[v6,3/7] drm/tilcdc: Add support for external tda998x encoder

diff --git a/Documentation/devicetree/bindings/drm/tilcdc/tilcdc.txt b/Documentation/devicetree/bindings/drm/tilcdc/tilcdc.txt
index fff10da..2136ee8 100644
--- a/Documentation/devicetree/bindings/drm/tilcdc/tilcdc.txt
+++ b/Documentation/devicetree/bindings/drm/tilcdc/tilcdc.txt
@@ -18,6 +18,12 @@  Optional properties:
  - max-pixelclock: The maximum pixel clock that can be supported
    by the lcd controller in KHz.
 
+Optional nodes:
+
+ - port/ports: to describe a connection to an external encoder. The
+   binding follows Documentation/devicetree/bindings/graph.txt and
+   suppors a single port with a single endpoint.
+
 Example:
 
 	fb: fb@4830e000 {
@@ -26,4 +32,25 @@  Example:
 		interrupt-parent = <&intc>;
 		interrupts = <36>;
 		ti,hwmods = "lcdc";
+
+		port {
+			lcdc_0: endpoint@0 {
+				remote-endpoint = <&hdmi_0>;
+			};
+		};
+	};
+
+	tda19988: tda19988 {
+		compatible = "nxp,tda998x";
+		reg = <0x70>;
+
+		pinctrl-names = "default", "off";
+		pinctrl-0 = <&nxp_hdmi_bonelt_pins>;
+		pinctrl-1 = <&nxp_hdmi_bonelt_off_pins>;
+
+		port {
+			hdmi_0: endpoint@0 {
+				remote-endpoint = <&lcdc_0>;
+			};
+		};
 	};
diff --git a/drivers/gpu/drm/tilcdc/Makefile b/drivers/gpu/drm/tilcdc/Makefile
index 44485f9..e1f738b 100644
--- a/drivers/gpu/drm/tilcdc/Makefile
+++ b/drivers/gpu/drm/tilcdc/Makefile
@@ -7,6 +7,7 @@  tilcdc-y := \
 	tilcdc_crtc.o \
 	tilcdc_tfp410.o \
 	tilcdc_panel.o \
+	tilcdc_external.o \
 	tilcdc_drv.o
 
 obj-$(CONFIG_DRM_TILCDC)	+= tilcdc.o
diff --git a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
index c2d5980..7d07733 100644
--- a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
+++ b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
@@ -37,6 +37,9 @@  struct tilcdc_crtc {
 
 	/* for deferred fb unref's: */
 	struct drm_flip_work unref_work;
+
+	/* Only set if an external encoder is connected */
+	bool simulate_vesa_sync;
 };
 #define to_tilcdc_crtc(x) container_of(x, struct tilcdc_crtc, base)
 
@@ -214,6 +217,28 @@  static bool tilcdc_crtc_mode_fixup(struct drm_crtc *crtc,
 		const struct drm_display_mode *mode,
 		struct drm_display_mode *adjusted_mode)
 {
+	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
+
+	if (!tilcdc_crtc->simulate_vesa_sync)
+		return true;
+
+	/*
+	 * tilcdc does not generate VESA-compliant sync but aligns
+	 * VS on the second edge of HS instead of first edge.
+	 * We use adjusted_mode, to fixup sync by aligning both rising
+	 * edges and add HSKEW offset to fix the sync.
+	 */
+	adjusted_mode->hskew = mode->hsync_end - mode->hsync_start;
+	adjusted_mode->flags |= DRM_MODE_FLAG_HSKEW;
+
+	if (mode->flags & DRM_MODE_FLAG_NHSYNC) {
+		adjusted_mode->flags |= DRM_MODE_FLAG_PHSYNC;
+		adjusted_mode->flags &= ~DRM_MODE_FLAG_NHSYNC;
+	} else {
+		adjusted_mode->flags |= DRM_MODE_FLAG_NHSYNC;
+		adjusted_mode->flags &= ~DRM_MODE_FLAG_PHSYNC;
+	}
+
 	return true;
 }
 
@@ -534,6 +559,14 @@  void tilcdc_crtc_set_panel_info(struct drm_crtc *crtc,
 	tilcdc_crtc->info = info;
 }
 
+void tilcdc_crtc_set_simulate_vesa_sync(struct drm_crtc *crtc,
+					bool simulate_vesa_sync)
+{
+	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
+
+	tilcdc_crtc->simulate_vesa_sync = simulate_vesa_sync;
+}
+
 void tilcdc_crtc_update_clk(struct drm_crtc *crtc)
 {
 	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
diff --git a/drivers/gpu/drm/tilcdc/tilcdc_drv.c b/drivers/gpu/drm/tilcdc/tilcdc_drv.c
index 0f1e099..fcc0508 100644
--- a/drivers/gpu/drm/tilcdc/tilcdc_drv.c
+++ b/drivers/gpu/drm/tilcdc/tilcdc_drv.c
@@ -17,10 +17,13 @@ 
 
