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I2S simplifed audio buffer queuing

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This commit is contained in:
Gregory Nutt 2013-11-10 14:51:33 -06:00
parent 9f10539750
commit 64a7e96f1f
4 changed files with 116 additions and 163 deletions
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4
ChangeLog
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@ -6027,4 +6027,6 @@
NuttX Kernel build (2013-11-10).
* arch/arm/src/sama5/sam_ssc.c and Kconfig: Add configurable support
for SSC loopback mode (2013-11-10).
* include/nuttx/audio/i2s.h, arch/arm/src/sama5/sam_ssc.c, and
drivers/audio/i2schar.c: Improvied I2S interface design: Simplified
audio buffer queuing (2013-11-10).

123
arch/arm/src/sama5/sam_ssc.c
View File

@ -242,11 +242,10 @@
struct sam_buffer_s
{
struct sam_buffer_s *flink; /* Supports a singly linked list */
void *callback; /* Function to call when the transfer completes */
i2s_callback_t callback; /* Function to call when the transfer completes */
uint32_t timeout; /* The timeout value to use with DMA transfers */
void *arg; /* The argument to be returned with the callback */
void *buffer; /* I/O buffer */
size_t nbytes; /* Number of valid bytes in the buffer */
struct ap_buffer_s *apb; /* The audio buffer */
int result; /* The result of the transfer */
};
@ -399,13 +398,12 @@ static void ssc_txdma_callback(DMA_HANDLE handle, void *arg, int result);
static uint32_t ssc_rxsamplerate(struct i2s_dev_s *dev, uint32_t rate);
static uint32_t ssc_rxdatawidth(struct i2s_dev_s *dev, int bits);
static int ssc_receive(struct i2s_dev_s *dev, void *buffer,
size_t nbytes, i2s_rxcallback_t callback, void *arg,
uint32_t timeout);
static int ssc_receive(struct i2s_dev_s *dev, struct ap_buffer_s *apb,
i2s_callback_t callback, void *arg, uint32_t timeout);
static uint32_t ssc_txsamplerate(struct i2s_dev_s *dev, uint32_t rate);
static uint32_t ssc_txdatawidth(struct i2s_dev_s *dev, int bits);
static int ssc_send(struct i2s_dev_s *dev, const void *buffer,
size_t nbytes, i2s_txcallback_t callback, void *arg,
static int ssc_send(struct i2s_dev_s *dev, struct ap_buffer_s *apb,
i2s_callback_t callback, void *arg,
uint32_t timeout);
/* Initialization */
@ -1013,6 +1011,7 @@ static void ssc_rxdma_timeout(int argc, uint32_t arg)
static int ssc_rxdma_setup(struct sam_ssc_s *priv)
{
struct sam_buffer_s *bfcontainer;
struct ap_buffer_s *apb;
uintptr_t paddr;
uintptr_t maddr;
uint32_t timeout;
@ -1049,17 +1048,21 @@ static int ssc_rxdma_setup(struct sam_ssc_s *priv)
/* Remove the pending RX transfer at the head of the RX pending queue. */
bfcontainer = (struct sam_buffer_s *)sq_remfirst(&priv->rxpend);
DEBUGASSERT(bfcontainer && bfcontainer->apb);
apb = bfcontainer->apb;
DEBUGASSERT(((uintptr_t)apb->samp & 3) == 0);
/* Physical address of the SSC RHR register and of the buffer location
* in RAM.
*/
paddr = ssc_physregaddr(priv, SAM_SSC_RHR_OFFSET);
maddr = sam_physramaddr((uintptr_t)bfcontainer->buffer);
maddr = sam_physramaddr((uintptr_t)apb->samp);
/* Configure the RX DMA */
sam_dmarxsetup(priv->rxdma, paddr, maddr, bfcontainer->nbytes);
sam_dmarxsetup(priv->rxdma, paddr, maddr, apb->nmaxbytes);
/* Increment the DMA timeout */
@ -1075,6 +1078,14 @@ static int ssc_rxdma_setup(struct sam_ssc_s *priv)
/* Add the container to the list of active DMAs */
sq_addlast((sq_entry_t *)bfcontainer, &priv->rxact);
/* Invalidate the data cache so that nothing gets flush into the
* DMA buffer after starting the DMA transfer.
