Re: [PATCH v6 1/9] mtk-mdp: propagate errors from clock_on

From: Enric Balletbo Serra <eballetbo@gmail.com>
To: Eizan Miyamoto <eizan@chromium.org>
Cc: linux-kernel <linux-kernel@vger.kernel.org>,
	Chen-Yu Tsai <wenst@chromium.org>,
	Houlong Wei <houlong.wei@mediatek.com>,
	Yong Wu <yong.wu@mediatek.com>,
	Enric Balletbo i Serra <enric.balletbo@collabora.com>,
	devicetree <devicetree@vger.kernel.org>,
	Chun-Kuang Hu <chunkuang.hu@kernel.org>,
	Andrew-CT Chen <andrew-ct.chen@mediatek.com>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	Mauro Carvalho Chehab <mchehab@kernel.org>,
	Minghsiu Tsai <minghsiu.tsai@mediatek.com>,
	Linux ARM <linux-arm-kernel@lists.infradead.org>,
	Linux Media Mailing List <linux-media@vger.kernel.org>,
	"moderated list:ARM/Mediatek SoC support" 
	<linux-mediatek@lists.infradead.org>
Subject: Re: [PATCH v6 1/9] mtk-mdp: propagate errors from clock_on
Date: Tue, 3 Aug 2021 12:26:59 +0200	[thread overview]
Message-ID: <CAFqH_53NWzhrSWqf-1qYqN7d7TRzh5g4u1+Z_3VnzoS=_CGzqg@mail.gmail.com> (raw)
In-Reply-To: <20210802220943.v6.1.I9db0d408ef79d300672ec0311a6bee9556801631@changeid>

Hi Eizan,

Thank you for your patch.

Missatge de Eizan Miyamoto <eizan@chromium.org> del dia dl., 2 d’ag.
2021 a les 14:13:
>
> Up until this change, many errors were logged but ignored when powering
> on clocks inside mtk_mdp_core. This change tries to do a better job at
> propagating errors back to the power management framework.
>
> Signed-off-by: Eizan Miyamoto <eizan@chromium.org>

Reviewed-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

> ---
>
> (no changes since v1)
>
>  drivers/media/platform/mtk-mdp/mtk_mdp_comp.c | 25 ++++++++++++-----
>  drivers/media/platform/mtk-mdp/mtk_mdp_comp.h |  2 +-
>  drivers/media/platform/mtk-mdp/mtk_mdp_core.c | 27 ++++++++++++++-----
>  3 files changed, 39 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/media/platform/mtk-mdp/mtk_mdp_comp.c b/drivers/media/platform/mtk-mdp/mtk_mdp_comp.c
> index b3426a551bea..76e295c8d9bc 100644
> --- a/drivers/media/platform/mtk-mdp/mtk_mdp_comp.c
> +++ b/drivers/media/platform/mtk-mdp/mtk_mdp_comp.c
> @@ -13,10 +13,9 @@
>
>  #include "mtk_mdp_comp.h"
>
> -
> -void mtk_mdp_comp_clock_on(struct device *dev, struct mtk_mdp_comp *comp)
> +int mtk_mdp_comp_clock_on(struct device *dev, struct mtk_mdp_comp *comp)
>  {
> -       int i, err;
> +       int i, err, status;
>
>         if (comp->larb_dev) {
>                 err = mtk_smi_larb_get(comp->larb_dev);
> @@ -30,11 +29,23 @@ void mtk_mdp_comp_clock_on(struct device *dev, struct mtk_mdp_comp *comp)
>                 if (IS_ERR(comp->clk[i]))
>                         continue;
>                 err = clk_prepare_enable(comp->clk[i]);
> -               if (err)
> -                       dev_err(dev,
> -                       "failed to enable clock, err %d. type:%d i:%d\n",
> -                               err, comp->type, i);
> +               if (err) {
> +                       status = err;
> +                       dev_err(dev, "failed to enable clock, err %d. i:%d\n", err, i);
> +                       goto err_clk_prepare_enable;
> +               }
> +       }
> +
> +       return 0;
> +
> +err_clk_prepare_enable:
> +       for (--i; i >= 0; i--) {
> +               if (IS_ERR(comp->clk[i]))
> +                       continue;
> +               clk_disable_unprepare(comp->clk[i]);

nit: We could use bulk functions here, but that's probably a follow-up patch.

