Merge commit 'v2.6.28-rc6' into x86/debug
[linux-2.6] / drivers / usb / core / hub.c
1 /*
2  * USB hub driver.
3  *
4  * (C) Copyright 1999 Linus Torvalds
5  * (C) Copyright 1999 Johannes Erdfelt
6  * (C) Copyright 1999 Gregory P. Smith
7  * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
8  *
9  */
10
11 #include <linux/kernel.h>
12 #include <linux/errno.h>
13 #include <linux/module.h>
14 #include <linux/moduleparam.h>
15 #include <linux/completion.h>
16 #include <linux/sched.h>
17 #include <linux/list.h>
18 #include <linux/slab.h>
19 #include <linux/ioctl.h>
20 #include <linux/usb.h>
21 #include <linux/usbdevice_fs.h>
22 #include <linux/kthread.h>
23 #include <linux/mutex.h>
24 #include <linux/freezer.h>
25
26 #include <asm/uaccess.h>
27 #include <asm/byteorder.h>
28
29 #include "usb.h"
30 #include "hcd.h"
31 #include "hub.h"
32
33 /* if we are in debug mode, always announce new devices */
34 #ifdef DEBUG
35 #ifndef CONFIG_USB_ANNOUNCE_NEW_DEVICES
36 #define CONFIG_USB_ANNOUNCE_NEW_DEVICES
37 #endif
38 #endif
39
40 struct usb_hub {
41         struct device           *intfdev;       /* the "interface" device */
42         struct usb_device       *hdev;
43         struct kref             kref;
44         struct urb              *urb;           /* for interrupt polling pipe */
45
46         /* buffer for urb ... with extra space in case of babble */
47         char                    (*buffer)[8];
48         dma_addr_t              buffer_dma;     /* DMA address for buffer */
49         union {
50                 struct usb_hub_status   hub;
51                 struct usb_port_status  port;
52         }                       *status;        /* buffer for status reports */
53         struct mutex            status_mutex;   /* for the status buffer */
54
55         int                     error;          /* last reported error */
56         int                     nerrors;        /* track consecutive errors */
57
58         struct list_head        event_list;     /* hubs w/data or errs ready */
59         unsigned long           event_bits[1];  /* status change bitmask */
60         unsigned long           change_bits[1]; /* ports with logical connect
61                                                         status change */
62         unsigned long           busy_bits[1];   /* ports being reset or
63                                                         resumed */
64 #if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
65 #error event_bits[] is too short!
66 #endif
67
68         struct usb_hub_descriptor *descriptor;  /* class descriptor */
69         struct usb_tt           tt;             /* Transaction Translator */
70
71         unsigned                mA_per_port;    /* current for each child */
72
73         unsigned                limited_power:1;
74         unsigned                quiescing:1;
75         unsigned                disconnected:1;
76
77         unsigned                has_indicators:1;
78         u8                      indicator[USB_MAXCHILDREN];
79         struct delayed_work     leds;
80         struct delayed_work     init_work;
81 };
82
83
84 /* Protect struct usb_device->state and ->children members
85  * Note: Both are also protected by ->dev.sem, except that ->state can
86  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
87 static DEFINE_SPINLOCK(device_state_lock);
88
89 /* khubd's worklist and its lock */
90 static DEFINE_SPINLOCK(hub_event_lock);
91 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
92
93 /* Wakes up khubd */
94 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
95
96 static struct task_struct *khubd_task;
97
98 /* cycle leds on hubs that aren't blinking for attention */
99 static int blinkenlights = 0;
100 module_param (blinkenlights, bool, S_IRUGO);
101 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
102
103 /*
104  * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
105  * 10 seconds to send reply for the initial 64-byte descriptor request.
106  */
107 /* define initial 64-byte descriptor request timeout in milliseconds */
108 static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
109 module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
110 MODULE_PARM_DESC(initial_descriptor_timeout, "initial 64-byte descriptor request timeout in milliseconds (default 5000 - 5.0 seconds)");
111
112 /*
113  * As of 2.6.10 we introduce a new USB device initialization scheme which
114  * closely resembles the way Windows works.  Hopefully it will be compatible
115  * with a wider range of devices than the old scheme.  However some previously
116  * working devices may start giving rise to "device not accepting address"
117  * errors; if that happens the user can try the old scheme by adjusting the
118  * following module parameters.
119  *
120  * For maximum flexibility there are two boolean parameters to control the
121  * hub driver's behavior.  On the first initialization attempt, if the
122  * "old_scheme_first" parameter is set then the old scheme will be used,
123  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
124  * is set, then the driver will make another attempt, using the other scheme.
125  */
126 static int old_scheme_first = 0;
127 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
128 MODULE_PARM_DESC(old_scheme_first,
129                  "start with the old device initialization scheme");
130
131 static int use_both_schemes = 1;
132 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
133 MODULE_PARM_DESC(use_both_schemes,
134                 "try the other device initialization scheme if the "
135                 "first one fails");
136
137 /* Mutual exclusion for EHCI CF initialization.  This interferes with
138  * port reset on some companion controllers.
139  */
140 DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
141 EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
142
143 #define HUB_DEBOUNCE_TIMEOUT    1500
144 #define HUB_DEBOUNCE_STEP         25
145 #define HUB_DEBOUNCE_STABLE      100
146
147
148 static int usb_reset_and_verify_device(struct usb_device *udev);
149
150 static inline char *portspeed(int portstatus)
151 {
152         if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
153                 return "480 Mb/s";
154         else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
155                 return "1.5 Mb/s";
156         else
157                 return "12 Mb/s";
158 }
159
160 /* Note that hdev or one of its children must be locked! */
161 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
162 {
163         return usb_get_intfdata(hdev->actconfig->interface[0]);
164 }
165
166 /* USB 2.0 spec Section 11.24.4.5 */
167 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
168 {
169         int i, ret;
170
171         for (i = 0; i < 3; i++) {
172                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
173                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
174                         USB_DT_HUB << 8, 0, data, size,
175                         USB_CTRL_GET_TIMEOUT);
176                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
177                         return ret;
178         }
179         return -EINVAL;
180 }
181
182 /*
183  * USB 2.0 spec Section 11.24.2.1
184  */
185 static int clear_hub_feature(struct usb_device *hdev, int feature)
186 {
187         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
188                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
189 }
190
191 /*
192  * USB 2.0 spec Section 11.24.2.2
193  */
194 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
195 {
196         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
197                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
198                 NULL, 0, 1000);
199 }
200
201 /*
202  * USB 2.0 spec Section 11.24.2.13
203  */
204 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
205 {
206         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
207                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
208                 NULL, 0, 1000);
209 }
210
211 /*
212  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
213  * for info about using port indicators
214  */
215 static void set_port_led(
216         struct usb_hub *hub,
217         int port1,
218         int selector
219 )
220 {
221         int status = set_port_feature(hub->hdev, (selector << 8) | port1,
222                         USB_PORT_FEAT_INDICATOR);
223         if (status < 0)
224                 dev_dbg (hub->intfdev,
225                         "port %d indicator %s status %d\n",
226                         port1,
227                         ({ char *s; switch (selector) {
228                         case HUB_LED_AMBER: s = "amber"; break;
229                         case HUB_LED_GREEN: s = "green"; break;
230                         case HUB_LED_OFF: s = "off"; break;
231                         case HUB_LED_AUTO: s = "auto"; break;
232                         default: s = "??"; break;
233                         }; s; }),
234                         status);
235 }
236
237 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
238
239 static void led_work (struct work_struct *work)
240 {
241         struct usb_hub          *hub =
242                 container_of(work, struct usb_hub, leds.work);
243         struct usb_device       *hdev = hub->hdev;
244         unsigned                i;
245         unsigned                changed = 0;
246         int                     cursor = -1;
247
248         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
249                 return;
250
251         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
252                 unsigned        selector, mode;
253
254                 /* 30%-50% duty cycle */
255
256                 switch (hub->indicator[i]) {
257                 /* cycle marker */
258                 case INDICATOR_CYCLE:
259                         cursor = i;
260                         selector = HUB_LED_AUTO;
261                         mode = INDICATOR_AUTO;
262                         break;
263                 /* blinking green = sw attention */
264                 case INDICATOR_GREEN_BLINK:
265                         selector = HUB_LED_GREEN;
266                         mode = INDICATOR_GREEN_BLINK_OFF;
267                         break;
268                 case INDICATOR_GREEN_BLINK_OFF:
269                         selector = HUB_LED_OFF;
270                         mode = INDICATOR_GREEN_BLINK;
271                         break;
272                 /* blinking amber = hw attention */
273                 case INDICATOR_AMBER_BLINK:
274                         selector = HUB_LED_AMBER;
275                         mode = INDICATOR_AMBER_BLINK_OFF;
276                         break;
277                 case INDICATOR_AMBER_BLINK_OFF:
278                         selector = HUB_LED_OFF;
279                         mode = INDICATOR_AMBER_BLINK;
280                         break;
281                 /* blink green/amber = reserved */
282                 case INDICATOR_ALT_BLINK:
283                         selector = HUB_LED_GREEN;
284                         mode = INDICATOR_ALT_BLINK_OFF;
285                         break;
286                 case INDICATOR_ALT_BLINK_OFF:
287                         selector = HUB_LED_AMBER;
288                         mode = INDICATOR_ALT_BLINK;
289                         break;
290                 default:
291                         continue;
292                 }
293                 if (selector != HUB_LED_AUTO)
294                         changed = 1;
295                 set_port_led(hub, i + 1, selector);
296                 hub->indicator[i] = mode;
297         }
298         if (!changed && blinkenlights) {
299                 cursor++;
300                 cursor %= hub->descriptor->bNbrPorts;
301                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
302                 hub->indicator[cursor] = INDICATOR_CYCLE;
303                 changed++;
304         }
305         if (changed)
306                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
307 }
308
309 /* use a short timeout for hub/port status fetches */
310 #define USB_STS_TIMEOUT         1000
311 #define USB_STS_RETRIES         5
312
313 /*
314  * USB 2.0 spec Section 11.24.2.6
315  */
316 static int get_hub_status(struct usb_device *hdev,
317                 struct usb_hub_status *data)
318 {
319         int i, status = -ETIMEDOUT;
320
321         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
322                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
323                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
324                         data, sizeof(*data), USB_STS_TIMEOUT);
325         }
326         return status;
327 }
328
329 /*
330  * USB 2.0 spec Section 11.24.2.7
331  */
332 static int get_port_status(struct usb_device *hdev, int port1,
333                 struct usb_port_status *data)
334 {
335         int i, status = -ETIMEDOUT;
336
337         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
338                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
339                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
340                         data, sizeof(*data), USB_STS_TIMEOUT);
341         }
342         return status;
343 }
344
345 static int hub_port_status(struct usb_hub *hub, int port1,
346                 u16 *status, u16 *change)
347 {
348         int ret;
349
350         mutex_lock(&hub->status_mutex);
351         ret = get_port_status(hub->hdev, port1, &hub->status->port);
352         if (ret < 4) {
353                 dev_err(hub->intfdev,
354                         "%s failed (err = %d)\n", __func__, ret);
355                 if (ret >= 0)
356                         ret = -EIO;
357         } else {
358                 *status = le16_to_cpu(hub->status->port.wPortStatus);
359                 *change = le16_to_cpu(hub->status->port.wPortChange);
360                 ret = 0;
361         }
362         mutex_unlock(&hub->status_mutex);
363         return ret;
364 }
365
366 static void kick_khubd(struct usb_hub *hub)
367 {
368         unsigned long   flags;
369
370         /* Suppress autosuspend until khubd runs */
371         to_usb_interface(hub->intfdev)->pm_usage_cnt = 1;
372
373         spin_lock_irqsave(&hub_event_lock, flags);
374         if (!hub->disconnected && list_empty(&hub->event_list)) {
375                 list_add_tail(&hub->event_list, &hub_event_list);
376                 wake_up(&khubd_wait);
377         }
378         spin_unlock_irqrestore(&hub_event_lock, flags);
379 }
380
381 void usb_kick_khubd(struct usb_device *hdev)
382 {
383         /* FIXME: What if hdev isn't bound to the hub driver? */
384         kick_khubd(hdev_to_hub(hdev));
385 }
386
387
388 /* completion function, fires on port status changes and various faults */
389 static void hub_irq(struct urb *urb)
390 {
391         struct usb_hub *hub = urb->context;
392         int status = urb->status;
393         int i;
394         unsigned long bits;
395
396         switch (status) {
397         case -ENOENT:           /* synchronous unlink */
398         case -ECONNRESET:       /* async unlink */
399         case -ESHUTDOWN:        /* hardware going away */
400                 return;
401
402         default:                /* presumably an error */
403                 /* Cause a hub reset after 10 consecutive errors */
404                 dev_dbg (hub->intfdev, "transfer --> %d\n", status);
405                 if ((++hub->nerrors < 10) || hub->error)
406                         goto resubmit;
407                 hub->error = status;
408                 /* FALL THROUGH */
409
410         /* let khubd handle things */
411         case 0:                 /* we got data:  port status changed */
412                 bits = 0;
413                 for (i = 0; i < urb->actual_length; ++i)
414                         bits |= ((unsigned long) ((*hub->buffer)[i]))
415                                         << (i*8);
416                 hub->event_bits[0] = bits;
417                 break;
418         }
419
420         hub->nerrors = 0;
421
422         /* Something happened, let khubd figure it out */
423         kick_khubd(hub);
424
425 resubmit:
426         if (hub->quiescing)
427                 return;
428
429         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
430                         && status != -ENODEV && status != -EPERM)
431                 dev_err (hub->intfdev, "resubmit --> %d\n", status);
432 }
433
434 /* USB 2.0 spec Section 11.24.2.3 */
435 static inline int
436 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
437 {
438         return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
439                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
440                                tt, NULL, 0, 1000);
441 }
442
443 /*
444  * enumeration blocks khubd for a long time. we use keventd instead, since
445  * long blocking there is the exception, not the rule.  accordingly, HCDs
446  * talking to TTs must queue control transfers (not just bulk and iso), so
447  * both can talk to the same hub concurrently.
448  */
449 static void hub_tt_kevent (struct work_struct *work)
450 {
451         struct usb_hub          *hub =
452                 container_of(work, struct usb_hub, tt.kevent);
453         unsigned long           flags;
454         int                     limit = 100;
455
456         spin_lock_irqsave (&hub->tt.lock, flags);
457         while (--limit && !list_empty (&hub->tt.clear_list)) {
458                 struct list_head        *temp;
459                 struct usb_tt_clear     *clear;
460                 struct usb_device       *hdev = hub->hdev;
461                 int                     status;
462
463                 temp = hub->tt.clear_list.next;
464                 clear = list_entry (temp, struct usb_tt_clear, clear_list);
465                 list_del (&clear->clear_list);
466
467                 /* drop lock so HCD can concurrently report other TT errors */
468                 spin_unlock_irqrestore (&hub->tt.lock, flags);
469                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
470                 spin_lock_irqsave (&hub->tt.lock, flags);
471
472                 if (status)
473                         dev_err (&hdev->dev,
474                                 "clear tt %d (%04x) error %d\n",
475                                 clear->tt, clear->devinfo, status);
476                 kfree(clear);
477         }
478         spin_unlock_irqrestore (&hub->tt.lock, flags);
479 }
480
481 /**
482  * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
483  * @udev: the device whose split transaction failed
484  * @pipe: identifies the endpoint of the failed transaction
485  *
486  * High speed HCDs use this to tell the hub driver that some split control or
487  * bulk transaction failed in a way that requires clearing internal state of
488  * a transaction translator.  This is normally detected (and reported) from
489  * interrupt context.
