linux-kernel - Re: [PATCH] soc: qcom: icc-bwmon: Don't ignore return values of regmap functions

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Date:   Thu, 15 Jun 2023 23:26:13 +0200
From:   Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>
To:     Konrad Dybcio <konrad.dybcio@...aro.org>,
        Andy Gross <agross@...nel.org>,
        Bjorn Andersson <andersson@...nel.org>
Cc:     Marijn Suijten <marijn.suijten@...ainline.org>,
        linux-arm-msm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] soc: qcom: icc-bwmon: Don't ignore return values of
 regmap functions

On 15/06/2023 23:12, Konrad Dybcio wrote:
> As it turns out, not all regmap accesses succeed. Not knowing this is
> particularly suboptimal when there's a breaking change to the regmap
> APIs. Monitor the return values of regmap_ calls and propagate errors,
> should any occur.
> 
> To keep any level of readability in bwmon_enable(), add some comments
> to separate the logical blocks.
> 
> Signed-off-by: Konrad Dybcio <konrad.dybcio@...aro.org>

Nice coincidence, I just had some talks with a friend about uselessness
(IMHO) of regmap MMIO return status checks.

Sorry, for me most of this makes the code difficult to read for no gain.
Errors are not real. This is some artificial problem. Solving it makes
code less maintainable.

If we used here readl/writel, you would not add any checks, right? Then
don't add for regmap mmio.

Best regards,
Krzysztof