platform/x86: intel_cht_int33fe: Supply fwnodes for the external dependencies

Supplying also external devices, the DisplayPort connector
and the USB role switch, software fwnodes. After this the
driver has access to all the components tied to the USB
Type-C connector and can start creating software node
references to actually associate them with the USB Type-C
connector device.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/platform/x86/intel_cht_int33fe.c

@@ -21,6 +21,7 @@
 #include <linux/i2c.h>
 #include <linux/interrupt.h>
 #include <linux/module.h>
+#include <linux/pci.h>
 #include <linux/platform_device.h>
 #include <linux/regulator/consumer.h>
 #include <linux/slab.h>
@@ -32,6 +33,8 @@ enum {
 	INT33FE_NODE_FUSB302,
 	INT33FE_NODE_MAX17047,
 	INT33FE_NODE_PI3USB30532,
+	INT33FE_NODE_DISPLAYPORT,
+	INT33FE_NODE_ROLE_SWITCH,
 	INT33FE_NODE_USB_CONNECTOR,
 	INT33FE_NODE_MAX,
 };
@@ -42,6 +45,9 @@ struct cht_int33fe_data {
 	struct i2c_client *pi3usb30532;
 	/* Contain a list-head must be per device */
 	struct device_connection connections[4];
+
+	struct fwnode_handle *dp;
+	struct fwnode_handle *mux;
 };
 
 /*
@@ -110,10 +116,126 @@ static const struct software_node nodes[] = {
 	{ "fusb302", NULL, fusb302_props },
 	{ "max17047", NULL, max17047_props },
 	{ "pi3usb30532" },
+	{ "displayport" },
+	{ "usb-role-switch" },
 	{ "connector", &nodes[0], usb_connector_props },
 	{ }
 };
 
+static int cht_int33fe_setup_mux(struct cht_int33fe_data *data)
+{
+	struct fwnode_handle *fwnode;
+	struct device *dev;
+	struct device *p;
+
+	fwnode = software_node_fwnode(&nodes[INT33FE_NODE_ROLE_SWITCH]);
+	if (!fwnode)
+		return -ENODEV;
+
+	/* First finding the platform device */
+	p = bus_find_device_by_name(&platform_bus_type, NULL,
+				    "intel_xhci_usb_sw");
+	if (!p)
+		return -EPROBE_DEFER;
+
+	/* Then the mux child device */
+	dev = device_find_child_by_name(p, "intel_xhci_usb_sw-role-switch");
+	put_device(p);
+	if (!dev)
+		return -EPROBE_DEFER;
+
+	/* If there already is a node for the mux, using that one. */
+	if (dev->fwnode)
+		fwnode_remove_software_node(fwnode);
+	else
+		dev->fwnode = fwnode;
+
+	data->mux = fwnode_handle_get(dev->fwnode);
+	put_device(dev);
+
+	return 0;
+}
+
+static int cht_int33fe_setup_dp(struct cht_int33fe_data *data)
+{
+	struct fwnode_handle *fwnode;
+	struct pci_dev *pdev;
+
+	fwnode = software_node_fwnode(&nodes[INT33FE_NODE_DISPLAYPORT]);
+	if (!fwnode)
+		return -ENODEV;
+
+	/* First let's find the GPU PCI device */
+	pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
+	if (!pdev || pdev->vendor != PCI_VENDOR_ID_INTEL) {
+		pci_dev_put(pdev);
+		return -ENODEV;
+	}
+
+	/* Then the DP child device node */
+	data->dp = device_get_named_child_node(&pdev->dev, "DD02");
+	pci_dev_put(pdev);
+	if (!data->dp)
+		return -ENODEV;
+
+	fwnode->secondary = ERR_PTR(-ENODEV);
+	data->dp->secondary = fwnode;
+
+	return 0;
+}
+
+static void cht_int33fe_remove_nodes(struct cht_int33fe_data *data)
+{
+	software_node_unregister_nodes(nodes);
+
+	if (data->mux) {
+		fwnode_handle_put(data->mux);
+		data->mux = NULL;
+	}
+
+	if (data->dp) {
+		data->dp->secondary = NULL;
+		fwnode_handle_put(data->dp);
+		data->dp = NULL;
+	}
+}
+
+static int cht_int33fe_add_nodes(struct cht_int33fe_data *data)
+{
+	int ret;
+
+	ret = software_node_register_nodes(nodes);
+	if (ret)
+		return ret;
+
+	/* The devices that are not created in this driver need extra steps. */
+
+	/*
+	 * There is no ACPI device node for the USB role mux, so we need to find
+	 * the mux device and assign our node directly to it. That means we
+	 * depend on the mux driver. This function will return -PROBE_DEFER
+	 * until the mux device is registered.
+	 */
+	ret = cht_int33fe_setup_mux(data);
+	if (ret)
+		goto err_remove_nodes;
+
+	/*
+	 * The DP connector does have ACPI device node. In this case we can just
+	 * find that ACPI node and assign our node as the secondary node to it.
+	 */
+	ret = cht_int33fe_setup_dp(data);
+	if (ret)
+		goto err_remove_nodes;
+
+	return 0;
+
+err_remove_nodes:
+	cht_int33fe_remove_nodes(data);
+
+	return ret;
+}
+
 static int
 cht_int33fe_register_max17047(struct device *dev, struct cht_int33fe_data *data)
 {
@@ -212,7 +334,7 @@ static int cht_int33fe_probe(struct platform_device *pdev)
 	if (!data)
 		return -ENOMEM;
 
-	ret = software_node_register_nodes(nodes);
+	ret = cht_int33fe_add_nodes(data);
 	if (ret)
 		return ret;
 
@@ -281,7 +403,7 @@ static int cht_int33fe_probe(struct platform_device *pdev)
 	device_connections_remove(data->connections);
 
 out_remove_nodes:
-	software_node_unregister_nodes(nodes);
+	cht_int33fe_remove_nodes(data);
 
 	return ret;
 }
@@ -295,7 +417,7 @@ static int cht_int33fe_remove(struct platform_device *pdev)
 	i2c_unregister_device(data->max17047);
 
 	device_connections_remove(data->connections);
-	software_node_unregister_nodes(nodes);
+	cht_int33fe_remove_nodes(data);
 
 	return 0;
 }