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From:   Guo Ren <guoren@kernel.org>
Date:   Wed, 13 Dec 2023 22:51:12 +0800
Message-ID: <CAJF2gTQ2jCKO4my9pNvEDyf0R+Cro8ZE_RgvWi-ts8pD6vJ=Nw@mail.gmail.com>
Subject: Re: [PATCH] leds: sun50i-a100: avoid division-by-zero warning
To:     Arnd Bergmann <arnd@arndb.de>
Cc:     Arnd Bergmann <arnd@kernel.org>, Pavel Machek <pavel@ucw.cz>,
        Lee Jones <lee@kernel.org>, Chen-Yu Tsai <wens@csie.org>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        Samuel Holland <samuel@sholland.org>,
        Nathan Chancellor <nathan@kernel.org>,
        Palmer Dabbelt <palmer@rivosinc.com>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Bill Wendling <morbo@google.com>,
        Justin Stitt <justinstitt@google.com>,
        linux-leds@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-sunxi@lists.linux.dev, linux-kernel@vger.kernel.org,
        llvm@lists.linux.dev
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On Wed, Dec 13, 2023 at 2:32=E2=80=AFPM Arnd Bergmann <arnd@arndb.de> wrote=
:
>
> On Wed, Dec 13, 2023, at 02:26, Guo Ren wrote:
> > On Wed, Dec 13, 2023 at 5:45=E2=80=AFAM Arnd Bergmann <arnd@kernel.org>=
 wrote:
> >>  {
> >>         const struct sun50i_a100_ledc_timing *timing =3D &priv->timing=
;
> >>         unsigned long mod_freq =3D clk_get_rate(priv->mod_clk);
> >> -       u32 cycle_ns =3D NSEC_PER_SEC / mod_freq;
> >> +       u32 cycle_ns;
> >>         u32 control;
> >>
> >> +       if (!mod_freq)
> >> +               return;
> >> +
> > Shall we need err_disable_bus_clk?
> >
> > + static int sun50i_a100_ledc_set_timing(struct sun50i_a100_ledc *priv)
> > - static void sun50i_a100_ledc_set_timing(struct sun50i_a100_ledc *priv=
)
>
> I'm not worried about it too much, as there is already an error check
> on priv->mod_clk being unavailable during initialization. The case that
> the warning is about is just for build-testing on architectures that
> don't even use COMMON_CLK.
Okay

Reviewed-by: Guo Ren <guoren@kernel.org>

>
>      Arnd


--=20
Best Regards
 Guo Ren