1 files changed, 228 insertions, 0 deletions
diff --git a/drivers/usb/core/usb-acpi.c b/drivers/usb/core/usb-acpi.c
new file mode 100644
index 00000000000..2776cfe64c0
--- /dev/null
+++ b/drivers/usb/core/usb-acpi.c
@@ -0,0 +1,228 @@
+/*
+ * USB-ACPI glue code
+ *
+ * Copyright 2012 Red Hat <mjg@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation, version 2.
+ *
+ */
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/acpi.h>
+#include <linux/pci.h>
+#include <linux/usb/hcd.h>
+
+#include "hub.h"
+
+/**
+ * usb_acpi_power_manageable - check whether usb port has
+ * acpi power resource.
+ * @hdev: USB device belonging to the usb hub
+ * @index: port index based zero
+ *
+ * Return true if the port has acpi power resource and false if no.
+ */
+bool usb_acpi_power_manageable(struct usb_device *hdev, int index)
+{
+	acpi_handle port_handle;
+	int port1 = index + 1;
+
+	port_handle = usb_get_hub_port_acpi_handle(hdev,
+		port1);
+	if (port_handle)
+		return acpi_bus_power_manageable(port_handle);
+	else
+		return false;
+}
+EXPORT_SYMBOL_GPL(usb_acpi_power_manageable);
+
+/**
+ * usb_acpi_set_power_state - control usb port's power via acpi power
+ * resource
+ * @hdev: USB device belonging to the usb hub
+ * @index: port index based zero
+ * @enable: power state expected to be set
+ *
+ * Notice to use usb_acpi_power_manageable() to check whether the usb port
+ * has acpi power resource before invoking this function.
+ *
+ * Returns 0 on success, else negative errno.
+ */
+int usb_acpi_set_power_state(struct usb_device *hdev, int index, bool enable)
+{
+	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
+	struct usb_port *port_dev;
+	acpi_handle port_handle;
+	unsigned char state;
+	int port1 = index + 1;
+	int error = -EINVAL;
+
+	if (!hub)
+		return -ENODEV;
+	port_dev = hub->ports[port1 - 1];
+
+	port_handle = (acpi_handle) usb_get_hub_port_acpi_handle(hdev, port1);
+	if (!port_handle)
+		return error;
+
+	if (enable)
+		state = ACPI_STATE_D0;
+	else
+		state = ACPI_STATE_D3_COLD;
+
+	error = acpi_bus_set_power(port_handle, state);
+	if (!error)
+		dev_dbg(&port_dev->dev, "acpi: power was set to %d\n", enable);
+	else
+		dev_dbg(&port_dev->dev, "acpi: power failed to be set\n");
+
+	return error;
+}
+EXPORT_SYMBOL_GPL(usb_acpi_set_power_state);
+
+static enum usb_port_connect_type usb_acpi_get_connect_type(acpi_handle handle,
+		struct acpi_pld_info *pld)
+{
+	enum usb_port_connect_type connect_type = USB_PORT_CONNECT_TYPE_UNKNOWN;
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+	union acpi_object *upc;
+	acpi_status status;
+
+	/*
+	 * According to ACPI Spec 9.13. PLD indicates whether usb port is
+	 * user visible and _UPC indicates whether it is connectable. If
+	 * the port was visible and connectable, it could be freely connected
+	 * and disconnected with USB devices. If no visible and connectable,
+	 * a usb device is directly hard-wired to the port. If no visible and
+	 * no connectable, the port would be not used.
+	 */
+	status = acpi_evaluate_object(handle, "_UPC", NULL, &buffer);
+	upc = buffer.pointer;
+	if (!upc || (upc->type != ACPI_TYPE_PACKAGE)
+		|| upc->package.count != 4) {
+		goto out;
+	}
+
+	if (upc->package.elements[0].integer.value)
+		if (pld->user_visible)
+			connect_type = USB_PORT_CONNECT_TYPE_HOT_PLUG;
+		else
+			connect_type = USB_PORT_CONNECT_TYPE_HARD_WIRED;
+	else if (!pld->user_visible)
+		connect_type = USB_PORT_NOT_USED;
+out:
+	kfree(upc);
+	return connect_type;
+}
+
+
+/*
+ * Private to usb-acpi, all the core needs to know is that
+ * port_dev->location is non-zero when it has been set by the firmware.
+ */
+#define USB_ACPI_LOCATION_VALID (1 << 31)
+
+static struct acpi_device *usb_acpi_find_companion(struct device *dev)
+{
+	struct usb_device *udev;
+	struct acpi_device *adev;
+	acpi_handle *parent_handle;
+
+	/*
+	 * In the ACPI DSDT table, only usb root hub and usb ports are
+	 * acpi device nodes. The hierarchy like following.
+	 * Device (EHC1)
+	 *	Device (HUBN)
+	 *		Device (PR01)
+	 *			Device (PR11)
+	 *			Device (PR12)
+	 *			Device (PR13)
+	 *			...
+	 * So all binding process is divided into two parts. binding
+	 * root hub and usb ports.
+	 */
+	if (is_usb_device(dev)) {
+		udev = to_usb_device(dev);
+		if (udev->parent)
+			return NULL;
+
+		/* root hub is only child (_ADR=0) under its parent, the HC */
+		adev = ACPI_COMPANION(dev->parent);
+		return acpi_find_child_device(adev, 0, false);
+	} else if (is_usb_port(dev)) {
+		struct usb_port *port_dev = to_usb_port(dev);
+		int port1 = port_dev->portnum;
+		struct acpi_pld_info *pld;
+		acpi_handle *handle;
+		acpi_status status;
+
+		/* Get the struct usb_device point of port's hub */
+		udev = to_usb_device(dev->parent->parent);
+
+		/*
+		 * The root hub ports' parent is the root hub. The non-root-hub
+		 * ports' parent is the parent hub port which the hub is
+		 * connected to.
+		 */
+		if (!udev->parent) {
+			struct usb_hcd *hcd = bus_to_hcd(udev->bus);
+			int raw;
+
+			raw = usb_hcd_find_raw_port_number(hcd, port1);
+			adev = acpi_find_child_device(ACPI_COMPANION(&udev->dev),
+					raw, false);
+			if (!adev)
+				return NULL;
+		} else {
+			parent_handle =
+				usb_get_hub_port_acpi_handle(udev->parent,
+				udev->portnum);
+			if (!parent_handle)
+				return NULL;
+
+			acpi_bus_get_device(parent_handle, &adev);
+			adev = acpi_find_child_device(adev, port1, false);
+			if (!adev)
+				return NULL;
+		}
+		handle = adev->handle;
+		status = acpi_get_physical_device_location(handle, &pld);
+		if (ACPI_FAILURE(status) || !pld)
+			return adev;
+
+		port_dev->location = USB_ACPI_LOCATION_VALID
+			| pld->group_token << 8 | pld->group_position;
+		port_dev->connect_type = usb_acpi_get_connect_type(handle, pld);
+		ACPI_FREE(pld);
+
+		return adev;
+	}
+
+	return NULL;
+}
+
+static bool usb_acpi_bus_match(struct device *dev)
+{
+	return is_usb_device(dev) || is_usb_port(dev);
+}
+
+static struct acpi_bus_type usb_acpi_bus = {
+	.name = "USB",
+	.match = usb_acpi_bus_match,
+	.find_companion = usb_acpi_find_companion,
+};
+
+int usb_acpi_register(void)
+{
+	return register_acpi_bus_type(&usb_acpi_bus);
+}
+
+void usb_acpi_unregister(void)
+{
+	unregister_acpi_bus_type(&usb_acpi_bus);
+}