drm/tegra: hub: Enable all required clocks

index 6112d9042979..922a48d5a483 100644
@@ -742,7 +742,9 @@ static const struct host1x_client_ops tegra_display_hub_ops = {
 
 static int tegra_display_hub_probe(struct platform_device *pdev)
 {
+	struct device_node *child = NULL;
 	struct tegra_display_hub *hub;
+	struct clk *clk;
 	unsigned int i;
 	int err;
 

@@ -801,6 +803,34 @@ static int tegra_display_hub_probe(struct platform_device *pdev)
 			return err;
 	}
 
+	hub->num_heads = of_get_child_count(pdev->dev.of_node);
+
+	hub->clk_heads = devm_kcalloc(&pdev->dev, hub->num_heads, sizeof(clk),
+				      GFP_KERNEL);
+	if (!hub->clk_heads)
+		return -ENOMEM;
+
+	for (i = 0; i < hub->num_heads; i++) {
+		child = of_get_next_child(pdev->dev.of_node, child);
+		if (!child) {
+			dev_err(&pdev->dev, "failed to find node for head %u\n",
+				i);
+			return -ENODEV;
+		}
+
+		clk = devm_get_clk_from_child(&pdev->dev, child, "dc");
+		if (IS_ERR(clk)) {
+			dev_err(&pdev->dev, "failed to get clock for head %u\n",
+				i);
+			of_node_put(child);
+			return PTR_ERR(clk);
+		}
+
+		hub->clk_heads[i] = clk;
+	}
+
+	of_node_put(child);
+
 	/* XXX: enable clock across reset? */
 	err = reset_control_assert(hub->rst);
 	if (err < 0)

@@ -840,12 +870,16 @@ static int tegra_display_hub_remove(struct platform_device *pdev)
 static int __maybe_unused tegra_display_hub_suspend(struct device *dev)
 {
 	struct tegra_display_hub *hub = dev_get_drvdata(dev);
+	unsigned int i = hub->num_heads;
 	int err;
 
 	err = reset_control_assert(hub->rst);
 	if (err < 0)
 		return err;
 
+	while (i--)
+		clk_disable_unprepare(hub->clk_heads[i]);
+
 	clk_disable_unprepare(hub->clk_hub);
 	clk_disable_unprepare(hub->clk_dsc);
 	clk_disable_unprepare(hub->clk_disp);

@@ -856,6 +890,7 @@ static int __maybe_unused tegra_display_hub_suspend(struct device *dev)
 static int __maybe_unused tegra_display_hub_resume(struct device *dev)
 {
 	struct tegra_display_hub *hub = dev_get_drvdata(dev);
+	unsigned int i;
 	int err;
 
 	err = clk_prepare_enable(hub->clk_disp);

@@ -870,13 +905,22 @@ static int __maybe_unused tegra_display_hub_resume(struct device *dev)
 	if (err < 0)
 		goto disable_dsc;
 
+	for (i = 0; i < hub->num_heads; i++) {
+		err = clk_prepare_enable(hub->clk_heads[i]);
+		if (err < 0)
+			goto disable_heads;
+	}
+
 	err = reset_control_deassert(hub->rst);
 	if (err < 0)
-		goto disable_hub;
+		goto disable_heads;
 
 	return 0;
 
-disable_hub:
+disable_heads:
+	while (i--)
+		clk_disable_unprepare(hub->clk_heads[i]);
+
 	clk_disable_unprepare(hub->clk_hub);
 disable_dsc:
 	clk_disable_unprepare(hub->clk_dsc);

index 6696a85fc1f2..479087c0705a 100644
@@ -49,6 +49,9 @@ struct tegra_display_hub {
 	struct clk *clk_hub;
 	struct reset_control *rst;
 
+	unsigned int num_heads;
+	struct clk **clk_heads;
+
 	const struct tegra_display_hub_soc *soc;
 	struct tegra_windowgroup *wgrps;
 };

index f80e82e16475..607a6ea17ecc 100644
@@ -1978,6 +1978,23 @@ static irqreturn_t tegra_dc_irq(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
+static bool tegra_dc_has_window_groups(struct tegra_dc *dc)
+{
+	unsigned int i;
+
+	if (!dc->soc->wgrps)
+		return true;
+
+	for (i = 0; i < dc->soc->num_wgrps; i++) {
+		const struct tegra_windowgroup_soc *wgrp = &dc->soc->wgrps[i];
+
+		if (wgrp->dc == dc->pipe && wgrp->num_windows > 0)
+			return true;
+	}
+
+	return false;
+}
+
 static int tegra_dc_init(struct host1x_client *client)
 {
 	struct drm_device *drm = dev_get_drvdata(client->parent);

