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, <pawel@osciak.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/videobuf2-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         void (*lock)(void *priv);
  49         void (*unlock)(void *priv);
  50 };
  51
  52 struct v4l2_m2m_dev;
  53
  54 struct v4l2_m2m_queue_ctx {
  55 /* private: internal use only */
  56         struct vb2_queue        q;
  57
  58         /* Queue for buffers ready to be processed as soon as this
  59          * instance receives access to the device */
  60         struct list_head        rdy_queue;
  61         spinlock_t              rdy_spinlock;
  62         u8                      num_rdy;
  63 };
  64
  65 struct v4l2_m2m_ctx {
  66 /* private: internal use only */
  67         struct v4l2_m2m_dev             *m2m_dev;
  68
  69         /* Capture (output to memory) queue context */
  70         struct v4l2_m2m_queue_ctx       cap_q_ctx;
  71
  72         /* Output (input from memory) queue context */
  73         struct v4l2_m2m_queue_ctx       out_q_ctx;
  74
  75         /* For device job queue */
  76         struct list_head                queue;
  77         unsigned long                   job_flags;
  78         wait_queue_head_t               finished;
  79
  80         /* Instance private data */
  81         void                            *priv;
  82 };
  83
  84 struct v4l2_m2m_buffer {
  85         struct vb2_buffer       vb;
  86         struct list_head        list;
  87 };
  88
  89 void *v4l2_m2m_get_curr_priv(struct v4l2_m2m_dev *m2m_dev);
  90
  91 struct vb2_queue *v4l2_m2m_get_vq(struct v4l2_m2m_ctx *m2m_ctx,
  92                                        enum v4l2_buf_type type);
  93
  94 void v4l2_m2m_job_finish(struct v4l2_m2m_dev *m2m_dev,
  95                          struct v4l2_m2m_ctx *m2m_ctx);
  96
  97 static inline void
  98 v4l2_m2m_buf_done(struct vb2_buffer *buf, enum vb2_buffer_state state)
  99 {
 100         vb2_buffer_done(buf, state);
 101 }
 102
 103 int v4l2_m2m_reqbufs(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 104                      struct v4l2_requestbuffers *reqbufs);
 105
 106 int v4l2_m2m_querybuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 107                       struct v4l2_buffer *buf);
 108
 109 int v4l2_m2m_qbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 110                   struct v4l2_buffer *buf);
 111 int v4l2_m2m_dqbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 112                    struct v4l2_buffer *buf);
 113
 114 int v4l2_m2m_streamon(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 115                       enum v4l2_buf_type type);
 116 int v4l2_m2m_streamoff(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 117                        enum v4l2_buf_type type);
 118
 119 unsigned int v4l2_m2m_poll(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 120                            struct poll_table_struct *wait);
 121
 122 int v4l2_m2m_mmap(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 123                   struct vm_area_struct *vma);
 124
 125 struct v4l2_m2m_dev *v4l2_m2m_init(struct v4l2_m2m_ops *m2m_ops);
 126 void v4l2_m2m_release(struct v4l2_m2m_dev *m2m_dev);
 127
 128 struct v4l2_m2m_ctx *v4l2_m2m_ctx_init(struct v4l2_m2m_dev *m2m_dev,
 129                 void *drv_priv,
 130                 int (*queue_init)(void *priv, struct vb2_queue *src_vq, struct vb2_queue *dst_vq));
 131
 132 void v4l2_m2m_ctx_release(struct v4l2_m2m_ctx *m2m_ctx);
 133
 134 void v4l2_m2m_buf_queue(struct v4l2_m2m_ctx *m2m_ctx, struct vb2_buffer *vb);
 135
 136 /**
 137  * v4l2_m2m_num_src_bufs_ready() - return the number of source buffers ready for
 138  * use
 139  */
 140 static inline
 141 unsigned int v4l2_m2m_num_src_bufs_ready(struct v4l2_m2m_ctx *m2m_ctx)
 142 {
 143         return m2m_ctx->cap_q_ctx.num_rdy;
 144 }
 145
 146 /**
 147  * v4l2_m2m_num_src_bufs_ready() - return the number of destination buffers
 148  * ready for use
 149  */
 150 static inline
 151 unsigned int v4l2_m2m_num_dst_bufs_ready(struct v4l2_m2m_ctx *m2m_ctx)
 152 {
 153         return m2m_ctx->out_q_ctx.num_rdy;
 154 }
 155
 156 void *v4l2_m2m_next_buf(struct v4l2_m2m_queue_ctx *q_ctx);
 157
 158 /**
 159  * v4l2_m2m_next_src_buf() - return next source buffer from the list of ready
 160  * buffers
 161  */
 162 static inline void *v4l2_m2m_next_src_buf(struct v4l2_m2m_ctx *m2m_ctx)
 163 {
 164         return v4l2_m2m_next_buf(&m2m_ctx->out_q_ctx);
 165 }
 166
 167 /**
 168  * v4l2_m2m_next_dst_buf() - return next destination buffer from the list of
 169  * ready buffers
 170  */
 171 static inline void *v4l2_m2m_next_dst_buf(struct v4l2_m2m_ctx *m2m_ctx)
 172 {
 173         return v4l2_m2m_next_buf(&m2m_ctx->cap_q_ctx);
 174 }
 175
 176 /**
 177  * v4l2_m2m_get_src_vq() - return vb2_queue for source buffers
 178  */
 179 static inline
 180 struct vb2_queue *v4l2_m2m_get_src_vq(struct v4l2_m2m_ctx *m2m_ctx)
 181 {
 182         return &m2m_ctx->out_q_ctx.q;
 183 }
 184
 185 /**
 186  * v4l2_m2m_get_dst_vq() - return vb2_queue for destination buffers
 187  */
 188 static inline
 189 struct vb2_queue *v4l2_m2m_get_dst_vq(struct v4l2_m2m_ctx *m2m_ctx)
 190 {
 191         return &m2m_ctx->cap_q_ctx.q;
 192 }
 193
 194 void *v4l2_m2m_buf_remove(struct v4l2_m2m_queue_ctx *q_ctx);
 195
 196 /**
 197  * v4l2_m2m_src_buf_remove() - take off a source buffer from the list of ready
 198  * buffers and return it
 199  */
 200 static inline void *v4l2_m2m_src_buf_remove(struct v4l2_m2m_ctx *m2m_ctx)
 201 {
 202         return v4l2_m2m_buf_remove(&m2m_ctx->out_q_ctx);
 203 }
 204
 205 /**
 206  * v4l2_m2m_dst_buf_remove() - take off a destination buffer from the list of
 207  * ready buffers and return it
 208  */
 209 static inline void *v4l2_m2m_dst_buf_remove(struct v4l2_m2m_ctx *m2m_ctx)
 210 {
 211         return v4l2_m2m_buf_remove(&m2m_ctx->cap_q_ctx);
 212 }
 213
 214 #endif /* _MEDIA_V4L2_MEM2MEM_H */
 215