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alsa-lib/src/pcm/pcm_hw.c
Jaroslav Kysela b9343e0834 - unified snd_pcm_hw_params_* functions 
- added backward compatibility for older non-compatible functions
- added --with-compat-rc3 to configure script to build library
  backwards compatible with 0.9.0rc3
- added symbol versioning like libc.so.6
  - ALSA_0.9      - alsa base
  - ALSA_0.9.0rc4 - first set of new functions (snd_pcm_hw_params_*)
2002-09-17 12:33:05 +00:00

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/**
* \file pcm/pcm_hw.c
* \ingroup PCM_Plugins
* \brief PCM HW Plugin Interface
* \author Abramo Bagnara <abramo@alsa-project.org>
* \author Jaroslav Kysela <perex@suse.cz>
* \date 2000-2001
*/
/*
* PCM - Hardware
* Copyright (c) 2000 by Abramo Bagnara <abramo@alsa-project.org>
*
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <unistd.h>
#include <signal.h>
#include <string.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/shm.h>
#include "pcm_local.h"
#include "../control/control_local.h"
//#define DEBUG_RW /* use to debug readi/writei/readn/writen */
//#define DEBUG_MMAP /* debug mmap_commit */
#ifndef PIC
/* entry for static linking */
const char *_snd_module_pcm_hw = "";
#endif
#ifndef DOC_HIDDEN
#ifndef F_SETSIG
#define F_SETSIG 10
#endif
/*
* Compatibility
*/
struct sndrv_pcm_hw_params_old {
unsigned int flags;
unsigned int masks[SNDRV_PCM_HW_PARAM_SUBFORMAT -
SNDRV_PCM_HW_PARAM_ACCESS + 1];
struct sndrv_interval intervals[SNDRV_PCM_HW_PARAM_TICK_TIME -
SNDRV_PCM_HW_PARAM_SAMPLE_BITS + 1];
unsigned int rmask;
unsigned int cmask;
unsigned int info;
unsigned int msbits;
unsigned int rate_num;
unsigned int rate_den;
sndrv_pcm_uframes_t fifo_size;
unsigned char reserved[64];
};
#define SND_PCM_IOCTL_HW_REFINE_OLD _IOWR('A', 0x10, struct sndrv_pcm_hw_params_old)
#define SND_PCM_IOCTL_HW_PARAMS_OLD _IOWR('A', 0x11, struct sndrv_pcm_hw_params_old)
#define SND_PCM_IOCTL_XRUN _IO('A', 0x48)
static int use_old_hw_params_ioctl(int fd, unsigned int cmd, snd_pcm_hw_params_t *params);
/*
*
*/
typedef struct {
int version;
int fd;
int card, device, subdevice;
int mmap_emulation;
volatile struct sndrv_pcm_mmap_status * mmap_status;
struct sndrv_pcm_mmap_control *mmap_control;
int shadow_appl_ptr: 1,
avail_update_flag: 1,
mmap_shm: 1;
snd_pcm_uframes_t appl_ptr;
int shmid;
} snd_pcm_hw_t;
#define SNDRV_FILE_PCM_STREAM_PLAYBACK "/dev/snd/pcmC%iD%ip"
#define SNDRV_FILE_PCM_STREAM_CAPTURE "/dev/snd/pcmC%iD%ic"
#define SNDRV_PCM_VERSION_MAX SNDRV_PROTOCOL_VERSION(2, 0, 2)
/* update appl_ptr with driver */
#define UPDATE_SHADOW_PTR(hw) \
do { if (hw->shadow_appl_ptr && !hw->avail_update_flag) \
hw->appl_ptr = hw->mmap_control->appl_ptr; } while (0)
#define FAST_PCM_STATE(hw) \
((enum sndrv_pcm_state) (hw)->mmap_status->state)
#endif /* DOC_HIDDEN */
static int snd_pcm_hw_nonblock(snd_pcm_t *pcm, int nonblock)
{
long flags;
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
if ((flags = fcntl(fd, F_GETFL)) < 0) {
SYSERR("F_GETFL failed");
return -errno;
}
if (nonblock)
flags |= O_NONBLOCK;
else
flags &= ~O_NONBLOCK;
if (fcntl(fd, F_SETFL, flags) < 0) {
SYSERR("F_SETFL for O_NONBLOCK failed");
return -errno;
}
return 0;
}
static int snd_pcm_hw_async(snd_pcm_t *pcm, int sig, pid_t pid)
{
long flags;
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
if ((flags = fcntl(fd, F_GETFL)) < 0) {
SYSERR("F_GETFL failed");
return -errno;
}
if (sig >= 0)
flags |= O_ASYNC;
else
flags &= ~O_ASYNC;
