signed-off-by: Thierry Reding <[email protected]>
Signed-off-by: Dave Airlie <[email protected]>

diff --git a/include/drm/drm_fixed.h b/include/drm/drm_fixed.h
index 4a08a664ff1f243fd14cdc094215627e7a626605..0ead502e17d27638fef2bb7df81d9118967b2010 100644 (file)
--- 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)
 {