Loading...
Note: File does not exist in v3.1.
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * USB-ACPI glue code
4 *
5 * Copyright 2012 Red Hat <mjg@redhat.com>
6 */
7#include <linux/module.h>
8#include <linux/usb.h>
9#include <linux/device.h>
10#include <linux/errno.h>
11#include <linux/kernel.h>
12#include <linux/acpi.h>
13#include <linux/pci.h>
14#include <linux/usb/hcd.h>
15
16#include "hub.h"
17
18/**
19 * usb_acpi_power_manageable - check whether usb port has
20 * acpi power resource.
21 * @hdev: USB device belonging to the usb hub
22 * @index: port index based zero
23 *
24 * Return true if the port has acpi power resource and false if no.
25 */
26bool usb_acpi_power_manageable(struct usb_device *hdev, int index)
27{
28 acpi_handle port_handle;
29 int port1 = index + 1;
30
31 port_handle = usb_get_hub_port_acpi_handle(hdev,
32 port1);
33 if (port_handle)
34 return acpi_bus_power_manageable(port_handle);
35 else
36 return false;
37}
38EXPORT_SYMBOL_GPL(usb_acpi_power_manageable);
39
40/**
41 * usb_acpi_set_power_state - control usb port's power via acpi power
42 * resource
43 * @hdev: USB device belonging to the usb hub
44 * @index: port index based zero
45 * @enable: power state expected to be set
46 *
47 * Notice to use usb_acpi_power_manageable() to check whether the usb port
48 * has acpi power resource before invoking this function.
49 *
50 * Returns 0 on success, else negative errno.
51 */
52int usb_acpi_set_power_state(struct usb_device *hdev, int index, bool enable)
53{
54 struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
55 struct usb_port *port_dev;
56 acpi_handle port_handle;
57 unsigned char state;
58 int port1 = index + 1;
59 int error = -EINVAL;
60
61 if (!hub)
62 return -ENODEV;
63 port_dev = hub->ports[port1 - 1];
64
65 port_handle = (acpi_handle) usb_get_hub_port_acpi_handle(hdev, port1);
66 if (!port_handle)
67 return error;
68
69 if (enable)
70 state = ACPI_STATE_D0;
71 else
72 state = ACPI_STATE_D3_COLD;
73
74 error = acpi_bus_set_power(port_handle, state);
75 if (!error)
76 dev_dbg(&port_dev->dev, "acpi: power was set to %d\n", enable);
77 else
78 dev_dbg(&port_dev->dev, "acpi: power failed to be set\n");
79
80 return error;
81}
82EXPORT_SYMBOL_GPL(usb_acpi_set_power_state);
83
84static enum usb_port_connect_type usb_acpi_get_connect_type(acpi_handle handle,
85 struct acpi_pld_info *pld)
86{
87 enum usb_port_connect_type connect_type = USB_PORT_CONNECT_TYPE_UNKNOWN;
88 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
89 union acpi_object *upc;
90 acpi_status status;
91
92 /*
93 * According to 9.14 in ACPI Spec 6.2. _PLD indicates whether usb port
94 * is user visible and _UPC indicates whether it is connectable. If
95 * the port was visible and connectable, it could be freely connected
96 * and disconnected with USB devices. If no visible and connectable,
97 * a usb device is directly hard-wired to the port. If no visible and
98 * no connectable, the port would be not used.
99 */
100 status = acpi_evaluate_object(handle, "_UPC", NULL, &buffer);
101 upc = buffer.pointer;
102 if (!upc || (upc->type != ACPI_TYPE_PACKAGE)
103 || upc->package.count != 4) {
104 goto out;
105 }
106
107 if (upc->package.elements[0].integer.value)
108 if (pld->user_visible)
109 connect_type = USB_PORT_CONNECT_TYPE_HOT_PLUG;
110 else
111 connect_type = USB_PORT_CONNECT_TYPE_HARD_WIRED;
112 else if (!pld->user_visible)
113 connect_type = USB_PORT_NOT_USED;
114out:
115 kfree(upc);
116 return connect_type;
117}
118
119
120/*
121 * Private to usb-acpi, all the core needs to know is that
122 * port_dev->location is non-zero when it has been set by the firmware.
