Re: [PATCH v2] dmaengine: at_xdmac: rework slave configuration part

From: Ludovic Desroches
Date: Wed Jun 03 2015 - 04:27:56 EST


On Tue, Jun 02, 2015 at 06:52:08PM +0530, Vinod Koul wrote:
> On Mon, Jun 01, 2015 at 05:40:48PM +0200, Ludovic Desroches wrote:
> > @@ -604,16 +636,18 @@ at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
> > return NULL;
> > }
> >
> > + if (at_xdmac_compute_chan_conf(chan, direction))
> > + return NULL;
> > +
> You forgot to release the lock. Also in prev call, you are getting the desc,
> that needs to be put back or moved before getting descriptor
>

Right, thanks.

> > /* Linked list descriptor setup. */
> > if (direction == DMA_DEV_TO_MEM) {
> > - desc->lld.mbr_sa = atchan->per_src_addr;
> > + desc->lld.mbr_sa = atchan->sconfig.src_addr;
> > desc->lld.mbr_da = mem;
> > - desc->lld.mbr_cfg = atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG];
> > } else {
> > desc->lld.mbr_sa = mem;
> > - desc->lld.mbr_da = atchan->per_dst_addr;
> > - desc->lld.mbr_cfg = atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG];
> > + desc->lld.mbr_da = atchan->sconfig.dst_addr;
> > }
> > + desc->lld.mbr_cfg = atchan->cfg;
> > dwidth = at_xdmac_get_dwidth(desc->lld.mbr_cfg);
> > fixed_dwidth = IS_ALIGNED(len, 1 << dwidth)
> > ? at_xdmac_get_dwidth(desc->lld.mbr_cfg)
> > @@ -696,15 +730,17 @@ at_xdmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr,
> > "%s: desc=0x%p, tx_dma_desc.phys=%pad\n",
> > __func__, desc, &desc->tx_dma_desc.phys);
> >
> > + if (at_xdmac_compute_chan_conf(chan, direction))
> > + return NULL;
> same here as well
>

In this case, lock is already released when doing this call but I
have to put back the descriptor.

Will send a v3.


Ludovic
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