(EXT) Re: (EXT) [PATCH 10/55] media: rkisp1: cap: Print debug message on failed link validation

[Alexander Stein]

Hello Laurent,

Am Donnerstag, 16. Juni 2022, 09:41:22 CEST schrieb Laurent Pinchart:
> Hi Alexander,
> 
> On Thu, Jun 16, 2022 at 09:32:17AM +0200, Alexander Stein wrote:
> > Am Dienstag, 14. Juni 2022, 21:10:42 CEST schrieb Paul Elder:
> > > From: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> > > 
> > > When a link validation failure occurs, print a debug message to help
> > > diagnosing the cause.
> > > 
> > > Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> > > ---
> > > 
> > >  .../media/platform/rockchip/rkisp1/rkisp1-capture.c    | 10 +++++++++-
> > >  1 file changed, 9 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/media/platform/rockchip/rkisp1/rkisp1-capture.c
> > > b/drivers/media/platform/rockchip/rkisp1/rkisp1-capture.c index
> > > 94819e6c23e2..94a0d787a312 100644
> > > --- a/drivers/media/platform/rockchip/rkisp1/rkisp1-capture.c
> > > +++ b/drivers/media/platform/rockchip/rkisp1/rkisp1-capture.c
> > > @@ -1294,8 +1294,16 @@ static int rkisp1_capture_link_validate(struct
> > > media_link *link)
> > > 
> > >  	if (sd_fmt.format.height != cap->pix.fmt.height ||
> > >  	
> > >  	    sd_fmt.format.width != cap->pix.fmt.width ||
> > > 
> > > -	    sd_fmt.format.code != fmt->mbus)
> > > +	    sd_fmt.format.code != fmt->mbus) {
> > > +		dev_dbg(cap->rkisp1->dev,
> > 
> > I wonder if a dev_warn is more suitable here.
> 
> I usually recommend dev_dbg() for conditions that are triggered directly
> by userspace, to avoid giving unpriviledged applications an(other) easy
> way to flood the kernel log.

Agreed, this is a sensible thing to do. I'm still wondering if this 
information might be missing, when having a build without DYNAMIC_DEBUG.
Nevertheless I'm fine to start with this debug output at least.

Regards,
Alexander

> > > +			"link '%s':%u -> '%s':%u not valid: 0x%04x/ 
%ux%u != 0x%04x/%ux%u",
> > > +			link->source->entity->name, link->source-
>index,
> > > +			link->sink->entity->name, link->sink->index,
> > > +			sd_fmt.format.code, sd_fmt.format.width,
> > > +			sd_fmt.format.height, fmt->mbus, cap-
>pix.fmt.width,
> > > +			cap->pix.fmt.height);
> > > 
> > >  		return -EPIPE;
> > > 
> > > +	}
> > > 
> > >  	return 0;
> > >  
> > >  }