[PATCH v2 2/3] drm/bridge: Add ti-tfp410 DVI transmitter driver

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




Add very basic ti-ftp410 DVI transmitter driver. The only feature
separating this from a completely dummy bridge is the EDID read
support trough DDC I2C. Even that functionality should be in a
separate generic connector driver. However, because of missing DRM
infrastructure support the connector is implemented within the bridge
driver. Some tfp410 HW specific features may be added later if needed,
because there is a set of registers behind i2c if it is connected.

This implementations is tested against my new tilcdc bridge support
and it works with BeagleBone DVI-D Cape Rev A3. A DT binding document
is also added.

Signed-off-by: Jyri Sarha <jsarha@xxxxxx>
---
 .../bindings/display/bridge/ti,tfp410.txt          |  41 ++++
 drivers/gpu/drm/bridge/Kconfig                     |   7 +
 drivers/gpu/drm/bridge/Makefile                    |   1 +
 drivers/gpu/drm/bridge/ti-tfp410.c                 | 223 +++++++++++++++++++++
 4 files changed, 272 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/bridge/ti,tfp410.txt
 create mode 100644 drivers/gpu/drm/bridge/ti-tfp410.c

diff --git a/Documentation/devicetree/bindings/display/bridge/ti,tfp410.txt b/Documentation/devicetree/bindings/display/bridge/ti,tfp410.txt
new file mode 100644
index 0000000..7446b2b
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/bridge/ti,tfp410.txt
@@ -0,0 +1,41 @@
+TFP410 DVI bridge bindings
+
+Required properties:
+	- compatible: "ti,tfp410"
+
+Optional properties
+	- reg: I2C address. If and only if present the driver node
+	  should be placed into the i2c controller node where the
+	  tfp410 i2c is connected to (the current implementation does
+	  not yet support this).
+
+Required subnodes:
+	- port@0: Video input port node to connect the bridge to a
+	  display controller output [1].
+	- port@1: Video output port node to connect the bridge to a
+	  connector input [1].
+
+[1]: Documentation/devicetree/bindings/media/video-interfaces.txt
+
+Example:
+	hdmi-bridge {
+		compatible = "ti,tfp410";
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			port@0 {
+				reg = <0>;
+				bridge_in: endpoint {
+					remote-endpoint = <&dc_out>;
+				};
+			};
+
+			port@1 {
+				reg = <1>;
+				bridge_out: endpoint {
+					remote-endpoint = <&hdmi_in>;
+				};
+			};
+		};
+	};
diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index bd6acc8..a424e03 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -81,6 +81,13 @@ config DRM_TOSHIBA_TC358767
 	---help---
 	  Toshiba TC358767 eDP bridge chip driver.
 
+config DRM_TI_TFP410
+	tristate "TI TFP410 DVI/HDMI bridge"
+	depends on OF
+	select DRM_KMS_HELPER
+	---help---
+	  Texas Instruments TFP410 DVI/HDMI Transmitter driver
+
 source "drivers/gpu/drm/bridge/analogix/Kconfig"
 