490  *
491  * It may not be possible for that hub to handle additional full (or low)
492  * speed transactions until that state is fully cleared out.
493  */
494 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
495 {
496         struct usb_tt           *tt = udev->tt;
497         unsigned long           flags;
498         struct usb_tt_clear     *clear;
499
500         /* we've got to cope with an arbitrary number of pending TT clears,
501          * since each TT has "at least two" buffers that can need it (and
502          * there can be many TTs per hub).  even if they're uncommon.
503          */
504         if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
505                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
506                 /* FIXME recover somehow ... RESET_TT? */
507                 return;
508         }
509
510         /* info that CLEAR_TT_BUFFER needs */
511         clear->tt = tt->multi ? udev->ttport : 1;
512         clear->devinfo = usb_pipeendpoint (pipe);
513         clear->devinfo |= udev->devnum << 4;
514         clear->devinfo |= usb_pipecontrol (pipe)
515                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
516                         : (USB_ENDPOINT_XFER_BULK << 11);
517         if (usb_pipein (pipe))
518                 clear->devinfo |= 1 << 15;
519         
520         /* tell keventd to clear state for this TT */
521         spin_lock_irqsave (&tt->lock, flags);
522         list_add_tail (&clear->clear_list, &tt->clear_list);
523         schedule_work (&tt->kevent);
524         spin_unlock_irqrestore (&tt->lock, flags);
525 }
526 EXPORT_SYMBOL_GPL(usb_hub_tt_clear_buffer);
527
528 /* If do_delay is false, return the number of milliseconds the caller
529  * needs to delay.
530  */
531 static unsigned hub_power_on(struct usb_hub *hub, bool do_delay)
532 {
533         int port1;
534         unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
535         unsigned delay;
536         u16 wHubCharacteristics =
537                         le16_to_cpu(hub->descriptor->wHubCharacteristics);
538
539         /* Enable power on each port.  Some hubs have reserved values
540          * of LPSM (> 2) in their descriptors, even though they are
541          * USB 2.0 hubs.  Some hubs do not implement port-power switching
542          * but only emulate it.  In all cases, the ports won't work
543          * unless we send these messages to the hub.
544          */
545         if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
546                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
547         else
548                 dev_dbg(hub->intfdev, "trying to enable port power on "
549                                 "non-switchable hub\n");
550         for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
551                 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
552
553         /* Wait at least 100 msec for power to become stable */
554         delay = max(pgood_delay, (unsigned) 100);
555         if (do_delay)
556                 msleep(delay);
557         return delay;
558 }
559
560 static int hub_hub_status(struct usb_hub *hub,
561                 u16 *status, u16 *change)
562 {
563         int ret;
564
565         mutex_lock(&hub->status_mutex);
566         ret = get_hub_status(hub->hdev, &hub->status->hub);
567         if (ret < 0)
568                 dev_err (hub->intfdev,
569                         "%s failed (err = %d)\n", __func__, ret);
570         else {
571                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
572                 *change = le16_to_cpu(hub->status->hub.wHubChange); 
573                 ret = 0;
574         }
575         mutex_unlock(&hub->status_mutex);
576         return ret;
577 }
578
579 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
580 {
581         struct usb_device *hdev = hub->hdev;
582         int ret = 0;
583
584         if (hdev->children[port1-1] && set_state)
585                 usb_set_device_state(hdev->children[port1-1],
586                                 USB_STATE_NOTATTACHED);
587         if (!hub->error)
588                 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
589         if (ret)
590                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
591                                 port1, ret);
592         return ret;
593 }
594
595 /*
596  * Disable a port and mark a logical connnect-change event, so that some
597  * time later khubd will disconnect() any existing usb_device on the port
598  * and will re-enumerate if there actually is a device attached.
599  */
600 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
601 {
602         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
603         hub_port_disable(hub, port1, 1);
604
605         /* FIXME let caller ask to power down the port:
606          *  - some devices won't enumerate without a VBUS power cycle
607          *  - SRP saves power that way
608          *  - ... new call, TBD ...
609          * That's easy if this hub can switch power per-port, and
610          * khubd reactivates the port later (timer, SRP, etc).
611          * Powerdown must be optional, because of reset/DFU.
612          */
613
614         set_bit(port1, hub->change_bits);
615         kick_khubd(hub);
616 }
617
618 enum hub_activation_type {
619         HUB_INIT, HUB_INIT2, HUB_INIT3,
620         HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
621 };
622
623 static void hub_init_func2(struct work_struct *ws);
624 static void hub_init_func3(struct work_struct *ws);
625
626 static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
627 {
628         struct usb_device *hdev = hub->hdev;
629         int port1;
630         int status;
631         bool need_debounce_delay = false;
632         unsigned delay;
633
634         /* Continue a partial initialization */
635         if (type == HUB_INIT2)
636                 goto init2;
637         if (type == HUB_INIT3)
638                 goto init3;
639
640         /* After a resume, port power should still be on.
641          * For any other type of activation, turn it on.
642          */
643         if (type != HUB_RESUME) {
644
645                 /* Speed up system boot by using a delayed_work for the
646                  * hub's initial power-up delays.  This is pretty awkward
647                  * and the implementation looks like a home-brewed sort of
648                  * setjmp/longjmp, but it saves at least 100 ms for each
649                  * root hub (assuming usbcore is compiled into the kernel
650                  * rather than as a module).  It adds up.
651                  *
652                  * This can't be done for HUB_RESUME or HUB_RESET_RESUME
653                  * because for those activation types the ports have to be
654                  * operational when we return.  In theory this could be done
655                  * for HUB_POST_RESET, but it's easier not to.
656                  */
657                 if (type == HUB_INIT) {
658                         delay = hub_power_on(hub, false);
659                         PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func2);
660                         schedule_delayed_work(&hub->init_work,
661                                         msecs_to_jiffies(delay));
662
663                         /* Suppress autosuspend until init is done */
664                         to_usb_interface(hub->intfdev)->pm_usage_cnt = 1;
665                         return;         /* Continues at init2: below */
666                 } else {
667                         hub_power_on(hub, true);
668                 }
669         }
670  init2:
671
672         /* Check each port and set hub->change_bits to let khubd know
673          * which ports need attention.
674          */
675         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
676                 struct usb_device *udev = hdev->children[port1-1];
677                 u16 portstatus, portchange;
678
679                 portstatus = portchange = 0;
680                 status = hub_port_status(hub, port1, &portstatus, &portchange);
681                 if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
682                         dev_dbg(hub->intfdev,
683                                         "port %d: status %04x change %04x\n",
684                                         port1, portstatus, portchange);
685
686                 /* After anything other than HUB_RESUME (i.e., initialization
687                  * or any sort of reset), every port should be disabled.
688                  * Unconnected ports should likewise be disabled (paranoia),
689                  * and so should ports for which we have no usb_device.
690                  */
691                 if ((portstatus & USB_PORT_STAT_ENABLE) && (
692                                 type != HUB_RESUME ||
693                                 !(portstatus & USB_PORT_STAT_CONNECTION) ||
694                                 !udev ||
695                                 udev->state == USB_STATE_NOTATTACHED)) {
696                         clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
697                         portstatus &= ~USB_PORT_STAT_ENABLE;
698                 }
699
700                 /* Clear status-change flags; we'll debounce later */
701                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
702                         need_debounce_delay = true;
703                         clear_port_feature(hub->hdev, port1,
704                                         USB_PORT_FEAT_C_CONNECTION);
705                 }
706                 if (portchange & USB_PORT_STAT_C_ENABLE) {
707                         need_debounce_delay = true;
708                         clear_port_feature(hub->hdev, port1,
709                                         USB_PORT_FEAT_C_ENABLE);
710                 }
711
712                 if (!udev || udev->state == USB_STATE_NOTATTACHED) {
713                         /* Tell khubd to disconnect the device or
714                          * check for a new connection
715                          */
716                         if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
717                                 set_bit(port1, hub->change_bits);
718
719                 } else if (portstatus & USB_PORT_STAT_ENABLE) {
720                         /* The power session apparently survived the resume.
721                          * If there was an overcurrent or suspend change
722                          * (i.e., remote wakeup request), have khubd
723                          * take care of it.
724                          */
725                         if (portchange)
726                                 set_bit(port1, hub->change_bits);
727
728                 } else if (udev->persist_enabled) {
729 #ifdef CONFIG_PM
730                         udev->reset_resume = 1;
731 #endif
732                         set_bit(port1, hub->change_bits);
733
734                 } else {
735                         /* The power session is gone; tell khubd */
736                         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
737                         set_bit(port1, hub->change_bits);
738                 }
739         }
740
741         /* If no port-status-change flags were set, we don't need any
742          * debouncing.  If flags were set we can try to debounce the
743          * ports all at once right now, instead of letting khubd do them
744          * one at a time later on.
745          *
746          * If any port-status changes do occur during this delay, khubd
747          * will see them later and handle them normally.
748          */
749         if (need_debounce_delay) {
750                 delay = HUB_DEBOUNCE_STABLE;
751
752                 /* Don't do a long sleep inside a workqueue routine */
753                 if (type == HUB_INIT2) {
754                         PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func3);
755                         schedule_delayed_work(&hub->init_work,
756                                         msecs_to_jiffies(delay));
757                         return;         /* Continues at init3: below */
758                 } else {
759                         msleep(delay);
760                 }
761         }
762  init3:
763         hub->quiescing = 0;
764
765         status = usb_submit_urb(hub->urb, GFP_NOIO);
766         if (status < 0)
767                 dev_err(hub->intfdev, "activate --> %d\n", status);
768         if (hub->has_indicators && blinkenlights)
769                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
770
771         /* Scan all ports that need attention */
772         kick_khubd(hub);
773 }
774
775 /* Implement the continuations for the delays above */
776 static void hub_init_func2(struct work_struct *ws)
777 {
778         struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
779
780         hub_activate(hub, HUB_INIT2);
781 }
782
783 static void hub_init_func3(struct work_struct *ws)
784 {
785         struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
786
787         hub_activate(hub, HUB_INIT3);
788 }
789
790 enum hub_quiescing_type {
791         HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
792 };
793
794 static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
795 {
796         struct usb_device *hdev = hub->hdev;
797         int i;
798
799         cancel_delayed_work_sync(&hub->init_work);
800
801         /* khubd and related activity won't re-trigger */
802         hub->quiescing = 1;
803
804         if (type != HUB_SUSPEND) {
805                 /* Disconnect all the children */
806                 for (i = 0; i < hdev->maxchild; ++i) {
807                         if (hdev->children[i])
808                                 usb_disconnect(&hdev->children[i]);
809                 }
810         }
811
812         /* Stop khubd and related activity */
813         usb_kill_urb(hub->urb);
814         if (hub->has_indicators)
815                 cancel_delayed_work_sync(&hub->leds);
816         if (hub->tt.hub)
817                 cancel_work_sync(&hub->tt.kevent);
818 }
819
820 /* caller has locked the hub device */
821 static int hub_pre_reset(struct usb_interface *intf)
822 {
823         struct usb_hub *hub = usb_get_intfdata(intf);
824
825         hub_quiesce(hub, HUB_PRE_RESET);
826         return 0;
827 }
828
829 /* caller has locked the hub device */
830 static int hub_post_reset(struct usb_interface *intf)
831 {
832         struct usb_hub *hub = usb_get_intfdata(intf);
833
834         hub_activate(hub, HUB_POST_RESET);
835         return 0;
836 }
837
838 static int hub_configure(struct usb_hub *hub,
839         struct usb_endpoint_descriptor *endpoint)
840 {
841         struct usb_device *hdev = hub->hdev;
842         struct device *hub_dev = hub->intfdev;
843         u16 hubstatus, hubchange;
844         u16 wHubCharacteristics;
845         unsigned int pipe;
846         int maxp, ret;
847         char *message;
848
849         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
850                         &hub->buffer_dma);
851         if (!hub->buffer) {
852                 message = "can't allocate hub irq buffer";
853                 ret = -ENOMEM;
854                 goto fail;
855         }
856
857         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
858         if (!hub->status) {
859                 message = "can't kmalloc hub status buffer";
860                 ret = -ENOMEM;
861                 goto fail;
862         }
863         mutex_init(&hub->status_mutex);
864
865         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
866         if (!hub->descriptor) {
867                 message = "can't kmalloc hub descriptor";
868                 ret = -ENOMEM;
869                 goto fail;
870         }
871
872         /* Request the entire hub descriptor.
873          * hub->descriptor can handle USB_MAXCHILDREN ports,
874          * but the hub can/will return fewer bytes here.
