1 files changed, 146 insertions, 41 deletions

diff --git a/drivers/usb/core/of.c b/drivers/usb/core/of.c
index 3863bb1ce8c5..763e4122ed5b 100644
--- a/drivers/usb/core/of.c
+++ b/drivers/usb/core/of.c
@@ -1,75 +1,180 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * of.c		The helpers for hcd device tree support
  *
  * Copyright (C) 2016 Freescale Semiconductor, Inc.
- * Author: Peter Chen <peter.chen@freescale.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  of
- * the License 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/>.
+ *	Author: Peter Chen <peter.chen@freescale.com>
+ * Copyright (C) 2017 Johan Hovold <johan@kernel.org>
  */
 
 #include <linux/of.h>
-#include <linux/of_platform.h>
+#include <linux/of_graph.h>
 #include <linux/usb/of.h>
 
 /**
- * usb_of_get_child_node - Find the device node match port number
- * @parent: the parent device node
- * @portnum: the port number which device is connecting
+ * usb_of_get_device_node() - get a USB device node
+ * @hub: hub to which device is connected
+ * @port1: one-based index of port
  *
- * Find the node from device tree according to its port number.
+ * Look up the node of a USB device given its parent hub device and one-based
+ * port number.
  *
  * Return: A pointer to the node with incremented refcount if found, or
  * %NULL otherwise.
  */
-struct device_node *usb_of_get_child_node(struct device_node *parent,
-					int portnum)
+struct device_node *usb_of_get_device_node(struct usb_device *hub, int port1)
 {
 	struct device_node *node;
-	u32 port;
+	u32 reg;
 
-	for_each_child_of_node(parent, node) {
-		if (!of_property_read_u32(node, "reg", &port)) {
-			if (port == portnum)
-				return node;
-		}
+	for_each_child_of_node(hub->dev.of_node, node) {
+		if (of_property_read_u32(node, "reg", &reg))
+			continue;
+
+		if (reg == port1)
+			return node;
 	}
 
 	return NULL;
 }
-EXPORT_SYMBOL_GPL(usb_of_get_child_node);
+EXPORT_SYMBOL_GPL(usb_of_get_device_node);
 
 /**
- * usb_of_get_companion_dev - Find the companion device
- * @dev: the device pointer to find a companion
+ * usb_of_has_combined_node() - determine whether a device has a combined node
+ * @udev: USB device
  *
- * Find the companion device from platform bus.
+ * Determine whether a USB device has a so called combined node which is
+ * shared with its sole interface. This is the case if and only if the device
+ * has a node and its descriptors report the following:
  *
- * Takes a reference to the returned struct device which needs to be dropped
- * after use.
+ *	1) bDeviceClass is 0 or 9, and
+ *	2) bNumConfigurations is 1, and
+ *	3) bNumInterfaces is 1.
  *
- * Return: On success, a pointer to the companion device, %NULL on failure.
+ * Return: True iff the device has a device node and its descriptors match the
+ * criteria for a combined node.
  */
-struct device *usb_of_get_companion_dev(struct device *dev)
+bool usb_of_has_combined_node(struct usb_device *udev)
+{
+	struct usb_device_descriptor *ddesc = &udev->descriptor;
+	struct usb_config_descriptor *cdesc;
+
+	if (!udev->dev.of_node)
+		return false;
+
+	switch (ddesc->bDeviceClass) {
+	case USB_CLASS_PER_INTERFACE:
+	case USB_CLASS_HUB:
+		if (ddesc->bNumConfigurations == 1) {
+			cdesc = &udev->config->desc;
+			if (cdesc->bNumInterfaces == 1)
+				return true;
+		}
+	}
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(usb_of_has_combined_node);
+
+static bool usb_of_has_devices_or_graph(const struct usb_device *hub)
+{
+	const struct device_node *np = hub->dev.of_node;
+	struct device_node *child;
+
+	if (of_graph_is_present(np))
+		return true;
+
+	for_each_child_of_node(np, child) {
+		if (of_property_present(child, "reg")) {
+			of_node_put(child);
+			return true;
+		}
+	}
+
+	return false;
+}
+
+/**
+ * usb_of_get_connect_type() - get a USB hub's port connect_type
+ * @hub: hub to which port is for @port1
+ * @port1: one-based index of port
+ *
+ * Get the connect_type of @port1 based on the device node for @hub. If the
+ * port is described in the OF graph, the connect_type is "hotplug". If the
+ * @hub has a child device has with a 'reg' property equal to @port1 the
+ * connect_type is "hard-wired". If there isn't an OF graph or child node at
+ * all then the connect_type is "unknown". Otherwise, the port is considered
+ * "unused" because it isn't described at all.
+ *
+ * Return: A connect_type for @port1 based on the device node for @hub.
+ */
+enum usb_port_connect_type usb_of_get_connect_type(struct usb_device *hub, int port1)
+{
+	struct device_node *np, *child, *ep, *remote_np;
+	enum usb_port_connect_type connect_type;
+
+	/* Only set connect_type if binding has ports/hardwired devices. */
+	if (!usb_of_has_devices_or_graph(hub))
+		return USB_PORT_CONNECT_TYPE_UNKNOWN;
+
+	/* Assume port is unused if there's a graph or a child node. */
+	connect_type = USB_PORT_NOT_USED;
+
+	np = hub->dev.of_node;
+	/*
+	 * Hotplug ports are connected to an available remote node, e.g.
+	 * usb-a-connector compatible node, in the OF graph.
+	 */
+	if (of_graph_is_present(np)) {
+		ep = of_graph_get_endpoint_by_regs(np, port1, -1);
+		if (ep) {
+			remote_np = of_graph_get_remote_port_parent(ep);
+			of_node_put(ep);
+			if (of_device_is_available(remote_np))
+				connect_type = USB_PORT_CONNECT_TYPE_HOT_PLUG;
+			of_node_put(remote_np);
+		}
+	}
+
+	/*
+	 * Hard-wired ports are child nodes with a reg property corresponding
+	 * to the port number, i.e. a usb device.
+	 */
+	child = usb_of_get_device_node(hub, port1);
+	if (of_device_is_available(child))
+		connect_type = USB_PORT_CONNECT_TYPE_HARD_WIRED;
+	of_node_put(child);
+
+	return connect_type;
+}
+EXPORT_SYMBOL_GPL(usb_of_get_connect_type);
+
+/**
+ * usb_of_get_interface_node() - get a USB interface node
+ * @udev: USB device of interface
+ * @config: configuration value
+ * @ifnum: interface number
+ *
+ * Look up the node of a USB interface given its USB device, configuration
+ * value and interface number.
+ *
+ * Return: A pointer to the node with incremented refcount if found, or
+ * %NULL otherwise.
+ */
+struct device_node *
+usb_of_get_interface_node(struct usb_device *udev, u8 config, u8 ifnum)
 {
 	struct device_node *node;
-	struct platform_device *pdev = NULL;
+	u32 reg[2];
 
-	node = of_parse_phandle(dev->of_node, "companion", 0);
-	if (node)
-		pdev = of_find_device_by_node(node);
+	for_each_child_of_node(udev->dev.of_node, node) {
+		if (of_property_read_u32_array(node, "reg", reg, 2))
+			continue;
 
-	of_node_put(node);
+		if (reg[0] == ifnum && reg[1] == config)
+			return node;
+	}
 
-	return pdev ? &pdev->dev : NULL;
+	return NULL;
 }
-EXPORT_SYMBOL_GPL(usb_of_get_companion_dev);
+EXPORT_SYMBOL_GPL(usb_of_get_interface_node);