Re: [PATCH 4/5] ASoC: SPEAr: remove custom DMA alloc compat function

[Lars-Peter Clausen <lars@metafoo.de>]

On 12/10/2013 09:53 AM, Rajeev kumar wrote:
> On 12/10/2013 1:15 PM, Lars-Peter Clausen wrote:
>> On 12/10/2013 07:30 AM, Rajeev kumar wrote:
>>> On 12/10/2013 2:47 AM, Lars-Peter Clausen wrote:
>>>> On 12/09/2013 09:24 PM, Stephen Warren wrote:
>>>>> From: Stephen Warren<swarren@nvidia.com>
>>>>>
>>>>> spear_pcm_request_chan() is almost identical to
>>>>> dmaengine_pcm_compat_request_channel(), with the exception that the
>>>>> latter:
>>>>>
>>>>> a) Assumes that the DAI DMA data is a struct snd_dmaengine_dai_dma_data
>>>>>      pointer rather than some custom type.
>>>>>
>>>>> b) dma_data->filter_data rather than dma_data should be passed to
>>>>>      snd_dmaengine_pcm_request_channel() as the filter data.
>>>>>
>>>>> Make minor changes to the SPEAr DAI drivers so that those two conditions
>>>>> are met. This allows removal of the custom .compat_request_channel().
>>>>>
>>>>> Signed-off-by: Stephen Warren<swarren@nvidia.com>
>>>>> ---
>>>>>    include/sound/spear_dma.h   |  1 -
>>>>>    sound/soc/spear/spdif_in.c  | 10 +++++++---
>>>>>    sound/soc/spear/spdif_out.c | 10 +++++++---
>>>>>    sound/soc/spear/spear_pcm.c | 21 +++++++--------------
>>>>>    sound/soc/spear/spear_pcm.h |  4 +++-
>>>>>    5 files changed, 24 insertions(+), 22 deletions(-)
>>>>>
>>>>> diff --git a/include/sound/spear_dma.h b/include/sound/spear_dma.h
>>>>> index 1b365bfdfb37..65aca51fe255 100644
>>>>> --- a/include/sound/spear_dma.h
>>>>> +++ b/include/sound/spear_dma.h
>>>>> @@ -29,7 +29,6 @@ struct spear_dma_data {
>>>>>        dma_addr_t addr;
>>>>>        u32 max_burst;
>>>>>        enum dma_slave_buswidth addr_width;
>>>>> -    bool (*filter)(struct dma_chan *chan, void *slave);
>>>>>    };
>>>>
>>>> Hm, that spear_dma_data struct looks pretty much like
>>>> snd_dmaengine_dai_dma_data. It's a bit hard to say how it is used exactly
>>>> since the receiver of that struct doesn't seem to be upstream. Rajeev, how
>>>> is this used? The data in spear_dma_data looks like it should be passed to
>>>> the DMA driver via dmaengine_slave_config() rather than while requesting
>>>> the
>>>> channel.
>>>>
>>>> - Lars
>>>> .
>>>>
>>>
>>> The structure spear_dma_data is used to initialize dma parameters
>>> received from
>>> platform data which is required for dma slave configuration.
>>
>> Those parameters look like they should be configured using
>> dmaengine_slave_config(). And not by passing them to the filter function.
>>
>> - Lars
>>
>> .
>>
> 
> Yes these parameter will be configured through dmaengine_slave_config().

Ok, but this happens in the filter callback? Or is this piece just missing
from the upstream driver at the moment? Do you think the code can be
rewritten to use the generic snd_dmaengine_dai_dma_data struct?

Thanks,
- Lars