PCM: First cut at fast forward by subsampling

This commit is contained in:
Gregory Nutt 2014-07-27 18:33:17 -06:00
parent 0cc9b06eca
commit c9f15ffd3d
2 changed files with 827 additions and 32 deletions

View File

@ -62,10 +62,20 @@
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
#define CONFIG_PCM_DEBUG 1 /* For now */
/* Often defined and re-defined macros */
#ifndef MIN
# define MIN(a,b) (((a) < (b)) ? (a) : (b))
#endif
#ifndef MAX
# define MAX(a,b) (((a) > (b)) ? (a) : (b))
#endif
/****************************************************************************
* Private Types
****************************************************************************/
@ -108,12 +118,20 @@ struct pcm_decode_s
uint8_t align; /* nchannels * bpsamp / 8 */
uint8_t bpsamp; /* Bits per sample: 8 bits = 8, 16 bits = 16 */
uint8_t nchannels; /* Mono=1, Stereo=2 */
bool streaming; /* Streaming PCM data chunk */
/* Set to true once we have parse a valid header and have begun stream
* audio.
*/
#ifndef CONFIG_AUDIO_EXCLUDE_FFORWARD
/* Fast forward support */
bool streaming;
uint8_t subsample; /* Fast forward rate: See AUDIO_SUBSAMPLE_* defns */
uint8_t skip; /* Number of samples to be skipped */
uint8_t npartial; /* Size of the partial sample */
uint8_t partial[4]; /* Holds the partial sample */
struct audio_buf_desc_s bufdesc; /* Allocated buffer description */
FAR struct ap_buffer_s *ffwd; /* Audio buffer being subsampled into */
FAR struct ap_buffer_s *next; /* Next available, empty audio buffer */
FAR struct ap_buffer_s *apb; /* Allocated audio buffer */
#endif
};
/****************************************************************************
@ -138,6 +156,31 @@ static uint16_t pcm_leuint32(uint32_t value);
static inline bool pcm_validwav(FAR const struct wav_header_s *wav);
static bool pcm_parsewav(FAR struct pcm_decode_s *priv, uint8_t *data);
#ifdef CONFIG_AUDIO_MULTI_SESSION
static void pcm_upper_callback(FAR struct pcm_decode_s *priv,
uint16_t reason, FAR struct ap_buffer_s *apb,
uint16_t status, FAR void *session);
#else
static void pcm_upper_callback(FAR struct pcm_decode_s *priv,
uint16_t reason, FAR struct ap_buffer_s *apb,
uint16_t status);
#endif
#ifndef CONFIG_AUDIO_EXCLUDE_FFORWARD
static int pcm_subsample_configure(FAR struct pcm_decode_s *priv,
uint8_t subsample);
#ifdef CONFIG_AUDIO_MULTI_SESSION
static void pcm_subsample_callback(FAR struct pcm_decode_s *priv,
uint16_t reason, FAR struct ap_buffer_s *apb,
uint16_t status, FAR void *session);
#else
static void pcm_subsample_callback(FAR struct pcm_decode_s *priv,
uint16_t reason, FAR struct ap_buffer_s *apb,
uint16_t status);
#endif
static FAR struct ap_buffer_s *pcm_subsample(FAR struct pcm_decode_s *priv,
FAR struct ap_buffer_s *apb);
#endif
/* struct audio_lowerhalf_s methods *****************************************/
@ -368,6 +411,28 @@ static bool pcm_parsewav(FAR struct pcm_decode_s *priv, uint8_t *data)
priv->align = localwav.fmt.align; /* nchannels * bpsamp / 8 */
priv->bpsamp = localwav.fmt.bpsamp; /* Bits per sample: 8 bits = 8, 16 bits = 16 */
priv->nchannels = localwav.fmt.nchannels; /* Mono=1, Stereo=2 */
#ifndef CONFIG_AUDIO_EXCLUDE_FFORWARD
/* We are going to subsample, there then are some restrictions on the
* number of channels and sample sizes that we can handle.
