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Date:   Tue, 23 Jan 2018 14:49:05 +0530
From:   Vinod Koul <vinod.koul@intel.com>
To:     Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Cc:     Andy Gross <andy.gross@linaro.org>, dmaengine@vger.kernel.org,
        Rob Herring <robh+dt@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        David Brown <david.brown@linaro.org>,
        Dan Williams <dan.j.williams@intel.com>,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-msm@vger.kernel.org, linux-soc@vger.kernel.org,
        yanhe@quicinc.com, ramkri@qti.qualcomm.com, sdharia@quicinc.com
Subject: Re: [PATCH 1/4] dmaengine: qcom: bam_dma: make bam clk optional
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References: <20180116190236.14558-1-srinivas.kandagatla@linaro.org>
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 <20180119055221.GV18649@localhost>
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On Mon, Jan 22, 2018 at 09:55:01AM +0000, Srinivas Kandagatla wrote:

> >>@@ -1180,13 +1180,14 @@ static int bam_dma_probe(struct platform_device *pdev)
> >>  						"qcom,controlled-remotely");
> >>  	bdev->bamclk = devm_clk_get(bdev->dev, "bam_clk");
> >
> >but you still do clk_get unconditionally?
> 
> Only reason to do this way is to not break existing users in the mainline.
> 
> remotely controlled BAM is already supported in upstream driver, there are
> users of this who pass clk from device tree, If I make this conditional then
> subsequent reads to the BAM registers for those instances might crash the
> system.

But these instances are remote controlled, so if we stop representing them
in Linux, why would we read them?

-- 
~Vinod