Re: [PATCH 10/26] drm: imx/dcss: Remove #ifdef guards for PM related functions

[Laurentiu Palcu]

Hi Paul,

On Mon, Nov 07, 2022 at 05:50:50PM +0000, Paul Cercueil wrote:
> Use the EXPORT_GPL_DEV_PM_OPS() and pm_ptr() macros to handle the PM
> callbacks.
> 
> These macros allow the PM functions to be automatically dropped by the
> compiler when CONFIG_PM is disabled, without having to use #ifdef
> guards.
> 
> This has the advantage of always compiling these functions in,
> independently of any Kconfig option. Thanks to that, bugs and other
> regressions are subsequently easier to catch.
> 
> Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>

Reviewed-by: Laurentiu Palcu <laurentiu.palcu@xxxxxxxxxxx>
Tested-by: Laurentiu Palcu <laurentiu.palcu@xxxxxxxxxxx>

Thanks,
Laurentiu

> ---
> Cc: Laurentiu Palcu <laurentiu.palcu@xxxxxxxxxxx>
> Cc: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
> Cc: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
> Cc: Shawn Guo <shawnguo@xxxxxxxxxx>
> Cc: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
> Cc: Pengutronix Kernel Team <kernel@xxxxxxxxxxxxxx>
> Cc: Fabio Estevam <festevam@xxxxxxxxx>
> Cc: NXP Linux Team <linux-imx@xxxxxxx>
> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> ---
>  drivers/gpu/drm/imx/dcss/dcss-dev.c | 17 +++++++++--------
>  drivers/gpu/drm/imx/dcss/dcss-dev.h |  7 +++----
>  drivers/gpu/drm/imx/dcss/dcss-drv.c |  8 +-------
>  3 files changed, 13 insertions(+), 19 deletions(-)
> 
> diff --git a/drivers/gpu/drm/imx/dcss/dcss-dev.c b/drivers/gpu/drm/imx/dcss/dcss-dev.c
> index 3f5750cc2673..66d9233ffb98 100644
> --- a/drivers/gpu/drm/imx/dcss/dcss-dev.c
> +++ b/drivers/gpu/drm/imx/dcss/dcss-dev.c
> @@ -249,8 +249,7 @@ void dcss_dev_destroy(struct dcss_dev *dcss)
>  	kfree(dcss);
>  }
>  
> -#ifdef CONFIG_PM_SLEEP
> -int dcss_dev_suspend(struct device *dev)
> +static int dcss_dev_suspend(struct device *dev)
>  {
>  	struct dcss_dev *dcss = dcss_drv_dev_to_dcss(dev);
>  	struct drm_device *ddev = dcss_drv_dev_to_drm(dev);
> @@ -273,7 +272,7 @@ int dcss_dev_suspend(struct device *dev)
>  	return 0;
>  }
>  
> -int dcss_dev_resume(struct device *dev)
> +static int dcss_dev_resume(struct device *dev)
>  {
>  	struct dcss_dev *dcss = dcss_drv_dev_to_dcss(dev);
>  	struct drm_device *ddev = dcss_drv_dev_to_drm(dev);
> @@ -296,10 +295,8 @@ int dcss_dev_resume(struct device *dev)
>  
>  	return 0;
>  }
> -#endif /* CONFIG_PM_SLEEP */
>  
> -#ifdef CONFIG_PM
> -int dcss_dev_runtime_suspend(struct device *dev)
> +static int dcss_dev_runtime_suspend(struct device *dev)
>  {
>  	struct dcss_dev *dcss = dcss_drv_dev_to_dcss(dev);
>  	int ret;
> @@ -313,7 +310,7 @@ int dcss_dev_runtime_suspend(struct device *dev)
>  	return 0;
>  }
>  
> -int dcss_dev_runtime_resume(struct device *dev)
> +static int dcss_dev_runtime_resume(struct device *dev)
>  {
>  	struct dcss_dev *dcss = dcss_drv_dev_to_dcss(dev);
>  
> @@ -325,4 +322,8 @@ int dcss_dev_runtime_resume(struct device *dev)
>  
>  	return 0;
>  }
> -#endif /* CONFIG_PM */
> +
> +EXPORT_GPL_DEV_PM_OPS(dcss_dev_pm_ops) = {
> +	RUNTIME_PM_OPS(dcss_dev_runtime_suspend, dcss_dev_runtime_resume, NULL)
> +	SYSTEM_SLEEP_PM_OPS(dcss_dev_suspend, dcss_dev_resume)
> +};
> diff --git a/drivers/gpu/drm/imx/dcss/dcss-dev.h b/drivers/gpu/drm/imx/dcss/dcss-dev.h
> index 1e582270c6ea..f27b87c09599 100644
> --- a/drivers/gpu/drm/imx/dcss/dcss-dev.h
> +++ b/drivers/gpu/drm/imx/dcss/dcss-dev.h
> @@ -9,6 +9,7 @@
>  #include <drm/drm_fourcc.h>
>  #include <drm/drm_plane.h>
>  #include <linux/io.h>
> +#include <linux/pm.h>
>  #include <video/videomode.h>
>  
>  #define SET			0x04
> @@ -95,13 +96,11 @@ struct dcss_dev *dcss_drv_dev_to_dcss(struct device *dev);
>  struct drm_device *dcss_drv_dev_to_drm(struct device *dev);
>  struct dcss_dev *dcss_dev_create(struct device *dev, bool hdmi_output);
>  void dcss_dev_destroy(struct dcss_dev *dcss);
> -int dcss_dev_runtime_suspend(struct device *dev);
> -int dcss_dev_runtime_resume(struct device *dev);
> -int dcss_dev_suspend(struct device *dev);
> -int dcss_dev_resume(struct device *dev);
>  void dcss_enable_dtg_and_ss(struct dcss_dev *dcss);
>  void dcss_disable_dtg_and_ss(struct dcss_dev *dcss);
>  
> +extern const struct dev_pm_ops dcss_dev_pm_ops;
> +
>  /* BLKCTL */
>  int dcss_blkctl_init(struct dcss_dev *dcss, unsigned long blkctl_base);
>  void dcss_blkctl_cfg(struct dcss_blkctl *blkctl);
> diff --git a/drivers/gpu/drm/imx/dcss/dcss-drv.c b/drivers/gpu/drm/imx/dcss/dcss-drv.c
> index 1c70f70247f6..431510bd811b 100644
> --- a/drivers/gpu/drm/imx/dcss/dcss-drv.c
> +++ b/drivers/gpu/drm/imx/dcss/dcss-drv.c
> @@ -117,19 +117,13 @@ static const struct of_device_id dcss_of_match[] = {
>  
>  MODULE_DEVICE_TABLE(of, dcss_of_match);
>  
> -static const struct dev_pm_ops dcss_dev_pm = {
> -	SET_SYSTEM_SLEEP_PM_OPS(dcss_dev_suspend, dcss_dev_resume)
> -	SET_RUNTIME_PM_OPS(dcss_dev_runtime_suspend,
> -			   dcss_dev_runtime_resume, NULL)
> -};
> -
>  static struct platform_driver dcss_platform_driver = {
>  	.probe	= dcss_drv_platform_probe,
>  	.remove	= dcss_drv_platform_remove,
>  	.driver	= {
>  		.name = "imx-dcss",
>  		.of_match_table	= dcss_of_match,
> -		.pm = &dcss_dev_pm,
> +		.pm = pm_ptr(&dcss_dev_pm_ops),
>  	},
>  };
>  
> -- 
> 2.35.1
>