--- /dev/null
+/*
+ * Copyright (C) 2016 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/module.h>
+#include <linux/of_graph.h>
+#include <linux/platform_device.h>
+#include <linux/i2c.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_init(struct device *dev)
+{
+ struct tfp410 *dvi;
+ int ret;
+
+ if (!dev->of_node) {
+ dev_err(dev, "device-tree data is missing\n");
+ return -ENXIO;
+ }
+
+ dvi = devm_kzalloc(dev, sizeof(*dvi), GFP_KERNEL);
+ if (!dvi)
+ return -ENOMEM;
+ dev_set_drvdata(dev, dvi);
+
+ dvi->bridge.funcs = &tfp410_bridge_funcs;
+ dvi->bridge.of_node = dev->of_node;
+ dvi->dev = dev;
+
+ ret = tfp410_get_connector_ddc(dvi);
+ if (ret)
+ goto fail;
+
+ ret = drm_bridge_add(&dvi->bridge);
+ if (ret) {
+ dev_err(dev, "drm_bridge_add() failed: %d\n", ret);
+ goto fail;
+ }
+
+ return 0;
+fail:
+ i2c_put_adapter(dvi->ddc);
+ return ret;
+}
+
+static int tfp410_fini(struct device *dev)
+{
+ struct tfp410 *dvi = dev_get_drvdata(dev);
+
+ drm_bridge_remove(&dvi->bridge);
+
+ if (dvi->ddc)
+ i2c_put_adapter(dvi->ddc);
+
+ return 0;
+}
+
+static int tfp410_probe(struct platform_device *pdev)
+{
+ return tfp410_init(&pdev->dev);
+}
+
+static int tfp410_remove(struct platform_device *pdev)
+{
+ return tfp410_fini(&pdev->dev);
+}
+
+static const struct of_device_id tfp410_match[] = {
+ { .compatible = "ti,tfp410" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, tfp410_match);
+
+struct platform_driver tfp410_platform_driver = {
+ .probe = tfp410_probe,
+ .remove = tfp410_remove,
+ .driver = {
+ .name = "tfp410-bridge",
+ .of_match_table = tfp410_match,
+ },
+};
+
+#if IS_ENABLED(CONFIG_I2C)
+/* There is currently no i2c functionality. */
+static int tfp410_i2c_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ int reg;
+
+ if (!client->dev.of_node ||
+ of_property_read_u32(client->dev.of_node, "reg", ®)) {
+ dev_err(&client->dev,
+ "Can't get i2c reg property from device-tree\n");
+ return -ENXIO;
+ }
+
+ return tfp410_init(&client->dev);
+}
+
+static int tfp410_i2c_remove(struct i2c_client *client)
+{
+ return tfp410_fini(&client->dev);
+}
+
+static const struct i2c_device_id tfp410_i2c_ids[] = {
+ { "tfp410", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids);
+
+static struct i2c_driver tfp410_i2c_driver = {
+ .driver = {
+ .name = "tfp410",
+ .of_match_table = of_match_ptr(tfp410_match),
+ },
+ .id_table = tfp410_i2c_ids,
+ .probe = tfp410_i2c_probe,
+ .remove = tfp410_i2c_remove,
+};
+#endif /* IS_ENABLED(CONFIG_I2C) */
+
+static struct {
+ uint i2c:1;
+ uint platform:1;
+} tfp410_registered_driver;
+
+static int __init tfp410_module_init(void)
+{
+ int ret;
+
+#if IS_ENABLED(CONFIG_I2C)
+ ret = i2c_add_driver(&tfp410_i2c_driver);
+ if (ret)
+ pr_err("%s: registering i2c driver failed: %d",
+ __func__, ret);
+ else
+ tfp410_registered_driver.i2c = 1;
+#endif
+
+ ret = platform_driver_register(&tfp410_platform_driver);
+ if (ret)
+ pr_err("%s: registering platform driver failed: %d",
+ __func__, ret);
+ else
+ tfp410_registered_driver.platform = 1;
+
+ if (tfp410_registered_driver.i2c ||
+ tfp410_registered_driver.platform)
+ return 0;
+
+ return ret;
+}
+module_init(tfp410_module_init);
+
+static void __exit tfp410_module_exit(void)
+{
+#if IS_ENABLED(CONFIG_I2C)
+ if (tfp410_registered_driver.i2c)
+ i2c_del_driver(&tfp410_i2c_driver);
+#endif
+ if (tfp410_registered_driver.platform)
+ platform_driver_unregister(&tfp410_platform_driver);
+}
+module_exit(tfp410_module_exit);
+
+MODULE_AUTHOR("Jyri Sarha <jsarha@ti.com>");
+MODULE_DESCRIPTION("TI TFP410 DVI bridge driver");
+MODULE_LICENSE("GPL");