*/
cp15_invalidate_dcache((uintptr_t)apb->samp,
(uintptr_t)apb->samp + apb->nmaxbytes);
}
while (!sq_empty(&priv->rxpend));
@ -1082,13 +1093,6 @@ static int ssc_rxdma_setup(struct sam_ssc_s *priv)
ssc_rxdma_sample(priv, DMA_AFTER_SETUP);
/* Invalidate the data cache so that nothing gets flush into the
* DMA buffer after starting the DMA transfer.
*/
cp15_invalidate_dcache((uintptr_t)bfcontainer->buffer,
(uintptr_t)bfcontainer->buffer + bfcontainer->nbytes);
/* Start the DMA, saving the container as the current active transfer */
sam_dmastart(priv->rxdma, ssc_rxdma_callback, priv);
@ -1140,7 +1144,6 @@ static void ssc_rx_worker(void *arg)
{
struct sam_ssc_s *priv = (struct sam_ssc_s *)arg;
struct sam_buffer_s *bfcontainer;
i2s_rxcallback_t callback;
irqstate_t flags;
DEBUGASSERT(priv);
@ -1203,10 +1206,12 @@ static void ssc_rx_worker(void *arg)
/* Perform the TX transfer done callback */
DEBUGASSERT(bfcontainer && bfcontainer->callback);
bfcontainer->callback(&priv->dev, bfcontainer->apb,
bfcontainer->arg, bfcontainer->result);
callback = (i2s_rxcallback_t)bfcontainer->callback;
callback(&priv->dev, bfcontainer->buffer, bfcontainer->nbytes,
bfcontainer->arg, bfcontainer->result);
/* Release our reference on the audio buffer */
apb_free(bfcontainer->apb);
/* And release the buffer container */
@ -1381,6 +1386,7 @@ static void ssc_txdma_timeout(int argc, uint32_t arg)
static int ssc_txdma_setup(struct sam_ssc_s *priv)
{
struct sam_buffer_s *bfcontainer;
struct ap_buffer_s *apb;
uintptr_t paddr;
uintptr_t maddr;
uint32_t timeout;
@ -1417,6 +1423,10 @@ static int ssc_txdma_setup(struct sam_ssc_s *priv)
/* Remove the pending TX transfer at the head of the TX pending queue. */
bfcontainer = (struct sam_buffer_s *)sq_remfirst(&priv->txpend);
DEBUGASSERT(bfcontainer && bfcontainer->apb);
apb = bfcontainer->apb;
DEBUGASSERT(((uintptr_t)apb->samp & 3) == 0);
/* Physical address of the SSC THR register and of the buffer location
* in
@ -1424,11 +1434,11 @@ static int ssc_txdma_setup(struct sam_ssc_s *priv)
*/
paddr = ssc_physregaddr(priv, SAM_SSC_THR_OFFSET);
maddr = sam_physramaddr((uintptr_t)bfcontainer->buffer);
maddr = sam_physramaddr((uintptr_t)apb->samp);
/* Configure the TX DMA */
sam_dmatxsetup(priv->txdma, paddr, maddr, bfcontainer->nbytes);
sam_dmatxsetup(priv->txdma, paddr, maddr, apb->nbytes);
/* Increment the DMA timeout */
@ -1444,6 +1454,14 @@ static int ssc_txdma_setup(struct sam_ssc_s *priv)
/* Add the container to the list of active DMAs */
sq_addlast((sq_entry_t *)bfcontainer, &priv->txact);
/* Flush the data cache so that everything is in the physical memory
* before starting the DMA.
*/
cp15_clean_dcache((uintptr_t)apb->samp,
(uintptr_t)apb->samp + apb->nbytes);
}
while (!sq_empty(&priv->txpend));
@ -1451,13 +1469,6 @@ static int ssc_txdma_setup(struct sam_ssc_s *priv)
ssc_txdma_sample(priv, DMA_AFTER_SETUP);
/* Flush the data cache so that everything is in the physical memory
* before starting the DMA.
