Re: [alsa-devel] [PATCH 2/2] ASoC: atmel-pcm: use generic dmaengine framework

[Bo Shen <voice.shen@xxxxxxxxx>]

Hi Lars-Peter,

On 7/2/2013 23:34, Lars-Peter Clausen wrote:
> On 07/02/2013 11:04 AM, Bo Shen wrote:
> [...]
> > -/*--------------------------------------------------------------------------*\
> > - * DMAENGINE operations
> > -\*--------------------------------------------------------------------------*/
> > -static bool filter(struct dma_chan *chan, void *slave)
> > -{
> > -	struct at_dma_slave *sl = slave;
> > -
> > -	if (sl->dma_dev == chan->device->dev) {
> > -		chan->private = sl;
> > -		return true;
> > -	} else {
> > -		return false;
> > -	}
> > -}
>
> I'm wondering why is filtering no longer required?

Now this is handled by at_dma_filter in at_hdmac driver. More 
information, you can reference: <driver/dma/at_hdmac.c> file

> [...]
> > +		slave_config->dst_addr = (dma_addr_t)ssc->phybase + SSC_THR;
> [...]
> > +		slave_config->src_addr = (dma_addr_t)ssc->phybase + SSC_RHR;
>
> Change the type of phybase to dma_addr_t

It should be:
slave_config->dst_addr = (dma_addr_t)(ssc->phybase + SSC_THR);
slave_config->src_addr = (dma_addr_t)(ssc->phybase + SSC_RHR);

> [...]
> >   }
> >
> > -static int atmel_pcm_dma_prepare(struct snd_pcm_substream *substream)
> > -{
> > -	struct snd_soc_pcm_runtime *rtd = substream->private_data;
> > -	struct atmel_pcm_dma_params *prtd;
> > -
> > -	prtd = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
> > -
> > -	ssc_writex(prtd->ssc->regs, SSC_IER, prtd->mask->ssc_error);
> > -	ssc_writex(prtd->ssc->regs, SSC_CR, prtd->mask->ssc_enable);
>
> These writes are also completely lost

This will be moved to DAI driver startup callback function.

> > -
> > -	return 0;
> > -}
>
> I think it would also be good to get rid of any references to the ssc struct
> from the DMA driver and move them over to the DAI driver.

I will try to implement this in next version patch.

Thanks.

> - Lars

Best Regards,
Bo Shen

--
To unsubscribe from this list: send the line "unsubscribe linux-sound" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html