Merge branch 'usb-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh...
[pandora-kernel.git] / 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/usb/hcd.h>
23 #include <linux/usb/quirks.h>
24 #include <linux/kthread.h>
25 #include <linux/mutex.h>
26 #include <linux/freezer.h>
27
28 #include <asm/uaccess.h>
29 #include <asm/byteorder.h>
30
31 #include "usb.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         union {
49                 struct usb_hub_status   hub;
50                 struct usb_port_status  port;
51         }                       *status;        /* buffer for status reports */
52         struct mutex            status_mutex;   /* for the status buffer */
53
54         int                     error;          /* last reported error */
55         int                     nerrors;        /* track consecutive errors */
56
57         struct list_head        event_list;     /* hubs w/data or errs ready */
58         unsigned long           event_bits[1];  /* status change bitmask */
59         unsigned long           change_bits[1]; /* ports with logical connect
60                                                         status change */
61         unsigned long           busy_bits[1];   /* ports being reset or
62                                                         resumed */
63         unsigned long           removed_bits[1]; /* ports with a "removed"
64                                                         device present */
65 #if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
66 #error event_bits[] is too short!
67 #endif
68
69         struct usb_hub_descriptor *descriptor;  /* class descriptor */
70         struct usb_tt           tt;             /* Transaction Translator */
71
72         unsigned                mA_per_port;    /* current for each child */
73
74         unsigned                limited_power:1;
75         unsigned                quiescing:1;
76         unsigned                disconnected:1;
77
78         unsigned                has_indicators:1;
79         u8                      indicator[USB_MAXCHILDREN];
80         struct delayed_work     leds;
81         struct delayed_work     init_work;
82         void                    **port_owners;
83 };
84
85 static inline int hub_is_superspeed(struct usb_device *hdev)
86 {
87         return (hdev->descriptor.bDeviceProtocol == 3);
88 }
89
90 /* Protect struct usb_device->state and ->children members
91  * Note: Both are also protected by ->dev.sem, except that ->state can
92  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
93 static DEFINE_SPINLOCK(device_state_lock);
94
95 /* khubd's worklist and its lock */
96 static DEFINE_SPINLOCK(hub_event_lock);
97 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
98
99 /* Wakes up khubd */
100 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
101
102 static struct task_struct *khubd_task;
103
104 /* cycle leds on hubs that aren't blinking for attention */
105 static int blinkenlights = 0;
106 module_param (blinkenlights, bool, S_IRUGO);
107 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
108
109 /*
110  * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
111  * 10 seconds to send reply for the initial 64-byte descriptor request.
112  */
113 /* define initial 64-byte descriptor request timeout in milliseconds */
114 static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
115 module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
116 MODULE_PARM_DESC(initial_descriptor_timeout,
117                 "initial 64-byte descriptor request timeout in milliseconds "
118                 "(default 5000 - 5.0 seconds)");
119
120 /*
121  * As of 2.6.10 we introduce a new USB device initialization scheme which
122  * closely resembles the way Windows works.  Hopefully it will be compatible
123  * with a wider range of devices than the old scheme.  However some previously
124  * working devices may start giving rise to "device not accepting address"
125  * errors; if that happens the user can try the old scheme by adjusting the
126  * following module parameters.
127  *
128  * For maximum flexibility there are two boolean parameters to control the
129  * hub driver's behavior.  On the first initialization attempt, if the
130  * "old_scheme_first" parameter is set then the old scheme will be used,
131  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
132  * is set, then the driver will make another attempt, using the other scheme.
133  */
134 static int old_scheme_first = 0;
135 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
136 MODULE_PARM_DESC(old_scheme_first,
137                  "start with the old device initialization scheme");
138
139 static int use_both_schemes = 1;
140 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
141 MODULE_PARM_DESC(use_both_schemes,
142                 "try the other device initialization scheme if the "
143                 "first one fails");
144
145 /* Mutual exclusion for EHCI CF initialization.  This interferes with
146  * port reset on some companion controllers.
147  */
148 DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
149 EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
150
151 #define HUB_DEBOUNCE_TIMEOUT    1500
152 #define HUB_DEBOUNCE_STEP         25
153 #define HUB_DEBOUNCE_STABLE      100
154
155
156 static int usb_reset_and_verify_device(struct usb_device *udev);
157
158 static inline char *portspeed(struct usb_hub *hub, int portstatus)
159 {
160         if (hub_is_superspeed(hub->hdev))
161                 return "5.0 Gb/s";
162         if (portstatus & USB_PORT_STAT_HIGH_SPEED)
163                 return "480 Mb/s";
164         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
165                 return "1.5 Mb/s";
166         else
167                 return "12 Mb/s";
168 }
169
170 /* Note that hdev or one of its children must be locked! */
171 static struct usb_hub *hdev_to_hub(struct usb_device *hdev)
172 {
173         if (!hdev || !hdev->actconfig)
174                 return NULL;
175         return usb_get_intfdata(hdev->actconfig->interface[0]);
176 }
177
178 /* USB 2.0 spec Section 11.24.4.5 */
179 static int get_hub_descriptor(struct usb_device *hdev, void *data)
180 {
181         int i, ret, size;
182         unsigned dtype;
183
184         if (hub_is_superspeed(hdev)) {
185                 dtype = USB_DT_SS_HUB;
186                 size = USB_DT_SS_HUB_SIZE;
187         } else {
188                 dtype = USB_DT_HUB;
189                 size = sizeof(struct usb_hub_descriptor);
190         }
191
192         for (i = 0; i < 3; i++) {
193                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
194                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
195                         dtype << 8, 0, data, size,
196                         USB_CTRL_GET_TIMEOUT);
197                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
198                         return ret;
199         }
200         return -EINVAL;
201 }
202
203 /*
204  * USB 2.0 spec Section 11.24.2.1
205  */
206 static int clear_hub_feature(struct usb_device *hdev, int feature)
207 {
208         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
209                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
210 }
211
212 /*
213  * USB 2.0 spec Section 11.24.2.2
214  */
215 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
216 {
217         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
218                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
219                 NULL, 0, 1000);
220 }
221
222 /*
223  * USB 2.0 spec Section 11.24.2.13
224  */
225 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
226 {
227         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
228                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
229                 NULL, 0, 1000);
230 }
231
232 /*
233  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
234  * for info about using port indicators
235  */
236 static void set_port_led(
237         struct usb_hub *hub,
238         int port1,
239         int selector
240 )
241 {
242         int status = set_port_feature(hub->hdev, (selector << 8) | port1,
243                         USB_PORT_FEAT_INDICATOR);
244         if (status < 0)
245                 dev_dbg (hub->intfdev,
246                         "port %d indicator %s status %d\n",
247                         port1,
248                         ({ char *s; switch (selector) {
249                         case HUB_LED_AMBER: s = "amber"; break;
250                         case HUB_LED_GREEN: s = "green"; break;
251                         case HUB_LED_OFF: s = "off"; break;
252                         case HUB_LED_AUTO: s = "auto"; break;
253                         default: s = "??"; break;
254                         }; s; }),
255                         status);
256 }
257
258 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
259
260 static void led_work (struct work_struct *work)
261 {
262         struct usb_hub          *hub =
263                 container_of(work, struct usb_hub, leds.work);
264         struct usb_device       *hdev = hub->hdev;
265         unsigned                i;
266         unsigned                changed = 0;
267         int                     cursor = -1;
268
269         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
270                 return;
271
272         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
273                 unsigned        selector, mode;
274
275                 /* 30%-50% duty cycle */
276
277                 switch (hub->indicator[i]) {
278                 /* cycle marker */
279                 case INDICATOR_CYCLE:
280                         cursor = i;
281                         selector = HUB_LED_AUTO;
282                         mode = INDICATOR_AUTO;
283                         break;
284                 /* blinking green = sw attention */
285                 case INDICATOR_GREEN_BLINK:
286                         selector = HUB_LED_GREEN;
287                         mode = INDICATOR_GREEN_BLINK_OFF;
288                         break;
289                 case INDICATOR_GREEN_BLINK_OFF:
290                         selector = HUB_LED_OFF;
291                         mode = INDICATOR_GREEN_BLINK;
292                         break;
293                 /* blinking amber = hw attention */
294                 case INDICATOR_AMBER_BLINK:
295                         selector = HUB_LED_AMBER;
296                         mode = INDICATOR_AMBER_BLINK_OFF;
297                         break;
298                 case INDICATOR_AMBER_BLINK_OFF:
299                         selector = HUB_LED_OFF;
300                         mode = INDICATOR_AMBER_BLINK;
301                         break;
302                 /* blink green/amber = reserved */
303                 case INDICATOR_ALT_BLINK:
304                         selector = HUB_LED_GREEN;
305                         mode = INDICATOR_ALT_BLINK_OFF;
306                         break;
307                 case INDICATOR_ALT_BLINK_OFF:
308                         selector = HUB_LED_AMBER;
309                         mode = INDICATOR_ALT_BLINK;
310                         break;
311                 default:
312                         continue;
313                 }
314                 if (selector != HUB_LED_AUTO)
315                         changed = 1;
316                 set_port_led(hub, i + 1, selector);
317                 hub->indicator[i] = mode;
318         }
319         if (!changed && blinkenlights) {
320                 cursor++;
321                 cursor %= hub->descriptor->bNbrPorts;
322                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
323                 hub->indicator[cursor] = INDICATOR_CYCLE;
324                 changed++;
325         }
326         if (changed)
327                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
328 }
329
330 /* use a short timeout for hub/port status fetches */
331 #define USB_STS_TIMEOUT         1000
332 #define USB_STS_RETRIES         5
333
334 /*
335  * USB 2.0 spec Section 11.24.2.6
336  */
337 static int get_hub_status(struct usb_device *hdev,
338                 struct usb_hub_status *data)
339 {
340         int i, status = -ETIMEDOUT;
341
342         for (i = 0; i < USB_STS_RETRIES &&
343                         (status == -ETIMEDOUT || status == -EPIPE); i++) {
344                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
345                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
346                         data, sizeof(*data), USB_STS_TIMEOUT);
347         }
348         return status;
349 }
350
351 /*
352  * USB 2.0 spec Section 11.24.2.7
353  */
354 static int get_port_status(struct usb_device *hdev, int port1,
355                 struct usb_port_status *data)
356 {
357         int i, status = -ETIMEDOUT;
358
359         for (i = 0; i < USB_STS_RETRIES &&
360                         (status == -ETIMEDOUT || status == -EPIPE); i++) {
361                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
362                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
363                         data, sizeof(*data), USB_STS_TIMEOUT);
364         }
365         return status;
366 }
367
368 static int hub_port_status(struct usb_hub *hub, int port1,
369                 u16 *status, u16 *change)
370 {
371         int ret;
372
373         mutex_lock(&hub->status_mutex);
374         ret = get_port_status(hub->hdev, port1, &hub->status->port);
375         if (ret < 4) {
376                 dev_err(hub->intfdev,
377                         "%s failed (err = %d)\n", __func__, ret);
378                 if (ret >= 0)
379                         ret = -EIO;
380         } else {
381                 *status = le16_to_cpu(hub->status->port.wPortStatus);
382                 *change = le16_to_cpu(hub->status->port.wPortChange);
383
384                 ret = 0;
385         }
386         mutex_unlock(&hub->status_mutex);
387         return ret;
388 }
389
390 static void kick_khubd(struct usb_hub *hub)
391 {
392         unsigned long   flags;
393
394         spin_lock_irqsave(&hub_event_lock, flags);
395         if (!hub->disconnected && list_empty(&hub->event_list)) {
396                 list_add_tail(&hub->event_list, &hub_event_list);
397
398                 /* Suppress autosuspend until khubd runs */
399                 usb_autopm_get_interface_no_resume(
400                                 to_usb_interface(hub->intfdev));
401                 wake_up(&khubd_wait);
402         }
403         spin_unlock_irqrestore(&hub_event_lock, flags);
404 }
405
406 void usb_kick_khubd(struct usb_device *hdev)
407 {
408         struct usb_hub *hub = hdev_to_hub(hdev);
409
410         if (hub)
411                 kick_khubd(hub);
412 }
413
414
415 /* completion function, fires on port status changes and various faults */
416 static void hub_irq(struct urb *urb)
417 {
418         struct usb_hub *hub = urb->context;
419         int status = urb->status;
420         unsigned i;
421         unsigned long bits;
422
423         switch (status) {
424         case -ENOENT:           /* synchronous unlink */
425         case -ECONNRESET:       /* async unlink */
426         case -ESHUTDOWN:        /* hardware going away */
427                 return;
428
429         default:                /* presumably an error */
430                 /* Cause a hub reset after 10 consecutive errors */
431                 dev_dbg (hub->intfdev, "transfer --> %d\n", status);
432                 if ((++hub->nerrors < 10) || hub->error)
433                         goto resubmit;
434                 hub->error = status;
435                 /* FALL THROUGH */
436
437         /* let khubd handle things */
438         case 0:                 /* we got data:  port status changed */
439                 bits = 0;
440                 for (i = 0; i < urb->actual_length; ++i)
441                         bits |= ((unsigned long) ((*hub->buffer)[i]))
442                                         << (i*8);
443                 hub->event_bits[0] = bits;
444                 break;
445         }
446
447         hub->nerrors = 0;
448
449         /* Something happened, let khubd figure it out */
450         kick_khubd(hub);
451
452 resubmit:
453         if (hub->quiescing)
454                 return;
455
456         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
457                         && status != -ENODEV && status != -EPERM)
458                 dev_err (hub->intfdev, "resubmit --> %d\n", status);
459 }
460
461 /* USB 2.0 spec Section 11.24.2.3 */
462 static inline int
463 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
464 {
465         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
466                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
467                                tt, NULL, 0, 1000);
468 }
469
470 /*
471  * enumeration blocks khubd for a long time. we use keventd instead, since
472  * long blocking there is the exception, not the rule.  accordingly, HCDs
473  * talking to TTs must queue control transfers (not just bulk and iso), so
474  * both can talk to the same hub concurrently.