*/
if (priv->bpsamp != 8 && priv->bpsamp != 16)
{
auddbg("ERROR: Cannot support bits per sample of %d in this mode\n",
priv->bpsamp);
return -EINVAL;
}
if (priv->nchannels != 1 && priv->nchannels != 2)
{
auddbg("ERROR: Cannot support number of channles of %d in this mode\n",
priv->nchannels);
return -EINVAL;
}
DEBUGASSERT(priv->align == priv->nchannels * priv->bpsamp / 8);
#endif
}
/* And return true if the the file is a valid WAV header file */
@ -375,6 +440,637 @@ static bool pcm_parsewav(FAR struct pcm_decode_s *priv, uint8_t *data)
return ret;
}
/****************************************************************************
* Name: pcm_upper_callback
*
* Description:
* The lower level driver has just returned a buffer that belongs to the
* uppder level. We need to forward the buffer to the upper level for
* disposition.
*
****************************************************************************/
#ifdef CONFIG_AUDIO_MULTI_SESSION
static void pcm_upper_callback(FAR struct pcm_decode_s *priv,
uint16_t reason, FAR struct ap_buffer_s *apb,
uint16_t status, FAR void *session)
#else
static void pcm_upper_callback(FAR struct pcm_decode_s *priv,
uint16_t reason, FAR struct ap_buffer_s *apb,
uint16_t status)
#endif
{
DEBUGASSERT(priv && apb && priv->export.upper);
/* The buffer belongs to to an upper level. Just forward the event to
* the next level up.
*/
#ifdef CONFIG_AUDIO_MULTI_SESSION
priv->export.upper(priv->export.priv, reason, apb, status, session);
#else
priv->export.upper(priv->export.priv, reason, apb, status);
#endif
}
/****************************************************************************
* Name: pcm_subsample_configure
*
* Description:
* Configure to perform sub-sampling (or not) on the following audio
* buffers.
*
****************************************************************************/
#ifndef CONFIG_AUDIO_EXCLUDE_FFORWARD
static int pcm_subsample_configure(FAR struct pcm_decode_s *priv,
uint8_t subsample)
{
FAR struct audio_lowerhalf_s *lower = priv->lower;
#ifdef CONFIG_AUDIO_DRIVER_SPECIFIC_BUFFERS
struct ap_buffer_info_s bufinfo;
#endif
int ret;
audvdbg("subsample: %d\n", subsample);
/* Three possibilities:
*
* 1. We were playing normally and we have been requested to begin fast
* forwarding.
*/
if (priv->subsample == AUDIO_SUBSAMPLE_NONE)
{
/* There should be no audio buffer allocated in this case */
DEBUGASSERT(priv->ffwd == NULL);
/* Ignore request to stop fast forwarding if we are already
* fast forwarding.
*/
if (subsample != AUDIO_SUBSAMPLE_NONE)
{
/* Check if we already have an audio buffer. This might happen in
* certain race conditions were we exit and return to fast forward
* mode while the audio buffer is in possession of the lower level
* driver.
