#ifndef __SOUND_PCM_H #define __SOUND_PCM_H /* * Digital Audio (PCM) abstract layer * Copyright (c) by Jaroslav Kysela * Abramo Bagnara * * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * */ #include #include #include #include #include #include #include #define snd_pcm_substream_chip(substream) ((substream)->private_data) #define snd_pcm_chip(pcm) ((pcm)->private_data) #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE) #include "pcm_oss.h" #endif /* * Hardware (lowlevel) section */ struct snd_pcm_hardware { unsigned int info; /* SNDRV_PCM_INFO_* */ u64 formats; /* SNDRV_PCM_FMTBIT_* */ unsigned int rates; /* SNDRV_PCM_RATE_* */ unsigned int rate_min; /* min rate */ unsigned int rate_max; /* max rate */ unsigned int channels_min; /* min channels */ unsigned int channels_max; /* max channels */ size_t buffer_bytes_max; /* max buffer size */ size_t period_bytes_min; /* min period size */ size_t period_bytes_max; /* max period size */ unsigned int periods_min; /* min # of periods */ unsigned int periods_max; /* max # of periods */ size_t fifo_size; /* fifo size in bytes */ }; struct snd_pcm_substream; struct snd_pcm_ops { int (*open)(struct snd_pcm_substream *substream); int (*close)(struct snd_pcm_substream *substream); int (*ioctl)(struct snd_pcm_substream * substream, unsigned int cmd, void *arg); int (*hw_params)(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params); int (*hw_free)(struct snd_pcm_substream *substream); int (*prepare)(struct snd_pcm_substream *substream); int (*trigger)(struct snd_pcm_substream *substream, int cmd); snd_pcm_uframes_t (*pointer)(struct snd_pcm_substream *substream); int (*copy)(struct snd_pcm_substream *substream, int channel, snd_pcm_uframes_t pos, void __user *buf, snd_pcm_uframes_t count); int (*silence)(struct snd_pcm_substream *substream, int channel, snd_pcm_uframes_t pos, snd_pcm_uframes_t count); struct page *(*page)(struct snd_pcm_substream *substream, unsigned long offset); int (*mmap)(struct snd_pcm_substream *substream, struct vm_area_struct *vma); int (*ack)(struct snd_pcm_substream *substream); int (*restart)(struct snd_pcm_substream *substream); }; /* * */ #if defined(CONFIG_SND_DYNAMIC_MINORS) #define SNDRV_PCM_DEVICES (SNDRV_OS_MINORS-2) #else #define SNDRV_PCM_DEVICES 8 #endif #define SNDRV_PCM_IOCTL1_FALSE ((void *)0) #define SNDRV_PCM_IOCTL1_TRUE ((void *)1) #define SNDRV_PCM_IOCTL1_RESET 0 #define SNDRV_PCM_IOCTL1_INFO 1 #define SNDRV_PCM_IOCTL1_CHANNEL_INFO 2 #define SNDRV_PCM_IOCTL1_GSTATE 3 #define SNDRV_PCM_IOCTL1_FIFO_SIZE 4 #define SNDRV_PCM_TRIGGER_STOP 0 #define SNDRV_PCM_TRIGGER_START 1 #define SNDRV_PCM_TRIGGER_PAUSE_PUSH 3 #define SNDRV_PCM_TRIGGER_PAUSE_RELEASE 4 #define SNDRV_PCM_TRIGGER_SUSPEND 5 #define SNDRV_PCM_TRIGGER_RESUME 6 #define SNDRV_PCM_POS_XRUN ((snd_pcm_uframes_t)-1) #define SNDRV_DMA_MODE (0) #define SNDRV_NON_DMA_MODE (1 << 0) #define SNDRV_RENDER_STOPPED (1 << 1) #define SNDRV_RENDER_RUNNING (1 << 2) /* If you change this don't forget to change rates[] table in pcm_native.c */ #define SNDRV_PCM_RATE_5512 (1<<0) /* 5512Hz */ #define SNDRV_PCM_RATE_8000 (1<<1) /* 8000Hz */ #define SNDRV_PCM_RATE_11025 (1<<2) /* 11025Hz */ #define SNDRV_PCM_RATE_16000 (1<<3) /* 16000Hz */ #define SNDRV_PCM_RATE_22050 (1<<4) /* 22050Hz */ #define SNDRV_PCM_RATE_32000 (1<<5) /* 32000Hz */ #define SNDRV_PCM_RATE_44100 (1<<6) /* 44100Hz */ #define SNDRV_PCM_RATE_48000 (1<<7) /* 48000Hz */ #define SNDRV_PCM_RATE_64000 (1<<8) /* 64000Hz */ #define SNDRV_PCM_RATE_88200 (1<<9) /* 88200Hz */ #define SNDRV_PCM_RATE_96000 (1<<10) /* 96000Hz */ #define SNDRV_PCM_RATE_176400 (1<<11) /* 176400Hz */ #define SNDRV_PCM_RATE_192000 (1<<12) /* 192000Hz */ #define SNDRV_PCM_RATE_CONTINUOUS (1<<30) /* continuous range */ #define SNDRV_PCM_RATE_KNOT (1<<31) /* supports more non-continuos rates */ #define SNDRV_PCM_RATE_8000_44100 (SNDRV_PCM_RATE_8000|SNDRV_PCM_RATE_11025|\ SNDRV_PCM_RATE_16000|SNDRV_PCM_RATE_22050|\ SNDRV_PCM_RATE_32000|SNDRV_PCM_RATE_44100) #define SNDRV_PCM_RATE_8000_48000 (SNDRV_PCM_RATE_8000_44100|SNDRV_PCM_RATE_48000) #define SNDRV_PCM_RATE_8000_96000 (SNDRV_PCM_RATE_8000_48000|SNDRV_PCM_RATE_64000|\ SNDRV_PCM_RATE_88200|SNDRV_PCM_RATE_96000) #define SNDRV_PCM_RATE_8000_192000 (SNDRV_PCM_RATE_8000_96000|SNDRV_PCM_RATE_176400|\ SNDRV_PCM_RATE_192000) #define _SNDRV_PCM_FMTBIT(fmt) (1ULL << (__force int)SNDRV_PCM_FORMAT_##fmt) #define SNDRV_PCM_FMTBIT_S8 _SNDRV_PCM_FMTBIT(S8) #define SNDRV_PCM_FMTBIT_U8 _SNDRV_PCM_FMTBIT(U8) #define SNDRV_PCM_FMTBIT_S16_LE _SNDRV_PCM_FMTBIT(S16_LE) #define SNDRV_PCM_FMTBIT_S16_BE _SNDRV_PCM_FMTBIT(S16_BE) #define SNDRV_PCM_FMTBIT_U16_LE _SNDRV_PCM_FMTBIT(U16_LE) #define SNDRV_PCM_FMTBIT_U16_BE _SNDRV_PCM_FMTBIT(U16_BE) #define SNDRV_PCM_FMTBIT_S24_LE _SNDRV_PCM_FMTBIT(S24_LE) #define