475  */
476 static void hub_tt_work(struct work_struct *work)
477 {
478         struct usb_hub          *hub =
479                 container_of(work, struct usb_hub, tt.clear_work);
480         unsigned long           flags;
481         int                     limit = 100;
482
483         spin_lock_irqsave (&hub->tt.lock, flags);
484         while (--limit && !list_empty (&hub->tt.clear_list)) {
485                 struct list_head        *next;
486                 struct usb_tt_clear     *clear;
487                 struct usb_device       *hdev = hub->hdev;
488                 const struct hc_driver  *drv;
489                 int                     status;
490
491                 next = hub->tt.clear_list.next;
492                 clear = list_entry (next, struct usb_tt_clear, clear_list);
493                 list_del (&clear->clear_list);
494
495                 /* drop lock so HCD can concurrently report other TT errors */
496                 spin_unlock_irqrestore (&hub->tt.lock, flags);
497                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
498                 if (status)
499                         dev_err (&hdev->dev,
500                                 "clear tt %d (%04x) error %d\n",
501                                 clear->tt, clear->devinfo, status);
502
503                 /* Tell the HCD, even if the operation failed */
504                 drv = clear->hcd->driver;
505                 if (drv->clear_tt_buffer_complete)
506                         (drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
507
508                 kfree(clear);
509                 spin_lock_irqsave(&hub->tt.lock, flags);
510         }
511         spin_unlock_irqrestore (&hub->tt.lock, flags);
512 }
513
514 /**
515  * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
516  * @urb: an URB associated with the failed or incomplete split transaction
517  *
518  * High speed HCDs use this to tell the hub driver that some split control or
519  * bulk transaction failed in a way that requires clearing internal state of
520  * a transaction translator.  This is normally detected (and reported) from
521  * interrupt context.
522  *
523  * It may not be possible for that hub to handle additional full (or low)
524  * speed transactions until that state is fully cleared out.
525  */
526 int usb_hub_clear_tt_buffer(struct urb *urb)
527 {
528         struct usb_device       *udev = urb->dev;
529         int                     pipe = urb->pipe;
530         struct usb_tt           *tt = udev->tt;
531         unsigned long           flags;
532         struct usb_tt_clear     *clear;
533
534         /* we've got to cope with an arbitrary number of pending TT clears,
535          * since each TT has "at least two" buffers that can need it (and
536          * there can be many TTs per hub).  even if they're uncommon.
537          */
538         if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
539                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
540                 /* FIXME recover somehow ... RESET_TT? */
541                 return -ENOMEM;
542         }
543
544         /* info that CLEAR_TT_BUFFER needs */
545         clear->tt = tt->multi ? udev->ttport : 1;
546         clear->devinfo = usb_pipeendpoint (pipe);
547         clear->devinfo |= udev->devnum << 4;
548         clear->devinfo |= usb_pipecontrol (pipe)
549                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
550                         : (USB_ENDPOINT_XFER_BULK << 11);
551         if (usb_pipein (pipe))
552                 clear->devinfo |= 1 << 15;
553
554         /* info for completion callback */
555         clear->hcd = bus_to_hcd(udev->bus);
556         clear->ep = urb->ep;
557
558         /* tell keventd to clear state for this TT */
559         spin_lock_irqsave (&tt->lock, flags);
560         list_add_tail (&clear->clear_list, &tt->clear_list);
561         schedule_work(&tt->clear_work);
562         spin_unlock_irqrestore (&tt->lock, flags);
563         return 0;
564 }
565 EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
566
567 /* If do_delay is false, return the number of milliseconds the caller
568  * needs to delay.
569  */
570 static unsigned hub_power_on(struct usb_hub *hub, bool do_delay)
571 {
572         int port1;
573         unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
574         unsigned delay;
575         u16 wHubCharacteristics =
576                         le16_to_cpu(hub->descriptor->wHubCharacteristics);
577
578         /* Enable power on each port.  Some hubs have reserved values
579          * of LPSM (> 2) in their descriptors, even though they are
580          * USB 2.0 hubs.  Some hubs do not implement port-power switching
581          * but only emulate it.  In all cases, the ports won't work
582          * unless we send these messages to the hub.
583          */
584         if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
585                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
586         else
587                 dev_dbg(hub->intfdev, "trying to enable port power on "
588                                 "non-switchable hub\n");
589         for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
590                 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
591
592         /* Wait at least 100 msec for power to become stable */
593         delay = max(pgood_delay, (unsigned) 100);
594         if (do_delay)
595                 msleep(delay);
596         return delay;
597 }
598
599 static int hub_hub_status(struct usb_hub *hub,
600                 u16 *status, u16 *change)
601 {
602         int ret;
603
604         mutex_lock(&hub->status_mutex);
605         ret = get_hub_status(hub->hdev, &hub->status->hub);
606         if (ret < 0)
607                 dev_err (hub->intfdev,
608                         "%s failed (err = %d)\n", __func__, ret);
609         else {
610                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
611                 *change = le16_to_cpu(hub->status->hub.wHubChange); 
612                 ret = 0;
613         }
614         mutex_unlock(&hub->status_mutex);
615         return ret;
616 }
617
618 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
619 {
620         struct usb_device *hdev = hub->hdev;
621         int ret = 0;
622
623         if (hdev->children[port1-1] && set_state)
624                 usb_set_device_state(hdev->children[port1-1],
625                                 USB_STATE_NOTATTACHED);
626         if (!hub->error && !hub_is_superspeed(hub->hdev))
627                 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
628         if (ret)
629                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
630                                 port1, ret);
631         return ret;
632 }
633
634 /*
635  * Disable a port and mark a logical connect-change event, so that some
636  * time later khubd will disconnect() any existing usb_device on the port
637  * and will re-enumerate if there actually is a device attached.
638  */
639 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
640 {
641         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
642         hub_port_disable(hub, port1, 1);
643
644         /* FIXME let caller ask to power down the port:
645          *  - some devices won't enumerate without a VBUS power cycle
646          *  - SRP saves power that way
647          *  - ... new call, TBD ...
648          * That's easy if this hub can switch power per-port, and
649          * khubd reactivates the port later (timer, SRP, etc).
650          * Powerdown must be optional, because of reset/DFU.
651          */
652
653         set_bit(port1, hub->change_bits);
654         kick_khubd(hub);
655 }
656
657 /**
658  * usb_remove_device - disable a device's port on its parent hub
659  * @udev: device to be disabled and removed
660  * Context: @udev locked, must be able to sleep.
661  *
662  * After @udev's port has been disabled, khubd is notified and it will
663  * see that the device has been disconnected.  When the device is
664  * physically unplugged and something is plugged in, the events will
665  * be received and processed normally.
666  */
667 int usb_remove_device(struct usb_device *udev)
668 {
669         struct usb_hub *hub;
670         struct usb_interface *intf;
671
672         if (!udev->parent)      /* Can't remove a root hub */
673                 return -EINVAL;
674         hub = hdev_to_hub(udev->parent);
675         intf = to_usb_interface(hub->intfdev);
676
677         usb_autopm_get_interface(intf);
678         set_bit(udev->portnum, hub->removed_bits);
679         hub_port_logical_disconnect(hub, udev->portnum);
680         usb_autopm_put_interface(intf);
681         return 0;
682 }
683
684 enum hub_activation_type {
685         HUB_INIT, HUB_INIT2, HUB_INIT3,         /* INITs must come first */
686         HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
687 };
688
689 static void hub_init_func2(struct work_struct *ws);
690 static void hub_init_func3(struct work_struct *ws);
691
692 static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
693 {
694         struct usb_device *hdev = hub->hdev;
695         struct usb_hcd *hcd;
696         int ret;
697         int port1;
698         int status;
699         bool need_debounce_delay = false;
700         unsigned delay;
701
702         /* Continue a partial initialization */
703         if (type == HUB_INIT2)
704                 goto init2;
705         if (type == HUB_INIT3)
706                 goto init3;
707
708         /* After a resume, port power should still be on.
709          * For any other type of activation, turn it on.
710          */
711         if (type != HUB_RESUME) {
712
713                 /* Speed up system boot by using a delayed_work for the
714                  * hub's initial power-up delays.  This is pretty awkward
715                  * and the implementation looks like a home-brewed sort of
716                  * setjmp/longjmp, but it saves at least 100 ms for each
717                  * root hub (assuming usbcore is compiled into the kernel
718                  * rather than as a module).  It adds up.
719                  *
720                  * This can't be done for HUB_RESUME or HUB_RESET_RESUME
721                  * because for those activation types the ports have to be
722                  * operational when we return.  In theory this could be done
723                  * for HUB_POST_RESET, but it's easier not to.
724                  */
725                 if (type == HUB_INIT) {
726                         delay = hub_power_on(hub, false);
727                         PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func2);
728                         schedule_delayed_work(&hub->init_work,
729                                         msecs_to_jiffies(delay));
730
731                         /* Suppress autosuspend until init is done */
732                         usb_autopm_get_interface_no_resume(
733                                         to_usb_interface(hub->intfdev));
734                         return;         /* Continues at init2: below */
735                 } else if (type == HUB_RESET_RESUME) {
736                         /* The internal host controller state for the hub device
737                          * may be gone after a host power loss on system resume.
738                          * Update the device's info so the HW knows it's a hub.
739                          */
740                         hcd = bus_to_hcd(hdev->bus);
741                         if (hcd->driver->update_hub_device) {
742                                 ret = hcd->driver->update_hub_device(hcd, hdev,
743                                                 &hub->tt, GFP_NOIO);
744                                 if (ret < 0) {
745                                         dev_err(hub->intfdev, "Host not "
746                                                         "accepting hub info "
747                                                         "update.\n");
748                                         dev_err(hub->intfdev, "LS/FS devices "
749                                                         "and hubs may not work "
750                                                         "under this hub\n.");
751                                 }
752                         }
753                         hub_power_on(hub, true);
754                 } else {
755                         hub_power_on(hub, true);
756                 }
757         }
758  init2:
759
760         /* Check each port and set hub->change_bits to let khubd know
761          * which ports need attention.
762          */
763         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
764                 struct usb_device *udev = hdev->children[port1-1];
765                 u16 portstatus, portchange;
766
767                 portstatus = portchange = 0;
768                 status = hub_port_status(hub, port1, &portstatus, &portchange);
769                 if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
770                         dev_dbg(hub->intfdev,
771                                         "port %d: status %04x change %04x\n",
772                                         port1, portstatus, portchange);
773
774                 /* After anything other than HUB_RESUME (i.e., initialization
775                  * or any sort of reset), every port should be disabled.
776                  * Unconnected ports should likewise be disabled (paranoia),
777                  * and so should ports for which we have no usb_device.
778                  */
779                 if ((portstatus & USB_PORT_STAT_ENABLE) && (
780                                 type != HUB_RESUME ||
781                                 !(portstatus & USB_PORT_STAT_CONNECTION) ||
782                                 !udev ||
783                                 udev->state == USB_STATE_NOTATTACHED)) {
784                         /*
785                          * USB3 protocol ports will automatically transition
786                          * to Enabled state when detect an USB3.0 device attach.
787                          * Do not disable USB3 protocol ports.
788                          */
789                         if (!hub_is_superspeed(hdev)) {
790                                 clear_port_feature(hdev, port1,
791                                                    USB_PORT_FEAT_ENABLE);
792                                 portstatus &= ~USB_PORT_STAT_ENABLE;
793                         } else {
794                                 /* Pretend that power was lost for USB3 devs */
795                                 portstatus &= ~USB_PORT_STAT_ENABLE;
796                         }
797                 }
798
799                 /* Clear status-change flags; we'll debounce later */
800                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
801                         need_debounce_delay = true;
802                         clear_port_feature(hub->hdev, port1,
803                                         USB_PORT_FEAT_C_CONNECTION);
804                 }
805                 if (portchange & USB_PORT_STAT_C_ENABLE) {
806                         need_debounce_delay = true;
807                         clear_port_feature(hub->hdev, port1,
808                                         USB_PORT_FEAT_C_ENABLE);
809                 }
810                 if (portchange & USB_PORT_STAT_C_LINK_STATE) {
811                         need_debounce_delay = true;
812                         clear_port_feature(hub->hdev, port1,
813                                         USB_PORT_FEAT_C_PORT_LINK_STATE);
814                 }
815
816                 /* We can forget about a "removed" device when there's a
817                  * physical disconnect or the connect status changes.