875          */
876         ret = get_hub_descriptor(hdev, hub->descriptor,
877                         sizeof(*hub->descriptor));
878         if (ret < 0) {
879                 message = "can't read hub descriptor";
880                 goto fail;
881         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
882                 message = "hub has too many ports!";
883                 ret = -ENODEV;
884                 goto fail;
885         }
886
887         hdev->maxchild = hub->descriptor->bNbrPorts;
888         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
889                 (hdev->maxchild == 1) ? "" : "s");
890
891         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
892
893         if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
894                 int     i;
895                 char    portstr [USB_MAXCHILDREN + 1];
896
897                 for (i = 0; i < hdev->maxchild; i++)
898                         portstr[i] = hub->descriptor->DeviceRemovable
899                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
900                                 ? 'F' : 'R';
901                 portstr[hdev->maxchild] = 0;
902                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
903         } else
904                 dev_dbg(hub_dev, "standalone hub\n");
905
906         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
907                 case 0x00:
908                         dev_dbg(hub_dev, "ganged power switching\n");
909                         break;
910                 case 0x01:
911                         dev_dbg(hub_dev, "individual port power switching\n");
912                         break;
913                 case 0x02:
914                 case 0x03:
915                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
916                         break;
917         }
918
919         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
920                 case 0x00:
921                         dev_dbg(hub_dev, "global over-current protection\n");
922                         break;
923                 case 0x08:
924                         dev_dbg(hub_dev, "individual port over-current protection\n");
925                         break;
926                 case 0x10:
927                 case 0x18:
928                         dev_dbg(hub_dev, "no over-current protection\n");
929                         break;
930         }
931
932         spin_lock_init (&hub->tt.lock);
933         INIT_LIST_HEAD (&hub->tt.clear_list);
934         INIT_WORK (&hub->tt.kevent, hub_tt_kevent);
935         switch (hdev->descriptor.bDeviceProtocol) {
936                 case 0:
937                         break;
938                 case 1:
939                         dev_dbg(hub_dev, "Single TT\n");
940                         hub->tt.hub = hdev;
941                         break;
942                 case 2:
943                         ret = usb_set_interface(hdev, 0, 1);
944                         if (ret == 0) {
945                                 dev_dbg(hub_dev, "TT per port\n");
946                                 hub->tt.multi = 1;
947                         } else
948                                 dev_err(hub_dev, "Using single TT (err %d)\n",
949                                         ret);
950                         hub->tt.hub = hdev;
951                         break;
952                 default:
953                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
954                                 hdev->descriptor.bDeviceProtocol);
955                         break;
956         }
957
958         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
959         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
960                 case HUB_TTTT_8_BITS:
961                         if (hdev->descriptor.bDeviceProtocol != 0) {
962                                 hub->tt.think_time = 666;
963                                 dev_dbg(hub_dev, "TT requires at most %d "
964                                                 "FS bit times (%d ns)\n",
965                                         8, hub->tt.think_time);
966                         }
967                         break;
968                 case HUB_TTTT_16_BITS:
969                         hub->tt.think_time = 666 * 2;
970                         dev_dbg(hub_dev, "TT requires at most %d "
971                                         "FS bit times (%d ns)\n",
972                                 16, hub->tt.think_time);
973                         break;
974                 case HUB_TTTT_24_BITS:
975                         hub->tt.think_time = 666 * 3;
976                         dev_dbg(hub_dev, "TT requires at most %d "
977                                         "FS bit times (%d ns)\n",
978                                 24, hub->tt.think_time);
979                         break;
980                 case HUB_TTTT_32_BITS:
981                         hub->tt.think_time = 666 * 4;
982                         dev_dbg(hub_dev, "TT requires at most %d "
983                                         "FS bit times (%d ns)\n",
984                                 32, hub->tt.think_time);
985                         break;
986         }
987
988         /* probe() zeroes hub->indicator[] */
989         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
990                 hub->has_indicators = 1;
991                 dev_dbg(hub_dev, "Port indicators are supported\n");
992         }
993
994         dev_dbg(hub_dev, "power on to power good time: %dms\n",
995                 hub->descriptor->bPwrOn2PwrGood * 2);
996
997         /* power budgeting mostly matters with bus-powered hubs,
998          * and battery-powered root hubs (may provide just 8 mA).
999          */
1000         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1001         if (ret < 2) {
1002                 message = "can't get hub status";
1003                 goto fail;
1004         }
1005         le16_to_cpus(&hubstatus);
1006         if (hdev == hdev->bus->root_hub) {
1007                 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
1008                         hub->mA_per_port = 500;
1009                 else {
1010                         hub->mA_per_port = hdev->bus_mA;
1011                         hub->limited_power = 1;
1012                 }
1013         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1014                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1015                         hub->descriptor->bHubContrCurrent);
1016                 hub->limited_power = 1;
1017                 if (hdev->maxchild > 0) {
1018                         int remaining = hdev->bus_mA -
1019                                         hub->descriptor->bHubContrCurrent;
1020
1021                         if (remaining < hdev->maxchild * 100)
1022                                 dev_warn(hub_dev,
1023                                         "insufficient power available "
1024                                         "to use all downstream ports\n");
1025                         hub->mA_per_port = 100;         /* 7.2.1.1 */
1026                 }
1027         } else {        /* Self-powered external hub */
1028                 /* FIXME: What about battery-powered external hubs that
1029                  * provide less current per port? */
1030                 hub->mA_per_port = 500;
1031         }
1032         if (hub->mA_per_port < 500)
1033                 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1034                                 hub->mA_per_port);
1035
1036         ret = hub_hub_status(hub, &hubstatus, &hubchange);
1037         if (ret < 0) {
1038                 message = "can't get hub status";
1039                 goto fail;
1040         }
1041
1042         /* local power status reports aren't always correct */
1043         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1044                 dev_dbg(hub_dev, "local power source is %s\n",
1045                         (hubstatus & HUB_STATUS_LOCAL_POWER)
1046                         ? "lost (inactive)" : "good");
1047
1048         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1049                 dev_dbg(hub_dev, "%sover-current condition exists\n",
1050                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1051
1052         /* set up the interrupt endpoint
1053          * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1054          * bytes as USB2.0[11.12.3] says because some hubs are known
1055          * to send more data (and thus cause overflow). For root hubs,
1056          * maxpktsize is defined in hcd.c's fake endpoint descriptors
1057          * to be big enough for at least USB_MAXCHILDREN ports. */
1058         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1059         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
1060
1061         if (maxp > sizeof(*hub->buffer))
1062                 maxp = sizeof(*hub->buffer);
1063
1064         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1065         if (!hub->urb) {
1066                 message = "couldn't allocate interrupt urb";
1067                 ret = -ENOMEM;
1068                 goto fail;
1069         }
1070
1071         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1072                 hub, endpoint->bInterval);
1073         hub->urb->transfer_dma = hub->buffer_dma;
1074         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1075
1076         /* maybe cycle the hub leds */
1077         if (hub->has_indicators && blinkenlights)
1078                 hub->indicator [0] = INDICATOR_CYCLE;
1079
1080         hub_activate(hub, HUB_INIT);
1081         return 0;
1082
1083 fail:
1084         dev_err (hub_dev, "config failed, %s (err %d)\n",
1085                         message, ret);
1086         /* hub_disconnect() frees urb and descriptor */
1087         return ret;
1088 }
1089
1090 static void hub_release(struct kref *kref)
1091 {
1092         struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1093
1094         usb_put_intf(to_usb_interface(hub->intfdev));
1095         kfree(hub);
1096 }
1097
1098 static unsigned highspeed_hubs;
1099
1100 static void hub_disconnect(struct usb_interface *intf)
1101 {
1102         struct usb_hub *hub = usb_get_intfdata (intf);
1103
1104         /* Take the hub off the event list and don't let it be added again */
1105         spin_lock_irq(&hub_event_lock);
1106         list_del_init(&hub->event_list);
1107         hub->disconnected = 1;
1108         spin_unlock_irq(&hub_event_lock);
1109
1110         /* Disconnect all children and quiesce the hub */
1111         hub->error = 0;
1112         hub_quiesce(hub, HUB_DISCONNECT);
1113
1114         usb_set_intfdata (intf, NULL);
1115
1116         if (hub->hdev->speed == USB_SPEED_HIGH)
1117                 highspeed_hubs--;
1118
1119         usb_free_urb(hub->urb);
1120         kfree(hub->descriptor);
1121         kfree(hub->status);
1122         usb_buffer_free(hub->hdev, sizeof(*hub->buffer), hub->buffer,
1123                         hub->buffer_dma);
1124
1125         kref_put(&hub->kref, hub_release);
1126 }
1127
1128 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1129 {
1130         struct usb_host_interface *desc;
1131         struct usb_endpoint_descriptor *endpoint;
1132         struct usb_device *hdev;
1133         struct usb_hub *hub;
1134
1135         desc = intf->cur_altsetting;
1136         hdev = interface_to_usbdev(intf);
1137
1138         if (hdev->level == MAX_TOPO_LEVEL) {
1139                 dev_err(&intf->dev, "Unsupported bus topology: "
1140                                 "hub nested too deep\n");
1141                 return -E2BIG;
1142         }
1143
1144 #ifdef  CONFIG_USB_OTG_BLACKLIST_HUB
1145         if (hdev->parent) {
1146                 dev_warn(&intf->dev, "ignoring external hub\n");
1147                 return -ENODEV;
1148         }
1149 #endif
1150
1151         /* Some hubs have a subclass of 1, which AFAICT according to the */
1152         /*  specs is not defined, but it works */
1153         if ((desc->desc.bInterfaceSubClass != 0) &&
1154             (desc->desc.bInterfaceSubClass != 1)) {
1155 descriptor_error:
1156                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
1157                 return -EIO;
1158         }
1159
1160         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
1161         if (desc->desc.bNumEndpoints != 1)
1162                 goto descriptor_error;
1163
1164         endpoint = &desc->endpoint[0].desc;
1165
1166         /* If it's not an interrupt in endpoint, we'd better punt! */
1167         if (!usb_endpoint_is_int_in(endpoint))
1168                 goto descriptor_error;
1169
1170         /* We found a hub */
1171         dev_info (&intf->dev, "USB hub found\n");
1172
1173         hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1174         if (!hub) {
1175                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
1176                 return -ENOMEM;
1177         }
1178
1179         kref_init(&hub->kref);
1180         INIT_LIST_HEAD(&hub->event_list);
1181         hub->intfdev = &intf->dev;
1182         hub->hdev = hdev;
1183         INIT_DELAYED_WORK(&hub->leds, led_work);
1184         INIT_DELAYED_WORK(&hub->init_work, NULL);
1185         usb_get_intf(intf);
1186
1187         usb_set_intfdata (intf, hub);
1188         intf->needs_remote_wakeup = 1;
1189
1190         if (hdev->speed == USB_SPEED_HIGH)
1191                 highspeed_hubs++;
1192
1193         if (hub_configure(hub, endpoint) >= 0)
1194                 return 0;
1195
1196         hub_disconnect (intf);
1197         return -ENODEV;
1198 }
1199
1200 static int
1201 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1202 {
1203         struct usb_device *hdev = interface_to_usbdev (intf);
1204
1205         /* assert ifno == 0 (part of hub spec) */
1206         switch (code) {
1207         case USBDEVFS_HUB_PORTINFO: {
1208                 struct usbdevfs_hub_portinfo *info = user_data;
1209                 int i;
1210
1211                 spin_lock_irq(&device_state_lock);
1212                 if (hdev->devnum <= 0)
1213                         info->nports = 0;
1214                 else {
1215                         info->nports = hdev->maxchild;
1216                         for (i = 0; i < info->nports; i++) {
1217                                 if (hdev->children[i] == NULL)
1218                                         info->port[i] = 0;
1219                                 else
1220                                         info->port[i] =
1221                                                 hdev->children[i]->devnum;
1222                         }
1223                 }
1224                 spin_unlock_irq(&device_state_lock);
1225
1226                 return info->nports + 1;
1227                 }
1228
1229         default:
1230                 return -ENOSYS;
1231         }
1232 }
1233
1234
1235 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1236 {
1237         int i;
1238
1239         for (i = 0; i < udev->maxchild; ++i) {
1240                 if (udev->children[i])
1241                         recursively_mark_NOTATTACHED(udev->children[i]);
1242         }
1243         if (udev->state == USB_STATE_SUSPENDED) {
1244                 udev->discon_suspended = 1;
1245                 udev->active_duration -= jiffies;
1246         }
1247         udev->state = USB_STATE_NOTATTACHED;
1248 }
1249
1250 /**
1251  * usb_set_device_state - change a device's current state (usbcore, hcds)
1252  * @udev: pointer to device whose state should be changed
1253  * @new_state: new state value to be stored
1254  *
1255  * udev->state is _not_ fully protected by the device lock.  Although
1256  * most transitions are made only while holding the lock, the state can
1257  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1258  * is so that devices can be marked as disconnected as soon as possible,
1259  * without having to wait for any semaphores to be released.  As a result,
1260  * all changes to any device's state must be protected by the
1261  * device_state_lock spinlock.
1262  *
1263  * Once a device has been added to the device tree, all changes to its state
1264  * should be made using this routine.  The state should _not_ be set directly.
1265  *
1266  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1267  * Otherwise udev->state is set to new_state, and if new_state is
1268  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1269  * to USB_STATE_NOTATTACHED.
1270  */
1271 void usb_set_device_state(struct usb_device *udev,
1272                 enum usb_device_state new_state)
1273 {
1274         unsigned long flags;
1275
1276         spin_lock_irqsave(&device_state_lock, flags);
1277         if (udev->state == USB_STATE_NOTATTACHED)
1278                 ;       /* do nothing */
1279         else if (new_state != USB_STATE_NOTATTACHED) {
1280
1281                 /* root hub wakeup capabilities are managed out-of-band
1282                  * and may involve silicon errata ... ignore them here.
1283                  */
1284                 if (udev->parent) {
1285                         if (udev->state == USB_STATE_SUSPENDED
1286                                         || new_state == USB_STATE_SUSPENDED)
1287                                 ;       /* No change to wakeup settings */
1288                         else if (new_state == USB_STATE_CONFIGURED)
1289                                 device_init_wakeup(&udev->dev,
1290                                         (udev->actconfig->desc.bmAttributes
1291                                          & USB_CONFIG_ATT_WAKEUP));
1292                         else
1293                                 device_init_wakeup(&udev->dev, 0);
1294                 }
1295                 if (udev->state == USB_STATE_SUSPENDED &&
1296                         new_state != USB_STATE_SUSPENDED)
1297                         udev->active_duration -= jiffies;
1298                 else if (new_state == USB_STATE_SUSPENDED &&
1299                                 udev->state != USB_STATE_SUSPENDED)
1300                         udev->active_duration += jiffies;
1301                 udev->state = new_state;
1302         } else
1303                 recursively_mark_NOTATTACHED(udev);
1304         spin_unlock_irqrestore(&device_state_lock, flags);
1305 }
1306
1307 /*
1308  * WUSB devices are simple: they have no hubs behind, so the mapping
1309  * device <-> virtual port number becomes 1:1. Why? to simplify the
1310  * life of the device connection logic in
1311  * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
1312  * handshake we need to assign a temporary address in the unauthorized
1313  * space. For simplicity we use the first virtual port number found to
1314  * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
1315  * and that becomes it's address [X < 128] or its unauthorized address
1316  * [X | 0x80].
1317  *
1318  * We add 1 as an offset to the one-based USB-stack port number
1319  * (zero-based wusb virtual port index) for two reasons: (a) dev addr
1320  * 0 is reserved by USB for default address; (b) Linux's USB stack
1321  * uses always #1 for the root hub of the controller. So USB stack's
1322  * port #1, which is wusb virtual-port #0 has address #2.
1323  */
1324 static void choose_address(struct usb_device *udev)
1325 {
1326         int             devnum;
1327         struct usb_bus  *bus = udev->bus;
1328
1329         /* If khubd ever becomes multithreaded, this will need a lock */
1330         if (udev->wusb) {
1331                 devnum = udev->portnum + 1;
1332                 BUG_ON(test_bit(devnum, bus->devmap.devicemap));
1333         } else {
1334                 /* Try to allocate the next devnum beginning at
1335                  * bus->devnum_next. */
1336                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1337                                             bus->devnum_next);
1338                 if (devnum >= 128)
1339                         devnum = find_next_zero_bit(bus->devmap.devicemap,
1340                                                     128, 1);
1341                 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1342         }
1343         if (devnum < 128) {
1344                 set_bit(devnum, bus->devmap.devicemap);
1345                 udev->devnum = devnum;
1346         }
1347 }
1348
1349 static void release_address(struct usb_device *udev)
1350 {
1351         if (udev->devnum > 0) {
1352                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1353                 udev->devnum = -1;
1354         }
1355 }
1356
1357 static void update_address(struct usb_device *udev, int devnum)
1358 {
1359         /* The address for a WUSB device is managed by wusbcore. */
1360         if (!udev->wusb)
1361                 udev->devnum = devnum;
1362 }
1363
1364 #ifdef  CONFIG_USB_SUSPEND
1365
1366 static void usb_stop_pm(struct usb_device *udev)
1367 {
1368         /* Synchronize with the ksuspend thread to prevent any more
1369          * autosuspend requests from being submitted, and decrement
1370          * the parent's count of unsuspended children.