SNDRV_PCM_FMTBIT_S24_BE _SNDRV_PCM_FMTBIT(S24_BE) #define SNDRV_PCM_FMTBIT_U24_LE _SNDRV_PCM_FMTBIT(U24_LE) #define SNDRV_PCM_FMTBIT_U24_BE _SNDRV_PCM_FMTBIT(U24_BE) #define SNDRV_PCM_FMTBIT_S32_LE _SNDRV_PCM_FMTBIT(S32_LE) #define SNDRV_PCM_FMTBIT_S32_BE _SNDRV_PCM_FMTBIT(S32_BE) #define SNDRV_PCM_FMTBIT_U32_LE _SNDRV_PCM_FMTBIT(U32_LE) #define SNDRV_PCM_FMTBIT_U32_BE _SNDRV_PCM_FMTBIT(U32_BE) #define SNDRV_PCM_FMTBIT_FLOAT_LE _SNDRV_PCM_FMTBIT(FLOAT_LE) #define SNDRV_PCM_FMTBIT_FLOAT_BE _SNDRV_PCM_FMTBIT(FLOAT_BE) #define SNDRV_PCM_FMTBIT_FLOAT64_LE _SNDRV_PCM_FMTBIT(FLOAT64_LE) #define SNDRV_PCM_FMTBIT_FLOAT64_BE _SNDRV_PCM_FMTBIT(FLOAT64_BE) #define SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE _SNDRV_PCM_FMTBIT(IEC958_SUBFRAME_LE) #define SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_BE _SNDRV_PCM_FMTBIT(IEC958_SUBFRAME_BE) #define SNDRV_PCM_FMTBIT_MU_LAW _SNDRV_PCM_FMTBIT(MU_LAW) #define SNDRV_PCM_FMTBIT_A_LAW _SNDRV_PCM_FMTBIT(A_LAW) #define SNDRV_PCM_FMTBIT_IMA_ADPCM _SNDRV_PCM_FMTBIT(IMA_ADPCM) #define SNDRV_PCM_FMTBIT_MPEG _SNDRV_PCM_FMTBIT(MPEG) #define SNDRV_PCM_FMTBIT_GSM _SNDRV_PCM_FMTBIT(GSM) #define SNDRV_PCM_FMTBIT_SPECIAL _SNDRV_PCM_FMTBIT(SPECIAL) #define SNDRV_PCM_FMTBIT_S24_3LE _SNDRV_PCM_FMTBIT(S24_3LE) #define SNDRV_PCM_FMTBIT_U24_3LE _SNDRV_PCM_FMTBIT(U24_3LE) #define SNDRV_PCM_FMTBIT_S24_3BE _SNDRV_PCM_FMTBIT(S24_3BE) #define SNDRV_PCM_FMTBIT_U24_3BE _SNDRV_PCM_FMTBIT(U24_3BE) #define SNDRV_PCM_FMTBIT_S20_3LE _SNDRV_PCM_FMTBIT(S20_3LE) #define SNDRV_PCM_FMTBIT_U20_3LE _SNDRV_PCM_FMTBIT(U20_3LE) #define SNDRV_PCM_FMTBIT_S20_3BE _SNDRV_PCM_FMTBIT(S20_3BE) #define SNDRV_PCM_FMTBIT_U20_3BE _SNDRV_PCM_FMTBIT(U20_3BE) #define SNDRV_PCM_FMTBIT_S18_3LE _SNDRV_PCM_FMTBIT(S18_3LE) #define SNDRV_PCM_FMTBIT_U18_3LE _SNDRV_PCM_FMTBIT(U18_3LE) #define SNDRV_PCM_FMTBIT_S18_3BE _SNDRV_PCM_FMTBIT(S18_3BE) #define SNDRV_PCM_FMTBIT_U18_3BE _SNDRV_PCM_FMTBIT(U18_3BE) #define SNDRV_PCM_FMTBIT_G723_24 _SNDRV_PCM_FMTBIT(G723_24) #define SNDRV_PCM_FMTBIT_G723_24_1B _SNDRV_PCM_FMTBIT(G723_24_1B) #define SNDRV_PCM_FMTBIT_G723_40 _SNDRV_PCM_FMTBIT(G723_40) #define SNDRV_PCM_FMTBIT_G723_40_1B _SNDRV_PCM_FMTBIT(G723_40_1B) #ifdef SNDRV_LITTLE_ENDIAN #define SNDRV_PCM_FMTBIT_S16 SNDRV_PCM_FMTBIT_S16_LE #define SNDRV_PCM_FMTBIT_U16 SNDRV_PCM_FMTBIT_U16_LE #define SNDRV_PCM_FMTBIT_S24 SNDRV_PCM_FMTBIT_S24_LE #define SNDRV_PCM_FMTBIT_U24 SNDRV_PCM_FMTBIT_U24_LE #define SNDRV_PCM_FMTBIT_S32 SNDRV_PCM_FMTBIT_S32_LE #define SNDRV_PCM_FMTBIT_U32 SNDRV_PCM_FMTBIT_U32_LE #define SNDRV_PCM_FMTBIT_FLOAT SNDRV_PCM_FMTBIT_FLOAT_LE #define SNDRV_PCM_FMTBIT_FLOAT64 SNDRV_PCM_FMTBIT_FLOAT64_LE #define SNDRV_PCM_FMTBIT_IEC958_SUBFRAME SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE #endif #ifdef SNDRV_BIG_ENDIAN #define SNDRV_PCM_FMTBIT_S16 SNDRV_PCM_FMTBIT_S16_BE #define SNDRV_PCM_FMTBIT_U16 SNDRV_PCM_FMTBIT_U16_BE #define SNDRV_PCM_FMTBIT_S24 SNDRV_PCM_FMTBIT_S24_BE #define SNDRV_PCM_FMTBIT_U24 SNDRV_PCM_FMTBIT_U24_BE #define SNDRV_PCM_FMTBIT_S32 SNDRV_PCM_FMTBIT_S32_BE #define SNDRV_PCM_FMTBIT_U32 SNDRV_PCM_FMTBIT_U32_BE #define SNDRV_PCM_FMTBIT_FLOAT SNDRV_PCM_FMTBIT_FLOAT_BE #define SNDRV_PCM_FMTBIT_FLOAT64 SNDRV_PCM_FMTBIT_FLOAT64_BE #define SNDRV_PCM_FMTBIT_IEC958_SUBFRAME SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_BE #endif struct snd_pcm_file { struct snd_pcm_substream *substream; int no_compat_mmap; }; struct snd_pcm_hw_rule; typedef int (*snd_pcm_hw_rule_func_t)(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule); struct snd_pcm_hw_rule { unsigned int cond; snd_pcm_hw_rule_func_t func; int var; int deps[4]; void *private; }; struct snd_pcm_hw_constraints { struct snd_mask masks[SNDRV_PCM_HW_PARAM_LAST_MASK - SNDRV_PCM_HW_PARAM_FIRST_MASK + 1]; struct snd_interval intervals[SNDRV_PCM_HW_PARAM_LAST_INTERVAL - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL + 1]; unsigned int rules_num; unsigned int rules_all; struct snd_pcm_hw_rule *rules; }; static inline struct snd_mask *constrs_mask(struct snd_pcm_hw_constraints *constrs, snd_pcm_hw_param_t var) { return &constrs->masks[var - SNDRV_PCM_HW_PARAM_FIRST_MASK]; } static inline struct snd_interval *constrs_interval(struct snd_pcm_hw_constraints *constrs, snd_pcm_hw_param_t var) { return &constrs->intervals[var - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL]; } struct snd_ratnum { unsigned int num; unsigned int den_min, den_max, den_step; }; struct snd_ratden { unsigned int num_min, num_max, num_step; unsigned int den; }; struct snd_pcm_hw_constraint_ratnums { int nrats; struct snd_ratnum *rats; }; struct snd_pcm_hw_constraint_ratdens { int nrats; struct snd_ratden *rats; }; struct snd_pcm_hw_constraint_list { unsigned int count; unsigned int *list; unsigned int mask; }; struct snd_pcm_hwptr_log; struct