Re: [RFC PATCH 4/5] iio: accel: Support Kionix/ROHM KX022A accelerometer

[Matti Vaittinen]

Hi Andy,

On 9/28/22 17:06, Andy Shevchenko wrote:
> On Wed, Sep 28, 2022 at 02:14:14PM +0300, Matti Vaittinen wrote:
> > On 9/22/22 20:03, Jonathan Cameron wrote:
> > > On Wed, 21 Sep 2022 14:45:35 +0300
>
> ...
>
> > > > +		dev_err(dev, "no regmap\n");
> > >
> > > Use dev_err_probe() for all dev_err() stuff in probe paths.
> > > It ends up cleaner and we don't care about the tiny overhead
> > > of checking for deferred.
> >
> > This one bothers me a bit. It just does not feel correct to pass -EINVAL for
> > the dev_err_probe() so the dev_err_probe() can check if -EINVAL !=
> > -EPROBE_DEFER. I do understand perfectly well the consistent use of
> > dev_err_probe() for all cases where we get an error-code from a function and
> > return it - but using dev_err_probe() when we hard-code the return value in
> > code calling the dev_err_probe() does not feel like "the right thing to do"
> > (tm).
> >
> > Eg, I agree that
> > return dev_err_probe(dev, ret, "bar");
> > is nice even if we know the function that gave us the "ret" never requests
> > defer (as that can change some day).
> >
> > However, I don't like issuing:
> > return dev_err_probe(dev, -EINVAL, "bar");
>
> This case specifically was added into documentation by 7065f92255bb ("driver
> core: Clarify that dev_err_probe() is OK even w/out -EPROBE_DEFER").

Yes. And this is exactly what I meant with:
>> Eg, I agree that
>> return dev_err_probe(dev, ret, "bar");
>> is nice even if we know the function that gave us the "ret" never 
requests
>> defer

There is still (in my opinion) a significant difference if we call:
>> return dev_err_probe(dev, -EINVAL, "bar");

- where we really hard-code the -EINVAL as a parameter to the 
dev_err_probe()

> > Well, please let me know if you think the dev_err_probe() should be used
> > even in cases where we hard code the return to something...
>
> And this should be, of course, maintainer's decision.

Ultimately, yes.

Best Regards
	--Matti

--
Matti Vaittinen
Linux kernel developer at ROHM Semiconductors
Oulu Finland

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