usb: Bind devices to ACPI devices when possible

Built-in USB devices will typically have a representation in the system
ACPI tables. Add support for binding the two together so the USB code can
make use of the associated methods.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Matthew Garrett 2012-05-11 16:08:27 +08:00 committed by Greg Kroah-Hartman
parent 38ac0f1b90
commit da0af6e78e
4 changed files with 74 additions and 0 deletions

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@ -9,5 +9,6 @@ usbcore-y += config.o file.o buffer.o sysfs.o endpoint.o
usbcore-y += devio.o notify.o generic.o quirks.o devices.o
usbcore-$(CONFIG_PCI) += hcd-pci.o
usbcore-$(CONFIG_ACPI) += usb-acpi.o
obj-$(CONFIG_USB) += usbcore.o

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@ -0,0 +1,60 @@
/*
* 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 <acpi/acpi_bus.h>
#include "usb.h"
static int usb_acpi_find_device(struct device *dev, acpi_handle *handle)
{
struct usb_device *udev;
struct device *parent;
acpi_handle *parent_handle;
if (!is_usb_device(dev))
return -ENODEV;
udev = to_usb_device(dev);
parent = dev->parent;
parent_handle = DEVICE_ACPI_HANDLE(parent);
if (!parent_handle)
return -ENODEV;
*handle = acpi_get_child(parent_handle, udev->portnum);
if (!*handle)
return -ENODEV;
return 0;
}
static struct acpi_bus_type usb_acpi_bus = {
.bus = &usb_bus_type,
.find_bridge = NULL,
.find_device = usb_acpi_find_device,
};
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);
}

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@ -1015,6 +1015,9 @@ static int __init usb_init(void)
if (retval)
goto out;
retval = usb_acpi_register();
if (retval)
goto acpi_register_failed;
retval = bus_register(&usb_bus_type);
if (retval)
goto bus_register_failed;
@ -1049,6 +1052,8 @@ static int __init usb_init(void)
bus_notifier_failed:
bus_unregister(&usb_bus_type);
bus_register_failed:
usb_acpi_unregister();
acpi_register_failed:
usb_debugfs_cleanup();
out:
return retval;
@ -1070,6 +1075,7 @@ static void __exit usb_exit(void)
usb_hub_cleanup();
bus_unregister_notifier(&usb_bus_type, &usb_bus_nb);
bus_unregister(&usb_bus_type);
usb_acpi_unregister();
usb_debugfs_cleanup();
}

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@ -156,3 +156,10 @@ extern void usb_notify_remove_device(struct usb_device *udev);
extern void usb_notify_add_bus(struct usb_bus *ubus);
extern void usb_notify_remove_bus(struct usb_bus *ubus);
#ifdef CONFIG_ACPI
extern int usb_acpi_register(void);
extern void usb_acpi_unregister(void);
#else
static inline int usb_acpi_register(void) { return 0; };
static inline void usb_acpi_unregister(void) { };
#endif