snd_pcm_runtime { /* -- Status -- */ struct snd_pcm_substream *trigger_master; struct timespec trigger_tstamp; /* trigger timestamp */ int overrange; snd_pcm_uframes_t avail_max; snd_pcm_uframes_t hw_ptr_base; /* Position at buffer restart */ snd_pcm_uframes_t hw_ptr_interrupt; /* Position at interrupt time */ unsigned long hw_ptr_jiffies; /* Time when hw_ptr is updated */ unsigned long hw_ptr_buffer_jiffies; /* buffer time in jiffies */ snd_pcm_sframes_t delay; /* extra delay; typically FIFO size */ /* -- HW params -- */ snd_pcm_access_t access; /* access mode */ snd_pcm_format_t format; /* SNDRV_PCM_FORMAT_* */ snd_pcm_subformat_t subformat; /* subformat */ unsigned int rate; /* rate in Hz */ unsigned int channels; /* channels */ snd_pcm_uframes_t period_size; /* period size */ unsigned int periods; /* periods */ snd_pcm_uframes_t buffer_size; /* buffer size */ snd_pcm_uframes_t min_align; /* Min alignment for the format */ size_t byte_align; unsigned int frame_bits; unsigned int sample_bits; unsigned int info; unsigned int rate_num; unsigned int rate_den; unsigned int no_period_wakeup: 1; unsigned int render_flag; /* -- SW params -- */ int tstamp_mode; /* mmap timestamp is updated */ unsigned int period_step; snd_pcm_uframes_t start_threshold; snd_pcm_uframes_t stop_threshold; snd_pcm_uframes_t silence_threshold; /* Silence filling happens when noise is nearest than this */ snd_pcm_uframes_t silence_size; /* Silence filling size */ snd_pcm_uframes_t boundary; /* pointers wrap point */ snd_pcm_uframes_t silence_start; /* starting pointer to silence area */ snd_pcm_uframes_t silence_filled; /* size filled with silence */ union snd_pcm_sync_id sync; /* hardware synchronization ID */ /* -- mmap -- */ struct snd_pcm_mmap_status *status; struct snd_pcm_mmap_control *control; /* -- locking / scheduling -- */ snd_pcm_uframes_t twake; /* do transfer (!poll) wakeup if non-zero */ wait_queue_head_t sleep; /* poll sleep */ wait_queue_head_t tsleep; /* transfer sleep */ struct fasync_struct *fasync; /* -- private section -- */ void *private_data; void (*private_free)(struct snd_pcm_runtime *runtime); /* -- hardware description -- */ struct snd_pcm_hardware hw; struct snd_pcm_hw_constraints hw_constraints; /* -- interrupt callbacks -- */ void (*transfer_ack_begin)(struct snd_pcm_substream *substream); void (*transfer_ack_end)(struct snd_pcm_substream *substream); /* -- timer -- */ unsigned int timer_resolution; /* timer resolution */ int tstamp_type; /* timestamp type */ /* -- DMA -- */ unsigned char *dma_area; /* DMA area */ dma_addr_t dma_addr; /* physical bus address (not accessible from main CPU) */ size_t dma_bytes; /* size of DMA area */ struct snd_dma_buffer *dma_buffer_p; /* allocated buffer */ #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE) /* -- OSS things -- */ struct snd_pcm_oss_runtime oss; #endif #ifdef CONFIG_SND_PCM_XRUN_DEBUG struct snd_pcm_hwptr_log *hwptr_log; #endif }; struct snd_pcm_group { /* keep linked substreams */ spinlock_t lock; struct list_head substreams; int count; }; struct pid; struct snd_pcm_substream { struct snd_pcm *pcm; struct snd_pcm_str *pstr; void *private_data; /* copied from pcm->private_data */ int number; char name[32]; /* substream name */ int stream; /* stream (direction) */ struct pm_qos_request latency_pm_qos_req; /* pm_qos request */ size_t buffer_bytes_max; /* limit ring buffer size */ struct snd_dma_buffer dma_buffer; unsigned int dma_buf_id; size_t dma_max; /* -- hardware operations -- */ struct snd_pcm_ops *ops; /* -- runtime information -- */ struct snd_pcm_runtime *runtime; /* -- timer section -- */ struct snd_timer *timer; /* timer */ unsigned timer_running: 1; /* time is running */ /* -- next substream -- */ struct snd_pcm_substream *next; /* -- linked substreams -- */ struct list_head link_list; /* linked list member */ struct snd_pcm_group self_group; /* fake group for non linked substream (with substream lock inside) */ struct snd_pcm_group *group; /* pointer to current group */ /* -- assigned files -- */ void *file; int ref_count; atomic_t mmap_count; unsigned int f_flags; void (*pcm_release)(struct snd_pcm_substream *); struct pid *pid; #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE) /* -- OSS things -- */ struct snd_pcm_oss_substream oss; #endif #ifdef CONFIG_SND_VERBOSE_PROCFS struct snd_info_entry *proc_root; struct snd_info_entry *proc_info_entry; struct snd_info_entry *proc_hw_params_entry; struct snd_info_entry *proc_sw_params_entry; struct snd_info_entry *proc_status_entry; struct snd_info_entry *proc_prealloc_entry; struct snd_info_entry *proc_prealloc_max_entry; #endif /* misc flags */ unsigned int hw_opened: 1; unsigned int hw_no_buffer: 1; /* substream may not have a buffer */ }; #define