Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20220311014245.4612-1-ctcchien@nuvoton.com> <20220311014245.4612-4-ctcchien@nuvoton.com>
 <1f5e1e49-4ab0-5e06-fa8f-2a11b0fd1df9@canonical.com>
In-Reply-To: <1f5e1e49-4ab0-5e06-fa8f-2a11b0fd1df9@canonical.com>
From:   Avi Fishman <avifishman70@gmail.com>
Date:   Sun, 13 Mar 2022 22:22:17 +0200
Message-ID: <CAKKbWA7Pr8Gi-rU5_BZ32y5aiLV0tSM19WkRe+zF8spWdk5zMg@mail.gmail.com>
Subject: Re: [PATCH v3 3/3] EDAC: nuvoton: Add NPCM memory controller driver
To:     Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Cc:     Medad CChien <medadyoung@gmail.com>, rric@kernel.org,
        James Morse <james.morse@arm.com>, tony.luck@intel.com,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Borislav Petkov <bp@alien8.de>,
        Rob Herring <robh+dt@kernel.org>,
        Benjamin Fair <benjaminfair@google.com>,
        Nancy Yuen <yuenn@google.com>,
        Patrick Venture <venture@google.com>, KWLIU@nuvoton.com,
        YSCHU@nuvoton.com, JJLIU0@nuvoton.com, KFTING@nuvoton.com,
        Tomer Maimon <tmaimon77@gmail.com>,
        Tali Perry <tali.perry1@gmail.com>, ctcchien@nuvoton.com,
        linux-edac <linux-edac@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        devicetree <devicetree@vger.kernel.org>,
        OpenBMC Maillist <openbmc@lists.ozlabs.org>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Fri, Mar 11, 2022 at 11:15 AM Krzysztof Kozlowski
<krzysztof.kozlowski@canonical.com> wrote:
>
> On 11/03/2022 02:42, Medad CChien wrote:
> > Add support for Nuvoton NPCM SoC.
> >
> > Signed-off-by: Medad CChien <ctcchien@nuvoton.com>
> > ---
> >  drivers/edac/Kconfig     |   9 +
> >  drivers/edac/Makefile    |   1 +
> >  drivers/edac/npcm_edac.c | 714 +++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 724 insertions(+)
> >  create mode 100644 drivers/edac/npcm_edac.c
> >
> > diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
> > index 58ab63642e72..757e1d160640 100644
> > --- a/drivers/edac/Kconfig
> > +++ b/drivers/edac/Kconfig
> > @@ -539,4 +539,13 @@ config EDAC_DMC520
> >         Support for error detection and correction on the
> >         SoCs with ARM DMC-520 DRAM controller.
> >
> > +config EDAC_NPCM
> > +     tristate "Nuvoton NPCM DDR Memory Controller"
> > +     depends on ARCH_NPCM
>
> || COMPILE_TEST
> (and test if it compiles)
>
> (...)
>
> > +
> > +MODULE_DEVICE_TABLE(of, npcm_edac_of_match);
> > +
> > +static int npcm_edac_mc_probe(struct platform_device *pdev)
> > +{
> > +     const struct npcm_edac_platform_data *npcm_chip;
> > +     struct device *dev = &pdev->dev;
> > +     struct edac_mc_layer layers[1];
> > +     const struct of_device_id *id;
> > +     struct priv_data *priv_data;
> > +     struct mem_ctl_info *mci;
> > +     struct resource *res;
> > +     void __iomem *reg;
> > +     int ret = -ENODEV;
> > +     int irq;
> > +
> > +     id = of_match_device(npcm_edac_of_match, &pdev->dev);
> > +     if (!id)
> > +             return -ENODEV;
>
> Why do you need it? How such case is even possible?
>
> > +
> > +     npcm_chip = of_device_get_match_data(&pdev->dev);
> > +     if (!npcm_chip)
> > +             return -ENODEV;
>
> I wonder, how is it possible to have here NULL?
>
Both of_match_device() and of_device_get_match_data() can return NULL,
are we missing something?

> Best regards,
> Krzysztof

-- 
Regards,
Avi