drm/rcar-du: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert the rcar-du drm driver from always returning zero in
the remove callback to the void returning variant.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230507162616.1368908-38-u.kleine-koenig@pengutronix.de

drivers/gpu/drm/rcar-du/rcar_cmm.c

@@ -187,11 +187,9 @@ static int rcar_cmm_probe(struct platform_device *pdev)
 	return 0;
 }
 
-static int rcar_cmm_remove(struct platform_device *pdev)
+static void rcar_cmm_remove(struct platform_device *pdev)
 {
 	pm_runtime_disable(&pdev->dev);
-
-	return 0;
 }
 
 static const struct of_device_id rcar_cmm_of_table[] = {
@@ -203,7 +201,7 @@ MODULE_DEVICE_TABLE(of, rcar_cmm_of_table);
 
 static struct platform_driver rcar_cmm_platform_driver = {
 	.probe		= rcar_cmm_probe,
-	.remove		= rcar_cmm_remove,
+	.remove_new	= rcar_cmm_remove,
 	.driver		= {
 		.name	= "rcar-cmm",
 		.of_match_table = rcar_cmm_of_table,

drivers/gpu/drm/rcar-du/rcar_du_drv.c

@@ -685,7 +685,7 @@ static DEFINE_SIMPLE_DEV_PM_OPS(rcar_du_pm_ops,
  * Platform driver
  */
 
-static int rcar_du_remove(struct platform_device *pdev)
+static void rcar_du_remove(struct platform_device *pdev)
 {
 	struct rcar_du_device *rcdu = platform_get_drvdata(pdev);
 	struct drm_device *ddev = &rcdu->ddev;
@@ -694,8 +694,6 @@ static int rcar_du_remove(struct platform_device *pdev)
 	drm_atomic_helper_shutdown(ddev);
 
 	drm_kms_helper_poll_fini(ddev);
-
-	return 0;
 }
 
 static void rcar_du_shutdown(struct platform_device *pdev)
@@ -776,7 +774,7 @@ static int rcar_du_probe(struct platform_device *pdev)
 
 static struct platform_driver rcar_du_platform_driver = {
 	.probe		= rcar_du_probe,
-	.remove		= rcar_du_remove,
+	.remove_new	= rcar_du_remove,
 	.shutdown	= rcar_du_shutdown,
 	.driver		= {
 		.name	= "rcar-du",

drivers/gpu/drm/rcar-du/rcar_dw_hdmi.c

@@ -93,13 +93,11 @@ static int rcar_dw_hdmi_probe(struct platform_device *pdev)
 	return 0;
 }
 
-static int rcar_dw_hdmi_remove(struct platform_device *pdev)
+static void rcar_dw_hdmi_remove(struct platform_device *pdev)
 {
 	struct dw_hdmi *hdmi = platform_get_drvdata(pdev);
 
 	dw_hdmi_remove(hdmi);
-
-	return 0;
 }
 
 static const struct of_device_id rcar_dw_hdmi_of_table[] = {
@@ -110,7 +108,7 @@ MODULE_DEVICE_TABLE(of, rcar_dw_hdmi_of_table);
 
 static struct platform_driver rcar_dw_hdmi_platform_driver = {
 	.probe		= rcar_dw_hdmi_probe,
-	.remove		= rcar_dw_hdmi_remove,
+	.remove_new	= rcar_dw_hdmi_remove,
 	.driver		= {
 		.name	= "rcar-dw-hdmi",
 		.of_match_table = rcar_dw_hdmi_of_table,

drivers/gpu/drm/rcar-du/rcar_lvds.c

@@ -918,15 +918,13 @@ static int rcar_lvds_probe(struct platform_device *pdev)
 	return 0;
 }
 
-static int rcar_lvds_remove(struct platform_device *pdev)
+static void rcar_lvds_remove(struct platform_device *pdev)
 {
 	struct rcar_lvds *lvds = platform_get_drvdata(pdev);
 
 	drm_bridge_remove(&lvds->bridge);
 
 	pm_runtime_disable(&pdev->dev);
-
-	return 0;
 }
 
 static const struct rcar_lvds_device_info rcar_lvds_gen2_info = {
@@ -1020,7 +1018,7 @@ static const struct dev_pm_ops rcar_lvds_pm_ops = {
 
 static struct platform_driver rcar_lvds_platform_driver = {
 	.probe		= rcar_lvds_probe,
-	.remove		= rcar_lvds_remove,
+	.remove_new	= rcar_lvds_remove,
 	.driver		= {
 		.name	= "rcar-lvds",
 		.pm	= &rcar_lvds_pm_ops,

drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c

@@ -1044,13 +1044,11 @@ static int rcar_mipi_dsi_probe(struct platform_device *pdev)
 	return 0;
 }
 
-static int rcar_mipi_dsi_remove(struct platform_device *pdev)
+static void rcar_mipi_dsi_remove(struct platform_device *pdev)
 {
 	struct rcar_mipi_dsi *dsi = platform_get_drvdata(pdev);
 
 	mipi_dsi_host_unregister(&dsi->host);
-
-	return 0;
 }
 
 static const struct rcar_mipi_dsi_device_info v3u_data = {
@@ -1093,7 +1091,7 @@ MODULE_DEVICE_TABLE(of, rcar_mipi_dsi_of_table);
 
 static struct platform_driver rcar_mipi_dsi_platform_driver = {
 	.probe          = rcar_mipi_dsi_probe,
-	.remove         = rcar_mipi_dsi_remove,
+	.remove_new     = rcar_mipi_dsi_remove,
 	.driver         = {
 		.name   = "rcar-mipi-dsi",
 		.of_match_table = rcar_mipi_dsi_of_table,

drivers/gpu/drm/rcar-du/rzg2l_mipi_dsi.c

@@ -782,14 +782,12 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
 	return ret;
 }
 
-static int rzg2l_mipi_dsi_remove(struct platform_device *pdev)
+static void rzg2l_mipi_dsi_remove(struct platform_device *pdev)
 {
 	struct rzg2l_mipi_dsi *dsi = platform_get_drvdata(pdev);
 
 	mipi_dsi_host_unregister(&dsi->host);
 	pm_runtime_disable(&pdev->dev);
-
-	return 0;
 }
 
 static const struct of_device_id rzg2l_mipi_dsi_of_table[] = {
@@ -801,7 +799,7 @@ MODULE_DEVICE_TABLE(of, rzg2l_mipi_dsi_of_table);
 
 static struct platform_driver rzg2l_mipi_dsi_platform_driver = {
 	.probe	= rzg2l_mipi_dsi_probe,
-	.remove	= rzg2l_mipi_dsi_remove,
+	.remove_new = rzg2l_mipi_dsi_remove,
 	.driver	= {
 		.name = "rzg2l-mipi-dsi",
 		.pm = &rzg2l_mipi_pm_ops,