if (fcntl(fd, F_SETFL, flags) < 0) {
SYSERR("F_SETFL for O_ASYNC failed");
return -errno;
}
if (sig < 0)
return 0;
if (fcntl(fd, F_SETSIG, (long)sig) < 0) {
SYSERR("F_SETSIG failed");
return -errno;
}
if (fcntl(fd, F_SETOWN, (long)pid) < 0) {
SYSERR("F_SETOWN failed");
return -errno;
}
return 0;
}
static int snd_pcm_hw_info(snd_pcm_t *pcm, snd_pcm_info_t * info)
{
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
if (ioctl(fd, SNDRV_PCM_IOCTL_INFO, info) < 0) {
SYSERR("SNDRV_PCM_IOCTL_INFO failed");
return -errno;
}
return 0;
}
static inline int hw_refine_call(snd_pcm_hw_t *pcm_hw, snd_pcm_hw_params_t *params)
{
/* check for new hw_params structure; it's available from 2.0.2 version of PCM API */
if (SNDRV_PROTOCOL_VERSION(2, 0, 2) <= pcm_hw->version)
return ioctl(pcm_hw->fd, SNDRV_PCM_IOCTL_HW_REFINE, params);
return use_old_hw_params_ioctl(pcm_hw->fd, SND_PCM_IOCTL_HW_REFINE_OLD, params);
}
static int snd_pcm_hw_hw_refine(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)
{
snd_pcm_hw_t *hw = pcm->private_data;
if (hw->mmap_emulation) {
int err = 0;
snd_pcm_access_mask_t oldmask = *snd_pcm_hw_param_get_mask(params, SND_PCM_HW_PARAM_ACCESS);
snd_pcm_access_mask_t mask;
const snd_mask_t *pmask;
snd_mask_empty(&mask);
if (hw_refine_call(hw, params) < 0)
err = -errno;
if (err < 0) {
snd_pcm_hw_params_t new = *params;
if (snd_pcm_access_mask_test(&oldmask, SND_PCM_ACCESS_MMAP_INTERLEAVED) &&
!snd_pcm_access_mask_test(&oldmask, SND_PCM_ACCESS_RW_INTERLEAVED))
snd_pcm_access_mask_set(&mask, SND_PCM_ACCESS_RW_INTERLEAVED);
if (snd_pcm_access_mask_test(&oldmask, SND_PCM_ACCESS_MMAP_NONINTERLEAVED) &&
!snd_pcm_access_mask_test(&oldmask, SND_PCM_ACCESS_RW_NONINTERLEAVED))
snd_pcm_access_mask_set(&mask, SND_PCM_ACCESS_RW_NONINTERLEAVED);
if (snd_pcm_access_mask_empty(&mask))
return err;
pmask = snd_pcm_hw_param_get_mask(&new, SND_PCM_HW_PARAM_ACCESS);
*(snd_mask_t *)pmask = mask;
if (hw_refine_call(hw, &new) < 0)
return -errno;
*params = new;
}
pmask = snd_pcm_hw_param_get_mask(params, SND_PCM_HW_PARAM_ACCESS);
if (snd_pcm_access_mask_test(pmask, SND_PCM_ACCESS_MMAP_INTERLEAVED) ||
snd_pcm_access_mask_test(pmask, SND_PCM_ACCESS_MMAP_NONINTERLEAVED) ||
snd_pcm_access_mask_test(pmask, SND_PCM_ACCESS_MMAP_COMPLEX))
return 0;
if (snd_pcm_access_mask_test(&mask, SND_PCM_ACCESS_RW_INTERLEAVED)) {
if (snd_pcm_access_mask_test(pmask, SND_PCM_ACCESS_RW_INTERLEAVED))
snd_pcm_access_mask_set((snd_pcm_access_mask_t *)pmask, SND_PCM_ACCESS_MMAP_INTERLEAVED);
snd_pcm_access_mask_reset((snd_pcm_access_mask_t *)pmask, SND_PCM_ACCESS_RW_INTERLEAVED);
}
if (snd_pcm_access_mask_test(&mask, SND_PCM_ACCESS_RW_NONINTERLEAVED)) {
if (snd_pcm_access_mask_test(pmask, SND_PCM_ACCESS_RW_NONINTERLEAVED))
snd_pcm_access_mask_set((snd_pcm_access_mask_t *)pmask, SND_PCM_ACCESS_MMAP_NONINTERLEAVED);
snd_pcm_access_mask_reset((snd_pcm_access_mask_t *)pmask, SND_PCM_ACCESS_RW_NONINTERLEAVED);
}
if (snd_pcm_access_mask_test(&oldmask, SND_PCM_ACCESS_MMAP_INTERLEAVED)) {
if (snd_pcm_access_mask_test(&oldmask, SND_PCM_ACCESS_RW_INTERLEAVED)) {
if (snd_pcm_access_mask_test(pmask, SND_PCM_ACCESS_RW_INTERLEAVED))
snd_pcm_access_mask_set((snd_pcm_access_mask_t *)pmask, SND_PCM_ACCESS_MMAP_INTERLEAVED);
}
}
if (snd_pcm_access_mask_test(&oldmask, SND_PCM_ACCESS_MMAP_NONINTERLEAVED)) {
if (snd_pcm_access_mask_test(&oldmask, SND_PCM_ACCESS_RW_NONINTERLEAVED)) {
if (snd_pcm_access_mask_test(pmask, SND_PCM_ACCESS_RW_NONINTERLEAVED))
