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References: <20230413-fixes-for-mt8195-hdmi-phy-v2-0-bbad62e64321@baylibre.com>
 <20230413-fixes-for-mt8195-hdmi-phy-v2-1-bbad62e64321@baylibre.com> <20230421221330.GA3657732@dev-arch.thelio-3990X>
In-Reply-To: <20230421221330.GA3657732@dev-arch.thelio-3990X>
From:   Nick Desaulniers <ndesaulniers@google.com>
Date:   Mon, 24 Apr 2023 13:42:08 -0700
Message-ID: <CAKwvOd=5szkx5yA0bxcyktx85opAwLrB3_4n13SMV7p3m9x7LQ@mail.gmail.com>
Subject: Re: [PATCH v2 1/2] phy: mediatek: hdmi: mt8195: fix uninitialized
 variable usage in pll_calc
To:     Matthias Brugger <matthias.bgg@gmail.com>,
        Chunfeng Yun <chunfeng.yun@mediatek.com>,
        Vinod Koul <vkoul@kernel.org>
Cc:     Guillaume Ranquet <granquet@baylibre.com>,
        Chun-Kuang Hu <chunkuang.hu@kernel.org>,
        Philipp Zabel <p.zabel@pengutronix.de>,
        Kishon Vijay Abraham I <kishon@kernel.org>,
        AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>,
        dri-devel@lists.freedesktop.org,
        linux-mediatek@lists.infradead.org,
        linux-arm-kernel@lists.infradead.org,
        linux-phy@lists.infradead.org, linux-kernel@vger.kernel.org,
        kernel test robot <lkp@intel.com>, llvm@lists.linux.dev,
        Nathan Chancellor <nathan@kernel.org>
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On Fri, Apr 21, 2023 at 3:13=E2=80=AFPM Nathan Chancellor <nathan@kernel.or=
g> wrote:
>
> On Fri, Apr 14, 2023 at 06:07:46PM +0200, Guillaume Ranquet wrote:
> > The ret variable in mtk_hdmi_pll_calc() was used unitialized as reporte=
d
> > by the kernel test robot.
> >
> > Fix the issue by removing the variable altogether and testing out the
> > return value of mtk_hdmi_pll_set_hw()
> >
> > Fixes: 45810d486bb44 ("phy: mediatek: add support for phy-mtk-hdmi-mt81=
95")
> > Reported-by: kernel test robot <lkp@intel.com>
> > Signed-off-by: Guillaume Ranquet <granquet@baylibre.com>
>
> Reviewed-by: Nathan Chancellor <nathan@kernel.org>
>
> Can somebody pick this up? It fixes a rather obvious warning, which is
> breaking clang builds (as evidenced by three versions of the same fix).

$ ./scripts/get_maintainer.pl -f
drivers/phy/mediatek/phy-mtk-hdmi-mt8195.c | grep maintainer
Chunfeng Yun <chunfeng.yun@mediatek.com> (maintainer:ARM/Mediatek USB3
PHY DRIVER)
Matthias Brugger <matthias.bgg@gmail.com> (maintainer:ARM/Mediatek SoC supp=
ort)

Chunfeng, Matthias, can one of you pick this up, please?

Or Vinod who merged 45810d486bb44 FWICT?

>
> > ---
> >  drivers/phy/mediatek/phy-mtk-hdmi-mt8195.c | 8 ++------
> >  1 file changed, 2 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/phy/mediatek/phy-mtk-hdmi-mt8195.c b/drivers/phy/m=
ediatek/phy-mtk-hdmi-mt8195.c
> > index abfc077fb0a8..054b73cb31ee 100644
> > --- a/drivers/phy/mediatek/phy-mtk-hdmi-mt8195.c
> > +++ b/drivers/phy/mediatek/phy-mtk-hdmi-mt8195.c
> > @@ -213,7 +213,7 @@ static int mtk_hdmi_pll_calc(struct mtk_hdmi_phy *h=
dmi_phy, struct clk_hw *hw,
> >       u64 tmds_clk, pixel_clk, da_hdmitx21_ref_ck, ns_hdmipll_ck, pcw;
> >       u8 txpredivs[4] =3D { 2, 4, 6, 12 };
> >       u32 fbkdiv_low;
> > -     int i, ret;
> > +     int i;
> >
> >       pixel_clk =3D rate;
> >       tmds_clk =3D pixel_clk;
> > @@ -292,13 +292,9 @@ static int mtk_hdmi_pll_calc(struct mtk_hdmi_phy *=
hdmi_phy, struct clk_hw *hw,
> >       if (!(digital_div <=3D 32 && digital_div >=3D 1))
> >               return -EINVAL;
> >
> > -     mtk_hdmi_pll_set_hw(hw, PLL_PREDIV, fbkdiv_high, fbkdiv_low,
> > +     return mtk_hdmi_pll_set_hw(hw, PLL_PREDIV, fbkdiv_high, fbkdiv_lo=
w,
> >                           PLL_FBKDIV_HS3, posdiv1, posdiv2, txprediv,
> >                           txposdiv, digital_div);
> > -     if (ret)
> > -             return -EINVAL;
> > -
> > -     return 0;
> >  }
> >
> >  static int mtk_hdmi_pll_drv_setting(struct clk_hw *hw)
> >
> > --
> > 2.40.0
> >
>


--=20
Thanks,
~Nick Desaulniers