1371          */
1372         usb_pm_lock(udev);
1373         if (udev->parent && !udev->discon_suspended)
1374                 usb_autosuspend_device(udev->parent);
1375         usb_pm_unlock(udev);
1376
1377         /* Stop any autosuspend requests already submitted */
1378         cancel_rearming_delayed_work(&udev->autosuspend);
1379 }
1380
1381 #else
1382
1383 static inline void usb_stop_pm(struct usb_device *udev)
1384 { }
1385
1386 #endif
1387
1388 /**
1389  * usb_disconnect - disconnect a device (usbcore-internal)
1390  * @pdev: pointer to device being disconnected
1391  * Context: !in_interrupt ()
1392  *
1393  * Something got disconnected. Get rid of it and all of its children.
1394  *
1395  * If *pdev is a normal device then the parent hub must already be locked.
1396  * If *pdev is a root hub then this routine will acquire the
1397  * usb_bus_list_lock on behalf of the caller.
1398  *
1399  * Only hub drivers (including virtual root hub drivers for host
1400  * controllers) should ever call this.
1401  *
1402  * This call is synchronous, and may not be used in an interrupt context.
1403  */
1404 void usb_disconnect(struct usb_device **pdev)
1405 {
1406         struct usb_device       *udev = *pdev;
1407         int                     i;
1408
1409         if (!udev) {
1410                 pr_debug ("%s nodev\n", __func__);
1411                 return;
1412         }
1413
1414         /* mark the device as inactive, so any further urb submissions for
1415          * this device (and any of its children) will fail immediately.
1416          * this quiesces everyting except pending urbs.
1417          */
1418         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1419         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1420
1421         usb_lock_device(udev);
1422
1423         /* Free up all the children before we remove this device */
1424         for (i = 0; i < USB_MAXCHILDREN; i++) {
1425                 if (udev->children[i])
1426                         usb_disconnect(&udev->children[i]);
1427         }
1428
1429         /* deallocate hcd/hardware state ... nuking all pending urbs and
1430          * cleaning up all state associated with the current configuration
1431          * so that the hardware is now fully quiesced.
1432          */
1433         dev_dbg (&udev->dev, "unregistering device\n");
1434         usb_disable_device(udev, 0);
1435         usb_hcd_synchronize_unlinks(udev);
1436
1437         usb_unlock_device(udev);
1438
1439         /* Remove the device-specific files from sysfs.  This must be
1440          * done with udev unlocked, because some of the attribute
1441          * routines try to acquire the device lock.
1442          */
1443         usb_remove_sysfs_dev_files(udev);
1444
1445         /* Unregister the device.  The device driver is responsible
1446          * for removing the device files from usbfs and sysfs and for
1447          * de-configuring the device.
1448          */
1449         device_del(&udev->dev);
1450
1451         /* Free the device number and delete the parent's children[]
1452          * (or root_hub) pointer.
1453          */
1454         release_address(udev);
1455
1456         /* Avoid races with recursively_mark_NOTATTACHED() */
1457         spin_lock_irq(&device_state_lock);
1458         *pdev = NULL;
1459         spin_unlock_irq(&device_state_lock);
1460
1461         usb_stop_pm(udev);
1462
1463         put_device(&udev->dev);
1464 }
1465
1466 #ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
1467 static void show_string(struct usb_device *udev, char *id, char *string)
1468 {
1469         if (!string)
1470                 return;
1471         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1472 }
1473
1474 static void announce_device(struct usb_device *udev)
1475 {
1476         dev_info(&udev->dev, "New USB device found, idVendor=%04x, idProduct=%04x\n",
1477                 le16_to_cpu(udev->descriptor.idVendor),
1478                 le16_to_cpu(udev->descriptor.idProduct));
1479         dev_info(&udev->dev, "New USB device strings: Mfr=%d, Product=%d, "
1480                 "SerialNumber=%d\n",
1481                 udev->descriptor.iManufacturer,
1482                 udev->descriptor.iProduct,
1483                 udev->descriptor.iSerialNumber);
1484         show_string(udev, "Product", udev->product);
1485         show_string(udev, "Manufacturer", udev->manufacturer);
1486         show_string(udev, "SerialNumber", udev->serial);
1487 }
1488 #else
1489 static inline void announce_device(struct usb_device *udev) { }
1490 #endif
1491
1492 #ifdef  CONFIG_USB_OTG
1493 #include "otg_whitelist.h"
1494 #endif
1495
1496 /**
1497  * usb_configure_device_otg - FIXME (usbcore-internal)
1498  * @udev: newly addressed device (in ADDRESS state)
1499  *
1500  * Do configuration for On-The-Go devices
1501  */
1502 static int usb_configure_device_otg(struct usb_device *udev)
1503 {
1504         int err = 0;
1505
1506 #ifdef  CONFIG_USB_OTG
1507         /*
1508          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1509          * to wake us after we've powered off VBUS; and HNP, switching roles
1510          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1511          */
1512         if (!udev->bus->is_b_host
1513                         && udev->config
1514                         && udev->parent == udev->bus->root_hub) {
1515                 struct usb_otg_descriptor       *desc = 0;
1516                 struct usb_bus                  *bus = udev->bus;
1517
1518                 /* descriptor may appear anywhere in config */
1519                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1520                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1521                                         USB_DT_OTG, (void **) &desc) == 0) {
1522                         if (desc->bmAttributes & USB_OTG_HNP) {
1523                                 unsigned                port1 = udev->portnum;
1524
1525                                 dev_info(&udev->dev,
1526                                         "Dual-Role OTG device on %sHNP port\n",
1527                                         (port1 == bus->otg_port)
1528                                                 ? "" : "non-");
1529
1530                                 /* enable HNP before suspend, it's simpler */
1531                                 if (port1 == bus->otg_port)
1532                                         bus->b_hnp_enable = 1;
1533                                 err = usb_control_msg(udev,
1534                                         usb_sndctrlpipe(udev, 0),
1535                                         USB_REQ_SET_FEATURE, 0,
1536                                         bus->b_hnp_enable
1537                                                 ? USB_DEVICE_B_HNP_ENABLE
1538                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1539                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1540                                 if (err < 0) {
1541                                         /* OTG MESSAGE: report errors here,
1542                                          * customize to match your product.
1543                                          */
1544                                         dev_info(&udev->dev,
1545                                                 "can't set HNP mode; %d\n",
1546                                                 err);
1547                                         bus->b_hnp_enable = 0;
1548                                 }
1549                         }
1550                 }
1551         }
1552
1553         if (!is_targeted(udev)) {
1554
1555                 /* Maybe it can talk to us, though we can't talk to it.
1556                  * (Includes HNP test device.)
1557                  */
1558                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1559                         err = usb_port_suspend(udev);
1560                         if (err < 0)
1561                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1562                 }
1563                 err = -ENOTSUPP;
1564                 goto fail;
1565         }
1566 fail:
1567 #endif
1568         return err;
1569 }
1570
1571
1572 /**
1573  * usb_configure_device - Detect and probe device intfs/otg (usbcore-internal)
1574  * @udev: newly addressed device (in ADDRESS state)
1575  *
1576  * This is only called by usb_new_device() and usb_authorize_device()
1577  * and FIXME -- all comments that apply to them apply here wrt to
1578  * environment.
1579  *
1580  * If the device is WUSB and not authorized, we don't attempt to read
1581  * the string descriptors, as they will be errored out by the device
1582  * until it has been authorized.
1583  */
1584 static int usb_configure_device(struct usb_device *udev)
1585 {
1586         int err;
1587
1588         if (udev->config == NULL) {
1589                 err = usb_get_configuration(udev);
1590                 if (err < 0) {
1591                         dev_err(&udev->dev, "can't read configurations, error %d\n",
1592                                 err);
1593                         goto fail;
1594                 }
1595         }
1596         if (udev->wusb == 1 && udev->authorized == 0) {
1597                 udev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1598                 udev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1599                 udev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1600         }
1601         else {
1602                 /* read the standard strings and cache them if present */
1603                 udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1604                 udev->manufacturer = usb_cache_string(udev,
1605                                                       udev->descriptor.iManufacturer);
1606                 udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1607         }
1608         err = usb_configure_device_otg(udev);
1609 fail:
1610         return err;
1611 }
1612
1613
1614 /**
1615  * usb_new_device - perform initial device setup (usbcore-internal)
1616  * @udev: newly addressed device (in ADDRESS state)
1617  *
1618  * This is called with devices which have been enumerated, but not yet
1619  * configured.  The device descriptor is available, but not descriptors
1620  * for any device configuration.  The caller must have locked either
1621  * the parent hub (if udev is a normal device) or else the
1622  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1623  * udev has already been installed, but udev is not yet visible through
1624  * sysfs or other filesystem code.
1625  *
1626  * It will return if the device is configured properly or not.  Zero if
1627  * the interface was registered with the driver core; else a negative
1628  * errno value.
1629  *
1630  * This call is synchronous, and may not be used in an interrupt context.
1631  *
1632  * Only the hub driver or root-hub registrar should ever call this.
1633  */
1634 int usb_new_device(struct usb_device *udev)
1635 {
1636         int err;
1637
1638         usb_detect_quirks(udev);                /* Determine quirks */
1639         err = usb_configure_device(udev);       /* detect & probe dev/intfs */
1640         if (err < 0)
1641                 goto fail;
1642         /* export the usbdev device-node for libusb */
1643         udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
1644                         (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1645
1646         /* Increment the parent's count of unsuspended children */
1647         if (udev->parent)
1648                 usb_autoresume_device(udev->parent);
1649
1650         /* Register the device.  The device driver is responsible
1651          * for adding the device files to sysfs and for configuring
1652          * the device.
1653          */
1654         err = device_add(&udev->dev);
1655         if (err) {
1656                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1657                 goto fail;
1658         }
1659
1660         /* put device-specific files into sysfs */
1661         usb_create_sysfs_dev_files(udev);
1662
1663         /* Tell the world! */
1664         announce_device(udev);
1665         return err;
1666
1667 fail:
1668         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1669         return err;
1670 }
1671
1672
1673 /**
1674  * usb_deauthorize_device - deauthorize a device (usbcore-internal)
1675  * @usb_dev: USB device
1676  *
1677  * Move the USB device to a very basic state where interfaces are disabled
1678  * and the device is in fact unconfigured and unusable.
1679  *
1680  * We share a lock (that we have) with device_del(), so we need to
1681  * defer its call.
1682  */
1683 int usb_deauthorize_device(struct usb_device *usb_dev)
1684 {
1685         unsigned cnt;
1686         usb_lock_device(usb_dev);
1687         if (usb_dev->authorized == 0)
1688                 goto out_unauthorized;
1689         usb_dev->authorized = 0;
1690         usb_set_configuration(usb_dev, -1);
1691         usb_dev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1692         usb_dev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1693         usb_dev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1694         kfree(usb_dev->config);
1695         usb_dev->config = NULL;
1696         for (cnt = 0; cnt < usb_dev->descriptor.bNumConfigurations; cnt++)
1697                 kfree(usb_dev->rawdescriptors[cnt]);
1698         usb_dev->descriptor.bNumConfigurations = 0;
1699         kfree(usb_dev->rawdescriptors);
1700 out_unauthorized:
1701         usb_unlock_device(usb_dev);
1702         return 0;
1703 }
1704
1705
1706 int usb_authorize_device(struct usb_device *usb_dev)
1707 {
1708         int result = 0, c;
1709         usb_lock_device(usb_dev);
1710         if (usb_dev->authorized == 1)
1711                 goto out_authorized;
1712         kfree(usb_dev->product);
1713         usb_dev->product = NULL;
1714         kfree(usb_dev->manufacturer);
1715         usb_dev->manufacturer = NULL;
1716         kfree(usb_dev->serial);
1717         usb_dev->serial = NULL;
1718         result = usb_autoresume_device(usb_dev);
1719         if (result < 0) {
1720                 dev_err(&usb_dev->dev,
1721                         "can't autoresume for authorization: %d\n", result);
1722                 goto error_autoresume;
1723         }
1724         result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
1725         if (result < 0) {
1726                 dev_err(&usb_dev->dev, "can't re-read device descriptor for "
1727                         "authorization: %d\n", result);
1728                 goto error_device_descriptor;
1729         }
1730         usb_dev->authorized = 1;
1731         result = usb_configure_device(usb_dev);
1732         if (result < 0)
1733                 goto error_configure;
1734         /* Choose and set the configuration.  This registers the interfaces
1735          * with the driver core and lets interface drivers bind to them.
1736          */
1737         c = usb_choose_configuration(usb_dev);
1738         if (c >= 0) {
1739                 result = usb_set_configuration(usb_dev, c);
1740                 if (result) {
1741                         dev_err(&usb_dev->dev,
1742                                 "can't set config #%d, error %d\n", c, result);
1743                         /* This need not be fatal.  The user can try to
1744                          * set other configurations. */
1745                 }
1746         }
1747         dev_info(&usb_dev->dev, "authorized to connect\n");
1748 error_configure:
1749 error_device_descriptor:
1750 error_autoresume:
1751 out_authorized:
1752         usb_unlock_device(usb_dev);     // complements locktree
1753         return result;
1754 }
1755
1756
1757 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
1758 static unsigned hub_is_wusb(struct usb_hub *hub)
1759 {
1760         struct usb_hcd *hcd;
1761         if (hub->hdev->parent != NULL)  /* not a root hub? */
1762                 return 0;
1763         hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
1764         return hcd->wireless;
1765 }
1766
1767
1768 #define PORT_RESET_TRIES        5
1769 #define SET_ADDRESS_TRIES       2
1770 #define GET_DESCRIPTOR_TRIES    2
1771 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1772 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1773
1774 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1775 #define HUB_SHORT_RESET_TIME    10
1776 #define HUB_LONG_RESET_TIME     200
1777 #define HUB_RESET_TIMEOUT       500
1778
1779 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1780                                 struct usb_device *udev, unsigned int delay)
1781 {
1782         int delay_time, ret;
1783         u16 portstatus;
1784         u16 portchange;
1785
1786         for (delay_time = 0;
1787                         delay_time < HUB_RESET_TIMEOUT;
1788                         delay_time += delay) {
1789                 /* wait to give the device a chance to reset */
1790                 msleep(delay);
1791
1792                 /* read and decode port status */
1793                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1794                 if (ret < 0)
1795                         return ret;
1796
1797                 /* Device went away? */
1798                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1799                         return -ENOTCONN;
1800
1801                 /* bomb out completely if the connection bounced */
1802                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1803                         return -ENOTCONN;
1804
1805                 /* if we`ve finished resetting, then break out of the loop */
1806                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1807                     (portstatus & USB_PORT_STAT_ENABLE)) {
1808                         if (hub_is_wusb(hub))
1809                                 udev->speed = USB_SPEED_VARIABLE;
1810                         else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1811                                 udev->speed = USB_SPEED_HIGH;
1812                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1813                                 udev->speed = USB_SPEED_LOW;
1814                         else
1815                                 udev->speed = USB_SPEED_FULL;
1816                         return 0;
1817                 }
1818
1819                 /* switch to the long delay after two short delay failures */
1820                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1821                         delay = HUB_LONG_RESET_TIME;
1822
1823                 dev_dbg (hub->intfdev,
1824                         "port %d not reset yet, waiting %dms\n",
1825                         port1, delay);
1826         }
1827
1828         return -EBUSY;
1829 }
1830
1831 static int hub_port_reset(struct usb_hub *hub, int port1,
1832                                 struct usb_device *udev, unsigned int delay)
1833 {
1834         int i, status;
1835
1836         /* Block EHCI CF initialization during the port reset.
