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Date:   Thu, 26 Sep 2019 10:18:01 -0700
From:   Vinod Koul <vkoul@kernel.org>
To:     Radhey Shyam Pandey <radheys@xilinx.com>
Cc:     "dan.j.williams@intel.com" <dan.j.williams@intel.com>,
        Michal Simek <michals@xilinx.com>,
        "nick.graumann@gmail.com" <nick.graumann@gmail.com>,
        "andrea.merello@gmail.com" <andrea.merello@gmail.com>,
        Appana Durga Kedareswara Rao <appanad@xilinx.com>,
        "mcgrof@kernel.org" <mcgrof@kernel.org>,
        "dmaengine@vger.kernel.org" <dmaengine@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH -next 3/8] dmaengine: xilinx_dma: Introduce
 xilinx_dma_get_residue
Message-ID: <20190926171801.GM3824@vkoul-mobl>
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On 26-09-19, 05:52, Radhey Shyam Pandey wrote:

> > > +	 * VDMA and simple mode do not support residue reporting, so the
> > > +	 * residue field will always be 0.
> > > +	 */
> > > +	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA ||
> > !chan->has_sg)
> > > +		return residue;
> > 
> > why not check this in status callback?
> Assuming we mean to move vdma and non-sg check to xilinx_dma_tx_status.
> Just a thought- Keeping this check in xilinx_dma_get_residue provides
> an abstraction and caller can simply call this func with knowing about
> IP config specific residue calculation. Considering this point does it
> looks ok ? 

well you are checking either way, so calling the lower level function
only when you need it makes more sense!

-- 
~Vinod