>         }
> +
> +       return status;
>  }
>
>  void mtk_mdp_comp_clock_off(struct device *dev, struct mtk_mdp_comp *comp)
> diff --git a/drivers/media/platform/mtk-mdp/mtk_mdp_comp.h b/drivers/media/platform/mtk-mdp/mtk_mdp_comp.h
> index 7897766c96bb..92ab5249bcad 100644
> --- a/drivers/media/platform/mtk-mdp/mtk_mdp_comp.h
> +++ b/drivers/media/platform/mtk-mdp/mtk_mdp_comp.h
> @@ -41,7 +41,7 @@ int mtk_mdp_comp_init(struct device *dev, struct device_node *node,
>                       struct mtk_mdp_comp *comp,
>                       enum mtk_mdp_comp_type comp_type);
>  void mtk_mdp_comp_deinit(struct device *dev, struct mtk_mdp_comp *comp);
> -void mtk_mdp_comp_clock_on(struct device *dev, struct mtk_mdp_comp *comp);
> +int mtk_mdp_comp_clock_on(struct device *dev, struct mtk_mdp_comp *comp);
>  void mtk_mdp_comp_clock_off(struct device *dev, struct mtk_mdp_comp *comp);
>
>
> diff --git a/drivers/media/platform/mtk-mdp/mtk_mdp_core.c b/drivers/media/platform/mtk-mdp/mtk_mdp_core.c
> index 976aa1f4829b..412bbec0f735 100644
> --- a/drivers/media/platform/mtk-mdp/mtk_mdp_core.c
> +++ b/drivers/media/platform/mtk-mdp/mtk_mdp_core.c
> @@ -52,13 +52,28 @@ static const struct of_device_id mtk_mdp_of_ids[] = {
>  };
>  MODULE_DEVICE_TABLE(of, mtk_mdp_of_ids);
>
> -static void mtk_mdp_clock_on(struct mtk_mdp_dev *mdp)
> +static int mtk_mdp_clock_on(struct mtk_mdp_dev *mdp)
>  {
> -       struct device *dev = &mdp->pdev->dev;
>         struct mtk_mdp_comp *comp_node;
> +       int status;
> +       struct device *dev = &mdp->pdev->dev;
> +       int err;
>
> -       list_for_each_entry(comp_node, &mdp->comp_list, node)
> -               mtk_mdp_comp_clock_on(dev, comp_node);
> +       list_for_each_entry(comp_node, &mdp->comp_list, node) {
> +               err = mtk_mdp_comp_clock_on(dev, comp_node);
> +               if (err) {
> +                       status = err;
> +                       goto err_mtk_mdp_comp_clock_on;
> +               }
> +       }
> +
> +       return 0;
> +
> +err_mtk_mdp_comp_clock_on:
> +       list_for_each_entry_continue_reverse(comp_node, &mdp->comp_list, node)
> +               mtk_mdp_comp_clock_off(dev, comp_node);
> +
> +       return status;
>  }
>
>  static void mtk_mdp_clock_off(struct mtk_mdp_dev *mdp)
> @@ -274,9 +289,7 @@ static int __maybe_unused mtk_mdp_pm_resume(struct device *dev)
>  {
>         struct mtk_mdp_dev *mdp = dev_get_drvdata(dev);
>
> -       mtk_mdp_clock_on(mdp);
> -
> -       return 0;
> +       return mtk_mdp_clock_on(mdp);
>  }
>
>  static int __maybe_unused mtk_mdp_suspend(struct device *dev)
> --
> 2.32.0.554.ge1b32706d8-goog
>