static ssize_t i2schar_write(FAR struct file *filep, FAR const char *buffer,
size_t buflen)
{
FAR struct inode *inode = filep->f_inode;
FAR struct i2schar_dev_s *priv;
FAR struct ap_buffer_s *apb;
size_t nbytes;
int ret;
i2svdbg("buffer=%p buflen=%d\n", buffer, (int)buflen);
/* Get our private data structure */
DEBUGASSERT(filep && buffer);
inode = filep->f_inode;
DEBUGASSERT(inode);
priv = (FAR struct i2schar_dev_s *)inode->i_private;
DEBUGASSERT(priv);
/* Verify that the buffer refers to one, correctly sized audio buffer */
DEBUGASSERT(buflen >= sizeof(struct ap_buffer_s));
apb = (FAR struct ap_buffer_s *)buffer;
nbytes = apb->nmaxbytes;
DEBUGASSERT(buflen >= (sizeof(struct ap_buffer_s) + nbytes));
/* Add a reference to the audio buffer */
apb_reference(apb);
/* Get exclusive access to i2c character driver */
ret = sem_wait(&priv->exclsem);
if (ret < 0)
{
ret = -errno;
DEBUGASSERT(ret < 0);
i2sdbg("ERROR: sem_wait returned: %d\n", ret);
goto errout_with_reference;
}
/* Give the audio buffer to the I2S driver */
ret = I2S_SEND(priv->i2s, apb, i2schar_txcallback, priv,
CONFIG_AUDIO_I2SCHAR_TXTIMEOUT);
if (ret < 0)
{
i2sdbg("ERROR: I2S_SEND returned: %d\n", ret);
goto errout_with_reference;
}
/* Lie to the caller and tell them that all of the bytes have been
* sent.
*/
sem_post(&priv->exclsem);
return sizeof(struct ap_buffer_s) + nbytes;
errout_with_reference:
apb_free(apb);
sem_post(&priv->exclsem);
return ret;
}
static ssize_t i2schar_read(FAR struct file *filep, FAR char *buffer,
size_t buflen)
{
FAR struct inode *inode;
FAR struct i2schar_dev_s *priv;
FAR struct ap_buffer_s *apb;
size_t nbytes;
int ret;
i2sinfo("buffer=%p buflen=%d\n", buffer, (int)buflen);
/* Get our private data structure */
DEBUGASSERT(filep != NULL && buffer != NULL);
inode = filep->f_inode;
DEBUGASSERT(inode != NULL);
priv = (FAR struct i2schar_dev_s *)inode->i_private;
DEBUGASSERT(priv != NULL);
/* Verify that the buffer refers to one, correctly sized audio buffer */
DEBUGASSERT(buflen >= sizeof(struct ap_buffer_s));
apb = (FAR struct ap_buffer_s *)buffer;
nbytes = apb->nmaxbytes;
DEBUGASSERT(buflen >= (sizeof(struct ap_buffer_s) + nbytes));
/* Add a reference to the audio buffer */
apb_reference(apb);
/* Get exclusive access to i2c character driver */
ret = nxsem_wait(&priv->exclsem);
if (ret < 0)
{
i2serr("ERROR: nxsem_wait returned: %d\n", ret);
goto errout_with_reference;
}
/* Give the buffer to the I2S driver */
ret = I2S_RECEIVE(priv->i2s, apb, i2schar_rxcallback, priv,
CONFIG_AUDIO_I2SCHAR_RXTIMEOUT);
if (ret < 0)
{
i2serr("ERROR: I2S_RECEIVE returned: %d\n", ret);
goto errout_with_reference;
}
/* Lie to the caller and tell them that all of the bytes have been
* received
*/
nxsem_post(&priv->exclsem);
return sizeof(struct ap_buffer_s) + nbytes;
errout_with_reference:
apb_free(apb);
nxsem_post(&priv->exclsem);
return ret;
}
