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Subject: Re: [PATCH v6 12/16] dmaengine: tegra-apb: Clean up suspend-resume
To:     Dmitry Osipenko <digetx@gmail.com>,
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From:   Jon Hunter <jonathanh@nvidia.com>
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Date:   Thu, 30 Jan 2020 14:09:41 +0000
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On 30/01/2020 04:38, Dmitry Osipenko wrote:
> It is enough to check whether hardware is busy on suspend and to reset
> it across of suspend-resume because channel's configuration is fully
> re-programmed on each DMA transaction anyways and because save-restore
> of an active channel won't end up well without pausing transfer prior to
> saving of the state (note that all channels shall be idling at the time of
> suspend, so save-restore is not needed at all).

I guess if we ever wanted to support SNDRV_PCM_INFO_PAUSE for audio and
support the pause callback, then saving and restoring the channels could
be needed. Right now I believe that it will just terminate_all transfers
for audio on entering suspend. Any value in keeping this?

Jon

-- 
nvpublic