Re: [PATCH] phy: renesas: rcar-gen3-usb2: Add suspend/resume support

[Neil Armstrong]

On 11/18/25 15:13, Claudiu Beznea wrote:
> Hi, Neil,
>
> On 11/18/25 15:54, Neil Armstrong wrote:
> > On 11/6/25 15:41, Claudiu wrote:
> > > From: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
> > >
> > > The Renesas RZ/G3S supports a power saving mode where power to most of the
> > > SoC components is turned off. The USB PHY is among these components.
> > > Because of this the settings applied in driver probe need to be executed
> > > also on resume path. On suspend path only reset signal need to be asserted.
> > > Add suspend/resume support.
> > >
> > > Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
> > > ---
> > >
> > > This patch is built on top of patches 1/7, 2/7 at [1]
> > >
> > > [1] https://lore.kernel.org/all/20251023135810.1688415-2-
> > > claudiu.beznea.uj@xxxxxxxxxxxxxx
> > >
> > >    drivers/phy/renesas/phy-rcar-gen3-usb2.c | 66 +++++++++++++++++-------
> > >    1 file changed, 47 insertions(+), 19 deletions(-)
> > >
> > > diff --git a/drivers/phy/renesas/phy-rcar-gen3-usb2.c b/drivers/phy/
> > > renesas/phy-rcar-gen3-usb2.c
> > > index a38ead7c8055..3c063e4dea41 100644
> > > --- a/drivers/phy/renesas/phy-rcar-gen3-usb2.c
> > > +++ b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
> > > @@ -132,6 +132,7 @@ struct rcar_gen3_chan {
> > >        struct device *dev;    /* platform_device's device */
> > >        const struct rcar_gen3_phy_drv_data *phy_data;
> > >        struct extcon_dev *extcon;
> > > +    struct reset_control *rstc;
> > >        struct rcar_gen3_phy rphys[NUM_OF_PHYS];
> > >        struct regulator *vbus;
> > >        struct work_struct work;
> > > @@ -778,35 +779,24 @@ static void rcar_gen3_reset_assert(void *data)
> > >    static int rcar_gen3_phy_usb2_init_bus(struct rcar_gen3_chan *channel)
> > >    {
> > >        struct device *dev = channel->dev;
> > > -    struct reset_control *rstc;
> > >        int ret;
> > >        u32 val;
> > >    -    rstc = devm_reset_control_array_get_shared(dev);
> > > -    if (IS_ERR(rstc))
> > > -        return PTR_ERR(rstc);
> > > +    if (!channel->phy_data->init_bus)
> > > +        return 0;
> > >          ret = pm_runtime_resume_and_get(dev);
> > >        if (ret)
> > >            return ret;
> > >    -    ret = reset_control_deassert(rstc);
> > > -    if (ret)
> > > -        goto rpm_put;
> > > -
> > > -    ret = devm_add_action_or_reset(dev, rcar_gen3_reset_assert, rstc);
> > > -    if (ret)
> > > -        goto rpm_put;
> > > -
> > >        val = readl(channel->base + USB2_AHB_BUS_CTR);
> > >        val &= ~USB2_AHB_BUS_CTR_MBL_MASK;
> > >        val |= USB2_AHB_BUS_CTR_MBL_INCR4;
> > >        writel(val, channel->base + USB2_AHB_BUS_CTR);
> > >    -rpm_put:
> > >        pm_runtime_put(dev);
> > >    -    return ret;
> > > +    return 0;
> > >    }
> > >      static int rcar_gen3_phy_usb2_probe(struct platform_device *pdev)
> > > @@ -846,6 +836,18 @@ static int rcar_gen3_phy_usb2_probe(struct
> > > platform_device *pdev)
> > >            }
> > >        }
> > >    +    channel->rstc = devm_reset_control_array_get_optional_shared(dev);
> > > +    if (IS_ERR(channel->rstc))
> > > +        return PTR_ERR(channel->rstc);
> > > +
> > > +    ret = reset_control_deassert(channel->rstc);
> > > +    if (ret)
> > > +        return ret;
> > > +
> > > +    ret = devm_add_action_or_reset(dev, rcar_gen3_reset_assert, channel-
> > > > rstc);
> > > +    if (ret)
> > > +        return ret;
> > > +
> > >        /*
> > >         * devm_phy_create() will call pm_runtime_enable(&phy->dev);
> > >         * And then, phy-core will manage runtime pm for this device.
> > > @@ -861,11 +863,9 @@ static int rcar_gen3_phy_usb2_probe(struct
> > > platform_device *pdev)
> > >        platform_set_drvdata(pdev, channel);
> > >        channel->dev = dev;
> > >    -    if (channel->phy_data->init_bus) {
> > > -        ret = rcar_gen3_phy_usb2_init_bus(channel);
> > > -        if (ret)
> > > -            goto error;
> > > -    }
> >
> > I don't see why you changed the logic of calling
> > rcar_gen3_phy_usb2_init_bus(),
> > moving the reset setup and handling should be enough, no ?
> Sorry, I missed to mention it. I did it like this just to avoid this pattern:
>
> 	if (channel->phy_data->init_bus) {
> 		ret = rcar_gen3_phy_usb2_init_bus(channel);
> 		if (ret)
> 			return ret;
> 	}
>
> in both probe and resume path. The channel->phy_data->init_bus check is not
> embedded in rcar_gen3_phy_usb2_init_bus(). Please let me know if you want
> me to revert it.

It's an unrelated change, so I think it should be moved to a separate cleanup patch.

Thanks,
Neil


> Thank you,
> Claudiu