<snip> > > + break; > > + default: > > + achan->slave.src_maxburst = 0; > > + achan->slave.dst_maxburst = 0; > Why clear these for error cases With the return I shouldn't need to. I'll fix this. > > + ret = -EINVAL; > > + break; > > + } > > + > > + if (!ret) > > + writel(achan->blk_size, > > + adev->regs + HI_CRCI_CTL(achan->id, adev->ee)); > and why do we write to HW on this. Shouldn't this be done when you program > the descriptor? It could be deferred to later. The main point is that I don't see the slave_config happening every transaction. I was only modifying it now instead of making a register write for every transaction. > > > +static enum dma_status adm_tx_status(struct dma_chan *chan, dma_cookie_t cookie, > > + struct dma_tx_state *txstate) > > +{ > > + struct adm_chan *achan = to_adm_chan(chan); > > + struct virt_dma_desc *vd; > > + enum dma_status ret; > > + unsigned long flags; > > + size_t residue = 0; > > + > > + ret = dma_cookie_status(chan, cookie, txstate); > > + > Last arg can be null to this, so before you do residue calcluation and block > interrupts would make sense to return from here if arg is NULL Good catch. Will fix. > > > + spin_lock_irqsave(&achan->vc.lock, flags); > > + > > + vd = vchan_find_desc(&achan->vc, cookie); > > + if (vd) > > + residue = container_of(vd, struct adm_async_desc, vd)->length; > > + else if (achan->curr_txd && achan->curr_txd->vd.tx.cookie == cookie) > > + residue = achan->curr_txd->length; > so this is current cookie, so you need to read from HW on current position There is no way to get current position unfortunately without relying on unreliable debug registers. > > + > > + spin_unlock_irqrestore(&achan->vc.lock, flags); > > + > > + dma_set_residue(txstate, residue); > > + > > + if (achan->error) > > + return DMA_ERROR; > > + > > + return ret; > > -- > ~Vinod > > -- > To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- sent by an employee of the Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by The Linux Foundation -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html