AVR Freaks

I am using the ASF 4 EFC driver routines to write to internal flash on a SAMv71.  I registered a callback so that I can tell when the Flash is ready to accept a new command. Before a flash_write I set m_bReady to false (busy). The callback routine sets m_bReady to true.

The problem is that as soon as I do a flash_register_callback(),  the flash FRDY bit is already set (since the flash is ready) and this generates an immediate interrupt.  EFC_Handler() (in hap_efc.c) then calls the callback.  Once the callback is executed, the FRDY bit is still true, so it keeps calling the callback routine continuously and the program is hung.

Am I doing this wrong or is this just an ASF driver bug?

void flash_callback(struct flash_descriptor *const descr);

bool     m_bReady;

InternalFlashDriver::InternalFlashDriver()
{
    m_ui32PageSize = flash_get_page_size(&FLASH_0);
    flash_register_callback(&FLASH_0, FLASH_CB_READY, flash_callback);
    m_bReady = true;
}


void InternalFlashDriver::flash_callback(struct flash_descriptor *const descr)
{
   m_bReady = true;
}

bool InternalFlashDriver::WritePage(uint8_t * pData, uint32_t ui32Address)
{
    bool bFlag = false;

    if (m_bReady == true)
    {
        m_bReady = false;                                       // Set flash busy
        if (flash_write(&FLASH_0, ui32Address, pData, m_ui32PageSize) != ERR_NONE)
        {
            bFlag = true;                                       // Error
        }
    }
    else
    {
        bFlag = true;                                           // Flash not ready
    }

    return(bFlag);
}

----------------------------

In hpl_efc.c

void EFC_Handler(void)
{
	void *const hw = _efc_dev->hw;

	if (hri_efc_get_EEFC_FSR_FRDY_bit(hw)) {
		if (NULL != _efc_dev->flash_cb.ready_cb) {
			_efc_dev->flash_cb.ready_cb(_efc_dev);
		}
	}
}