[PATCH v2] drm/exynos: fix error return code exynos_drm_load()

[Wei Yongjun]

From: Wei Yongjun <yongjun_wei at trendmicro.com.cn>

Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.
Change function exynos_plane_init() to return ERR_PTR(), so
the caller can use the error code from it.

Signed-off-by: Wei Yongjun <yongjun_wei at trendmicro.com.cn>
---
v1 -> v2: change exynos_plane_init() to return ERR_PTR().
---
 drivers/gpu/drm/exynos/exynos_drm_plane.c | 4 ++--
 drivers/gpu/drm/exynos/exynos_drm_crtc.c  | 4 ++--
 drivers/gpu/drm/exynos/exynos_drm_drv.c   | 4 +++-
 3 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_plane.c b/drivers/gpu/drm/exynos/exynos_drm_plane.c
index 83efc66..2770f4b 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_plane.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_plane.c
@@ -282,7 +282,7 @@ struct drm_plane *exynos_plane_init(struct drm_device *dev,
 	exynos_plane = kzalloc(sizeof(struct exynos_plane), GFP_KERNEL);
 	if (!exynos_plane) {
 		DRM_ERROR("failed to allocate plane\n");
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 	}
 
 	err = drm_plane_init(dev, &exynos_plane->base, possible_crtcs,
@@ -291,7 +291,7 @@ struct drm_plane *exynos_plane_init(struct drm_device *dev,
 	if (err) {
 		DRM_ERROR("failed to initialize plane\n");
 		kfree(exynos_plane);
-		return NULL;
+		return ERR_PTR(err);
 	}
 
 	if (priv)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_crtc.c b/drivers/gpu/drm/exynos/exynos_drm_crtc.c
index e8894bc..21d0675 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_crtc.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_crtc.c
@@ -345,9 +345,9 @@ int exynos_drm_crtc_create(struct drm_device *dev, unsigned int nr)
 	exynos_crtc->pipe = nr;
 	exynos_crtc->dpms = DRM_MODE_DPMS_OFF;
 	exynos_crtc->plane = exynos_plane_init(dev, 1 << nr, true);
-	if (!exynos_crtc->plane) {
+	if (IS_ERR(exynos_crtc->plane)) {
 		kfree(exynos_crtc);
-		return -ENOMEM;
+		return PTR_ERR(exynos_crtc->plane);
 	}
 
 	crtc = &exynos_crtc->drm_crtc;

diff --git a/drivers/gpu/drm/exynos/exynos_drm_drv.c b/drivers/gpu/drm/exynos/exynos_drm_drv.c
index ba6d995..44f1d50 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_drv.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_drv.c
@@ -91,8 +91,10 @@ static int exynos_drm_load(struct drm_device *dev, unsigned long flags)
 		unsigned int possible_crtcs = (1 << MAX_CRTC) - 1;
 
 		plane = exynos_plane_init(dev, possible_crtcs, false);
-		if (!plane)
+		if (IS_ERR(plane) {
+			ret = PTR_ERR(plane);
 			goto err_release_iommu_mapping;
+		}
 	}
 
 	ret = drm_vblank_init(dev, MAX_CRTC);