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Date:   Wed, 28 Jul 2021 16:37:59 +0530
From:   Vinod Koul <vkoul@kernel.org>
To:     Marek Vasut <marex@denx.de>
Cc:     dmaengine@vger.kernel.org, Akinobu Mita <akinobu.mita@gmail.com>,
        Kedareswara rao Appana <appana.durga.rao@xilinx.com>,
        Michal Simek <monstr@monstr.eu>,
        Vinod Koul <vinod.koul@intel.com>
Subject: Re: [PATCH] dmaengine: xilinx: Add empty device_config function
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On 17-07-21, 16:48, Marek Vasut wrote:
> On 7/17/21 4:34 PM, Vinod Koul wrote:
> > On 17-07-21, 14:01, Marek Vasut wrote:
> > > On 7/17/21 1:36 PM, Vinod Koul wrote:
> > > > On 16-07-21, 20:22, Marek Vasut wrote:
> > > > > Various DMA users call the dmaengine_slave_config() and expect it to
> > > > > succeed, but that can only succeed if .device_config is implemented.
> > > > > Add empty device_config function rather than patching all the places
> > > > > which use dmaengine_slave_config().
> > > > 
> > > > .device_config is optional, Yes the dmaengine_slave_config() will check
> > > > and return error...
> > > > 
> > > > I think it would make sense to handle this in caller... (ignore
> > > > ENOSYS..) rather than add a dummy one
> > > 
> > > That's what I was trying to avoid -- patching all the places in kernel which
> > > might fail. Why handle it in caller ?
> > 
> > And how many places would that be..? The xilinx driver using xilinx
> > dma right>
> 
> git grep indicates around 170 matches on dmaengine_slave_config. In my case,
> it is generic PCM DMA in sound/soc/soc-generic-dmaengine-pcm.c .

Okay lets have this. Looks like kbuild-bot is not happy, can you fix
that and send update

-- 
~Vinod