include/media/v4l2-mem2mem.h

   1 /*
   2  * Memory-to-memory device framework for Video for Linux 2.
   3  *
   4  * Helper functions for devices that use memory buffers for both source
   5  * and destination.
   6  *
   7  * Copyright (c) 2009 Samsung Electronics Co., Ltd.
   8  * Pawel Osciak, <p.osciak@samsung.com>
   9  * Marek Szyprowski, <m.szyprowski@samsung.com>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by the
  13  * Free Software Foundation; either version 2 of the
  14  * License, or (at your option) any later version
  15  */
  16
  17 #ifndef _MEDIA_V4L2_MEM2MEM_H
  18 #define _MEDIA_V4L2_MEM2MEM_H
  19
  20 #include <media/videobuf-core.h>
  21
  22 /**
  23  * struct v4l2_m2m_ops - mem-to-mem device driver callbacks
  24  * @device_run: required. Begin the actual job (transaction) inside this
  25  *              callback.
  26  *              The job does NOT have to end before this callback returns
  27  *              (and it will be the usual case). When the job finishes,
  28  *              v4l2_m2m_job_finish() has to be called.
  29  * @job_ready:  optional. Should return 0 if the driver does not have a job
  30  *              fully prepared to run yet (i.e. it will not be able to finish a
  31  *              transaction without sleeping). If not provided, it will be
  32  *              assumed that one source and one destination buffer are all
  33  *              that is required for the driver to perform one full transaction.
  34  *              This method may not sleep.
  35  * @job_abort:  required. Informs the driver that it has to abort the currently
  36  *              running transaction as soon as possible (i.e. as soon as it can
  37  *              stop the device safely; e.g. in the next interrupt handler),
  38  *              even if the transaction would not have been finished by then.
  39  *              After the driver performs the necessary steps, it has to call
  40  *              v4l2_m2m_job_finish() (as if the transaction ended normally).
  41  *              This function does not have to (and will usually not) wait
  42  *              until the device enters a state when it can be stopped.
  43  */
  44 struct v4l2_m2m_ops {
  45         void (*device_run)(void *priv);
  46         int (*job_ready)(void *priv);
  47         void (*job_abort)(void *priv);
  48 };
  49
  50 struct v4l2_m2m_dev;
  51
  52 struct v4l2_m2m_queue_ctx {
  53 /* private: internal use only */
  54         struct videobuf_queue   q;
  55
  56         /* Queue for buffers ready to be processed as soon as this
  57          * instance receives access to the device */
  58         struct list_head        rdy_queue;
  59         u8                      num_rdy;
  60 };
  61
  62 struct v4l2_m2m_ctx {
  63 /* private: internal use only */
  64         struct v4l2_m2m_dev             *m2m_dev;
  65
  66         /* Capture (output to memory) queue context */
  67         struct v4l2_m2m_queue_ctx       cap_q_ctx;
  68
  69         /* Output (input from memory) queue context */
  70         struct v4l2_m2m_queue_ctx       out_q_ctx;
  71
  72         /* For device job queue */
  73         struct list_head                queue;
  74         unsigned long                   job_flags;
  75
  76         /* Instance private data */
  77         void                            *priv;
  78 };
  79
  80 void *v4l2_m2m_get_curr_priv(struct v4l2_m2m_dev *m2m_dev);
  81
  82 struct videobuf_queue *v4l2_m2m_get_vq(struct v4l2_m2m_ctx *m2m_ctx,
  83                                        enum v4l2_buf_type type);
  84
  85 void v4l2_m2m_job_finish(struct v4l2_m2m_dev *m2m_dev,
  86                          struct v4l2_m2m_ctx *m2m_ctx);
  87
  88 int v4l2_m2m_reqbufs(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
  89                      struct v4l2_requestbuffers *reqbufs);
  90
  91 int v4l2_m2m_querybuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
  92                       struct v4l2_buffer *buf);
