Re: [PATCH] usb: dwc2: disable platform lowlevel hw resources during shutdown

From: Minas Harutyunyan
Date: Mon Jun 30 2025 - 02:40:53 EST




On 6/29/25 13:46, Jisheng Zhang wrote:
> On some SoC platforms, in shutdown stage, most components' power is cut
> off, but there's still power supply to the so called always-on
> domain, so if the dwc2's regulator is from the always-on domain, we
> need to explicitly disable it to save power.
>
> Disable platform lowlevel hw resources such as phy, clock and
> regulators etc. in device shutdown hook to reduce non-necessary power
> consumption when the platform enters shutdown stage.
>
> Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxx>

Acked-by: Minas Harutyunyan <hminas@xxxxxxxxxxxx>

> ---
> drivers/usb/dwc2/platform.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
> index 12b4dc07d08a..3f83ecc9fc23 100644
> --- a/drivers/usb/dwc2/platform.c
> +++ b/drivers/usb/dwc2/platform.c
> @@ -371,6 +371,9 @@ static void dwc2_driver_shutdown(struct platform_device *dev)
>
> dwc2_disable_global_interrupts(hsotg);
> synchronize_irq(hsotg->irq);
> +
> + if (hsotg->ll_hw_enabled)
> + dwc2_lowlevel_hw_disable(hsotg);
> }
>
> /**