1837          * Some companion controllers don't like it when they mix.
1838          */
1839         down_read(&ehci_cf_port_reset_rwsem);
1840
1841         /* Reset the port */
1842         for (i = 0; i < PORT_RESET_TRIES; i++) {
1843                 status = set_port_feature(hub->hdev,
1844                                 port1, USB_PORT_FEAT_RESET);
1845                 if (status)
1846                         dev_err(hub->intfdev,
1847                                         "cannot reset port %d (err = %d)\n",
1848                                         port1, status);
1849                 else {
1850                         status = hub_port_wait_reset(hub, port1, udev, delay);
1851                         if (status && status != -ENOTCONN)
1852                                 dev_dbg(hub->intfdev,
1853                                                 "port_wait_reset: err = %d\n",
1854                                                 status);
1855                 }
1856
1857                 /* return on disconnect or reset */
1858                 switch (status) {
1859                 case 0:
1860                         /* TRSTRCY = 10 ms; plus some extra */
1861                         msleep(10 + 40);
1862                         update_address(udev, 0);
1863                         /* FALL THROUGH */
1864                 case -ENOTCONN:
1865                 case -ENODEV:
1866                         clear_port_feature(hub->hdev,
1867                                 port1, USB_PORT_FEAT_C_RESET);
1868                         /* FIXME need disconnect() for NOTATTACHED device */
1869                         usb_set_device_state(udev, status
1870                                         ? USB_STATE_NOTATTACHED
1871                                         : USB_STATE_DEFAULT);
1872                         goto done;
1873                 }
1874
1875                 dev_dbg (hub->intfdev,
1876                         "port %d not enabled, trying reset again...\n",
1877                         port1);
1878                 delay = HUB_LONG_RESET_TIME;
1879         }
1880
1881         dev_err (hub->intfdev,
1882                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1883                 port1);
1884
1885  done:
1886         up_read(&ehci_cf_port_reset_rwsem);
1887         return status;
1888 }
1889
1890 #ifdef  CONFIG_PM
1891
1892 #define MASK_BITS       (USB_PORT_STAT_POWER | USB_PORT_STAT_CONNECTION | \
1893                                 USB_PORT_STAT_SUSPEND)
1894 #define WANT_BITS       (USB_PORT_STAT_POWER | USB_PORT_STAT_CONNECTION)
1895
1896 /* Determine whether the device on a port is ready for a normal resume,
1897  * is ready for a reset-resume, or should be disconnected.
1898  */
1899 static int check_port_resume_type(struct usb_device *udev,
1900                 struct usb_hub *hub, int port1,
1901                 int status, unsigned portchange, unsigned portstatus)
1902 {
1903         /* Is the device still present? */
1904         if (status || (portstatus & MASK_BITS) != WANT_BITS) {
1905                 if (status >= 0)
1906                         status = -ENODEV;
1907         }
1908
1909         /* Can't do a normal resume if the port isn't enabled,
1910          * so try a reset-resume instead.
1911          */
1912         else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
1913                 if (udev->persist_enabled)
1914                         udev->reset_resume = 1;
1915                 else
1916                         status = -ENODEV;
1917         }
1918
1919         if (status) {
1920                 dev_dbg(hub->intfdev,
1921                                 "port %d status %04x.%04x after resume, %d\n",
1922                                 port1, portchange, portstatus, status);
1923         } else if (udev->reset_resume) {
1924
1925                 /* Late port handoff can set status-change bits */
1926                 if (portchange & USB_PORT_STAT_C_CONNECTION)
1927                         clear_port_feature(hub->hdev, port1,
1928                                         USB_PORT_FEAT_C_CONNECTION);
1929                 if (portchange & USB_PORT_STAT_C_ENABLE)
1930                         clear_port_feature(hub->hdev, port1,
1931                                         USB_PORT_FEAT_C_ENABLE);
1932         }
1933
1934         return status;
1935 }
1936
1937 #ifdef  CONFIG_USB_SUSPEND
1938
1939 /*
1940  * usb_port_suspend - suspend a usb device's upstream port
1941  * @udev: device that's no longer in active use, not a root hub
1942  * Context: must be able to sleep; device not locked; pm locks held
1943  *
1944  * Suspends a USB device that isn't in active use, conserving power.
1945  * Devices may wake out of a suspend, if anything important happens,
1946  * using the remote wakeup mechanism.  They may also be taken out of
1947  * suspend by the host, using usb_port_resume().  It's also routine
1948  * to disconnect devices while they are suspended.
1949  *
1950  * This only affects the USB hardware for a device; its interfaces
1951  * (and, for hubs, child devices) must already have been suspended.
1952  *
1953  * Selective port suspend reduces power; most suspended devices draw
1954  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1955  * All devices below the suspended port are also suspended.
1956  *
1957  * Devices leave suspend state when the host wakes them up.  Some devices
1958  * also support "remote wakeup", where the device can activate the USB
1959  * tree above them to deliver data, such as a keypress or packet.  In
1960  * some cases, this wakes the USB host.
1961  *
1962  * Suspending OTG devices may trigger HNP, if that's been enabled
1963  * between a pair of dual-role devices.  That will change roles, such
1964  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1965  *
1966  * Devices on USB hub ports have only one "suspend" state, corresponding
1967  * to ACPI D2, "may cause the device to lose some context".
1968  * State transitions include:
1969  *
1970  *   - suspend, resume ... when the VBUS power link stays live
1971  *   - suspend, disconnect ... VBUS lost
1972  *
1973  * Once VBUS drop breaks the circuit, the port it's using has to go through
1974  * normal re-enumeration procedures, starting with enabling VBUS power.
1975  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1976  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1977  * timer, no SRP, no requests through sysfs.
1978  *
1979  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1980  * the root hub for their bus goes into global suspend ... so we don't
1981  * (falsely) update the device power state to say it suspended.
1982  *
1983  * Returns 0 on success, else negative errno.
1984  */
1985 int usb_port_suspend(struct usb_device *udev)
1986 {
1987         struct usb_hub  *hub = hdev_to_hub(udev->parent);
1988         int             port1 = udev->portnum;
1989         int             status;
1990
1991         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1992
1993         /* enable remote wakeup when appropriate; this lets the device
1994          * wake up the upstream hub (including maybe the root hub).
1995          *
1996          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1997          * we don't explicitly enable it here.
1998          */
1999         if (udev->do_remote_wakeup) {
2000                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2001                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
2002                                 USB_DEVICE_REMOTE_WAKEUP, 0,
2003                                 NULL, 0,
2004                                 USB_CTRL_SET_TIMEOUT);
2005                 if (status)
2006                         dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
2007                                         status);
2008         }
2009
2010         /* see 7.1.7.6 */
2011         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
2012         if (status) {
2013                 dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",
2014                                 port1, status);
2015                 /* paranoia:  "should not happen" */
2016                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2017                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
2018                                 USB_DEVICE_REMOTE_WAKEUP, 0,
2019                                 NULL, 0,
2020                                 USB_CTRL_SET_TIMEOUT);
2021         } else {
2022                 /* device has up to 10 msec to fully suspend */
2023                 dev_dbg(&udev->dev, "usb %ssuspend\n",
2024                                 udev->auto_pm ? "auto-" : "");
2025                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
2026                 msleep(10);
2027         }
2028         return status;
2029 }
2030
2031 /*
2032  * If the USB "suspend" state is in use (rather than "global suspend"),
2033  * many devices will be individually taken out of suspend state using
2034  * special "resume" signaling.  This routine kicks in shortly after
2035  * hardware resume signaling is finished, either because of selective
2036  * resume (by host) or remote wakeup (by device) ... now see what changed
2037  * in the tree that's rooted at this device.
2038  *
2039  * If @udev->reset_resume is set then the device is reset before the
2040  * status check is done.
2041  */
2042 static int finish_port_resume(struct usb_device *udev)
2043 {
2044         int     status = 0;
2045         u16     devstatus;
2046
2047         /* caller owns the udev device lock */
2048         dev_dbg(&udev->dev, "finish %sresume\n",
2049                         udev->reset_resume ? "reset-" : "");
2050
2051         /* usb ch9 identifies four variants of SUSPENDED, based on what
2052          * state the device resumes to.  Linux currently won't see the
2053          * first two on the host side; they'd be inside hub_port_init()
2054          * during many timeouts, but khubd can't suspend until later.
2055          */
2056         usb_set_device_state(udev, udev->actconfig
2057                         ? USB_STATE_CONFIGURED
2058                         : USB_STATE_ADDRESS);
2059
2060         /* 10.5.4.5 says not to reset a suspended port if the attached
2061          * device is enabled for remote wakeup.  Hence the reset
2062          * operation is carried out here, after the port has been
2063          * resumed.
2064          */
2065         if (udev->reset_resume)
2066  retry_reset_resume:
2067                 status = usb_reset_and_verify_device(udev);
2068
2069         /* 10.5.4.5 says be sure devices in the tree are still there.
2070          * For now let's assume the device didn't go crazy on resume,
2071          * and device drivers will know about any resume quirks.
2072          */
2073         if (status == 0) {
2074                 devstatus = 0;
2075                 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
2076                 if (status >= 0)
2077                         status = (status > 0 ? 0 : -ENODEV);
2078
2079                 /* If a normal resume failed, try doing a reset-resume */
2080                 if (status && !udev->reset_resume && udev->persist_enabled) {
2081                         dev_dbg(&udev->dev, "retry with reset-resume\n");
2082                         udev->reset_resume = 1;
2083                         goto retry_reset_resume;
2084                 }
2085         }
2086
2087         if (status) {
2088                 dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
2089                                 status);
2090         } else if (udev->actconfig) {
2091                 le16_to_cpus(&devstatus);
2092                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
2093                         status = usb_control_msg(udev,
2094                                         usb_sndctrlpipe(udev, 0),
2095                                         USB_REQ_CLEAR_FEATURE,
2096                                                 USB_RECIP_DEVICE,
2097                                         USB_DEVICE_REMOTE_WAKEUP, 0,
2098                                         NULL, 0,
2099                                         USB_CTRL_SET_TIMEOUT);
2100                         if (status)
2101                                 dev_dbg(&udev->dev, "disable remote "
2102                                         "wakeup, status %d\n", status);
2103                 }
2104                 status = 0;
2105         }
2106         return status;
2107 }
2108
2109 /*
2110  * usb_port_resume - re-activate a suspended usb device's upstream port
2111  * @udev: device to re-activate, not a root hub
2112  * Context: must be able to sleep; device not locked; pm locks held
2113  *
2114  * This will re-activate the suspended device, increasing power usage
2115  * while letting drivers communicate again with its endpoints.
2116  * USB resume explicitly guarantees that the power session between
2117  * the host and the device is the same as it was when the device
2118  * suspended.
2119  *
2120  * If @udev->reset_resume is set then this routine won't check that the
2121  * port is still enabled.  Furthermore, finish_port_resume() above will
2122  * reset @udev.  The end result is that a broken power session can be
2123  * recovered and @udev will appear to persist across a loss of VBUS power.
2124  *
2125  * For example, if a host controller doesn't maintain VBUS suspend current
2126  * during a system sleep or is reset when the system wakes up, all the USB
2127  * power sessions below it will be broken.  This is especially troublesome
2128  * for mass-storage devices containing mounted filesystems, since the
2129  * device will appear to have disconnected and all the memory mappings
2130  * to it will be lost.  Using the USB_PERSIST facility, the device can be
2131  * made to appear as if it had not disconnected.
2132  *
2133  * This facility can be dangerous.  Although usb_reset_and_verify_device() makes
2134  * every effort to insure that the same device is present after the
2135  * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
2136  * quite possible for a device to remain unaltered but its media to be
2137  * changed.  If the user replaces a flash memory card while the system is
2138  * asleep, he will have only himself to blame when the filesystem on the
2139  * new card is corrupted and the system crashes.
2140  *
2141  * Returns 0 on success, else negative errno.
2142  */
2143 int usb_port_resume(struct usb_device *udev)
2144 {
2145         struct usb_hub  *hub = hdev_to_hub(udev->parent);
2146         int             port1 = udev->portnum;
2147         int             status;
2148         u16             portchange, portstatus;
2149
2150         /* Skip the initial Clear-Suspend step for a remote wakeup */
2151         status = hub_port_status(hub, port1, &portstatus, &portchange);
2152         if (status == 0 && !(portstatus & USB_PORT_STAT_SUSPEND))
2153                 goto SuspendCleared;
2154
2155         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
2156
2157         set_bit(port1, hub->busy_bits);
2158
2159         /* see 7.1.7.7; affects power usage, but not budgeting */
2160         status = clear_port_feature(hub->hdev,
2161                         port1, USB_PORT_FEAT_SUSPEND);
2162         if (status) {
2163                 dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
2164                                 port1, status);
2165         } else {
2166                 /* drive resume for at least 20 msec */
2167                 dev_dbg(&udev->dev, "usb %sresume\n",
2168                                 udev->auto_pm ? "auto-" : "");
2169                 msleep(25);
2170
2171                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
2172                  * stop resume signaling.  Then finish the resume
2173                  * sequence.