snd_pcm_access_mask_set((snd_pcm_access_mask_t *)pmask, SND_PCM_ACCESS_MMAP_NONINTERLEAVED);
}
}
} else {
if (hw_refine_call(hw, params) < 0) {
// SYSERR("SNDRV_PCM_IOCTL_HW_REFINE failed");
return -errno;
}
}
return 0;
}
static inline int hw_params_call(snd_pcm_hw_t *pcm_hw, snd_pcm_hw_params_t *params)
{
/* check for new hw_params structure; it's available from 2.0.2 version of PCM API */
if (SNDRV_PROTOCOL_VERSION(2, 0, 2) <= pcm_hw->version)
return ioctl(pcm_hw->fd, SNDRV_PCM_IOCTL_HW_PARAMS, params);
return use_old_hw_params_ioctl(pcm_hw->fd, SND_PCM_IOCTL_HW_PARAMS_OLD, params);
}
static int snd_pcm_hw_hw_params(snd_pcm_t *pcm, snd_pcm_hw_params_t * params)
{
snd_pcm_hw_t *hw = pcm->private_data;
if (hw->mmap_emulation) {
snd_pcm_hw_params_t old = *params;
if (hw_params_call(hw, params) < 0) {
snd_pcm_access_t access;
snd_pcm_access_mask_t oldmask;
const snd_mask_t *pmask;
*params = old;
pmask = snd_pcm_hw_param_get_mask(params, SND_PCM_HW_PARAM_ACCESS);
oldmask = *(snd_pcm_access_mask_t *)pmask;
if (INTERNAL(snd_pcm_hw_params_get_access)(params, &access) < 0)
goto _err;
switch (access) {
case SND_PCM_ACCESS_MMAP_INTERLEAVED:
snd_pcm_access_mask_reset((snd_pcm_access_mask_t *)pmask, SND_PCM_ACCESS_MMAP_INTERLEAVED);
snd_pcm_access_mask_set((snd_pcm_access_mask_t *)pmask, SND_PCM_ACCESS_RW_INTERLEAVED);
break;
case SND_PCM_ACCESS_MMAP_NONINTERLEAVED:
snd_pcm_access_mask_reset((snd_pcm_access_mask_t *)pmask, SND_PCM_ACCESS_MMAP_NONINTERLEAVED);
snd_pcm_access_mask_set((snd_pcm_access_mask_t *)pmask, SND_PCM_ACCESS_RW_NONINTERLEAVED);
break;
default:
goto _err;
}
if (hw_params_call(hw, params) < 0)
goto _err;
hw->mmap_shm = 1;
*(snd_pcm_access_mask_t *)pmask = oldmask;
}
} else {
if (hw_params_call(hw, params) < 0) {
_err:
SYSERR("SNDRV_PCM_IOCTL_HW_PARAMS failed");
return -errno;
}
}
if (pcm->stream == SND_PCM_STREAM_CAPTURE) {
if (hw->mmap_shm) {
hw->shadow_appl_ptr = 1;
hw->appl_ptr = 0;
snd_pcm_set_appl_ptr(pcm, &hw->appl_ptr, -1, 0);
} else {
hw->shadow_appl_ptr = 0;
snd_pcm_set_appl_ptr(pcm, &hw->mmap_control->appl_ptr, hw->fd, SNDRV_PCM_MMAP_OFFSET_CONTROL);
}
}
return 0;
}
static int snd_pcm_hw_hw_free(snd_pcm_t *pcm)
{
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
if (ioctl(fd, SNDRV_PCM_IOCTL_HW_FREE) < 0) {
SYSERR("SNDRV_PCM_IOCTL_HW_FREE failed");
return -errno;
}
return 0;
}
static int snd_pcm_hw_sw_params(snd_pcm_t *pcm, snd_pcm_sw_params_t * params)
{
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
if ((snd_pcm_tstamp_t) params->tstamp_mode == pcm->tstamp_mode &&
params->period_step == pcm->period_step &&
params->sleep_min == pcm->sleep_min &&
params->xfer_align == pcm->xfer_align &&
params->start_threshold == pcm->start_threshold &&
params->stop_threshold == pcm->stop_threshold &&
params->silence_threshold == pcm->silence_threshold &&
params->silence_size == pcm->silence_size) {
hw->mmap_control->avail_min = params->avail_min;
return 0;
}
if (ioctl(fd, SNDRV_PCM_IOCTL_SW_PARAMS, params) < 0) {
SYSERR("SNDRV_PCM_IOCTL_SW_PARAMS failed");
return -errno;
}
return 0;
}
static int snd_pcm_hw_channel_info(snd_pcm_t *pcm, snd_pcm_channel_info_t * info)
{
snd_pcm_hw_t *hw = pcm->private_data;
struct sndrv_pcm_channel_info i;
int fd = hw->fd;
i.channel = info->channel;
if (ioctl(fd, SNDRV_PCM_IOCTL_CHANNEL_INFO, &i) < 0) {
SYSERR("SNDRV_PCM_IOCTL_CHANNEL_INFO failed");
return -errno;
}
info->channel = i.channel;
if (!hw->mmap_shm) {
info->addr = 0;
info->first = i.first;
info->step = i.step;
info->type = SND_PCM_AREA_MMAP;
info->u.mmap.fd = fd;