*/
audvdbg("Start subsampling: apb=%p\n", priv->apb);
if (priv->apb == NULL)
{
#ifdef CONFIG_AUDIO_DRIVER_SPECIFIC_BUFFERS
/* Get the lower level driver's preferred buffer properties */
DEBUGASSERT(lower->ioctl);
ret = lower->ioctl(lower, AUDIOIOC_GETBUFFERINFO,
(unsigned long)&bufinfo))
if (ret < 0)
{
/* Driver doesn't report it's buffer size. Use defaults. */
bufinfo.buffer_size = CONFIG_AUDIO_BUFFER_NUMBYTES;
bufinfo.nbuffers = CONFIG_AUDIO_NUM_BUFFERS;
}
#endif
/* Configure the buffer descriptor */
#ifdef CONFIG_AUDIO_MULTI_SESSION
priv->bufdesc.session = priv->session;
#endif
#ifdef CONFIG_AUDIO_DRIVER_SPECIFIC_BUFFERS
priv->bufdesc.numbytes = bufinfo.buffer_size;
#else
priv->bufdesc.numbytes = CONFIG_AUDIO_BUFFER_NUMBYTES;
#endif
priv->bufdesc.u.ppBuffer = &priv->apb;
/* Perform the allocation */
if (lower->ops->allocbuffer)
{
ret = lower->ops->allocbuffer(lower, &priv->bufdesc);
}
else
{
ret = apb_alloc(&priv->bufdesc);
}
/* Did we get an audio buffer? */
if (ret < 0 || priv->apb == NULL)
{
auddbg("ERROR: Failed to allocate an audio buffer\n");
return -ENOMEM;
}
}
/* Save the current subsample setting. Subsampling will begin on
* then next audio buffer that we receive.
*/
priv->ffwd = priv->apb;
priv->next = NULL;
priv->npartial = 0;
priv->skip = 0;
priv->subsample = subsample;
}
}
/* 2. Were already fast forwarding and we have been asked to change the
* subsampling rate.
*/
else if (subsample != AUDIO_SUBSAMPLE_NONE)
{
/* We should already have an audio buffer allocated in this case */
DEBUGASSERT(priv->apb != NULL && priv->ffwd != NULL);
/* Just save the current subsample setting. It will take effect
* on the next audio buffer that we receive.
*/
priv->subsample = subsample;
}
/* 3. We were already fast forwarding and we have been asked to return to
* normal play.
*/
else if (subsample != AUDIO_SUBSAMPLE_NONE)
{
DEBUGASSERT(priv->apb != NULL && priv->ffwd != NULL);
audvdbg("Stop subsampling\n");
/* Are still holding on to buffers that belong the upper level? */
if (priv->ffwd && priv->ffwd != priv->apb)
{
#ifdef CONFIG_AUDIO_MULTI_SESSION
pcm_upper_callback(priv, AUDIO_CALLBACK_DEQUEUE, priv->ffwd, OK, priv->session);
#else
pcm_upper_callback(priv, AUDIO_CALLBACK_DEQUEUE, priv->ffwd, OK);
#endif
priv->ffwd = NULL;
}
/* We need to free the our working audio buffer. But we also need
* to be careful: The lower level audio driver may have it now.
*
* If the lower level driver has the audio buffer, then we will defer
* freeing it until it is returned to us.
*/
if (priv->ffwd)
{
/* We have it. We can free the audio buffer. NOTE: This audio
* buffer might not be empty, but we will discard it anyway.
* Playing will begin at normal speed at the next, full audio
* buffer.
*/
if (lower->ops->freebuffer)
{
(void)lower->ops->freebuffer(lower, &priv->bufdesc);
}
else
{
apb_free(priv->apb);
}
priv->apb = NULL;
priv->ffwd = NULL;
}
/* And indicate that we are in normal play mode. This will take
* effect when the next audio buffer is received.
*/
priv->next = NULL;
priv->npartial = 0;
priv->skip = 0;
priv->subsample = AUDIO_SUBSAMPLE_NONE;
}
return OK;
}
#endif
/****************************************************************************
* Name: pcm_subsample_callback
*
* Description:
* Our working audio buffer has been returned from the lower level driver.
*
****************************************************************************/
#ifndef CONFIG_AUDIO_EXCLUDE_FFORWARD
#ifdef CONFIG_AUDIO_MULTI_SESSION
static void pcm_subsample_callback(FAR struct pcm_decode_s *priv,
uint16_t reason,
FAR struct ap_buffer_s *apb,
uint16_t status, FAR void *session)
#else
static void pcm_subsample_callback(FAR struct pcm_decode_s *priv,
uint16_t reason,
FAR struct ap_buffer_s *apb,
uint16_t status)
#endif
{
FAR struct audio_lowerhalf_s *lower;
DEBUGASSERT(priv->apb);
audvdbg("apb=%p subsample=%d\n", apb, priv->subsample);
/* Mark the buffer as empty */
apb->nbytes = 0;
apb->curbyte = 0;
/* Possibilities:
* 1. We are no longer streaming and we just need to free the buffer.
