/*
* Memory-to-memory device framework for Video for Linux 2.
*
* Helper functions for devices that use memory buffers for both source
* and destination.
*
* Copyright (c) 2009 Samsung Electronics Co., Ltd.
* Pawel Osciak, <[email protected]>
* Marek Szyprowski, <[email protected]>
*
* 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; either version 2 of the
* License, or (at your option) any later version
*/

#ifndef _MEDIA_V4L2_MEM2MEM_H
#define _MEDIA_V4L2_MEM2MEM_H

#include <media/videobuf2-core.h>

/**
* struct v4l2_m2m_ops - mem-to-mem device driver callbacks
* @device_run: required. Begin the actual job (transaction) inside this
* callback.
* The job does NOT have to end before this callback returns
* (and it will be the usual case). When the job finishes,
* v4l2_m2m_job_finish() has to be called.
* @job_ready: optional. Should return 0 if the driver does not have a job
* fully prepared to run yet (i.e. it will not be able to finish a
* transaction without sleeping). If not provided, it will be
* assumed that one source and one destination buffer are all
* that is required for the driver to perform one full transaction.
* This method may not sleep.
* @job_abort: required. Informs the driver that it has to abort the currently
* running transaction as soon as possible (i.e. as soon as it can
* stop the device safely; e.g. in the next interrupt handler),
* even if the transaction would not have been finished by then.
* After the driver performs the necessary steps, it has to call
* v4l2_m2m_job_finish() (as if the transaction ended normally).
* This function does not have to (and will usually not) wait
* until the device enters a state when it can be stopped.
*/
struct v4l2_m2m_ops {
void (*device_run)(void *priv);
int (*job_ready)(void *priv);
void (*job_abort)(void *priv);
void (*lock)(void *priv);
void (*unlock)(void *priv);
};

struct v4l2_m2m_dev;

struct v4l2_m2m_queue_ctx {
/* private: internal use only */
struct vb2_queue q;

/* Queue for buffers ready to be processed as soon as this
* instance receives access to the device */
struct list_head rdy_queue;
spinlock_t rdy_spinlock;
u8 num_rdy;
bool buffered;
};

struct v4l2_m2m_ctx {
/* private: internal use only */
struct v4l2_m2m_dev *m2m_dev;

/* Capture (output to memory) queue context */
struct v4l2_m2m_queue_ctx cap_q_ctx;

/* Output (input from memory) queue context */
struct v4l2_m2m_queue_ctx out_q_ctx;

/* For device job queue */
struct list_head queue;
unsigned long job_flags;
wait_queue_head_t finished;

/* Instance private data */
void *priv;
};

struct v4l2_m2m_buffer {
struct vb2_buffer vb;
struct list_head list;
};

void *v4l2_m2m_get_curr_priv(struct v4l2_m2m_dev *m2m_dev);

struct vb2_queue *v4l2_m2m_get_vq(struct v4l2_m2m_ctx *m2m_ctx,
enum v4l2_buf_type type);

void v4l2_m2m_job_finish(struct v4l2_m2m_dev *m2m_dev,
struct v4l2_m2m_ctx *m2m_ctx);

static inline void
v4l2_m2m_buf_done(struct vb2_buffer *buf, enum vb2_buffer_state state)
{
vb2_buffer_done(buf, state);
}

int v4l2_m2m_reqbufs(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
struct v4l2_requestbuffers *reqbufs);

int v4l2_m2m_querybuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
struct v4l2_buffer *buf);

int v4l2_m2m_qbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
struct v4l2_buffer *buf);
int v4l2_m2m_dqbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
struct v4l2_buffer *buf);
int v4l2_m2m_create_bufs(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
struct v4l2_create_buffers *create);

int v4l2_m2m_expbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
struct v4l2_exportbuffer *eb);

int v4l2_m2m_streamon(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
enum v4l2_buf_type type);
int v4l2_m2m_streamoff(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
enum v4l2_buf_type type);

unsigned int v4l2_m2m_poll(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
struct poll_table_struct *wait);