info->u.mmap.offset = i.offset;
return 0;
}
return snd_pcm_channel_info_shm(pcm, info, hw->shmid);
}
static int snd_pcm_hw_status(snd_pcm_t *pcm, snd_pcm_status_t * status)
{
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
if (ioctl(fd, SNDRV_PCM_IOCTL_STATUS, status) < 0) {
SYSERR("SNDRV_PCM_IOCTL_STATUS failed");
return -errno;
}
return 0;
}
static snd_pcm_state_t snd_pcm_hw_state(snd_pcm_t *pcm)
{
snd_pcm_hw_t *hw = pcm->private_data;
return (snd_pcm_state_t) hw->mmap_status->state;
}
static int snd_pcm_hw_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delayp)
{
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
if (ioctl(fd, SNDRV_PCM_IOCTL_DELAY, delayp) < 0) {
// SYSERR("SNDRV_PCM_IOCTL_DELAY failed");
return -errno;
}
return 0;
}
static int snd_pcm_hw_prepare(snd_pcm_t *pcm)
{
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
if (ioctl(fd, SNDRV_PCM_IOCTL_PREPARE) < 0) {
SYSERR("SNDRV_PCM_IOCTL_PREPARE failed");
return -errno;
}
return 0;
}
static int snd_pcm_hw_reset(snd_pcm_t *pcm)
{
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
if (ioctl(fd, SNDRV_PCM_IOCTL_RESET) < 0) {
SYSERR("SNDRV_PCM_IOCTL_RESET failed");
return -errno;
}
return 0;
}
static int snd_pcm_hw_start(snd_pcm_t *pcm)
{
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
#if 0
assert(pcm->stream != SND_PCM_STREAM_PLAYBACK ||
snd_pcm_mmap_playback_hw_avail(pcm) > 0);
#endif
if (ioctl(fd, SNDRV_PCM_IOCTL_START) < 0) {
SYSERR("SNDRV_PCM_IOCTL_START failed");
#if 0
if (errno == EBADFD)
SNDERR("PCM state = %s", snd_pcm_state_name(snd_pcm_hw_state(pcm)));
#endif
return -errno;
}
return 0;
}
static int snd_pcm_hw_drop(snd_pcm_t *pcm)
{
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
if (ioctl(fd, SNDRV_PCM_IOCTL_DROP) < 0) {
SYSERR("SNDRV_PCM_IOCTL_DROP failed");
return -errno;
}
return 0;
}
static int snd_pcm_hw_drain(snd_pcm_t *pcm)
{
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
if (ioctl(fd, SNDRV_PCM_IOCTL_DRAIN) < 0) {
if (errno != EAGAIN)
SYSERR("SNDRV_PCM_IOCTL_DRAIN failed");
return -errno;
}
return 0;
}
static int snd_pcm_hw_pause(snd_pcm_t *pcm, int enable)
{
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
if (ioctl(fd, SNDRV_PCM_IOCTL_PAUSE, enable) < 0) {
SYSERR("SNDRV_PCM_IOCTL_PAUSE failed");
return -errno;
}
return 0;
}
static snd_pcm_sframes_t snd_pcm_hw_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
{
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
if (ioctl(fd, SNDRV_PCM_IOCTL_REWIND, &frames) < 0) {
SYSERR("SNDRV_PCM_IOCTL_REWIND failed");
return -errno;
}
return frames;
}
static int snd_pcm_hw_resume(snd_pcm_t *pcm)
{
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
if (ioctl(fd, SNDRV_PCM_IOCTL_RESUME) < 0) {
if (errno != ENXIO && errno != ENOSYS)
SYSERR("SNDRV_PCM_IOCTL_RESUME failed");
return -errno;
}
return 0;
}
static snd_pcm_sframes_t snd_pcm_hw_writei(snd_pcm_t *pcm, const void *buffer, snd_pcm_uframes_t size)
{
int result;
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
struct sndrv_xferi xferi;
xferi.buf = (char*) buffer;
xferi.frames = size;
result = ioctl(fd, SNDRV_PCM_IOCTL_WRITEI_FRAMES, &xferi);
#ifdef DEBUG_RW
fprintf(stderr, "hw_writei: frames = %li, result = %i, result = %li\n", size, result, xferi.result);
#endif
if (result < 0)
return -errno;
return xferi.result;
}
static snd_pcm_sframes_t snd_pcm_hw_writen(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size)
{
int result;
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
