Re: [PATCH 2/2] reset: rzg2l-usbphy-ctrl: Add suspend/resume support

[Philipp Zabel]

On Do, 2025-11-06 at 16:33 +0200, Claudiu wrote:
> From: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
> 
> The RZ/G2L USBPHY control driver is also used on the RZ/G3S SoC.
> The RZ/G3S SoC supports a power-saving mode in which power to most USB
> components (including the USBPHY control block) is turned off. Because of
> this, the USBPHY control block needs to be reconfigured when returning
> from power-saving mode.
> 
> Add suspend/resume support to handle runtime suspend/resume of the device,
> assert/deassert the reset signal, and reinitialize the USBPHY control
> block.
> 
> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
> ---
>  drivers/reset/reset-rzg2l-usbphy-ctrl.c | 94 +++++++++++++++++++++----
>  1 file changed, 79 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/reset/reset-rzg2l-usbphy-ctrl.c b/drivers/reset/reset-rzg2l-usbphy-ctrl.c
> index 9ce0c1f5d465..8ba65839f6e4 100644
> --- a/drivers/reset/reset-rzg2l-usbphy-ctrl.c
> +++ b/drivers/reset/reset-rzg2l-usbphy-ctrl.c
[...]
> @@ -266,10 +273,67 @@ static void rzg2l_usbphy_ctrl_remove(struct platform_device *pdev)
>  	reset_control_assert(priv->rstc);
>  }
>  
> +static int rzg2l_usbphy_ctrl_suspend(struct device *dev)
> +{
> +	struct rzg2l_usbphy_ctrl_priv *priv = dev_get_drvdata(dev);
> +	int ret;
> +
> +	pm_runtime_put(dev);

Should this be pm_runtime_put_sync(dev)?

> +
> +	ret = reset_control_assert(priv->rstc);
> +	if (ret)
> +		goto rpm_resume;
> +
> +	ret = rzg2l_usbphy_ctrl_set_pwrrdy(priv->pwrrdy, false);

This sets PWRRDY=1, and needs to be set after MSTOP=1,CLK_ON=0,
according to 58128aa88867 ("reset: rzg2l-usbphy-ctrl: Add support for
USB PWRRDY"). I assume MSTOP/CLK_ON refer to the PHY clock in that
description, so the pm_runtime_put() above is required to have taken
effect here.



regards
Philipp