xref: /linux/include/media/v4l2-mem2mem.h (revision c0e297dc61f8d4453e07afbea1fa8d0e67cd4a34)
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 	bool			buffered;
64 };
65 
66 struct v4l2_m2m_ctx {
67 	/* optional cap/out vb2 queues lock */
68 	struct mutex			*q_lock;
69 
70 /* private: internal use only */
71 	struct v4l2_m2m_dev		*m2m_dev;
72 
73 	/* Capture (output to memory) queue context */
74 	struct v4l2_m2m_queue_ctx	cap_q_ctx;
75 
76 	/* Output (input from memory) queue context */
77 	struct v4l2_m2m_queue_ctx	out_q_ctx;
78 
79 	/* For device job queue */
80 	struct list_head		queue;
81 	unsigned long			job_flags;
82 	wait_queue_head_t		finished;
83 
84 	/* Instance private data */
85 	void				*priv;
86 };
87 
88 struct v4l2_m2m_buffer {
89 	struct vb2_buffer	vb;
90 	struct list_head	list;
91 };
92 
93 void *v4l2_m2m_get_curr_priv(struct v4l2_m2m_dev *m2m_dev);
94 
95 struct vb2_queue *v4l2_m2m_get_vq(struct v4l2_m2m_ctx *m2m_ctx,
96 				       enum v4l2_buf_type type);
97 
98 void v4l2_m2m_try_schedule(struct v4l2_m2m_ctx *m2m_ctx);
99 
100 void v4l2_m2m_job_finish(struct v4l2_m2m_dev *m2m_dev,
101 			 struct v4l2_m2m_ctx *m2m_ctx);
102 
103 static inline void
104 v4l2_m2m_buf_done(struct vb2_buffer *buf, enum vb2_buffer_state state)
105 {
106 	vb2_buffer_done(buf, state);
107 }
108 
109 int v4l2_m2m_reqbufs(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
110 		     struct v4l2_requestbuffers *reqbufs);
111 
112 int v4l2_m2m_querybuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
113 		      struct v4l2_buffer *buf);
114 
115 int v4l2_m2m_qbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
116 		  struct v4l2_buffer *buf);
117 int v4l2_m2m_dqbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
118 		   struct v4l2_buffer *buf);
119 int v4l2_m2m_prepare_buf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
120 			 struct v4l2_buffer *buf);
121 int v4l2_m2m_create_bufs(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
122 			 struct v4l2_create_buffers *create);
123 
124 int v4l2_m2m_expbuf(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
125 		   struct v4l2_exportbuffer *eb);
126 
127 int v4l2_m2m_streamon(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
128 		      enum v4l2_buf_type type);
129 int v4l2_m2m_streamoff(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
130 		       enum v4l2_buf_type type);
131 
132 unsigned int v4l2_m2m_poll(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
133 			   struct poll_table_struct *wait);
134 
135 int v4l2_m2m_mmap(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
136 		  struct vm_area_struct *vma);
137 
138 struct v4l2_m2m_dev *v4l2_m2m_init(const struct v4l2_m2m_ops *m2m_ops);
139 void v4l2_m2m_release(struct v4l2_m2m_dev *m2m_dev);
140 
141 struct v4l2_m2m_ctx *v4l2_m2m_ctx_init(struct v4l2_m2m_dev *m2m_dev,
142 		void *drv_priv,
143 		int (*queue_init)(void *priv, struct vb2_queue *src_vq, struct vb2_queue *dst_vq));
144 
145 static inline void v4l2_m2m_set_src_buffered(struct v4l2_m2m_ctx *m2m_ctx,
146 					     bool buffered)
147 {
148 	m2m_ctx->out_q_ctx.buffered = buffered;
149 }
150 
151 static inline void v4l2_m2m_set_dst_buffered(struct v4l2_m2m_ctx *m2m_ctx,
152 					     bool buffered)
153 {
154 	m2m_ctx->cap_q_ctx.buffered = buffered;
155 }
156 
157 void v4l2_m2m_ctx_release(struct v4l2_m2m_ctx *m2m_ctx);
158 
