[media] v4l2: move dv-timings related code to v4l2-dv-timings.c

v4l2-common.c contained a bunch of dv-timings related functions.
Move that to the new v4l2-dv-timings.c which is a more appropriate
place for them.
There aren't many drivers that do HDTV, so it is a good idea to separate
common code related to that into a module of its own.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
diff --git a/include/media/v4l2-dv-timings.h b/include/media/v4l2-dv-timings.h
index 41075fa..4c7bb54 100644
--- a/include/media/v4l2-dv-timings.h
+++ b/include/media/v4l2-dv-timings.h
@@ -64,4 +64,63 @@
 			      const struct v4l2_dv_timings_cap *cap,
 			      unsigned pclock_delta);
 
+/** v4l_match_dv_timings() - do two timings match?
+  * @measured:	  the measured timings data.
+  * @standard:	  the timings according to the standard.
+  * @pclock_delta: maximum delta in Hz between standard->pixelclock and
+  * 		the measured timings.
+  *
+  * Returns true if the two timings match, returns false otherwise.
+  */
+bool v4l_match_dv_timings(const struct v4l2_dv_timings *measured,
+			  const struct v4l2_dv_timings *standard,
+			  unsigned pclock_delta);
+
+/** v4l2_detect_cvt - detect if the given timings follow the CVT standard
+ * @frame_height - the total height of the frame (including blanking) in lines.
+ * @hfreq - the horizontal frequency in Hz.
+ * @vsync - the height of the vertical sync in lines.
+ * @polarities - the horizontal and vertical polarities (same as struct
+ *		v4l2_bt_timings polarities).
+ * @fmt - the resulting timings.
+ *
+ * This function will attempt to detect if the given values correspond to a
+ * valid CVT format. If so, then it will return true, and fmt will be filled
+ * in with the found CVT timings.
+ */
+bool v4l2_detect_cvt(unsigned frame_height, unsigned hfreq, unsigned vsync,
+		u32 polarities, struct v4l2_dv_timings *fmt);
+
+/** v4l2_detect_gtf - detect if the given timings follow the GTF standard
+ * @frame_height - the total height of the frame (including blanking) in lines.
+ * @hfreq - the horizontal frequency in Hz.
+ * @vsync - the height of the vertical sync in lines.
+ * @polarities - the horizontal and vertical polarities (same as struct
+ *		v4l2_bt_timings polarities).
+ * @aspect - preferred aspect ratio. GTF has no method of determining the
+ *		aspect ratio in order to derive the image width from the
+ *		image height, so it has to be passed explicitly. Usually
+ *		the native screen aspect ratio is used for this. If it
+ *		is not filled in correctly, then 16:9 will be assumed.
+ * @fmt - the resulting timings.
+ *
+ * This function will attempt to detect if the given values correspond to a
+ * valid GTF format. If so, then it will return true, and fmt will be filled
+ * in with the found GTF timings.
+ */
+bool v4l2_detect_gtf(unsigned frame_height, unsigned hfreq, unsigned vsync,
+		u32 polarities, struct v4l2_fract aspect,
+		struct v4l2_dv_timings *fmt);
+
+/** v4l2_calc_aspect_ratio - calculate the aspect ratio based on bytes
+ *	0x15 and 0x16 from the EDID.
+ * @hor_landscape - byte 0x15 from the EDID.
+ * @vert_portrait - byte 0x16 from the EDID.
+ *
+ * Determines the aspect ratio from the EDID.
+ * See VESA Enhanced EDID standard, release A, rev 2, section 3.6.2:
+ * "Horizontal and Vertical Screen Size or Aspect Ratio"
+ */
+struct v4l2_fract v4l2_calc_aspect_ratio(u8 hor_landscape, u8 vert_portrait);
+
 #endif