818                  */
819                 if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
820                                 (portchange & USB_PORT_STAT_C_CONNECTION))
821                         clear_bit(port1, hub->removed_bits);
822
823                 if (!udev || udev->state == USB_STATE_NOTATTACHED) {
824                         /* Tell khubd to disconnect the device or
825                          * check for a new connection
826                          */
827                         if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
828                                 set_bit(port1, hub->change_bits);
829
830                 } else if (portstatus & USB_PORT_STAT_ENABLE) {
831                         /* The power session apparently survived the resume.
832                          * If there was an overcurrent or suspend change
833                          * (i.e., remote wakeup request), have khubd
834                          * take care of it.
835                          */
836                         if (portchange)
837                                 set_bit(port1, hub->change_bits);
838
839                 } else if (udev->persist_enabled) {
840 #ifdef CONFIG_PM
841                         udev->reset_resume = 1;
842 #endif
843                         set_bit(port1, hub->change_bits);
844
845                 } else {
846                         /* The power session is gone; tell khubd */
847                         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
848                         set_bit(port1, hub->change_bits);
849                 }
850         }
851
852         /* If no port-status-change flags were set, we don't need any
853          * debouncing.  If flags were set we can try to debounce the
854          * ports all at once right now, instead of letting khubd do them
855          * one at a time later on.
856          *
857          * If any port-status changes do occur during this delay, khubd
858          * will see them later and handle them normally.
859          */
860         if (need_debounce_delay) {
861                 delay = HUB_DEBOUNCE_STABLE;
862
863                 /* Don't do a long sleep inside a workqueue routine */
864                 if (type == HUB_INIT2) {
865                         PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func3);
866                         schedule_delayed_work(&hub->init_work,
867                                         msecs_to_jiffies(delay));
868                         return;         /* Continues at init3: below */
869                 } else {
870                         msleep(delay);
871                 }
872         }
873  init3:
874         hub->quiescing = 0;
875
876         status = usb_submit_urb(hub->urb, GFP_NOIO);
877         if (status < 0)
878                 dev_err(hub->intfdev, "activate --> %d\n", status);
879         if (hub->has_indicators && blinkenlights)
880                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
881
882         /* Scan all ports that need attention */
883         kick_khubd(hub);
884
885         /* Allow autosuspend if it was suppressed */
886         if (type <= HUB_INIT3)
887                 usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
888 }
889
890 /* Implement the continuations for the delays above */
891 static void hub_init_func2(struct work_struct *ws)
892 {
893         struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
894
895         hub_activate(hub, HUB_INIT2);
896 }
897
898 static void hub_init_func3(struct work_struct *ws)
899 {
900         struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
901
902         hub_activate(hub, HUB_INIT3);
903 }
904
905 enum hub_quiescing_type {
906         HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
907 };
908
909 static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
910 {
911         struct usb_device *hdev = hub->hdev;
912         int i;
913
914         cancel_delayed_work_sync(&hub->init_work);
915
916         /* khubd and related activity won't re-trigger */
917         hub->quiescing = 1;
918
919         if (type != HUB_SUSPEND) {
920                 /* Disconnect all the children */
921                 for (i = 0; i < hdev->maxchild; ++i) {
922                         if (hdev->children[i])
923                                 usb_disconnect(&hdev->children[i]);
924                 }
925         }
926
927         /* Stop khubd and related activity */
928         usb_kill_urb(hub->urb);
929         if (hub->has_indicators)
930                 cancel_delayed_work_sync(&hub->leds);
931         if (hub->tt.hub)
932                 cancel_work_sync(&hub->tt.clear_work);
933 }
934
935 /* caller has locked the hub device */
936 static int hub_pre_reset(struct usb_interface *intf)
937 {
938         struct usb_hub *hub = usb_get_intfdata(intf);
939
940         hub_quiesce(hub, HUB_PRE_RESET);
941         return 0;
942 }
943
944 /* caller has locked the hub device */
945 static int hub_post_reset(struct usb_interface *intf)
946 {
947         struct usb_hub *hub = usb_get_intfdata(intf);
948
949         hub_activate(hub, HUB_POST_RESET);
950         return 0;
951 }
952
953 static int hub_configure(struct usb_hub *hub,
954         struct usb_endpoint_descriptor *endpoint)
955 {
956         struct usb_hcd *hcd;
957         struct usb_device *hdev = hub->hdev;
958         struct device *hub_dev = hub->intfdev;
959         u16 hubstatus, hubchange;
960         u16 wHubCharacteristics;
961         unsigned int pipe;
962         int maxp, ret;
963         char *message = "out of memory";
964
965         hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
966         if (!hub->buffer) {
967                 ret = -ENOMEM;
968                 goto fail;
969         }
970
971         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
972         if (!hub->status) {
973                 ret = -ENOMEM;
974                 goto fail;
975         }
976         mutex_init(&hub->status_mutex);
977
978         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
979         if (!hub->descriptor) {
980                 ret = -ENOMEM;
981                 goto fail;
982         }
983
984         if (hub_is_superspeed(hdev) && (hdev->parent != NULL)) {
985                 ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
986                                 HUB_SET_DEPTH, USB_RT_HUB,
987                                 hdev->level - 1, 0, NULL, 0,
988                                 USB_CTRL_SET_TIMEOUT);
989
990                 if (ret < 0) {
991                         message = "can't set hub depth";
992                         goto fail;
993                 }
994         }
995
996         /* Request the entire hub descriptor.
997          * hub->descriptor can handle USB_MAXCHILDREN ports,
998          * but the hub can/will return fewer bytes here.
999          */
1000         ret = get_hub_descriptor(hdev, hub->descriptor);
1001         if (ret < 0) {
1002                 message = "can't read hub descriptor";
1003                 goto fail;
1004         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
1005                 message = "hub has too many ports!";
1006                 ret = -ENODEV;
1007                 goto fail;
1008         }
1009
1010         hdev->maxchild = hub->descriptor->bNbrPorts;
1011         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
1012                 (hdev->maxchild == 1) ? "" : "s");
1013
1014         hub->port_owners = kzalloc(hdev->maxchild * sizeof(void *), GFP_KERNEL);
1015         if (!hub->port_owners) {
1016                 ret = -ENOMEM;
1017                 goto fail;
1018         }
1019
1020         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1021
1022         /* FIXME for USB 3.0, skip for now */
1023         if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
1024                         !(hub_is_superspeed(hdev))) {
1025                 int     i;
1026                 char    portstr [USB_MAXCHILDREN + 1];
1027
1028                 for (i = 0; i < hdev->maxchild; i++)
1029                         portstr[i] = hub->descriptor->u.hs.DeviceRemovable
1030                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
1031                                 ? 'F' : 'R';
1032                 portstr[hdev->maxchild] = 0;
1033                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
1034         } else
1035                 dev_dbg(hub_dev, "standalone hub\n");
1036
1037         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1038                 case 0x00:
1039                         dev_dbg(hub_dev, "ganged power switching\n");
1040                         break;
1041                 case 0x01:
1042                         dev_dbg(hub_dev, "individual port power switching\n");
1043                         break;
1044                 case 0x02:
1045                 case 0x03:
1046                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
1047                         break;
1048         }
1049
1050         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1051                 case 0x00:
1052                         dev_dbg(hub_dev, "global over-current protection\n");
1053                         break;
1054                 case 0x08:
1055                         dev_dbg(hub_dev, "individual port over-current protection\n");
1056                         break;
1057                 case 0x10:
1058                 case 0x18:
1059                         dev_dbg(hub_dev, "no over-current protection\n");
1060                         break;
1061         }
1062
1063         spin_lock_init (&hub->tt.lock);
1064         INIT_LIST_HEAD (&hub->tt.clear_list);
1065         INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1066         switch (hdev->descriptor.bDeviceProtocol) {
1067                 case 0:
1068                         break;
1069                 case 1:
1070                         dev_dbg(hub_dev, "Single TT\n");
1071                         hub->tt.hub = hdev;
1072                         break;
1073                 case 2:
1074                         ret = usb_set_interface(hdev, 0, 1);
1075                         if (ret == 0) {
1076                                 dev_dbg(hub_dev, "TT per port\n");
1077                                 hub->tt.multi = 1;
1078                         } else
1079                                 dev_err(hub_dev, "Using single TT (err %d)\n",
1080                                         ret);
1081                         hub->tt.hub = hdev;
1082                         break;
1083                 case 3:
1084                         /* USB 3.0 hubs don't have a TT */
1085                         break;
1086                 default:
1087                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1088                                 hdev->descriptor.bDeviceProtocol);
1089                         break;
1090         }
1091
1092         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1093         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1094                 case HUB_TTTT_8_BITS:
1095                         if (hdev->descriptor.bDeviceProtocol != 0) {
1096                                 hub->tt.think_time = 666;
1097                                 dev_dbg(hub_dev, "TT requires at most %d "
1098                                                 "FS bit times (%d ns)\n",
1099                                         8, hub->tt.think_time);
1100                         }
1101                         break;
1102                 case HUB_TTTT_16_BITS:
1103                         hub->tt.think_time = 666 * 2;
1104                         dev_dbg(hub_dev, "TT requires at most %d "
1105                                         "FS bit times (%d ns)\n",
1106                                 16, hub->tt.think_time);
1107                         break;
1108                 case HUB_TTTT_24_BITS:
1109                         hub->tt.think_time = 666 * 3;
1110                         dev_dbg(hub_dev, "TT requires at most %d "
1111                                         "FS bit times (%d ns)\n",
1112                                 24, hub->tt.think_time);
1113                         break;
1114                 case HUB_TTTT_32_BITS:
1115                         hub->tt.think_time = 666 * 4;
1116                         dev_dbg(hub_dev, "TT requires at most %d "
1117                                         "FS bit times (%d ns)\n",
1118                                 32, hub->tt.think_time);
1119                         break;
1120         }
1121
1122         /* probe() zeroes hub->indicator[] */
1123         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1124                 hub->has_indicators = 1;
1125                 dev_dbg(hub_dev, "Port indicators are supported\n");
1126         }
1127
1128         dev_dbg(hub_dev, "power on to power good time: %dms\n",
1129                 hub->descriptor->bPwrOn2PwrGood * 2);
1130
1131         /* power budgeting mostly matters with bus-powered hubs,
1132          * and battery-powered root hubs (may provide just 8 mA).
1133          */
1134         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1135         if (ret < 2) {
1136                 message = "can't get hub status";
1137                 goto fail;
1138         }
1139         le16_to_cpus(&hubstatus);
1140         if (hdev == hdev->bus->root_hub) {
1141                 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
1142                         hub->mA_per_port = 500;
1143                 else {
1144                         hub->mA_per_port = hdev->bus_mA;
1145                         hub->limited_power = 1;
1146                 }
1147         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1148                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1149                         hub->descriptor->bHubContrCurrent);
1150                 hub->limited_power = 1;
1151                 if (hdev->maxchild > 0) {
1152                         int remaining = hdev->bus_mA -
1153                                         hub->descriptor->bHubContrCurrent;
1154
1155                         if (remaining < hdev->maxchild * 100)
1156                                 dev_warn(hub_dev,
1157                                         "insufficient power available "
1158                                         "to use all downstream ports\n");
1159                         hub->mA_per_port = 100;         /* 7.2.1.1 */
1160                 }
1161         } else {        /* Self-powered external hub */
1162                 /* FIXME: What about battery-powered external hubs that
1163                  * provide less current per port? */
1164                 hub->mA_per_port = 500;
1165         }
1166         if (hub->mA_per_port < 500)
1167                 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1168                                 hub->mA_per_port);
1169
1170         /* Update the HCD's internal representation of this hub before khubd
1171          * starts getting port status changes for devices under the hub.