struct sndrv_xfern xfern;
xfern.bufs = bufs;
xfern.frames = size;
result = ioctl(fd, SNDRV_PCM_IOCTL_WRITEN_FRAMES, &xfern);
#ifdef DEBUG_RW
fprintf(stderr, "hw_writen: frames = %li, result = %i, result = %li\n", size, result, xfern.result);
#endif
if (result < 0)
return -errno;
return xfern.result;
}
static snd_pcm_sframes_t snd_pcm_hw_readi(snd_pcm_t *pcm, void *buffer, snd_pcm_uframes_t size)
{
int result;
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
struct sndrv_xferi xferi;
xferi.buf = buffer;
xferi.frames = size;
result = ioctl(fd, SNDRV_PCM_IOCTL_READI_FRAMES, &xferi);
#ifdef DEBUG_RW
fprintf(stderr, "hw_readi: frames = %li, result = %i, result = %li\n", size, result, xferi.result);
#endif
if (result < 0)
return -errno;
UPDATE_SHADOW_PTR(hw);
return xferi.result;
}
static snd_pcm_sframes_t snd_pcm_hw_readn(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size)
{
int result;
snd_pcm_hw_t *hw = pcm->private_data;
int fd = hw->fd;
struct sndrv_xfern xfern;
xfern.bufs = bufs;
xfern.frames = size;
result = ioctl(fd, SNDRV_PCM_IOCTL_READN_FRAMES, &xfern);
#ifdef DEBUG_RW
fprintf(stderr, "hw_readn: frames = %li, result = %i, result = %li\n", size, result, xfern.result);
#endif
if (result < 0)
return -errno;
UPDATE_SHADOW_PTR(hw);
return xfern.result;
}
static int snd_pcm_hw_mmap_status(snd_pcm_t *pcm)
{
snd_pcm_hw_t *hw = pcm->private_data;
void *ptr;
ptr = mmap(NULL, page_align(sizeof(struct sndrv_pcm_mmap_status)),
PROT_READ, MAP_FILE|MAP_SHARED,
hw->fd, SNDRV_PCM_MMAP_OFFSET_STATUS);
if (ptr == MAP_FAILED || ptr == NULL) {
SYSERR("status mmap failed");
return -errno;
}
hw->mmap_status = ptr;
snd_pcm_set_hw_ptr(pcm, &hw->mmap_status->hw_ptr, hw->fd, SNDRV_PCM_MMAP_OFFSET_STATUS + offsetof(struct sndrv_pcm_mmap_status, hw_ptr));
return 0;
}
static int snd_pcm_hw_mmap_control(snd_pcm_t *pcm)
{
snd_pcm_hw_t *hw = pcm->private_data;
void *ptr;
ptr = mmap(NULL, page_align(sizeof(struct sndrv_pcm_mmap_control)),
PROT_READ|PROT_WRITE, MAP_FILE|MAP_SHARED,
hw->fd, SNDRV_PCM_MMAP_OFFSET_CONTROL);
if (ptr == MAP_FAILED || ptr == NULL) {
SYSERR("control mmap failed");
return -errno;
}
hw->mmap_control = ptr;
snd_pcm_set_appl_ptr(pcm, &hw->mmap_control->appl_ptr, hw->fd, SNDRV_PCM_MMAP_OFFSET_CONTROL);
return 0;
}
static int snd_pcm_hw_munmap_status(snd_pcm_t *pcm)
{
snd_pcm_hw_t *hw = pcm->private_data;
if (munmap((void*)hw->mmap_status, page_align(sizeof(*hw->mmap_status))) < 0) {
SYSERR("status munmap failed");
return -errno;
}
return 0;
}
static int snd_pcm_hw_munmap_control(snd_pcm_t *pcm)
{
snd_pcm_hw_t *hw = pcm->private_data;
if (munmap(hw->mmap_control, page_align(sizeof(*hw->mmap_control))) < 0) {
SYSERR("control munmap failed");
return -errno;
}
return 0;
}
static int snd_pcm_hw_mmap(snd_pcm_t *pcm)
{
snd_pcm_hw_t *hw = pcm->private_data;
if (hw->mmap_shm) {
snd_pcm_uframes_t size = snd_pcm_frames_to_bytes(pcm, (snd_pcm_sframes_t) pcm->buffer_size);
int id = shmget(IPC_PRIVATE, size, 0666);
hw->mmap_shm = 1;
if (id < 0) {
SYSERR("shmget failed");
return -errno;
}
hw->shmid = id;
}
return 0;
}
static int snd_pcm_hw_munmap(snd_pcm_t *pcm)
{
snd_pcm_hw_t *hw = pcm->private_data;
if (hw->mmap_shm) {
if (shmctl(hw->shmid, IPC_RMID, 0) < 0) {
SYSERR("shmctl IPC_RMID failed");
return -errno;
}
}
return 0;
}
static int snd_pcm_hw_close(snd_pcm_t *pcm)
{
snd_pcm_hw_t *hw = pcm->private_data;
if (close(hw->fd)) {
SYSERR("close failed\n");
return -errno;
}
snd_pcm_hw_munmap_status(pcm);
snd_pcm_hw_munmap_control(pcm);
