[PATCH v3 4/5] drm/ast: Fail probing if DCC channel could not be initialized

[Thomas Zimmermann <tzimmermann@xxxxxxx>]

Expect the hardware to provide a DDC channel. Fail probing if its
initialization fails.

Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
Reviewed-by: Patrik Jakobsson <patrik.r.jakobsson@xxxxxxxxx>
---
 drivers/gpu/drm/ast/ast_drv.h  |  2 --
 drivers/gpu/drm/ast/ast_i2c.c  |  7 ++++---
 drivers/gpu/drm/ast/ast_mode.c | 38 ++++++++++++++++------------------
 3 files changed, 22 insertions(+), 25 deletions(-)

diff --git a/drivers/gpu/drm/ast/ast_drv.h b/drivers/gpu/drm/ast/ast_drv.h
index a34db4380f68..bc01090d0ad1 100644
--- a/drivers/gpu/drm/ast/ast_drv.h
+++ b/drivers/gpu/drm/ast/ast_drv.h
@@ -137,7 +137,6 @@ struct ast_i2c_chan {
 
 struct ast_vga_connector {
 	struct drm_connector base;
-	struct ast_i2c_chan *i2c;
 };
 
 static inline struct ast_vga_connector *
@@ -148,7 +147,6 @@ to_ast_vga_connector(struct drm_connector *connector)
 
 struct ast_sil164_connector {
 	struct drm_connector base;
-	struct ast_i2c_chan *i2c;
 };
 
 static inline struct ast_sil164_connector *
diff --git a/drivers/gpu/drm/ast/ast_i2c.c b/drivers/gpu/drm/ast/ast_i2c.c
index 93e91c36d649..1d039ff1396e 100644
--- a/drivers/gpu/drm/ast/ast_i2c.c
+++ b/drivers/gpu/drm/ast/ast_i2c.c
@@ -117,7 +117,7 @@ struct ast_i2c_chan *ast_i2c_create(struct drm_device *dev)
 
 	i2c = kzalloc(sizeof(struct ast_i2c_chan), GFP_KERNEL);
 	if (!i2c)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	i2c->adapter.owner = THIS_MODULE;
 	i2c->adapter.class = I2C_CLASS_DDC;
@@ -143,10 +143,11 @@ struct ast_i2c_chan *ast_i2c_create(struct drm_device *dev)
 
 	ret = drmm_add_action_or_reset(dev, ast_i2c_release, i2c);
 	if (ret)
-		return NULL;
+		return ERR_PTR(ret);
+
 	return i2c;
 
 out_kfree:
 	kfree(i2c);
-	return NULL;
+	return ERR_PTR(ret);
 }
diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
index 582f278436ea..364035d22463 100644
--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -1334,19 +1334,18 @@ static int ast_vga_connector_init(struct drm_device *dev,
 				  struct ast_vga_connector *ast_vga_connector)
 {
 	struct drm_connector *connector = &ast_vga_connector->base;
+	struct ast_i2c_chan *i2c;
 	int ret;
 
-	ast_vga_connector->i2c = ast_i2c_create(dev);
-	if (!ast_vga_connector->i2c)
-		drm_err(dev, "failed to add ddc bus for connector\n");
+	i2c = ast_i2c_create(dev);
+	if (IS_ERR(i2c)) {
+		ret = PTR_ERR(i2c);
+		drm_err(dev, "failed to add ddc bus for connector; ret=%d\n", ret);
+		return ret;
+	}
 
-	if (ast_vga_connector->i2c)
-		ret = drm_connector_init_with_ddc(dev, connector, &ast_vga_connector_funcs,
-						  DRM_MODE_CONNECTOR_VGA,
-						  &ast_vga_connector->i2c->adapter);
-	else
-		ret = drm_connector_init(dev, connector, &ast_vga_connector_funcs,
-					 DRM_MODE_CONNECTOR_VGA);
+	ret = drm_connector_init_with_ddc(dev, connector, &ast_vga_connector_funcs,
+					  DRM_MODE_CONNECTOR_VGA, &i2c->adapter);
 	if (ret)
 		return ret;
 
@@ -1406,19 +1405,18 @@ static int ast_sil164_connector_init(struct drm_device *dev,
 				     struct ast_sil164_connector *ast_sil164_connector)
 {
 	struct drm_connector *connector = &ast_sil164_connector->base;
+	struct ast_i2c_chan *i2c;
 	int ret;
 
-	ast_sil164_connector->i2c = ast_i2c_create(dev);
-	if (!ast_sil164_connector->i2c)
-		drm_err(dev, "failed to add ddc bus for connector\n");
+	i2c = ast_i2c_create(dev);
+	if (IS_ERR(i2c)) {
+		ret = PTR_ERR(i2c);
+		drm_err(dev, "failed to add ddc bus for connector; ret=%d\n", ret);
+		return ret;
+	}
 
-	if (ast_sil164_connector->i2c)
-		ret = drm_connector_init_with_ddc(dev, connector, &ast_sil164_connector_funcs,
-						  DRM_MODE_CONNECTOR_DVII,
-						  &ast_sil164_connector->i2c->adapter);
-	else
-		ret = drm_connector_init(dev, connector, &ast_sil164_connector_funcs,
-					 DRM_MODE_CONNECTOR_DVII);
+	ret = drm_connector_init_with_ddc(dev, connector, &ast_sil164_connector_funcs,
+					  DRM_MODE_CONNECTOR_DVII, &i2c->adapter);
 	if (ret)
 		return ret;
 
-- 
2.36.1