1172          */
1173         hcd = bus_to_hcd(hdev->bus);
1174         if (hcd->driver->update_hub_device) {
1175                 ret = hcd->driver->update_hub_device(hcd, hdev,
1176                                 &hub->tt, GFP_KERNEL);
1177                 if (ret < 0) {
1178                         message = "can't update HCD hub info";
1179                         goto fail;
1180                 }
1181         }
1182
1183         ret = hub_hub_status(hub, &hubstatus, &hubchange);
1184         if (ret < 0) {
1185                 message = "can't get hub status";
1186                 goto fail;
1187         }
1188
1189         /* local power status reports aren't always correct */
1190         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1191                 dev_dbg(hub_dev, "local power source is %s\n",
1192                         (hubstatus & HUB_STATUS_LOCAL_POWER)
1193                         ? "lost (inactive)" : "good");
1194
1195         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1196                 dev_dbg(hub_dev, "%sover-current condition exists\n",
1197                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1198
1199         /* set up the interrupt endpoint
1200          * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1201          * bytes as USB2.0[11.12.3] says because some hubs are known
1202          * to send more data (and thus cause overflow). For root hubs,
1203          * maxpktsize is defined in hcd.c's fake endpoint descriptors
1204          * to be big enough for at least USB_MAXCHILDREN ports. */
1205         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1206         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
1207
1208         if (maxp > sizeof(*hub->buffer))
1209                 maxp = sizeof(*hub->buffer);
1210
1211         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1212         if (!hub->urb) {
1213                 ret = -ENOMEM;
1214                 goto fail;
1215         }
1216
1217         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1218                 hub, endpoint->bInterval);
1219
1220         /* maybe cycle the hub leds */
1221         if (hub->has_indicators && blinkenlights)
1222                 hub->indicator [0] = INDICATOR_CYCLE;
1223
1224         hub_activate(hub, HUB_INIT);
1225         return 0;
1226
1227 fail:
1228         dev_err (hub_dev, "config failed, %s (err %d)\n",
1229                         message, ret);
1230         /* hub_disconnect() frees urb and descriptor */
1231         return ret;
1232 }
1233
1234 static void hub_release(struct kref *kref)
1235 {
1236         struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1237
1238         usb_put_intf(to_usb_interface(hub->intfdev));
1239         kfree(hub);
1240 }
1241
1242 static unsigned highspeed_hubs;
1243
1244 static void hub_disconnect(struct usb_interface *intf)
1245 {
1246         struct usb_hub *hub = usb_get_intfdata (intf);
1247
1248         /* Take the hub off the event list and don't let it be added again */
1249         spin_lock_irq(&hub_event_lock);
1250         if (!list_empty(&hub->event_list)) {
1251                 list_del_init(&hub->event_list);
1252                 usb_autopm_put_interface_no_suspend(intf);
1253         }
1254         hub->disconnected = 1;
1255         spin_unlock_irq(&hub_event_lock);
1256
1257         /* Disconnect all children and quiesce the hub */
1258         hub->error = 0;
1259         hub_quiesce(hub, HUB_DISCONNECT);
1260
1261         usb_set_intfdata (intf, NULL);
1262         hub->hdev->maxchild = 0;
1263
1264         if (hub->hdev->speed == USB_SPEED_HIGH)
1265                 highspeed_hubs--;
1266
1267         usb_free_urb(hub->urb);
1268         kfree(hub->port_owners);
1269         kfree(hub->descriptor);
1270         kfree(hub->status);
1271         kfree(hub->buffer);
1272
1273         kref_put(&hub->kref, hub_release);
1274 }
1275
1276 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1277 {
1278         struct usb_host_interface *desc;
1279         struct usb_endpoint_descriptor *endpoint;
1280         struct usb_device *hdev;
1281         struct usb_hub *hub;
1282
1283         desc = intf->cur_altsetting;
1284         hdev = interface_to_usbdev(intf);
1285
1286         /* Hubs have proper suspend/resume support.  USB 3.0 device suspend is
1287          * different from USB 2.0/1.1 device suspend, and unfortunately we
1288          * don't support it yet.  So leave autosuspend disabled for USB 3.0
1289          * external hubs for now.  Enable autosuspend for USB 3.0 roothubs,
1290          * since that isn't a "real" hub.
1291          */
1292         if (!hub_is_superspeed(hdev) || !hdev->parent)
1293                 usb_enable_autosuspend(hdev);
1294
1295         if (hdev->level == MAX_TOPO_LEVEL) {
1296                 dev_err(&intf->dev,
1297                         "Unsupported bus topology: hub nested too deep\n");
1298                 return -E2BIG;
1299         }
1300
1301 #ifdef  CONFIG_USB_OTG_BLACKLIST_HUB
1302         if (hdev->parent) {
1303                 dev_warn(&intf->dev, "ignoring external hub\n");
1304                 return -ENODEV;
1305         }
1306 #endif
1307
1308         /* Some hubs have a subclass of 1, which AFAICT according to the */
1309         /*  specs is not defined, but it works */
1310         if ((desc->desc.bInterfaceSubClass != 0) &&
1311             (desc->desc.bInterfaceSubClass != 1)) {
1312 descriptor_error:
1313                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
1314                 return -EIO;
1315         }
1316
1317         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
1318         if (desc->desc.bNumEndpoints != 1)
1319                 goto descriptor_error;
1320
1321         endpoint = &desc->endpoint[0].desc;
1322
1323         /* If it's not an interrupt in endpoint, we'd better punt! */
1324         if (!usb_endpoint_is_int_in(endpoint))
1325                 goto descriptor_error;
1326
1327         /* We found a hub */
1328         dev_info (&intf->dev, "USB hub found\n");
1329
1330         hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1331         if (!hub) {
1332                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
1333                 return -ENOMEM;
1334         }
1335
1336         kref_init(&hub->kref);
1337         INIT_LIST_HEAD(&hub->event_list);
1338         hub->intfdev = &intf->dev;
1339         hub->hdev = hdev;
1340         INIT_DELAYED_WORK(&hub->leds, led_work);
1341         INIT_DELAYED_WORK(&hub->init_work, NULL);
1342         usb_get_intf(intf);
1343
1344         usb_set_intfdata (intf, hub);
1345         intf->needs_remote_wakeup = 1;
1346
1347         if (hdev->speed == USB_SPEED_HIGH)
1348                 highspeed_hubs++;
1349
1350         if (hub_configure(hub, endpoint) >= 0)
1351                 return 0;
1352
1353         hub_disconnect (intf);
1354         return -ENODEV;
1355 }
1356
1357 /* No BKL needed */
1358 static int
1359 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1360 {
1361         struct usb_device *hdev = interface_to_usbdev (intf);
1362
1363         /* assert ifno == 0 (part of hub spec) */
1364         switch (code) {
1365         case USBDEVFS_HUB_PORTINFO: {
1366                 struct usbdevfs_hub_portinfo *info = user_data;
1367                 int i;
1368
1369                 spin_lock_irq(&device_state_lock);
1370                 if (hdev->devnum <= 0)
1371                         info->nports = 0;
1372                 else {
1373                         info->nports = hdev->maxchild;
1374                         for (i = 0; i < info->nports; i++) {
1375                                 if (hdev->children[i] == NULL)
1376                                         info->port[i] = 0;
1377                                 else
1378                                         info->port[i] =
1379                                                 hdev->children[i]->devnum;
1380                         }
1381                 }
1382                 spin_unlock_irq(&device_state_lock);
1383
1384                 return info->nports + 1;
1385                 }
1386
1387         default:
1388                 return -ENOSYS;
1389         }
1390 }
1391
1392 /*
1393  * Allow user programs to claim ports on a hub.  When a device is attached
1394  * to one of these "claimed" ports, the program will "own" the device.
1395  */
1396 static int find_port_owner(struct usb_device *hdev, unsigned port1,
1397                 void ***ppowner)
1398 {
1399         if (hdev->state == USB_STATE_NOTATTACHED)
1400                 return -ENODEV;
1401         if (port1 == 0 || port1 > hdev->maxchild)
1402                 return -EINVAL;
1403
1404         /* This assumes that devices not managed by the hub driver
1405          * will always have maxchild equal to 0.
1406          */
1407         *ppowner = &(hdev_to_hub(hdev)->port_owners[port1 - 1]);
1408         return 0;
1409 }
1410
1411 /* In the following three functions, the caller must hold hdev's lock */
1412 int usb_hub_claim_port(struct usb_device *hdev, unsigned port1, void *owner)
1413 {
1414         int rc;
1415         void **powner;
1416
1417         rc = find_port_owner(hdev, port1, &powner);
1418         if (rc)
1419                 return rc;
1420         if (*powner)
1421                 return -EBUSY;
1422         *powner = owner;
1423         return rc;
1424 }
1425
1426 int usb_hub_release_port(struct usb_device *hdev, unsigned port1, void *owner)
1427 {
1428         int rc;
1429         void **powner;
1430
1431         rc = find_port_owner(hdev, port1, &powner);
1432         if (rc)
1433                 return rc;
1434         if (*powner != owner)
1435                 return -ENOENT;
1436         *powner = NULL;
1437         return rc;
1438 }
1439
1440 void usb_hub_release_all_ports(struct usb_device *hdev, void *owner)
1441 {
1442         int n;
1443         void **powner;
1444
1445         n = find_port_owner(hdev, 1, &powner);
1446         if (n == 0) {
1447                 for (; n < hdev->maxchild; (++n, ++powner)) {
1448                         if (*powner == owner)
1449                                 *powner = NULL;
1450                 }
1451         }
1452 }
1453
1454 /* The caller must hold udev's lock */
1455 bool usb_device_is_owned(struct usb_device *udev)
1456 {
1457         struct usb_hub *hub;
1458
1459         if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
1460                 return false;
1461         hub = hdev_to_hub(udev->parent);
1462         return !!hub->port_owners[udev->portnum - 1];
1463 }
1464
1465
1466 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1467 {
1468         int i;
1469
1470         for (i = 0; i < udev->maxchild; ++i) {
1471                 if (udev->children[i])
1472                         recursively_mark_NOTATTACHED(udev->children[i]);
1473         }
1474         if (udev->state == USB_STATE_SUSPENDED)
1475                 udev->active_duration -= jiffies;
1476         udev->state = USB_STATE_NOTATTACHED;
1477 }
1478
1479 /**
1480  * usb_set_device_state - change a device's current state (usbcore, hcds)
1481  * @udev: pointer to device whose state should be changed
1482  * @new_state: new state value to be stored
1483  *
1484  * udev->state is _not_ fully protected by the device lock.  Although
1485  * most transitions are made only while holding the lock, the state can
1486  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1487  * is so that devices can be marked as disconnected as soon as possible,
1488  * without having to wait for any semaphores to be released.  As a result,
1489  * all changes to any device's state must be protected by the
1490  * device_state_lock spinlock.
1491  *
1492  * Once a device has been added to the device tree, all changes to its state
1493  * should be made using this routine.  The state should _not_ be set directly.
1494  *
1495  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1496  * Otherwise udev->state is set to new_state, and if new_state is
1497  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1498  * to USB_STATE_NOTATTACHED.
1499  */
1500 void usb_set_device_state(struct usb_device *udev,
1501                 enum usb_device_state new_state)
1502 {
1503         unsigned long flags;
1504         int wakeup = -1;
1505
1506         spin_lock_irqsave(&device_state_lock, flags);
1507         if (udev->state == USB_STATE_NOTATTACHED)
1508                 ;       /* do nothing */
1509         else if (new_state != USB_STATE_NOTATTACHED) {
1510
1511                 /* root hub wakeup capabilities are managed out-of-band
1512                  * and may involve silicon errata ... ignore them here.
1513                  */
1514                 if (udev->parent) {
1515                         if (udev->state == USB_STATE_SUSPENDED
1516                                         || new_state == USB_STATE_SUSPENDED)
1517                                 ;       /* No change to wakeup settings */
1518                         else if (new_state == USB_STATE_CONFIGURED)
1519                                 wakeup = udev->actconfig->desc.bmAttributes
1520                                          & USB_CONFIG_ATT_WAKEUP;
1521                         else
1522                                 wakeup = 0;
1523                 }
1524                 if (udev->state == USB_STATE_SUSPENDED &&
1525                         new_state != USB_STATE_SUSPENDED)
1526                         udev->active_duration -= jiffies;
1527                 else if (new_state == USB_STATE_SUSPENDED &&
1528                                 udev->state != USB_STATE_SUSPENDED)
1529                         udev->active_duration += jiffies;
1530                 udev->state = new_state;
1531         } else
1532                 recursively_mark_NOTATTACHED(udev);
1533         spin_unlock_irqrestore(&device_state_lock, flags);
1534         if (wakeup >= 0)
1535                 device_set_wakeup_capable(&udev->dev, wakeup);
1536 }
1537 EXPORT_SYMBOL_GPL(usb_set_device_state);
1538
1539 /*
1540  * Choose a device number.
1541  *
1542  * Device numbers are used as filenames in usbfs.  On USB-1.1 and
1543  * USB-2.0 buses they are also used as device addresses, however on
1544  * USB-3.0 buses the address is assigned by the controller hardware
1545  * and it usually is not the same as the device number.
1546  *
1547  * WUSB devices are simple: they have no hubs behind, so the mapping
1548  * device <-> virtual port number becomes 1:1. Why? to simplify the
1549  * life of the device connection logic in
1550  * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
1551  * handshake we need to assign a temporary address in the unauthorized
1552  * space. For simplicity we use the first virtual port number found to
1553  * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
1554  * and that becomes it's address [X < 128] or its unauthorized address
1555  * [X | 0x80].