SUBSTREAM_BUSY(substream) ((substream)->ref_count > 0) struct snd_pcm_str { int stream; /* stream (direction) */ struct snd_pcm *pcm; /* -- substreams -- */ unsigned int substream_count; unsigned int substream_opened; struct snd_pcm_substream *substream; #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE) /* -- OSS things -- */ struct snd_pcm_oss_stream oss; #endif #ifdef CONFIG_SND_VERBOSE_PROCFS struct snd_info_entry *proc_root; struct snd_info_entry *proc_info_entry; #ifdef CONFIG_SND_PCM_XRUN_DEBUG unsigned int xrun_debug; /* 0 = disabled, 1 = verbose, 2 = stacktrace */ struct snd_info_entry *proc_xrun_debug_entry; #endif #endif struct snd_kcontrol *chmap_kctl; /* channel-mapping controls */ struct snd_kcontrol *vol_kctl; /* volume controls */ }; struct snd_pcm { struct snd_card *card; struct list_head list; int device; /* device number */ unsigned int info_flags; unsigned short dev_class; unsigned short dev_subclass; char id[64]; char name[80]; struct snd_pcm_str streams[2]; struct mutex open_mutex; wait_queue_head_t open_wait; void *private_data; void (*private_free) (struct snd_pcm *pcm); struct device *dev; /* actual hw device this belongs to */ #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE) struct snd_pcm_oss oss; #endif }; struct snd_pcm_notify { int (*n_register) (struct snd_pcm * pcm); int (*n_disconnect) (struct snd_pcm * pcm); int (*n_unregister) (struct snd_pcm * pcm); struct list_head list; }; /* * Registering */ extern const struct file_operations snd_pcm_f_ops[2]; int snd_pcm_new(struct snd_card *card, const char *id, int device, int playback_count, int capture_count, struct snd_pcm **rpcm); int snd_pcm_new_soc_be(struct snd_card *card, const char *id, int device, int playback_count, int capture_count, struct snd_pcm ** rpcm); int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count); int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree); /* * Native I/O */ extern rwlock_t snd_pcm_link_rwlock; int snd_pcm_info(struct snd_pcm_substream *substream, struct snd_pcm_info *info); int snd_pcm_info_user(struct snd_pcm_substream *substream, struct snd_pcm_info __user *info); int snd_pcm_status(struct snd_pcm_substream *substream, struct snd_pcm_status *status); int snd_pcm_start(struct snd_pcm_substream *substream); int snd_pcm_stop(struct snd_pcm_substream *substream, snd_pcm_state_t status); int snd_pcm_drain_done(struct snd_pcm_substream *substream); #ifdef CONFIG_PM int snd_pcm_suspend(struct snd_pcm_substream *substream); int snd_pcm_suspend_all(struct snd_pcm *pcm); #endif int snd_pcm_kernel_ioctl(struct snd_pcm_substream *substream, unsigned int cmd, void *arg); int snd_pcm_open_substream(struct snd_pcm *pcm, int stream, struct file *file, struct snd_pcm_substream **rsubstream); void snd_pcm_release_substream(struct snd_pcm_substream *substream); int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream, struct file *file, struct snd_pcm_substream **rsubstream); void snd_pcm_detach_substream(struct snd_pcm_substream *substream); void snd_pcm_vma_notify_data(void *client, void *data); int snd_pcm_mmap_data(struct snd_pcm_substream *substream, struct file *file, struct vm_area_struct *area); #ifdef CONFIG_SND_DEBUG void snd_pcm_debug_name(struct snd_pcm_substream *substream, char *name, size_t len); #else static inline void snd_pcm_debug_name(struct snd_pcm_substream *substream, char *buf, size_t size) { *buf = 0; } #endif /* * PCM library */ static inline int snd_pcm_stream_linked(struct snd_pcm_substream *substream) { return substream->group != &substream->self_group; } static inline void snd_pcm_stream_lock(struct snd_pcm_substream *substream) { read_lock(&snd_pcm_link_rwlock); spin_lock(&substream->self_group.lock); } static inline void snd_pcm_stream_unlock(struct snd_pcm_substream *substream) { spin_unlock(&substream->self_group.lock); read_unlock(&snd_pcm_link_rwlock); } static inline void snd_pcm_stream_lock_irq(struct snd_pcm_substream *substream) { read_lock_irq(&snd_pcm_link_rwlock); spin_lock(&substream->self_group.lock); } static inline void snd_pcm_stream_unlock_irq(struct snd_pcm_substream *substream) { spin_unlock(&substream->self_group.lock); read_unlock_irq(&snd_pcm_link_rwlock); } #define snd_pcm_stream_lock_irqsave(substream, flags) \ do { \ read_lock_irqsave(&snd_pcm_link_rwlock, (flags)); \ spin_lock(&substream->self_group.lock); \ } while (0) #define snd_pcm_stream_unlock_irqrestore(substream, flags) \ do { \ spin_unlock(&substream->self_group.lock); \ read_unlock_irqrestore(&snd_pcm_link_rwlock, (flags)); \ } while (0) #define snd_pcm_group_for_each_entry(s, substream) \ list_for_each_entry(s, &substream->group->substreams, link_list) static inline int snd_pcm_running(struct snd_pcm_substream *substream) { return (substream->runtime->status->state == SNDRV_PCM_STATE_RUNNING || (substream->runtime->status->state == SNDRV_PCM_STATE_DRAINING && substream->stream == SNDRV_PCM_STREAM_PLAYBACK)); } static inline ssize_t bytes_to_samples(struct snd_pcm_runtime *runtime, ssize_t size) { return size * 8 / runtime->sample_bits; } static inline snd_pcm_sframes_t bytes_to_frames(struct snd_pcm_runtime *runtime, ssize_t size) { return size * 8 / runtime->frame_bits; } static inline ssize_t samples_to_bytes(struct snd_pcm_runtime *runtime, ssize_t size) { return size * runtime->sample_bits / 8; } static inline ssize_t frames_to_bytes(struct snd_pcm_runtime *runtime, snd_pcm_sframes_t size) { return size * runtime->frame_bits / 8; } static inline int frame_aligned(struct snd_pcm_runtime *runtime, ssize_t bytes) { return bytes % runtime->byte_align == 0; } static inline size_t snd_pcm_lib_buffer_bytes(struct snd_pcm_substream *substream) { struct snd_pcm_runtime *runtime = substream->runtime; return frames_to_bytes(runtime, runtime->buffer_size); } static inline size_t snd_pcm_lib_period_bytes(struct snd_pcm_substream *substream) { struct snd_pcm_runtime *runtime = substream->runtime; return frames_to_bytes(runtime, runtime->period_size); } /* * result is: 0 ... (boundary - 1) */ static inline snd_pcm_uframes_t snd_pcm_playback_avail(struct snd_pcm_runtime *runtime) { snd_pcm_sframes_t avail = runtime->status->hw_ptr + runtime->buffer_size - runtime->control->appl_ptr; if (avail < 0) avail += runtime->boundary; else if ((snd_pcm_uframes_t) avail >= runtime->boundary) avail -= runtime->boundary; return avail; } /* * result is: 0 ... (boundary - 1) */ static inline snd_pcm_uframes_t snd_pcm_capture_avail(struct snd_pcm_runtime *runtime) { snd_pcm_sframes_t avail = runtime->status->hw_ptr - runtime->control->appl_ptr; if (avail < 0) avail += runtime->boundary; return avail; } static inline snd_pcm_sframes_t snd_pcm_playback_hw_avail(struct snd_pcm_runtime *runtime) { return runtime->buffer_size - snd_pcm_playback_avail(runtime); } static inline snd_pcm_sframes_t snd_pcm_capture_hw_avail(struct snd_pcm_runtime *runtime) { return runtime->buffer_size - snd_pcm_capture_avail(runtime); } /** * snd_pcm_playback_ready - check whether the playback buffer is available * @substream: the pcm substream instance * * Checks whether enough free space is available on the playback buffer. * * Returns non-zero if available, or zero if not. */ static inline int snd_pcm_playback_ready(struct snd_pcm_substream *substream) { struct snd_pcm_runtime *runtime = substream->runtime; return snd_pcm_playback_avail(runtime) >= runtime->control->avail_min; } /** * snd_pcm_capture_ready - check whether the capture buffer is available * @substream: the pcm substream instance * * Checks whether enough capture data is available on the capture buffer. * * Returns non-zero if available, or zero if not. */ static inline int snd_pcm_capture_ready(struct snd_pcm_substream *substream) { struct snd_pcm_runtime *runtime = substream->runtime; return snd_pcm_capture_avail(runtime) >= runtime->control->avail_min; } /** * snd_pcm_playback_data - check whether any data exists on the playback buffer * @substream: the pcm substream instance * * Checks whether any data exists on the playback buffer. If stop_threshold * is bigger or equal to boundary, then this function returns always non-zero. * * Returns non-zero if exists, or zero if not. */ static inline int snd_pcm_playback_data(struct snd_pcm_substream *substream) { struct snd_pcm_runtime *runtime = substream->runtime; if (runtime->stop_threshold >= runtime->boundary) return 1; return snd_pcm_playback_avail(runtime) < runtime->buffer_size; } /** * snd_pcm_playback_empty - check whether the playback buffer is empty * @substream: the pcm substream instance * * Checks whether the playback buffer is empty. * * Returns non-zero if empty, or zero if not. */ static inline int snd_pcm_playback_empty(struct snd_pcm_substream *substream) { struct snd_pcm_runtime *runtime = substream->runtime; return snd_pcm_playback_avail(runtime) >= runtime->buffer_size; } /** * snd_pcm_capture_empty - check whether the capture buffer is empty * @substream: the pcm substream instance * * Checks whether the capture buffer is empty. * * Returns non-zero if empty, or zero if not. */ static inline int snd_pcm_capture_empty(struct snd_pcm_substream *substream) { struct snd_pcm_runtime *runtime = substream->runtime; return snd_pcm_capture_avail(runtime) == 0; } static inline void snd_pcm_trigger_done(struct snd_pcm_substream *substream, struct snd_pcm_substream *master) { substream->runtime->trigger_master = master; } static inline int hw_is_mask(int var) { return var >= SNDRV_PCM_HW_PARAM_FIRST_MASK && var <= SNDRV_PCM_HW_PARAM_LAST_MASK; } static inline int