2174                  */
2175                 status = hub_port_status(hub, port1, &portstatus, &portchange);
2176
2177                 /* TRSMRCY = 10 msec */
2178                 msleep(10);
2179         }
2180
2181  SuspendCleared:
2182         if (status == 0) {
2183                 if (portchange & USB_PORT_STAT_C_SUSPEND)
2184                         clear_port_feature(hub->hdev, port1,
2185                                         USB_PORT_FEAT_C_SUSPEND);
2186         }
2187
2188         clear_bit(port1, hub->busy_bits);
2189
2190         status = check_port_resume_type(udev,
2191                         hub, port1, status, portchange, portstatus);
2192         if (status == 0)
2193                 status = finish_port_resume(udev);
2194         if (status < 0) {
2195                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2196                 hub_port_logical_disconnect(hub, port1);
2197         }
2198         return status;
2199 }
2200
2201 /* caller has locked udev */
2202 static int remote_wakeup(struct usb_device *udev)
2203 {
2204         int     status = 0;
2205
2206         if (udev->state == USB_STATE_SUSPENDED) {
2207                 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
2208                 usb_mark_last_busy(udev);
2209                 status = usb_external_resume_device(udev);
2210         }
2211         return status;
2212 }
2213
2214 #else   /* CONFIG_USB_SUSPEND */
2215
2216 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
2217
2218 int usb_port_suspend(struct usb_device *udev)
2219 {
2220         return 0;
2221 }
2222
2223 /* However we may need to do a reset-resume */
2224
2225 int usb_port_resume(struct usb_device *udev)
2226 {
2227         struct usb_hub  *hub = hdev_to_hub(udev->parent);
2228         int             port1 = udev->portnum;
2229         int             status;
2230         u16             portchange, portstatus;
2231
2232         status = hub_port_status(hub, port1, &portstatus, &portchange);
2233         status = check_port_resume_type(udev,
2234                         hub, port1, status, portchange, portstatus);
2235
2236         if (status) {
2237                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2238                 hub_port_logical_disconnect(hub, port1);
2239         } else if (udev->reset_resume) {
2240                 dev_dbg(&udev->dev, "reset-resume\n");
2241                 status = usb_reset_and_verify_device(udev);
2242         }
2243         return status;
2244 }
2245
2246 static inline int remote_wakeup(struct usb_device *udev)
2247 {
2248         return 0;
2249 }
2250
2251 #endif
2252
2253 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
2254 {
2255         struct usb_hub          *hub = usb_get_intfdata (intf);
2256         struct usb_device       *hdev = hub->hdev;
2257         unsigned                port1;
2258
2259         /* fail if children aren't already suspended */
2260         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
2261                 struct usb_device       *udev;
2262
2263                 udev = hdev->children [port1-1];
2264                 if (udev && udev->can_submit) {
2265                         if (!hdev->auto_pm)
2266                                 dev_dbg(&intf->dev, "port %d nyet suspended\n",
2267                                                 port1);
2268                         return -EBUSY;
2269                 }
2270         }
2271
2272         dev_dbg(&intf->dev, "%s\n", __func__);
2273
2274         /* stop khubd and related activity */
2275         hub_quiesce(hub, HUB_SUSPEND);
2276         return 0;
2277 }
2278
2279 static int hub_resume(struct usb_interface *intf)
2280 {
2281         struct usb_hub *hub = usb_get_intfdata(intf);
2282
2283         dev_dbg(&intf->dev, "%s\n", __func__);
2284         hub_activate(hub, HUB_RESUME);
2285         return 0;
2286 }
2287
2288 static int hub_reset_resume(struct usb_interface *intf)
2289 {
2290         struct usb_hub *hub = usb_get_intfdata(intf);
2291
2292         dev_dbg(&intf->dev, "%s\n", __func__);
2293         hub_activate(hub, HUB_RESET_RESUME);
2294         return 0;
2295 }
2296
2297 /**
2298  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
2299  * @rhdev: struct usb_device for the root hub
2300  *
2301  * The USB host controller driver calls this function when its root hub
2302  * is resumed and Vbus power has been interrupted or the controller
2303  * has been reset.  The routine marks @rhdev as having lost power.
2304  * When the hub driver is resumed it will take notice and carry out
2305  * power-session recovery for all the "USB-PERSIST"-enabled child devices;
2306  * the others will be disconnected.
2307  */
2308 void usb_root_hub_lost_power(struct usb_device *rhdev)
2309 {
2310         dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
2311         rhdev->reset_resume = 1;
2312 }
2313 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
2314
2315 #else   /* CONFIG_PM */
2316
2317 static inline int remote_wakeup(struct usb_device *udev)
2318 {
2319         return 0;
2320 }
2321
2322 #define hub_suspend             NULL
2323 #define hub_resume              NULL
2324 #define hub_reset_resume        NULL
2325 #endif
2326
2327
2328 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2329  *
2330  * Between connect detection and reset signaling there must be a delay
2331  * of 100ms at least for debounce and power-settling.  The corresponding
2332  * timer shall restart whenever the downstream port detects a disconnect.
2333  * 
2334  * Apparently there are some bluetooth and irda-dongles and a number of
2335  * low-speed devices for which this debounce period may last over a second.
2336  * Not covered by the spec - but easy to deal with.
2337  *
2338  * This implementation uses a 1500ms total debounce timeout; if the
2339  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2340  * every 25ms for transient disconnects.  When the port status has been
2341  * unchanged for 100ms it returns the port status.
2342  */
2343 static int hub_port_debounce(struct usb_hub *hub, int port1)
2344 {
2345         int ret;
2346         int total_time, stable_time = 0;
2347         u16 portchange, portstatus;
2348         unsigned connection = 0xffff;
2349
2350         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2351                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2352                 if (ret < 0)
2353                         return ret;
2354
2355                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2356                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2357                         stable_time += HUB_DEBOUNCE_STEP;
2358                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2359                                 break;
2360                 } else {
2361                         stable_time = 0;
2362                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2363                 }
2364
2365                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2366                         clear_port_feature(hub->hdev, port1,
2367                                         USB_PORT_FEAT_C_CONNECTION);
2368                 }
2369
2370                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2371                         break;
2372                 msleep(HUB_DEBOUNCE_STEP);
2373         }
2374
2375         dev_dbg (hub->intfdev,
2376                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2377                 port1, total_time, stable_time, portstatus);
2378
2379         if (stable_time < HUB_DEBOUNCE_STABLE)
2380                 return -ETIMEDOUT;
2381         return portstatus;
2382 }
2383
2384 void usb_ep0_reinit(struct usb_device *udev)
2385 {
2386         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2387         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2388         usb_enable_endpoint(udev, &udev->ep0);
2389 }
2390 EXPORT_SYMBOL_GPL(usb_ep0_reinit);
2391
2392 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2393 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2394
2395 static int hub_set_address(struct usb_device *udev, int devnum)
2396 {
2397         int retval;
2398
2399         if (devnum <= 1)
2400                 return -EINVAL;
2401         if (udev->state == USB_STATE_ADDRESS)
2402                 return 0;
2403         if (udev->state != USB_STATE_DEFAULT)
2404                 return -EINVAL;
2405         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2406                 USB_REQ_SET_ADDRESS, 0, devnum, 0,
2407                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2408         if (retval == 0) {
2409                 /* Device now using proper address. */
2410                 update_address(udev, devnum);
2411                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2412                 usb_ep0_reinit(udev);
2413         }
2414         return retval;
2415 }
2416
2417 /* Reset device, (re)assign address, get device descriptor.
2418  * Device connection must be stable, no more debouncing needed.
2419  * Returns device in USB_STATE_ADDRESS, except on error.
2420  *
2421  * If this is called for an already-existing device (as part of
2422  * usb_reset_and_verify_device), the caller must own the device lock.  For a
2423  * newly detected device that is not accessible through any global
2424  * pointers, it's not necessary to lock the device.
2425  */
2426 static int
2427 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2428                 int retry_counter)
2429 {
2430         static DEFINE_MUTEX(usb_address0_mutex);
2431
2432         struct usb_device       *hdev = hub->hdev;
2433         int                     i, j, retval;
2434         unsigned                delay = HUB_SHORT_RESET_TIME;
2435         enum usb_device_speed   oldspeed = udev->speed;
2436         char                    *speed, *type;
2437         int                     devnum = udev->devnum;
2438
2439         /* root hub ports have a slightly longer reset period
2440          * (from USB 2.0 spec, section 7.1.7.5)
2441          */
2442         if (!hdev->parent) {
2443                 delay = HUB_ROOT_RESET_TIME;
2444                 if (port1 == hdev->bus->otg_port)
2445                         hdev->bus->b_hnp_enable = 0;
2446         }
2447
2448         /* Some low speed devices have problems with the quick delay, so */
2449         /*  be a bit pessimistic with those devices. RHbug #23670 */
2450         if (oldspeed == USB_SPEED_LOW)
2451                 delay = HUB_LONG_RESET_TIME;
2452
2453         mutex_lock(&usb_address0_mutex);
2454
2455         /* Reset the device; full speed may morph to high speed */
2456         retval = hub_port_reset(hub, port1, udev, delay);
2457         if (retval < 0)         /* error or disconnect */
2458                 goto fail;
2459                                 /* success, speed is known */
2460         retval = -ENODEV;
2461
2462         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2463                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2464                 goto fail;
2465         }
2466         oldspeed = udev->speed;
2467
2468         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2469          * it's fixed size except for full speed devices.
2470          * For Wireless USB devices, ep0 max packet is always 512 (tho
2471          * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2472          */
2473         switch (udev->speed) {
2474         case USB_SPEED_VARIABLE:        /* fixed at 512 */
2475                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(512);
2476                 break;
2477         case USB_SPEED_HIGH:            /* fixed at 64 */
2478                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2479                 break;
2480         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2481                 /* to determine the ep0 maxpacket size, try to read
2482                  * the device descriptor to get bMaxPacketSize0 and
2483                  * then correct our initial guess.
2484                  */
2485                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2486                 break;
2487         case USB_SPEED_LOW:             /* fixed at 8 */
2488                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2489                 break;
2490         default:
2491                 goto fail;
2492         }
2493  
2494         type = "";
2495         switch (udev->speed) {
2496         case USB_SPEED_LOW:     speed = "low";  break;
2497         case USB_SPEED_FULL:    speed = "full"; break;
2498         case USB_SPEED_HIGH:    speed = "high"; break;
2499         case USB_SPEED_VARIABLE:
2500                                 speed = "variable";
2501                                 type = "Wireless ";
2502                                 break;
2503         default:                speed = "?";    break;
2504         }
2505         dev_info (&udev->dev,
2506                   "%s %s speed %sUSB device using %s and address %d\n",
2507                   (udev->config) ? "reset" : "new", speed, type,
2508                   udev->bus->controller->driver->name, devnum);
2509
2510         /* Set up TT records, if needed  */
2511         if (hdev->tt) {
2512                 udev->tt = hdev->tt;
2513                 udev->ttport = hdev->ttport;
2514         } else if (udev->speed != USB_SPEED_HIGH
2515                         && hdev->speed == USB_SPEED_HIGH) {
2516                 udev->tt = &hub->tt;
2517                 udev->ttport = port1;
2518         }
2519  
2520         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2521          * Because device hardware and firmware is sometimes buggy in
2522          * this area, and this is how Linux has done it for ages.
2523          * Change it cautiously.
2524          *
2525          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2526          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2527          * so it may help with some non-standards-compliant devices.
2528          * Otherwise we start with SET_ADDRESS and then try to read the
2529          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2530          * value.
2531          */
2532         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2533                 if (USE_NEW_SCHEME(retry_counter)) {
2534                         struct usb_device_descriptor *buf;
2535                         int r = 0;
2536
2537 #define GET_DESCRIPTOR_BUFSIZE  64
2538                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2539                         if (!buf) {
2540                                 retval = -ENOMEM;
2541                                 continue;
2542                         }
2543
2544                         /* Retry on all errors; some devices are flakey.
2545                          * 255 is for WUSB devices, we actually need to use
2546                          * 512 (WUSB1.0[4.8.1]).
2547                          */
2548                         for (j = 0; j < 3; ++j) {
2549                                 buf->bMaxPacketSize0 = 0;
2550                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2551                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2552                                         USB_DT_DEVICE << 8, 0,
2553                                         buf, GET_DESCRIPTOR_BUFSIZE,
2554                                         initial_descriptor_timeout);
2555                                 switch (buf->bMaxPacketSize0) {
2556                                 case 8: case 16: case 32: case 64: case 255:
2557                                         if (buf->bDescriptorType ==
2558                                                         USB_DT_DEVICE) {
2559                                                 r = 0;
2560                                                 break;
2561                                         }
2562                                         /* FALL THROUGH */
2563                                 default:
2564                                         if (r == 0)
2565                                                 r = -EPROTO;
2566                                         break;
2567                                 }
2568                                 if (r == 0)
2569                                         break;
2570                         }
2571                         udev->descriptor.bMaxPacketSize0 =
2572                                         buf->bMaxPacketSize0;
2573                         kfree(buf);
2574
2575                         retval = hub_port_reset(hub, port1, udev, delay);
2576                         if (retval < 0)         /* error or disconnect */
2577                                 goto fail;
2578                         if (oldspeed != udev->speed) {
2579                                 dev_dbg(&udev->dev,
2580                                         "device reset changed speed!\n");
2581                                 retval = -ENODEV;
2582                                 goto fail;
2583                         }
2584                         if (r) {
2585                                 dev_err(&udev->dev, "device descriptor "
2586                                                 "read/%s, error %d\n",
2587                                                 "64", r);
2588                                 retval = -EMSGSIZE;
2589                                 continue;
2590                         }
2591 #undef GET_DESCRIPTOR_BUFSIZE
2592                 }
2593
2594                 /*
2595                  * If device is WUSB, we already assigned an
2596                  * unauthorized address in the Connect Ack sequence;
2597                  * authorization will assign the final address.