1556  *
1557  * We add 1 as an offset to the one-based USB-stack port number
1558  * (zero-based wusb virtual port index) for two reasons: (a) dev addr
1559  * 0 is reserved by USB for default address; (b) Linux's USB stack
1560  * uses always #1 for the root hub of the controller. So USB stack's
1561  * port #1, which is wusb virtual-port #0 has address #2.
1562  *
1563  * Devices connected under xHCI are not as simple.  The host controller
1564  * supports virtualization, so the hardware assigns device addresses and
1565  * the HCD must setup data structures before issuing a set address
1566  * command to the hardware.
1567  */
1568 static void choose_devnum(struct usb_device *udev)
1569 {
1570         int             devnum;
1571         struct usb_bus  *bus = udev->bus;
1572
1573         /* If khubd ever becomes multithreaded, this will need a lock */
1574         if (udev->wusb) {
1575                 devnum = udev->portnum + 1;
1576                 BUG_ON(test_bit(devnum, bus->devmap.devicemap));
1577         } else {
1578                 /* Try to allocate the next devnum beginning at
1579                  * bus->devnum_next. */
1580                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1581                                             bus->devnum_next);
1582                 if (devnum >= 128)
1583                         devnum = find_next_zero_bit(bus->devmap.devicemap,
1584                                                     128, 1);
1585                 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1586         }
1587         if (devnum < 128) {
1588                 set_bit(devnum, bus->devmap.devicemap);
1589                 udev->devnum = devnum;
1590         }
1591 }
1592
1593 static void release_devnum(struct usb_device *udev)
1594 {
1595         if (udev->devnum > 0) {
1596                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1597                 udev->devnum = -1;
1598         }
1599 }
1600
1601 static void update_devnum(struct usb_device *udev, int devnum)
1602 {
1603         /* The address for a WUSB device is managed by wusbcore. */
1604         if (!udev->wusb)
1605                 udev->devnum = devnum;
1606 }
1607
1608 static void hub_free_dev(struct usb_device *udev)
1609 {
1610         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1611
1612         /* Root hubs aren't real devices, so don't free HCD resources */
1613         if (hcd->driver->free_dev && udev->parent)
1614                 hcd->driver->free_dev(hcd, udev);
1615 }
1616
1617 /**
1618  * usb_disconnect - disconnect a device (usbcore-internal)
1619  * @pdev: pointer to device being disconnected
1620  * Context: !in_interrupt ()
1621  *
1622  * Something got disconnected. Get rid of it and all of its children.
1623  *
1624  * If *pdev is a normal device then the parent hub must already be locked.
1625  * If *pdev is a root hub then this routine will acquire the
1626  * usb_bus_list_lock on behalf of the caller.
1627  *
1628  * Only hub drivers (including virtual root hub drivers for host
1629  * controllers) should ever call this.
1630  *
1631  * This call is synchronous, and may not be used in an interrupt context.
1632  */
1633 void usb_disconnect(struct usb_device **pdev)
1634 {
1635         struct usb_device       *udev = *pdev;
1636         int                     i;
1637         struct usb_hcd          *hcd = bus_to_hcd(udev->bus);
1638
1639         if (!udev) {
1640                 pr_debug ("%s nodev\n", __func__);
1641                 return;
1642         }
1643
1644         /* mark the device as inactive, so any further urb submissions for
1645          * this device (and any of its children) will fail immediately.
1646          * this quiesces everything except pending urbs.
1647          */
1648         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1649         dev_info(&udev->dev, "USB disconnect, device number %d\n",
1650                         udev->devnum);
1651
1652         usb_lock_device(udev);
1653
1654         /* Free up all the children before we remove this device */
1655         for (i = 0; i < USB_MAXCHILDREN; i++) {
1656                 if (udev->children[i])
1657                         usb_disconnect(&udev->children[i]);
1658         }
1659
1660         /* deallocate hcd/hardware state ... nuking all pending urbs and
1661          * cleaning up all state associated with the current configuration
1662          * so that the hardware is now fully quiesced.
1663          */
1664         dev_dbg (&udev->dev, "unregistering device\n");
1665         mutex_lock(hcd->bandwidth_mutex);
1666         usb_disable_device(udev, 0);
1667         mutex_unlock(hcd->bandwidth_mutex);
1668         usb_hcd_synchronize_unlinks(udev);
1669
1670         usb_remove_ep_devs(&udev->ep0);
1671         usb_unlock_device(udev);
1672
1673         /* Unregister the device.  The device driver is responsible
1674          * for de-configuring the device and invoking the remove-device
1675          * notifier chain (used by usbfs and possibly others).
1676          */
1677         device_del(&udev->dev);
1678
1679         /* Free the device number and delete the parent's children[]
1680          * (or root_hub) pointer.
1681          */
1682         release_devnum(udev);
1683
1684         /* Avoid races with recursively_mark_NOTATTACHED() */
1685         spin_lock_irq(&device_state_lock);
1686         *pdev = NULL;
1687         spin_unlock_irq(&device_state_lock);
1688
1689         hub_free_dev(udev);
1690
1691         put_device(&udev->dev);
1692 }
1693
1694 #ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
1695 static void show_string(struct usb_device *udev, char *id, char *string)
1696 {
1697         if (!string)
1698                 return;
1699         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1700 }
1701
1702 static void announce_device(struct usb_device *udev)
1703 {
1704         dev_info(&udev->dev, "New USB device found, idVendor=%04x, idProduct=%04x\n",
1705                 le16_to_cpu(udev->descriptor.idVendor),
1706                 le16_to_cpu(udev->descriptor.idProduct));
1707         dev_info(&udev->dev,
1708                 "New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
1709                 udev->descriptor.iManufacturer,
1710                 udev->descriptor.iProduct,
1711                 udev->descriptor.iSerialNumber);
1712         show_string(udev, "Product", udev->product);
1713         show_string(udev, "Manufacturer", udev->manufacturer);
1714         show_string(udev, "SerialNumber", udev->serial);
1715 }
1716 #else
1717 static inline void announce_device(struct usb_device *udev) { }
1718 #endif
1719
1720 #ifdef  CONFIG_USB_OTG
1721 #include "otg_whitelist.h"
1722 #endif
1723
1724 /**
1725  * usb_enumerate_device_otg - FIXME (usbcore-internal)
1726  * @udev: newly addressed device (in ADDRESS state)
1727  *
1728  * Finish enumeration for On-The-Go devices
1729  */
1730 static int usb_enumerate_device_otg(struct usb_device *udev)
1731 {
1732         int err = 0;
1733
1734 #ifdef  CONFIG_USB_OTG
1735         /*
1736          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1737          * to wake us after we've powered off VBUS; and HNP, switching roles
1738          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1739          */
1740         if (!udev->bus->is_b_host
1741                         && udev->config
1742                         && udev->parent == udev->bus->root_hub) {
1743                 struct usb_otg_descriptor       *desc = NULL;
1744                 struct usb_bus                  *bus = udev->bus;
1745
1746                 /* descriptor may appear anywhere in config */
1747                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1748                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1749                                         USB_DT_OTG, (void **) &desc) == 0) {
1750                         if (desc->bmAttributes & USB_OTG_HNP) {
1751                                 unsigned                port1 = udev->portnum;
1752
1753                                 dev_info(&udev->dev,
1754                                         "Dual-Role OTG device on %sHNP port\n",
1755                                         (port1 == bus->otg_port)
1756                                                 ? "" : "non-");
1757
1758                                 /* enable HNP before suspend, it's simpler */
1759                                 if (port1 == bus->otg_port)
1760                                         bus->b_hnp_enable = 1;
1761                                 err = usb_control_msg(udev,
1762                                         usb_sndctrlpipe(udev, 0),
1763                                         USB_REQ_SET_FEATURE, 0,
1764                                         bus->b_hnp_enable
1765                                                 ? USB_DEVICE_B_HNP_ENABLE
1766                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1767                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1768                                 if (err < 0) {
1769                                         /* OTG MESSAGE: report errors here,
1770                                          * customize to match your product.
1771                                          */
1772                                         dev_info(&udev->dev,
1773                                                 "can't set HNP mode: %d\n",
1774                                                 err);
1775                                         bus->b_hnp_enable = 0;
1776                                 }
1777                         }
1778                 }
1779         }
1780
1781         if (!is_targeted(udev)) {
1782
1783                 /* Maybe it can talk to us, though we can't talk to it.
1784                  * (Includes HNP test device.)
1785                  */
1786                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1787                         err = usb_port_suspend(udev, PMSG_SUSPEND);
1788                         if (err < 0)
1789                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1790                 }
1791                 err = -ENOTSUPP;
1792                 goto fail;
1793         }
1794 fail:
1795 #endif
1796         return err;
1797 }
1798
1799
1800 /**
1801  * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
1802  * @udev: newly addressed device (in ADDRESS state)
1803  *
1804  * This is only called by usb_new_device() and usb_authorize_device()
1805  * and FIXME -- all comments that apply to them apply here wrt to
1806  * environment.
1807  *
1808  * If the device is WUSB and not authorized, we don't attempt to read
1809  * the string descriptors, as they will be errored out by the device
1810  * until it has been authorized.
1811  */
1812 static int usb_enumerate_device(struct usb_device *udev)
1813 {
1814         int err;
1815
1816         if (udev->config == NULL) {
1817                 err = usb_get_configuration(udev);
1818                 if (err < 0) {
1819                         dev_err(&udev->dev, "can't read configurations, error %d\n",
1820                                 err);
1821                         goto fail;
1822                 }
1823         }
1824         if (udev->wusb == 1 && udev->authorized == 0) {
1825                 udev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1826                 udev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1827                 udev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1828         }
1829         else {
1830                 /* read the standard strings and cache them if present */
1831                 udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1832                 udev->manufacturer = usb_cache_string(udev,
1833                                                       udev->descriptor.iManufacturer);
1834                 udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1835         }
1836         err = usb_enumerate_device_otg(udev);
1837 fail:
1838         return err;
1839 }
1840
1841
1842 /**
1843  * usb_new_device - perform initial device setup (usbcore-internal)
1844  * @udev: newly addressed device (in ADDRESS state)
1845  *
1846  * This is called with devices which have been detected but not fully
1847  * enumerated.  The device descriptor is available, but not descriptors
1848  * for any device configuration.  The caller must have locked either
1849  * the parent hub (if udev is a normal device) or else the
1850  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1851  * udev has already been installed, but udev is not yet visible through
1852  * sysfs or other filesystem code.
1853  *
1854  * It will return if the device is configured properly or not.  Zero if
1855  * the interface was registered with the driver core; else a negative
1856  * errno value.
1857  *
1858  * This call is synchronous, and may not be used in an interrupt context.
1859  *
1860  * Only the hub driver or root-hub registrar should ever call this.
1861  */
1862 int usb_new_device(struct usb_device *udev)
1863 {
1864         int err;
1865
1866         if (udev->parent) {
1867                 /* Initialize non-root-hub device wakeup to disabled;
1868                  * device (un)configuration controls wakeup capable
1869                  * sysfs power/wakeup controls wakeup enabled/disabled
1870                  */
1871                 device_init_wakeup(&udev->dev, 0);
1872         }
1873
1874         /* Tell the runtime-PM framework the device is active */
1875         pm_runtime_set_active(&udev->dev);
1876         pm_runtime_get_noresume(&udev->dev);
1877         pm_runtime_use_autosuspend(&udev->dev);
1878         pm_runtime_enable(&udev->dev);
1879
1880         /* By default, forbid autosuspend for all devices.  It will be
1881          * allowed for hubs during binding.
1882          */
1883         usb_disable_autosuspend(udev);
1884
1885         err = usb_enumerate_device(udev);       /* Read descriptors */
1886         if (err < 0)
1887                 goto fail;
1888         dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
1889                         udev->devnum, udev->bus->busnum,
1890                         (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1891         /* export the usbdev device-node for libusb */
1892         udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
1893                         (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1894
1895         /* Tell the world! */
1896         announce_device(udev);
1897
1898         device_enable_async_suspend(&udev->dev);
1899         /* Register the device.  The device driver is responsible
1900          * for configuring the device and invoking the add-device
1901          * notifier chain (used by usbfs and possibly others).
1902          */
1903         err = device_add(&udev->dev);
1904         if (err) {
1905                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1906                 goto fail;
1907         }
1908
1909         (void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
1910         usb_mark_last_busy(udev);
1911         pm_runtime_put_sync_autosuspend(&udev->dev);
1912         return err;
1913
1914 fail:
1915         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1916         pm_runtime_disable(&udev->dev);
1917         pm_runtime_set_suspended(&udev->dev);
1918         return err;
1919 }
1920
1921
1922 /**
1923  * usb_deauthorize_device - deauthorize a device (usbcore-internal)
1924  * @usb_dev: USB device
1925  *
1926  * Move the USB device to a very basic state where interfaces are disabled
1927  * and the device is in fact unconfigured and unusable.
