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 <linux/usb/hcd.h>
19
20 #include "hub.h"
21
22 /**
23 * usb_acpi_power_manageable - check whether usb port has
24 * acpi power resource.
25 * @hdev: USB device belonging to the usb hub
26 * @index: port index based zero
27 *
28 * Return true if the port has acpi power resource and false if no.
29 */
usb_acpi_power_manageable(struct usb_device * hdev,int index)30 bool usb_acpi_power_manageable(struct usb_device *hdev, int index)
31 {
32 acpi_handle port_handle;
33 int port1 = index + 1;
34
35 port_handle = usb_get_hub_port_acpi_handle(hdev,
36 port1);
37 if (port_handle)
38 return acpi_bus_power_manageable(port_handle);
39 else
40 return false;
41 }
42 EXPORT_SYMBOL_GPL(usb_acpi_power_manageable);
43
44 /**
45 * usb_acpi_set_power_state - control usb port's power via acpi power
46 * resource
47 * @hdev: USB device belonging to the usb hub
48 * @index: port index based zero
49 * @enable: power state expected to be set
50 *
51 * Notice to use usb_acpi_power_manageable() to check whether the usb port
52 * has acpi power resource before invoking this function.
53 *
54 * Returns 0 on success, else negative errno.
55 */
usb_acpi_set_power_state(struct usb_device * hdev,int index,bool enable)56 int usb_acpi_set_power_state(struct usb_device *hdev, int index, bool enable)
57 {
58 struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
59 struct usb_port *port_dev;
60 acpi_handle port_handle;
61 unsigned char state;
62 int port1 = index + 1;
63 int error = -EINVAL;
64
65 if (!hub)
66 return -ENODEV;
67 port_dev = hub->ports[port1 - 1];
68
69 port_handle = (acpi_handle) usb_get_hub_port_acpi_handle(hdev, port1);
70 if (!port_handle)
71 return error;
72
73 if (enable)
74 state = ACPI_STATE_D0;
75 else
76 state = ACPI_STATE_D3_COLD;
77
78 error = acpi_bus_set_power(port_handle, state);
79 if (!error)
80 dev_dbg(&port_dev->dev, "acpi: power was set to %d\n", enable);
81 else
82 dev_dbg(&port_dev->dev, "acpi: power failed to be set\n");
83
84 return error;
85 }
86 EXPORT_SYMBOL_GPL(usb_acpi_set_power_state);
87
usb_acpi_get_connect_type(acpi_handle handle,struct acpi_pld_info * pld)88 static enum usb_port_connect_type usb_acpi_get_connect_type(acpi_handle handle,
89 struct acpi_pld_info *pld)
90 {
91 enum usb_port_connect_type connect_type = USB_PORT_CONNECT_TYPE_UNKNOWN;
92 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
93 union acpi_object *upc;
94 acpi_status status;
95
96 /*
97 * According to ACPI Spec 9.13. PLD indicates whether usb port is
98 * user visible and _UPC indicates whether it is connectable. If
99 * the port was visible and connectable, it could be freely connected
100 * and disconnected with USB devices. If no visible and connectable,
101 * a usb device is directly hard-wired to the port. If no visible and
102 * no connectable, the port would be not used.
103 */
104 status = acpi_evaluate_object(handle, "_UPC", NULL, &buffer);
105 upc = buffer.pointer;
106 if (!upc || (upc->type != ACPI_TYPE_PACKAGE)
107 || upc->package.count != 4) {
108 goto out;
109 }
110
111 if (upc->package.elements[0].integer.value)
112 if (pld->user_visible)
113 connect_type = USB_PORT_CONNECT_TYPE_HOT_PLUG;
114 else
115 connect_type = USB_PORT_CONNECT_TYPE_HARD_WIRED;
116 else if (!pld->user_visible)
117 connect_type = USB_PORT_NOT_USED;
118 out:
119 kfree(upc);
120 return connect_type;
121 }
122
123
124 /*
125 * Private to usb-acpi, all the core needs to know is that
126 * port_dev->location is non-zero when it has been set by the firmware.
