/**
* \file pcm/pcm_mmap_emul.c
* \ingroup PCM_Plugins
* \brief PCM Mmap-Emulation Plugin Interface
* \author Takashi Iwai <tiwai@suse.de>
* \date 2007
*/
/*
* PCM - Mmap-Emulation
* Copyright (c) 2007 by 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
*
*/
#include "pcm_local.h"
#include "pcm_generic.h"
#ifndef PIC
/* entry for static linking */
const char *_snd_module_pcm_mmap_emul = "";
#endif
#ifndef DOC_HIDDEN
/*
*
*/
typedef struct {
snd_pcm_generic_t gen;
unsigned int mmap_emul :1;
snd_pcm_uframes_t hw_ptr;
snd_pcm_uframes_t appl_ptr;
snd_pcm_uframes_t start_threshold;
} mmap_emul_t;
#endif
/*
* here goes a really tricky part; hw_refine falls back to ACCESS_RW_* type
* when ACCESS_MMAP_* isn't supported by the hardware.
*/
static int snd_pcm_mmap_emul_hw_refine(snd_pcm_t *pcm,
snd_pcm_hw_params_t *params)
{
mmap_emul_t *map = pcm->private_data;
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_none(&mask);
err = snd_pcm_hw_refine(map->gen.slave, params);
if (err < 0) {
snd_pcm_hw_params_t new = *params;
/* try to use RW_* */
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;
err = snd_pcm_hw_refine(map->gen.slave, &new);
if (err < 0)
return err;
*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);
params->cmask |= 1<<SND_PCM_HW_PARAM_ACCESS;
}
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);
params->cmask |= 1<<SND_PCM_HW_PARAM_ACCESS;
}
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);
params->cmask |= 1<<SND_PCM_HW_PARAM_ACCESS;
}
}
}
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);
params->cmask |= 1<<SND_PCM_HW_PARAM_ACCESS;
}
}
}
return 0;
}
/*
* hw_params needs a similar hack like hw_refine, but it's much simpler
* because now snd_pcm_hw_params_t takes only one choice for each item.
*
* Here, when the normal hw_params call fails, it turns on the mmap_emul
* flag and tries to use ACCESS_RW_* mode.
*
* In mmap_emul mode, the appl_ptr and hw_ptr are handled individually
* from the layering slave PCM, and they are sync'ed appropriately in
* each read/write or avail_update/commit call.
*/
static int snd_pcm_mmap_emul_hw_params(snd_pcm_t *pcm,
snd_pcm_hw_params_t *params)
{
mmap_emul_t *map = pcm->private_data;
snd_pcm_hw_params_t old = *params;
snd_pcm_access_t access;
snd_pcm_access_mask_t oldmask;
snd_pcm_access_mask_t *pmask;
int err;
err = _snd_pcm_hw_params_internal(map->gen.slave, params);
if (err >= 0) {
map->mmap_emul = 0;
return err;
}
*params = old;
pmask = (snd_pcm_access_mask_t *)snd_pcm_hw_param_get_mask(params, SND_PCM_HW_PARAM_ACCESS);
oldmask = *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(pmask,
SND_PCM_ACCESS_MMAP_INTERLEAVED);
snd_pcm_access_mask_set(pmask, SND_PCM_ACCESS_RW_INTERLEAVED);
break;
case SND_PCM_ACCESS_MMAP_NONINTERLEAVED:
snd_pcm_access_mask_reset(pmask,
SND_PCM_ACCESS_MMAP_NONINTERLEAVED);
snd_pcm_access_mask_set(pmask,
SND_PCM_ACCESS_RW_NONINTERLEAVED);
break;
default:
goto _err;
}
err = _snd_pcm_hw_params_internal(map->gen.slave, params);
if (err < 0)
goto _err;
/* need to back the access type to relieve apps */
*pmask = oldmask;
/* OK, we do fake */
map->mmap_emul = 1;
map->appl_ptr = 0;
map->hw_ptr = 0;
snd_pcm_set_hw_ptr(pcm, &map->hw_ptr, -1, 0);
snd_pcm_set_appl_ptr(pcm, &map->appl_ptr, -1, 0);
return 0;
_err:
err = -errno;
return err;
}
static int snd_pcm_mmap_emul_sw_params(snd_pcm_t *pcm,
snd_pcm_sw_params_t *params)
{
mmap_emul_t *map = pcm->private_data;
int err;
if (!map->mmap_emul)
