drm/i2c: tda998x: mali-dp: hdlcd: refactor connector registration

Connectors shouldn't be registered until the rest of the whole device
is set up, so that consistent state is presented to userspace.

As such, remove the calls to drm_connector_register() and
drm_connector_unregister() from tda998x, as these are now handled by
drm_dev_(un)register() itself.

To work with this change, the mali-dp and hdlcd bind and unbind
sequences have to be reordered, to ensure that the componentised
encoder/connector is bound before drm_dev_register() registers all
connectors. Similarly, the device must be unregistered before the
component is unbound.

Altogether, this allows other drivers using tda998x to be
de-midlayered, and to have less racy initialisation of their components.

Splitting this commit into three (one per driver) isn't possible without
intermediate breakage, so it is all squashed together here.
Suggested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Brian Starkey <brian.starkey@arm.com>
Reviewed-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

drivers/gpu/drm/arm/hdlcd_drv.c

@@ -337,14 +337,10 @@ static int hdlcd_drm_bind(struct device *dev)
 	if (ret)
 		goto err_free;
 
-	ret = drm_dev_register(drm, 0);
-	if (ret)
-		goto err_unload;
-
 	ret = component_bind_all(dev, drm);
 	if (ret) {
 		DRM_ERROR("Failed to bind all components\n");
-		goto err_unregister;
+		goto err_unload;
 	}
 
 	ret = pm_runtime_set_active(dev);
@@ -371,8 +367,17 @@ static int hdlcd_drm_bind(struct device *dev)
 		goto err_fbdev;
 	}
 
+	ret = drm_dev_register(drm, 0);
+	if (ret)
+		goto err_register;
+
 	return 0;
 
+err_register:
+	if (hdlcd->fbdev) {
+		drm_fbdev_cma_fini(hdlcd->fbdev);
+		hdlcd->fbdev = NULL;
+	}
 err_fbdev:
 	drm_kms_helper_poll_fini(drm);
 	drm_mode_config_cleanup(drm);
@@ -381,8 +386,6 @@ static int hdlcd_drm_bind(struct device *dev)
 	pm_runtime_disable(drm->dev);
 err_pm_active:
 	component_unbind_all(dev, drm);
-err_unregister:
-	drm_dev_unregister(drm);
 err_unload:
 	drm_irq_uninstall(drm);
 	of_reserved_mem_device_release(drm->dev);
@@ -398,6 +401,7 @@ static void hdlcd_drm_unbind(struct device *dev)
 	struct drm_device *drm = dev_get_drvdata(dev);
 	struct hdlcd_drm_private *hdlcd = drm->dev_private;
 
+	drm_dev_unregister(drm);
 	if (hdlcd->fbdev) {
 		drm_fbdev_cma_fini(hdlcd->fbdev);
 		hdlcd->fbdev = NULL;
@@ -411,7 +415,6 @@ static void hdlcd_drm_unbind(struct device *dev)
 	pm_runtime_disable(drm->dev);
 	of_reserved_mem_device_release(drm->dev);
 	drm_mode_config_cleanup(drm);
-	drm_dev_unregister(drm);
 	drm_dev_unref(drm);
 	drm->dev_private = NULL;
 	dev_set_drvdata(dev, NULL);

drivers/gpu/drm/arm/malidp_drv.c

@@ -354,10 +354,6 @@ static int malidp_bind(struct device *dev)
 	if (ret < 0)
 		goto init_fail;
 
-	ret = drm_dev_register(drm, 0);
-	if (ret)
-		goto register_fail;
-
 	/* Set the CRTC's port so that the encoder component can find it */
 	ep = of_graph_get_next_endpoint(dev->of_node, NULL);
 	if (!ep) {
@@ -394,8 +390,18 @@ static int malidp_bind(struct device *dev)
 	}
 
 	drm_kms_helper_poll_init(drm);
+
+	ret = drm_dev_register(drm, 0);
+	if (ret)
+		goto register_fail;
+
 	return 0;
 
+register_fail:
+	if (malidp->fbdev) {
+		drm_fbdev_cma_fini(malidp->fbdev);
+		malidp->fbdev = NULL;
+	}
 fbdev_fail:
 	drm_vblank_cleanup(drm);
 vblank_fail:
@@ -407,8 +413,6 @@ static int malidp_bind(struct device *dev)
 	of_node_put(malidp->crtc.port);
 	malidp->crtc.port = NULL;
 port_fail:
-	drm_dev_unregister(drm);
-register_fail:
 	malidp_de_planes_destroy(drm);
 	drm_mode_config_cleanup(drm);
 init_fail:
@@ -431,6 +435,7 @@ static void malidp_unbind(struct device *dev)
 	struct malidp_drm *malidp = drm->dev_private;
 	struct malidp_hw_device *hwdev = malidp->dev;
 
+	drm_dev_unregister(drm);
 	if (malidp->fbdev) {
 		drm_fbdev_cma_fini(malidp->fbdev);
 		malidp->fbdev = NULL;
@@ -442,7 +447,6 @@ static void malidp_unbind(struct device *dev)
 	component_unbind_all(dev, drm);
 	of_node_put(malidp->crtc.port);
 	malidp->crtc.port = NULL;
-	drm_dev_unregister(drm);
 	malidp_de_planes_destroy(drm);
 	drm_mode_config_cleanup(drm);
 	drm->dev_private = NULL;

drivers/gpu/drm/i2c/tda998x_drv.c

@@ -1369,7 +1369,6 @@ const struct drm_connector_helper_funcs tda998x_connector_helper_funcs = {
 
 static void tda998x_connector_destroy(struct drm_connector *connector)
 {
-	drm_connector_unregister(connector);
 	drm_connector_cleanup(connector);
 }
 
@@ -1441,16 +1440,10 @@ static int tda998x_bind(struct device *dev, struct device *master, void *data)
 	if (ret)
 		goto err_connector;
 
-	ret = drm_connector_register(&priv->connector);
-	if (ret)
-		goto err_sysfs;
-
 	drm_mode_connector_attach_encoder(&priv->connector, &priv->encoder);
 
 	return 0;
 
-err_sysfs:
-	drm_connector_cleanup(&priv->connector);
 err_connector:
 	drm_encoder_cleanup(&priv->encoder);
 err_encoder:
@@ -1463,7 +1456,6 @@ static void tda998x_unbind(struct device *dev, struct device *master,
 {
 	struct tda998x_priv *priv = dev_get_drvdata(dev);
 
-	drm_connector_unregister(&priv->connector);
 	drm_connector_cleanup(&priv->connector);
 	drm_encoder_cleanup(&priv->encoder);
 	tda998x_destroy(priv);