123 */
124#define USB_ACPI_LOCATION_VALID (1 << 31)
125
126static struct acpi_device *usb_acpi_find_port(struct acpi_device *parent,
127 int raw)
128{
129 struct acpi_device *adev;
130
131 if (!parent)
132 return NULL;
133
134 list_for_each_entry(adev, &parent->children, node) {
135 if (acpi_device_adr(adev) == raw)
136 return adev;
137 }
138
139 return acpi_find_child_device(parent, raw, false);
140}
141
142static struct acpi_device *
143usb_acpi_get_companion_for_port(struct usb_port *port_dev)
144{
145 struct usb_device *udev;
146 struct acpi_device *adev;
147 acpi_handle *parent_handle;
148 int port1;
149
150 /* Get the struct usb_device point of port's hub */
151 udev = to_usb_device(port_dev->dev.parent->parent);
152
153 /*
154 * The root hub ports' parent is the root hub. The non-root-hub
155 * ports' parent is the parent hub port which the hub is
156 * connected to.
157 */
158 if (!udev->parent) {
159 adev = ACPI_COMPANION(&udev->dev);
160 port1 = usb_hcd_find_raw_port_number(bus_to_hcd(udev->bus),
161 port_dev->portnum);
162 } else {
163 parent_handle = usb_get_hub_port_acpi_handle(udev->parent,
164 udev->portnum);
165 if (!parent_handle)
166 return NULL;
167
168 acpi_bus_get_device(parent_handle, &adev);
169 port1 = port_dev->portnum;
170 }
171
172 return usb_acpi_find_port(adev, port1);
173}
174
175static struct acpi_device *
176usb_acpi_find_companion_for_port(struct usb_port *port_dev)
177{
178 struct acpi_device *adev;
179 struct acpi_pld_info *pld;
180 acpi_handle *handle;
181 acpi_status status;
182
183 adev = usb_acpi_get_companion_for_port(port_dev);
184 if (!adev)
185 return NULL;
186
187 handle = adev->handle;
188 status = acpi_get_physical_device_location(handle, &pld);
189 if (!ACPI_FAILURE(status) && pld) {
190 port_dev->location = USB_ACPI_LOCATION_VALID
191 | pld->group_token << 8 | pld->group_position;
192 port_dev->connect_type = usb_acpi_get_connect_type(handle, pld);
193 ACPI_FREE(pld);
194 }
195
196 return adev;
197}
198
199static struct acpi_device *
200usb_acpi_find_companion_for_device(struct usb_device *udev)
201{
202 struct acpi_device *adev;
203 struct usb_port *port_dev;
204 struct usb_hub *hub;
205
206 if (!udev->parent) {
207 /* root hub is only child (_ADR=0) under its parent, the HC */
208 adev = ACPI_COMPANION(udev->dev.parent);
209 return acpi_find_child_device(adev, 0, false);
210 }
211
212 hub = usb_hub_to_struct_hub(udev->parent);
213 if (!hub)
214 return NULL;
215
216 /*
217 * This is an embedded USB device connected to a port and such
218 * devices share port's ACPI companion.
219 */
220 port_dev = hub->ports[udev->portnum - 1];
221 return usb_acpi_get_companion_for_port(port_dev);
222}
223
224static struct acpi_device *usb_acpi_find_companion(struct device *dev)
225{
226 /*
227 * The USB hierarchy like following:
228 *
229 * Device (EHC1)
230 * Device (HUBN)
231 * Device (PR01)
232 * Device (PR11)
233 * Device (PR12)
234 * Device (FN12)
235 * Device (FN13)
236 * Device (PR13)
237 * ...
238 * where HUBN is root hub, and PRNN are USB ports and devices
239 * connected to them, and FNNN are individualk functions for
240 * connected composite USB devices. PRNN and FNNN may contain
241 * _CRS and other methods describing sideband resources for
242 * the connected device.
243 *
244 * On the kernel side both root hub and embedded USB devices are
245 * represented as instances of usb_device structure, and ports
246 * are represented as usb_port structures, so the whole process
247 * is split into 2 parts: finding companions for devices and
248 * finding companions for ports.
249 *
250 * Note that we do not handle individual functions of composite
251 * devices yet, for that we would need to assign companions to
252 * devices corresponding to USB interfaces.
253 */
254 if (is_usb_device(dev))
255 return usb_acpi_find_companion_for_device(to_usb_device(dev));
256 else if (is_usb_port(dev))
257 return usb_acpi_find_companion_for_port(to_usb_port(dev));
258
259 return NULL;
260}
261
262static bool usb_acpi_bus_match(struct device *dev)
263{
264 return is_usb_device(dev) || is_usb_port(dev);
265}
266
267static struct acpi_bus_type usb_acpi_bus = {
268 .name = "USB",
269 .match = usb_acpi_bus_match,
270 .find_companion = usb_acpi_find_companion,
271};
272
273int usb_acpi_register(void)
274{
275 return register_acpi_bus_type(&usb_acpi_bus);
276}
277
278void usb_acpi_unregister(void)
279{
280 unregister_acpi_bus_type(&usb_acpi_bus);
281}