* This case happens if we exited fast forward mode while the lower-
* level driver had possession of or working audio buffer.
*/
if (priv->subsample == AUDIO_SUBSAMPLE_NONE)
{
/* Free the working buffer */
lower = priv->lower;
if (lower->ops->freebuffer)
{
(void)lower->ops->freebuffer(lower, &priv->bufdesc);
}
else
{
apb_free(apb);
}
priv->apb = NULL;
}
/* We are still streaming. At any given time, our working audio may be
* (a) the current working buffer, (a) the next working buffer or it, or
* (c) in possession of the lower level driver. None of these are the
* case now since we just got our working audio buffer back from the
*
* 2. We have no fast forward working buffer. Use it buffer as our
* fast forward working buffer. This should never happen.
*/
else if (priv->ffwd == NULL)
{
/* Set the returned buffer as the current working buffer */
priv->ffwd = apb;
}
/* 2. We already have a fast word working buffer, but no next working
* buffer. Save out working audio buffer as the new next buffer.
*/
else
{
/* Set the returned buffer as the next working buffer
*
* REVISIT: This extra buffer is only used on the first buffer. There
* is something wrong:
*
* 1. First buffer: Our private buffer is the working buffer. The
* first audio buffer we receive is compressed into the working
* buffer and the working buffer goes to the lower level. The
* first buffer becomes next working buffer.
* 2. Next buffers: Are compressed into the working buffer, sent
* to the lower level, and become the next working buffer, etc.
* 3. The private buffer eventually comes back here and is saved
* as the "next" buffer, but it is never used again.
*/
DEBUGASSERT(priv->next == NULL);
priv->next = apb;
}
}
#endif
/****************************************************************************
* Name: pcm_subsample
*
* Description:
* Given a newly received audio buffer, perform subsampling into our local
* working audio buffer. Return the subsampled audio buffer to send to
* the lower level driver.
*
****************************************************************************/
#ifndef CONFIG_AUDIO_EXCLUDE_FFORWARD
static FAR struct ap_buffer_s *pcm_subsample(FAR struct pcm_decode_s *priv,
FAR struct ap_buffer_s *apb)
{
FAR struct ap_buffer_s *work;
FAR const uint8_t *src;
FAR uint8_t *dest;
unsigned int destsize;
unsigned int srcsize;
unsigned int skipsize;
unsigned int i;
/* Are we subsampling? */
if (priv->subsample == AUDIO_SUBSAMPLE_NONE)
{
/* No.. do nothing to the buffer */
return apb;
}
/* Yes.. then make sure that we have the required buffers in place */
DEBUGASSERT(priv->ffwd && priv->apb);
/* Yes.. we will need to subsample the newly received buffer. */
work = priv->ffwd;
dest = &work->samp[work->nbytes];
DEBUGASSERT(work->nmaxbytes >= priv->align);
/* This is the number of bytes that we need to skip between samples */
skipsize = priv->align * (priv->subsample - 1);
/* Let's deal with any partial sample data from the last buffer */
if (priv->npartial > 0)
{
/* How much data is available in the new audio buffer */
srcsize = apb->nbytes - apb->curbyte;
/* Let's get an impossible corner case out of the way. What if we
* received a tiny audio buffer. So small, that it (plus any previous
* sample) is smaller than one sample.
*/
if (priv->npartial + srcsize < priv->align)
{
dest = &priv->partial[priv->npartial];
src = &apb->samp[apb->curbyte];
memcpy(dest, src, srcsize);
priv->npartial += srcsize;
apb->curbyte += srcsize;
goto exit_apb_empty;
}
/* No, we do at least have enough to complete the partial sample */
/* Copy the first part of the partial sample that was saved from
* the last buffer.