159 void v4l2_m2m_buf_queue(struct v4l2_m2m_ctx *m2m_ctx, struct vb2_buffer *vb);
160 
161 /**
162  * v4l2_m2m_num_src_bufs_ready() - return the number of source buffers ready for
163  * use
164  */
165 static inline
166 unsigned int v4l2_m2m_num_src_bufs_ready(struct v4l2_m2m_ctx *m2m_ctx)
167 {
168 	return m2m_ctx->out_q_ctx.num_rdy;
169 }
170 
171 /**
172  * v4l2_m2m_num_src_bufs_ready() - return the number of destination buffers
173  * ready for use
174  */
175 static inline
176 unsigned int v4l2_m2m_num_dst_bufs_ready(struct v4l2_m2m_ctx *m2m_ctx)
177 {
178 	return m2m_ctx->cap_q_ctx.num_rdy;
179 }
180 
181 void *v4l2_m2m_next_buf(struct v4l2_m2m_queue_ctx *q_ctx);
182 
183 /**
184  * v4l2_m2m_next_src_buf() - return next source buffer from the list of ready
185  * buffers
186  */
187 static inline void *v4l2_m2m_next_src_buf(struct v4l2_m2m_ctx *m2m_ctx)
188 {
189 	return v4l2_m2m_next_buf(&m2m_ctx->out_q_ctx);
190 }
191 
192 /**
193  * v4l2_m2m_next_dst_buf() - return next destination buffer from the list of
194  * ready buffers
195  */
196 static inline void *v4l2_m2m_next_dst_buf(struct v4l2_m2m_ctx *m2m_ctx)
197 {
198 	return v4l2_m2m_next_buf(&m2m_ctx->cap_q_ctx);
199 }
200 
201 /**
202  * v4l2_m2m_get_src_vq() - return vb2_queue for source buffers
203  */
204 static inline
205 struct vb2_queue *v4l2_m2m_get_src_vq(struct v4l2_m2m_ctx *m2m_ctx)
206 {
207 	return &m2m_ctx->out_q_ctx.q;
208 }
209 
210 /**
211  * v4l2_m2m_get_dst_vq() - return vb2_queue for destination buffers
212  */
213 static inline
214 struct vb2_queue *v4l2_m2m_get_dst_vq(struct v4l2_m2m_ctx *m2m_ctx)
215 {
216 	return &m2m_ctx->cap_q_ctx.q;
217 }
218 
219 void *v4l2_m2m_buf_remove(struct v4l2_m2m_queue_ctx *q_ctx);
220 
221 /**
222  * v4l2_m2m_src_buf_remove() - take off a source buffer from the list of ready
223  * buffers and return it
224  */
225 static inline void *v4l2_m2m_src_buf_remove(struct v4l2_m2m_ctx *m2m_ctx)
226 {
227 	return v4l2_m2m_buf_remove(&m2m_ctx->out_q_ctx);
228 }
229 
230 /**
231  * v4l2_m2m_dst_buf_remove() - take off a destination buffer from the list of
232  * ready buffers and return it
233  */
234 static inline void *v4l2_m2m_dst_buf_remove(struct v4l2_m2m_ctx *m2m_ctx)
235 {
236 	return v4l2_m2m_buf_remove(&m2m_ctx->cap_q_ctx);
237 }
238 
239 /* v4l2 ioctl helpers */
240 
241 int v4l2_m2m_ioctl_reqbufs(struct file *file, void *priv,
242 				struct v4l2_requestbuffers *rb);
243 int v4l2_m2m_ioctl_create_bufs(struct file *file, void *fh,
244 				struct v4l2_create_buffers *create);
245 int v4l2_m2m_ioctl_querybuf(struct file *file, void *fh,
246 				struct v4l2_buffer *buf);
247 int v4l2_m2m_ioctl_expbuf(struct file *file, void *fh,
248 				struct v4l2_exportbuffer *eb);
249 int v4l2_m2m_ioctl_qbuf(struct file *file, void *fh,
250 				struct v4l2_buffer *buf);
251 int v4l2_m2m_ioctl_dqbuf(struct file *file, void *fh,
252 				struct v4l2_buffer *buf);
253 int v4l2_m2m_ioctl_prepare_buf(struct file *file, void *fh,
254 			       struct v4l2_buffer *buf);
255 int v4l2_m2m_ioctl_streamon(struct file *file, void *fh,
256 				enum v4l2_buf_type type);
257 int v4l2_m2m_ioctl_streamoff(struct file *file, void *fh,
258 				enum v4l2_buf_type type);
259 int v4l2_m2m_fop_mmap(struct file *file, struct vm_area_struct *vma);
260 unsigned int v4l2_m2m_fop_poll(struct file *file, poll_table *wait);
261 
262 #endif /* _MEDIA_V4L2_MEM2MEM_H */
263 
264