Re: [PATCH] driver: base: pinctrl: return error from pinctrl_bind_pins()

[Deepak Das]

On Tuesday 13 September 2016 05:29 PM, Linus Walleij wrote:
> On Tue, Sep 13, 2016 at 9:13 AM, Deepak <deepak_das@xxxxxxxxxx> wrote:
>
> > strict pin controller returns -EINVAL in case of pin request which
> > is already claimed by somebody else.
> > Following is the sequence of calling pin_request() from
> > pinctrl_bind_pins():-
> > pinctrl_bind_pins()->pinctrl_select_state()->pinmux_enable_setting()->
> > pin_request()
> >
> > But pinctrl_bind_pins() only returns -EPROBE_DEFER which makes device
> > driver probe successful even if the pin request is rejected by the pin
> > controller subsystem.
> >
> > This commit modifies pinctrl_bind_pins() to return error if the pin is
> > rejected by pin control subsystem.
> >
> > Signed-off-by: Deepak Das <deepak_das@xxxxxxxxxx>
>
> Aha
>
> >       /* Only return deferrals */
> > -    if (ret != -EPROBE_DEFER)
> > +    if ((ret != -EPROBE_DEFER) && (ret != -EINVAL))
> >           ret = 0;
>
> I rewrote this when applying, like this:
>
> -       /* Only return deferrals */
> -       if (ret != -EPROBE_DEFER)
> -               ret = 0;
> +       /* Return deferrals */
> +       if (ret == -EPROBE_DEFER)
> +               return ret;
> +       if (ret == -EINVAL) {
> +               dev_err(dev, "could not initialize pin control state\n");
> +               return ret;
> +       }
> +       /* We ignore errors like -ENOENT meaning no pinctrl state */
>
> -       return ret;
> +       return 0;
>
> Can you confim that this works for you too?

Yes, This works for me as well but do we really need this extra error 
message ?
error message is printed before returning -EINVAL from most places, 
Although I did not checked all places. For example, error message in 
pin_request():-
dev_err(pctldev->dev, "pin %s already requested by %s; cannot claim for 
%s\n", desc->name, desc->mux_owner, owner);

Thanks,
Deepak Das
> Yours,
> Linus Walleij