*/
cp15_clean_dcache((uintptr_t)bfcontainer->buffer,
(uintptr_t)bfcontainer->buffer + bfcontainer->nbytes);
/* Start the DMA, saving the container as the current active transfer */
sam_dmastart(priv->txdma, ssc_txdma_callback, priv);
@ -1509,7 +1520,6 @@ static void ssc_tx_worker(void *arg)
{
struct sam_ssc_s *priv = (struct sam_ssc_s *)arg;
struct sam_buffer_s *bfcontainer;
i2s_txcallback_t callback;
irqstate_t flags;
DEBUGASSERT(priv);
@ -1572,10 +1582,12 @@ static void ssc_tx_worker(void *arg)
/* Perform the TX transfer done callback */
DEBUGASSERT(bfcontainer && bfcontainer->callback);
bfcontainer->callback(&priv->dev, bfcontainer->apb,
bfcontainer->arg, bfcontainer->result);
callback = (i2s_txcallback_t)bfcontainer->callback;
callback(&priv->dev, bfcontainer->buffer, bfcontainer->nbytes,
bfcontainer->arg, bfcontainer->result);
/* Release our reference on the audio buffer */
apb_free(bfcontainer->apb);
/* And release the buffer container */
@ -1780,9 +1792,7 @@ static uint32_t ssc_rxdatawidth(struct i2s_dev_s *dev, int bits)
*
* Input Parameters:
* dev - Device-specific state data
* buffer - A pointer to the buffer in which to recieve data
* nbytes - The length of data that can be received in the buffer in number
* of bytes.
* apb - A pointer to the audio buffer in which to recieve data
* callback - A user provided callback function that will be called at
* the completion of the transfer. The callback will be
* performed in the context of the worker thread.
@ -1804,18 +1814,17 @@ static uint32_t ssc_rxdatawidth(struct i2s_dev_s *dev, int bits)
*
****************************************************************************/
static int ssc_receive(struct i2s_dev_s *dev, void *buffer,
size_t nbytes, i2s_rxcallback_t callback,
void *arg, uint32_t timeout)
static int ssc_receive(struct i2s_dev_s *dev, struct ap_buffer_s *apb,
i2s_callback_t callback, void *arg, uint32_t timeout)
{
struct sam_ssc_s *priv = (struct sam_ssc_s *)dev;
struct sam_buffer_s *bfcontainer;
irqstate_t flags;
int ret;
i2svdbg("buffer=%p nbytes=%d\n", buffer, (int)nbytes);
DEBUGASSERT(priv && buffer && ((uintptr_t)buffer & 3) == 0);
DEBUGASSERT(priv && apb && ((uintptr_t)apb->samp & 3) == 0);
i2svdbg("apb=%p nmaxbytes=%d\n", apb, apb->nmaxbytes);
#ifdef SSC_HAVE_RX
/* Allocate a buffer container in advance */
@ -1835,13 +1844,16 @@ static int ssc_receive(struct i2s_dev_s *dev, void *buffer,
goto errout_with_exclsem;
}
/* Add a reference to the audio buffer */
apb_reference(apb);
/* Initialize the buffer container structure */
bfcontainer->callback = (void *)callback;
bfcontainer->timeout = timeout;
bfcontainer->arg = arg;
bfcontainer->buffer = buffer;
bfcontainer->nbytes = nbytes;
bfcontainer->apb = apb;
bfcontainer->result = -EBUSY;
/* Add the buffer container to the end of the RX pending queue */
@ -1957,9 +1969,8 @@ static uint32_t ssc_txdatawidth(struct i2s_dev_s *dev, int bits)
* Send a block of data on I2S.
*
* Input Parameters:
* dev - Device-specific state data
* buffer - A pointer to the buffer of data to be sent
* nbytes - the length of data to send from the buffer in number of bytes.
* dev - Device-specific state data
* apb - A pointer to the audio buffer from which to send data
* callback - A user provided callback function that will be called at
* the completion of the transfer. The callback will be
* performed in the context of the worker thread.