return snd_pcm_generic_sw_params(pcm, params);
map->start_threshold = params->start_threshold;
/* HACK: don't auto-start in the slave PCM */
params->start_threshold = pcm->boundary;
err = snd_pcm_generic_sw_params(pcm, params);
if (err < 0)
return err;
/* restore the value for this PCM */
params->start_threshold = map->start_threshold;
return err;
}
static int snd_pcm_mmap_emul_prepare(snd_pcm_t *pcm)
{
mmap_emul_t *map = pcm->private_data;
int err;
err = snd_pcm_generic_prepare(pcm);
if (err < 0)
return err;
map->hw_ptr = map->appl_ptr = 0;
return err;
}
static int snd_pcm_mmap_emul_reset(snd_pcm_t *pcm)
{
mmap_emul_t *map = pcm->private_data;
int err;
err = snd_pcm_generic_reset(pcm);
if (err < 0)
return err;
map->hw_ptr = map->appl_ptr = 0;
return err;
}
static snd_pcm_sframes_t
snd_pcm_mmap_emul_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
{
frames = snd_pcm_generic_rewind(pcm, frames);
if (frames > 0)
snd_pcm_mmap_appl_backward(pcm, frames);
return frames;
}
static snd_pcm_sframes_t
snd_pcm_mmap_emul_forward(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
{
frames = snd_pcm_generic_forward(pcm, frames);
if (frames > 0)
snd_pcm_mmap_appl_forward(pcm, frames);
return frames;
}
/* write out the uncommitted chunk on mmap buffer to the slave PCM */
static snd_pcm_sframes_t
sync_slave_write(snd_pcm_t *pcm)
{
mmap_emul_t *map = pcm->private_data;
snd_pcm_t *slave = map->gen.slave;
snd_pcm_uframes_t offset;
snd_pcm_sframes_t size;
/* HACK: don't start stream automatically at commit in mmap mode */
pcm->start_threshold = pcm->boundary;
size = map->appl_ptr - *slave->appl.ptr;
if (size < 0)
size += pcm->boundary;
if (size) {
offset = *slave->appl.ptr % pcm->buffer_size;
size = snd_pcm_write_mmap(pcm, offset, size);
}
pcm->start_threshold = map->start_threshold; /* restore */
return size;
}
/* read the available chunk on the slave PCM to mmap buffer */
static snd_pcm_sframes_t
sync_slave_read(snd_pcm_t *pcm)
{
mmap_emul_t *map = pcm->private_data;
snd_pcm_t *slave = map->gen.slave;
snd_pcm_uframes_t offset;
snd_pcm_sframes_t size;
size = *slave->hw.ptr - map->hw_ptr;
if (size < 0)
size += pcm->boundary;
if (!size)
return 0;
offset = map->hw_ptr % pcm->buffer_size;
size = snd_pcm_read_mmap(pcm, offset, size);
if (size > 0)
snd_pcm_mmap_hw_forward(pcm, size);
return 0;
}
static snd_pcm_sframes_t
snd_pcm_mmap_emul_mmap_commit(snd_pcm_t *pcm, snd_pcm_uframes_t offset,
snd_pcm_uframes_t size)
{
mmap_emul_t *map = pcm->private_data;
snd_pcm_t *slave = map->gen.slave;
snd_pcm_mmap_appl_forward(pcm, size);
if (!map->mmap_emul)
return snd_pcm_mmap_commit(slave, offset, size);
if (pcm->stream == SND_PCM_STREAM_PLAYBACK)
sync_slave_write(pcm);
return size;
}
static snd_pcm_sframes_t snd_pcm_mmap_emul_avail_update(snd_pcm_t *pcm)
{
mmap_emul_t *map = pcm->private_data;
snd_pcm_t *slave = map->gen.slave;
if (!map->mmap_emul || pcm->stream == SND_PCM_STREAM_PLAYBACK)
map->hw_ptr = *slave->hw.ptr;
else
sync_slave_read(pcm);
return snd_pcm_mmap_avail(pcm);
}
static void snd_pcm_mmap_emul_dump(snd_pcm_t *pcm, snd_output_t *out)
{
mmap_emul_t *map = pcm->private_data;
snd_output_printf(out, "Mmap emulation PCM\n");
if (pcm->setup) {
snd_output_printf(out, "Its setup is:\n");
snd_pcm_dump_setup(pcm, out);
}
snd_output_printf(out, "Slave: ");
snd_pcm_dump(map->gen.slave, out);
}
static const snd_pcm_ops_t snd_pcm_mmap_emul_ops = {
.close = snd_pcm_generic_close,
.info = snd_pcm_generic_info,
.hw_refine = snd_pcm_mmap_emul_hw_refine,