free(hw);
return 0;
}
static snd_pcm_sframes_t snd_pcm_hw_mmap_commit(snd_pcm_t *pcm,
snd_pcm_uframes_t offset ATTRIBUTE_UNUSED,
snd_pcm_uframes_t size)
{
snd_pcm_hw_t *hw = pcm->private_data;
if (hw->mmap_shm) {
if (pcm->stream == SND_PCM_STREAM_PLAYBACK) {
snd_pcm_sframes_t result = 0, res;
do {
res = snd_pcm_write_mmap(pcm, size);
if (res < 0)
return result > 0 ? result : res;
size -= res;
result += res;
} while (size > 0);
return result;
} else {
snd_pcm_hw_t *hw = pcm->private_data;
assert(hw->shadow_appl_ptr);
}
}
snd_pcm_mmap_appl_forward(pcm, size);
#ifdef DEBUG_MMAP
fprintf(stderr, "appl_forward: hw_ptr = %li, appl_ptr = %li, size = %li\n", *pcm->hw_ptr, *pcm->appl_ptr, size);
#endif
return size;
}
static snd_pcm_sframes_t snd_pcm_hw_avail_update(snd_pcm_t *pcm)
{
snd_pcm_hw_t *hw = pcm->private_data;
snd_pcm_uframes_t avail;
if (pcm->stream == SND_PCM_STREAM_PLAYBACK) {
avail = snd_pcm_mmap_playback_avail(pcm);
} else {
avail = snd_pcm_mmap_capture_avail(pcm);
if (avail > 0 && hw->mmap_shm) {
snd_pcm_sframes_t err;
snd_pcm_hw_t *hw = pcm->private_data;
hw->avail_update_flag = 1;
err = snd_pcm_read_mmap(pcm, avail);
hw->avail_update_flag = 0;
if (err < 0)
return err;
assert((snd_pcm_uframes_t)err == avail);
return err;
}
}
switch (FAST_PCM_STATE(hw)) {
case SNDRV_PCM_STATE_RUNNING:
if (avail >= pcm->stop_threshold) {
/* SNDRV_PCM_IOCTL_XRUN ioctl has been implemented since PCM kernel API 2.0.1 */
if (SNDRV_PROTOCOL_VERSION(2, 0, 1) <= hw->version) {
if (ioctl(hw->fd, SND_PCM_IOCTL_XRUN) < 0)
return -errno;
}
/* everything is ok, state == SND_PCM_STATE_XRUN at the moment */
return -EPIPE;
}
break;
case SNDRV_PCM_STATE_XRUN:
return -EPIPE;
default:
break;
}
return avail;
}
static void snd_pcm_hw_dump(snd_pcm_t *pcm, snd_output_t *out)
{
snd_pcm_hw_t *hw = pcm->private_data;
char *name;
int err = snd_card_get_name(hw->card, &name);
assert(err >= 0);
snd_output_printf(out, "Hardware PCM card %d '%s' device %d subdevice %d\n",
hw->card, name, hw->device, hw->subdevice);
free(name);
if (pcm->setup) {
snd_output_printf(out, "\nIts setup is:\n");
snd_pcm_dump_setup(pcm, out);
}
}
static snd_pcm_ops_t snd_pcm_hw_ops = {
close: snd_pcm_hw_close,
info: snd_pcm_hw_info,
hw_refine: snd_pcm_hw_hw_refine,
hw_params: snd_pcm_hw_hw_params,
hw_free: snd_pcm_hw_hw_free,
sw_params: snd_pcm_hw_sw_params,
channel_info: snd_pcm_hw_channel_info,
dump: snd_pcm_hw_dump,
nonblock: snd_pcm_hw_nonblock,
async: snd_pcm_hw_async,
mmap: snd_pcm_hw_mmap,
munmap: snd_pcm_hw_munmap,
};
static snd_pcm_fast_ops_t snd_pcm_hw_fast_ops = {
status: snd_pcm_hw_status,
state: snd_pcm_hw_state,
delay: snd_pcm_hw_delay,
prepare: snd_pcm_hw_prepare,
reset: snd_pcm_hw_reset,
start: snd_pcm_hw_start,
drop: snd_pcm_hw_drop,
drain: snd_pcm_hw_drain,
pause: snd_pcm_hw_pause,
rewind: snd_pcm_hw_rewind,
resume: snd_pcm_hw_resume,
writei: snd_pcm_hw_writei,
writen: snd_pcm_hw_writen,
readi: snd_pcm_hw_readi,
readn: snd_pcm_hw_readn,
avail_update: snd_pcm_hw_avail_update,
mmap_commit: snd_pcm_hw_mmap_commit,
};
/**
* \brief Creates a new hw PCM
* \param pcmp Returns created PCM handle
* \param name Name of PCM
* \param card Number of card
* \param device Number of device
* \param subdevice Number of subdevice
* \param stream PCM Stream
* \param mode PCM Mode
* \retval zero on success otherwise a negative error code
* \warning Using of this function might be dangerous in the sense
* of compatibility reasons. The prototype might be freely
* changed in future.
