Please refer to this thread that, for some reason, @FBL accepted as an answer (it is not) https://community.st.com/t5/stm32-mcus-embedded-software/usbx-audio-class-frame-done-callback-not-called/td-p/855262
I'm seeing that when I try to start an audio flux from my PC to the USB Audio driver, I'm seeing the error handler being called with the following stack:
status = _ux_device_stack_transfer_request(transfer, max_packet_size, max_packet_size);
triggers the error as the status is 38 (what does it mean?). Inside the function, I've found
status = dcd -> ux_slave_dcd_function(dcd, UX_DCD_TRANSFER_REQUEST, transfer_request);
which is the one that returns 38.
In ux_api.h, the only value I was able to find that matches the return value was
#define UX_TRANSFER_BUS_RESET 0x26
From here, I'm stuck as the ux_slave_dcd_function is defined as
typedef struct UX_SLAVE_DCD_STRUCT
{
UINT ux_slave_dcd_status;
UINT ux_slave_dcd_controller_type;
UINT ux_slave_dcd_otg_capabilities;
UINT ux_slave_dcd_irq;
ULONG ux_slave_dcd_io;
ULONG ux_slave_dcd_device_address;
UINT (*ux_slave_dcd_function) (struct UX_SLAVE_DCD_STRUCT *,UINT, VOID *);
void *ux_slave_dcd_controller_hardware;
} UX_SLAVE_DCD;
