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From:   Baolin Wang <baolin.wang@linaro.org>
Date:   Wed, 18 Apr 2018 13:40:54 +0800
Message-ID: <CAMz4ku+zPiucHyLF5HBtH9LhcTDUUec-kTLQG2YQ3hBK=9HHDw@mail.gmail.com>
Subject: Re: [PATCH 5/5] dmaengine: sprd: Add 'device_config' and
 'device_prep_slave_sg' interfaces
To:     Lars-Peter Clausen <lars@metafoo.de>
Cc:     Dan Williams <dan.j.williams@intel.com>,
        Vinod Koul <vinod.koul@intel.com>,
        Eric Long <eric.long@spreadtrum.com>,
        Mark Brown <broonie@kernel.org>, dmaengine@vger.kernel.org,
        LKML <linux-kernel@vger.kernel.org>
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On 17 April 2018 at 18:45, Lars-Peter Clausen <lars@metafoo.de> wrote:
> On 04/10/2018 09:46 AM, Baolin Wang wrote:
> [...]
>> +static int sprd_dma_slave_config(struct dma_chan *chan,
>> +                              struct dma_slave_config *config)
>> +{
>> +     struct sprd_dma_chn *schan = to_sprd_dma_chan(chan);
>> +     struct sprd_dma_config *slave_cfg =
>> +             container_of(config, struct sprd_dma_config, config);
>> +
>
> Please do not overload standard API with custom semantics. This makes the
> driver incompatible to the API and negates the whole idea of having a common
> API. E.g. this will crash when somebody passes a normal dma_slave_config
> struct to this function.
>

Yes, we have discussed with Vinod how to use 'dma_slave_config' to
reach our requirements. Thanks for your comments.

-- 
Baolin.wang
Best Regards