@ -1981,17 +1992,16 @@ static uint32_t ssc_txdatawidth(struct i2s_dev_s *dev, int bits)
*
****************************************************************************/
static int ssc_send(struct i2s_dev_s *dev, const void *buffer,
size_t nbytes, i2s_txcallback_t callback,
void *arg, uint32_t timeout)
static int ssc_send(struct i2s_dev_s *dev, struct ap_buffer_s *apb,
i2s_callback_t callback, void *arg, uint32_t timeout)
{
struct sam_ssc_s *priv = (struct sam_ssc_s *)dev;
struct sam_buffer_s *bfcontainer;
irqstate_t flags;
int ret;
i2svdbg("buffer=%p nbytes=%d\n", buffer, (int)nbytes);
DEBUGASSERT(priv && buffer && ((uintptr_t)buffer & 3) == 0);
DEBUGASSERT(priv && apb && ((uintptr_t)apb->samp & 3) == 0);
i2svdbg("apb=%p nbytes=%d\n", apb, apb->nbytes);
#ifdef SSC_HAVE_TX
/* Allocate a buffer container in advance */
@ -2012,13 +2022,16 @@ static int ssc_send(struct i2s_dev_s *dev, const void *buffer,
goto errout_with_exclsem;
}
/* Add a reference to the audio buffer */
apb_reference(apb);
/* Initialize the buffer container structure */
bfcontainer->callback = (void *)callback;
bfcontainer->timeout = timeout;
bfcontainer->arg = arg;
bfcontainer->buffer = (void *)buffer;
bfcontainer->nbytes = nbytes;
bfcontainer->apb = apb;
bfcontainer->result = -EBUSY;
/* Add the buffer container to the end of the TX pending queue */

117
drivers/audio/i2schar.c
View File

@ -52,7 +52,6 @@
#include <string.h>
#include <debug.h>
#include <errno.h>
#include <queue.h>
#include <nuttx/kmalloc.h>
#include <nuttx/fs/fs.h>
@ -100,8 +99,6 @@ struct i2schar_dev_s
{
FAR struct i2s_dev_s *i2s; /* The lower half i2s driver */
sem_t exclsem; /* Assures mutually exclusive access */
dq_queue_t rxq; /* RX audio buffers awaiting transfer */
dq_queue_t txq; /* TX audio buffers awaiting transfer */
};
/****************************************************************************
@ -110,9 +107,9 @@ struct i2schar_dev_s
/* I2S callback function */
static void i2schar_rxcallback(FAR struct i2s_dev_s *dev,
FAR void *buffer, size_t nbytes, FAR void *arg, int result);
FAR struct ap_buffer_s *apb, FAR void *arg, int result);
static void i2schar_txcallback(FAR struct i2s_dev_s *dev,
FAR const void *buffer, size_t nbytes, FAR void *arg,
FAR struct ap_buffer_s *apb, FAR void *arg,
int result);
/* Character driver methods */
@ -161,47 +158,25 @@ static const struct file_operations i2schar_fops =
****************************************************************************/
static void i2schar_rxcallback(FAR struct i2s_dev_s *dev,
FAR void *buffer, size_t nbytes,
FAR struct ap_buffer_s *apb,
FAR void *arg, int result)
{
FAR struct i2schar_dev_s *priv = (FAR struct i2schar_dev_s *)arg;
FAR struct ap_buffer_s *apb;
i2svdbg("buffer=%p nbytes=%d result=%d\n", buffer, (int)nbytes, result);
DEBUGASSERT(dev && buffer && priv);
DEBUGASSERT(priv && apb);
i2svdbg("apb=%p nbytes=%d result=%d\n", apb, apb->nbytes, result);
/* The returned buffer should match the buffer at the head of the RX audio
* buffer queue.
/* REVISIT: If you want this to actually do something other than
* test I2S data transfer, then this is the point where you would
* want to pass the received I2S to some application.
*/
apb = (FAR struct ap_buffer_s *)dq_peek(&priv->rxq);
if ((FAR const void *)apb->samp != buffer)
{
i2sdbg("ERROR: apb=%p apb->samp=%p buffer=%p\n",
apb, apb->samp, buffer);
}
else
{
if (apb->nmaxbytes != nbytes)
{
i2sdbg("ERROR: apb->nmaxbytes=%d nbytes=%d\n",
(int)apb->nmaxbytes, (int)nbytes);
}
/* Release our reference to the audio buffer. Hopefully it will be freed
* now.
*/
/* REVISIT: If you want this to actually do something other than
* test I2S data transfer, then this is the point where you would
* want to pass the received I2S to some application.
*/
/* Remove the buffer from the beginning of the RX queue and release
* our reference to it. Hopefully it will be freed now.
