ALSA project - the C library reference
pcm_ioplug.h
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1 
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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
28  *
29  */
30 
31 #if !defined(__ALSA_PCM_EXTERNAL_H) && !defined(ALSA_LIBRARY_BUILD)
32 #warning "use #include <alsa/pcm_external.h>, <alsa/pcm_ioplug.h> should not be used directly"
33 #include <alsa/pcm_external.h>
34 #endif
35 
36 #ifndef __ALSA_PCM_IOPLUG_H
37 #define __ALSA_PCM_IOPLUG_H
38 
47 enum {
48  SND_PCM_IOPLUG_HW_ACCESS = 0,
49  SND_PCM_IOPLUG_HW_FORMAT,
50  SND_PCM_IOPLUG_HW_CHANNELS,
51  SND_PCM_IOPLUG_HW_RATE,
52  SND_PCM_IOPLUG_HW_PERIOD_BYTES,
53  SND_PCM_IOPLUG_HW_BUFFER_BYTES,
54  SND_PCM_IOPLUG_HW_PERIODS,
55  SND_PCM_IOPLUG_HW_PARAMS
56 };
57 
59 typedef struct snd_pcm_ioplug snd_pcm_ioplug_t;
61 typedef struct snd_pcm_ioplug_callback snd_pcm_ioplug_callback_t;
62 #ifdef DOC_HIDDEN
63 /* redefine typedefs for stupid doxygen */
64 typedef snd_pcm_ioplug snd_pcm_ioplug_t;
65 typedef snd_pcm_ioplug_callback snd_pcm_ioplug_callback_t;
66 #endif
67 
68 /*
69  * bit flags for additional conditions
70  */
71 #define SND_PCM_IOPLUG_FLAG_LISTED (1<<0)
72 #define SND_PCM_IOPLUG_FLAG_MONOTONIC (1<<1)
74 #define SND_PCM_IOPLUG_FLAG_BOUNDARY_WA (1<<2)
75 
76 /*
77  * Protocol version
78  */
79 #define SND_PCM_IOPLUG_VERSION_MAJOR 1
80 #define SND_PCM_IOPLUG_VERSION_MINOR 0
81 #define SND_PCM_IOPLUG_VERSION_TINY 2
85 #define SND_PCM_IOPLUG_VERSION ((SND_PCM_IOPLUG_VERSION_MAJOR<<16) |\
86  (SND_PCM_IOPLUG_VERSION_MINOR<<8) |\
87  (SND_PCM_IOPLUG_VERSION_TINY))
88 
90 struct snd_pcm_ioplug {
95  unsigned int version;
99  const char *name;
100  unsigned int flags;
101  int poll_fd;
102  unsigned int poll_events;
103  unsigned int mmap_rw;
107  const snd_pcm_ioplug_callback_t *callback;
111  void *private_data;
115  snd_pcm_t *pcm;
116 
117  snd_pcm_stream_t stream;
118  snd_pcm_state_t state;
119  volatile snd_pcm_uframes_t appl_ptr;
120  volatile snd_pcm_uframes_t hw_ptr;
121  int nonblock;
123  snd_pcm_access_t access;
125  unsigned int channels;
126  unsigned int rate;
127  snd_pcm_uframes_t period_size;
128  snd_pcm_uframes_t buffer_size;
129 };
130 
132 struct snd_pcm_ioplug_callback {
136  int (*start)(snd_pcm_ioplug_t *io);
140  int (*stop)(snd_pcm_ioplug_t *io);
147  snd_pcm_sframes_t (*pointer)(snd_pcm_ioplug_t *io);
151  snd_pcm_sframes_t (*transfer)(snd_pcm_ioplug_t *io,
152  const snd_pcm_channel_area_t *areas,
153  snd_pcm_uframes_t offset,
154  snd_pcm_uframes_t size);
158  int (*close)(snd_pcm_ioplug_t *io);
162  int (*hw_params)(snd_pcm_ioplug_t *io, snd_pcm_hw_params_t *params);
166  int (*hw_free)(snd_pcm_ioplug_t *io);
170  int (*sw_params)(snd_pcm_ioplug_t *io, snd_pcm_sw_params_t *params);
174  int (*prepare)(snd_pcm_ioplug_t *io);
178  int (*drain)(snd_pcm_ioplug_t *io);
182  int (*pause)(snd_pcm_ioplug_t *io, int enable);
186  int (*resume)(snd_pcm_ioplug_t *io);
190  int (*poll_descriptors_count)(snd_pcm_ioplug_t *io);
194  int (*poll_descriptors)(snd_pcm_ioplug_t *io, struct pollfd *pfd, unsigned int space);
198  int (*poll_revents)(snd_pcm_ioplug_t *io, struct pollfd *pfd, unsigned int nfds, unsigned short *revents);
202  void (*dump)(snd_pcm_ioplug_t *io, snd_output_t *out);
206  int (*delay)(snd_pcm_ioplug_t *io, snd_pcm_sframes_t *delayp);
210  snd_pcm_chmap_query_t **(*query_chmaps)(snd_pcm_ioplug_t *io);
214  snd_pcm_chmap_t *(*get_chmap)(snd_pcm_ioplug_t *io);
218  int (*set_chmap)(snd_pcm_ioplug_t *io, const snd_pcm_chmap_t *map);
219 };
220 
221 
222 int snd_pcm_ioplug_create(snd_pcm_ioplug_t *io, const char *name,
