Hi Vinod/Lars, On 11/26/14, Padmavathi Venna <padma.v@xxxxxxxxxxx> wrote: > Fill txstate.residue with the amount of bytes remaining in the current > transfer if the transfer is not complete. This will be of particular > use to i2s DMA transfers, providing more accurate hw_ptr values to ASoC. > > I had taken the code from Dylan Reid <dgreid@xxxxxxxxxxxx> patch from the > below link and modified according to the current dmaengine framework. > http://comments.gmane.org/gmane.linux.kernel.samsung-soc/23007 > > Cc: Dylan Reid <dgreid@xxxxxxxxxxxx> > Signed-off-by: Padmavathi Venna <padma.v@xxxxxxxxxxx> > --- > > This patch has been tested for audio playback on exynos5420 peach-pit. > > drivers/dma/pl330.c | 67 > +++++++++++++++++++++++++++++++++++++++++++++++++- > 1 files changed, 65 insertions(+), 2 deletions(-) > > diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c > index b7493d2..db880ae 100644 > --- a/drivers/dma/pl330.c > +++ b/drivers/dma/pl330.c > @@ -2182,11 +2182,74 @@ static void pl330_free_chan_resources(struct > dma_chan *chan) > pm_runtime_put_autosuspend(pch->dmac->ddma.dev); > } > > +static inline int > +pl330_src_addr_in_desc(struct dma_pl330_desc *desc, unsigned int sar) > +{ > + return ((desc->px.src_addr <= sar) && > + (sar <= (desc->px.src_addr + desc->px.bytes))); > +} > + > +static inline int > +pl330_dst_addr_in_desc(struct dma_pl330_desc *desc, unsigned int dar) > +{ > + return ((desc->px.dst_addr <= dar) && > + (dar <= (desc->px.dst_addr + desc->px.bytes))); > +} > + > static enum dma_status > pl330_tx_status(struct dma_chan *chan, dma_cookie_t cookie, > struct dma_tx_state *txstate) > { > - return dma_cookie_status(chan, cookie, txstate); > + dma_addr_t sar, dar; > + struct dma_pl330_chan *pch = to_pchan(chan); > + void __iomem *regs = pch->dmac->base; > + struct pl330_thread *thrd = pch->thread; > + struct dma_pl330_desc *desc; > + unsigned int residue = 0; > + unsigned long flags; > + bool first = true; > + dma_cookie_t first_c, current_c; > + dma_cookie_t used; > + enum dma_status ret; > + > + ret = dma_cookie_status(chan, cookie, txstate); > + if (ret == DMA_COMPLETE || !txstate) > + return ret; > + > + used = txstate->used; > + > + spin_lock_irqsave(&pch->lock, flags); > + sar = readl(regs + SA(thrd->id)); > + dar = readl(regs + DA(thrd->id)); > + > + list_for_each_entry(desc, &pch->work_list, node) { > + if (desc->status == BUSY) { > + current_c = desc->txd.cookie; > + if (first) { > + first_c = desc->txd.cookie; > + first = false; > + } > + > + if (first_c < current_c) > + residue += desc->px.bytes; > + else { > + if (desc->rqcfg.src_inc && pl330_src_addr_in_desc(desc, sar)) { > + residue += desc->px.bytes; > + residue -= sar - desc->px.src_addr; > + } else if (desc->rqcfg.dst_inc && pl330_dst_addr_in_desc(desc, dar)) { > + residue += desc->px.bytes; > + residue -= dar - desc->px.dst_addr; > + } > + } > + } else if (desc->status == PREP) > + residue += desc->px.bytes; > + > + if (desc->txd.cookie == used) > + break; > + } > + spin_unlock_irqrestore(&pch->lock, flags); > + dma_set_residue(txstate, residue); > + return ret; > } > > static void pl330_issue_pending(struct dma_chan *chan) > @@ -2631,7 +2694,7 @@ static int pl330_dma_device_slave_caps(struct dma_chan > *dchan, > caps->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); > caps->cmd_pause = false; > caps->cmd_terminate = true; > - caps->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR; > + caps->residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT; > > return 0; > } Any comment on this patch? Thanks Padma > -- > 1.7.4.4 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" > in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html