drm/ingenic: Call drm_atomic_helper_shutdown() at shutdown time

Based on grepping through the source code this driver appears to be
missing a call to drm_atomic_helper_shutdown() at system shutdown
time. Among other things, this means that if a panel is in use that it
won't be cleanly powered off at system shutdown time.

The fact that we should call drm_atomic_helper_shutdown() in the case
of OS shutdown/restart comes straight out of the kernel doc "driver
instance overview" in drm_drv.c.

Since this driver uses the component model and shutdown happens at the
base driver, we communicate whether we have to call
drm_atomic_helper_shutdown() by seeing if drvdata is non-NULL.
Suggested-by: Maxime Ripard <mripard@kernel.org>
Acked-by: Paul Cercueil <paul@crapouillou.net>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230901164111.RFT.3.Iea742f06d8bec41598aa40378fc625fbd7e8a3d6@changeid

drivers/gpu/drm/ingenic/ingenic-drm-drv.c

@@ -1130,7 +1130,7 @@ static int ingenic_drm_bind(struct device *dev, bool has_components)
 
 	ret = drmm_mode_config_init(drm);
 	if (ret)
-		return ret;
+		goto err_drvdata;
 
 	drm->mode_config.min_width = 0;
 	drm->mode_config.min_height = 0;
@@ -1142,7 +1142,8 @@ static int ingenic_drm_bind(struct device *dev, bool has_components)
 	base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
 	if (IS_ERR(base)) {
 		dev_err(dev, "Failed to get memory resource\n");
-		return PTR_ERR(base);
+		ret = PTR_ERR(base);
+		goto err_drvdata;
 	}
 
 	regmap_config = ingenic_drm_regmap_config;
@@ -1151,33 +1152,40 @@ static int ingenic_drm_bind(struct device *dev, bool has_components)
 					  &regmap_config);
 	if (IS_ERR(priv->map)) {
 		dev_err(dev, "Failed to create regmap\n");
-		return PTR_ERR(priv->map);
+		ret = PTR_ERR(priv->map);
+		goto err_drvdata;
 	}
 
 	irq = platform_get_irq(pdev, 0);
-	if (irq < 0)
-		return irq;
+	if (irq < 0) {
+		ret = irq;
+		goto err_drvdata;
+	}
 
 	if (soc_info->needs_dev_clk) {
 		priv->lcd_clk = devm_clk_get(dev, "lcd");
 		if (IS_ERR(priv->lcd_clk)) {
 			dev_err(dev, "Failed to get lcd clock\n");
-			return PTR_ERR(priv->lcd_clk);
+			ret = PTR_ERR(priv->lcd_clk);
+			goto err_drvdata;
 		}
 	}
 
 	priv->pix_clk = devm_clk_get(dev, "lcd_pclk");
 	if (IS_ERR(priv->pix_clk)) {
 		dev_err(dev, "Failed to get pixel clock\n");
-		return PTR_ERR(priv->pix_clk);
+		ret = PTR_ERR(priv->pix_clk);
+		goto err_drvdata;
 	}
 
 	priv->dma_hwdescs = dmam_alloc_coherent(dev,
 						sizeof(*priv->dma_hwdescs),
 						&priv->dma_hwdescs_phys,
 						GFP_KERNEL);
-	if (!priv->dma_hwdescs)
-		return -ENOMEM;
+	if (!priv->dma_hwdescs) {
+		ret = -ENOMEM;
+		goto err_drvdata;
+	}
 
 	/* Configure DMA hwdesc for foreground0 plane */
 	ingenic_drm_configure_hwdesc_plane(priv, 0);
@@ -1199,7 +1207,7 @@ static int ingenic_drm_bind(struct device *dev, bool has_components)
 				       NULL, DRM_PLANE_TYPE_PRIMARY, NULL);
 	if (ret) {
 		dev_err(dev, "Failed to register plane: %i\n", ret);
-		return ret;
+		goto err_drvdata;
 	}
 
 	if (soc_info->map_noncoherent)
@@ -1211,7 +1219,7 @@ static int ingenic_drm_bind(struct device *dev, bool has_components)
 					NULL, &ingenic_drm_crtc_funcs, NULL);
 	if (ret) {
 		dev_err(dev, "Failed to init CRTC: %i\n", ret);
-		return ret;
+		goto err_drvdata;
 	}
 
 	drm_crtc_enable_color_mgmt(&priv->crtc, 0, false,
@@ -1230,7 +1238,7 @@ static int ingenic_drm_bind(struct device *dev, bool has_components)
 		if (ret) {
 			dev_err(dev, "Failed to register overlay plane: %i\n",
 				ret);
-			return ret;
+			goto err_drvdata;
 		}
 