*/
src = priv->partial;
for (i = 0; i < priv->npartial; i++)
{
*dest++ = *src++;
}
priv->npartial = 0;
/* Now copy data from new audio buffer to complete the sample */
src = &apb->samp[apb->curbyte];
for (i = 0; i < priv->align; i++)
{
*dest++ = *src++;
apb->curbyte++;
}
/* Update the number of bytes in the working buffer and reset the skip
* value
*/
work->nbytes += skipsize;
priv->skip = skipsize;
}
/* Now loop until either (1) the working audio buffer is full, or (2)
* the newly received audio buffer is empty.
*/
src = &apb->samp[apb->curbyte];
srcsize = apb->nbytes - apb->curbyte;
destsize = work->nmaxbytes - work->nbytes;
while (srcsize > 0 && destsize > 0)
{
/* Do we need to skip ahead in the buffer? */
if (priv->skip > 0)
{
/* How much can we skip in this buffer? Depends on the smaller
* of (1) the number of bytes that we need to skip and (2) the
* number of bytes available in the newly received audio buffer.
*/
unsigned int discard = MIN(priv->skip, srcsize);
priv->skip -= discard;
apb->curbyte += discard;
srcsize -= discard;
/* Did we skip to the end of the audio buffer? */
if (srcsize <= 0)
{
goto exit_apb_empty;
}
}
/* We have skipped over the required number of bytes and we are ready
* to take the next sample. Is there space for a whole sample in the
* buffer?
*/
else if (srcsize < priv->align)
{
/* No.. copy the partial sample to the partial sample buffer */
dest = priv->partial;
for (i = 0; i < srcsize; i++)
{
*dest++ = *src++;
}
priv->npartial = srcsize;
apb->curbyte += srcsize;
/* We are finished with this audio buffer. On the next buffer,
* the fact that skip == 0 and that priv->npartial > 0 will kick
* off the re-synchronization logic at the beginning of this
* function.
*/
goto exit_apb_empty;
}
/* Plenty of space! Copy the sample from the audio buffer into the
* working buffer.
*/
else
{
/* Now copy the sample from new audio buffer to working buffer */
for (i = 0; i < priv->align; i++)
{
*dest++ = *src++;
}
/* Update indices and sizes and reset the skip value */
apb->curbyte += priv->align;
srcsize -= priv->align;
work->nbytes += priv->align;
destsize -= priv->align;
priv->skip = skipsize;
}
}
/* We get here in one of two cases. Either (1) the source audio buffer
* became empty, and/or (2) the working audio buffer became which. Which
* is the case?
*
* REVISIT: Should there be a threshold here so that we do not send
* really tiny buffers to the
*/
if (srcsize > 0)
{
/* How could the working buffer be empty in this case? */
DEBUGASSERT(work->nbytes > 0);
/* This seems overly complex. We either need another buffer or else
* we have to do this: Sub-ample in place.
*/
dest = apb->samp;
destsize = apb->nmaxbytes;
while (srcsize > 0)
{
/* Do we need to skip ahead in the buffer? */
if (priv->skip > 0)
{
/* How much can we skip in this buffer? Depends on the
* smaller of (1) the number of bytes that we need to skip
* and (2) the number of bytes available in the audio buffer.
*/
unsigned int discard = MIN(priv->skip, srcsize);
priv->skip -= discard;
srcsize -= discard;
/* Did we skip to the end of the audio buffer? */
if (srcsize <= 0)
{
break;
}
}
/* We have skipped over the required number of bytes and we are
* ready to take the next sample. Is there space for a whole
* sample in the buffer?
