Re: [PATCH v2 2/2] phy: qcom-snps-femto-v2: add system sleep PM ops

[Andrew Halaney <ahalaney@redhat.com>]

On Mon, Jun 05, 2023 at 02:44:54PM -0400, Adrien Thierry wrote:
> Add the system sleep suspend and resume callbacks, reusing the same code
> as the runtime suspend and resume callbacks.

It would be nice (imo) to reference the downstream driver you used as a
reference if you spin a v3.

> 
> Signed-off-by: Adrien Thierry <athierry@redhat.com>
> ---
> I'm still a bit confused as to what the difference is between
> suspend/resume PM ops and the struct usb_phy set_suspend() callback.
> Please tell me if I should be populating the latter instead.

My understanding is usb_phy is a legacy thing, and that the generic phys
are the way to go (which this is).

Looking at dwc3 for example, you can see it uses:

	phy_power_off(dwc->usb3_generic_phy);
	phy_power_off(dwc->usb2_generic_phy);

	usb_phy_set_suspend(dwc->usb3_phy, 1);
	usb_phy_set_suspend(dwc->usb2_phy, 1);

so it handles both the generic phy (like this) and the usb_phy.
This driver doesn't implement the power_off callback, but phy_power_off
is also pm_runtime aware, so calling phy_power_off in a controller still
achieves similar behavior (although I'm following right
phy_init/phy_exit also are pm_runtime aware, so I think it would be at
that point that the ops get called).

This all assumes a user enables pm_runtime in sysfs for this driver.

> 
>  drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c | 18 ++++++++++--------
>  1 file changed, 10 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c b/drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c
> index ce1d2f8b568a..378a5029f61e 100644
> --- a/drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c
> +++ b/drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c
> @@ -179,7 +179,7 @@ static inline void qcom_snps_hsphy_write_mask(void __iomem *base, u32 offset,
>  	readl_relaxed(base + offset);
>  }
>  
> -static int qcom_snps_hsphy_suspend(struct qcom_snps_hsphy *hsphy)
> +static int qcom_snps_hsphy_do_suspend(struct qcom_snps_hsphy *hsphy)
>  {
>  	dev_dbg(&hsphy->phy->dev, "Suspend QCOM SNPS PHY\n");
>  
> @@ -199,7 +199,7 @@ static int qcom_snps_hsphy_suspend(struct qcom_snps_hsphy *hsphy)
>  	return 0;
>  }
>  
> -static int qcom_snps_hsphy_resume(struct qcom_snps_hsphy *hsphy)
> +static int qcom_snps_hsphy_do_resume(struct qcom_snps_hsphy *hsphy)
>  {
>  	int ret;
>  
> @@ -214,25 +214,25 @@ static int qcom_snps_hsphy_resume(struct qcom_snps_hsphy *hsphy)
>  	return 0;
>  }
>  
> -static int __maybe_unused qcom_snps_hsphy_runtime_suspend(struct device *dev)
> +static int __maybe_unused qcom_snps_hsphy_suspend(struct device *dev)
>  {
>  	struct qcom_snps_hsphy *hsphy = dev_get_drvdata(dev);
>  
>  	if (!hsphy->phy_initialized)
>  		return 0;
>  
> -	qcom_snps_hsphy_suspend(hsphy);
> +	qcom_snps_hsphy_do_suspend(hsphy);

Deserves its own patch, but can you return qcom_snps_hsphy_do_suspend/resume
as part of your clean up in this series?

>  	return 0;
>  }
>  
> -static int __maybe_unused qcom_snps_hsphy_runtime_resume(struct device *dev)
> +static int __maybe_unused qcom_snps_hsphy_resume(struct device *dev)
>  {
>  	struct qcom_snps_hsphy *hsphy = dev_get_drvdata(dev);
>  
>  	if (!hsphy->phy_initialized)
>  		return 0;
>  
> -	qcom_snps_hsphy_resume(hsphy);
> +	qcom_snps_hsphy_do_resume(hsphy);
>  	return 0;
>  }
>  
> @@ -518,8 +518,10 @@ static const struct of_device_id qcom_snps_hsphy_of_match_table[] = {
>  MODULE_DEVICE_TABLE(of, qcom_snps_hsphy_of_match_table);
>  
>  static const struct dev_pm_ops qcom_snps_hsphy_pm_ops = {
> -	SET_RUNTIME_PM_OPS(qcom_snps_hsphy_runtime_suspend,
> -			   qcom_snps_hsphy_runtime_resume, NULL)
> +	SET_RUNTIME_PM_OPS(qcom_snps_hsphy_suspend,
> +			   qcom_snps_hsphy_resume, NULL)
> +	SET_SYSTEM_SLEEP_PM_OPS(qcom_snps_hsphy_suspend,
> +				qcom_snps_hsphy_resume)
>  };
>  
>  static void qcom_snps_hsphy_override_param_update_val(
> -- 
> 2.40.1
>