int v4l2_m2m_mmap(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
struct vm_area_struct *vma);

struct v4l2_m2m_dev *v4l2_m2m_init(const struct v4l2_m2m_ops *m2m_ops);
void v4l2_m2m_release(struct v4l2_m2m_dev *m2m_dev);

struct v4l2_m2m_ctx *v4l2_m2m_ctx_init(struct v4l2_m2m_dev *m2m_dev,
void *drv_priv,
int (*queue_init)(void *priv, struct vb2_queue *src_vq, struct vb2_queue *dst_vq));

static inline void v4l2_m2m_set_src_buffered(struct v4l2_m2m_ctx *m2m_ctx,
bool buffered)
{
m2m_ctx->out_q_ctx.buffered = buffered;
}

static inline void v4l2_m2m_set_dst_buffered(struct v4l2_m2m_ctx *m2m_ctx,
bool buffered)
{
m2m_ctx->cap_q_ctx.buffered = buffered;
}

void v4l2_m2m_ctx_release(struct v4l2_m2m_ctx *m2m_ctx);

void v4l2_m2m_buf_queue(struct v4l2_m2m_ctx *m2m_ctx, struct vb2_buffer *vb);

/**
* v4l2_m2m_num_src_bufs_ready() - return the number of source buffers ready for
* use
*/
static inline
unsigned int v4l2_m2m_num_src_bufs_ready(struct v4l2_m2m_ctx *m2m_ctx)
{
return m2m_ctx->out_q_ctx.num_rdy;
}

/**
* v4l2_m2m_num_src_bufs_ready() - return the number of destination buffers
* ready for use
*/
static inline
unsigned int v4l2_m2m_num_dst_bufs_ready(struct v4l2_m2m_ctx *m2m_ctx)
{
return m2m_ctx->cap_q_ctx.num_rdy;
}

void *v4l2_m2m_next_buf(struct v4l2_m2m_queue_ctx *q_ctx);

/**
* v4l2_m2m_next_src_buf() - return next source buffer from the list of ready
* buffers
*/
static inline void *v4l2_m2m_next_src_buf(struct v4l2_m2m_ctx *m2m_ctx)
{
return v4l2_m2m_next_buf(&m2m_ctx->out_q_ctx);
}

/**
* v4l2_m2m_next_dst_buf() - return next destination buffer from the list of
* ready buffers
*/
static inline void *v4l2_m2m_next_dst_buf(struct v4l2_m2m_ctx *m2m_ctx)
{
return v4l2_m2m_next_buf(&m2m_ctx->cap_q_ctx);
}

/**
* v4l2_m2m_get_src_vq() - return vb2_queue for source buffers
*/
static inline
struct vb2_queue *v4l2_m2m_get_src_vq(struct v4l2_m2m_ctx *m2m_ctx)
{
return &m2m_ctx->out_q_ctx.q;
}

/**
* v4l2_m2m_get_dst_vq() - return vb2_queue for destination buffers
*/
static inline
struct vb2_queue *v4l2_m2m_get_dst_vq(struct v4l2_m2m_ctx *m2m_ctx)
{
return &m2m_ctx->cap_q_ctx.q;
}

void *v4l2_m2m_buf_remove(struct v4l2_m2m_queue_ctx *q_ctx);

/**
* v4l2_m2m_src_buf_remove() - take off a source buffer from the list of ready
* buffers and return it
*/
static inline void *v4l2_m2m_src_buf_remove(struct v4l2_m2m_ctx *m2m_ctx)
{
return v4l2_m2m_buf_remove(&m2m_ctx->out_q_ctx);
}

/**
* v4l2_m2m_dst_buf_remove() - take off a destination buffer from the list of
* ready buffers and return it
*/
static inline void *v4l2_m2m_dst_buf_remove(struct v4l2_m2m_ctx *m2m_ctx)
{
return v4l2_m2m_buf_remove(&m2m_ctx->cap_q_ctx);
}

#endif /* _MEDIA_V4L2_MEM2MEM_H */