On 05/30/2013 08:46 PM, Lars-Peter Clausen wrote:
>>> +static int jz4740_dma_alloc_chan_resources(struct dma_chan *c)
>>> +{
>>> + struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
>>> +
>>> + chan->jz_chan = jz4740_dma_request(chan, NULL);
>>> + if (!chan->jz_chan)
>>> + return -EBUSY;
>>> +
>>> + jz4740_dma_set_complete_cb(chan->jz_chan, jz4740_dma_complete_cb);
>>> +
>>> + return 0;
>> Sorry, I didnt reply on this one. The API expects you to allocate a pool of
>> descriptors. These descriptors are to be used in .device_prep_xxx calls
>> later.
>
> The size of the descriptor is not fixed, so they can not be pre-allocated. And
> this is nothing new either, most of the more recently added dmaengine drivers
> allocate their descriptors on demand.
Vinod, are you ok with this explanation?
- Lars
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