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

[Bjorn Andersson]

On Thu, Jun 15, 2023 at 11:26:13PM +0200, Krzysztof Kozlowski wrote:
> 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@xxxxxxxxxx>
> 
> 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.
> 

I agree, the mmio regmap interface should only fail because of bugs or
things are misconfigured. Would be nice to capture that in a WARN_ON()
or something...

Regards,
Bjorn