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20#include <linux/usb.h>
21#include <linux/usb/hcd.h>
22#include "usb.h"
23
24static inline const char *plural(int n)
25{
26 return (n == 1 ? "" : "s");
27}
28
29static int is_rndis(struct usb_interface_descriptor *desc)
30{
31 return desc->bInterfaceClass == USB_CLASS_COMM
32 && desc->bInterfaceSubClass == 2
33 && desc->bInterfaceProtocol == 0xff;
34}
35
36static int is_activesync(struct usb_interface_descriptor *desc)
37{
38 return desc->bInterfaceClass == USB_CLASS_MISC
39 && desc->bInterfaceSubClass == 1
40 && desc->bInterfaceProtocol == 1;
41}
42
43int usb_choose_configuration(struct usb_device *udev)
44{
45 int i;
46 int num_configs;
47 int insufficient_power = 0;
48 struct usb_host_config *c, *best;
49
50 if (usb_device_is_owned(udev))
51 return 0;
52
53 best = NULL;
54 c = udev->config;
55 num_configs = udev->descriptor.bNumConfigurations;
56 for (i = 0; i < num_configs; (i++, c++)) {
57 struct usb_interface_descriptor *desc = NULL;
58
59
60 if (c->desc.bNumInterfaces > 0)
61 desc = &c->intf_cache[0]->altsetting->desc;
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81
82
83#if 0
84
85 if (bus_powered && (c->desc.bmAttributes &
86 USB_CONFIG_ATT_SELFPOWER))
87 continue;
88#endif
89
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101
102
103 if (usb_get_max_power(udev, c) > udev->bus_mA) {
104 insufficient_power++;
105 continue;
106 }
107
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111
112
113 if (i == 0 && num_configs > 1 && desc &&
114 (is_rndis(desc) || is_activesync(desc))) {
115#if !defined(CONFIG_USB_NET_RNDIS_HOST) && !defined(CONFIG_USB_NET_RNDIS_HOST_MODULE)
116 continue;
117#else
118 best = c;
119#endif
120 }
121
122
123
124
125
126 else if (udev->descriptor.bDeviceClass !=
127 USB_CLASS_VENDOR_SPEC &&
128 (desc && desc->bInterfaceClass !=
129 USB_CLASS_VENDOR_SPEC)) {
130 best = c;
131 break;
132 }
133
134
135
136 else if (!best)
137 best = c;
138 }
139
140 if (insufficient_power > 0)
141 dev_info(&udev->dev, "rejected %d configuration%s "
142 "due to insufficient available bus power\n",
143 insufficient_power, plural(insufficient_power));
144
145 if (best) {
146 i = best->desc.bConfigurationValue;
147 dev_dbg(&udev->dev,
148 "configuration #%d chosen from %d choice%s\n",
149 i, num_configs, plural(num_configs));
150 } else {
151 i = -1;
152 dev_warn(&udev->dev,
153 "no configuration chosen from %d choice%s\n",
154 num_configs, plural(num_configs));
155 }
156 return i;
157}
158EXPORT_SYMBOL_GPL(usb_choose_configuration);
159
160static int generic_probe(struct usb_device *udev)
161{
162 int err, c;
163
164
165
166
167 if (udev->authorized == 0)
168 dev_err(&udev->dev, "Device is not authorized for usage\n");
169 else {
170 c = usb_choose_configuration(udev);
171 if (c >= 0) {
172 err = usb_set_configuration(udev, c);
173 if (err && err != -ENODEV) {
174 dev_err(&udev->dev, "can't set config #%d, error %d\n",
175 c, err);
176
177
178 }
179 }
180 }
181
182 usb_notify_add_device(udev);
183
184 return 0;
185}
186
187static void generic_disconnect(struct usb_device *udev)
188{
189 usb_notify_remove_device(udev);
190
191
192
193 if (udev->actconfig)
194 usb_set_configuration(udev, -1);
195}
196
197#ifdef CONFIG_PM
198
199static int generic_suspend(struct usb_device *udev, pm_message_t msg)
200{
201 int rc;
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208 if (!udev->parent)
209 rc = hcd_bus_suspend(udev, msg);
210
211
212 else if (msg.event == PM_EVENT_FREEZE || msg.event == PM_EVENT_PRETHAW)
213 rc = 0;
214 else
215 rc = usb_port_suspend(udev, msg);
216
217 return rc;
218}
219
220static int generic_resume(struct usb_device *udev, pm_message_t msg)
221{
222 int rc;
223
224
225
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227
228
229 if (!udev->parent)
230 rc = hcd_bus_resume(udev, msg);
231 else
232 rc = usb_port_resume(udev, msg);
233 return rc;
234}
235
236#endif
237
238struct usb_device_driver usb_generic_driver = {
239 .name = "usb",
240 .probe = generic_probe,
241 .disconnect = generic_disconnect,
242#ifdef CONFIG_PM
243 .suspend = generic_suspend,
244 .resume = generic_resume,
245#endif
246 .supports_autosuspend = 1,
247};
248