Re: [PATCH v9 22/23] scsi: ufs: mediatek: Remove undocumented "clk-scale-up-vcore-min"

["Chaotian Jing (井朝天)" <Chaotian.Jing@mediatek.com>]

On Fri, 2026-03-06 at 14:25 +0100, Nicolas Frattaroli wrote:
> The MediaTek UFS driver contains support for an undocumented,
> non-vendor-prefixed u32 property named "clk-scale-up-vcore-min".
> 
> Since it is not part of any binding, and would not pass a bindings
> review in its current form, remove it.
> 
> To return this functionality, it needs to be resubmitted in a series
> that also introduces it to the binding, and justifies what it is used
> for. Compatibility with downstream device trees is not a valid
> justification for its existence.
> 
Is it possible to add the "clk-scale-up-vcore-min" to the DT binding
firstly ? the reason is that MT8196 supports UFS4.0, and make the VCore
at least 0.65V is the MUST condition that to run HS-G5 mode.
> Reviewed-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno@collabora.com>
> Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
> ---
>  drivers/ufs/host/ufs-mediatek.c | 19 -------------------
>  1 file changed, 19 deletions(-)
> 
> diff --git a/drivers/ufs/host/ufs-mediatek.c b/drivers/ufs/host/ufs-
> mediatek.c
> index ae6735683f76..1dfc299b93b5 100644
> --- a/drivers/ufs/host/ufs-mediatek.c
> +++ b/drivers/ufs/host/ufs-mediatek.c
> @@ -880,8 +880,6 @@ static void ufs_mtk_init_clocks(struct ufs_hba
> *hba)
>  	struct ufs_mtk_host *host = ufshcd_get_variant(hba);
>  	struct list_head *head = &hba->clk_list_head;
>  	struct ufs_clk_info *clki, *clki_tmp;
> -	struct device *dev = hba->dev;
> -	u32 volt;
>  
>  	/*
>  	 * Find private clocks and store them in struct ufs_mtk_clk.
> @@ -918,24 +916,7 @@ static void ufs_mtk_init_clocks(struct ufs_hba
> *hba)
>  	if (!ufs_mtk_is_clk_scale_ready(hba)) {
>  		hba->caps &= ~UFSHCD_CAP_CLK_SCALING;
>  		dev_info(hba->dev, "%s: Clock scaling unavailable",
> __func__);
> -		return;
> -	}
> -
> -	if (!host->reg_vcore)
> -		return;
> -
> -	if (of_property_read_u32(dev->of_node, "clk-scale-up-vcore-
> min",
> -				 &volt)) {
> -		dev_info(dev, "failed to get clk-scale-up-vcore-min");
> -		return;
>  	}
> -
> -	host->mclk.vcore_volt = volt;
> -
> -	/* If default boot is max gear, request vcore */
> -	if (volt && host->clk_scale_up)
> -		if (regulator_set_voltage(host->reg_vcore, volt,
> INT_MAX))
> -			dev_err(hba->dev, "Failed to set vcore to
> %d\n", volt);
>  }
>  
>  static void ufs_mtk_setup_clk_gating(struct ufs_hba *hba)
>