AT_XDMAC_CNDA
check_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
cur_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
atchan->save_cnda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA);
at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, atchan->save_cnda);
at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, reg);
at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),