 /* LCDC DRM driver, based on da8xx-fb */
 
+#include <linux/component.h>
+
 #include "tilcdc_drv.h"
 #include "tilcdc_regs.h"
 #include "tilcdc_tfp410.h"
 #include "tilcdc_panel.h"
+#include "tilcdc_external.h"
 
 #include "drm_fb_helper.h"
 
@@ -73,13 +76,6 @@  static int modeset_init(struct drm_device *dev)
 		mod->funcs->modeset_init(mod, dev);
 	}
 
-	if ((priv->num_encoders == 0) || (priv->num_connectors == 0)) {
-		/* oh nos! */
-		dev_err(dev->dev, "no encoders/connectors found\n");
-		drm_mode_config_cleanup(dev);
-		return -ENXIO;
-	}
-
 	dev->mode_config.min_width = 0;
 	dev->mode_config.min_height = 0;
 	dev->mode_config.max_width = tilcdc_crtc_max_width(priv->crtc);
@@ -114,6 +110,8 @@  static int tilcdc_unload(struct drm_device *dev)
 {
 	struct tilcdc_drm_private *priv = dev->dev_private;
 
+	tilcdc_remove_external_encoders(dev);
+
 	drm_fbdev_cma_fini(priv->fbdev);
 	drm_kms_helper_poll_fini(dev);
 	drm_mode_config_cleanup(dev);
@@ -164,6 +162,9 @@  static int tilcdc_load(struct drm_device *dev, unsigned long flags)
 
 	dev->dev_private = priv;
 
+	priv->is_componentized =
+		tilcdc_get_external_components(dev->dev, NULL) > 0;
+
 	priv->wq = alloc_ordered_workqueue("tilcdc", 0);
 	if (!priv->wq) {
 		ret = -ENOMEM;
@@ -253,10 +254,28 @@  static int tilcdc_load(struct drm_device *dev, unsigned long flags)
 		goto fail_cpufreq_unregister;
 	}
 
+	platform_set_drvdata(pdev, dev);
+
+	if (priv->is_componentized) {
+		ret = component_bind_all(dev->dev, dev);
+		if (ret < 0)
+			goto fail_mode_config_cleanup;
+
+		ret = tilcdc_add_external_encoders(dev, &bpp);
+		if (ret < 0)
+			goto fail_component_cleanup;
+	}
+
+	if ((priv->num_encoders == 0) || (priv->num_connectors == 0)) {
+		dev_err(dev->dev, "no encoders/connectors found\n");
+		ret = -ENXIO;
+		goto fail_external_cleanup;
+	}
+
 	ret = drm_vblank_init(dev, 1);
 	if (ret < 0) {
 		dev_err(dev->dev, "failed to initialize vblank\n");
-		goto fail_mode_config_cleanup;
+		goto fail_external_cleanup;
 	}
 
 	pm_runtime_get_sync(dev->dev);
@@ -267,9 +286,6 @@  static int tilcdc_load(struct drm_device *dev, unsigned long flags)
 		goto fail_vblank_cleanup;
 	}
 
-	platform_set_drvdata(pdev, dev);
-
-
 	list_for_each_entry(mod, &module_list, list) {
 		DBG("%s: preferred_bpp: %d", mod->name, mod->preferred_bpp);
 		bpp = mod->preferred_bpp;
@@ -300,6 +316,13 @@  fail_vblank_cleanup:
 fail_mode_config_cleanup:
 	drm_mode_config_cleanup(dev);
 
+fail_component_cleanup:
+	if (priv->is_componentized)
+		component_unbind_all(dev->dev, dev);
+
+fail_external_cleanup:
+	tilcdc_remove_external_encoders(dev);
+
 fail_cpufreq_unregister:
 	pm_runtime_disable(dev->dev);
 #ifdef CONFIG_CPU_FREQ
@@ -605,20 +628,56 @@  static const struct dev_pm_ops tilcdc_pm_ops = {
  * Platform driver:
  */
 
+static int tilcdc_bind(struct device *dev)
+{
+	return drm_platform_init(&tilcdc_driver, to_platform_device(dev));
+}
+
+static void tilcdc_unbind(struct device *dev)
+{
+	drm_put_dev(dev_get_drvdata(dev));
+}
+
+static const struct component_master_ops tilcdc_comp_ops = {
+	.bind = tilcdc_bind,
+	.unbind = tilcdc_unbind,
+};
+
 static int tilcdc_pdev_probe(struct platform_device *pdev)
 {
+	struct component_match *match = NULL;
+	int ret;
+
 	/* bail out early if no DT data: */
 	if (!pdev->dev.of_node) {
 		dev_err(&pdev->dev, "device-tree data is missing\n");
 		return -ENXIO;
 	}
 
