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    SubjectRe: [PATCH v2 2/2] dmaengine: Add support for multiple descriptors for imx-dma.
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    Hi Sascha,

    On 1 March 2012 11:19, Sascha Hauer <s.hauer@pengutronix.de> wrote:
    > On Tue, Feb 28, 2012 at 05:08:18PM +0100, Javier Martin wrote:
    >> dmaengine specifies the possibility that several descriptors
    >> can be queued for transfer. It also indicates that tasklets
    >> must be used for DMA callbacks.
    >>
    >> Signed-off-by: Javier Martin <javier.martin@vista-silicon.com>
    >
    > Have you tested this patch with audio?

    Yes,
    I have a test battery which tests audio, mmc, runs dmatest module and
    a custom mem2mem video device I'm developing.

    >
    >> +static int imxdma_xfer_desc(struct imxdma_desc *d)
    >> +{
    >> +     struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
    >> +     int ret;
    >> +
    >> +     /* Configure and enable */
    >> +     switch (d->type) {
    >> +     case IMXDMA_DESC_MEMCPY:
    >> +             ret = imx_dma_config_channel(imxdmac->imxdma_channel,
    >> +                                       d->config_port, d->config_mem, 0, 0);
    >> +             if (ret < 0)
    >> +                     return ret;
    >> +             ret = imx_dma_setup_single(imxdmac->imxdma_channel, d->src,
    >> +                                        d->len, d->dest, d->dmamode);
    >> +             if (ret < 0)
    >> +                     return ret;
    >> +             break;
    >> +     case IMXDMA_DESC_CYCLIC:
    >> +             ret = imx_dma_setup_progression_handler(imxdmac->imxdma_channel,
    >> +                                                     imxdma_progression);
    >> +             if (ret < 0)
    >> +                     return ret;
    >
    > You fall through here. Is this intended? If yes, a comment would be good
    > here.

    Yes it is. cyclic is the same as slave_sg with the add-on of the
    progression handler and a specific configuration of the sglist which
    is done in 'imxdma_prep_dma_cyclic'.
    Do you want me to send a new version with a comment on the matter?

    --
    Javier Martin
    Vista Silicon S.L.
    CDTUC - FASE C - Oficina S-345
    Avda de los Castros s/n
    39005- Santander. Cantabria. Spain
    +34 942 25 32 60
    www.vista-silicon.com
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