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.

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 e863e4f8af55..dfa104207cc6 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)

-- 
2.53.0

On Mon, 2026-02-16 at 14:37 +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.
> 
> Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>

Can MT8196 work on Gear 5 without raising Vcore?
I'm afraid it might cause problems.
Maybe we can add the correct binding for MT8196?

Thanks
Peter

Il 25/02/26 11:37, Peter Wang (王信友) ha scritto:
> On Mon, 2026-02-16 at 14:37 +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.
>>
>> Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
> 
> Can MT8196 work on Gear 5 without raising Vcore?
> I'm afraid it might cause problems.
> Maybe we can add the correct binding for MT8196?
> 

Might cause problems as much as literally on every other MediaTek SoC with the
current version of this driver.

Besides, the right way of declaring freq<->voltage relationship is with OPP
tables, not with custom properties invented out of the blue - and support for OPPs
being generic is already supported in UFSHCI, so... moral of the story:

As long as the platform is correctly configured in the devicetree, it's going to
work without any kind of issues.

Regards,
Angelo

> Thanks
> Peter

On Wednesday, 25 February 2026 11:37:27 Central European Standard Time Peter Wang (王信友) wrote:
> On Mon, 2026-02-16 at 14:37 +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.
> > 
> > Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
> 
> Can MT8196 work on Gear 5 without raising Vcore?

I do not have access to the documentation to answer this question.
However, you likely do.

> I'm afraid it might cause problems.
> Maybe we can add the correct binding for MT8196?

The correct binding is to do this with OPPs instead, which is a
future task that can be tackled (by someone else) once the broad
cleanups in this series have landed.

Adding a "clk-scale-up-vcore-min" property to the MediaTek UFS
binding would not pass DT bindings review.

> 
> Thanks
> Peter
> 

On Wed, 2026-02-25 at 13:56 +0100, Nicolas Frattaroli wrote:
> The correct binding is to do this with OPPs instead, which is a
> future task that can be tackled (by someone else) once the broad
> cleanups in this series have landed.
> 
> Adding a "clk-scale-up-vcore-min" property to the MediaTek UFS
> binding would not pass DT bindings review.
> 
> 

Hi AngeloGioacchino, Nicolas,

Sure, it is also a feature task to add the OPP table.

Thanks
Peter