Re: [PATCH v2 1/2] phy: mediatek: hdmi: mt8195: fix uninitialized variable usage in pll_calc

From: Nick Desaulniers
Date: Mon Apr 24 2023 - 16:42:27 EST


On Fri, Apr 21, 2023 at 3:13 PM Nathan Chancellor <nathan@xxxxxxxxxx> 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 reported
> > 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-mt8195")
> > Reported-by: kernel test robot <lkp@xxxxxxxxx>
> > Signed-off-by: Guillaume Ranquet <granquet@xxxxxxxxxxxx>
>
> Reviewed-by: Nathan Chancellor <nathan@xxxxxxxxxx>
>
> 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@xxxxxxxxxxxx> (maintainer:ARM/Mediatek USB3
PHY DRIVER)
Matthias Brugger <matthias.bgg@xxxxxxxxx> (maintainer:ARM/Mediatek SoC support)

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/mediatek/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 *hdmi_phy, struct clk_hw *hw,
> > u64 tmds_clk, pixel_clk, da_hdmitx21_ref_ck, ns_hdmipll_ck, pcw;
> > u8 txpredivs[4] = { 2, 4, 6, 12 };
> > u32 fbkdiv_low;
> > - int i, ret;
> > + int i;
> >
> > pixel_clk = rate;
> > tmds_clk = 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 <= 32 && digital_div >= 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_low,
> > 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
> >
>


--
Thanks,
~Nick Desaulniers