Re: [PATCH 1/1] smiapp: Implement power-on and power-off sequences without runtime PM

[Arnd Bergmann <arnd@arndb.de>]

On Friday, November 18, 2016 3:50:16 PM CET Sakari Ailus wrote:
> Power on the sensor when the module is loaded and power it off when it is
> removed.
> 
> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> ---
> Hi Arnd and others,
> 
> The patch is tested with CONFIG_PM set, as the system does I was testing
> on did not boot with CONFIG_PM disabled. I'm not really too worried about
> this though, the patch is very simple.
> 


>  static struct smiapp_hwconfig *smiapp_get_hwconfig(struct device *dev)
>  {
>  	struct smiapp_hwconfig *hwcfg;
> @@ -2915,7 +2906,11 @@ static int smiapp_probe(struct i2c_client *client,
>  
>  	pm_runtime_enable(&client->dev);
>  
> +#ifdef CONFIG_PM
>  	rval = pm_runtime_get_sync(&client->dev);
> +#else
> +	rval = smiapp_power_on(&client->dev);
> +#endif
>  	if (rval < 0) {
>  		rval = -ENODEV;
>  		goto out_power_off;

I would suggest writing this as

	if (IS_ENABLED(CONFIG_PM))
		rval = pm_runtime_get_sync(&client->dev);
	else
		rval = smiapp_power_on(&client->dev);

though that is a purely cosmetic change.

I think you are missing one other warning: with CONFIG_PM=y and
CONFIG_PM_SLEEP=n, the smiapp_suspend/smiapp_resume functions
are now unused and need to be marked as __maybe_unused.

	Arnd