2598                  */
2599                 if (udev->wusb == 0) {
2600                         for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2601                                 retval = hub_set_address(udev, devnum);
2602                                 if (retval >= 0)
2603                                         break;
2604                                 msleep(200);
2605                         }
2606                         if (retval < 0) {
2607                                 dev_err(&udev->dev,
2608                                         "device not accepting address %d, error %d\n",
2609                                         devnum, retval);
2610                                 goto fail;
2611                         }
2612
2613                         /* cope with hardware quirkiness:
2614                          *  - let SET_ADDRESS settle, some device hardware wants it
2615                          *  - read ep0 maxpacket even for high and low speed,
2616                          */
2617                         msleep(10);
2618                         if (USE_NEW_SCHEME(retry_counter))
2619                                 break;
2620                 }
2621
2622                 retval = usb_get_device_descriptor(udev, 8);
2623                 if (retval < 8) {
2624                         dev_err(&udev->dev, "device descriptor "
2625                                         "read/%s, error %d\n",
2626                                         "8", retval);
2627                         if (retval >= 0)
2628                                 retval = -EMSGSIZE;
2629                 } else {
2630                         retval = 0;
2631                         break;
2632                 }
2633         }
2634         if (retval)
2635                 goto fail;
2636
2637         i = udev->descriptor.bMaxPacketSize0 == 0xff?   /* wusb device? */
2638             512 : udev->descriptor.bMaxPacketSize0;
2639         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2640                 if (udev->speed != USB_SPEED_FULL ||
2641                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2642                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2643                         retval = -EMSGSIZE;
2644                         goto fail;
2645                 }
2646                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2647                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2648                 usb_ep0_reinit(udev);
2649         }
2650   
2651         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2652         if (retval < (signed)sizeof(udev->descriptor)) {
2653                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2654                         "all", retval);
2655                 if (retval >= 0)
2656                         retval = -ENOMSG;
2657                 goto fail;
2658         }
2659
2660         retval = 0;
2661
2662 fail:
2663         if (retval) {
2664                 hub_port_disable(hub, port1, 0);
2665                 update_address(udev, devnum);   /* for disconnect processing */
2666         }
2667         mutex_unlock(&usb_address0_mutex);
2668         return retval;
2669 }
2670
2671 static void
2672 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2673 {
2674         struct usb_qualifier_descriptor *qual;
2675         int                             status;
2676
2677         qual = kmalloc (sizeof *qual, GFP_KERNEL);
2678         if (qual == NULL)
2679                 return;
2680
2681         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2682                         qual, sizeof *qual);
2683         if (status == sizeof *qual) {
2684                 dev_info(&udev->dev, "not running at top speed; "
2685                         "connect to a high speed hub\n");
2686                 /* hub LEDs are probably harder to miss than syslog */
2687                 if (hub->has_indicators) {
2688                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2689                         schedule_delayed_work (&hub->leds, 0);
2690                 }
2691         }
2692         kfree(qual);
2693 }
2694
2695 static unsigned
2696 hub_power_remaining (struct usb_hub *hub)
2697 {
2698         struct usb_device *hdev = hub->hdev;
2699         int remaining;
2700         int port1;
2701
2702         if (!hub->limited_power)
2703                 return 0;
2704
2705         remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2706         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2707                 struct usb_device       *udev = hdev->children[port1 - 1];
2708                 int                     delta;
2709
2710                 if (!udev)
2711                         continue;
2712
2713                 /* Unconfigured devices may not use more than 100mA,
2714                  * or 8mA for OTG ports */
2715                 if (udev->actconfig)
2716                         delta = udev->actconfig->desc.bMaxPower * 2;
2717                 else if (port1 != udev->bus->otg_port || hdev->parent)
2718                         delta = 100;
2719                 else
2720                         delta = 8;
2721                 if (delta > hub->mA_per_port)
2722                         dev_warn(&udev->dev, "%dmA is over %umA budget "
2723                                         "for port %d!\n",
2724                                         delta, hub->mA_per_port, port1);
2725                 remaining -= delta;
2726         }
2727         if (remaining < 0) {
2728                 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2729                         - remaining);
2730                 remaining = 0;
2731         }
2732         return remaining;
2733 }
2734
2735 /* Handle physical or logical connection change events.
2736  * This routine is called when:
2737  *      a port connection-change occurs;
2738  *      a port enable-change occurs (often caused by EMI);
2739  *      usb_reset_and_verify_device() encounters changed descriptors (as from
2740  *              a firmware download)
2741  * caller already locked the hub
2742  */
2743 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2744                                         u16 portstatus, u16 portchange)
2745 {
2746         struct usb_device *hdev = hub->hdev;
2747         struct device *hub_dev = hub->intfdev;
2748         struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
2749         unsigned wHubCharacteristics =
2750                         le16_to_cpu(hub->descriptor->wHubCharacteristics);
2751         struct usb_device *udev;
2752         int status, i;
2753
2754         dev_dbg (hub_dev,
2755                 "port %d, status %04x, change %04x, %s\n",
2756                 port1, portstatus, portchange, portspeed (portstatus));
2757
2758         if (hub->has_indicators) {
2759                 set_port_led(hub, port1, HUB_LED_AUTO);
2760                 hub->indicator[port1-1] = INDICATOR_AUTO;
2761         }
2762
2763 #ifdef  CONFIG_USB_OTG
2764         /* during HNP, don't repeat the debounce */
2765         if (hdev->bus->is_b_host)
2766                 portchange &= ~(USB_PORT_STAT_C_CONNECTION |
2767                                 USB_PORT_STAT_C_ENABLE);
2768 #endif
2769
2770         /* Try to resuscitate an existing device */
2771         udev = hdev->children[port1-1];
2772         if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
2773                         udev->state != USB_STATE_NOTATTACHED) {
2774                 usb_lock_device(udev);
2775                 if (portstatus & USB_PORT_STAT_ENABLE) {
2776                         status = 0;             /* Nothing to do */
2777
2778 #ifdef CONFIG_USB_SUSPEND
2779                 } else if (udev->state == USB_STATE_SUSPENDED &&
2780                                 udev->persist_enabled) {
2781                         /* For a suspended device, treat this as a
2782                          * remote wakeup event.
2783                          */
2784                         if (udev->do_remote_wakeup)
2785                                 status = remote_wakeup(udev);
2786
2787                         /* Otherwise leave it be; devices can't tell the
2788                          * difference between suspended and disabled.
2789                          */
2790                         else
2791                                 status = 0;
2792 #endif
2793
2794                 } else {
2795                         status = -ENODEV;       /* Don't resuscitate */
2796                 }
2797                 usb_unlock_device(udev);
2798
2799                 if (status == 0) {
2800                         clear_bit(port1, hub->change_bits);
2801                         return;
2802                 }
2803         }
2804
2805         /* Disconnect any existing devices under this port */
2806         if (udev)
2807                 usb_disconnect(&hdev->children[port1-1]);
2808         clear_bit(port1, hub->change_bits);
2809
2810         if (portchange & (USB_PORT_STAT_C_CONNECTION |
2811                                 USB_PORT_STAT_C_ENABLE)) {
2812                 status = hub_port_debounce(hub, port1);
2813                 if (status < 0) {
2814                         if (printk_ratelimit())
2815                                 dev_err(hub_dev, "connect-debounce failed, "
2816                                                 "port %d disabled\n", port1);
2817                         portstatus &= ~USB_PORT_STAT_CONNECTION;
2818                 } else {
2819                         portstatus = status;
2820                 }
2821         }
2822
2823         /* Return now if debouncing failed or nothing is connected */
2824         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2825
2826                 /* maybe switch power back on (e.g. root hub was reset) */
2827                 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2828                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2829                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2830
2831                 if (portstatus & USB_PORT_STAT_ENABLE)
2832                         goto done;
2833                 return;
2834         }
2835
2836         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2837
2838                 /* reallocate for each attempt, since references
2839                  * to the previous one can escape in various ways
2840                  */
2841                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2842                 if (!udev) {
2843                         dev_err (hub_dev,
2844                                 "couldn't allocate port %d usb_device\n",
2845                                 port1);
2846                         goto done;
2847                 }
2848
2849                 usb_set_device_state(udev, USB_STATE_POWERED);
2850                 udev->speed = USB_SPEED_UNKNOWN;
2851                 udev->bus_mA = hub->mA_per_port;
2852                 udev->level = hdev->level + 1;
2853                 udev->wusb = hub_is_wusb(hub);
2854
2855                 /* set the address */
2856                 choose_address(udev);
2857                 if (udev->devnum <= 0) {
2858                         status = -ENOTCONN;     /* Don't retry */
2859                         goto loop;
2860                 }
2861
2862                 /* reset and get descriptor */
2863                 status = hub_port_init(hub, udev, port1, i);
2864                 if (status < 0)
2865                         goto loop;
2866
2867                 /* consecutive bus-powered hubs aren't reliable; they can
2868                  * violate the voltage drop budget.  if the new child has
2869                  * a "powered" LED, users should notice we didn't enable it
2870                  * (without reading syslog), even without per-port LEDs
2871                  * on the parent.
2872                  */
2873                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2874                                 && udev->bus_mA <= 100) {
2875                         u16     devstat;
2876
2877                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2878                                         &devstat);
2879                         if (status < 2) {
2880                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2881                                 goto loop_disable;
2882                         }
2883                         le16_to_cpus(&devstat);
2884                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2885                                 dev_err(&udev->dev,
2886                                         "can't connect bus-powered hub "
2887                                         "to this port\n");
2888                                 if (hub->has_indicators) {
2889                                         hub->indicator[port1-1] =
2890                                                 INDICATOR_AMBER_BLINK;
2891                                         schedule_delayed_work (&hub->leds, 0);
2892                                 }
2893                                 status = -ENOTCONN;     /* Don't retry */
2894                                 goto loop_disable;
2895                         }
2896                 }
2897  
2898                 /* check for devices running slower than they could */
2899                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2900                                 && udev->speed == USB_SPEED_FULL
2901                                 && highspeed_hubs != 0)
2902                         check_highspeed (hub, udev, port1);
2903
2904                 /* Store the parent's children[] pointer.  At this point
2905                  * udev becomes globally accessible, although presumably
2906                  * no one will look at it until hdev is unlocked.
2907                  */
2908                 status = 0;
2909
2910                 /* We mustn't add new devices if the parent hub has
2911                  * been disconnected; we would race with the
2912                  * recursively_mark_NOTATTACHED() routine.
2913                  */
2914                 spin_lock_irq(&device_state_lock);
2915                 if (hdev->state == USB_STATE_NOTATTACHED)
2916                         status = -ENOTCONN;
2917                 else
2918                         hdev->children[port1-1] = udev;
2919                 spin_unlock_irq(&device_state_lock);
2920
2921                 /* Run it through the hoops (find a driver, etc) */
2922                 if (!status) {
2923                         status = usb_new_device(udev);
2924                         if (status) {
2925                                 spin_lock_irq(&device_state_lock);
2926                                 hdev->children[port1-1] = NULL;
2927                                 spin_unlock_irq(&device_state_lock);
2928                         }
2929                 }
2930
2931                 if (status)
2932                         goto loop_disable;
2933
2934                 status = hub_power_remaining(hub);
2935                 if (status)
2936                         dev_dbg(hub_dev, "%dmA power budget left\n", status);
2937
2938                 return;
2939
2940 loop_disable:
2941                 hub_port_disable(hub, port1, 1);
2942 loop:
2943                 usb_ep0_reinit(udev);
2944                 release_address(udev);
2945                 usb_put_dev(udev);
2946                 if ((status == -ENOTCONN) || (status == -ENOTSUPP))
2947                         break;
2948         }
2949         if (hub->hdev->parent ||
2950                         !hcd->driver->port_handed_over ||
2951                         !(hcd->driver->port_handed_over)(hcd, port1))
2952                 dev_err(hub_dev, "unable to enumerate USB device on port %d\n",
2953                                 port1);
2954  
2955 done:
2956         hub_port_disable(hub, port1, 1);
2957         if (hcd->driver->relinquish_port && !hub->hdev->parent)
2958                 hcd->driver->relinquish_port(hcd, port1);
2959 }
2960
2961 static void hub_events(void)
2962 {
2963         struct list_head *tmp;
2964         struct usb_device *hdev;
2965         struct usb_interface *intf;
2966         struct usb_hub *hub;
2967         struct device *hub_dev;
2968         u16 hubstatus;
2969         u16 hubchange;
2970         u16 portstatus;
2971         u16 portchange;
2972         int i, ret;
2973         int connect_change;
2974
2975         /*
2976          *  We restart the list every time to avoid a deadlock with
2977          * deleting hubs downstream from this one. This should be
2978          * safe since we delete the hub from the event list.
2979          * Not the most efficient, but avoids deadlocks.
2980          */
2981         while (1) {
2982
2983                 /* Grab the first entry at the beginning of the list */
2984                 spin_lock_irq(&hub_event_lock);
2985                 if (list_empty(&hub_event_list)) {
2986                         spin_unlock_irq(&hub_event_lock);
2987                         break;
2988                 }
2989
2990                 tmp = hub_event_list.next;
2991                 list_del_init(tmp);
2992
2993                 hub = list_entry(tmp, struct usb_hub, event_list);
2994                 kref_get(&hub->kref);
2995                 spin_unlock_irq(&hub_event_lock);
2996
2997                 hdev = hub->hdev;
2998                 hub_dev = hub->intfdev;
2999                 intf = to_usb_interface(hub_dev);
3000                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
3001                                 hdev->state, hub->descriptor
3002                                         ? hub->descriptor->bNbrPorts
3003                                         : 0,
3004                                 /* NOTE: expects max 15 ports... */
3005                                 (u16) hub->change_bits[0],
3006                                 (u16) hub->event_bits[0]);
3007
3008                 /* Lock the device, then check to see if we were
3009                  * disconnected while waiting for the lock to succeed. */
3010                 usb_lock_device(hdev);
3011                 if (unlikely(hub->disconnected))
3012                         goto loop;
3013
3014                 /* If the hub has died, clean up after it */
3015                 if (hdev->state == USB_STATE_NOTATTACHED) {
3016                         hub->error = -ENODEV;
3017                         hub_quiesce(hub, HUB_DISCONNECT);
3018                         goto loop;
3019                 }
3020
3021                 /* Autoresume */
3022                 ret = usb_autopm_get_interface(intf);
3023                 if (ret) {
3024                         dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
3025                         goto loop;
3026                 }
3027
3028                 /* If this is an inactive hub, do nothing */
3029                 if (hub->quiescing)
3030                         goto loop_autopm;
3031
3032                 if (hub->error) {
3033                         dev_dbg (hub_dev, "resetting for error %d\n",
3034                                 hub->error);
3035
3036                         ret = usb_reset_device(hdev);
3037                         if (ret) {
3038                                 dev_dbg (hub_dev,
3039                                         "error resetting hub: %d\n", ret);
3040                                 goto loop_autopm;
3041                         }
3042
3043                         hub->nerrors = 0;
3044                         hub->error = 0;
3045                 }
3046
3047                 /* deal with port status changes */
3048                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
3049                         if (test_bit(i, hub->busy_bits))
3050                                 continue;
3051                         connect_change = test_bit(i, hub->change_bits);
3052                         if (!test_and_clear_bit(i, hub->event_bits) &&
3053                                         !connect_change)
3054                                 continue;
3055
3056                         ret = hub_port_status(hub, i,
3057                                         &portstatus, &portchange);
3058                         if (ret < 0)
3059                                 continue;
3060
3061                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
3062                                 clear_port_feature(hdev, i,
3063                                         USB_PORT_FEAT_C_CONNECTION);
3064                                 connect_change = 1;
3065                         }
3066
3067                         if (portchange & USB_PORT_STAT_C_ENABLE) {
3068                                 if (!connect_change)
3069                                         dev_dbg (hub_dev,
3070                                                 "port %d enable change, "
3071                                                 "status %08x\n",
3072                                                 i, portstatus);
3073                                 clear_port_feature(hdev, i,
3074                                         USB_PORT_FEAT_C_ENABLE);
3075
3076                                 /*
3077                                  * EM interference sometimes causes badly
3078                                  * shielded USB devices to be shutdown by
3079                                  * the hub, this hack enables them again.
3080                                  * Works at least with mouse driver. 
