From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peng Fan <peng.fan@nxp.com>
Date: Fri, 31 May 2019 08:23:23 +0000
Subject: [U-Boot] [PATCH] regulator: Allow autosetting fixed regulators
In-Reply-To: <EF34CBF3-67DE-4FC4-8B75-56786A106F52@svenschwermer.de>
References: <20190531072729.16487-1-sven@svenschwermer.de>
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 <EF34CBF3-67DE-4FC4-8B75-56786A106F52@svenschwermer.de>
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> Subject: Re: [PATCH] regulator: Allow autosetting fixed regulators
> 
> Hi Peng,
> 
> > According to code:
> >        if (uc_pdata->flags & REGULATOR_FLAG_AUTOSET_UV)
> >                ret = regulator_set_value(dev, uc_pdata->min_uV);
> >        if (!ret && (uc_pdata->flags & REGULATOR_FLAG_AUTOSET_UA))
> >                ret = regulator_set_current(dev, uc_pdata->min_uA);
> >
> > So you get -ENOSYS from the upper code?
> 
> Yes, for fixed regulators, the following if clause evaluates to true in
> regulator_pre_probe:
> 
> 	/* Those values are optional (-ENODATA if unset) */
> 	if ((uc_pdata->min_uV != -ENODATA) &&
> 	    (uc_pdata->max_uV != -ENODATA) &&
> 	    (uc_pdata->min_uV == uc_pdata->max_uV))
> 		uc_pdata->flags |= REGULATOR_FLAG_AUTOSET_UV;

For fixed regulator, will min_uV/max_uV be set to value other
than -ENODATA? I think no.

Regards,
Peng.

> 
> However, in regulator_set_value, there is this section:
> 
> 	if (!ops || !ops->set_value)
> 		return -ENOSYS;
> 
> So for fixed regulators, which don’t have a set_value, we’ll always get a
> -ENOSYS.
> 
> Sven