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Subject: Re: DMA Engine: Transfer From Userspace
To:     Federico Vaga <federico.vaga@cern.ch>,
        Vinod Koul <vkoul@kernel.org>,
        Dan Williams <dan.j.williams@intel.com>
Cc:     dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org
References: <5614531.lOV4Wx5bFT@harkonnen>
From:   Dave Jiang <dave.jiang@intel.com>
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Date:   Fri, 19 Jun 2020 16:31:24 -0700
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On 6/19/2020 3:47 PM, Federico Vaga wrote:
> Hello,
> 
> is there the possibility of using a DMA engine channel from userspace?
> 
> Something like:
> - configure DMA using ioctl() (or whatever configuration mechanism)
> - read() or write() to trigger the transfer
> 

I may have supposedly promised Vinod to look into possibly providing something 
like this in the future. But I have not gotten around to do that yet. Currently, 
no such support.