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Date:   Wed, 16 Jun 2021 17:32:36 +0530
From:   Vinod Koul <vkoul@kernel.org>
To:     Mark Brown <broonie@kernel.org>
Cc:     Bjorn Andersson <bjorn.andersson@linaro.org>,
        Wolfram Sang <wsa@kernel.org>, linux-arm-msm@vger.kernel.org,
        Andy Gross <agross@kernel.org>,
        Matthias Kaehlcke <mka@chromium.org>,
        Douglas Anderson <dianders@chromium.org>,
        Sumit Semwal <sumit.semwal@linaro.org>,
        Amit Pundir <amit.pundir@linaro.org>,
        linux-spi@vger.kernel.org, linux-i2c@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 4/7] spi: spi-geni-qcom: Add support for GPI dma
Message-ID: <YMnoXKAvL0461GRR@vkoul-mobl>
References: <20210111151651.1616813-1-vkoul@kernel.org>
 <20210111151651.1616813-5-vkoul@kernel.org>
 <20210111163504.GD4728@sirena.org.uk>
 <YMm7ZWXnJyb8QT1u@vkoul-mobl>
 <20210616113505.GB6418@sirena.org.uk>
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On 16-06-21, 12:35, Mark Brown wrote:
> On Wed, Jun 16, 2021 at 02:20:45PM +0530, Vinod Koul wrote:
> 
> > Looking at the code, that is ideal case. Only issue I can see is that
> > core DMA mapping device being used is incorrect. The core would use
> > ctlr->dev.parent which is the spi0 device here.
> 
> Why would the parent of the controller be a SPI device?

Sorry my bad, I meant the core use ctlr->dev.parent which in this case is
the SPI master device, 880000.spi

> > But in this case, that wont work. We have a parent qup device which is
> > the parent for both spi and dma device and needs to be used for
> > dma-mapping! 
> 
> > If we allow drivers to set dma mapping device and use that, then I can
> > reuse the core. Let me know if that is agreeable to you and I can hack
> > this up. Maybe add a new member in spi_controller which is filled by
> > drivers in can_dma() callback?
> 
> Possibly, I'd need to see the code.

Ok, let me do a prototype and share ...

Thanks
-- 
~Vinod