3081                                  */
3082                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
3083                                     && !connect_change
3084                                     && hdev->children[i-1]) {
3085                                         dev_err (hub_dev,
3086                                             "port %i "
3087                                             "disabled by hub (EMI?), "
3088                                             "re-enabling...\n",
3089                                                 i);
3090                                         connect_change = 1;
3091                                 }
3092                         }
3093
3094                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
3095                                 struct usb_device *udev;
3096
3097                                 clear_port_feature(hdev, i,
3098                                         USB_PORT_FEAT_C_SUSPEND);
3099                                 udev = hdev->children[i-1];
3100                                 if (udev) {
3101                                         usb_lock_device(udev);
3102                                         ret = remote_wakeup(hdev->
3103                                                         children[i-1]);
3104                                         usb_unlock_device(udev);
3105                                         if (ret < 0)
3106                                                 connect_change = 1;
3107                                 } else {
3108                                         ret = -ENODEV;
3109                                         hub_port_disable(hub, i, 1);
3110                                 }
3111                                 dev_dbg (hub_dev,
3112                                         "resume on port %d, status %d\n",
3113                                         i, ret);
3114                         }
3115                         
3116                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
3117                                 dev_err (hub_dev,
3118                                         "over-current change on port %d\n",
3119                                         i);
3120                                 clear_port_feature(hdev, i,
3121                                         USB_PORT_FEAT_C_OVER_CURRENT);
3122                                 hub_power_on(hub, true);
3123                         }
3124
3125                         if (portchange & USB_PORT_STAT_C_RESET) {
3126                                 dev_dbg (hub_dev,
3127                                         "reset change on port %d\n",
3128                                         i);
3129                                 clear_port_feature(hdev, i,
3130                                         USB_PORT_FEAT_C_RESET);
3131                         }
3132
3133                         if (connect_change)
3134                                 hub_port_connect_change(hub, i,
3135                                                 portstatus, portchange);
3136                 } /* end for i */
3137
3138                 /* deal with hub status changes */
3139                 if (test_and_clear_bit(0, hub->event_bits) == 0)
3140                         ;       /* do nothing */
3141                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
3142                         dev_err (hub_dev, "get_hub_status failed\n");
3143                 else {
3144                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
3145                                 dev_dbg (hub_dev, "power change\n");
3146                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
3147                                 if (hubstatus & HUB_STATUS_LOCAL_POWER)
3148                                         /* FIXME: Is this always true? */
3149                                         hub->limited_power = 1;
3150                                 else
3151                                         hub->limited_power = 0;
3152                         }
3153                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
3154                                 dev_dbg (hub_dev, "overcurrent change\n");
3155                                 msleep(500);    /* Cool down */
3156                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
3157                                 hub_power_on(hub, true);
3158                         }
3159                 }
3160
3161 loop_autopm:
3162                 /* Allow autosuspend if we're not going to run again */
3163                 if (list_empty(&hub->event_list))
3164                         usb_autopm_enable(intf);
3165 loop:
3166                 usb_unlock_device(hdev);
3167                 kref_put(&hub->kref, hub_release);
3168
3169         } /* end while (1) */
3170 }
3171
3172 static int hub_thread(void *__unused)
3173 {
3174         /* khubd needs to be freezable to avoid intefering with USB-PERSIST
3175          * port handover.  Otherwise it might see that a full-speed device
3176          * was gone before the EHCI controller had handed its port over to
3177          * the companion full-speed controller.
3178          */
3179         set_freezable();
3180
3181         do {
3182                 hub_events();
3183                 wait_event_freezable(khubd_wait,
3184                                 !list_empty(&hub_event_list) ||
3185                                 kthread_should_stop());
3186         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
3187
3188         pr_debug("%s: khubd exiting\n", usbcore_name);
3189         return 0;
3190 }
3191
3192 static struct usb_device_id hub_id_table [] = {
3193     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
3194       .bDeviceClass = USB_CLASS_HUB},
3195     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
3196       .bInterfaceClass = USB_CLASS_HUB},
3197     { }                                         /* Terminating entry */
3198 };
3199
3200 MODULE_DEVICE_TABLE (usb, hub_id_table);
3201
3202 static struct usb_driver hub_driver = {
3203         .name =         "hub",
3204         .probe =        hub_probe,
3205         .disconnect =   hub_disconnect,
3206         .suspend =      hub_suspend,
3207         .resume =       hub_resume,
3208         .reset_resume = hub_reset_resume,
3209         .pre_reset =    hub_pre_reset,
3210         .post_reset =   hub_post_reset,
3211         .ioctl =        hub_ioctl,
3212         .id_table =     hub_id_table,
3213         .supports_autosuspend = 1,
3214 };
3215
3216 int usb_hub_init(void)
3217 {
3218         if (usb_register(&hub_driver) < 0) {
3219                 printk(KERN_ERR "%s: can't register hub driver\n",
3220                         usbcore_name);
3221                 return -1;
3222         }
3223
3224         khubd_task = kthread_run(hub_thread, NULL, "khubd");
3225         if (!IS_ERR(khubd_task))
3226                 return 0;
3227
3228         /* Fall through if kernel_thread failed */
3229         usb_deregister(&hub_driver);
3230         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
3231
3232         return -1;
3233 }
3234
3235 void usb_hub_cleanup(void)
3236 {
3237         kthread_stop(khubd_task);
3238
3239         /*
3240          * Hub resources are freed for us by usb_deregister. It calls
3241          * usb_driver_purge on every device which in turn calls that
3242          * devices disconnect function if it is using this driver.
3243          * The hub_disconnect function takes care of releasing the
3244          * individual hub resources. -greg
3245          */
3246         usb_deregister(&hub_driver);
3247 } /* usb_hub_cleanup() */
3248
3249 static int descriptors_changed(struct usb_device *udev,
3250                 struct usb_device_descriptor *old_device_descriptor)
3251 {
3252         int             changed = 0;
3253         unsigned        index;
3254         unsigned        serial_len = 0;
3255         unsigned        len;
3256         unsigned        old_length;
3257         int             length;
3258         char            *buf;
3259
3260         if (memcmp(&udev->descriptor, old_device_descriptor,
3261                         sizeof(*old_device_descriptor)) != 0)
3262                 return 1;
3263
3264         /* Since the idVendor, idProduct, and bcdDevice values in the
3265          * device descriptor haven't changed, we will assume the
3266          * Manufacturer and Product strings haven't changed either.
3267          * But the SerialNumber string could be different (e.g., a
3268          * different flash card of the same brand).
3269          */
3270         if (udev->serial)
3271                 serial_len = strlen(udev->serial) + 1;
3272
3273         len = serial_len;
3274         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
3275                 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
3276                 len = max(len, old_length);
3277         }
3278
3279         buf = kmalloc(len, GFP_NOIO);
3280         if (buf == NULL) {
3281                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
3282                 /* assume the worst */
3283                 return 1;
3284         }
3285         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
3286                 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
3287                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
3288                                 old_length);
3289                 if (length != old_length) {
3290                         dev_dbg(&udev->dev, "config index %d, error %d\n",
3291                                         index, length);
3292                         changed = 1;
3293                         break;
3294                 }
3295                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
3296                                 != 0) {
3297                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
3298                                 index,
3299                                 ((struct usb_config_descriptor *) buf)->
3300                                         bConfigurationValue);
3301                         changed = 1;
3302                         break;
3303                 }
3304         }
3305
3306         if (!changed && serial_len) {
3307                 length = usb_string(udev, udev->descriptor.iSerialNumber,
3308                                 buf, serial_len);
3309                 if (length + 1 != serial_len) {
3310                         dev_dbg(&udev->dev, "serial string error %d\n",
3311                                         length);
3312                         changed = 1;
3313                 } else if (memcmp(buf, udev->serial, length) != 0) {
3314                         dev_dbg(&udev->dev, "serial string changed\n");
3315                         changed = 1;
3316                 }
3317         }
3318
3319         kfree(buf);
3320         return changed;
3321 }
3322
3323 /**
3324  * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
3325  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3326  *
3327  * WARNING - don't use this routine to reset a composite device
3328  * (one with multiple interfaces owned by separate drivers)!
3329  * Use usb_reset_device() instead.
3330  *
3331  * Do a port reset, reassign the device's address, and establish its
3332  * former operating configuration.  If the reset fails, or the device's
3333  * descriptors change from their values before the reset, or the original
3334  * configuration and altsettings cannot be restored, a flag will be set
3335  * telling khubd to pretend the device has been disconnected and then
3336  * re-connected.  All drivers will be unbound, and the device will be
3337  * re-enumerated and probed all over again.
3338  *
3339  * Returns 0 if the reset succeeded, -ENODEV if the device has been
3340  * flagged for logical disconnection, or some other negative error code
3341  * if the reset wasn't even attempted.
3342  *
3343  * The caller must own the device lock.  For example, it's safe to use
3344  * this from a driver probe() routine after downloading new firmware.
3345  * For calls that might not occur during probe(), drivers should lock
3346  * the device using usb_lock_device_for_reset().
3347  *
3348  * Locking exception: This routine may also be called from within an
3349  * autoresume handler.  Such usage won't conflict with other tasks
3350  * holding the device lock because these tasks should always call
3351  * usb_autopm_resume_device(), thereby preventing any unwanted autoresume.
3352  */
3353 static int usb_reset_and_verify_device(struct usb_device *udev)
3354 {
3355         struct usb_device               *parent_hdev = udev->parent;
3356         struct usb_hub                  *parent_hub;
3357         struct usb_device_descriptor    descriptor = udev->descriptor;
3358         int                             i, ret = 0;
3359         int                             port1 = udev->portnum;
3360
3361         if (udev->state == USB_STATE_NOTATTACHED ||
3362                         udev->state == USB_STATE_SUSPENDED) {
3363                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3364                                 udev->state);
3365                 return -EINVAL;
3366         }
3367
3368         if (!parent_hdev) {
3369                 /* this requires hcd-specific logic; see OHCI hc_restart() */
3370                 dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
3371                 return -EISDIR;
3372         }
3373         parent_hub = hdev_to_hub(parent_hdev);
3374
3375         set_bit(port1, parent_hub->busy_bits);
3376         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
3377
3378                 /* ep0 maxpacket size may change; let the HCD know about it.
3379                  * Other endpoints will be handled by re-enumeration. */
3380                 usb_ep0_reinit(udev);
3381                 ret = hub_port_init(parent_hub, udev, port1, i);
3382                 if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
3383                         break;
3384         }
3385         clear_bit(port1, parent_hub->busy_bits);
3386
3387         if (ret < 0)
3388                 goto re_enumerate;
3389  
3390         /* Device might have changed firmware (DFU or similar) */
3391         if (descriptors_changed(udev, &descriptor)) {
3392                 dev_info(&udev->dev, "device firmware changed\n");
3393                 udev->descriptor = descriptor;  /* for disconnect() calls */
3394                 goto re_enumerate;
3395         }
3396   
3397         if (!udev->actconfig)
3398                 goto done;
3399
3400         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3401                         USB_REQ_SET_CONFIGURATION, 0,
3402                         udev->actconfig->desc.bConfigurationValue, 0,
3403                         NULL, 0, USB_CTRL_SET_TIMEOUT);
3404         if (ret < 0) {
3405                 dev_err(&udev->dev,
3406                         "can't restore configuration #%d (error=%d)\n",
3407                         udev->actconfig->desc.bConfigurationValue, ret);
3408                 goto re_enumerate;
3409         }
3410         usb_set_device_state(udev, USB_STATE_CONFIGURED);
3411
3412         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3413                 struct usb_interface *intf = udev->actconfig->interface[i];
3414                 struct usb_interface_descriptor *desc;
3415
3416                 /* set_interface resets host side toggle even
3417                  * for altsetting zero.  the interface may have no driver.
3418                  */
3419                 desc = &intf->cur_altsetting->desc;
3420                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3421                         desc->bAlternateSetting);
3422                 if (ret < 0) {
3423                         dev_err(&udev->dev, "failed to restore interface %d "
3424                                 "altsetting %d (error=%d)\n",
3425                                 desc->bInterfaceNumber,
3426                                 desc->bAlternateSetting,
3427                                 ret);
3428                         goto re_enumerate;
3429                 }
3430         }
3431
3432 done:
3433         return 0;
3434  
3435 re_enumerate:
3436         hub_port_logical_disconnect(parent_hub, port1);
3437         return -ENODEV;
3438 }
3439
3440 /**
3441  * usb_reset_device - warn interface drivers and perform a USB port reset
3442  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
3443  *
3444  * Warns all drivers bound to registered interfaces (using their pre_reset
3445  * method), performs the port reset, and then lets the drivers know that
3446  * the reset is over (using their post_reset method).
3447  *
3448  * Return value is the same as for usb_reset_and_verify_device().
3449  *
3450  * The caller must own the device lock.  For example, it's safe to use
3451  * this from a driver probe() routine after downloading new firmware.
3452  * For calls that might not occur during probe(), drivers should lock
3453  * the device using usb_lock_device_for_reset().
3454  *
3455  * If an interface is currently being probed or disconnected, we assume
3456  * its driver knows how to handle resets.  For all other interfaces,
3457  * if the driver doesn't have pre_reset and post_reset methods then
3458  * we attempt to unbind it and rebind afterward.
3459  */
3460 int usb_reset_device(struct usb_device *udev)
3461 {
3462         int ret;
3463         int i;
3464         struct usb_host_config *config = udev->actconfig;
3465
3466         if (udev->state == USB_STATE_NOTATTACHED ||
3467                         udev->state == USB_STATE_SUSPENDED) {
3468                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3469                                 udev->state);
3470                 return -EINVAL;
3471         }
3472
3473         /* Prevent autosuspend during the reset */
3474         usb_autoresume_device(udev);
3475
3476         if (config) {
3477                 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
3478                         struct usb_interface *cintf = config->interface[i];
3479                         struct usb_driver *drv;
3480                         int unbind = 0;
3481
3482                         if (cintf->dev.driver) {
3483                                 drv = to_usb_driver(cintf->dev.driver);
3484                                 if (drv->pre_reset && drv->post_reset)
3485                                         unbind = (drv->pre_reset)(cintf);
3486                                 else if (cintf->condition ==
3487                                                 USB_INTERFACE_BOUND)
3488                                         unbind = 1;
3489                                 if (unbind)
3490                                         usb_forced_unbind_intf(cintf);
3491                         }
3492                 }
3493         }
3494
3495         ret = usb_reset_and_verify_device(udev);
3496
3497         if (config) {
3498                 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
3499                         struct usb_interface *cintf = config->interface[i];
3500                         struct usb_driver *drv;
3501                         int rebind = cintf->needs_binding;
3502
3503                         if (!rebind && cintf->dev.driver) {
3504                                 drv = to_usb_driver(cintf->dev.driver);
3505                                 if (drv->post_reset)
3506                                         rebind = (drv->post_reset)(cintf);
3507                                 else if (cintf->condition ==
3508                                                 USB_INTERFACE_BOUND)
3509                                         rebind = 1;
3510                         }
3511                         if (ret == 0 && rebind)
3512                                 usb_rebind_intf(cintf);
3513                 }
3514         }
3515
3516         usb_autosuspend_device(udev);
3517         return ret;
3518 }
3519 EXPORT_SYMBOL_GPL(usb_reset_device);