pcm_ioplug.h

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/*
 * ALSA external PCM plugin SDK
 *
 * Copyright (c) 2005 Takashi Iwai <tiwai@suse.de>
 *
 *   This library is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as
 *   published by the Free Software Foundation; either version 2.1 of
 *   the License, or (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public
 *   License along with this library; if not, write to the Free Software
 *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */
 
#ifndef __ALSA_PCM_IOPLUG_H
#define __ALSA_PCM_IOPLUG_H
 
enum {
    SND_PCM_IOPLUG_HW_ACCESS = 0,   
    SND_PCM_IOPLUG_HW_FORMAT,   
    SND_PCM_IOPLUG_HW_CHANNELS, 
    SND_PCM_IOPLUG_HW_RATE,     
    SND_PCM_IOPLUG_HW_PERIOD_BYTES, 
    SND_PCM_IOPLUG_HW_BUFFER_BYTES, 
    SND_PCM_IOPLUG_HW_PERIODS,  
    SND_PCM_IOPLUG_HW_PARAMS    
};
    
typedef struct snd_pcm_ioplug snd_pcm_ioplug_t;
typedef struct snd_pcm_ioplug_callback snd_pcm_ioplug_callback_t;
#ifdef DOC_HIDDEN
/* redefine typedefs for stupid doxygen */
typedef snd_pcm_ioplug snd_pcm_ioplug_t;
typedef snd_pcm_ioplug_callback snd_pcm_ioplug_callback_t;
#endif
 
/*
 * bit flags for additional conditions
 */
#define SND_PCM_IOPLUG_FLAG_LISTED  (1<<0)      
#define SND_PCM_IOPLUG_FLAG_MONOTONIC   (1<<1)      
#define SND_PCM_IOPLUG_FLAG_BOUNDARY_WA (1<<2)
 
/*
 * Protocol version
 */
#define SND_PCM_IOPLUG_VERSION_MAJOR    1   
#define SND_PCM_IOPLUG_VERSION_MINOR    0   
#define SND_PCM_IOPLUG_VERSION_TINY 2   
#define SND_PCM_IOPLUG_VERSION      ((SND_PCM_IOPLUG_VERSION_MAJOR<<16) |\
                     (SND_PCM_IOPLUG_VERSION_MINOR<<8) |\
                     (SND_PCM_IOPLUG_VERSION_TINY))
 
struct snd_pcm_ioplug {
    unsigned int version;
    const char *name;
    unsigned int flags; 
    int poll_fd;        
    unsigned int poll_events;   
    unsigned int mmap_rw;       
    const snd_pcm_ioplug_callback_t *callback;
    void *private_data;
    snd_pcm_t *pcm;
 
    snd_pcm_stream_t stream;    
    snd_pcm_state_t state;      
    volatile snd_pcm_uframes_t appl_ptr;    
    volatile snd_pcm_uframes_t hw_ptr;  
    int nonblock;           
    snd_pcm_access_t access;    
    snd_pcm_format_t format;    
    unsigned int channels;      
    unsigned int rate;      
    snd_pcm_uframes_t period_size;  
    snd_pcm_uframes_t buffer_size;  
};
 
struct snd_pcm_ioplug_callback {
    int (*start)(snd_pcm_ioplug_t *io);
    int (*stop)(snd_pcm_ioplug_t *io);
    snd_pcm_sframes_t (*pointer)(snd_pcm_ioplug_t *io);
    snd_pcm_sframes_t (*transfer)(snd_pcm_ioplug_t *io,
                      const snd_pcm_channel_area_t *areas,
                      snd_pcm_uframes_t offset,
                      snd_pcm_uframes_t size);
    int (*close)(snd_pcm_ioplug_t *io);
    int (*hw_params)(snd_pcm_ioplug_t *io, snd_pcm_hw_params_t *params);
    int (*hw_free)(snd_pcm_ioplug_t *io);
    int (*sw_params)(snd_pcm_ioplug_t *io, snd_pcm_sw_params_t *params);
    int (*prepare)(snd_pcm_ioplug_t *io);
    int (*drain)(snd_pcm_ioplug_t *io);
    int (*pause)(snd_pcm_ioplug_t *io, int enable);
    int (*resume)(snd_pcm_ioplug_t *io);
    int (*poll_descriptors_count)(snd_pcm_ioplug_t *io);
    int (*poll_descriptors)(snd_pcm_ioplug_t *io, struct pollfd *pfd, unsigned int space);
    int (*poll_revents)(snd_pcm_ioplug_t *io, struct pollfd *pfd, unsigned int nfds, unsigned short *revents);
    void (*dump)(snd_pcm_ioplug_t *io, snd_output_t *out);
    int (*delay)(snd_pcm_ioplug_t *io, snd_pcm_sframes_t *delayp);
    snd_pcm_chmap_query_t **(*query_chmaps)(snd_pcm_ioplug_t *io);
    snd_pcm_chmap_t *(*get_chmap)(snd_pcm_ioplug_t *io);
    int (*set_chmap)(snd_pcm_ioplug_t *io, const snd_pcm_chmap_t *map);
};
 
 
int snd_pcm_ioplug_create(snd_pcm_ioplug_t *io, const char *name,
              snd_pcm_stream_t stream, int mode);
int snd_pcm_ioplug_delete(snd_pcm_ioplug_t *io);
 
/* update poll_fd and mmap_rw */
int snd_pcm_ioplug_reinit_status(snd_pcm_ioplug_t *ioplug);
 
/* get a mmap area (for mmap_rw only) */
const snd_pcm_channel_area_t *snd_pcm_ioplug_mmap_areas(snd_pcm_ioplug_t *ioplug);
 
/* clear hw_parameter setting */
void snd_pcm_ioplug_params_reset(snd_pcm_ioplug_t *io);
 
/* hw_parameter setting */
int snd_pcm_ioplug_set_param_minmax(snd_pcm_ioplug_t *io, int type, unsigned int min, unsigned int max);
int snd_pcm_ioplug_set_param_list(snd_pcm_ioplug_t *io, int type, unsigned int num_list, const unsigned int *list);
 
/* change PCM status */
int snd_pcm_ioplug_set_state(snd_pcm_ioplug_t *ioplug, snd_pcm_state_t state);
 
/* calucalte the available frames */
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);
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);
 
#endif /* __ALSA_PCM_IOPLUG_H */