*/
(void)dq_remfirst(&priv->rxq);
i2svdbg("Freeing apb=%p crefs=%d\n", apb, apb->crefs);
apb_free(apb);
}
i2svdbg("Freeing apb=%p crefs=%d\n", apb, apb->crefs);
apb_free(apb);
}
/****************************************************************************
@ -218,47 +193,25 @@ static void i2schar_rxcallback(FAR struct i2s_dev_s *dev,
****************************************************************************/
static void i2schar_txcallback(FAR struct i2s_dev_s *dev,
FAR const void *buffer, size_t nbytes,
FAR struct ap_buffer_s *apb,
FAR void *arg, int result)
{
FAR struct i2schar_dev_s *priv = (FAR struct i2schar_dev_s *)arg;
FAR struct ap_buffer_s *apb;
i2svdbg("buffer=%p nbytes=%d result=%d\n", buffer, (int)nbytes, result);
DEBUGASSERT(dev && buffer && priv);
DEBUGASSERT(priv && apb);
i2svdbg("apb=%p nbytes=%d result=%d\n", apb, apb->nbytes, result);
/* The returned buffer should match the buffer at the head of the RX audio
* buffer queue.
/* REVISIT: If you want this to actually do something other than
* test I2S data transfer, then this is the point where you would
* want to let some application know that the transfer has complete.
*/
apb = (FAR struct ap_buffer_s *)dq_peek(&priv->txq);
if ((FAR const void *)apb->samp != buffer)
{
i2sdbg("ERROR: apb=%p apb->samp=%p buffer=%p\n",
apb, apb->samp, buffer);
}
else
{
if (apb->nmaxbytes != nbytes)
{
i2sdbg("ERROR: apb->nmaxbytes=%d nbytes=%d\n",
(int)apb->nmaxbytes, (int)nbytes);
}
/* Release our reference to the audio buffer. Hopefully it will be freed
* now.
*/
/* REVISIT: If you want this to actually do something other than
* test I2S data transfer, then this is the point where you would
* want to pass the received I2S to some application.
*/
/* Remove the buffer from the beginning of the RX queue and release
* our reference to it. Hopefully it will be freed now.
*/
(void)dq_remfirst(&priv->txq);
i2svdbg("Freeing apb=%p crefs=%d\n", apb, apb->crefs);
apb_free(apb);
}
i2svdbg("Freeing apb=%p crefs=%d\n", apb, apb->crefs);
apb_free(apb);
}
/****************************************************************************
@ -298,7 +251,7 @@ static ssize_t i2schar_read(FAR struct file *filep, FAR char *buffer,
nbytes = apb->nmaxbytes;
DEBUGASSERT(buflen >= (sizeof(struct ap_buffer_s) + nbytes));
/* Add our buffer reference */
/* Add a reference to the audio buffer */
apb_reference(apb);
@ -313,13 +266,9 @@ static ssize_t i2schar_read(FAR struct file *filep, FAR char *buffer,
goto errout_with_reference;
}
/* Add the audio buffer to the I2S receiver queue */
dq_addlast(&apb->dq_entry, &priv->rxq);
/* Give the buffer to the I2S driver */
/* And give the buffer to the I2S driver */
ret = I2S_RECEIVE(priv->i2s, apb->samp, nbytes, i2schar_rxcallback, priv, 0);
ret = I2S_RECEIVE(priv->i2s, apb, i2schar_rxcallback, priv, 0);
if (ret < 0)
{
i2sdbg("ERROR: I2S_RECEIVE returned: %d\n", ret);
@ -376,7 +325,7 @@ static ssize_t i2schar_write(FAR struct file *filep, FAR const char *buffer,
nbytes = apb->nmaxbytes;
DEBUGASSERT(buflen >= (sizeof(struct ap_buffer_s) + nbytes));
/* Add our buffer reference */
/* Add a reference to the audio buffer */
apb_reference(apb);
@ -391,13 +340,9 @@ static ssize_t i2schar_write(FAR struct file *filep, FAR const char *buffer,
goto errout_with_reference;
}
/* Add the audio buffer to the I2S transmitter queue */
dq_addlast(&apb->dq_entry, &priv->txq);
/* Give the audio buffer to the I2S driver */
/* And give the buffer to the I2S driver */
ret = I2S_SEND(priv->i2s, apb->samp, nbytes, i2schar_txcallback, priv, 0);
ret = I2S_SEND(priv->i2s, apb, i2schar_txcallback, priv, 0);
if (ret < 0)
{
i2sdbg("ERROR: I2S_SEND returned: %d\n", ret);
@ -457,8 +402,6 @@ int i2schar_register(FAR struct i2s_dev_s *i2s, int minor)
priv->i2s = i2s;
sem_init(&priv->exclsem, 0, 1);
dq_init(&priv->rxq);
dq_init(&priv->txq);
/* Create the character device name */

35
include/nuttx/audio/i2s.h
View File

@ -46,6 +46,8 @@
#include <stdint.h>
#include <stdbool.h>
#include <nuttx/audio/audio.h>
#ifdef CONFIG_I2S
/****************************************************************************
@ -99,9 +101,7 @@
*
* Input Parameters:
* dev - Device-specific state data
* buffer - A pointer to the buffer in which to recieve data
* nbytes - The length of data that can be received in the buffer in number
* of bytes.
