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Subject: Re: [PATCH] clk: qcom: clk-rpmh: Fix if statement to match comment
From:   Stephen Boyd <sboyd@kernel.org>
Cc:     agross@kernel.org, bjorn.andersson@linaro.org,
        linux-arm-msm@vger.kernel.org, linux-clk@vger.kernel.org,
        linux-kernel@vger.kernel.org
To:     Li Zhengyu <lizhengyu3@huawei.com>, quic_tdas@quicinc.com
Date:   Fri, 10 Jun 2022 12:58:54 -0700
User-Agent: alot/0.10
Message-Id: <20220610195856.A2D7EC3411C@smtp.kernel.org>
Precedence: bulk

Quoting Li Zhengyu (2022-05-31 02:45:39)
> (c->state) is u32, (enable) is bool. It returns false when
> (c->state) > 1 and (enable) is true. Convert (c->state) to bool.
>=20
> Signed-off-by: Li Zhengyu <lizhengyu3@huawei.com>

Nice catch! It looks like it fixes an optimization, where we don't want
to run through and check has_state_changed() if this clk is already
enabled or disabled. But how does this ever happen? The clk framework
already reference counts prepare/unprepare, so how can we get into this
function when the condition would be true, after this patch?

I think we can simply remove the if condition entirely. Do you agree?

> ---
>  drivers/clk/qcom/clk-rpmh.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>=20
> diff --git a/drivers/clk/qcom/clk-rpmh.c b/drivers/clk/qcom/clk-rpmh.c
> index aed907982344..851e127432a9 100644
> --- a/drivers/clk/qcom/clk-rpmh.c
> +++ b/drivers/clk/qcom/clk-rpmh.c
> @@ -196,7 +196,7 @@ static int clk_rpmh_aggregate_state_send_command(stru=
ct clk_rpmh *c,
>         int ret;
> =20
>         /* Nothing required to be done if already off or on */
> -       if (enable =3D=3D c->state)
> +       if (enable =3D=3D !!c->state)
>                 return 0;
> =20
>         c->state =3D enable ? c->valid_state_mask : 0;