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Date:   Mon, 23 Nov 2020 12:22:56 +0200
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     Sia Jee Heng <jee.heng.sia@intel.com>
Cc:     vkoul@kernel.org, Eugeniy.Paltsev@synopsys.com, robh+dt@kernel.org,
        dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org,
        devicetree@vger.kernel.org
Subject: Re: [PATCH v5 16/16] dmaengine: dw-axi-dmac: Virtually split the
 linked-list
Message-ID: <20201123102256.GV4077@smile.fi.intel.com>
References: <20201123023452.7894-1-jee.heng.sia@intel.com>
 <20201123023452.7894-17-jee.heng.sia@intel.com>
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On Mon, Nov 23, 2020 at 10:34:52AM +0800, Sia Jee Heng wrote:
> AxiDMA driver exposed the dma_set_max_seg_size() to the DMAENGINE.
> It shall helps the DMA clients to create size-optimized linked-list
> for the controller.
> 
> However, there are certain situations where DMA client might not be
> abled to benefit from the dma_get_max_seg_size() if the segment size
> can't meet the nature of the DMA client's operation.
> 
> In the case of ALSA operation, ALSA application and driver expecting
> to run in a period of larger than 10ms regardless of the bit depth.
> With this large period, there is a strong request to split the linked-list
> in the AxiDMA driver.

I'm wondering why ASoC generic code can't use DMA channel and device
capabilities and prepare SG list with all limitations taken into account.


-- 
With Best Regards,
Andy Shevchenko