*/
else if (srcsize < priv->align)
{
/* No.. copy the partial sample to the partial sample buffer */
dest = priv->partial;
for (i = 0; i < srcsize; i++)
{
*dest++ = *src++;
}
priv->npartial = srcsize;
break;
}
/* Plenty of space! Copy the sample from the end of the audio
* buffer to the beginning.
*/
else
{
/* Now copy the sample from new audio buffer to working buffer */
for (i = 0; i < priv->align; i++)
{
*dest++ = *src++;
}
/* Update indices and sizes and reset the skip value */
srcsize -= priv->align;
destsize -= priv->align;
priv->skip = skipsize;
}
}
/* Set the buffer that we just emptied as the new working buffer */
apb->curbyte = 0;
apb->nbytes = apb->nmaxbytes - destsize;
priv->ffwd = apb;
/* Return the working buffer */
return work;
}
exit_apb_empty:
/* We get here in the case that the source audio buffer is empty. The
* working buffer may be empty or non-empty.
*/
/* Is there anything in the working buffer?
*
* REVISIT: Should there be a threshold here so that we do not send
* really tiny buffers to the
*/
if (work->nbytes > 0)
{
/* Set the buffer that we just emptied as the new working buffer */
apb->curbyte = 0;
apb->nbytes = 0;
priv->ffwd = apb;
/* Return the working buffer */
return work;
}
/* We don't have any data to forward to the lower level driver */
return NULL;
}
#endif
/****************************************************************************
* Name: pcm_getcaps
*
@ -447,10 +1143,38 @@ static int pcm_configure(FAR struct audio_lowerhalf_s *dev,
{
FAR struct pcm_decode_s *priv = (FAR struct pcm_decode_s *)dev;
FAR struct audio_lowerhalf_s *lower;
#ifndef CONFIG_AUDIO_EXCLUDE_FFORWARD
int ret;
#endif
DEBUGASSERT(priv);
/* Defer the operation to the lower device driver */
#ifndef CONFIG_AUDIO_EXCLUDE_FFORWARD
/* Pick off commands to perform sub-sampling. Those are done by this
* decoder. All of configuration settings are handled by the lower level
* audio driver.
*/
if (caps->ac_type == AUDIO_TYPE_PROCESSING &&
caps->ac_format.hw == AUDIO_PU_SUBSAMPLE_FORWARD)
{
/* Configure subsampling */
ret = pcm_subsample_configure(priv, caps->ac_controls.b[0]);
if (ret < 0)
{
auddbg("ERROR: pcm_subsample_configure failed: %d\n", ret);
}
/* Return to avoid forwarding the configuration to the lower level
* driver.
*/
return ret;
}
#endif
/* Defer all other operations to the lower device driver */
lower = priv->lower;
DEBUGASSERT(lower && lower->ops->configure);
@ -724,13 +1448,26 @@ static int pcm_enqueuebuffer(FAR struct audio_lowerhalf_s *dev,
if (priv->streaming)
{
/* Yes, just give the buffer to the lower driver */
/* Yes, we are streaming */
#ifndef CONFIG_AUDIO_EXCLUDE_FFORWARD
audvdbg("Received: apb=%p curbyte=%d nbytes=%d\n",
apb, apb->curbyte, apb->nbytes);
/* Perform any necessary subsampling operations */
apb = pcm_subsample(priv, apb);
if (apb)
#endif
{
/* Then give the audio buffer to the lower driver */
audvdbg("Pass to lower enqueuebuffer: apb=%p curbyte=%d nbytes=%d\n",
apb, apb->curbyte, apb->nbytes);
return lower->ops->enqueuebuffer(lower, apb);
}
}
/* No.. then this must be the first buffer that we have seen (since we
* will error out out if the first buffer is smaller than the WAV file
@ -778,15 +1515,29 @@ static int pcm_enqueuebuffer(FAR struct audio_lowerhalf_s *dev,
return ret;
}