hw_is_interval(int var) { return var >= SNDRV_PCM_HW_PARAM_FIRST_INTERVAL && var <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; } static inline struct snd_mask *hw_param_mask(struct snd_pcm_hw_params *params, snd_pcm_hw_param_t var) { return ¶ms->masks[var - SNDRV_PCM_HW_PARAM_FIRST_MASK]; } static inline struct snd_interval *hw_param_interval(struct snd_pcm_hw_params *params, snd_pcm_hw_param_t var) { return ¶ms->intervals[var - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL]; } static inline const struct snd_mask *hw_param_mask_c(const struct snd_pcm_hw_params *params, snd_pcm_hw_param_t var) { return ¶ms->masks[var - SNDRV_PCM_HW_PARAM_FIRST_MASK]; } static inline const struct snd_interval *hw_param_interval_c(const struct snd_pcm_hw_params *params, snd_pcm_hw_param_t var) { return ¶ms->intervals[var - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL]; } #define params_channels(p) \ (hw_param_interval_c((p), SNDRV_PCM_HW_PARAM_CHANNELS)->min) #define params_rate(p) \ (hw_param_interval_c((p), SNDRV_PCM_HW_PARAM_RATE)->min) #define params_period_size(p) \ (hw_param_interval_c((p), SNDRV_PCM_HW_PARAM_PERIOD_SIZE)->min) #define params_periods(p) \ (hw_param_interval_c((p), SNDRV_PCM_HW_PARAM_PERIODS)->min) #define params_buffer_size(p) \ (hw_param_interval_c((p), SNDRV_PCM_HW_PARAM_BUFFER_SIZE)->min) #define params_buffer_bytes(p) \ (hw_param_interval_c((p), SNDRV_PCM_HW_PARAM_BUFFER_BYTES)->min) int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v); void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c); void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c); void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b, unsigned int k, struct snd_interval *c); void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k, const struct snd_interval *b, struct snd_interval *c); int snd_interval_list(struct snd_interval *i, unsigned int count, unsigned int *list, unsigned int mask); int snd_interval_ratnum(struct snd_interval *i, unsigned int rats_count, struct snd_ratnum *rats, unsigned int *nump, unsigned int *denp); void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params); void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params, snd_pcm_hw_param_t var); int snd_pcm_hw_params_choose(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params); int snd_pcm_hw_refine(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params); int snd_pcm_hw_constraints_init(struct snd_pcm_substream *substream); int snd_pcm_hw_constraints_complete(struct snd_pcm_substream *substream); int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var, u_int32_t mask); int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var, u_int64_t mask); int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var, unsigned int min, unsigned int max); int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var); int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime, unsigned int cond, snd_pcm_hw_param_t var, struct snd_pcm_hw_constraint_list *l); int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime, unsigned int cond, snd_pcm_hw_param_t var, struct snd_pcm_hw_constraint_ratnums *r); int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime, unsigned int cond, snd_pcm_hw_param_t var, struct snd_pcm_hw_constraint_ratdens *r); int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime, unsigned int cond, unsigned int width, unsigned int msbits); int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime, unsigned int cond, snd_pcm_hw_param_t var, unsigned long step); int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime, unsigned int cond, snd_pcm_hw_param_t var); int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime, unsigned int base_rate); int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond, int var, snd_pcm_hw_rule_func_t func, void *private, int dep, ...); int snd_pcm_format_signed(snd_pcm_format_t format); int snd_pcm_format_unsigned(snd_pcm_format_t format); int snd_pcm_format_linear(snd_pcm_format_t format); int snd_pcm_format_little_endian(snd_pcm_format_t format); int snd_pcm_format_big_endian(snd_pcm_format_t format); #if 0 /* just for DocBook */ /** * snd_pcm_format_cpu_endian - Check the PCM format is CPU-endian * @format: the format to check * * Returns 1 if the given PCM format is CPU-endian, 0 if * opposite, or a negative error code if endian not specified. */ int snd_pcm_format_cpu_endian(snd_pcm_format_t format); #endif /* DocBook */ #ifdef SNDRV_LITTLE_ENDIAN #define snd_pcm_format_cpu_endian(format) snd_pcm_format_little_endian(format) #else #define snd_pcm_format_cpu_endian(format) snd_pcm_format_big_endian(format) #endif int snd_pcm_format_width(snd_pcm_format_t format); /* in bits */ int snd_pcm_format_physical_width(snd_pcm_format_t