ppc440spe_chan_get_current_descriptor
cur_desc = ppc440spe_chan_get_current_descriptor(chan);
desc->phys == ppc440spe_chan_get_current_descriptor(chan))
u32 current_desc = ppc440spe_chan_get_current_descriptor(chan);
ppc440spe_chan_get_current_descriptor(struct ppc440spe_adma_chan *chan);