*/
int snd_pcm_hw_open(snd_pcm_t **pcmp, const char *name,
int card, int device, int subdevice,
snd_pcm_stream_t stream, int mode,
int mmap_emulation)
{
char filename[32];
const char *filefmt;
int ver;
int err, ret = 0, fd = -1;
int attempt = 0;
snd_pcm_info_t info;
int fmode;
snd_ctl_t *ctl;
snd_pcm_t *pcm = NULL;
snd_pcm_hw_t *hw = NULL;
assert(pcmp);
if ((ret = snd_ctl_hw_open(&ctl, NULL, card, 0)) < 0)
return ret;
switch (stream) {
case SND_PCM_STREAM_PLAYBACK:
filefmt = SNDRV_FILE_PCM_STREAM_PLAYBACK;
break;
case SND_PCM_STREAM_CAPTURE:
filefmt = SNDRV_FILE_PCM_STREAM_CAPTURE;
break;
default:
assert(0);
}
sprintf(filename, filefmt, card, device);
__again:
if (attempt++ > 3) {
ret = -EBUSY;
goto _err;
}
ret = snd_ctl_pcm_prefer_subdevice(ctl, subdevice);
if (ret < 0)
goto _err;
fmode = O_RDWR;
if (mode & SND_PCM_NONBLOCK)
fmode |= O_NONBLOCK;
if (mode & SND_PCM_ASYNC)
fmode |= O_ASYNC;
if ((fd = open(filename, fmode)) < 0) {
SYSERR("open %s failed", filename);
ret = -errno;
goto _err;
}
if (ioctl(fd, SNDRV_PCM_IOCTL_PVERSION, &ver) < 0) {
SYSERR("SNDRV_PCM_IOCTL_PVERSION failed");
ret = -errno;
goto _err;
}
if (SNDRV_PROTOCOL_INCOMPATIBLE(ver, SNDRV_PCM_VERSION_MAX)) {
ret = -SND_ERROR_INCOMPATIBLE_VERSION;
goto _err;
}
if (subdevice >= 0) {
memset(&info, 0, sizeof(info));
if (ioctl(fd, SNDRV_PCM_IOCTL_INFO, &info) < 0) {
SYSERR("SNDRV_PCM_IOCTL_INFO failed");
ret = -errno;
goto _err;
}
if (info.subdevice != (unsigned int) subdevice) {
close(fd);
goto __again;
}
}
hw = calloc(1, sizeof(snd_pcm_hw_t));
if (!hw) {
ret = -ENOMEM;
goto _err;
}
hw->version = ver;
hw->card = card;
hw->device = device;
hw->subdevice = subdevice;
hw->fd = fd;
hw->mmap_emulation = mmap_emulation;
err = snd_pcm_new(&pcm, SND_PCM_TYPE_HW, name, stream, mode);
if (err < 0) {
ret = err;
goto _err;
}
snd_ctl_close(ctl);
pcm->ops = &snd_pcm_hw_ops;
pcm->fast_ops = &snd_pcm_hw_fast_ops;
pcm->private_data = hw;
pcm->poll_fd = fd;
*pcmp = pcm;
ret = snd_pcm_hw_mmap_status(pcm);
if (ret < 0) {
snd_pcm_close(pcm);
return ret;
}
ret = snd_pcm_hw_mmap_control(pcm);
if (ret < 0) {
snd_pcm_close(pcm);
return ret;
}
return 0;
_err:
if (hw)
free(hw);
if (pcm)
free(pcm);
if (fd >= 0)
close(fd);
snd_ctl_close(ctl);
return ret;
}
/*! \page pcm_plugins
\section pcm_plugins_hw Plugin: hw
This plugin communicates directly with the ALSA kernel driver. It is a raw
communication without any conversions. The emulation of mmap access can be
optionally enabled, but expect worse latency in the case.
\code
pcm.name {
type hw # Kernel PCM
card INT/STR # Card name (string) or number (integer)
[device INT] # Device number (default 0)
[subdevice INT] # Subdevice number (default -1: first available)
[mmap_emulation BOOL] # Enable mmap emulation for ro/wo devices
}
\endcode
\subsection pcm_plugins_hw_funcref Function reference
<UL>
<LI>snd_pcm_hw_open()
<LI>_snd_pcm_hw_open()
</UL>
*/
/**
* \brief Creates a new hw PCM
* \param pcmp Returns created PCM handle
* \param name Name of PCM
* \param root Root configuration node
* \param conf Configuration node with hw PCM description
* \param stream PCM Stream
* \param mode PCM Mode
* \warning Using of this function might be dangerous in the sense
* of compatibility reasons. The prototype might be freely
* changed in future.
