Re: [PATCH] regulator: max14577: Fix invalid return value on DT parse success

[Krzysztof Kozlowski <k.kozlowski@samsung.com>]

On Fri, 2014-02-21 at 16:25 +0530, Sachin Kamat wrote:
> On 21 February 2014 16:12, Krzysztof Kozlowski <k.kozlowski@samsung.com> wrote:
> > On Fri, 2014-02-21 at 15:54 +0530, Sachin Kamat wrote:
> >> Hi Krzysztof,
> >>
> >> On 20 February 2014 20:49, Krzysztof Kozlowski <k.kozlowski@samsung.com> wrote:
> >> > This fixes bug introduced in 667a6b7a (regulator: max14577: Add missing
> >> > of_node_put). The DTS parsing function returned number of matched
> >> > regulators as success status which then was compared against 0 in probe.
> >> >
> >> > Result was a probe fail after successful parsing the DTS:
> >> > max14577-regulator: probe of max14577-regulator failed with error 2
> >> >
> >> > Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> >> > ---
> >> >  drivers/regulator/max14577.c |    4 +++-
> >> >  1 file changed, 3 insertions(+), 1 deletion(-)
> >> >
> >> > diff --git a/drivers/regulator/max14577.c b/drivers/regulator/max14577.c
> >> > index 186df8785a91..6ba11a8dd23d 100644
> >> > --- a/drivers/regulator/max14577.c
> >> > +++ b/drivers/regulator/max14577.c
> >> > @@ -168,11 +168,13 @@ static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev)
> >> >                         MAX14577_REG_MAX);
> >> >         if (ret < 0) {
> >> >                 dev_err(&pdev->dev, "Error parsing regulator init data: %d\n", ret);
> >> > +               of_node_put(np);
> >> > +               return ret;
> >> >         }
> >> >
> >> >         of_node_put(np);
> >> >
> >> > -       return ret;
> >> > +       return 0;
> >> >  }
> >>
> >> Instead of so many changes here, you could simply make the following change
> >> in the max14577_regulator_probe function.
> >>
> >> ret = max14577_regulator_dt_parse_pdata(pdev);
> >> if (ret < 0)
> >>         return ret;
> >
> > That still wouldn't be sufficient because later in probe() the 'ret' is
> > not reassigned (if devm_regulator_register succeeds) and it is directly
> > returned at the probe() end. So still the number of matched regulators
> > would be returned as probe result.
> 
> Ah, you are right. In that case how about the following:
> 
> -  if (ret < 0) {
> + if (ret < 0)
>       dev_err(&pdev->dev, "Error parsing regulator init data: %d\n", ret);
> -  }
> + else
> +      ret = 0;
> 
> I am just trying to see if we can avoid any code duplication.

Looks good. Thanks for idea, I'll send v2.

Best regards,
Krzysztof