Re: [PATCH] regulator: pwm: Don't warn on probe deferral

[Uwe Kleine-König]

On Mon, Feb 24, 2020 at 04:58:59PM +0000, Mark Brown wrote:
> On Mon, Feb 24, 2020 at 02:40:48PM +0000, Jon Hunter wrote:
> > Deferred probe is an expected return value for devm_pwm_get(). Given
> > that the driver deals with it properly, there's no need to output a
> > warning that may potentially confuse users.
> 
> >  		ret = PTR_ERR(drvdata->pwm);
> > -		dev_err(&pdev->dev, "Failed to get PWM: %d\n", ret);
> > +		if (ret != -EPROBE_DEFER)
> > +			dev_err(&pdev->dev, "Failed to get PWM: %d\n", ret);
> 
> This then means that there's no way for users to determine why the
> driver has failed to instantiate which can be frustrating.  It'd be
> better to at least have some dev_dbg() output when deferring so that
> there's something for people to go on without having to instrument the
> code.

Not printing an error message is quite usual however. I think a generic
approach that for example makes the list of devices that should be
retried to probe on the next opportunity inspectable would be nice.

Best regards
Uwe

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