[PATCH] drm: rcar-du: Use dev_err_probe() helper

[Laurent Pinchart]

Hello,

On Wed, Dec 08, 2021 at 11:57:21AM +0000, Kieran Bingham wrote:
> Quoting Geert Uytterhoeven (2021-12-08 10:30:53)
> > Use the dev_err_probe() helper, instead of open-coding the same
> > operation.
> > 
> > Signed-off-by: Geert Uytterhoeven <geert+renesas at glider.be>
> > ---
> >  drivers/gpu/drm/rcar-du/rcar_du_drv.c | 5 ++---
> >  1 file changed, 2 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/rcar-du/rcar_du_drv.c b/drivers/gpu/drm/rcar-du/rcar_du_drv.c
> > index 5612a9e7a9056cf7..86eeda769e2ebd10 100644
> > --- a/drivers/gpu/drm/rcar-du/rcar_du_drv.c
> > +++ b/drivers/gpu/drm/rcar-du/rcar_du_drv.c
> > @@ -661,9 +661,8 @@ static int rcar_du_probe(struct platform_device *pdev)
> >         /* DRM/KMS objects */
> >         ret = rcar_du_modeset_init(rcdu);
> >         if (ret < 0) {
> > -               if (ret != -EPROBE_DEFER)
> > -                       dev_err(&pdev->dev,
> > -                               "failed to initialize DRM/KMS (%d)\n", ret);
> > +               dev_err_probe(&pdev->dev, ret,
> > +                             "failed to initialize DRM/KMS\n");
> 
> I've just learned that dev_err_probe() sets a 'reason' for the deferral.
> Seems like a nice feature when exploring devices that are still waiting
> to probe. Is the message still appropriate enough in that case?

It's a very generic message, so it's not ideal. One issue is that
dev_err_probe() replaces any currently stored probe deferral reason
message, which means that we'll override any message previously set. We
don't set any message now, but we should (in rcar_du_encoder_init(),
there are two main code paths where -EPROBE_DEFER is expected), so this
patch would then get in the way I'm afraid.

> I think it's probably fine, so
> 
> Reviewed-by: Kieran Bingham <kieran.bingham+renesas at ideasonboard.com>
> 
> >                 goto error;
> >         }
> >  

-- 
Regards,

Laurent Pinchart