drm/mgag200: Switch I2C code to managed cleanup

Store the I2C state within struct mga_device and switch I2C to
managed release. Simplifies the related code and lets us remove
mga_connector_destroy().
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Jocelyn Falempe <jfalempe@redhat.com>
Tested-by: Jocelyn Falempe <jfalempe@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220516134343.6085-5-tzimmermann@suse.de

drivers/gpu/drm/mgag200/mgag200_drv.h

@@ -179,7 +179,6 @@ struct mga_i2c_chan {
 
 struct mga_connector {
 	struct drm_connector base;
-	struct mga_i2c_chan *i2c;
 };
 
 struct mga_mc {
@@ -239,6 +238,7 @@ struct mga_device {
 
 	struct mga_connector connector;
 	struct mgag200_pll pixpll;
+	struct mga_i2c_chan i2c;
 	struct drm_simple_display_pipe display_pipe;
 };
 
@@ -251,8 +251,7 @@ static inline struct mga_device *to_mga_device(struct drm_device *dev)
 int mgag200_modeset_init(struct mga_device *mdev);
 
 				/* mgag200_i2c.c */
-struct mga_i2c_chan *mgag200_i2c_create(struct drm_device *dev);
-void mgag200_i2c_destroy(struct mga_i2c_chan *i2c);
+int mgag200_i2c_init(struct mga_device *mdev, struct mga_i2c_chan *i2c);
 
 				/* mgag200_mm.c */
 int mgag200_mm_init(struct mga_device *mdev);

drivers/gpu/drm/mgag200/mgag200_i2c.c

@@ -86,10 +86,16 @@ static int mga_gpio_getscl(void *data)
 	return (mga_i2c_read_gpio(mdev) & i2c->clock) ? 1 : 0;
 }
 
-struct mga_i2c_chan *mgag200_i2c_create(struct drm_device *dev)
+static void mgag200_i2c_release(void *res)
 {
-	struct mga_device *mdev = to_mga_device(dev);
-	struct mga_i2c_chan *i2c;
+	struct mga_i2c_chan *i2c = res;
+
+	i2c_del_adapter(&i2c->adapter);
+}
+
+int mgag200_i2c_init(struct mga_device *mdev, struct mga_i2c_chan *i2c)
+{
+	struct drm_device *dev = &mdev->base;
 	int ret;
 	int data, clock;
 
@@ -118,10 +124,6 @@ struct mga_i2c_chan *mgag200_i2c_create(struct drm_device *dev)
 		break;
 	}
 
-	i2c = kzalloc(sizeof(struct mga_i2c_chan), GFP_KERNEL);
-	if (!i2c)
-		return ERR_PTR(-ENOMEM);
-
 	i2c->data = data;
 	i2c->clock = clock;
 	i2c->adapter.owner = THIS_MODULE;
@@ -143,20 +145,7 @@ struct mga_i2c_chan *mgag200_i2c_create(struct drm_device *dev)
 
 	ret = i2c_bit_add_bus(&i2c->adapter);
 	if (ret)
-		goto err_kfree;
+		return ret;
 
-	return i2c;
-
-err_kfree:
-	kfree(i2c);
-	return ERR_PTR(ret);
-}
-
-void mgag200_i2c_destroy(struct mga_i2c_chan *i2c)
-{
-	if (!i2c)
-		return;
-	i2c_del_adapter(&i2c->adapter);
-	kfree(i2c);
+	return devm_add_action_or_reset(dev->dev, mgag200_i2c_release, i2c);
 }
-

drivers/gpu/drm/mgag200/mgag200_mode.c

@@ -811,13 +811,6 @@ static enum drm_mode_status mga_vga_mode_valid(struct drm_connector *connector,
 	return MODE_OK;
 }
 
-static void mga_connector_destroy(struct drm_connector *connector)
-{
-	struct mga_connector *mga_connector = to_mga_connector(connector);
-	mgag200_i2c_destroy(mga_connector->i2c);
-	drm_connector_cleanup(connector);
-}
-
 static const struct drm_connector_helper_funcs mga_vga_connector_helper_funcs = {
 	.get_modes  = mgag200_vga_connector_helper_get_modes,
 	.mode_valid = mga_vga_mode_valid,
@@ -826,7 +819,7 @@ static const struct drm_connector_helper_funcs mga_vga_connector_helper_funcs =
 static const struct drm_connector_funcs mga_vga_connector_funcs = {
 	.reset                  = drm_atomic_helper_connector_reset,
 	.fill_modes             = drm_helper_probe_single_connector_modes,
-	.destroy                = mga_connector_destroy,
+	.destroy                = drm_connector_cleanup,
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 	.atomic_destroy_state   = drm_atomic_helper_connector_destroy_state,
 };
@@ -836,12 +829,11 @@ static int mgag200_vga_connector_init(struct mga_device *mdev)
 	struct drm_device *dev = &mdev->base;
 	struct mga_connector *mconnector = &mdev->connector;
 	struct drm_connector *connector = &mconnector->base;
-	struct mga_i2c_chan *i2c;
+	struct mga_i2c_chan *i2c = &mdev->i2c;
 	int ret;
 
-	i2c = mgag200_i2c_create(dev);
-	if (IS_ERR(i2c)) {
-		ret = PTR_ERR(i2c)
+	ret = mgag200_i2c_init(mdev, i2c);
+	if (ret) {
 		drm_err(dev, "failed to add DDC bus: %d\n", ret);
 		return ret;
 	}
@@ -851,16 +843,10 @@ static int mgag200_vga_connector_init(struct mga_device *mdev)
 					  DRM_MODE_CONNECTOR_VGA,
 					  &i2c->adapter);
 	if (ret)
-		goto err_mgag200_i2c_destroy;
+		return ret;
 	drm_connector_helper_add(connector, &mga_vga_connector_helper_funcs);
 
-	mconnector->i2c = i2c;
-
 	return 0;
-
-err_mgag200_i2c_destroy:
-	mgag200_i2c_destroy(i2c);
-	return ret;
 }
 
 /*