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@canonical.com

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@canonical.com

---

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,

Hi all,

Am 22.09.21 um 19:31 schrieb Alex Bee:

Hi Heiko,

Am 22.09.21 um 18:45 schrieb Heiko Stübner:

...

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@canonical.com

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.

Totally agreed.

The main reason I was doing it that way, was the way it was done already in rockchip_lvds.c, where the connector was already existent in the struct rockchip_lvds (and was already used in the panel-case - all places where it is used accept pointers also, btw) and is *no* pointer - and is done already this very strange way.

I wanted to re-use it for the bridge-case and didn't want to differ in coding in rockchip-rgb to much.

The only reason I can think of, why it was done that way is, that we might need a pointer to a fully initialized struct drm_connector for some reason (drm_connector_cleanup ?), what we wouldn't have if have just a pointer and something goes wrong before drm_connector_init respectivly drm_bridge_connector_init.

Alex

...

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() .

It turns out, nothing bad happens (i.e. rockchip_rgb_fini, the only place where the connector is also used, isn't called if rockchip_rgb_init fails) - so it will be OK if we make the connector a pointer in struct rockchip_rgb. But we'll need to keep it a "full" struct drm_connector in struct rockchip_lvds, since in case it's a panel  it gets properties assigend before drm_connector_init is called and should for that reason initialized before.

I'll send a patch soon.

Alex

...

Heiko

...

Regards,

Alex

...

Addresses-Coverity: ("Unused value") Signed-off-by: Colin Ian King colin.king@canonical.com

---

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,