[alsa-devel] [PATCH 2/3] ASoC: ux500_pcm: Differentiate between pdata and DT initialisation

[Lars-Peter Clausen]

On 12/03/2013 09:36 AM, Lee Jones wrote:
> On Mon, 02 Dec 2013, Lars-Peter Clausen wrote:
>
>> On 12/02/2013 07:00 PM, Lee Jones wrote:
>>> If booting with full DT support (i.e. DMA too, the last piece of the
>>> puzzle), then we don't need to use the compatible request channel call
>>> back. We also require slightly different flags to inform the core that
>>> we are booting with DT.
>>
>> I don't think you need differentiate between DT and non-DT here.
>> If the SND_DMAENGINE_PCM_FLAG_COMPAT is set and the
>> SND_DMAENGINE_PCM_FLAG_NO_DT is not set it will first try to request the
>> channels from the DT if that fails it will fallback to the compat path. So
>> all this patch needs to do is remove the SND_DMAENGINE_PCM_FLAG_NO_DT, that
>> should be it.
>
> I have no way of testing that, as we are currently 80% through
> shutting down platform data altogether. In fact, I think there is only
> ASoC to be converted. Most of this stuff is going to be ripped out
> within the next couple of weeks in any case. It will happen as soon as
> I can find an hour or two to work on it.
>
> For that reason I didn't want to disturb the current semantics. I've
> already found that a bunch of he generic (oh, you can just use the
> central) functions (for that) don't actually work for us for one
> reason or another.

All SND_DMAENGINE_PCM_FLAG_NO_DT does is to skip trying to request the channel 
from the dt. If of_node is NULL this step will be skipped anyway. So only 
setting SND_DMAENGINE_PCM_FLAG_NO_DT if we already know that the node is NULL 
is redundant.

>
>>> Cc: alsa-devel at alsa-project.org
>>> Acked-by: Linus Walleij <linus.walleij at linaro.org>
>>> Signed-off-by: Lee Jones <lee.jones at linaro.org>
>>> ---
>>>   sound/soc/ux500/ux500_pcm.c | 26 +++++++++++++++++++++-----
>>>   1 file changed, 21 insertions(+), 5 deletions(-)
>>>
>>> diff --git a/sound/soc/ux500/ux500_pcm.c b/sound/soc/ux500/ux500_pcm.c
>>> index 2f1bdb7..00cdd7b 100644
>>> --- a/sound/soc/ux500/ux500_pcm.c
>>> +++ b/sound/soc/ux500/ux500_pcm.c
>>> @@ -134,15 +134,31 @@ static const struct snd_dmaengine_pcm_config ux500_dmaengine_pcm_config = {
>>>   	.prepare_slave_config = ux500_pcm_prepare_slave_config,
>>>   };
>>>
>>> +static const struct snd_dmaengine_pcm_config ux500_dmaengine_of_pcm_config = {
>>> +	.prepare_slave_config = ux500_pcm_prepare_slave_config,
>>> +};
>>> +
>>>   int ux500_pcm_register_platform(struct platform_device *pdev)
>>>   {
>>> +	const struct snd_dmaengine_pcm_config *pcm_config;
>>> +	struct device_node *np = pdev->dev.of_node;
>>> +	unsigned int pcm_flags;
>>>   	int ret;
>>>
>>> -	ret = snd_dmaengine_pcm_register(&pdev->dev,
>>> -			&ux500_dmaengine_pcm_config,
>>> -			SND_DMAENGINE_PCM_FLAG_NO_RESIDUE |
>>> -			SND_DMAENGINE_PCM_FLAG_COMPAT |
>>> -			SND_DMAENGINE_PCM_FLAG_NO_DT);
>>> +	if (np) {
>>> +		pcm_config = &ux500_dmaengine_of_pcm_config;
>>> +
>>> +		pcm_flags = SND_DMAENGINE_PCM_FLAG_NO_RESIDUE |
>>> +			SND_DMAENGINE_PCM_FLAG_COMPAT;
>>> +	} else {
>>> +		pcm_config = &ux500_dmaengine_pcm_config;
>>> +
>>> +		pcm_flags = SND_DMAENGINE_PCM_FLAG_NO_RESIDUE |
>>> +			SND_DMAENGINE_PCM_FLAG_NO_DT |
>>> +			SND_DMAENGINE_PCM_FLAG_COMPAT;
>>> +	}
>>> +
>>> +	ret = snd_dmaengine_pcm_register(&pdev->dev, pcm_config, pcm_flags);
>>>   	if (ret < 0) {
>>>   		dev_err(&pdev->dev,
>>>   			"%s: ERROR: Failed to register platform '%s' (%d)!\n",
>>>
>>
>