[alsa-devel] [PATCH V2 REPOST] ASoC: dmaengine: support deferred probe for DMA channels

[Lars-Peter Clausen]

On 12/10/2013 06:59 PM, Stephen Warren wrote:
> From: Stephen Warren <swarren at nvidia.com>
> 
> Enhance dmaengine_pcm_request_chan_of() to support deferred probe for
> DMA channels, by using the new dma_request_slave_channel_or_err() API.
> This prevents snd_dmaengine_pcm_register() from succeeding without
> acquiring DMA channels due to the relevant DMA controller not yet being
> registered.
> 
> Signed-off-by: Stephen Warren <swarren at nvidia.com>
> Acked-by: Lars-Peter Clausen <lars at metafoo.de>

Still looks good, but one nitpick:

> -		pcm->chan[i] = dma_request_slave_channel(dev, name);
> +		chan = dma_request_slave_channel_reason(dev, name);
> +		if (IS_ERR(chan)) {
> +			if (PTR_ERR(pcm->chan[i]) == -EPROBE_DEFER)
> +				return -EPROBE_DEFER;
> +			pcm->chan[i] = NULL;
> +		} else
> +			pcm->chan[i] = chan;

I think checkpatch will complain about the above. There should be brackets
around the else branch.

>  		if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
>  			break;
>  	}
>  
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