/*
* 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"
/**
* 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)
{
acpi_handle port_handle;
unsigned char state;
int port1 = index + 1;
int error = -EINVAL;
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(&hdev->dev, "The power of hub port %d was set to %d\n",
port1, enable);
else
dev_dbg(&hdev->dev, "The power of hub port failed to be set\n");
return error;
}
EXPORT_SYMBOL_GPL(usb_acpi_set_power_state);
static int usb_acpi_check_port_connect_type(struct usb_device *hdev,
acpi_handle handle, int port1)
{
acpi_status status;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *upc;
struct acpi_pld_info *pld;
int ret = 0;
/*
* Accoding 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_get_physical_device_location(handle, &pld);
if (ACPI_FAILURE(status))
return -ENODEV;
status = acpi_evaluate_object(handle, "_UPC", NULL, &buffer);
upc = buffer.pointer;
if (!upc || (upc->type != ACPI_TYPE_PACKAGE)
|| upc->package.count != 4) {
ret = -EINVAL;
goto out;
}
if (upc->package.elements[0].integer.value)
if (pld->user_visible)
usb_set_hub_port_connect_type(hdev, port1,
USB_PORT_CONNECT_TYPE_HOT_PLUG);
else
usb_set_hub_port_connect_type(hdev, port1,
USB_PORT_CONNECT_TYPE_HARD_WIRED);
else if (!pld->user_visible)
usb_set_hub_port_connect_type(hdev, port1, USB_PORT_NOT_USED);
out:
ACPI_FREE(pld);
kfree(upc);
return ret;
}
static int usb_acpi_find_device(struct device *dev, acpi_handle *handle)
{
struct usb_device *udev;
acpi_handle *parent_handle;
int port_num;
/*
* 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) {
enum usb_port_connect_type type;
/*
* According usb port's connect type to set usb device's
* removability.
*/
type = usb_get_hub_port_connect_type(udev->parent,
udev->portnum);
switch (type) {
case USB_PORT_CONNECT_TYPE_HOT_PLUG:
udev->removable = USB_DEVICE_REMOVABLE;
break;
case USB_PORT_CONNECT_TYPE_HARD_WIRED:
udev->removable = USB_DEVICE_FIXED;
break;
default:
udev->removable = USB_DEVICE_REMOVABLE_UNKNOWN;
break;
}
return -ENODEV;
}
/* root hub's parent is the usb hcd. */
parent_handle = DEVICE_ACPI_HANDLE(dev->parent);
*handle = acpi_get_child(parent_handle, udev->portnum);
if (!*handle)
return -ENODEV;
return 0;
} else if (is_usb_port(dev)) {
sscanf(dev_name(dev), "port%d", &port_num);
/* 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) {
*handle = acpi_get_child(DEVICE_ACPI_HANDLE(&udev->dev),
port_num);
if (!*handle)
return -ENODEV;
} else {
parent_handle =
usb_get_hub_port_acpi_handle(udev->parent,
udev->portnum);
if (!parent_handle)
return -ENODEV;
*handle = acpi_get_child(parent_handle, port_num);
if (!*handle)
return -ENODEV;
}
usb_acpi_check_port_connect_type(udev, *handle, port_num);
} else
return -ENODEV;
return 0;
}
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_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);
}
