[deliverable/linux.git] / drivers / usb / core / usb-acpi.c

/*
 * 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_check_upc(struct usb_device *udev, acpi_handle handle)
{
	acpi_status status;
	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
	union acpi_object *upc;
	int ret = 0;

	status = acpi_evaluate_object(handle, "_UPC", NULL, &buffer);

	if (ACPI_FAILURE(status))
		return -ENODEV;

	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)
		udev->removable = USB_DEVICE_REMOVABLE;
	else
		udev->removable = USB_DEVICE_FIXED;

out:
	kfree(upc);
	return ret;
}

static int usb_acpi_check_pld(struct usb_device *udev, acpi_handle handle)
{
	acpi_status status;
	struct acpi_pld pld;

	status = acpi_get_physical_device_location(handle, &pld);

	if (ACPI_FAILURE(status))
		return -ENODEV;

	if (pld.user_visible)
		udev->removable = USB_DEVICE_REMOVABLE;
	else
		udev->removable = USB_DEVICE_FIXED;

	return 0;
}

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)
			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;
		}
	} else
		return -ENODEV;

	/*
	 * PLD will tell us whether a port is removable to the user or
	 * not. If we don't get an answer from PLD (it's not present
	 * or it's malformed) then try to infer it from UPC. If a
	 * device isn't connectable then it's probably not removable.
	 */
	if (usb_acpi_check_pld(udev, *handle) != 0)
		usb_acpi_check_upc(udev, *handle);

	return 0;
}

static struct acpi_bus_type usb_acpi_bus = {
	.bus = &usb_bus_type,
	.find_bridge = usb_acpi_find_device,
	.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);
}
Commit	Line	Data
da0af6e7 MG	1	/*
	2	* USB-ACPI glue code
	3	*
	4	* Copyright 2012 Red Hat <mjg@redhat.com>
	5	*
	6	* This program is free software; you can redistribute it and/or modify it
	7	* under the terms of the GNU General Public License as published by the Free
	8	* Software Foundation, version 2.
	9	*
	10	*/
	11	#include <linux/module.h>
	12	#include <linux/usb.h>
	13	#include <linux/device.h>
	14	#include <linux/errno.h>
	15	#include <linux/kernel.h>
	16	#include <linux/acpi.h>
	17	#include <linux/pci.h>
	18	#include <acpi/acpi_bus.h>
	19
	20	#include "usb.h"
	21
54d3f8c6 MG	22	static int usb_acpi_check_upc(struct usb_device *udev, acpi_handle handle)
	23	{
	24	acpi_status status;
	25	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
	26	union acpi_object *upc;
	27	int ret = 0;
	28
	29	status = acpi_evaluate_object(handle, "_UPC", NULL, &buffer);
	30
	31	if (ACPI_FAILURE(status))
	32	return -ENODEV;
	33
	34	upc = buffer.pointer;
	35
	36	if (!upc \|\| (upc->type != ACPI_TYPE_PACKAGE)
	37	\|\| upc->package.count != 4) {
	38	ret = -EINVAL;
	39	goto out;
	40	}
	41
	42	if (upc->package.elements[0].integer.value)
	43	udev->removable = USB_DEVICE_REMOVABLE;
	44	else
	45	udev->removable = USB_DEVICE_FIXED;
	46
	47	out:
	48	kfree(upc);
	49	return ret;
	50	}
	51
	52	static int usb_acpi_check_pld(struct usb_device *udev, acpi_handle handle)
	53	{
	54	acpi_status status;
	55	struct acpi_pld pld;
	56
	57	status = acpi_get_physical_device_location(handle, &pld);
	58
	59	if (ACPI_FAILURE(status))
	60	return -ENODEV;
	61
	62	if (pld.user_visible)
	63	udev->removable = USB_DEVICE_REMOVABLE;
	64	else
	65	udev->removable = USB_DEVICE_FIXED;
	66
	67	return 0;
	68	}
	69
da0af6e7 MG	70	static int usb_acpi_find_device(struct device dev, acpi_handle handle)
	71	{
	72	struct usb_device *udev;
da0af6e7	73	acpi_handle *parent_handle;
d5575424	74	int port_num;
da0af6e7	75
d5575424 LT	76	/*
	77	* In the ACPI DSDT table, only usb root hub and usb ports are
	78	* acpi device nodes. The hierarchy like following.
	79	* Device (EHC1)
	80	* Device (HUBN)
	81	* Device (PR01)
	82	* Device (PR11)
	83	* Device (PR12)
	84	* Device (PR13)
	85	* ...
	86	* So all binding process is divided into two parts. binding
	87	* root hub and usb ports.
	88	*/
	89	if (is_usb_device(dev)) {
	90	udev = to_usb_device(dev);
	91	if (udev->parent)
	92	return -ENODEV;
	93	/* root hub's parent is the usb hcd. */
	94	parent_handle = DEVICE_ACPI_HANDLE(dev->parent);
	95	*handle = acpi_get_child(parent_handle, udev->portnum);
	96	if (!*handle)
	97	return -ENODEV;
	98	return 0;
	99	} else if (is_usb_port(dev)) {
	100	sscanf(dev_name(dev), "port%d", &port_num);
	101	/* Get the struct usb_device point of port's hub */
	102	udev = to_usb_device(dev->parent->parent);
	103
	104	/*
	105	* The root hub ports' parent is the root hub. The non-root-hub
	106	* ports' parent is the parent hub port which the hub is
	107	* connected to.
	108	*/
	109	if (!udev->parent) {
	110	*handle = acpi_get_child(DEVICE_ACPI_HANDLE(&udev->dev),
	111	port_num);
	112	if (!*handle)
	113	return -ENODEV;
	114	} else {
	115	parent_handle =
	116	usb_get_hub_port_acpi_handle(udev->parent,
	117	udev->portnum);
	118	if (!parent_handle)
	119	return -ENODEV;
	120
	121	*handle = acpi_get_child(parent_handle, port_num);
	122	if (!*handle)
	123	return -ENODEV;
	124	}
	125	} else
da0af6e7 MG	126	return -ENODEV;
da0af6e7 MG	127
54d3f8c6 MG	128	/*
	129	* PLD will tell us whether a port is removable to the user or
	130	* not. If we don't get an answer from PLD (it's not present
	131	* or it's malformed) then try to infer it from UPC. If a
	132	* device isn't connectable then it's probably not removable.
	133	*/
	134	if (usb_acpi_check_pld(udev, *handle) != 0)
	135	usb_acpi_check_upc(udev, *handle);
	136
da0af6e7 MG	137	return 0;
	138	}
	139
	140	static struct acpi_bus_type usb_acpi_bus = {
	141	.bus = &usb_bus_type,
d5575424	142	.find_bridge = usb_acpi_find_device,
da0af6e7 MG	143	.find_device = usb_acpi_find_device,
	144	};
	145
	146	int usb_acpi_register(void)
	147	{
	148	return register_acpi_bus_type(&usb_acpi_bus);
	149	}
	150
	151	void usb_acpi_unregister(void)
	152	{
	153	unregister_acpi_bus_type(&usb_acpi_bus);
	154	}