223  snd_pcm_stream_t stream, int mode);
224 int snd_pcm_ioplug_delete(snd_pcm_ioplug_t *io);
225 
226 /* update poll_fd and mmap_rw */
227 int snd_pcm_ioplug_reinit_status(snd_pcm_ioplug_t *ioplug);
228 
229 /* get a mmap area (for mmap_rw only) */
230 const snd_pcm_channel_area_t *snd_pcm_ioplug_mmap_areas(snd_pcm_ioplug_t *ioplug);
231 
232 /* clear hw_parameter setting */
233 void snd_pcm_ioplug_params_reset(snd_pcm_ioplug_t *io);
234 
235 /* hw_parameter setting */
236 int snd_pcm_ioplug_set_param_minmax(snd_pcm_ioplug_t *io, int type, unsigned int min, unsigned int max);
237 int snd_pcm_ioplug_set_param_list(snd_pcm_ioplug_t *io, int type, unsigned int num_list, const unsigned int *list);
238 
239 /* change PCM status */
240 int snd_pcm_ioplug_set_state(snd_pcm_ioplug_t *ioplug, snd_pcm_state_t state);
241 
242 /* calucalte the available frames */
243 snd_pcm_uframes_t snd_pcm_ioplug_avail(const snd_pcm_ioplug_t * const ioplug,
244  const snd_pcm_uframes_t hw_ptr,
245  const snd_pcm_uframes_t appl_ptr);
246 snd_pcm_uframes_t snd_pcm_ioplug_hw_avail(const snd_pcm_ioplug_t * const ioplug,
247  const snd_pcm_uframes_t hw_ptr,
248  const snd_pcm_uframes_t appl_ptr);
249 
252 #endif /* __ALSA_PCM_IOPLUG_H */
struct _snd_pcm_sw_params snd_pcm_sw_params_t
Definition: pcm.h:71
snd_pcm_uframes_t snd_pcm_ioplug_hw_avail(const snd_pcm_ioplug_t *const ioplug, const snd_pcm_uframes_t hw_ptr, const snd_pcm_uframes_t appl_ptr)
Get the available frames. This function can be used to calculate the the available frames before call...
Definition: pcm_ioplug.c:1270
int snd_pcm_ioplug_reinit_status(snd_pcm_ioplug_t *ioplug)
Reinitialize the poll and mmap status.
Definition: pcm_ioplug.c:1204
Definition: pcm.h:652
snd_pcm_state_t
Definition: pcm.h:303
uint8_t type
Definition: ump_msg.h:183
Definition: pcm.h:496
struct _snd_pcm_hw_params snd_pcm_hw_params_t
Definition: pcm.h:68
Definition: pcm.h:646
int snd_pcm_ioplug_set_param_minmax(snd_pcm_ioplug_t *ioplug, int type, unsigned int min, unsigned int max)
Set parameter as the min/max values.
Definition: pcm_ioplug.c:1179
const snd_pcm_channel_area_t * snd_pcm_ioplug_mmap_areas(snd_pcm_ioplug_t *ioplug)
Get mmap area of ioplug.
Definition: pcm_ioplug.c:1224
void snd_pcm_ioplug_params_reset(snd_pcm_ioplug_t *ioplug)
Reset ioplug parameters.
Definition: pcm_ioplug.c:1138
snd_pcm_format_t
Definition: pcm.h:129
long snd_pcm_sframes_t
Definition: pcm.h:402
int snd_pcm_ioplug_create(snd_pcm_ioplug_t *ioplug, const char *name, snd_pcm_stream_t stream, int mode)
Create an ioplug instance.
Definition: pcm_ioplug.c:1074
struct _snd_output snd_output_t
Internal structure for an output object.
Definition: output.h:60
int snd_pcm_ioplug_set_param_list(snd_pcm_ioplug_t *ioplug, int type, unsigned int num_list, const unsigned int *list)
Set parameter as the list.
Definition: pcm_ioplug.c:1155
uint16_t format
Definition: ump_msg.h:184
snd_pcm_uframes_t snd_pcm_ioplug_avail(const snd_pcm_ioplug_t *const ioplug, const snd_pcm_uframes_t hw_ptr, const snd_pcm_uframes_t appl_ptr)
Get the available frames. This function can be used to calculate the the available frames before call...
Definition: pcm_ioplug.c:1255
uint8_t flags
Definition: ump_msg.h:188
unsigned long snd_pcm_uframes_t
Definition: pcm.h:400
snd_pcm_stream_t
Definition: pcm.h:105
int snd_pcm_ioplug_delete(snd_pcm_ioplug_t *ioplug)
Delete the ioplug instance.
Definition: pcm_ioplug.c:1126
int snd_pcm_ioplug_set_state(snd_pcm_ioplug_t *ioplug, snd_pcm_state_t state)
Change the ioplug PCM status.
Definition: pcm_ioplug.c:1241
struct _snd_pcm snd_pcm_t
Definition: pcm.h:422
snd_pcm_access_t
Definition: pcm.h:114