1928  *
1929  * We share a lock (that we have) with device_del(), so we need to
1930  * defer its call.
1931  */
1932 int usb_deauthorize_device(struct usb_device *usb_dev)
1933 {
1934         usb_lock_device(usb_dev);
1935         if (usb_dev->authorized == 0)
1936                 goto out_unauthorized;
1937
1938         usb_dev->authorized = 0;
1939         usb_set_configuration(usb_dev, -1);
1940
1941         kfree(usb_dev->product);
1942         usb_dev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1943         kfree(usb_dev->manufacturer);
1944         usb_dev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1945         kfree(usb_dev->serial);
1946         usb_dev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1947
1948         usb_destroy_configuration(usb_dev);
1949         usb_dev->descriptor.bNumConfigurations = 0;
1950
1951 out_unauthorized:
1952         usb_unlock_device(usb_dev);
1953         return 0;
1954 }
1955
1956
1957 int usb_authorize_device(struct usb_device *usb_dev)
1958 {
1959         int result = 0, c;
1960
1961         usb_lock_device(usb_dev);
1962         if (usb_dev->authorized == 1)
1963                 goto out_authorized;
1964
1965         result = usb_autoresume_device(usb_dev);
1966         if (result < 0) {
1967                 dev_err(&usb_dev->dev,
1968                         "can't autoresume for authorization: %d\n", result);
1969                 goto error_autoresume;
1970         }
1971         result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
1972         if (result < 0) {
1973                 dev_err(&usb_dev->dev, "can't re-read device descriptor for "
1974                         "authorization: %d\n", result);
1975                 goto error_device_descriptor;
1976         }
1977
1978         kfree(usb_dev->product);
1979         usb_dev->product = NULL;
1980         kfree(usb_dev->manufacturer);
1981         usb_dev->manufacturer = NULL;
1982         kfree(usb_dev->serial);
1983         usb_dev->serial = NULL;
1984
1985         usb_dev->authorized = 1;
1986         result = usb_enumerate_device(usb_dev);
1987         if (result < 0)
1988                 goto error_enumerate;
1989         /* Choose and set the configuration.  This registers the interfaces
1990          * with the driver core and lets interface drivers bind to them.
1991          */
1992         c = usb_choose_configuration(usb_dev);
1993         if (c >= 0) {
1994                 result = usb_set_configuration(usb_dev, c);
1995                 if (result) {
1996                         dev_err(&usb_dev->dev,
1997                                 "can't set config #%d, error %d\n", c, result);
1998                         /* This need not be fatal.  The user can try to
1999                          * set other configurations. */
2000                 }
2001         }
2002         dev_info(&usb_dev->dev, "authorized to connect\n");
2003
2004 error_enumerate:
2005 error_device_descriptor:
2006         usb_autosuspend_device(usb_dev);
2007 error_autoresume:
2008 out_authorized:
2009         usb_unlock_device(usb_dev);     // complements locktree
2010         return result;
2011 }
2012
2013
2014 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
2015 static unsigned hub_is_wusb(struct usb_hub *hub)
2016 {
2017         struct usb_hcd *hcd;
2018         if (hub->hdev->parent != NULL)  /* not a root hub? */
2019                 return 0;
2020         hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
2021         return hcd->wireless;
2022 }
2023
2024
2025 #define PORT_RESET_TRIES        5
2026 #define SET_ADDRESS_TRIES       2
2027 #define GET_DESCRIPTOR_TRIES    2
2028 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
2029 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
2030
2031 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
2032 #define HUB_SHORT_RESET_TIME    10
2033 #define HUB_LONG_RESET_TIME     200
2034 #define HUB_RESET_TIMEOUT       500
2035
2036 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
2037                                 struct usb_device *udev, unsigned int delay)
2038 {
2039         int delay_time, ret;
2040         u16 portstatus;
2041         u16 portchange;
2042
2043         for (delay_time = 0;
2044                         delay_time < HUB_RESET_TIMEOUT;
2045                         delay_time += delay) {
2046                 /* wait to give the device a chance to reset */
2047                 msleep(delay);
2048
2049                 /* read and decode port status */
2050                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2051                 if (ret < 0)
2052                         return ret;
2053
2054                 /* Device went away? */
2055                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
2056                         return -ENOTCONN;
2057
2058                 /* bomb out completely if the connection bounced */
2059                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
2060                         return -ENOTCONN;
2061
2062                 /* if we`ve finished resetting, then break out of the loop */
2063                 if (!(portstatus & USB_PORT_STAT_RESET) &&
2064                     (portstatus & USB_PORT_STAT_ENABLE)) {
2065                         if (hub_is_wusb(hub))
2066                                 udev->speed = USB_SPEED_WIRELESS;
2067                         else if (hub_is_superspeed(hub->hdev))
2068                                 udev->speed = USB_SPEED_SUPER;
2069                         else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
2070                                 udev->speed = USB_SPEED_HIGH;
2071                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
2072                                 udev->speed = USB_SPEED_LOW;
2073                         else
2074                                 udev->speed = USB_SPEED_FULL;
2075                         return 0;
2076                 }
2077
2078                 /* switch to the long delay after two short delay failures */
2079                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
2080                         delay = HUB_LONG_RESET_TIME;
2081
2082                 dev_dbg (hub->intfdev,
2083                         "port %d not reset yet, waiting %dms\n",
2084                         port1, delay);
2085         }
2086
2087         return -EBUSY;
2088 }
2089
2090 static int hub_port_reset(struct usb_hub *hub, int port1,
2091                                 struct usb_device *udev, unsigned int delay)
2092 {
2093         int i, status;
2094         struct usb_hcd *hcd;
2095
2096         hcd = bus_to_hcd(udev->bus);
2097         /* Block EHCI CF initialization during the port reset.
2098          * Some companion controllers don't like it when they mix.
2099          */
2100         down_read(&ehci_cf_port_reset_rwsem);
2101
2102         /* Reset the port */
2103         for (i = 0; i < PORT_RESET_TRIES; i++) {
2104                 status = set_port_feature(hub->hdev,
2105                                 port1, USB_PORT_FEAT_RESET);
2106                 if (status)
2107                         dev_err(hub->intfdev,
2108                                         "cannot reset port %d (err = %d)\n",
2109                                         port1, status);
2110                 else {
2111                         status = hub_port_wait_reset(hub, port1, udev, delay);
2112                         if (status && status != -ENOTCONN)
2113                                 dev_dbg(hub->intfdev,
2114                                                 "port_wait_reset: err = %d\n",
2115                                                 status);
2116                 }
2117
2118                 /* return on disconnect or reset */
2119                 switch (status) {
2120                 case 0:
2121                         /* TRSTRCY = 10 ms; plus some extra */
2122                         msleep(10 + 40);
2123                         update_devnum(udev, 0);
2124                         if (hcd->driver->reset_device) {
2125                                 status = hcd->driver->reset_device(hcd, udev);
2126                                 if (status < 0) {
2127                                         dev_err(&udev->dev, "Cannot reset "
2128                                                         "HCD device state\n");
2129                                         break;
2130                                 }
2131                         }
2132                         /* FALL THROUGH */
2133                 case -ENOTCONN:
2134                 case -ENODEV:
2135                         clear_port_feature(hub->hdev,
2136                                 port1, USB_PORT_FEAT_C_RESET);
2137                         /* FIXME need disconnect() for NOTATTACHED device */
2138                         usb_set_device_state(udev, status
2139                                         ? USB_STATE_NOTATTACHED
2140                                         : USB_STATE_DEFAULT);
2141                         goto done;
2142                 }
2143
2144                 dev_dbg (hub->intfdev,
2145                         "port %d not enabled, trying reset again...\n",
2146                         port1);
2147                 delay = HUB_LONG_RESET_TIME;
2148         }
2149
2150         dev_err (hub->intfdev,
2151                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
2152                 port1);
2153
2154  done:
2155         up_read(&ehci_cf_port_reset_rwsem);
2156         return status;
2157 }
2158
2159 /* Warm reset a USB3 protocol port */
2160 static int hub_port_warm_reset(struct usb_hub *hub, int port)
2161 {
2162         int ret;
2163         u16 portstatus, portchange;
2164
2165         if (!hub_is_superspeed(hub->hdev)) {
2166                 dev_err(hub->intfdev, "only USB3 hub support warm reset\n");
2167                 return -EINVAL;
2168         }
2169
2170         /* Warm reset the port */
2171         ret = set_port_feature(hub->hdev,
2172                                 port, USB_PORT_FEAT_BH_PORT_RESET);
2173         if (ret) {
2174                 dev_err(hub->intfdev, "cannot warm reset port %d\n", port);
2175                 return ret;
2176         }
2177
2178         msleep(20);
2179         ret = hub_port_status(hub, port, &portstatus, &portchange);
2180
2181         if (portchange & USB_PORT_STAT_C_RESET)
2182                 clear_port_feature(hub->hdev, port, USB_PORT_FEAT_C_RESET);
2183
2184         if (portchange & USB_PORT_STAT_C_BH_RESET)
2185                 clear_port_feature(hub->hdev, port,
2186                                         USB_PORT_FEAT_C_BH_PORT_RESET);
2187
2188         if (portchange & USB_PORT_STAT_C_LINK_STATE)
2189                 clear_port_feature(hub->hdev, port,
2190                                         USB_PORT_FEAT_C_PORT_LINK_STATE);
2191
2192         return ret;
2193 }
2194
2195 /* Check if a port is power on */
2196 static int port_is_power_on(struct usb_hub *hub, unsigned portstatus)
2197 {
2198         int ret = 0;
2199
2200         if (hub_is_superspeed(hub->hdev)) {
2201                 if (portstatus & USB_SS_PORT_STAT_POWER)
2202                         ret = 1;
2203         } else {
2204                 if (portstatus & USB_PORT_STAT_POWER)
2205                         ret = 1;
2206         }
2207
2208         return ret;
2209 }
2210
2211 #ifdef  CONFIG_PM
2212
2213 /* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */
2214 static int port_is_suspended(struct usb_hub *hub, unsigned portstatus)
2215 {
2216         int ret = 0;
2217
2218         if (hub_is_superspeed(hub->hdev)) {
2219                 if ((portstatus & USB_PORT_STAT_LINK_STATE)
2220                                 == USB_SS_PORT_LS_U3)
2221                         ret = 1;
2222         } else {
2223                 if (portstatus & USB_PORT_STAT_SUSPEND)
2224                         ret = 1;
2225         }
2226
2227         return ret;
2228 }
2229
2230 /* Determine whether the device on a port is ready for a normal resume,
2231  * is ready for a reset-resume, or should be disconnected.
2232  */
2233 static int check_port_resume_type(struct usb_device *udev,
2234                 struct usb_hub *hub, int port1,
2235                 int status, unsigned portchange, unsigned portstatus)
2236 {
2237         /* Is the device still present? */
2238         if (status || port_is_suspended(hub, portstatus) ||
2239                         !port_is_power_on(hub, portstatus) ||
2240                         !(portstatus & USB_PORT_STAT_CONNECTION)) {
2241                 if (status >= 0)
2242                         status = -ENODEV;
2243         }
2244
2245         /* Can't do a normal resume if the port isn't enabled,
2246          * so try a reset-resume instead.
2247          */
2248         else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
2249                 if (udev->persist_enabled)
2250                         udev->reset_resume = 1;
2251                 else
2252                         status = -ENODEV;
2253         }
2254
2255         if (status) {
2256                 dev_dbg(hub->intfdev,
2257                                 "port %d status %04x.%04x after resume, %d\n",
2258                                 port1, portchange, portstatus, status);
2259         } else if (udev->reset_resume) {
2260
2261                 /* Late port handoff can set status-change bits */
2262                 if (portchange & USB_PORT_STAT_C_CONNECTION)
2263                         clear_port_feature(hub->hdev, port1,
2264                                         USB_PORT_FEAT_C_CONNECTION);
2265                 if (portchange & USB_PORT_STAT_C_ENABLE)
2266                         clear_port_feature(hub->hdev, port1,
2267                                         USB_PORT_FEAT_C_ENABLE);
2268         }
2269
2270         return status;
2271 }
2272
2273 #ifdef  CONFIG_USB_SUSPEND
2274
2275 /*
2276  * usb_port_suspend - suspend a usb device's upstream port
2277  * @udev: device that's no longer in active use, not a root hub
2278  * Context: must be able to sleep; device not locked; pm locks held
2279  *
2280  * Suspends a USB device that isn't in active use, conserving power.
2281  * Devices may wake out of a suspend, if anything important happens,
2282  * using the remote wakeup mechanism.  They may also be taken out of
2283  * suspend by the host, using usb_port_resume().  It's also routine
2284  * to disconnect devices while they are suspended.
2285  *
2286  * This only affects the USB hardware for a device; its interfaces
2287  * (and, for hubs, child devices) must already have been suspended.
