[media] davinci: vpfe: add v4l2 video driver support

Add a generic video driver functionality to be used by all the vpfe
drivers for davinci SoCs. The functionality includes all the
standard v4l2 interfaces including streaming. The video node
interface can be used both as an input and output node for both
continuous and single shot modes. Also supports dv_presets to include
HD modes, wth support for both user pointer IO and mmap. The buffering
mechanism is based on videobuf2 interface.
Signed-off-by: Manjunath Hadli <manjunath.hadli@ti.com>
Signed-off-by: Lad, Prabhakar <prabhakar.lad@ti.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Sakari Ailus <sakari.ailus@iki.fi>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/staging/media/davinci_vpfe/vpfe_video.h

+/*
+ * Copyright (C) 2012 Texas Instruments Inc
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ *
+ * Contributors:
+ *      Manjunath Hadli <manjunath.hadli@ti.com>
+ *      Prabhakar Lad <prabhakar.lad@ti.com>
+ */
+
+#ifndef _DAVINCI_VPFE_VIDEO_H
+#define _DAVINCI_VPFE_VIDEO_H
+
+#include <media/videobuf2-dma-contig.h>
+
+struct vpfe_device;
+
+/*
+ * struct vpfe_video_operations - VPFE video operations
+ * @queue:	Resume streaming when a buffer is queued. Called on VIDIOC_QBUF
+ *		if there was no buffer previously queued.
+ */
+struct vpfe_video_operations {
+	int(*queue) (struct vpfe_device *vpfe_dev, unsigned long addr);
+};
+
+enum vpfe_pipeline_stream_state {
+	VPFE_PIPELINE_STREAM_STOPPED = 0,
+	VPFE_PIPELINE_STREAM_CONTINUOUS = 1,
+	VPFE_PIPELINE_STREAM_SINGLESHOT = 2,
+};
+
+enum vpfe_video_state {
+	/* indicates that buffer is not queued */
+	VPFE_VIDEO_BUFFER_NOT_QUEUED = 0,
+	/* indicates that buffer is queued */
+	VPFE_VIDEO_BUFFER_QUEUED = 1,
+};
+
+struct vpfe_pipeline {
+	/* media pipeline */
+	struct media_pipeline		*pipe;
+	/* state of the pipeline, continuous,
+	 * single-shot or stopped
+	 */
+	enum vpfe_pipeline_stream_state	state;
+	/* number of active input video entities */
+	unsigned int			input_num;
+	/* number of active output video entities */
+	unsigned int			output_num;
+	/* input video nodes in case of single-shot mode */
+	struct vpfe_video_device	*inputs[10];
+	/* capturing video nodes */
+	struct vpfe_video_device	*outputs[10];
+};
+
+#define to_vpfe_pipeline(__e) \
+	container_of((__e)->pipe, struct vpfe_pipeline, pipe)
+
+#define to_vpfe_video(vdev) \
+	container_of(vdev, struct vpfe_video_device, video_dev)
+
+struct vpfe_cap_buffer {
+	struct vb2_buffer vb;
+	struct list_head list;
+};
+
+struct vpfe_video_device {
+	/* vpfe device */
+	struct vpfe_device			*vpfe_dev;
+	/* video dev */
+	struct video_device			video_dev;
+	/* media pad of video entity */
+	struct media_pad			pad;
+	/* video operations supported by video device */
+	const struct vpfe_video_operations	*ops;
+	/* type of the video buffers used by user */
+	enum v4l2_buf_type			type;
+	/* Indicates id of the field which is being captured */
+	u32					field_id;
+	/* pipeline for which video device is part of */
+	struct vpfe_pipeline			pipe;
+	/* Indicates whether streaming started */
+	u8					started;
+	/* Indicates state of the stream */
+	unsigned int				state;
+	/* current input at the sub device */
+	int					current_input;
+	/*
+	 * This field keeps track of type of buffer exchange mechanism
+	 * user has selected
+	 */
+	enum v4l2_memory			memory;
+	/* Used to keep track of state of the priority */
+	struct v4l2_prio_state			prio;
+	/* number of open instances of the channel */
+	u32					usrs;
+	/* flag to indicate whether decoder is initialized */
+	u8					initialized;
+	/* skip frame count */
+	u8					skip_frame_count;
+	/* skip frame count init value */
+	u8					skip_frame_count_init;
+	/* time per frame for skipping */
+	struct v4l2_fract			timeperframe;
+	/* ptr to currently selected sub device */
+	struct vpfe_ext_subdev_info		*current_ext_subdev;
+	/* Pointer pointing to current vpfe_cap_buffer */
+	struct vpfe_cap_buffer			*cur_frm;
+	/* Pointer pointing to next vpfe_cap_buffer */
+	struct vpfe_cap_buffer			*next_frm;
+	/* Used to store pixel format */
+	struct v4l2_format			fmt;
+	struct vb2_queue			buffer_queue;
+	/* allocator-specific contexts for each plane */
+	struct vb2_alloc_ctx *alloc_ctx;
+	/* Queue of filled frames */
+	struct list_head			dma_queue;
+	spinlock_t				irqlock;
+	/* IRQ lock for DMA queue */
+	spinlock_t				dma_queue_lock;
+	/* lock used to access this structure */
+	struct mutex				lock;
+	/* number of users performing IO */
+	u32					io_usrs;
+	/* Currently selected or default standard */
+	v4l2_std_id				stdid;
+	/*
+	 * offset where second field starts from the starting of the
+	 * buffer for field seperated YCbCr formats
+	 */
+	u32					field_off;
+};
+
+int vpfe_video_is_pipe_ready(struct vpfe_pipeline *pipe);
+void vpfe_video_unregister(struct vpfe_video_device *video);
+int vpfe_video_register(struct vpfe_video_device *video,
+			struct v4l2_device *vdev);
+int vpfe_video_init(struct vpfe_video_device *video, const char *name);
+void vpfe_video_process_buffer_complete(struct vpfe_video_device *video);
+void vpfe_video_schedule_bottom_field(struct vpfe_video_device *video);
+void vpfe_video_schedule_next_buffer(struct vpfe_video_device *video);
+
+#endif		/* _DAVINCI_VPFE_VIDEO_H */