1/**
2 * \file include/pcm_ioplug.h
3 * \brief External I/O-Plugin SDK
4 * \author Takashi Iwai <tiwai@suse.de>
5 * \date 2005
6 *
7 * External I/O-Plugin SDK
8 */
9
10/*
11 * ALSA external PCM plugin SDK
12 *
13 * Copyright (c) 2005 Takashi Iwai <tiwai@suse.de>
14 *
15 *   This library is free software; you can redistribute it and/or modify
16 *   it under the terms of the GNU Lesser General Public License as
17 *   published by the Free Software Foundation; either version 2.1 of
18 *   the License, or (at your option) any later version.
19 *
20 *   This program is distributed in the hope that it will be useful,
21 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
22 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
23 *   GNU Lesser General Public License for more details.
24 *
25 *   You should have received a copy of the GNU Lesser General Public
26 *   License along with this library; if not, write to the Free Software
27 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
28 *
29 */
30
31#ifndef __ALSA_PCM_IOPLUG_H
32#define __ALSA_PCM_IOPLUG_H
33
34/**
35 * \defgroup PCM_IOPlug External I/O plugin SDK
36 * \ingroup Plugin_SDK
37 * See the \ref pcm page for more details.
38 * \{
39 */
40
41/** hw constraints for ioplug */
42enum {
43	SND_PCM_IOPLUG_HW_ACCESS = 0,	/**< access type */
44	SND_PCM_IOPLUG_HW_FORMAT,	/**< format */
45	SND_PCM_IOPLUG_HW_CHANNELS,	/**< channels */
46	SND_PCM_IOPLUG_HW_RATE,		/**< rate */
47	SND_PCM_IOPLUG_HW_PERIOD_BYTES,	/**< period bytes */
48	SND_PCM_IOPLUG_HW_BUFFER_BYTES,	/**< buffer bytes */
49	SND_PCM_IOPLUG_HW_PERIODS,	/**< number of periods */
50	SND_PCM_IOPLUG_HW_PARAMS	/**< max number of hw constraints */
51};
52
53/** I/O plugin handle */
54typedef struct snd_pcm_ioplug snd_pcm_ioplug_t;
55/** Callback table of ioplug */
56typedef struct snd_pcm_ioplug_callback snd_pcm_ioplug_callback_t;
57
58/*
59 * bit flags for additional conditions
60 */
61#define SND_PCM_IOPLUG_FLAG_LISTED	(1<<0)		/**< list up this PCM */
62#define SND_PCM_IOPLUG_FLAG_MONOTONIC	(1<<1)		/**< monotonic timestamps */
63
64/*
65 * Protocol version
66 */
67#define SND_PCM_IOPLUG_VERSION_MAJOR	1	/**< Protocol major version */
68#define SND_PCM_IOPLUG_VERSION_MINOR	0	/**< Protocol minor version */
69#define SND_PCM_IOPLUG_VERSION_TINY	1	/**< Protocol tiny version */
70/**
71 * IO-plugin protocol version
72 */
73#define SND_PCM_IOPLUG_VERSION		((SND_PCM_IOPLUG_VERSION_MAJOR<<16) |\
74					 (SND_PCM_IOPLUG_VERSION_MINOR<<8) |\
75					 (SND_PCM_IOPLUG_VERSION_TINY))
76
77/** Handle of ioplug */
78struct snd_pcm_ioplug {
79	/**
80	 * protocol version; #SND_PCM_IOPLUG_VERSION must be filled here
81	 * before calling #snd_pcm_ioplug_create()
82	 */
83	unsigned int version;
84	/**
85	 * name of this plugin; must be filled before calling #snd_pcm_ioplug_create()
86	 */
87	const char *name;
88	unsigned int flags;	/**< SND_PCM_IOPLUG_FLAG_XXX */
89	int poll_fd;		/**< poll file descriptor */
90	unsigned int poll_events;	/**< poll events */
91	unsigned int mmap_rw;		/**< pseudo mmap mode */
92	/**
93	 * callbacks of this plugin; must be filled before calling #snd_pcm_ioplug_create()
94	 */
95	const snd_pcm_ioplug_callback_t *callback;
96	/**
97	 * private data, which can be used freely in the driver callbacks
98	 */
99	void *private_data;
100	/**
101	 * PCM handle filled by #snd_pcm_extplug_create()
102	 */
103	snd_pcm_t *pcm;
104
105	snd_pcm_stream_t stream;	/**< stream direcion; read-only */
106	snd_pcm_state_t state;		/**< current PCM state; read-only */
107	volatile snd_pcm_uframes_t appl_ptr;	/**< application pointer; read-only */
