Re: [PATCH 1/1] checkpatch: Deprecate V4L2 pipeline power management code

[Sakari Ailus]

Hi Joe,

On Tue, Jul 14, 2026 at 03:28:13AM -0700, Joe Perches wrote:
> On Mon, 2026-07-13 at 19:13 +0300, Sakari Ailus wrote:
> > The V4L2 pipeline power management code, in particular
> > v4l2_pipeline_link_notify(), v4l2_pipeline_pm_get() and
> > v4l2_pipeline_pm_put() are deprecated and shall not be used in new code.
> > 
> > The drivers need to use the Runtime PM instead.
> 
> Nack. Say that in the error output.
> 
> Given this patch, checkpatch's message would be something like
> 
> "Deprecated use of 'v4l2_pipeline_pm_get', prefer '' instead"

That's even technically correct: these functions serve no useful purpose
anymore, all new drivers effectively use Runtime PM anyway.

> 
> > diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> []
> > @@ -879,6 +879,9 @@ our %deprecated_apis = (
> >  	"DEFINE_IDR"				=> "DEFINE_XARRAY",
> >  	"idr_init"				=> "xa_init",
> >  	"idr_init_base"				=> "xa_init_flags",
> > +	"v4l2_pipeline_link_notify"		=> "",
> > +	"v4l2_pipeline_pm_get"			=> "",
> > +	"v4l2_pipeline_pm_put"			=> "",
> 
> Add something like "v4l2 runtime power management API" instead
> At least point out what that is.

How about simply "Runtime PM"?

> 
> And in today's '-next' there's seems to be no indication in
> documentation or code these calls are deprecated.

The deprecation notes were introduced in commits
b97213a41140b87f48865ba594a1f4b5c5566631 and
4ec2caab775606c4bf9d0f026f8942a0b33e2255, the latter of which was merged in
2024.

-- 
Regards,

Sakari Ailus