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
63/*
64 * Protocol version
65 */
66#define SND_PCM_IOPLUG_VERSION_MAJOR	1	/**< Protocol major version */
67#define SND_PCM_IOPLUG_VERSION_MINOR	0	/**< Protocol minor version */
68#define SND_PCM_IOPLUG_VERSION_TINY	1	/**< Protocol tiny version */
69/**
70 * IO-plugin protocol version
71 */
72#define SND_PCM_IOPLUG_VERSION		((SND_PCM_IOPLUG_VERSION_MAJOR<<16) |\
73					 (SND_PCM_IOPLUG_VERSION_MINOR<<8) |\
74					 (SND_PCM_IOPLUG_VERSION_TINY))
75
76/** Handle of ioplug */
77struct snd_pcm_ioplug {
78	/**
79	 * protocol version; #SND_PCM_IOPLUG_VERSION must be filled here
80	 * before calling #snd_pcm_ioplug_create()
81	 */
82	unsigned int version;
83	/**
84	 * name of this plugin; must be filled before calling #snd_pcm_ioplug_create()
85	 */
86	const char *name;
87	unsigned int flags;	/**< SND_PCM_IOPLUG_FLAG_XXX */
88	int poll_fd;		/**< poll file descriptor */
89	unsigned int poll_events;	/**< poll events */
90	unsigned int mmap_rw;		/**< pseudo mmap mode */
91	/**
92	 * callbacks of this plugin; must be filled before calling #snd_pcm_ioplug_create()
93	 */
94	const snd_pcm_ioplug_callback_t *callback;
95	/**
96	 * private data, which can be used freely in the driver callbacks
97	 */
98	void *private_data;
99	/**
100	 * PCM handle filled by #snd_pcm_extplug_create()
101	 */
102	snd_pcm_t *pcm;
103
104	snd_pcm_stream_t stream;	/**< stream direcion; read-only */
105	snd_pcm_state_t state;		/**< current PCM state; read-only */
106	volatile snd_pcm_uframes_t appl_ptr;	/**< application pointer; read-only */
107	volatile snd_pcm_uframes_t hw_ptr;	/**< hw pointer; read-only */
108	int nonblock;			/**< non-block mode; read-only */
109
110	snd_pcm_access_t access;	/**< access type; filled after hw_params is called */
111	snd_pcm_format_t format;	/**< PCM format; filled after hw_params is called */
112	unsigned int channels;		/**< number of channels; filled after hw_params is called */
113	unsigned int rate;		/**< rate; filled after hw_params is called */
114	snd_pcm_uframes_t period_size;	/**< period size; filled after hw_params is called */
115	snd_pcm_uframes_t buffer_size;	/**< buffer size; filled after hw_params is called */
116};
117
118/** Callback table of ioplug */
119struct snd_pcm_ioplug_callback {
120	/**
121	 * start the PCM; required
122	 */
123	int (*start)(snd_pcm_ioplug_t *io);
124	/**
125	 * stop the PCM; required
126	 */
127	int (*stop)(snd_pcm_ioplug_t *io);
128	/**
129	 * get the current DMA position; required
130	 */
131	snd_pcm_sframes_t (*pointer)(snd_pcm_ioplug_t *io);
132	/**
133	 * transfer the data; optional
134	 */
135	snd_pcm_sframes_t (*transfer)(snd_pcm_ioplug_t *io,
136				      const snd_pcm_channel_area_t *areas,
137				      snd_pcm_uframes_t offset,
138				      snd_pcm_uframes_t size);
139	/**
140	 * close the PCM; optional
141	 */
142	int (*close)(snd_pcm_ioplug_t *io);
143	/**
144	 * hw_params; optional
145	 */
146	int (*hw_params)(snd_pcm_ioplug_t *io, snd_pcm_hw_params_t *params);
147	/**
148	 * hw_free; optional
149	 */
150	int (*hw_free)(snd_pcm_ioplug_t *io);
151	/**
152	 * sw_params; optional
153	 */
154	int (*sw_params)(snd_pcm_ioplug_t *io, snd_pcm_sw_params_t *params);
155	/**
156	 * prepare; optional
157	 */
158	int (*prepare)(snd_pcm_ioplug_t *io);
159	/**
160	 * drain; optional
161	 */
162	int (*drain)(snd_pcm_ioplug_t *io);
163	/**
164	 * toggle pause; optional
165	 */
166	int (*pause)(snd_pcm_ioplug_t *io, int enable);
167	/**
168	 * resume; optional
169	 */
170	int (*resume)(snd_pcm_ioplug_t *io);
171	/**
172	 * poll descriptors count; optional
173	 */
174	int (*poll_descriptors_count)(snd_pcm_ioplug_t *io);
175	/**
176	 * poll descriptors; optional
177	 */
178	int (*poll_descriptors)(snd_pcm_ioplug_t *io, struct pollfd *pfd, unsigned int space);
179	/**
180	 * mangle poll events; optional
181	 */
182	int (*poll_revents)(snd_pcm_ioplug_t *io, struct pollfd *pfd, unsigned int nfds, unsigned short *revents);
183	/**
184	 * dump; optional
185	 */
186	void (*dump)(snd_pcm_ioplug_t *io, snd_output_t *out);
187	/**
188	 * get the delay for the running PCM; optional
189	 */
190	int (*delay)(snd_pcm_ioplug_t *io, snd_pcm_sframes_t *delayp);
191};
192
193
194int snd_pcm_ioplug_create(snd_pcm_ioplug_t *io, const char *name,
195			  snd_pcm_stream_t stream, int mode);
196int snd_pcm_ioplug_delete(snd_pcm_ioplug_t *io);
197
198/* update poll_fd and mmap_rw */
199int snd_pcm_ioplug_reinit_status(snd_pcm_ioplug_t *ioplug);
200
201/* get a mmap area (for mmap_rw only) */
202const snd_pcm_channel_area_t *snd_pcm_ioplug_mmap_areas(snd_pcm_ioplug_t *ioplug);
203
204/* clear hw_parameter setting */
205void snd_pcm_ioplug_params_reset(snd_pcm_ioplug_t *io);
206
207/* hw_parameter setting */
208int snd_pcm_ioplug_set_param_minmax(snd_pcm_ioplug_t *io, int type, unsigned int min, unsigned int max);
209int snd_pcm_ioplug_set_param_list(snd_pcm_ioplug_t *io, int type, unsigned int num_list, const unsigned int *list);
210
211/** \} */
212
213#endif /* __ALSA_PCM_IOPLUG_H */
214