format); /* in bits */ ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples); const unsigned char *snd_pcm_format_silence_64(snd_pcm_format_t format); int snd_pcm_format_set_silence(snd_pcm_format_t format, void *buf, unsigned int frames); snd_pcm_format_t snd_pcm_build_linear_format(int width, int unsignd, int big_endian); void snd_pcm_set_ops(struct snd_pcm * pcm, int direction, struct snd_pcm_ops *ops); void snd_pcm_set_sync(struct snd_pcm_substream *substream); int snd_pcm_lib_interleave_len(struct snd_pcm_substream *substream); int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream, unsigned int cmd, void *arg); int snd_pcm_update_state(struct snd_pcm_substream *substream, struct snd_pcm_runtime *runtime); int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream); int snd_pcm_playback_xrun_check(struct snd_pcm_substream *substream); int snd_pcm_capture_xrun_check(struct snd_pcm_substream *substream); int snd_pcm_playback_xrun_asap(struct snd_pcm_substream *substream); int snd_pcm_capture_xrun_asap(struct snd_pcm_substream *substream); void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr); void snd_pcm_period_elapsed(struct snd_pcm_substream *substream); snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t frames); snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t frames); snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream, void __user **bufs, snd_pcm_uframes_t frames); snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream, void __user **bufs, snd_pcm_uframes_t frames); extern const struct snd_pcm_hw_constraint_list snd_pcm_known_rates; int snd_pcm_limit_hw_rates(struct snd_pcm_runtime *runtime); unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate); static inline void snd_pcm_set_runtime_buffer(struct snd_pcm_substream *substream, struct snd_dma_buffer *bufp) { struct snd_pcm_runtime *runtime = substream->runtime; if (bufp) { runtime->dma_buffer_p = bufp; runtime->dma_area = bufp->area; runtime->dma_addr = bufp->addr; runtime->dma_bytes = bufp->bytes; } else { runtime->dma_buffer_p = NULL; runtime->dma_area = NULL; runtime->dma_addr = 0; runtime->dma_bytes = 0; } } /* * Timer interface */ void snd_pcm_timer_resolution_change(struct snd_pcm_substream *substream); void snd_pcm_timer_init(struct snd_pcm_substream *substream); void snd_pcm_timer_done(struct snd_pcm_substream *substream); static inline void snd_pcm_gettime(struct snd_pcm_runtime *runtime, struct timespec *tv) { if (runtime->tstamp_type == SNDRV_PCM_TSTAMP_TYPE_MONOTONIC) do_posix_clock_monotonic_gettime(tv); else getnstimeofday(tv); } /* * Memory */ int snd_pcm_lib_preallocate_free(struct snd_pcm_substream *substream); int snd_pcm_lib_preallocate_free_for_all(struct snd_pcm *pcm); int snd_pcm_lib_preallocate_pages(struct snd_pcm_substream *substream, int type, struct device *data, size_t size, size_t max); int snd_pcm_lib_preallocate_pages_for_all(struct snd_pcm *pcm, int type, void *data, size_t size, size_t max); int snd_pcm_lib_malloc_pages(struct snd_pcm_substream *substream, size_t size); int snd_pcm_lib_free_pages(struct snd_pcm_substream *substream); int _snd_pcm_lib_alloc_vmalloc_buffer(struct snd_pcm_substream *substream, size_t size, gfp_t gfp_flags); int snd_pcm_lib_free_vmalloc_buffer(struct snd_pcm_substream *substream); struct page *snd_pcm_lib_get_vmalloc_page(struct snd_pcm_substream *substream, unsigned long offset); #if 0 /* for kernel-doc */ /** * snd_pcm_lib_alloc_vmalloc_buffer - allocate virtual DMA buffer * @substream: the substream to allocate the buffer to * @size: the requested buffer size, in bytes * * Allocates the PCM substream buffer using vmalloc(), i.e., the memory is * contiguous in kernel virtual space, but not in physical memory. Use this * if the buffer is accessed by kernel code but not by device DMA. * * Returns 1 if the buffer was changed, 0 if not changed, or a negative error * code. */ static int snd_pcm_lib_alloc_vmalloc_buffer (struct snd_pcm_substream *substream, size_t size); /** * snd_pcm_lib_alloc_vmalloc_32_buffer - allocate 32-bit-addressable buffer * @substream: the substream to allocate the buffer to * @size: the requested buffer size, in bytes * * This function works like snd_pcm_lib_alloc_vmalloc_buffer(), but uses * vmalloc_32(), i.e., the pages are allocated from 32-bit-addressable memory. */ static int snd_pcm_lib_alloc_vmalloc_32_buffer (struct snd_pcm_substream *substream, size_t size); #endif #define snd_pcm_lib_alloc_vmalloc_buffer(subs, size) \ _snd_pcm_lib_alloc_vmalloc_buffer \ (subs, size, GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO) #define snd_pcm_lib_alloc_vmalloc_32_buffer(subs, size) \ _snd_pcm_lib_alloc_vmalloc_buffer \ (subs, size, GFP_KERNEL | GFP_DMA32 | __GFP_ZERO) #ifdef CONFIG_SND_DMA_SGBUF /* * SG-buffer handling */ #define snd_pcm_substream_sgbuf(substream) \ ((substream)->runtime->dma_buffer_p->private_data) static inline dma_addr_t snd_pcm_sgbuf_get_addr(struct snd_pcm_substream *substream, unsigned int ofs) { struct snd_sg_buf *sg = snd_pcm_substream_sgbuf(substream); return snd_sgbuf_get_addr(sg, ofs); } static inline void * snd_pcm_sgbuf_get_ptr(struct snd_pcm_substream *substream, unsigned int ofs) { struct snd_sg_buf *sg = snd_pcm_substream_sgbuf(substream); return snd_sgbuf_get_ptr(sg, ofs); } struct page *snd_pcm_sgbuf_ops_page(struct snd_pcm_substream *substream, unsigned long offset); unsigned int snd_pcm_sgbuf_get_chunk_size(struct snd_pcm_substream *substream, unsigned int ofs, unsigned int size); #else /* !SND_DMA_SGBUF */ /* * fake using a continuous buffer */ static inline dma_addr_t snd_pcm_sgbuf_get_addr(struct snd_pcm_substream *substream, unsigned int ofs) { return substream->runtime->dma_addr + ofs; } static inline void * snd_pcm_sgbuf_get_ptr(struct snd_pcm_substream *substream, unsigned int ofs) { return substream->runtime->dma_area + ofs; } #define snd_pcm_sgbuf_ops_page NULL #define snd_pcm_sgbuf_get_chunk_size(subs, ofs, size) (size) #endif /* SND_DMA_SGBUF */ /* handle mmap counter - PCM mmap callback should handle this counter properly */ static inline void snd_pcm_mmap_data_open(struct vm_area_struct *area) { struct snd_pcm_substream *substream = (struct snd_pcm_substream *)area->vm_private_data; atomic_inc(&substream->mmap_count); } static inline void snd_pcm_mmap_data_close(struct vm_area_struct *area) { struct snd_pcm_substream *substream = (struct snd_pcm_substream *)area->vm_private_data; atomic_dec(&substream->mmap_count); } int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream, struct vm_area_struct *area); /* mmap for io-memory area */ #if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_ALPHA) #define SNDRV_PCM_INFO_MMAP_IOMEM SNDRV_PCM_INFO_MMAP int snd_pcm_lib_mmap_iomem(struct snd_pcm_substream *substream, struct vm_area_struct *area); #else #define SNDRV_PCM_INFO_MMAP_IOMEM 0 #define snd_pcm_lib_mmap_iomem NULL #endif #define snd_pcm_lib_mmap_vmalloc NULL static inline void snd_pcm_limit_isa_dma_size(int dma, size_t *max) { *max = dma < 4 ? 64 * 1024 : 128 * 1024; } /* * Misc */ #define SNDRV_PCM_DEFAULT_CON_SPDIF (IEC958_AES0_CON_EMPHASIS_NONE|\ (IEC958_AES1_CON_ORIGINAL<<8)|\ (IEC958_AES1_CON_PCM_CODER<<8)|\ (IEC958_AES3_CON_FS_48000<<24)) #define PCM_RUNTIME_CHECK(sub) snd_BUG_ON(!(sub) || !(sub)->runtime) const char *snd_pcm_format_name(snd_pcm_format_t format); /* * PCM channel-mapping control API */ /* array element of channel maps */ struct snd_pcm_chmap_elem { unsigned char channels; unsigned char map[15]; }; /* channel map information; retrieved via snd_kcontrol_chip() */ struct snd_pcm_chmap { struct snd_pcm *pcm; /* assigned PCM instance */ int stream; /* PLAYBACK or CAPTURE */ struct snd_kcontrol *kctl; const struct snd_pcm_chmap_elem *chmap; unsigned int max_channels; unsigned int channel_mask; /* optional: active channels bitmask */ void *private_data; /* optional: private data pointer */ }; /* get the PCM substream assigned to the given chmap info */ static inline struct snd_pcm_substream * snd_pcm_chmap_substream(struct snd_pcm_chmap *info, unsigned int idx) { struct snd_pcm_substream *s; for (s = info->pcm->streams[info->stream].substream; s; s = s->next) if (s->number == idx) return s; return NULL; } /* ALSA-standard channel maps (RL/RR prior to C/LFE) */ extern const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[]; /* Other world's standard channel maps (C/LFE prior to RL/RR) */ extern const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[]; /* bit masks to be passed to snd_pcm_chmap.channel_mask field */ #define SND_PCM_CHMAP_MASK_24 ((1U << 2) | (1U << 4)) #define SND_PCM_CHMAP_MASK_246 (SND_PCM_CHMAP_MASK_24 | (1U << 6)) #define SND_PCM_CHMAP_MASK_2468 (SND_PCM_CHMAP_MASK_246 | (1U << 8)) int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream, const struct snd_pcm_chmap_elem *chmap, int max_channels, unsigned long private_value, struct snd_pcm_chmap **info_ret); /* * PCM Volume control API */ /* array element of volume */ struct snd_pcm_volume_elem { int volume; }; /* pp information; retrieved via snd_kcontrol_chip() */ struct snd_pcm_volume { struct snd_pcm *pcm; /* assigned PCM instance */ int stream; /* PLAYBACK or CAPTURE */ struct snd_kcontrol *kctl; const struct snd_pcm_volume_elem *volume; int max_length; void *private_data; /* optional: private data pointer */ }; int snd_pcm_add_volume_ctls(struct snd_pcm *pcm, int stream, const struct snd_pcm_volume_elem *volume, int max_length, unsigned long private_value, struct snd_pcm_volume **info_ret); #endif /* __SOUND_PCM_H */