I am trying to use the i2s_demo code on a K70 board and MQX 4.1. It's all going well until the first write() to the sai1: device. In the "play" shell command there is this loop:
/* Play a file */
printf(" Playing a file...");
while (!feof(file_ptr))
{
requested = fread(data, 1, block_size, file_ptr);
if (ferror(file_ptr) && !(feof(file_ptr)))
{
printf("\n Error reading from a file %s.\n", argv[2]);
break;
}
write(device_ptr, data, requested);
}
Line 13 above is going to end up calling _io_sai_int_write() below:
_mqx_int _io_sai_int_write
(
/* [IN] the handle returned from _fopen */
MQX_FILE_PTR fd_ptr,
/* [IN] where the data are to be stored */
char *data_ptr,
/* [IN] the number of bytes to read */
_mqx_int n
)
{ /* Body */
IO_DEVICE_STRUCT_PTR io_dev_ptr;
IO_SAI_DEVICE_STRUCT_PTR io_sai_dev_ptr;
uint32_t result;
io_dev_ptr = (IO_DEVICE_STRUCT_PTR)fd_ptr->DEV_PTR;
io_sai_dev_ptr = (void *)io_dev_ptr->DRIVER_INIT_PTR;
_lwsem_wait(&io_sai_dev_ptr->LWSEM);
result = (*io_sai_dev_ptr->DEV_WRITE)(io_sai_dev_ptr, data_ptr, n);
_lwsem_post(&io_sai_dev_ptr->LWSEM);
return result;
} /* Endbody */
In line 22 in _io_sai_int_write() above, (*io_sai_dev_ptr->DEV_WRITE) is 0x00000000 !!
That's because in init_sai.c in the BSP the read and write function pointers are set to NULL:
const SAI_INIT_STRUCT _bsp_sai_init =
{
"sai1:",
_ksai_dma_init,
_ksai_dma_deinit,
NULL,
NULL,
_ksai_dma_ioctl,
&_bsp_ksai_init
};
What's going on with this demo?
Paul
