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References: <20230127001141.407071-1-saravanak@google.com> <20230127001141.407071-5-saravanak@google.com>
 <Y9OY6pMwYtab1Avd@smile.fi.intel.com>
In-Reply-To: <Y9OY6pMwYtab1Avd@smile.fi.intel.com>
From:   Saravana Kannan <saravanak@google.com>
Date:   Fri, 27 Jan 2023 23:33:38 -0800
Message-ID: <CAGETcx_sm5Efy=80kc9gNTaZgvOQzBGxwWA1n+bPJYWg43OebA@mail.gmail.com>
Subject: Re: [PATCH v2 04/11] gpiolib: Clear the gpio_device's fwnode
 initialized flag before adding
To:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Sudeep Holla <sudeep.holla@arm.com>,
        Cristian Marussi <cristian.marussi@arm.com>,
        Linus Walleij <linus.walleij@linaro.org>,
        Bartosz Golaszewski <brgl@bgdev.pl>,
        Thomas Gleixner <tglx@linutronix.de>,
        Marc Zyngier <maz@kernel.org>, Shawn Guo <shawnguo@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        Fabio Estevam <festevam@gmail.com>,
        NXP Linux Team <linux-imx@nxp.com>,
        Rob Herring <robh+dt@kernel.org>,
        Frank Rowand <frowand.list@gmail.com>,
        Geert Uytterhoeven <geert+renesas@glider.be>,
        Magnus Damm <magnus.damm@gmail.com>,
        Len Brown <lenb@kernel.org>,
        Daniel Scally <djrscally@gmail.com>,
        Heikki Krogerus <heikki.krogerus@linux.intel.com>,
        Sakari Ailus <sakari.ailus@linux.intel.com>,
        Tony Lindgren <tony@atomide.com>,
        Linux Kernel Functional Testing <lkft@linaro.org>,
        Naresh Kamboju <naresh.kamboju@linaro.org>,
        Abel Vesa <abel.vesa@linaro.org>,
        Alexander Stein <alexander.stein@ew.tq-group.com>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        John Stultz <jstultz@google.com>,
        Doug Anderson <dianders@chromium.org>,
        Guenter Roeck <linux@roeck-us.net>,
        Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
        Maxim Kiselev <bigunclemax@gmail.com>,
        Maxim Kochetkov <fido_max@inbox.ru>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Luca Weiss <luca.weiss@fairphone.com>,
        Colin Foster <colin.foster@in-advantage.com>,
        Martin Kepplinger <martin.kepplinger@puri.sm>,
        Jean-Philippe Brucker <jpb@kernel.org>,
        kernel-team@android.com, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-gpio@vger.kernel.org,
        devicetree@vger.kernel.org, linux-renesas-soc@vger.kernel.org,
        linux-acpi@vger.kernel.org
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Precedence: bulk

On Fri, Jan 27, 2023 at 1:27 AM Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
>
> On Thu, Jan 26, 2023 at 04:11:31PM -0800, Saravana Kannan wrote:
> > Registering an irqdomain sets the flag for the fwnode. But having the
> > flag set when a device is added is interpreted by fw_devlink to mean the
> > device has already been initialized and will never probe. This prevents
> > fw_devlink from creating device links with the gpio_device as a
> > supplier. So, clear the flag before adding the device.
>
> ...
>
> > +     /*
> > +      * If fwnode doesn't belong to another device, it's safe to clear its
> > +      * initialized flag.
> > +      */
> > +     if (!gdev->dev.fwnode->dev)
> > +             fwnode_dev_initialized(gdev->dev.fwnode, false);
>
> Do not dereference fwnode in struct device. Use dev_fwnode() for that.
>
>         struct fwnode_handle *fwnode = dev_fwnode(&gdev->dev);
>
>         if (!fwnode->dev)
>                 fwnode_dev_initialized(fwnode, false);

Honestly, we should work towards NOT needing dev_fwnode(). The
function literally dereferences dev->fwnode or the one inside of_node.
So my dereference is fine. The whole "fwnode might not be set for
devices with of_node" is wrong and we should fix that instead of
writing wrappers to work around it.

Also, for now I'm going to leave this as if for the same reasons as I
mentioned in Patch 1.

>
> + Blank line.

Ack.


-Saravana

>
> >       ret = gcdev_register(gdev, gpio_devt);
> >       if (ret)
> >               return ret;
>
> --
> With Best Regards,
> Andy Shevchenko
>
>
> --
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