Re: [PATCH] PM: runtime: Add kerneldoc comments to multiple helpers

[Sakari Ailus]

Hi Rafael,

Thanks for the patch.

On Fri, Jul 31, 2020 at 07:03:26PM +0200, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> 
> Add kerneldoc comments to multiple PM-runtime helper functions
> defined as static inline wrappers around lower-level routines to
> provide quick reference decumentation of their behavior.
> 
> Some of them are similar to each other with subtle differences only
> and the behavior of some of them may appear as counter-intuitive, so
> clarify all that to avoid confusion.
> 
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> ---
>  include/linux/pm_runtime.h |  246 +++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 246 insertions(+)
> 
> Index: linux-pm/include/linux/pm_runtime.h
> ===================================================================
> --- linux-pm.orig/include/linux/pm_runtime.h
> +++ linux-pm/include/linux/pm_runtime.h
> @@ -60,58 +60,151 @@ extern void pm_runtime_put_suppliers(str
>  extern void pm_runtime_new_link(struct device *dev);
>  extern void pm_runtime_drop_link(struct device *dev);
>  
> +/**
> + * pm_runtime_get_if_in_use - Conditionally bump up runtime PM usage counter.
> + * @dev: Target device.
> + *
> + * Increment the runtime PM usage counter of @dev if its runtime PM status is
> + * %RPM_ACTIVE and its runtime PM usage counter is greater than 0.

The implementation of the non-runtime PM variants (used when CONFIG_PM is
disabled) isn't here but I think it'd be nice if their behaviour was also
documented here. pm_runtime_get_if_in_use() returns -EINVAL if CONFIG_PM is
disabled, for instance.

pm_runtime_disable() is defined here but the documentation in corresponding
pm_runtime_enable() in drivers/base/power/runtime.c is rather terse. It'd
be nice to improve that now (or separately).

-- 
Kind regards,

Sakari Ailus