[4/6] dma: tegra: add accurate reporting of dma state

[Dmitry Osipenko <digetx@gmail.com>]

22.02.2019 21:10, Dmitry Osipenko пишет:
> 22.02.2019 20:23, Ben Dooks пишет:
>> On 21/02/2019 13:02, Dmitry Osipenko wrote:
>>> 21.02.2019 13:06, Ben Dooks пишет:
>>>> On 21/02/2019 00:41, Dmitry Osipenko wrote:
>>>>> 31.10.2018 19:03, Ben Dooks пишет:
>>>>>> The tx_status callback does not report the state of the transfer
>>>>>> beyond complete segments. This causes problems with users such as
>>>>>> ALSA when applications want to know accurately how much data has
>>>>>> been moved.
>>>>>>
>>>>>> This patch addes a function tegra_dma_update_residual() to query
>>>>>> the hardware and modify the residual information accordinly. It
>>>>>> takes into account any hardware issues when trying to read the
>>>>>> state, such as delays between finishing a buffer and signalling
>>>>>> the interrupt.
>>>>>>
>>>>>> Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
>>>>>
>>>>> Hello Ben,
>>>>>
>>>>> Do you have any plans to submit a new version of this patch? It's really useful and fixes a real problem with the audio playback. I could help with finalizing the patch and could submit it for you if you happened to lost the interest.
>>>>
>>>> Personally I think the original version was fine. It has been tested
>>>> and returns fairly quickly (I am not a fan of just adding more delay in)
>>>>
>>>> My notes say the condition doesn't last for long and the loop tends
>>>> to terminate within 2 runs.
>>>>
>>>
>>> Okay, so are you going to re-send the patch? We can back to the review after, you need at least to re-send because this series has been outdated. Also please take a look and feel free to use as-is the reduced variant of yours patch that I was carrying and testing for months now [0], it works great.
>>>
>>> [0] https://github.com/grate-driver/linux/commit/ab8a67a6f47185f265f16749b55df214aaaefad4
>>>
>>
>> I can try rebasing, but I have not got a lot of time to do any testing
>> at the moment. I agree I should have remembered to chase this stuff up
>> earlier.
> 
> No problems, thank you. I'll help with the testing. And I could rebase the patch and send it out for you if will be needed, please just let me know if you're okay with it.
> 

Hello Ben,

Do you have any status update on the state of the patch? Again, I could help with sending it out for you if you're too busy or something else. Please let me know how we could proceed with getting the fix upstreamed and sorry for disturbing you again with this.