linux-kernel - Re: [PATCH v3 07/14] phy: qcom: qmp-usbc: Move reset and regulator config into PHY cfg

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Message-ID: <osav4kwxytfuxvnf26ugdw2qasd753smywsux5punuegbkxqgq@fp3r4esqiqyq>
Date: Wed, 27 Aug 2025 17:31:11 +0300
From: Dmitry Baryshkov <dmitry.baryshkov@....qualcomm.com>
To: Xiangxu Yin <xiangxu.yin@....qualcomm.com>
Cc: Rob Clark <robin.clark@....qualcomm.com>,
        Dmitry Baryshkov <lumag@...nel.org>,
        Abhinav Kumar <abhinav.kumar@...ux.dev>,
        Jessica Zhang <jessica.zhang@....qualcomm.com>,
        Sean Paul <sean@...rly.run>,
        Marijn Suijten <marijn.suijten@...ainline.org>,
        Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
        Maxime Ripard <mripard@...nel.org>,
        Thomas Zimmermann <tzimmermann@...e.de>,
        David Airlie <airlied@...il.com>, Simona Vetter <simona@...ll.ch>,
        Rob Herring <robh@...nel.org>,
        Krzysztof Kozlowski <krzk+dt@...nel.org>,
        Conor Dooley <conor+dt@...nel.org>,
        Kuogee Hsieh <quic_khsieh@...cinc.com>, Vinod Koul <vkoul@...nel.org>,
        Kishon Vijay Abraham I <kishon@...nel.org>,
        Philipp Zabel <p.zabel@...gutronix.de>, linux-arm-msm@...r.kernel.org,
        dri-devel@...ts.freedesktop.org, freedreno@...ts.freedesktop.org,
        devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-phy@...ts.infradead.org, fange.zhang@....qualcomm.com,
        yongxing.mou@....qualcomm.com, tingwei.zhang@....qualcomm.com,
        Bjorn Andersson <andersson@...nel.org>,
        Konrad Dybcio <konradybcio@...nel.org>
Subject: Re: [PATCH v3 07/14] phy: qcom: qmp-usbc: Move reset and regulator
 config into PHY cfg

