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