2288  *
2289  * Selective port suspend reduces power; most suspended devices draw
2290  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
2291  * All devices below the suspended port are also suspended.
2292  *
2293  * Devices leave suspend state when the host wakes them up.  Some devices
2294  * also support "remote wakeup", where the device can activate the USB
2295  * tree above them to deliver data, such as a keypress or packet.  In
2296  * some cases, this wakes the USB host.
2297  *
2298  * Suspending OTG devices may trigger HNP, if that's been enabled
2299  * between a pair of dual-role devices.  That will change roles, such
2300  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
2301  *
2302  * Devices on USB hub ports have only one "suspend" state, corresponding
2303  * to ACPI D2, "may cause the device to lose some context".
2304  * State transitions include:
2305  *
2306  *   - suspend, resume ... when the VBUS power link stays live
2307  *   - suspend, disconnect ... VBUS lost
2308  *
2309  * Once VBUS drop breaks the circuit, the port it's using has to go through
2310  * normal re-enumeration procedures, starting with enabling VBUS power.
2311  * Other than re-initializing the hub (plug/unplug, except for root hubs),
2312  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
2313  * timer, no SRP, no requests through sysfs.
2314  *
2315  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
2316  * the root hub for their bus goes into global suspend ... so we don't
2317  * (falsely) update the device power state to say it suspended.
2318  *
2319  * Returns 0 on success, else negative errno.
2320  */
2321 int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2322 {
2323         struct usb_hub  *hub = hdev_to_hub(udev->parent);
2324         int             port1 = udev->portnum;
2325         int             status;
2326
2327         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
2328
2329         /* enable remote wakeup when appropriate; this lets the device
2330          * wake up the upstream hub (including maybe the root hub).
2331          *
2332          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
2333          * we don't explicitly enable it here.
2334          */
2335         if (udev->do_remote_wakeup) {
2336                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2337                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
2338                                 USB_DEVICE_REMOTE_WAKEUP, 0,
2339                                 NULL, 0,
2340                                 USB_CTRL_SET_TIMEOUT);
2341                 if (status) {
2342                         dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
2343                                         status);
2344                         /* bail if autosuspend is requested */
2345                         if (msg.event & PM_EVENT_AUTO)
2346                                 return status;
2347                 }
2348         }
2349
2350         /* see 7.1.7.6 */
2351         if (hub_is_superspeed(hub->hdev))
2352                 status = set_port_feature(hub->hdev,
2353                                 port1 | (USB_SS_PORT_LS_U3 << 3),
2354                                 USB_PORT_FEAT_LINK_STATE);
2355         else
2356                 status = set_port_feature(hub->hdev, port1,
2357                                                 USB_PORT_FEAT_SUSPEND);
2358         if (status) {
2359                 dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",
2360                                 port1, status);
2361                 /* paranoia:  "should not happen" */
2362                 if (udev->do_remote_wakeup)
2363                         (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2364                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
2365                                 USB_DEVICE_REMOTE_WAKEUP, 0,
2366                                 NULL, 0,
2367                                 USB_CTRL_SET_TIMEOUT);
2368
2369                 /* System sleep transitions should never fail */
2370                 if (!(msg.event & PM_EVENT_AUTO))
2371                         status = 0;
2372         } else {
2373                 /* device has up to 10 msec to fully suspend */
2374                 dev_dbg(&udev->dev, "usb %ssuspend\n",
2375                                 (msg.event & PM_EVENT_AUTO ? "auto-" : ""));
2376                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
2377                 msleep(10);
2378         }
2379         usb_mark_last_busy(hub->hdev);
2380         return status;
2381 }
2382
2383 /*
2384  * If the USB "suspend" state is in use (rather than "global suspend"),
2385  * many devices will be individually taken out of suspend state using
2386  * special "resume" signaling.  This routine kicks in shortly after
2387  * hardware resume signaling is finished, either because of selective
2388  * resume (by host) or remote wakeup (by device) ... now see what changed
2389  * in the tree that's rooted at this device.
2390  *
2391  * If @udev->reset_resume is set then the device is reset before the
2392  * status check is done.
2393  */
2394 static int finish_port_resume(struct usb_device *udev)
2395 {
2396         int     status = 0;
2397         u16     devstatus;
2398
2399         /* caller owns the udev device lock */
2400         dev_dbg(&udev->dev, "%s\n",
2401                 udev->reset_resume ? "finish reset-resume" : "finish resume");
2402
2403         /* usb ch9 identifies four variants of SUSPENDED, based on what
2404          * state the device resumes to.  Linux currently won't see the
2405          * first two on the host side; they'd be inside hub_port_init()
2406          * during many timeouts, but khubd can't suspend until later.
2407          */
2408         usb_set_device_state(udev, udev->actconfig
2409                         ? USB_STATE_CONFIGURED
2410                         : USB_STATE_ADDRESS);
2411
2412         /* 10.5.4.5 says not to reset a suspended port if the attached
2413          * device is enabled for remote wakeup.  Hence the reset
2414          * operation is carried out here, after the port has been
2415          * resumed.
2416          */
2417         if (udev->reset_resume)
2418  retry_reset_resume:
2419                 status = usb_reset_and_verify_device(udev);
2420
2421         /* 10.5.4.5 says be sure devices in the tree are still there.
2422          * For now let's assume the device didn't go crazy on resume,
2423          * and device drivers will know about any resume quirks.
2424          */
2425         if (status == 0) {
2426                 devstatus = 0;
2427                 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
2428                 if (status >= 0)
2429                         status = (status > 0 ? 0 : -ENODEV);
2430
2431                 /* If a normal resume failed, try doing a reset-resume */
2432                 if (status && !udev->reset_resume && udev->persist_enabled) {
2433                         dev_dbg(&udev->dev, "retry with reset-resume\n");
2434                         udev->reset_resume = 1;
2435                         goto retry_reset_resume;
2436                 }
2437         }
2438
2439         if (status) {
2440                 dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
2441                                 status);
2442         } else if (udev->actconfig) {
2443                 le16_to_cpus(&devstatus);
2444                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
2445                         status = usb_control_msg(udev,
2446                                         usb_sndctrlpipe(udev, 0),
2447                                         USB_REQ_CLEAR_FEATURE,
2448                                                 USB_RECIP_DEVICE,
2449                                         USB_DEVICE_REMOTE_WAKEUP, 0,
2450                                         NULL, 0,
2451                                         USB_CTRL_SET_TIMEOUT);
2452                         if (status)
2453                                 dev_dbg(&udev->dev,
2454                                         "disable remote wakeup, status %d\n",
2455                                         status);
2456                 }
2457                 status = 0;
2458         }
2459         return status;
2460 }
2461
2462 /*
2463  * usb_port_resume - re-activate a suspended usb device's upstream port
2464  * @udev: device to re-activate, not a root hub
2465  * Context: must be able to sleep; device not locked; pm locks held
2466  *
2467  * This will re-activate the suspended device, increasing power usage
2468  * while letting drivers communicate again with its endpoints.
2469  * USB resume explicitly guarantees that the power session between
2470  * the host and the device is the same as it was when the device
2471  * suspended.
2472  *
2473  * If @udev->reset_resume is set then this routine won't check that the
2474  * port is still enabled.  Furthermore, finish_port_resume() above will
2475  * reset @udev.  The end result is that a broken power session can be
2476  * recovered and @udev will appear to persist across a loss of VBUS power.
2477  *
2478  * For example, if a host controller doesn't maintain VBUS suspend current
2479  * during a system sleep or is reset when the system wakes up, all the USB
2480  * power sessions below it will be broken.  This is especially troublesome
2481  * for mass-storage devices containing mounted filesystems, since the
2482  * device will appear to have disconnected and all the memory mappings
2483  * to it will be lost.  Using the USB_PERSIST facility, the device can be
2484  * made to appear as if it had not disconnected.
2485  *
2486  * This facility can be dangerous.  Although usb_reset_and_verify_device() makes
2487  * every effort to insure that the same device is present after the
2488  * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
2489  * quite possible for a device to remain unaltered but its media to be
2490  * changed.  If the user replaces a flash memory card while the system is
2491  * asleep, he will have only himself to blame when the filesystem on the
2492  * new card is corrupted and the system crashes.
2493  *
2494  * Returns 0 on success, else negative errno.
2495  */
2496 int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2497 {
2498         struct usb_hub  *hub = hdev_to_hub(udev->parent);
2499         int             port1 = udev->portnum;
2500         int             status;
2501         u16             portchange, portstatus;
2502
2503         /* Skip the initial Clear-Suspend step for a remote wakeup */
2504         status = hub_port_status(hub, port1, &portstatus, &portchange);
2505         if (status == 0 && !port_is_suspended(hub, portstatus))
2506                 goto SuspendCleared;
2507
2508         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
2509
2510         set_bit(port1, hub->busy_bits);
2511
2512         /* see 7.1.7.7; affects power usage, but not budgeting */
2513         if (hub_is_superspeed(hub->hdev))
2514                 status = set_port_feature(hub->hdev,
2515                                 port1 | (USB_SS_PORT_LS_U0 << 3),
2516                                 USB_PORT_FEAT_LINK_STATE);
2517         else
2518                 status = clear_port_feature(hub->hdev,
2519                                 port1, USB_PORT_FEAT_SUSPEND);
2520         if (status) {
2521                 dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
2522                                 port1, status);
2523         } else {
2524                 /* drive resume for at least 20 msec */
2525                 dev_dbg(&udev->dev, "usb %sresume\n",
2526                                 (msg.event & PM_EVENT_AUTO ? "auto-" : ""));
2527                 msleep(25);
2528
2529                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
2530                  * stop resume signaling.  Then finish the resume
2531                  * sequence.
2532                  */
2533                 status = hub_port_status(hub, port1, &portstatus, &portchange);
2534
2535                 /* TRSMRCY = 10 msec */
2536                 msleep(10);
2537         }
2538
2539  SuspendCleared:
2540         if (status == 0) {
2541                 if (hub_is_superspeed(hub->hdev)) {
2542                         if (portchange & USB_PORT_STAT_C_LINK_STATE)
2543                                 clear_port_feature(hub->hdev, port1,
2544                                         USB_PORT_FEAT_C_PORT_LINK_STATE);
2545                 } else {
2546                         if (portchange & USB_PORT_STAT_C_SUSPEND)
2547                                 clear_port_feature(hub->hdev, port1,
2548                                                 USB_PORT_FEAT_C_SUSPEND);
2549                 }
2550         }
2551
2552         clear_bit(port1, hub->busy_bits);
2553
2554         status = check_port_resume_type(udev,
2555                         hub, port1, status, portchange, portstatus);
2556         if (status == 0)
2557                 status = finish_port_resume(udev);
2558         if (status < 0) {
2559                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2560                 hub_port_logical_disconnect(hub, port1);
2561         }
2562         return status;
2563 }
2564
2565 /* caller has locked udev */
2566 int usb_remote_wakeup(struct usb_device *udev)
2567 {
2568         int     status = 0;
2569
2570         if (udev->state == USB_STATE_SUSPENDED) {
2571                 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
2572                 status = usb_autoresume_device(udev);
2573                 if (status == 0) {
2574                         /* Let the drivers do their thing, then... */
2575                         usb_autosuspend_device(udev);
2576                 }
2577         }
2578         return status;
2579 }
2580
2581 #else   /* CONFIG_USB_SUSPEND */
2582
2583 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
2584
2585 int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2586 {
2587         return 0;
2588 }
2589
2590 /* However we may need to do a reset-resume */
2591
2592 int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2593 {
2594         struct usb_hub  *hub = hdev_to_hub(udev->parent);
2595         int             port1 = udev->portnum;
2596         int             status;
2597         u16             portchange, portstatus;
2598
2599         status = hub_port_status(hub, port1, &portstatus, &portchange);
2600         status = check_port_resume_type(udev,
2601                         hub, port1, status, portchange, portstatus);
2602
2603         if (status) {
2604                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2605                 hub_port_logical_disconnect(hub, port1);
2606         } else if (udev->reset_resume) {
2607                 dev_dbg(&udev->dev, "reset-resume\n");
2608                 status = usb_reset_and_verify_device(udev);
2609         }
2610         return status;
2611 }
2612
2613 #endif
2614
2615 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
2616 {
2617         struct usb_hub          *hub = usb_get_intfdata (intf);
2618         struct usb_device       *hdev = hub->hdev;
2619         unsigned                port1;
2620
2621         /* Warn if children aren't already suspended */
2622         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
2623                 struct usb_device       *udev;
2624
2625                 udev = hdev->children [port1-1];
2626                 if (udev && udev->can_submit) {
2627                         dev_warn(&intf->dev, "port %d nyet suspended\n", port1);
2628                         if (msg.event & PM_EVENT_AUTO)
2629                                 return -EBUSY;
2630                 }
2631         }
2632
2633         dev_dbg(&intf->dev, "%s\n", __func__);
2634
2635         /* stop khubd and related activity */
2636         hub_quiesce(hub, HUB_SUSPEND);
2637         return 0;
2638 }
2639
2640 static int hub_resume(struct usb_interface *intf)
2641 {
2642         struct usb_hub *hub = usb_get_intfdata(intf);
2643
2644         dev_dbg(&intf->dev, "%s\n", __func__);
2645         hub_activate(hub, HUB_RESUME);
2646         return 0;
2647 }
2648
2649 static int hub_reset_resume(struct usb_interface *intf)
2650 {
2651         struct usb_hub *hub = usb_get_intfdata(intf);
2652
2653         dev_dbg(&intf->dev, "%s\n", __func__);
2654         hub_activate(hub, HUB_RESET_RESUME);
2655         return 0;
2656 }
2657
2658 /**
2659  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
2660  * @rhdev: struct usb_device for the root hub
2661  *
2662  * The USB host controller driver calls this function when its root hub
2663  * is resumed and Vbus power has been interrupted or the controller
2664  * has been reset.  The routine marks @rhdev as having lost power.
