cpsw_tx_handler
cpsw->txv[0].ch = cpdma_chan_create(cpsw->dma, ch, cpsw_tx_handler, 0);
handler = cpsw_tx_handler;
cpsw->txv[0].ch = cpdma_chan_create(cpsw->dma, ch, cpsw_tx_handler, 0);
void cpsw_tx_handler(void *token, int len, int status);