 source "drivers/gpu/drm/bridge/adv7511/Kconfig"
diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
index 97ed1a5..8b065d9 100644
--- a/drivers/gpu/drm/bridge/Makefile
+++ b/drivers/gpu/drm/bridge/Makefile
@@ -11,3 +11,4 @@ obj-$(CONFIG_DRM_SII902X) += sii902x.o
 obj-$(CONFIG_DRM_TOSHIBA_TC358767) += tc358767.o
 obj-$(CONFIG_DRM_ANALOGIX_DP) += analogix/
 obj-$(CONFIG_DRM_I2C_ADV7511) += adv7511/
+obj-$(CONFIG_DRM_TI_TFP410) += ti-tfp410.o
diff --git a/drivers/gpu/drm/bridge/ti-tfp410.c b/drivers/gpu/drm/bridge/ti-tfp410.c
new file mode 100644
index 0000000..a806cd6
--- /dev/null
+++ b/drivers/gpu/drm/bridge/ti-tfp410.c
@@ -0,0 +1,223 @@
+/*
+ * Copyright (C) 2016 Texas Instruments
+ * Author: Jyri Sarha <jsarha@xxxxxx>
+ *
+ * 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/module.h>
+#include <linux/of_graph.h>
+
+#include <drm/drmP.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc.h>
+#include <drm/drm_crtc_helper.h>
+
+struct tfp410 {
+	struct drm_bridge	bridge;
+	struct drm_connector	connector;
+
+	struct i2c_adapter	*ddc;
+
+	struct device *dev;
+};
+
+static inline struct tfp410 *
+drm_bridge_to_tfp410(struct drm_bridge *bridge)
+{
+	return container_of(bridge, struct tfp410, bridge);
+}
+
+static inline struct tfp410 *
+drm_connector_to_tfp410(struct drm_connector *connector)
+{
+	return container_of(connector, struct tfp410, connector);
+}
+
+static int tfp410_get_modes(struct drm_connector *connector)
+{
+	struct tfp410 *dvi = drm_connector_to_tfp410(connector);
+	struct edid *edid;
+	int ret;
+
+	if (!dvi->ddc)
+		goto fallback;
+
+	edid = drm_get_edid(connector, dvi->ddc);
+	if (!edid) {
+		DRM_INFO("EDID read failed. Fallback to standard modes\n");
+		goto fallback;
+	}
+
+	drm_mode_connector_update_edid_property(connector, edid);
+
+	return drm_add_edid_modes(connector, edid);
+fallback:
+	/* No EDID, fallback on the XGA standard modes */
+	ret = drm_add_modes_noedid(connector, 1920, 1200);
+
+	/* And prefer a mode pretty much anything can handle */
+	drm_set_preferred_mode(connector, 1024, 768);
+
+	return ret;
+}
+
+static const struct drm_connector_helper_funcs tfp410_con_helper_funcs = {
+	.get_modes	= tfp410_get_modes,
+};
+
+static enum drm_connector_status
+tfp410_connector_detect(struct drm_connector *connector, bool force)
+{
+	struct tfp410 *dvi = drm_connector_to_tfp410(connector);
+
+	if (dvi->ddc) {
+		if (drm_probe_ddc(dvi->ddc))
+			return connector_status_connected;
+		else
+			return connector_status_disconnected;
+	}
+
+	return connector_status_unknown;
+}
+
+static const struct drm_connector_funcs tfp410_con_funcs = {
+	.dpms			= drm_atomic_helper_connector_dpms,
+	.detect			= tfp410_connector_detect,
+	.fill_modes		= drm_helper_probe_single_connector_modes,
+	.destroy		= drm_connector_cleanup,
+	.reset			= drm_atomic_helper_connector_reset,
+	.atomic_duplicate_state	= drm_atomic_helper_connector_duplicate_state,
+	.atomic_destroy_state	= drm_atomic_helper_connector_destroy_state,
+};
+
+static int tfp410_attach(struct drm_bridge *bridge)
+{
+	struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
+	int ret;
+
+	if (!bridge->encoder) {
+		dev_err(dvi->dev, "Missing encoder\n");
+		return -ENODEV;
+	}
+
+	drm_connector_helper_add(&dvi->connector,
+				 &tfp410_con_helper_funcs);
+	ret = drm_connector_init(bridge->dev, &dvi->connector,
+				 &tfp410_con_funcs, DRM_MODE_CONNECTOR_HDMIA);
+	if (ret) {
+		dev_err(dvi->dev, "drm_connector_init() failed: %d\n", ret);
+		return ret;
+	}
+
+	drm_mode_connector_attach_encoder(&dvi->connector,
+					  bridge->encoder);
+
+	return 0;
+}
+
+static const struct drm_bridge_funcs tfp410_bridge_funcs = {
+	.attach		= tfp410_attach,
+};
+
+static int tfp410_get_connector_ddc(struct tfp410 *dvi)
+{
+	struct device_node *ep = NULL, *connector_node = NULL;
+	struct device_node *ddc_phandle = NULL;
+	int ret = 0;
+
+	/* port@1 is the connector node */
+	ep = of_graph_get_endpoint_by_regs(dvi->dev->of_node, 1, -1);
+	if (!ep)
+		goto fail;
+
+	connector_node = of_graph_get_remote_port_parent(ep);
+	if (!connector_node)
+		goto fail;
+
+	ddc_phandle = of_parse_phandle(connector_node, "ddc-i2c-bus", 0);
+	if (!ddc_phandle)
+		goto fail;
+
+	dvi->ddc = of_get_i2c_adapter_by_node(ddc_phandle);
+	if (dvi->ddc)
+		dev_info(dvi->dev, "Connector's ddc i2c bus found\n");
+	else
+		ret = -EPROBE_DEFER;
+
+fail:
+	of_node_put(ep);
+	of_node_put(connector_node);
+	of_node_put(ddc_phandle);
+	return ret;
+}
+
+static int tfp410_probe(struct platform_device *pdev)
+{
+	struct tfp410 *dvi;
+	int ret;
+
+	if (!pdev->dev.of_node) {
+		dev_err(&pdev->dev, "device-tree data is missing\n");
+		return -ENXIO;
+	}
+
+	dvi = devm_kzalloc(&pdev->dev, sizeof(*dvi), GFP_KERNEL);
+	if (!dvi)
+		return -ENOMEM;
+	platform_set_drvdata(pdev, dvi);
+
+	dvi->bridge.funcs = &tfp410_bridge_funcs;
+	dvi->bridge.of_node = pdev->dev.of_node;
+	dvi->dev = &pdev->dev;
+
+	ret = tfp410_get_connector_ddc(dvi);
+	if (ret)
+		goto fail;
+
+	ret = drm_bridge_add(&dvi->bridge);
+	if (ret) {
+		dev_err(&pdev->dev, "drm_bridge_add() failed: %d\n", ret);
+		goto fail;
+	}
+
+	return 0;
+fail:
+	i2c_put_adapter(dvi->ddc);
+	return ret;
+}
+
+static int tfp410_remove(struct platform_device *pdev)
+{
+	struct tfp410 *dvi = platform_get_drvdata(pdev);
+
+	drm_bridge_remove(&dvi->bridge);
+
+	if (dvi->ddc)
+		i2c_put_adapter(dvi->ddc);
+
+	return 0;
+}
+
+static const struct of_device_id tfp410_match[] = {
+	{ .compatible = "ti,tfp410" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, tfp410_match);
+
+struct platform_driver tfp410_driver = {
+	.probe	= tfp410_probe,
+	.remove	= tfp410_remove,
+	.driver	= {
+		.name		= "tfp410-bridge",
+		.of_match_table	= tfp410_match,
+	},
+};
+module_platform_driver(tfp410_driver);
+
+MODULE_AUTHOR("Jyri Sarha <jsarha@xxxxxx>");
+MODULE_DESCRIPTION("TI TFP410 DVI bridge driver");
+MODULE_LICENSE("GPL");
-- 
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]
  Powered by Linux