[PATCH v2 4/5] phy: renesas: rcar-gen3-usb2: Assert PLL reset on PHY power off

[Lad, Prabhakar]

On Tue, Feb 25, 2025 at 11:01 AM Claudiu <claudiu.beznea at tuxon.dev> wrote:
>
> From: Claudiu Beznea <claudiu.beznea.uj at bp.renesas.com>
>
> Assert PLL reset on PHY power off. This saves power.
>
> Fixes: f3b5a8d9b50d ("phy: rcar-gen3-usb2: Add R-Car Gen3 USB2 PHY driver")
> Cc: stable at vger.kernel.org
> Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh at renesas.com>
> Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh at renesas.com>
> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj at bp.renesas.com>
> ---
>
> Changes in v2:
> - collected tags
> - add an empty line after definition of val to get rid of
>   the checkpatch.pl warning
>
>  drivers/phy/renesas/phy-rcar-gen3-usb2.c | 10 +++++++++-
>  1 file changed, 9 insertions(+), 1 deletion(-)
>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj at bp.renesas.com>

Cheers,
Prabhakar

> diff --git a/drivers/phy/renesas/phy-rcar-gen3-usb2.c b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
> index 5c0ceba09b67..21cf14ea3437 100644
> --- a/drivers/phy/renesas/phy-rcar-gen3-usb2.c
> +++ b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
> @@ -537,9 +537,17 @@ static int rcar_gen3_phy_usb2_power_off(struct phy *p)
>         struct rcar_gen3_chan *channel = rphy->ch;
>         int ret = 0;
>
> -       scoped_guard(spinlock_irqsave, &channel->lock)
> +       scoped_guard(spinlock_irqsave, &channel->lock) {
>                 rphy->powered = false;
>
> +               if (rcar_gen3_are_all_rphys_power_off(channel)) {
> +                       u32 val = readl(channel->base + USB2_USBCTR);
> +
> +                       val |= USB2_USBCTR_PLL_RST;
> +                       writel(val, channel->base + USB2_USBCTR);
> +               }
> +       }
> +
>         if (channel->vbus)
>                 ret = regulator_disable(channel->vbus);
>
> --
> 2.43.0
>
>