On Wed, Sep 10, 2014 at 09:18:52PM -0500, Andy Gross wrote:

> +static int adm_slave_config(struct adm_chan *achan,
> +             struct dma_slave_config *cfg)
> +{
> +     int ret = 0;
> +     u32 burst;
> +     struct adm_device *adev = achan->adev;
> +
> +     memcpy(&achan->slave, cfg, sizeof(*cfg));
> +
> +     /* set channel CRCI burst, if applicable */
> +     if (achan->crci) {
> +             burst = max_t(u32, cfg->src_maxburst, cfg->dst_maxburst);
> +
> +             switch (burst) {
> +             case 16:
> +                     achan->blk_size = 0;
> +                     break;
> +             case 32:
> +                     achan->blk_size = 1;
> +                     break;
> +             case 64:
> +                     achan->blk_size = 2;
> +                     break;
> +             case 128:
> +                     achan->blk_size = 3;
> +                     break;
> +             case 192:
> +                     achan->blk_size = 4;
> +                     break;
> +             case 256:
> +                     achan->blk_size = 5;
> +                     break;
> +             default:
> +                     achan->slave.src_maxburst = 0;
> +                     achan->slave.dst_maxburst = 0;
Why clear these for error cases
> +                     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?

> +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

> +     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
> +
> +     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 [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to