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

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



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@xxxxxxxxxxxxxxx>

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 We can back to the review after, you need at least to re-send because this series has been outdated.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.

--
Ben Dooks				http://www.codethink.co.uk/
Senior Engineer				Codethink - Providing Genius

https://www.codethink.co.uk/privacy.html



[Index of Archives]     [ARM Kernel]     [Linux ARM]     [Linux ARM MSM]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux