drm/tegra: hub: Add Tegra194 support

The display hub integrated into Tegra194 is almost identical to the one
found on Tegra186. However, it doesn't support DSC (display stream
compression) so it isn't fully compatible.
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/gpu/drm/tegra/drm.c

@@ -1255,6 +1255,7 @@ static const struct of_device_id host1x_drm_subdevs[] = {
 	{ .compatible = "nvidia,tegra186-sor", },
 	{ .compatible = "nvidia,tegra186-sor1", },
 	{ .compatible = "nvidia,tegra186-vic", },
+	{ .compatible = "nvidia,tegra194-display", },
 	{ /* sentinel */ }
 };
 

drivers/gpu/drm/tegra/hub.c

@@ -758,10 +758,12 @@ static int tegra_display_hub_probe(struct platform_device *pdev)
 		return err;
 	}
 
-	hub->clk_dsc = devm_clk_get(&pdev->dev, "dsc");
-	if (IS_ERR(hub->clk_dsc)) {
-		err = PTR_ERR(hub->clk_dsc);
-		return err;
+	if (hub->soc->supports_dsc) {
+		hub->clk_dsc = devm_clk_get(&pdev->dev, "dsc");
+		if (IS_ERR(hub->clk_dsc)) {
+			err = PTR_ERR(hub->clk_dsc);
+			return err;
+		}
 	}
 
 	hub->clk_hub = devm_clk_get(&pdev->dev, "hub");
@@ -890,10 +892,19 @@ static const struct dev_pm_ops tegra_display_hub_pm_ops = {
 
 static const struct tegra_display_hub_soc tegra186_display_hub = {
 	.num_wgrps = 6,
+	.supports_dsc = true,
+};
+
+static const struct tegra_display_hub_soc tegra194_display_hub = {
+	.num_wgrps = 6,
+	.supports_dsc = false,
 };
 
 static const struct of_device_id tegra_display_hub_of_match[] = {
 	{
+		.compatible = "nvidia,tegra194-display",
+		.data = &tegra194_display_hub
+	}, {
 		.compatible = "nvidia,tegra186-display",
 		.data = &tegra186_display_hub
 	}, {

drivers/gpu/drm/tegra/hub.h

@@ -38,6 +38,7 @@ to_tegra_shared_plane(struct drm_plane *plane)
 
 struct tegra_display_hub_soc {
 	unsigned int num_wgrps;
+	bool supports_dsc;
 };
 
 struct tegra_display_hub {