*/
int _snd_pcm_hw_open(snd_pcm_t **pcmp, const char *name,
snd_config_t *root ATTRIBUTE_UNUSED, snd_config_t *conf,
snd_pcm_stream_t stream, int mode)
{
snd_config_iterator_t i, next;
long card = -1, device = 0, subdevice = -1;
const char *str;
int err, mmap_emulation = 0;
snd_config_for_each(i, next, conf) {
snd_config_t *n = snd_config_iterator_entry(i);
const char *id;
if (snd_config_get_id(n, &id) < 0)
continue;
if (snd_pcm_conf_generic_id(id))
continue;
if (strcmp(id, "card") == 0) {
err = snd_config_get_integer(n, &card);
if (err < 0) {
err = snd_config_get_string(n, &str);
if (err < 0) {
SNDERR("Invalid type for %s", id);
return -EINVAL;
}
card = snd_card_get_index(str);
if (card < 0) {
SNDERR("Invalid value for %s", id);
return card;
}
}
continue;
}
if (strcmp(id, "device") == 0) {
err = snd_config_get_integer(n, &device);
if (err < 0) {
SNDERR("Invalid type for %s", id);
return err;
}
continue;
}
if (strcmp(id, "subdevice") == 0) {
err = snd_config_get_integer(n, &subdevice);
if (err < 0) {
SNDERR("Invalid type for %s", id);
return err;
}
continue;
}
if (strcmp(id, "mmap_emulation") == 0) {
err = snd_config_get_bool(n);
if (err < 0)
continue;
mmap_emulation = err;
continue;
}
SNDERR("Unknown field %s", id);
return -EINVAL;
}
if (card < 0) {
SNDERR("card is not defined");
return -EINVAL;
}
return snd_pcm_hw_open(pcmp, name, card, device, subdevice, stream, mode, mmap_emulation);
}
#ifndef DOC_HIDDEN
SND_DLSYM_BUILD_VERSION(_snd_pcm_hw_open, SND_PCM_DLSYM_VERSION);
#endif
/*
* To be removed helpers, but keep binary compatibility at the time
*/
#define __OLD_TO_NEW_MASK(x) ((x&7)|((x&0x07fffff8)<<5))
#define __NEW_TO_OLD_MASK(x) ((x&7)|((x&0xffffff00)>>5))
static void snd_pcm_hw_convert_from_old_params(snd_pcm_hw_params_t *params,
struct sndrv_pcm_hw_params_old *oparams)
{
unsigned int i;
memset(params, 0, sizeof(*params));
params->flags = oparams->flags;
for (i = 0; i < sizeof(oparams->masks) / sizeof(unsigned int); i++)
params->masks[i].bits[0] = oparams->masks[i];
memcpy(params->intervals, oparams->intervals, sizeof(oparams->intervals));
params->rmask = __OLD_TO_NEW_MASK(oparams->rmask);
params->cmask = __OLD_TO_NEW_MASK(oparams->cmask);
params->info = oparams->info;
params->msbits = oparams->msbits;
params->rate_num = oparams->rate_num;
params->rate_den = oparams->rate_den;
params->fifo_size = oparams->fifo_size;
}
static void snd_pcm_hw_convert_to_old_params(struct sndrv_pcm_hw_params_old *oparams,
snd_pcm_hw_params_t *params,
unsigned int *cmask)
{
unsigned int i, j;
memset(oparams, 0, sizeof(*oparams));
oparams->flags = params->flags;
for (i = 0; i < sizeof(oparams->masks) / sizeof(unsigned int); i++) {
oparams->masks[i] = params->masks[i].bits[0];
for (j = 1; j < sizeof(params->masks[i].bits) / sizeof(unsigned int); j++)
if (params->masks[i].bits[j]) {
*cmask |= 1 << i;
break;
}
}
memcpy(oparams->intervals, params->intervals, sizeof(oparams->intervals));
oparams->rmask = __NEW_TO_OLD_MASK(params->rmask);
oparams->cmask = __NEW_TO_OLD_MASK(params->cmask);
oparams->info = params->info;
oparams->msbits = params->msbits;
oparams->rate_num = params->rate_num;
oparams->rate_den = params->rate_den;
oparams->fifo_size = params->fifo_size;
}
static int use_old_hw_params_ioctl(int fd, unsigned int cmd, snd_pcm_hw_params_t *params)
{
struct sndrv_pcm_hw_params_old oparams;
unsigned int cmask = 0;
int res;
snd_pcm_hw_convert_to_old_params(&oparams, params, &cmask);
res = ioctl(fd, cmd, &oparams);
snd_pcm_hw_convert_from_old_params(params, &oparams);
params->cmask |= cmask;
return res;
}
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