[PATCH v5 1/3] v4l: Add multi-planar API definitions to the V4L2 API

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Multi-planar API is as a backwards-compatible extension of the V4L2 API,
which allows video buffers to consist of one or more planes. Planes are
separate memory buffers; each has its own mapping, backed by usually
separate physical memory buffers.

Many different uses for the multi-planar API are possible, examples
include:
- embedded devices requiring video components to be placed in physically
separate buffers, e.g. for Samsung S3C/S5P SoC series' video codec,
Y and interleaved Cb/Cr components reside in buffers in different
memory banks;
- applications may receive (or choose to store) video data of one video
buffer in separate memory buffers; such data would have to be temporarily
copied together into one buffer before passing it to a V4L2 device;
- applications or drivers may want to pass metadata related to a buffer and
it may not be possible to place it in the same buffer, together with video
data.

Signed-off-by: Pawel Osciak <p.osciak@xxxxxxxxxxx>
Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
Reviewed-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
---
 drivers/media/video/v4l2-ioctl.c |    2 +
 include/linux/videodev2.h        |  126 +++++++++++++++++++++++++++++++++++++-
 2 files changed, 126 insertions(+), 2 deletions(-)

diff --git a/drivers/media/video/v4l2-ioctl.c b/drivers/media/video/v4l2-ioctl.c
index 0eeceae..a830bbd 100644
--- a/drivers/media/video/v4l2-ioctl.c
+++ b/drivers/media/video/v4l2-ioctl.c
@@ -168,6 +168,8 @@ const char *v4l2_type_names[] = {
 	[V4L2_BUF_TYPE_SLICED_VBI_CAPTURE] = "sliced-vbi-cap",
 	[V4L2_BUF_TYPE_SLICED_VBI_OUTPUT]  = "sliced-vbi-out",
 	[V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY] = "vid-out-overlay",
+	[V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE] = "vid-cap-mplane",
+	[V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE] = "vid-out-mplane",
 };
 EXPORT_SYMBOL(v4l2_type_names);
 
diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h
index 047f7e6..0379f07 100644
--- a/include/linux/videodev2.h
+++ b/include/linux/videodev2.h
@@ -70,6 +70,7 @@
  * Moved from videodev.h
  */
 #define VIDEO_MAX_FRAME               32
+#define VIDEO_MAX_PLANES               8
 
 #ifndef __KERNEL__
 
@@ -157,9 +158,23 @@ enum v4l2_buf_type {
 	/* Experimental */
 	V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY = 8,
 #endif
+	V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE = 17,
+	V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE  = 18,
 	V4L2_BUF_TYPE_PRIVATE              = 0x80,
 };
 
+#define V4L2_TYPE_IS_MULTIPLANAR(type)			\
+	((type) == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE	\
+	 || (type) == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE)
+
+#define V4L2_TYPE_IS_OUTPUT(type)				\
+	((type) == V4L2_BUF_TYPE_VIDEO_OUTPUT			\
+	 || (type) == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE		\
+	 || (type) == V4L2_BUF_TYPE_VIDEO_OVERLAY		\
+	 || (type) == V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY	\
+	 || (type) == V4L2_BUF_TYPE_VBI_OUTPUT			\
+	 || (type) == V4L2_BUF_TYPE_SLICED_VBI_OUTPUT)
+
 enum v4l2_tuner_type {
 	V4L2_TUNER_RADIO	     = 1,
 	V4L2_TUNER_ANALOG_TV	     = 2,
@@ -245,6 +260,11 @@ struct v4l2_capability {
 #define V4L2_CAP_HW_FREQ_SEEK		0x00000400  /* Can do hardware frequency seek  */
 #define V4L2_CAP_RDS_OUTPUT		0x00000800  /* Is an RDS encoder */
 
+/* Is a video capture device that supports multiplanar formats */
+#define V4L2_CAP_VIDEO_CAPTURE_MPLANE	0x00001000
+/* Is a video output device that supports multiplanar formats */
+#define V4L2_CAP_VIDEO_OUTPUT_MPLANE	0x00002000
+
 #define V4L2_CAP_TUNER			0x00010000  /* has a tuner */
 #define V4L2_CAP_AUDIO			0x00020000  /* has audio support */
 #define V4L2_CAP_RADIO			0x00040000  /* is a radio device */
@@ -514,6 +534,63 @@ struct v4l2_requestbuffers {
 	__u32			reserved[2];
 };
 
