[PATCH] mmc: mxs-mmc: add support for pre_req and post_req

[Shawn Guo]

On Wed, Apr 20, 2011 at 09:58:48AM +0200, Per Forlin wrote:
> >  static struct dma_async_tx_descriptor *mxs_mmc_prep_dma(
> >        struct mxs_mmc_host *host, unsigned int append)
> >  {
> > @@ -312,8 +342,8 @@ static struct dma_async_tx_descriptor *mxs_mmc_prep_dma(
> >
> >        if (data) {
> >                /* data */
> > -               dma_map_sg(mmc_dev(host->mmc), data->sg,
> > -                          data->sg_len, host->dma_dir);
> > +               if (mxs_mmc_prep_dma_data(host, data, NULL))
> > +                       return NULL;
> >                sgl = data->sg;
> >                sg_len = data->sg_len;
> >        } else {
> > @@ -328,9 +358,11 @@ static struct dma_async_tx_descriptor *mxs_mmc_prep_dma(
> >                desc->callback = mxs_mmc_dma_irq_callback;
> >                desc->callback_param = host;
> >        } else {
> > -               if (data)
> > +               if (data) {
> >                        dma_unmap_sg(mmc_dev(host->mmc), data->sg,
> >                                     data->sg_len, host->dma_dir);
> > +                       data->host_cookie = 0;
> > +               }
> When is dma_unmap_sg called? If host_cookie is set dma_unmap() should
> only be called from post_req.
> My guess is
> + if (data && !data->host_cookie) {
> It looks like only dma_map is run in parallel with transfer but not
> dma_unmap. This may explain the numbers.

Good catch.  I forgot patching mxs_mmc_request_done where dma_unmap_sg
is called.  Will correct and retest ...

-- 
Regards,
Shawn