/* Bump up the data offset and pass the buffer to the lower level */
/* Bump up the data offset */
apb->curbyte += sizeof(struct wav_header_s);
#ifndef CONFIG_AUDIO_EXCLUDE_FFORWARD
audvdbg("Begin streaming: apb=%p curbyte=%d nbytes=%d\n",
apb, apb->curbyte, apb->nbytes);
/* Perform any necessary subsampling operations */
apb = pcm_subsample(priv, apb);
if (apb)
#endif
{
/* Then give the audio buffer to the lower driver */
audvdbg("Pass to lower enqueuebuffer: apb=%p curbyte=%d nbytes=%d\n",
apb, apb->curbyte, apb->nbytes);
return lower->ops->enqueuebuffer(lower, apb);
}
}
}
/* This is not a WAV file! */
@ -952,24 +1703,59 @@ static int pcm_release(FAR struct audio_lowerhalf_s *dev)
/* Audio callback */
#ifdef CONFIG_AUDIO_MULTI_SESSION
static void pcm_callback(FAR void *arg, uint16_t reason,
FAR struct ap_buffer_s *apb, uint16_t status,
FAR void *session)
#else
{
FAR struct pcm_decode_s *priv = (FAR struct pcm_decode_s *)arg;
#ifndef CONFIG_AUDIO_EXCLUDE_FFORWARD
/* If this is our internal working audio buffer that we use for subsampling,
* then we are the owner of the buffer and we don't want to return it to
* the upper level.
*/
if (priv->apb == apb)
{
pcm_subsample_callback(priv, reason, apb, status, session);
}
else
#endif
{
/* Return the buffer to the upper level */
pcm_upper_callback(priv, reason, apb, status, session);
}
}
#else /* CONFIG_AUDIO_MULTI_SESSION */
static void pcm_callback(FAR void *arg, uint16_t reason,
FAR struct ap_buffer_s *apb, uint16_t status)
{
FAR struct pcm_decode_s *priv = (FAR struct pcm_decode_s *)arg;
/* Just forward the event to our upper half (I know, too many halves) */
#ifndef CONFIG_AUDIO_EXCLUDE_FFORWARD
/* If this is our internal working audio buffer that we use for subsampling,
* then we are the owner of the buffer and we don't want to return it to
* the upper level.
*/
#ifdef CONFIG_AUDIO_MULTI_SESSION
priv->export.upper(priv->export.priv, reason, apb, status, session);
#else
priv->export.upper(priv->export.priv, reason, apb, status);
if (priv->apb == apb)
{
pcm_subsample_callback(priv, reason, apb, status);
}
else
#endif
{
/* Return the buffer to the upper level */
pcm_upper_callback(priv, reason, apb, status);
}
}
#endif
#endif /* CONFIG_AUDIO_MULTI_SESSION */
/****************************************************************************
* Public Functions

View File

@ -649,18 +649,27 @@ static int null_resume(FAR struct audio_lowerhalf_s *dev)
static int null_enqueuebuffer(FAR struct audio_lowerhalf_s *dev,
FAR struct ap_buffer_s *apb)
{
/* Take a reference */
FAR struct null_dev_s *priv = (FAR struct null_dev_s *)dev;
apb_reference(apb);
audvdbg("apb=%p curbyte=%d nbytes=%d\n", apb, apb->curbyte, apb->nbytes);
/* say that we consumed all of the data */
/* Say that we consumed all of the data */
apb->curbyte = apb->nbytes;
/* Release the reference and return success */
/* And return the buffer to the upper level */
apb_free(apb);
DEBUGASSERT(priv && apb && priv->dev.upper);
/* The buffer belongs to to an upper level. Just forward the event to
* the next level up.
*/
#ifdef CONFIG_AUDIO_MULTI_SESSION
priv->dev.upper(priv->dev.priv, AUDIO_CALLBACK_DEQUEUE, apb, OK, NULL);
#else
priv->dev.upper(priv->dev.priv, AUDIO_CALLBACK_DEQUEUE, apb, OK);
#endif
audvdbg("Return OK\n");
return OK;