108	volatile snd_pcm_uframes_t hw_ptr;	/**< hw pointer; read-only */
109	int nonblock;			/**< non-block mode; read-only */
110
111	snd_pcm_access_t access;	/**< access type; filled after hw_params is called */
112	snd_pcm_format_t format;	/**< PCM format; filled after hw_params is called */
113	unsigned int channels;		/**< number of channels; filled after hw_params is called */
114	unsigned int rate;		/**< rate; filled after hw_params is called */
115	snd_pcm_uframes_t period_size;	/**< period size; filled after hw_params is called */
116	snd_pcm_uframes_t buffer_size;	/**< buffer size; filled after hw_params is called */
117};
118
119/** Callback table of ioplug */
120struct snd_pcm_ioplug_callback {
121	/**
122	 * start the PCM; required
123	 */
124	int (*start)(snd_pcm_ioplug_t *io);
125	/**
126	 * stop the PCM; required
127	 */
128	int (*stop)(snd_pcm_ioplug_t *io);
129	/**
130	 * get the current DMA position; required
131	 */
132	snd_pcm_sframes_t (*pointer)(snd_pcm_ioplug_t *io);
133	/**
134	 * transfer the data; optional
135	 */
136	snd_pcm_sframes_t (*transfer)(snd_pcm_ioplug_t *io,
137				      const snd_pcm_channel_area_t *areas,
138				      snd_pcm_uframes_t offset,
139				      snd_pcm_uframes_t size);
140	/**
141	 * close the PCM; optional
142	 */
143	int (*close)(snd_pcm_ioplug_t *io);
144	/**
145	 * hw_params; optional
146	 */
147	int (*hw_params)(snd_pcm_ioplug_t *io, snd_pcm_hw_params_t *params);
148	/**
149	 * hw_free; optional
150	 */
151	int (*hw_free)(snd_pcm_ioplug_t *io);
152	/**
153	 * sw_params; optional
154	 */
155	int (*sw_params)(snd_pcm_ioplug_t *io, snd_pcm_sw_params_t *params);
156	/**
157	 * prepare; optional
158	 */
159	int (*prepare)(snd_pcm_ioplug_t *io);
160	/**
161	 * drain; optional
162	 */
163	int (*drain)(snd_pcm_ioplug_t *io);
164	/**
165	 * toggle pause; optional
166	 */
167	int (*pause)(snd_pcm_ioplug_t *io, int enable);
168	/**
169	 * resume; optional
170	 */
171	int (*resume)(snd_pcm_ioplug_t *io);
172	/**
173	 * poll descriptors count; optional
174	 */
175	int (*poll_descriptors_count)(snd_pcm_ioplug_t *io);
176	/**
177	 * poll descriptors; optional
178	 */
179	int (*poll_descriptors)(snd_pcm_ioplug_t *io, struct pollfd *pfd, unsigned int space);
180	/**
181	 * mangle poll events; optional
182	 */
183	int (*poll_revents)(snd_pcm_ioplug_t *io, struct pollfd *pfd, unsigned int nfds, unsigned short *revents);
184	/**
185	 * dump; optional
186	 */
187	void (*dump)(snd_pcm_ioplug_t *io, snd_output_t *out);
188	/**
189	 * get the delay for the running PCM; optional
190	 */
191	int (*delay)(snd_pcm_ioplug_t *io, snd_pcm_sframes_t *delayp);
192};
193
194
195int snd_pcm_ioplug_create(snd_pcm_ioplug_t *io, const char *name,
196			  snd_pcm_stream_t stream, int mode);
197int snd_pcm_ioplug_delete(snd_pcm_ioplug_t *io);
198
199/* update poll_fd and mmap_rw */
200int snd_pcm_ioplug_reinit_status(snd_pcm_ioplug_t *ioplug);
201
202/* get a mmap area (for mmap_rw only) */
203const snd_pcm_channel_area_t *snd_pcm_ioplug_mmap_areas(snd_pcm_ioplug_t *ioplug);
204
205/* clear hw_parameter setting */
206void snd_pcm_ioplug_params_reset(snd_pcm_ioplug_t *io);
207
208/* hw_parameter setting */
209int snd_pcm_ioplug_set_param_minmax(snd_pcm_ioplug_t *io, int type, unsigned int min, unsigned int max);
210int snd_pcm_ioplug_set_param_list(snd_pcm_ioplug_t *io, int type, unsigned int num_list, const unsigned int *list);
211
212/* change PCM status */
213int snd_pcm_ioplug_set_state(snd_pcm_ioplug_t *ioplug, snd_pcm_state_t state);
214
215/** \} */
216
217#endif /* __ALSA_PCM_IOPLUG_H */
218