* apb - A pointer to the audio buffer in which to recieve data
* callback - A user provided callback function that will be called at
* the completion of the transfer. The callback will be
* performed in the context of the worker thread.
@ -123,7 +123,7 @@
*
****************************************************************************/
#define I2S_RECEIVE(d,b,n,c,a,t) ((d)->ops->i2s_receive(d,b,n,c,a,t))
#define I2S_RECEIVE(d,b,c,a,t) ((d)->ops->i2s_receive(d,b,c,a,t))
/****************************************************************************
* Name: I2S_TXSAMPLERATE
@ -170,9 +170,8 @@
* Send a block of data on I2S.
*
* Input Parameters:
* dev - Device-specific state data
* buffer - A pointer to the buffer of data to be sent
* nbytes - the length of data to send from the buffer in number of bytes.
* dev - Device-specific state data
* apb - A pointer to the audio buffer from which to send data
* callback - A user provided callback function that will be called at
* the completion of the transfer. The callback will be
* performed in the context of the worker thread.
@ -194,7 +193,7 @@
*
****************************************************************************/
#define I2S_SEND(d,b,n,c,a,t) ((d)->ops->i2s_send(d,b,n,c,a,t))
#define I2S_SEND(d,b,c,a,t) ((d)->ops->i2s_send(d,b,c,a,t))
/****************************************************************************
* Public Types
@ -202,12 +201,8 @@
/* Transfer complete callbacks */
struct i2s_dev_s;
typedef CODE void (*i2s_rxcallback_t)(FAR struct i2s_dev_s *dev,
FAR void *buffer, size_t nbytes, FAR void *arg,
int result);
typedef CODE void (*i2s_txcallback_t)(FAR struct i2s_dev_s *dev,
FAR const void *buffer, size_t nbytes, FAR void *arg,
int result);
typedef CODE void (*i2s_callback_t)(FAR struct i2s_dev_s *dev,
FAR struct ap_buffer_s *apb, FAR void *arg, int result);
/* The I2S vtable */
@ -217,17 +212,17 @@ struct i2s_ops_s
CODE uint32_t (*i2s_rxsamplerate)(FAR struct i2s_dev_s *dev, uint32_t rate);
CODE uint32_t (*i2s_rxdatawidth)(FAR struct i2s_dev_s *dev, int bits);
CODE int (*i2s_receive)(FAR struct i2s_dev_s *dev, FAR void *buffer,
size_t nbytes, i2s_rxcallback_t callback, FAR void *arg,
uint32_t timeout);
CODE int (*i2s_receive)(FAR struct i2s_dev_s *dev,
FAR struct ap_buffer_s *apb, i2s_callback_t callback,
FAR void *arg, uint32_t timeout);
/* Transmitter methods */
CODE uint32_t (*i2s_txsamplerate)(FAR struct i2s_dev_s *dev, uint32_t rate);
CODE uint32_t (*i2s_txdatawidth)(FAR struct i2s_dev_s *dev, int bits);
CODE int (*i2s_send)(FAR struct i2s_dev_s *dev, FAR const void *buffer,
size_t nbytes, i2s_txcallback_t callback, FAR void *arg,
uint32_t timeout);
CODE int (*i2s_send)(FAR struct i2s_dev_s *dev,
FAR struct ap_buffer_s *apb, i2s_callback_t callback,
FAR void *arg, uint32_t timeout);
};
/* I2S private data. This structure only defines the initial fields of the