Re: [PATCH v1 05/17] drm/mediatek: hdmi: use a syscon/regmap instead of iomem

[AngeloGioacchino Del Regno]

Il 19/09/22 18:56, Guillaume Ranquet ha scritto:
> To prepare support for newer chips that need to share their address
> range with a dedicated ddc driver, move to a syscon.
>
> Signed-off-by: Guillaume Ranquet <granquet@xxxxxxxxxxxx>
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi.c b/drivers/gpu/drm/mediatek/mtk_hdmi.c
> index 3196189429bc..5cd05d4fe1a9 100644
> --- a/drivers/gpu/drm/mediatek/mtk_hdmi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_hdmi.c

..snip..

> @@ -1428,7 +1413,6 @@ static int mtk_hdmi_dt_parse_pdata(struct mtk_hdmi *hdmi,
>   	struct device_node *cec_np, *remote, *i2c_np;
>   	struct platform_device *cec_pdev;
>   	struct regmap *regmap;
> -	struct resource *mem;
>   	int ret;
>   
>   	ret = mtk_hdmi_get_all_clk(hdmi, np);
> @@ -1474,8 +1458,7 @@ static int mtk_hdmi_dt_parse_pdata(struct mtk_hdmi *hdmi,
>   	}
>   	hdmi->sys_regmap = regmap;
>   
> -	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> -	hdmi->regs = devm_ioremap_resource(dev, mem);
> +	hdmi->regs = syscon_node_to_regmap(dev->of_node);

Nack. You're breaking ABI, this will force everyone to add syscon to devicetree,
hence this breaks retrocompatibility with old devicetrees.

Hint: not here, device_node_to_regmap()

Regards,
Angelo

>   	if (IS_ERR(hdmi->regs)) {
>   		ret = PTR_ERR(hdmi->regs);
>   		goto put_device;