  93
  94 int v4l2_m2m_qbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
  95                   struct v4l2_buffer *buf);
  96 int v4l2_m2m_dqbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
  97                    struct v4l2_buffer *buf);
  98
  99 int v4l2_m2m_streamon(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 100                       enum v4l2_buf_type type);
 101 int v4l2_m2m_streamoff(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 102                        enum v4l2_buf_type type);
 103
 104 unsigned int v4l2_m2m_poll(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 105                            struct poll_table_struct *wait);
 106
 107 int v4l2_m2m_mmap(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 108                   struct vm_area_struct *vma);
 109
 110 struct v4l2_m2m_dev *v4l2_m2m_init(struct v4l2_m2m_ops *m2m_ops);
 111 void v4l2_m2m_release(struct v4l2_m2m_dev *m2m_dev);
 112
 113 struct v4l2_m2m_ctx *v4l2_m2m_ctx_init(void *priv, struct v4l2_m2m_dev *m2m_dev,
 114                         void (*vq_init)(void *priv, struct videobuf_queue *,
 115                                         enum v4l2_buf_type));
 116 void v4l2_m2m_ctx_release(struct v4l2_m2m_ctx *m2m_ctx);
 117
 118 void v4l2_m2m_buf_queue(struct v4l2_m2m_ctx *m2m_ctx, struct videobuf_queue *vq,
 119                         struct videobuf_buffer *vb);
 120
 121 /**
 122  * v4l2_m2m_num_src_bufs_ready() - return the number of source buffers ready for
 123  * use
 124  */
 125 static inline
 126 unsigned int v4l2_m2m_num_src_bufs_ready(struct v4l2_m2m_ctx *m2m_ctx)
 127 {
 128         return m2m_ctx->cap_q_ctx.num_rdy;
 129 }
 130
 131 /**
 132  * v4l2_m2m_num_src_bufs_ready() - return the number of destination buffers
 133  * ready for use
 134  */
 135 static inline
 136 unsigned int v4l2_m2m_num_dst_bufs_ready(struct v4l2_m2m_ctx *m2m_ctx)
 137 {
 138         return m2m_ctx->out_q_ctx.num_rdy;
 139 }
 140
 141 void *v4l2_m2m_next_buf(struct v4l2_m2m_ctx *m2m_ctx, enum v4l2_buf_type type);
 142
 143 /**
 144  * v4l2_m2m_next_src_buf() - return next source buffer from the list of ready
 145  * buffers
 146  */
 147 static inline void *v4l2_m2m_next_src_buf(struct v4l2_m2m_ctx *m2m_ctx)
 148 {
 149         return v4l2_m2m_next_buf(m2m_ctx, V4L2_BUF_TYPE_VIDEO_OUTPUT);
 150 }
 151
 152 /**
 153  * v4l2_m2m_next_dst_buf() - return next destination buffer from the list of
 154  * ready buffers
 155  */
 156 static inline void *v4l2_m2m_next_dst_buf(struct v4l2_m2m_ctx *m2m_ctx)
 157 {
 158         return v4l2_m2m_next_buf(m2m_ctx, V4L2_BUF_TYPE_VIDEO_CAPTURE);
 159 }
 160
 161 /**
 162  * v4l2_m2m_get_src_vq() - return videobuf_queue for source buffers
 163  */
 164 static inline
 165 struct videobuf_queue *v4l2_m2m_get_src_vq(struct v4l2_m2m_ctx *m2m_ctx)
 166 {
 167         return v4l2_m2m_get_vq(m2m_ctx, V4L2_BUF_TYPE_VIDEO_OUTPUT);
 168 }
 169
 170 /**
 171  * v4l2_m2m_get_dst_vq() - return videobuf_queue for destination buffers
 172  */
 173 static inline
 174 struct videobuf_queue *v4l2_m2m_get_dst_vq(struct v4l2_m2m_ctx *m2m_ctx)
 175 {
 176         return v4l2_m2m_get_vq(m2m_ctx, V4L2_BUF_TYPE_VIDEO_CAPTURE);
 177 }
 178
 179 void *v4l2_m2m_buf_remove(struct v4l2_m2m_ctx *m2m_ctx,
 180                           enum v4l2_buf_type type);
 181
 182 /**
 183  * v4l2_m2m_src_buf_remove() - take off a source buffer from the list of ready
 184  * buffers and return it
 185  */
 186 static inline void *v4l2_m2m_src_buf_remove(struct v4l2_m2m_ctx *m2m_ctx)
 187 {
 188         return v4l2_m2m_buf_remove(m2m_ctx, V4L2_BUF_TYPE_VIDEO_OUTPUT);
 189 }
 190
 191 /**
 192  * v4l2_m2m_dst_buf_remove() - take off a destination buffer from the list of
 193  * ready buffers and return it
 194  */
 195 static inline void *v4l2_m2m_dst_buf_remove(struct v4l2_m2m_ctx *m2m_ctx)
 196 {
 197         return v4l2_m2m_buf_remove(m2m_ctx, V4L2_BUF_TYPE_VIDEO_CAPTURE);
 198 }
 199
 200 #endif /* _MEDIA_V4L2_MEM2MEM_H */
 201