127 */
128 #define USB_ACPI_LOCATION_VALID (1 << 31)
129
usb_acpi_find_port(struct acpi_device * parent,int raw)130 static struct acpi_device *usb_acpi_find_port(struct acpi_device *parent,
131 int raw)
132 {
133 struct acpi_device *adev;
134
135 if (!parent)
136 return NULL;
137
138 list_for_each_entry(adev, &parent->children, node) {
139 if (acpi_device_adr(adev) == raw)
140 return adev;
141 }
142
143 return acpi_find_child_device(parent, raw, false);
144 }
145
usb_acpi_find_companion(struct device * dev)146 static struct acpi_device *usb_acpi_find_companion(struct device *dev)
147 {
148 struct usb_device *udev;
149 struct acpi_device *adev;
150 acpi_handle *parent_handle;
151
152 /*
153 * In the ACPI DSDT table, only usb root hub and usb ports are
154 * acpi device nodes. The hierarchy like following.
155 * Device (EHC1)
156 * Device (HUBN)
157 * Device (PR01)
158 * Device (PR11)
159 * Device (PR12)
160 * Device (PR13)
161 * ...
162 * So all binding process is divided into two parts. binding
163 * root hub and usb ports.
164 */
165 if (is_usb_device(dev)) {
166 udev = to_usb_device(dev);
167 if (udev->parent)
168 return NULL;
169
170 /* root hub is only child (_ADR=0) under its parent, the HC */
171 adev = ACPI_COMPANION(dev->parent);
172 return acpi_find_child_device(adev, 0, false);
173 } else if (is_usb_port(dev)) {
174 struct usb_port *port_dev = to_usb_port(dev);
175 int port1 = port_dev->portnum;
176 struct acpi_pld_info *pld;
177 acpi_handle *handle;
178 acpi_status status;
179
180 /* Get the struct usb_device point of port's hub */
181 udev = to_usb_device(dev->parent->parent);
182
183 /*
184 * The root hub ports' parent is the root hub. The non-root-hub
185 * ports' parent is the parent hub port which the hub is
186 * connected to.
187 */
188 if (!udev->parent) {
189 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
190 int raw;
191
192 raw = usb_hcd_find_raw_port_number(hcd, port1);
193
194 adev = usb_acpi_find_port(ACPI_COMPANION(&udev->dev),
195 raw);
196
197 if (!adev)
198 return NULL;
199 } else {
200 parent_handle =
201 usb_get_hub_port_acpi_handle(udev->parent,
202 udev->portnum);
203 if (!parent_handle)
204 return NULL;
205
206 acpi_bus_get_device(parent_handle, &adev);
207
208 adev = usb_acpi_find_port(adev, port1);
209
210 if (!adev)
211 return NULL;
212 }
213 handle = adev->handle;
214 status = acpi_get_physical_device_location(handle, &pld);
215 if (ACPI_FAILURE(status) || !pld)
216 return adev;
217
218 port_dev->location = USB_ACPI_LOCATION_VALID
219 | pld->group_token << 8 | pld->group_position;
220 port_dev->connect_type = usb_acpi_get_connect_type(handle, pld);
221 ACPI_FREE(pld);
222
223 return adev;
224 }
225
226 return NULL;
227 }
228
usb_acpi_bus_match(struct device * dev)229 static bool usb_acpi_bus_match(struct device *dev)
230 {
231 return is_usb_device(dev) || is_usb_port(dev);
232 }
233
234 static struct acpi_bus_type usb_acpi_bus = {
235 .name = "USB",
236 .match = usb_acpi_bus_match,
237 .find_companion = usb_acpi_find_companion,
238 };
239
usb_acpi_register(void)240 int usb_acpi_register(void)
241 {
242 return register_acpi_bus_type(&usb_acpi_bus);
243 }
244
usb_acpi_unregister(void)245 void usb_acpi_unregister(void)
246 {
247 unregister_acpi_bus_type(&usb_acpi_bus);
248 }
249