Re: [PATCH 1/2] drm/mediatek/hdmi: Use syscon_regmap_lookup_by_phandle_args

["CK Hu (胡俊光)" <ck.hu@mediatek.com>]

On Sun, 2025-01-12 at 14:47 +0100, Krzysztof Kozlowski wrote:
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> 
> 
> Use syscon_regmap_lookup_by_phandle_args() which is a wrapper over
> syscon_regmap_lookup_by_phandle() combined with getting the syscon
> argument.  Except simpler code this annotates within one line that given
> phandle has arguments, so grepping for code would be easier.
> 
> There is also no real benefit in printing errors on missing syscon
> argument, because this is done just too late: runtime check on
> static/build-time data.  Dtschema and Devicetree bindings offer the
> static/build-time check for this already.

Reviewed-by: CK Hu <ck.hu@mediatek.com>

I've not decided to apply this patch first or Angelo's patch first.
I'll fix conflict when I apply both patch.

Regards,
CK

> 
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> ---
>  drivers/gpu/drm/mediatek/mtk_hdmi.c | 14 +++++---------
>  1 file changed, 5 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi.c b/drivers/gpu/drm/mediatek/mtk_hdmi.c
> index ca82bc829cb9..4b0eb7dc25d8 100644
> --- a/drivers/gpu/drm/mediatek/mtk_hdmi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_hdmi.c
> @@ -1458,15 +1458,11 @@ static int mtk_hdmi_dt_parse_pdata(struct mtk_hdmi *hdmi,
>          * MMSYS_CONFIG device and the register offset of the HDMI_SYS_CFG
>          * registers it contains.
>          */
> -       regmap = syscon_regmap_lookup_by_phandle(np, "mediatek,syscon-hdmi");
> -       ret = of_property_read_u32_index(np, "mediatek,syscon-hdmi", 1,
> -                                        &hdmi->sys_offset);
> -       if (IS_ERR(regmap))
> -               ret = PTR_ERR(regmap);
> -       if (ret) {
> -               dev_err(dev,
> -                       "Failed to get system configuration registers: %d\n",
> -                       ret);
> +       regmap = syscon_regmap_lookup_by_phandle_args(np, "mediatek,syscon-hdmi",
> +                                                     1, &hdmi->sys_offset);
> +       if (IS_ERR(regmap)) {
> +               ret = dev_err_probe(dev, PTR_ERR(regmap),
> +                                   "Failed to get system configuration registers\n");
>                 goto put_device;
>         }
>         hdmi->sys_regmap = regmap;
> --
> 2.43.0
> 
>