Function a10codec_chan_init

freebsd/arm/allwinner/a10_codec.c:811–869

}

static void *
a10codec_chan_init(kobj_t obj, void *devinfo, struct snd_dbuf *b,
    struct pcm_channel *c, int dir)
{
	struct a10codec_info *sc = devinfo;
	struct a10codec_chinfo *ch = dir == PCMDIR_PLAY ? &sc->play : &sc->rec;
	phandle_t xref;
	pcell_t *cells;
	int ncells, error;

	error = ofw_bus_parse_xref_list_alloc(ofw_bus_get_node(sc->dev),
	    "dmas", "#dma-cells", dir == PCMDIR_PLAY ? 1 : 0,
	    &xref, &ncells, &cells);
	if (error != 0) {
		device_printf(sc->dev, "cannot parse 'dmas' property\n");
		return (NULL);
	}
	OF_prop_free(cells);

	ch->parent = sc;
	ch->channel = c;
	ch->buffer = b;
	ch->dir = dir;
	ch->fifo = rman_get_start(sc->res[0]) +
	    (dir == PCMDIR_REC ? AC_ADC_RXDATA(sc) : AC_DAC_TXDATA(sc));

	ch->dmac = OF_device_from_xref(xref);
	if (ch->dmac == NULL) {
		device_printf(sc->dev, "cannot find DMA controller\n");
		device_printf(sc->dev, "xref = 0x%x\n", (u_int)xref);
		return (NULL);
	}
	ch->dmachan = SUNXI_DMA_ALLOC(ch->dmac, false, a10codec_dmaintr, ch);
	if (ch->dmachan == NULL) {
		device_printf(sc->dev, "cannot allocate DMA channel\n");
		return (NULL);
	}

	error = bus_dmamem_alloc(sc->dmat, &ch->dmaaddr,
	    BUS_DMA_NOWAIT | BUS_DMA_COHERENT, &ch->dmamap);
	if (error != 0) {
		device_printf(sc->dev, "cannot allocate channel buffer\n");
		return (NULL);
	}
	error = bus_dmamap_load(sc->dmat, ch->dmamap, ch->dmaaddr,
	    sc->dmasize, a10codec_dmamap_cb, ch, BUS_DMA_NOWAIT);
	if (error != 0) {
		device_printf(sc->dev, "cannot load DMA map\n");
		return (NULL);
	}
	memset(ch->dmaaddr, 0, sc->dmasize);

	if (sndbuf_setup(ch->buffer, ch->dmaaddr, sc->dmasize) != 0) {
		device_printf(sc->dev, "cannot setup sndbuf\n");
		return (NULL);
	}

	return (ch);