.hw_params = snd_pcm_mmap_emul_hw_params,
.hw_free = snd_pcm_generic_hw_free,
.sw_params = snd_pcm_mmap_emul_sw_params,
.channel_info = snd_pcm_generic_channel_info,
.dump = snd_pcm_mmap_emul_dump,
.nonblock = snd_pcm_generic_nonblock,
.async = snd_pcm_generic_async,
.mmap = snd_pcm_generic_mmap,
.munmap = snd_pcm_generic_munmap,
.query_chmaps = snd_pcm_generic_query_chmaps,
.get_chmap = snd_pcm_generic_get_chmap,
.set_chmap = snd_pcm_generic_set_chmap,
};
static const snd_pcm_fast_ops_t snd_pcm_mmap_emul_fast_ops = {
.status = snd_pcm_generic_status,
.state = snd_pcm_generic_state,
.hwsync = snd_pcm_generic_hwsync,
.delay = snd_pcm_generic_delay,
.prepare = snd_pcm_mmap_emul_prepare,
.reset = snd_pcm_mmap_emul_reset,
.start = snd_pcm_generic_start,
.drop = snd_pcm_generic_drop,
.drain = snd_pcm_generic_drain,
.pause = snd_pcm_generic_pause,
.rewindable = snd_pcm_generic_rewindable,
.rewind = snd_pcm_mmap_emul_rewind,
.forwardable = snd_pcm_generic_forwardable,
.forward = snd_pcm_mmap_emul_forward,
.resume = snd_pcm_generic_resume,
.link = snd_pcm_generic_link,
.link_slaves = snd_pcm_generic_link_slaves,
.unlink = snd_pcm_generic_unlink,
.writei = snd_pcm_generic_writei,
.writen = snd_pcm_generic_writen,
.readi = snd_pcm_generic_readi,
.readn = snd_pcm_generic_readn,
.avail_update = snd_pcm_mmap_emul_avail_update,
.mmap_commit = snd_pcm_mmap_emul_mmap_commit,
.htimestamp = snd_pcm_generic_htimestamp,
.poll_descriptors = snd_pcm_generic_poll_descriptors,
.poll_descriptors_count = snd_pcm_generic_poll_descriptors_count,
.poll_revents = snd_pcm_generic_poll_revents,
.may_wait_for_avail_min = snd_pcm_generic_may_wait_for_avail_min,
};
#ifndef DOC_HIDDEN
int __snd_pcm_mmap_emul_open(snd_pcm_t **pcmp, const char *name,
snd_pcm_t *slave, int close_slave)
{
snd_pcm_t *pcm;
mmap_emul_t *map;
int err;
map = calloc(1, sizeof(*map));
if (!map)
return -ENOMEM;
map->gen.slave = slave;
map->gen.close_slave = close_slave;
err = snd_pcm_new(&pcm, SND_PCM_TYPE_MMAP_EMUL, name,
slave->stream, slave->mode);
if (err < 0) {
free(map);
return err;
}
pcm->ops = &snd_pcm_mmap_emul_ops;
pcm->fast_ops = &snd_pcm_mmap_emul_fast_ops;
pcm->private_data = map;
pcm->poll_fd = slave->poll_fd;
pcm->poll_events = slave->poll_events;
pcm->tstamp_type = slave->tstamp_type;
snd_pcm_set_hw_ptr(pcm, &map->hw_ptr, -1, 0);
snd_pcm_set_appl_ptr(pcm, &map->appl_ptr, -1, 0);
*pcmp = pcm;
return 0;
}
#endif
/*! \page pcm_plugins
\section pcm_plugins_mmap_emul Plugin: mmap_emul
\code
pcm.name {
type mmap_emul
slave PCM
}
\endcode
\subsection pcm_plugins_mmap_emul_funcref Function reference
<UL>
<LI>_snd_pcm_hw_open()
</UL>
*/
/**
* \brief Creates a new mmap_emul 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_mmap_emul_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;
int err;
snd_pcm_t *spcm;
snd_config_t *slave = NULL, *sconf;
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, "slave") == 0) {
slave = n;
continue;
}
SNDERR("Unknown field %s", id);
return -EINVAL;
}
if (!slave) {
SNDERR("slave is not defined");
return -EINVAL;
}
err = snd_pcm_slave_conf(root, slave, &sconf, 0);
if (err < 0)
return err;
err = snd_pcm_open_slave(&spcm, root, sconf, stream, mode, conf);
snd_config_delete(sconf);
if (err < 0)
return err;
err = __snd_pcm_mmap_emul_open(pcmp, name, spcm, 1);
if (err < 0)
snd_pcm_close(spcm);
return err;
}
#ifndef DOC_HIDDEN
SND_DLSYM_BUILD_VERSION(_snd_pcm_mmap_emul_open, SND_PCM_DLSYM_VERSION);
#endif