linux-kernel - Re: [PATCH] drm/panfrost: Fix regulator_get

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Message-ID: <CAL_JsqKWEe=+X5AYRJ-_8peTzfrOrRBfFWgk8c6h3TN6f0ZHtA@mail.gmail.com>
Date:   Mon, 9 Sep 2019 16:41:32 +0100
From:   Rob Herring <robh@...nel.org>
To:     Steven Price <steven.price@....com>
Cc:     Mark Brown <broonie@...nel.org>,
        Tomeu Vizoso <tomeu.vizoso@...labora.com>,
        David Airlie <airlied@...ux.ie>,
        Daniel Vetter <daniel@...ll.ch>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        dri-devel <dri-devel@...ts.freedesktop.org>
Subject: Re: [PATCH] drm/panfrost: Fix regulator_get_optional() misuse

On Fri, Sep 6, 2019 at 4:23 PM Steven Price <steven.price@....com> wrote:
>
> On 04/09/2019 13:30, Mark Brown wrote:
> > The panfrost driver requests a supply using regulator_get_optional()
> > but both the name of the supply and the usage pattern suggest that it is
> > being used for the main power for the device and is not at all optional
> > for the device for function, there is no meaningful handling for absent
> > supplies.  Such regulators should use the vanilla regulator_get()
> > interface, it will ensure that even if a supply is not described in the
> > system integration one will be provided in software.
> >
> > Signed-off-by: Mark Brown <broonie@...nel.org>
>
> Tested-by: Steven Price <steven.price@....com>
>
> Looks like my approach to this was wrong - so we should also revert the
> changes I made previously.
>
> ----8<----
> From fe20f8abcde8444bb41a8f72fb35de943a27ec5c Mon Sep 17 00:00:00 2001
> From: Steven Price <steven.price@....com>
> Date: Fri, 6 Sep 2019 15:20:53 +0100
> Subject: [PATCH] drm/panfrost: Revert changes to cope with NULL regulator
>
> Handling a NULL return from devm_regulator_get_optional() doesn't seem
> like the correct way of handling this. Instead revert the changes in
> favour of switching to using devm_regulator_get() which will return a
> dummy regulator instead.
>
> Reverts commit 52282163dfa6 ("drm/panfrost: Add missing check for pfdev->regulator")
> Reverts commit e21dd290881b ("drm/panfrost: Enable devfreq to work without regulator")

Does a straight revert of these 2 patches not work? If it does work,
can you do that and send to the list. I don't want my hand slapped
again reverting things.

Rob