[PATCH v2 07/18] soc: imx: gpcv2: support system suspend/resume

[Peng Fan]

> Subject: [PATCH v2 07/18] soc: imx: gpcv2: support system suspend/resume
> 
> Our usage of runtime PM to control the hierarchy of power domains is slightly
> unusual and means that powering up a domain may fail in early system
> resume, as runtime PM is still disallowed at this stage.
> 
> However the system suspend/resume path takes care of powering down/up
> the power domains in the order defined by the device parent/child and
> power-domain provider/consumer hierarachy. So we can just runtime resume
> all our power-domain devices to allow the power-up to work properly in the
> resume path. System suspend will still disable all domains as intended.
> 
> Signed-off-by: Lucas Stach <l.stach at pengutronix.de>

Acked-by: Peng Fan <peng.fan at nxp.com>

> ---
>  drivers/soc/imx/gpcv2.c | 31 +++++++++++++++++++++++++++++++
>  1 file changed, 31 insertions(+)
> 
> diff --git a/drivers/soc/imx/gpcv2.c b/drivers/soc/imx/gpcv2.c index
> c48f37f203ab..57ed0a6bfb13 100644
> --- a/drivers/soc/imx/gpcv2.c
> +++ b/drivers/soc/imx/gpcv2.c
> @@ -947,6 +947,36 @@ static int imx_pgc_domain_remove(struct
> platform_device *pdev)
>  	return 0;
>  }
> 
> +#ifdef CONFIG_PM_SLEEP
> +static int imx_pgc_domain_suspend(struct device *dev) {
> +	int ret;
> +
> +	/*
> +	 * This may look strange, but is done so the generic PM_SLEEP code
> +	 * can power down our domain and more importantly power it up again
> +	 * after resume, without tripping over our usage of runtime PM to
> +	 * power up/down the nested domains.
> +	 */
> +	ret = pm_runtime_get_sync(dev);
> +	if (ret < 0) {
> +		pm_runtime_put_noidle(dev);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int imx_pgc_domain_resume(struct device *dev) {
> +	return pm_runtime_put(dev);
> +}
> +#endif
> +
> +static const struct dev_pm_ops imx_pgc_domain_pm_ops = {
> +	SET_SYSTEM_SLEEP_PM_OPS(imx_pgc_domain_suspend,
> imx_pgc_domain_resume)
> +};
> +
>  static const struct platform_device_id imx_pgc_domain_id[] = {
>  	{ "imx-pgc-domain", },
>  	{ },
> @@ -955,6 +985,7 @@ static const struct platform_device_id
> imx_pgc_domain_id[] = {  static struct platform_driver
> imx_pgc_domain_driver = {
>  	.driver = {
>  		.name = "imx-pgc",
> +		.pm = &imx_pgc_domain_pm_ops,
>  	},
>  	.probe    = imx_pgc_domain_probe,
>  	.remove   = imx_pgc_domain_remove,
> --
> 2.30.2