Subject: [PATCH v2 09/11] dma: mmp_pdma: implement DMA_PAUSE and DMA_RESUME

From: [email-masked] (Daniel Mack)
Date: Wed, 14 Aug 2013 11:02:06 +0200

On 14.08.2013 10:15, Vinod Koul wrote:
> On Sat, Aug 10, 2013 at 06:52:23PM +0200, Daniel Mack wrote:
>> This is needed at least for audio operation.
>>
>> Signed-off-by: Daniel Mack <[email-masked]>
>> ---
>>  drivers/dma/mmp_pdma.c | 6 ++++++
>>  1 file changed, 6 insertions(+)
>>
>> diff --git a/drivers/dma/mmp_pdma.c b/drivers/dma/mmp_pdma.c
>> index 579f79a..7a0956b 100644
>> --- a/drivers/dma/mmp_pdma.c
>> +++ b/drivers/dma/mmp_pdma.c
>> @@ -659,6 +659,12 @@ static int mmp_pdma_control(struct dma_chan *dchan, enum dma_ctrl_cmd cmd,
>>  		if (cfg->slave_id)
>>  			chan->drcmr = cfg->slave_id;
>>  		break;
>> +	case DMA_PAUSE:
>> +		disable_chan(chan->phy);
>> +		break;
>> +	case DMA_RESUME:
>> +		start_pending_queue(chan);
> This is your usual start_pending ops. The meaning of pause and resume is NOT to
> drop current descriptor and start from next one. You need to start from where
> you had left off.
> 
> The way I see in this driver you are going to pick next descriptor and since
> usage is audio, imply loss of audio in puase-resume case.
> 
> You need to resume here, not start next one

Ah, ok. Thanks for the review. Can you just omit that one and take the
rest of the patches? Pause and resume is something I can take care of in
a separate patch then, and it should hold off the other changes IMO.

Thanks,
Daniel