-	return drm_platform_init(&tilcdc_driver, pdev);
+	ret = tilcdc_get_external_components(&pdev->dev, &match);
+	if (ret < 0)
+		return ret;
+	else if (ret == 0)
+		return drm_platform_init(&tilcdc_driver, pdev);
+	else
+		return component_master_add_with_match(&pdev->dev,
+						       &tilcdc_comp_ops,
+						       match);
 }
 
 static int tilcdc_pdev_remove(struct platform_device *pdev)
 {
-	drm_put_dev(platform_get_drvdata(pdev));
+	struct drm_device *ddev = dev_get_drvdata(&pdev->dev);
+	struct tilcdc_drm_private *priv = ddev->dev_private;
+
+	/* Check if a subcomponent has already triggered the unloading. */
+	if (!priv)
+		return 0;
+
+	if (priv->is_componentized)
+		component_master_del(&pdev->dev, &tilcdc_comp_ops);
+	else
+		drm_put_dev(platform_get_drvdata(pdev));
 
 	return 0;
 }
diff --git a/drivers/gpu/drm/tilcdc/tilcdc_drv.h b/drivers/gpu/drm/tilcdc/tilcdc_drv.h
index 6336512..e863ad0 100644
--- a/drivers/gpu/drm/tilcdc/tilcdc_drv.h
+++ b/drivers/gpu/drm/tilcdc/tilcdc_drv.h
@@ -85,6 +85,9 @@  struct tilcdc_drm_private {
 
 	unsigned int num_connectors;
 	struct drm_connector *connectors[8];
+	const struct drm_connector_helper_funcs *connector_funcs[8];
+
+	bool is_componentized;
 };
 
 /* Sub-module for display.  Since we don't know at compile time what panels
@@ -165,6 +168,8 @@  irqreturn_t tilcdc_crtc_irq(struct drm_crtc *crtc);
 void tilcdc_crtc_update_clk(struct drm_crtc *crtc);
 void tilcdc_crtc_set_panel_info(struct drm_crtc *crtc,
 		const struct tilcdc_panel_info *info);
+void tilcdc_crtc_set_simulate_vesa_sync(struct drm_crtc *crtc,
+					bool simulate_vesa_sync);
 int tilcdc_crtc_mode_valid(struct drm_crtc *crtc, struct drm_display_mode *mode);
 int tilcdc_crtc_max_width(struct drm_crtc *crtc);
 
