Re: [PATCH][next] drm/rockchip: Remove redundant assignment of pointer connector

From: Heiko Stübner
Date: Wed Sep 22 2021 - 12:45:35 EST


Hi Alex,

Am Mittwoch, 22. September 2021, 18:35:38 CEST schrieb Alex Bee:
> Hi Colin,
> Am 22.09.21 um 13:24 schrieb Colin King:
> > From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> >
> > The pointer connector is being assigned a value that is never
> > read, it is being updated immediately afterwards. The assignment
> > is redundant and can be removed.
>
> The pointer to the connector is used in rockchip_rgb_fini for
> drm_connector_cleanup.
> It's pretty much the same for the encoder, btw.

I think the issue is more the two lines

connector = &rgb->connector;
connector = drm_bridge_connector_init(rgb->drm_dev, encoder);

hence the connector = &rgb->connector being overwritten immediately after

Now that I look at it again, the whole approach looks strange.
drm_bridge_connector_init() creates the connector structure and
returns a pointer to it.

So the first line below sets the connector pointer to point to the
&rgb->connector element and the second line then set a completely
different address into it.

So the connector element in rockchip_lvds and rockchip_rgb should actually
become a pointer itself to hold the connector element returned from
drm_bridge_connector_init() .


Heiko

>
> Regards,
>
> Alex
> >
> > Addresses-Coverity: ("Unused value")
> > Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> > ---
> > drivers/gpu/drm/rockchip/rockchip_rgb.c | 1 -
> > 1 file changed, 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/rockchip/rockchip_rgb.c b/drivers/gpu/drm/rockchip/rockchip_rgb.c
> > index 09be9678f2bd..18fb84068a64 100644
> > --- a/drivers/gpu/drm/rockchip/rockchip_rgb.c
> > +++ b/drivers/gpu/drm/rockchip/rockchip_rgb.c
> > @@ -150,7 +150,6 @@ struct rockchip_rgb *rockchip_rgb_init(struct device *dev,
> > if (ret)
> > goto err_free_encoder;
> >
> > - connector = &rgb->connector;
> > connector = drm_bridge_connector_init(rgb->drm_dev, encoder);
> > if (IS_ERR(connector)) {
> > DRM_DEV_ERROR(drm_dev->dev,
> >
>
>