On Wed, Aug 27, 2025 at 09:28:00PM +0800, Xiangxu Yin wrote:
> 
> On 8/22/2025 6:08 PM, Dmitry Baryshkov wrote:
> > On Fri, Aug 22, 2025 at 04:29:28PM +0800, Xiangxu Yin wrote:
> >> On 8/20/2025 7:30 PM, Dmitry Baryshkov wrote:
> >>> On Wed, Aug 20, 2025 at 05:34:49PM +0800, Xiangxu Yin wrote:
> >>>> Refactor reset and regulator configuration to be managed via qmp_phy_cfg
> >>>> instead of hardcoded lists. This enables per-PHY customization and
> >>>> simplifies initialization logic for USB-only and USB/DP switchable PHYs.
> >>> Please split into two patches in order to simplify reviewing.
> >>
> >> Ok, will split reset and regulator part.
> >>
> >>
> >>>> Signed-off-by: Xiangxu Yin <xiangxu.yin@....qualcomm.com>
> >>>> ---
> >>>>  drivers/phy/qualcomm/phy-qcom-qmp-usbc.c | 108 +++++++++++++++----------------
> >>>>  1 file changed, 53 insertions(+), 55 deletions(-)
> >>>>
> >>>> diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-usbc.c b/drivers/phy/qualcomm/phy-qcom-qmp-usbc.c
> >>>> index 61128d606238321d1b573655b3b987226aa2d594..4e797b7e65da0e3a827efa9a179f1c150c1b8b00 100644
> >>>> --- a/drivers/phy/qualcomm/phy-qcom-qmp-usbc.c
> >>>> +++ b/drivers/phy/qualcomm/phy-qcom-qmp-usbc.c
> >>>> @@ -421,8 +421,9 @@ struct qmp_phy_cfg {
> >>>>  	int (*configure_dp_phy)(struct qmp_usbc *qmp);
> >>>>  	int (*calibrate_dp_phy)(struct qmp_usbc *qmp);
> >>>>  
> >>>> -	/* regulators to be requested */
> >>>> -	const char * const *vreg_list;
> >>>> +	const char * const *reset_list;
> >>>> +	int num_resets;
> >>>> +	const struct regulator_bulk_data *vreg_list;
> >>>>  	int num_vregs;
> >>>>  
> >>>>  	/* array of registers with different offsets */
> >>>> @@ -453,7 +454,6 @@ struct qmp_usbc {
> >>>>  	struct clk_hw dp_pixel_hw;
> >>>>  	struct clk_bulk_data *clks;
> >>>>  	int num_clks;
> >>>> -	int num_resets;
> >>>>  	struct reset_control_bulk_data *resets;
> >>>>  	struct regulator_bulk_data *vregs;
> >>>>  
> >>>> @@ -514,9 +514,18 @@ static const char * const usb3phy_reset_l[] = {
> >>>>  	"phy_phy", "phy",
> >>>>  };
> >>>>  
> >>>> -/* list of regulators */
> >>>> -static const char * const qmp_phy_vreg_l[] = {
> >>>> -	"vdda-phy", "vdda-pll",
> >>>> +static const char * const usb3dpphy_reset_l[] = {
> >>>> +	"phy_phy", "dp_phy",
> >>>> +};
> >>>> +
> >>>> +static const struct regulator_bulk_data qmp_phy_usb_vreg_l[] = {
> >>>> +	{ .supply = "vdda-phy" },
> >>>> +	{ .supply = "vdda-pll" },
> >>> Please fill in the values for all platforms. It well might be that they
> >>> all share the same current requirements.
> >>
> >> I checked previous DP projects and found all platforms configured vdda-phy with 21.8mA and vdda-pll with 36mA.
> > No. On SDM660 and MSM8998 DP defines 73.4 mA for 0.9V supply and
> > 12.560 mA for 1.8 V supply.
> >
> >> However, I didn’t find USB load configs in downstream and from SoC related power grids:
> > Please check the actual HW documentation for those platforms.
> >
> >> QCS615
> >> L12A: VDDA_USB0_SS_1P8/VDDA_USB1_SS_1P8 Ipk:20ma
> >> L5A: VDDA_USB0_SS_0P9/VDDA_USB1_SS_0P9 Ipk:50mA
> >>
> >> sm6150
> >> L11A: VDDA_USB0_SS_1P8/VDDA_USB1_SS_1P8 Ipk:20ma
> >> L4A: VDDA_USB0_SS_0P9/VDDA_USB1_SS_0P9 Ipk:50mA
> >>
> >> SM6115
> >> L12A: VDDA_USB_SS_DP_1P8 Ipk:13.3mA
> >> L4A: VDDA_USB_SS_DP_CORE Ipk:66.1mA
> >>
> >> QCM2290
> >> L13A: VDDA_USB_SS_DP_1P8 Ipk:13.3mA
> >> L12A: VDDA_USB_SS_DP_CORE Ipk:66.1mA
> >>
> >> sdm660
> >> LDO10A: VDDA_USB_SS_1P8 Ipk:14mA
> >> LDO1B: VDDA_USB_SS_CORE Ipk:68.6mA
> >>
> >> msm8998
> >> L2A: VDDA_USB_SS_1P2 Ipk:14.2mA
> >> L1A: VDDA_USB_SS_CORE Ipk:68.6mA
> >>
> >> It seems the USB power requirements vary across platforms, and the
> >> 21800 µA load for vdda-phy exceeds the Ipk range in most cases.
> > Ipk being ?
> 
> 
> IPK: Instantaneous Peak Current
> 
> 
> >> I also tested removing the load settings for USB+DP PHY, and DP still works fine.
> > It mostly works either because we don't allow mode switching on older
> > platforms (yet) or because somebody else has already voted and that vote
> > keeps the required mode.
> >
> > As you've started looking on specifying proper current load, please
> > finish the work.
> 
> 
> Discussed with chip validation and power SW teams.
> 
> The power grid tables are primarily used to ensure each module receives 
> the correct voltage, and they define the Ipk for each submodule. 
> 
> While they don’t specify recommended regulator load values, the Ipk values
> reflect the expected power domain strength and can help estimate the voting
> strength needed for each supply.
> 
> Since regulator load is mainly used for voting, I’ll define init_load_uA in
> the next patch based on each SoC’s Ipk values to better align with hardware expectations.

If the Ipk is defined per module, then it's fine.

-- 
With best wishes
Dmitry