 		if (soc_info->map_noncoherent)
@@ -1241,17 +1249,18 @@ static int ingenic_drm_bind(struct device *dev, bool has_components)
 			if (ret) {
 				if (ret != -EPROBE_DEFER)
 					dev_err(dev, "Failed to bind components: %i\n", ret);
-				return ret;
+				goto err_drvdata;
 			}
 
 			ret = devm_add_action_or_reset(dev, ingenic_drm_unbind_all, priv);
 			if (ret)
-				return ret;
+				goto err_drvdata;
 
 			priv->ipu_plane = drm_plane_from_index(drm, 2);
 			if (!priv->ipu_plane) {
 				dev_err(dev, "Failed to retrieve IPU plane\n");
-				return -EINVAL;
+				ret = -EINVAL;
+				goto err_drvdata;
 			}
 		}
 	}
@@ -1263,7 +1272,7 @@ static int ingenic_drm_bind(struct device *dev, bool has_components)
 				break; /* we're done */
 			if (ret != -EPROBE_DEFER)
 				dev_err(dev, "Failed to get bridge handle\n");
-			return ret;
+			goto err_drvdata;
 		}
 
 		if (panel)
@@ -1275,7 +1284,7 @@ static int ingenic_drm_bind(struct device *dev, bool has_components)
 		if (IS_ERR(ib)) {
 			ret = PTR_ERR(ib);
 			dev_err(dev, "Failed to init encoder: %d\n", ret);
-			return ret;
+			goto err_drvdata;
 		}
 
 		encoder = &ib->encoder;
@@ -1290,13 +1299,14 @@ static int ingenic_drm_bind(struct device *dev, bool has_components)
 					DRM_BRIDGE_ATTACH_NO_CONNECTOR);
 		if (ret) {
 			dev_err(dev, "Unable to attach bridge\n");
-			return ret;
+			goto err_drvdata;
 		}
 
 		connector = drm_bridge_connector_init(drm, encoder);
 		if (IS_ERR(connector)) {
 			dev_err(dev, "Unable to init connector\n");
-			return PTR_ERR(connector);
+			ret = PTR_ERR(connector);
+			goto err_drvdata;
 		}
 
 		drm_connector_attach_encoder(connector, encoder);
@@ -1313,13 +1323,13 @@ static int ingenic_drm_bind(struct device *dev, bool has_components)
 	ret = devm_request_irq(dev, irq, ingenic_drm_irq_handler, 0, drm->driver->name, drm);
 	if (ret) {
 		dev_err(dev, "Unable to install IRQ handler\n");
-		return ret;
+		goto err_drvdata;
 	}
 
 	ret = drm_vblank_init(drm, 1);
 	if (ret) {
 		dev_err(dev, "Failed calling drm_vblank_init()\n");
-		return ret;
+		goto err_drvdata;
 	}
 
 	drm_mode_config_reset(drm);
@@ -1327,7 +1337,7 @@ static int ingenic_drm_bind(struct device *dev, bool has_components)
 	ret = clk_prepare_enable(priv->pix_clk);
 	if (ret) {
 		dev_err(dev, "Unable to start pixel clock\n");
-		return ret;
+		goto err_drvdata;
 	}
 
 	if (priv->lcd_clk) {
@@ -1402,6 +1412,8 @@ static int ingenic_drm_bind(struct device *dev, bool has_components)
 		clk_disable_unprepare(priv->lcd_clk);
 err_pixclk_disable:
 	clk_disable_unprepare(priv->pix_clk);
+err_drvdata:
+	platform_set_drvdata(pdev, NULL);
 	return ret;
 }
 
@@ -1422,6 +1434,7 @@ static void ingenic_drm_unbind(struct device *dev)
 
 	drm_dev_unregister(&priv->drm);
 	drm_atomic_helper_shutdown(&priv->drm);
+	dev_set_drvdata(dev, NULL);
 }
 
 static const struct component_master_ops ingenic_master_ops = {
@@ -1459,6 +1472,14 @@ static void ingenic_drm_remove(struct platform_device *pdev)
 		component_master_del(dev, &ingenic_master_ops);
 }
 
+static void ingenic_drm_shutdown(struct platform_device *pdev)
+{
+	struct ingenic_drm *priv = platform_get_drvdata(pdev);
+
+	if (priv)
+		drm_atomic_helper_shutdown(&priv->drm);
+}
+
 static int ingenic_drm_suspend(struct device *dev)
 {
 	struct ingenic_drm *priv = dev_get_drvdata(dev);
@@ -1610,6 +1631,7 @@ static struct platform_driver ingenic_drm_driver = {
 	},
 	.probe = ingenic_drm_probe,
 	.remove_new = ingenic_drm_remove,
+	.shutdown = ingenic_drm_shutdown,
 };
 
 static int ingenic_drm_init(void)