+/**
+ * struct v4l2_plane - plane info for multi-planar buffers
+ * @bytesused:		number of bytes occupied by data in the plane (payload)
+ * @mem_offset:		when memory in the associated struct v4l2_buffer is
+ * 			V4L2_MEMORY_MMAP, equals the offset from the start of
+ * 			the device memory for this plane (or is a "cookie" that
+ * 			should be passed to mmap() called on the video node)
+ * @userptr:		when memory is V4L2_MEMORY_USERPTR, a userspace pointer
+ * 			pointing
+ * 			to this plane
+ * @length:		size of this plane (NOT the payload) in bytes
+ * @data_offset:	offset in plane to the start of data/end of header,
+ * 			if relevant
+ *
+ * Multi-planar buffers consist of one or more planes, e.g. an YCbCr buffer
+ * with two planes can have one plane for Y, and another for interleaved CbCr
+ * components. Each plane can reside in a separate memory buffer, or even in
+ * a completely separate memory node (e.g. in embedded devices).
+ */
+struct v4l2_plane {
+	__u32			bytesused;
+	__u32			length;
+	union {
+		__u32		mem_offset;
+		unsigned long	userptr;
+	} m;
+	__u32			data_offset;
+	__u32			reserved[11];
+};
+
+/**
+ * struct v4l2_buffer - video buffer info
+ * @index:	id number of the buffer
+ * @type:	buffer type (type == *_MPLANE for multiplanar buffers)
+ * @bytesused:	number of bytes occupied by data in the buffer (payload);
+ * 		unused (set to 0) for multiplanar buffers
+ * @flags:	buffer informational flags
+ * @field:	field order of the image in the buffer
+ * @timestamp:	frame timestamp
+ * @timecode:	frame timecode
+ * @sequence:	sequence count of this frame
+ * @memory:	the method, in which the actual video data is passed
+ * @offset:	for non-multiplanar buffers with memory == V4L2_MEMORY_MMAP;
+ * 		offset from the start of the device memory for this plane,
+ * 		(or a "cookie" that should be passed to mmap() as offset)
+ * @userptr:	for non-multiplanar buffers with memory == V4L2_MEMORY_USERPTR;
+ * 		a userspace pointer pointing to this buffer
+ * @planes:	for multiplanar buffers; userspace pointer to the array of plane
+ * 		info structs for this buffer
+ * @length:	size in bytes of the buffer (NOT its payload) for single-plane
+ * 		buffers (when type != *_MPLANE); number of planes (and number
+ * 		of elements in the planes array) for multi-plane buffers
+ * @input:	input number from which the video data has has been captured
+ *
+ * Contains data exchanged by application and driver using one of the Streaming
+ * I/O methods.
+ */
 struct v4l2_buffer {
 	__u32			index;
 	enum v4l2_buf_type      type;
@@ -529,6 +606,7 @@ struct v4l2_buffer {
 	union {
 		__u32           offset;
 		unsigned long   userptr;
+		struct v4l2_plane *planes;
 	} m;
 	__u32			length;
 	__u32			input;
@@ -1613,12 +1691,57 @@ struct v4l2_mpeg_vbi_fmt_ivtv {
  *	A G G R E G A T E   S T R U C T U R E S
  */
 
-/*	Stream data format
+/**
+ * struct v4l2_plane_pix_format - additional, per-plane format definition
+ * @sizeimage:		maximum size in bytes required for data, for which
+ * 			this plane will be used
+ * @bytesperline:	distance in bytes between the leftmost pixels in two
+ * 			adjacent lines
+ */
+struct v4l2_plane_pix_format {
+	__u32		sizeimage;
+	__u16		bytesperline;
+	__u16		reserved[7];
+} __attribute__ ((packed));
+
+/**
+ * struct v4l2_pix_format_mplane - multiplanar format definition
+ * @width:		image width in pixels
+ * @height:		image height in pixels
+ * @pixelformat:	little endian four character code (fourcc)
+ * @field:		field order (for interlaced video)
+ * @colorspace:		supplemental to pixelformat
+ * @plane_fmt:		per-plane information
+ * @num_planes:		number of planes for this format and number of valid
+ * 			elements in plane_fmt array
+ */
+struct v4l2_pix_format_mplane {
+	__u32				width;
+	__u32				height;
+	__u32				pixelformat;
+	enum v4l2_field			field;
+	enum v4l2_colorspace		colorspace;
+
+	struct v4l2_plane_pix_format	plane_fmt[VIDEO_MAX_PLANES];
+	__u8				num_planes;
+	__u8				reserved[11];
+} __attribute__ ((packed));
+
+/**
+ * struct v4l2_format - stream data format
+ * @type:	type of the data stream
+ * @pix:	definition of an image format
+ * @pix_mp:	definition of a multiplanar image format
+ * @win:	definition of an overlaid image
+ * @vbi:	raw VBI capture or output parameters
+ * @sliced:	sliced VBI capture or output parameters
+ * @raw_data:	placeholder for future extensions and custom formats
  */
 struct v4l2_format {
 	enum v4l2_buf_type type;
 	union {
 		struct v4l2_pix_format		pix;     /* V4L2_BUF_TYPE_VIDEO_CAPTURE */
+		struct v4l2_pix_format_mplane	pix_mp;  /* V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE */
 		struct v4l2_window		win;     /* V4L2_BUF_TYPE_VIDEO_OVERLAY */
 		struct v4l2_vbi_format		vbi;     /* V4L2_BUF_TYPE_VBI_CAPTURE */
 		struct v4l2_sliced_vbi_format	sliced;  /* V4L2_BUF_TYPE_SLICED_VBI_CAPTURE */
@@ -1626,7 +1749,6 @@ struct v4l2_format {
 	} fmt;
 };
 
-
 /*	Stream type-dependent parameters
  */
 struct v4l2_streamparm {
-- 
1.7.1.569.g6f426

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