@@ -1993,22 +2010,8 @@ static int tegra_dc_init(struct host1x_client *client)
 	 * assign a primary plane to them, which in turn will cause KMS to
 	 * crash.
 	 */
-	if (dc->soc->wgrps) {
-		bool has_wgrps = false;
-		unsigned int i;
-
-		for (i = 0; i < dc->soc->num_wgrps; i++) {
-			const struct tegra_windowgroup_soc *wgrp = &dc->soc->wgrps[i];
-
-			if (wgrp->dc == dc->pipe && wgrp->num_windows > 0) {
-				has_wgrps = true;
-				break;
-			}
-		}
-
-		if (!has_wgrps)
-			return 0;
-	}
+	if (!tegra_dc_has_window_groups(dc))
+		return 0;
 
 	dc->syncpt = host1x_syncpt_request(client, flags);
 	if (!dc->syncpt)

@@ -2094,6 +2097,9 @@ static int tegra_dc_exit(struct host1x_client *client)
 	struct tegra_dc *dc = host1x_client_to_dc(client);
 	int err;
 
+	if (!tegra_dc_has_window_groups(dc))
+		return 0;
+
 	devm_free_irq(dc->dev, dc->irq, dc);
 
 	err = tegra_dc_rgb_exit(dc);

index 6112d9042979..d597de7d0de4 100644
@@ -742,6 +742,7 @@ static const struct host1x_client_ops tegra_display_hub_ops = {
 
 static int tegra_display_hub_probe(struct platform_device *pdev)
 {
+	struct device_node *child = NULL;
 	struct tegra_display_hub *hub;
 	unsigned int i;
 	int err;

@@ -801,6 +802,29 @@ static int tegra_display_hub_probe(struct platform_device *pdev)
 			return err;
 	}
 
+	hub->num_heads = of_get_child_count(pdev->dev.of_node);
+
+	hub->clk_heads = devm_kcalloc(&pdev->dev, hub->num_heads,
+				      sizeof(*hub->clk_heads), GFP_KERNEL);
+	if (!hub->clk_heads)
+		return -ENOMEM;
+
+	for (i = 0; i < hub->num_heads; i++) {
+		child = of_get_next_child(pdev->dev.of_node, child);
+
+		hub->clk_heads[i].id = "dc";
+		hub->clk_heads[i].clk = devm_get_clk_from_child(&pdev->dev,
+								child, "dc");
+		if (IS_ERR(hub->clk_heads[i].clk)) {
+			dev_err(&pdev->dev, "failed to get clock for head %u\n",
+				i);
+			of_node_put(child);
+			return PTR_ERR(hub->clk_heads[i].clk);
+		}
+	}
+
+	of_node_put(child);
+
 	/* XXX: enable clock across reset? */
 	err = reset_control_assert(hub->rst);
 	if (err < 0)

@@ -846,6 +870,7 @@ static int __maybe_unused tegra_display_hub_suspend(struct device *dev)
 	if (err < 0)
 		return err;
 
+	clk_bulk_disable_unprepare(hub->num_heads, hub->clk_heads);
 	clk_disable_unprepare(hub->clk_hub);
 	clk_disable_unprepare(hub->clk_dsc);
 	clk_disable_unprepare(hub->clk_disp);

@@ -870,12 +895,18 @@ static int __maybe_unused tegra_display_hub_resume(struct device *dev)
 	if (err < 0)
 		goto disable_dsc;
 
-	err = reset_control_deassert(hub->rst);
+	err = clk_bulk_prepare_enable(hub->num_heads, hub->clk_heads);
 	if (err < 0)
 		goto disable_hub;
 
+	err = reset_control_deassert(hub->rst);
+	if (err < 0)
+		goto disable_heads;
+
 	return 0;
 
+disable_heads:
+	clk_bulk_disable_unprepare(hub->num_heads, hub->clk_heads);
 disable_hub:
 	clk_disable_unprepare(hub->clk_hub);
 disable_dsc:

index 6696a85fc1f2..40866765ef0d 100644
@@ -49,6 +49,9 @@ struct tegra_display_hub {
 	struct clk *clk_hub;
 	struct reset_control *rst;
 
+	unsigned int num_heads;
+	struct clk_bulk_data *clk_heads;
+
 	const struct tegra_display_hub_soc *soc;
 	struct tegra_windowgroup *wgrps;
 };