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22#include <linux/usb.h>
23#include <linux/usb/hcd.h>
24#include "usb.h"
25
26static inline const char *plural(int n)
27{
28 return (n == 1 ? "" : "s");
29}
30
31static int is_rndis(struct usb_interface_descriptor *desc)
32{
33 return desc->bInterfaceClass == USB_CLASS_COMM
34 && desc->bInterfaceSubClass == 2
35 && desc->bInterfaceProtocol == 0xff;
36}
37
38static int is_activesync(struct usb_interface_descriptor *desc)
39{
40 return desc->bInterfaceClass == USB_CLASS_MISC
41 && desc->bInterfaceSubClass == 1
42 && desc->bInterfaceProtocol == 1;
43}
44
45int usb_choose_configuration(struct usb_device *udev)
46{
47 int i;
48 int num_configs;
49 int insufficient_power = 0;
50 struct usb_host_config *c, *best;
51
52 if (usb_device_is_owned(udev))
53 return 0;
54
55 best = NULL;
56 c = udev->config;
57 num_configs = udev->descriptor.bNumConfigurations;
58 for (i = 0; i < num_configs; (i++, c++)) {
59 struct usb_interface_descriptor *desc = NULL;
60
61
62 if (c->desc.bNumInterfaces > 0)
63 desc = &c->intf_cache[0]->altsetting->desc;
64
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83
84
85#if 0
86
87 if (bus_powered && (c->desc.bmAttributes &
88 USB_CONFIG_ATT_SELFPOWER))
89 continue;
90#endif
91
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103
104
105 if (usb_get_max_power(udev, c) > udev->bus_mA) {
106 insufficient_power++;
107 continue;
108 }
109
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113
114
115 if (i == 0 && num_configs > 1 && desc &&
116 (is_rndis(desc) || is_activesync(desc))) {
117#if !defined(CONFIG_USB_NET_RNDIS_HOST) && !defined(CONFIG_USB_NET_RNDIS_HOST_MODULE)
118 continue;
119#else
120 best = c;
121#endif
122 }
123
124
125
126
127
128 else if (udev->descriptor.bDeviceClass !=
129 USB_CLASS_VENDOR_SPEC &&
130 (desc && desc->bInterfaceClass !=
131 USB_CLASS_VENDOR_SPEC)) {
132 best = c;
133 break;
134 }
135
136
137
138 else if (!best)
139 best = c;
140 }
141
142 if (insufficient_power > 0)
143 dev_info(&udev->dev, "rejected %d configuration%s "
144 "due to insufficient available bus power\n",
145 insufficient_power, plural(insufficient_power));
146
147 if (best) {
148 i = best->desc.bConfigurationValue;
149 dev_dbg(&udev->dev,
150 "configuration #%d chosen from %d choice%s\n",
151 i, num_configs, plural(num_configs));
152 } else {
153 i = -1;
154 dev_warn(&udev->dev,
155 "no configuration chosen from %d choice%s\n",
156 num_configs, plural(num_configs));
157 }
158 return i;
159}
160EXPORT_SYMBOL_GPL(usb_choose_configuration);
161
162static int generic_probe(struct usb_device *udev)
163{
164 int err, c;
165
166
167
168
169 if (udev->authorized == 0)
170 dev_err(&udev->dev, "Device is not authorized for usage\n");
171 else {
172 c = usb_choose_configuration(udev);
173 if (c >= 0) {
174 err = usb_set_configuration(udev, c);
175 if (err && err != -ENODEV) {
176 dev_err(&udev->dev, "can't set config #%d, error %d\n",
177 c, err);
178
179
180 }
181 }
182 }
183
184 usb_notify_add_device(udev);
185
186 return 0;
187}
188
189static void generic_disconnect(struct usb_device *udev)
190{
191 usb_notify_remove_device(udev);
192
193
194
195 if (udev->actconfig)
196 usb_set_configuration(udev, -1);
197}
198
199#ifdef CONFIG_PM
200
201static int generic_suspend(struct usb_device *udev, pm_message_t msg)
202{
203 int rc;
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210 if (!udev->parent)
211 rc = hcd_bus_suspend(udev, msg);
212
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217
218 else if ((msg.event == PM_EVENT_FREEZE || msg.event == PM_EVENT_PRETHAW)
219 && (udev->speed < USB_SPEED_SUPER))
220 rc = 0;
221 else
222 rc = usb_port_suspend(udev, msg);
223
224 return rc;
225}
226
227static int generic_resume(struct usb_device *udev, pm_message_t msg)
228{
229 int rc;
230
231
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234
235
236 if (!udev->parent)
237 rc = hcd_bus_resume(udev, msg);
238 else
239 rc = usb_port_resume(udev, msg);
240 return rc;
241}
242
243#endif
244
245struct usb_device_driver usb_generic_driver = {
246 .name = "usb",
247 .probe = generic_probe,
248 .disconnect = generic_disconnect,
249#ifdef CONFIG_PM
250 .suspend = generic_suspend,
251 .resume = generic_resume,
252#endif
253 .supports_autosuspend = 1,
254};
255