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References: <20231206113138.3576492-1-lukasz.luba@arm.com> <20231206113138.3576492-3-lukasz.luba@arm.com>
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From: "Rafael J. Wysocki" <rafael@kernel.org>
Date: Wed, 20 Dec 2023 15:07:59 +0100
Message-ID: <CAJZ5v0jSt87KXB0HPXhc+T05K0FgQNKzrNVj4NqYJ+a_WCJbWw@mail.gmail.com>
Subject: Re: [PATCH 2/5] thermal: gov_power_allocator: Refactor check_power_actors()
To: Lukasz Luba <lukasz.luba@arm.com>
Cc: linux-kernel@vger.kernel.org, daniel.lezcano@linaro.org, rafael@kernel.org, 
	linux-pm@vger.kernel.org, rui.zhang@intel.com
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On Wed, Dec 6, 2023 at 12:30=E2=80=AFPM Lukasz Luba <lukasz.luba@arm.com> w=
rote:
>
> Refactor check_power_actors() to make it possible for re-use in the
> upcoming new callback.

I would say "In preparation for a subsequent change, rearrange
check_power_actors()".
>
> No intentional functional impact.
>
> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
> ---
>  drivers/thermal/gov_power_allocator.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/thermal/gov_power_allocator.c b/drivers/thermal/gov_=
power_allocator.c
> index 785fff14223d..38e1e89ba10c 100644
> --- a/drivers/thermal/gov_power_allocator.c
> +++ b/drivers/thermal/gov_power_allocator.c
> @@ -581,8 +581,9 @@ static void allow_maximum_power(struct thermal_zone_d=
evice *tz, bool update)
>   * power actor API. The warning should help to investigate the issue, wh=
ich
>   * could be e.g. lack of Energy Model for a given device.
>   *
> - * Return: 0 on success, -EINVAL if any cooling device does not implemen=
t
> - * the power actor API.
> + * Return number of cooling devices or -EINVAL if any cooling device doe=
s not
> + * implement the power actor API. Return value 0 is also valid since coo=
ling
> + * devices might be attached later.

I would say "If all of the cooling devices currently attached to @tz
implement the power actor API, return the number of them (which may be
0, because some cooling devices may be attached later).  Otherwise,
return -EINVAL."

>   */
>  static int check_power_actors(struct thermal_zone_device *tz,
>                               struct power_allocator_params *params)
> @@ -597,8 +598,9 @@ static int check_power_actors(struct thermal_zone_dev=
ice *tz,
>                 if (!cdev_is_power_actor(instance->cdev)) {
>                         dev_warn(&tz->device, "power_allocator: %s is not=
 a power actor\n",
>                                  instance->cdev->type);
> -                       ret =3D -EINVAL;
> +                       return -EINVAL;
>                 }
> +               ret++;
>         }
>
>         return ret;
> @@ -631,7 +633,7 @@ static int power_allocator_bind(struct thermal_zone_d=
evice *tz)
>         }
>
>         ret =3D check_power_actors(tz, params);
> -       if (ret) {
> +       if (ret < 0) {
>                 dev_warn(&tz->device, "power_allocator: binding failed\n"=
);
>                 kfree(params);
>                 return ret;
> --