Date:   Wed, 1 Feb 2023 09:33:32 +0100
From:   Miquel Raynal <miquel.raynal@bootlin.com>
To:     Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc:     Arnd Bergmann <arnd@kernel.org>,
        Alexander Aring <alex.aring@gmail.com>,
        Stefan Schmidt <stefan@datenfreihafen.org>,
        Arnd Bergmann <arnd@arndb.de>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>, linux-kernel@vger.kernel.org,
        linux-wpan@vger.kernel.org, netdev@vger.kernel.org
Subject: Re: [PATCH] [v2] at86rf230: convert to gpio descriptors
Message-ID: <20230201093332.15b0ff9a@xps-13>
In-Reply-To: <CAKdAkRSuDJgdsSQqy9Cc_eUYuOfFsLmBJ8Rd93uQhY6HV8nN4w@mail.gmail.com>
References: <20230126162323.2986682-1-arnd@kernel.org>
        <CAKdAkRQT_Jk5yBeMZqh=M1JscVLFieZTQjLGOGxy8nHh8SnD3A@mail.gmail.com>
        <CAKdAkRSuDJgdsSQqy9Cc_eUYuOfFsLmBJ8Rd93uQhY6HV8nN4w@mail.gmail.com>
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Hi Dmitry,

dmitry.torokhov@gmail.com wrote on Tue, 31 Jan 2023 16:50:07 -0800:

> On Tue, Jan 31, 2023 at 3:52 PM Dmitry Torokhov
> <dmitry.torokhov@gmail.com> wrote:
> >
> > Hi Arnd,
> >
> > On Thu, Jan 26, 2023 at 8:32 AM Arnd Bergmann <arnd@kernel.org> wrote: =
=20
> > >
> > >         /* Reset */
> > > -       if (gpio_is_valid(rstn)) {
> > > +       if (rstn) {
> > >                 udelay(1);
> > > -               gpio_set_value_cansleep(rstn, 0);
> > > +               gpiod_set_value_cansleep(rstn, 0);
> > >                 udelay(1);
> > > -               gpio_set_value_cansleep(rstn, 1);
> > > +               gpiod_set_value_cansleep(rstn, 1); =20
> >
> > For gpiod conversions, if we are not willing to chase whether existing
> > DTSes specify polarities
> > properly and create workarounds in case they are wrong, we should use
> > gpiod_set_raw_value*()
> > (my preference would be to do the work and not use "raw" variants).
> >
> > In this particular case, arch/arm/boot/dts/vf610-zii-dev-rev-c.dts
> > defines reset line as active low,
> > so you are leaving the device in reset state.

You mean the semantics of gpio_set_value() gpiod_set_value() are
different? Looking at your patch it looks like gpio_set_value() asserts
a physical line state (high or low) while gpiod_set_value() would
actually try to assert a logical state (enabled or disabled) with the
meaning of those being possibly inverted thanks to the DT polarities.
Am I getting this right?

> > Please review your other conversion patches. =20
>=20
> We also can not change the names of requested GPIOs from "reset-gpio"
> to "rstn-gpios" and expect
> this to work.

Yep, missed that indeed.

>=20
> Stefan, please consider reverting this and applying a couple of
> patches I will send out shortly.

If my above understanding is right, then, yeah, the current
patches need to be fixed.

Thanks,
Miqu=C3=A8l