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Subject: Re: [PATCH v4 02/14] dmaengine: tegra-apb: Implement synchronization
 callback
To:     Dmitry Osipenko <digetx@gmail.com>,
        Laxman Dewangan <ldewangan@nvidia.com>,
        Vinod Koul <vkoul@kernel.org>,
        Dan Williams <dan.j.williams@intel.com>,
        Thierry Reding <thierry.reding@gmail.com>,
        =?UTF-8?B?TWljaGHFgiBNaXJvc8WCYXc=?= <mirq-linux@rere.qmqm.pl>
CC:     <dmaengine@vger.kernel.org>, <linux-tegra@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
References: <20200112173006.29863-1-digetx@gmail.com>
 <20200112173006.29863-3-digetx@gmail.com>
From:   Jon Hunter <jonathanh@nvidia.com>
Message-ID: <c225399c-f032-8001-e67b-b807dcda748c@nvidia.com>
Date:   Tue, 14 Jan 2020 15:15:01 +0000
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On 12/01/2020 17:29, Dmitry Osipenko wrote:
> The ISR tasklet could be kept scheduled after DMA transfer termination,
> let's add synchronization callback which blocks until tasklet is finished.
> 
> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
> ---
>  drivers/dma/tegra20-apb-dma.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c
> index 319f31d27014..664e9c5df3ba 100644
> --- a/drivers/dma/tegra20-apb-dma.c
> +++ b/drivers/dma/tegra20-apb-dma.c
> @@ -798,6 +798,13 @@ static int tegra_dma_terminate_all(struct dma_chan *dc)
>  	return 0;
>  }
>  
> +static void tegra_dma_synchronize(struct dma_chan *dc)
> +{
> +	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
> +
> +	tasklet_kill(&tdc->tasklet);
> +}
> +

Wouldn't there need to be some clean-up here? If the tasklet is
scheduled, seems that there would be some other house-keeping that needs
to be done after killing it.

Jon

-- 
nvpublic