[PATCH v2 1/6] [media] v4l: add blend modes controls

[Jacob Chen]

At peresent, we don't have a control for Compositing and Blend.
All drivers are just doing copies while actually many hardwares
supports more functions.

So Adding V4L2 controls for Compositing and Blend, used for for
composting streams.

The values are based on porter duff operations.
Defined in below links.
https://developer.xamarin.com/api/type/Android.Graphics.PorterDuff+Mode/

Signed-off-by: Jacob Chen <jacob-chen at iotwrt.com>
Suggested-by: Nicolas Dufresne <nicolas at ndufresne.ca>
---
 drivers/media/v4l2-core/v4l2-ctrls.c | 19 +++++++++++++++++++
 include/uapi/linux/v4l2-controls.h   | 18 +++++++++++++++++-
 2 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
index b9e08e3..8a235fd 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -216,6 +216,21 @@ const char * const *v4l2_ctrl_get_menu(u32 id)
 		"Private Packet, IVTV Format",
 		NULL
 	};
+	static const char * const blend_modes[] = {
+		"Source",
+		"Source Top",
+		"Source In",
+		"Source Out",
+		"Source Over",
+		"Destination",
+		"Destination Top",
+		"Destination In",
+		"Destination Out",
+		"Destination Over",
+		"Add",
+		"Clear",
+		NULL
+	};
 	static const char * const camera_power_line_frequency[] = {
 		"Disabled",
 		"50 Hz",
@@ -522,6 +537,8 @@ const char * const *v4l2_ctrl_get_menu(u32 id)
 		return camera_exposure_metering;
 	case V4L2_CID_AUTO_FOCUS_RANGE:
 		return camera_auto_focus_range;
+	case V4L2_CID_BLEND:
+		return blend_modes;
 	case V4L2_CID_COLORFX:
 		return colorfx;
 	case V4L2_CID_AUTO_N_PRESET_WHITE_BALANCE:
@@ -655,6 +672,7 @@ const char *v4l2_ctrl_get_name(u32 id)
 	case V4L2_CID_MIN_BUFFERS_FOR_OUTPUT:	return "Min Number of Output Buffers";
 	case V4L2_CID_ALPHA_COMPONENT:		return "Alpha Component";
 	case V4L2_CID_COLORFX_CBCR:		return "Color Effects, CbCr";
+	case V4L2_CID_BLEND:			return "Compositing and Blend Modes";
 
 	/* Codec controls */
 	/* The MPEG controls are applicable to all codec controls
@@ -1033,6 +1051,7 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
 	case V4L2_CID_MPEG_STREAM_VBI_FMT:
 	case V4L2_CID_EXPOSURE_AUTO:
 	case V4L2_CID_AUTO_FOCUS_RANGE:
+	case V4L2_CID_BLEND:
 	case V4L2_CID_COLORFX:
 	case V4L2_CID_AUTO_N_PRESET_WHITE_BALANCE:
 	case V4L2_CID_TUNE_PREEMPHASIS:
diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
index 0d2e1e0..019fdca 100644
--- a/include/uapi/linux/v4l2-controls.h
+++ b/include/uapi/linux/v4l2-controls.h
@@ -140,8 +140,24 @@ enum v4l2_colorfx {
 #define V4L2_CID_ALPHA_COMPONENT		(V4L2_CID_BASE+41)
 #define V4L2_CID_COLORFX_CBCR			(V4L2_CID_BASE+42)
 
+#define V4L2_CID_BLEND				(V4L2_CID_BASE+43)
+enum v4l2_blend_mode {
+	V4L2_BLEND_SRC				= 0,
+	V4L2_BLEND_SRCATOP			= 1,
+	V4L2_BLEND_SRCIN			= 2,
+	V4L2_BLEND_SRCOUT			= 3,
+	V4L2_BLEND_SRCOVER			= 4,
+	V4L2_BLEND_DST				= 5,
+	V4L2_BLEND_DSTATOP			= 6,
+	V4L2_BLEND_DSTIN			= 7,
+	V4L2_BLEND_DSTOUT			= 8,
+	V4L2_BLEND_DSTOVER			= 9,
+	V4L2_BLEND_ADD				= 10,
+	V4L2_BLEND_CLEAR			= 11,
+};
+
 /* last CID + 1 */
-#define V4L2_CID_LASTP1                         (V4L2_CID_BASE+43)
+#define V4L2_CID_LASTP1                         (V4L2_CID_BASE+44)
 
 /* USER-class private control IDs */
 
-- 
2.7.4