diff --git a/drivers/gpu/drm/tilcdc/tilcdc_external.c b/drivers/gpu/drm/tilcdc/tilcdc_external.c
new file mode 100644
index 0000000..03acb4f
--- /dev/null
+++ b/drivers/gpu/drm/tilcdc/tilcdc_external.c
@@ -0,0 +1,166 @@ 
+/*
+ * Copyright (C) 2015 Texas Instruments
+ * Author: Jyri Sarha <jsarha@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ */
+
+#include <linux/component.h>
+#include <linux/of_graph.h>
+
+#include "tilcdc_drv.h"
+#include "tilcdc_external.h"
+
+static const struct tilcdc_panel_info panel_info_tda998x = {
+		.ac_bias                = 255,
+		.ac_bias_intrpt         = 0,
+		.dma_burst_sz           = 16,
+		.bpp                    = 16,
+		.fdd                    = 0x80,
+		.tft_alt_mode           = 0,
+		.invert_pxl_clk		= 1,
+		.sync_edge              = 1,
+		.sync_ctrl              = 1,
+		.raster_order           = 0,
+};
+
+static int tilcdc_external_mode_valid(struct drm_connector *connector,
+				      struct drm_display_mode *mode)
+{
+	struct tilcdc_drm_private *priv = connector->dev->dev_private;
+	int ret, i;
+
+	ret = tilcdc_crtc_mode_valid(priv->crtc, mode);
+	if (ret != MODE_OK)
+		return ret;
+
+	for (i = 0; i < priv->num_connectors &&
+		     priv->connectors[i] != connector; i++)
+		;
+
+	BUG_ON(priv->connectors[i] != connector);
+	BUG_ON(!priv->connector_funcs[i]);
+
+	/* If the connector has its own mode_valid call it. */
+	if (!IS_ERR(priv->connector_funcs[i]) &&
+	    priv->connector_funcs[i]->mode_valid)
+		return priv->connector_funcs[i]->mode_valid(connector, mode);
+
+	return MODE_OK;
+}
+
+static int tilcdc_add_external_encoder(struct drm_device *dev, int *bpp,
+				       struct drm_connector *connector)
+{
+	struct tilcdc_drm_private *priv = dev->dev_private;
+	struct drm_connector_helper_funcs *connector_funcs;
+
+	priv->connectors[priv->num_connectors] = connector;
+	priv->encoders[priv->num_encoders++] = connector->encoder;
+
+	/* Only tda998x is supported at the moment. */
+	tilcdc_crtc_set_simulate_vesa_sync(priv->crtc, true);
+	tilcdc_crtc_set_panel_info(priv->crtc, &panel_info_tda998x);
+	*bpp = panel_info_tda998x.bpp;
+
+	connector_funcs = devm_kzalloc(dev->dev, sizeof(*connector_funcs),
+				       GFP_KERNEL);
+	if (!connector_funcs)
+		return -ENOMEM;
+
+	/* connector->helper_private contains always struct
+	 * connector_helper_funcs pointer. For tilcdc crtc to have a
+	 * say if a specific mode is Ok, we need to install our own
+	 * helper functions. In our helper functions we copy
+	 * everything else but use our own mode_valid() (above).
+	 */
+	if (connector->helper_private) {
+		priv->connector_funcs[priv->num_connectors] =
+			connector->helper_private;
+		*connector_funcs = *priv->connector_funcs[priv->num_connectors];
+	} else {
+		priv->connector_funcs[priv->num_connectors] = ERR_PTR(-ENOENT);
+	}
+	connector_funcs->mode_valid = tilcdc_external_mode_valid;
+	drm_connector_helper_add(connector, connector_funcs);
+	priv->num_connectors++;
+
+	dev_dbg(dev->dev, "External encoder '%s' connected\n",
+		connector->encoder->name);
+
+	return 0;
+}
+
+int tilcdc_add_external_encoders(struct drm_device *dev, int *bpp)
+{
+	struct tilcdc_drm_private *priv = dev->dev_private;
+	struct drm_connector *connector;
+	int num_internal_connectors = priv->num_connectors;
+
+	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
+		bool found = false;
+		int i, ret;
+
+		for (i = 0; i < num_internal_connectors; i++)
+			if (connector == priv->connectors[i])
+				found = true;
+		if (!found) {
+			ret = tilcdc_add_external_encoder(dev, bpp, connector);
+			if (ret)
+				return ret;
+		}
+	}
+	return 0;
+}
+
+void tilcdc_remove_external_encoders(struct drm_device *dev)
+{
+	struct tilcdc_drm_private *priv = dev->dev_private;
+	int i;
+
+	/* Restore the original helper functions, if any. */
+	for (i = 0; i < priv->num_connectors; i++)
+		if (IS_ERR(priv->connector_funcs[i]))
+			drm_connector_helper_add(priv->connectors[i], NULL);
+		else if (priv->connector_funcs[i])
+			drm_connector_helper_add(priv->connectors[i],
+						 priv->connector_funcs[i]);
+}
+
+static int dev_match_of(struct device *dev, void *data)
+{
+	return dev->of_node == data;
+}
+
+int tilcdc_get_external_components(struct device *dev,
+				   struct component_match **match)
+{
+	struct device_node *ep = NULL;
+	int count = 0;
+
+	while ((ep = of_graph_get_next_endpoint(dev->of_node, ep))) {
+		struct device_node *node;
+
+		node = of_graph_get_remote_port_parent(ep);
+		if (!node && !of_device_is_available(node)) {
+			of_node_put(node);
+			continue;
+		}
+
+		dev_dbg(dev, "Subdevice node '%s' found\n", node->name);
+		if (match)
+			component_match_add(dev, match, dev_match_of, node);
+		of_node_put(node);
+		count++;
+	}
+
+	if (count > 1) {
+		dev_err(dev, "Only one external encoder is supported\n");
+		return -EINVAL;
+	}
+
+	return count;
+}
diff --git a/drivers/gpu/drm/tilcdc/tilcdc_external.h b/drivers/gpu/drm/tilcdc/tilcdc_external.h
new file mode 100644
index 0000000..6aabe27
--- /dev/null
+++ b/drivers/gpu/drm/tilcdc/tilcdc_external.h
@@ -0,0 +1,25 @@ 
+/*
+ * Copyright (C) 2015 Texas Instruments
+ * Author: Jyri Sarha <jsarha@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __TILCDC_EXTERNAL_H__
+#define __TILCDC_EXTERNAL_H__
+
+int tilcdc_add_external_encoders(struct drm_device *dev, int *bpp);
+void tilcdc_remove_external_encoders(struct drm_device *dev);
+int tilcdc_get_external_components(struct device *dev,
+				   struct component_match **match);
+#endif /* __TILCDC_SLAVE_H__ */