to_hsdma_vchan
hvc = to_hsdma_vchan(cb->vd->tx.chan);
struct mtk_hsdma_vchan *hvc = to_hsdma_vchan(c);
struct mtk_hsdma_vchan *hvc = to_hsdma_vchan(c);
struct mtk_hsdma_vchan *hvc = to_hsdma_vchan(c);
struct mtk_hsdma_vchan *hvc = to_hsdma_vchan(c);