2665  * When the hub driver is resumed it will take notice and carry out
2666  * power-session recovery for all the "USB-PERSIST"-enabled child devices;
2667  * the others will be disconnected.
2668  */
2669 void usb_root_hub_lost_power(struct usb_device *rhdev)
2670 {
2671         dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
2672         rhdev->reset_resume = 1;
2673 }
2674 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
2675
2676 #else   /* CONFIG_PM */
2677
2678 #define hub_suspend             NULL
2679 #define hub_resume              NULL
2680 #define hub_reset_resume        NULL
2681 #endif
2682
2683
2684 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2685  *
2686  * Between connect detection and reset signaling there must be a delay
2687  * of 100ms at least for debounce and power-settling.  The corresponding
2688  * timer shall restart whenever the downstream port detects a disconnect.
2689  * 
2690  * Apparently there are some bluetooth and irda-dongles and a number of
2691  * low-speed devices for which this debounce period may last over a second.
2692  * Not covered by the spec - but easy to deal with.
2693  *
2694  * This implementation uses a 1500ms total debounce timeout; if the
2695  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2696  * every 25ms for transient disconnects.  When the port status has been
2697  * unchanged for 100ms it returns the port status.
2698  */
2699 static int hub_port_debounce(struct usb_hub *hub, int port1)
2700 {
2701         int ret;
2702         int total_time, stable_time = 0;
2703         u16 portchange, portstatus;
2704         unsigned connection = 0xffff;
2705
2706         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2707                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2708                 if (ret < 0)
2709                         return ret;
2710
2711                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2712                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2713                         stable_time += HUB_DEBOUNCE_STEP;
2714                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2715                                 break;
2716                 } else {
2717                         stable_time = 0;
2718                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2719                 }
2720
2721                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2722                         clear_port_feature(hub->hdev, port1,
2723                                         USB_PORT_FEAT_C_CONNECTION);
2724                 }
2725
2726                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2727                         break;
2728                 msleep(HUB_DEBOUNCE_STEP);
2729         }
2730
2731         dev_dbg (hub->intfdev,
2732                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2733                 port1, total_time, stable_time, portstatus);
2734
2735         if (stable_time < HUB_DEBOUNCE_STABLE)
2736                 return -ETIMEDOUT;
2737         return portstatus;
2738 }
2739
2740 void usb_ep0_reinit(struct usb_device *udev)
2741 {
2742         usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
2743         usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
2744         usb_enable_endpoint(udev, &udev->ep0, true);
2745 }
2746 EXPORT_SYMBOL_GPL(usb_ep0_reinit);
2747
2748 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2749 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2750
2751 static int hub_set_address(struct usb_device *udev, int devnum)
2752 {
2753         int retval;
2754         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2755
2756         /*
2757          * The host controller will choose the device address,
2758          * instead of the core having chosen it earlier
2759          */
2760         if (!hcd->driver->address_device && devnum <= 1)
2761                 return -EINVAL;
2762         if (udev->state == USB_STATE_ADDRESS)
2763                 return 0;
2764         if (udev->state != USB_STATE_DEFAULT)
2765                 return -EINVAL;
2766         if (hcd->driver->address_device)
2767                 retval = hcd->driver->address_device(hcd, udev);
2768         else
2769                 retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2770                                 USB_REQ_SET_ADDRESS, 0, devnum, 0,
2771                                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2772         if (retval == 0) {
2773                 update_devnum(udev, devnum);
2774                 /* Device now using proper address. */
2775                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2776                 usb_ep0_reinit(udev);
2777         }
2778         return retval;
2779 }
2780
2781 /* Reset device, (re)assign address, get device descriptor.
2782  * Device connection must be stable, no more debouncing needed.
2783  * Returns device in USB_STATE_ADDRESS, except on error.
2784  *
2785  * If this is called for an already-existing device (as part of
2786  * usb_reset_and_verify_device), the caller must own the device lock.  For a
2787  * newly detected device that is not accessible through any global
2788  * pointers, it's not necessary to lock the device.
2789  */
2790 static int
2791 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2792                 int retry_counter)
2793 {
2794         static DEFINE_MUTEX(usb_address0_mutex);
2795
2796         struct usb_device       *hdev = hub->hdev;
2797         struct usb_hcd          *hcd = bus_to_hcd(hdev->bus);
2798         int                     i, j, retval;
2799         unsigned                delay = HUB_SHORT_RESET_TIME;
2800         enum usb_device_speed   oldspeed = udev->speed;
2801         char                    *speed, *type;
2802         int                     devnum = udev->devnum;
2803
2804         /* root hub ports have a slightly longer reset period
2805          * (from USB 2.0 spec, section 7.1.7.5)
2806          */
2807         if (!hdev->parent) {
2808                 delay = HUB_ROOT_RESET_TIME;
2809                 if (port1 == hdev->bus->otg_port)
2810                         hdev->bus->b_hnp_enable = 0;
2811         }
2812
2813         /* Some low speed devices have problems with the quick delay, so */
2814         /*  be a bit pessimistic with those devices. RHbug #23670 */
2815         if (oldspeed == USB_SPEED_LOW)
2816                 delay = HUB_LONG_RESET_TIME;
2817
2818         mutex_lock(&usb_address0_mutex);
2819
2820         /* Reset the device; full speed may morph to high speed */
2821         /* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
2822         retval = hub_port_reset(hub, port1, udev, delay);
2823         if (retval < 0)         /* error or disconnect */
2824                 goto fail;
2825         /* success, speed is known */
2826
2827         retval = -ENODEV;
2828
2829         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2830                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2831                 goto fail;
2832         }
2833         oldspeed = udev->speed;
2834
2835         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2836          * it's fixed size except for full speed devices.
2837          * For Wireless USB devices, ep0 max packet is always 512 (tho
2838          * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2839          */
2840         switch (udev->speed) {
2841         case USB_SPEED_SUPER:
2842         case USB_SPEED_WIRELESS:        /* fixed at 512 */
2843                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
2844                 break;
2845         case USB_SPEED_HIGH:            /* fixed at 64 */
2846                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
2847                 break;
2848         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2849                 /* to determine the ep0 maxpacket size, try to read
2850                  * the device descriptor to get bMaxPacketSize0 and
2851                  * then correct our initial guess.
2852                  */
2853                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
2854                 break;
2855         case USB_SPEED_LOW:             /* fixed at 8 */
2856                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
2857                 break;
2858         default:
2859                 goto fail;
2860         }
2861  
2862         type = "";
2863         switch (udev->speed) {
2864         case USB_SPEED_LOW:     speed = "low";  break;
2865         case USB_SPEED_FULL:    speed = "full"; break;
2866         case USB_SPEED_HIGH:    speed = "high"; break;
2867         case USB_SPEED_SUPER:
2868                                 speed = "super";
2869                                 break;
2870         case USB_SPEED_WIRELESS:
2871                                 speed = "variable";
2872                                 type = "Wireless ";
2873                                 break;
2874         default:                speed = "?";    break;
2875         }
2876         if (udev->speed != USB_SPEED_SUPER)
2877                 dev_info(&udev->dev,
2878                                 "%s %s speed %sUSB device number %d using %s\n",
2879                                 (udev->config) ? "reset" : "new", speed, type,
2880                                 devnum, udev->bus->controller->driver->name);
2881
2882         /* Set up TT records, if needed  */
2883         if (hdev->tt) {
2884                 udev->tt = hdev->tt;
2885                 udev->ttport = hdev->ttport;
2886         } else if (udev->speed != USB_SPEED_HIGH
2887                         && hdev->speed == USB_SPEED_HIGH) {
2888                 if (!hub->tt.hub) {
2889                         dev_err(&udev->dev, "parent hub has no TT\n");
2890                         retval = -EINVAL;
2891                         goto fail;
2892                 }
2893                 udev->tt = &hub->tt;
2894                 udev->ttport = port1;
2895         }
2896  
2897         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2898          * Because device hardware and firmware is sometimes buggy in
2899          * this area, and this is how Linux has done it for ages.
2900          * Change it cautiously.
2901          *
2902          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2903          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2904          * so it may help with some non-standards-compliant devices.
2905          * Otherwise we start with SET_ADDRESS and then try to read the
2906          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2907          * value.
2908          */
2909         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2910                 if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3)) {
2911                         struct usb_device_descriptor *buf;
2912                         int r = 0;
2913
2914 #define GET_DESCRIPTOR_BUFSIZE  64
2915                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2916                         if (!buf) {
2917                                 retval = -ENOMEM;
2918                                 continue;
2919                         }
2920
2921                         /* Retry on all errors; some devices are flakey.
2922                          * 255 is for WUSB devices, we actually need to use
2923                          * 512 (WUSB1.0[4.8.1]).
2924                          */
2925                         for (j = 0; j < 3; ++j) {
2926                                 buf->bMaxPacketSize0 = 0;
2927                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2928                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2929                                         USB_DT_DEVICE << 8, 0,
2930                                         buf, GET_DESCRIPTOR_BUFSIZE,
2931                                         initial_descriptor_timeout);
2932                                 switch (buf->bMaxPacketSize0) {
2933                                 case 8: case 16: case 32: case 64: case 255:
2934                                         if (buf->bDescriptorType ==
2935                                                         USB_DT_DEVICE) {
2936                                                 r = 0;
2937                                                 break;
2938                                         }
2939                                         /* FALL THROUGH */
2940                                 default:
2941                                         if (r == 0)
2942                                                 r = -EPROTO;
2943                                         break;
2944                                 }
2945                                 if (r == 0)
2946                                         break;
2947                         }
2948                         udev->descriptor.bMaxPacketSize0 =
2949                                         buf->bMaxPacketSize0;
2950                         kfree(buf);
2951
2952                         retval = hub_port_reset(hub, port1, udev, delay);
2953                         if (retval < 0)         /* error or disconnect */
2954                                 goto fail;
2955                         if (oldspeed != udev->speed) {
2956                                 dev_dbg(&udev->dev,
2957                                         "device reset changed speed!\n");
2958                                 retval = -ENODEV;
2959                                 goto fail;
2960                         }
2961                         if (r) {
2962                                 dev_err(&udev->dev,
2963                                         "device descriptor read/64, error %d\n",
2964                                         r);
2965                                 retval = -EMSGSIZE;
2966                                 continue;
2967                         }
2968 #undef GET_DESCRIPTOR_BUFSIZE
2969                 }
2970
2971                 /*
2972                  * If device is WUSB, we already assigned an
2973                  * unauthorized address in the Connect Ack sequence;
2974                  * authorization will assign the final address.
2975                  */
2976                 if (udev->wusb == 0) {
2977                         for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2978                                 retval = hub_set_address(udev, devnum);
2979                                 if (retval >= 0)
2980                                         break;
2981                                 msleep(200);
2982                         }
2983                         if (retval < 0) {
2984                                 dev_err(&udev->dev,
2985                                         "device not accepting address %d, error %d\n",
2986                                         devnum, retval);
2987                                 goto fail;
2988                         }
2989                         if (udev->speed == USB_SPEED_SUPER) {
2990                                 devnum = udev->devnum;
2991                                 dev_info(&udev->dev,
2992                                                 "%s SuperSpeed USB device number %d using %s\n",
2993                                                 (udev->config) ? "reset" : "new",
2994                                                 devnum, udev->bus->controller->driver->name);
2995                         }
2996
2997                         /* cope with hardware quirkiness:
2998                          *  - let SET_ADDRESS settle, some device hardware wants it
2999                          *  - read ep0 maxpacket even for high and low speed,
3000                          */
3001                         msleep(10);
3002                         if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3))
3003                                 break;
3004                 }
3005
3006                 retval = usb_get_device_descriptor(udev, 8);
3007                 if (retval < 8) {
3008                         dev_err(&udev->dev,
3009                                         "device descriptor read/8, error %d\n",
3010                                         retval);
3011                         if (retval >= 0)
3012                                 retval = -EMSGSIZE;
3013                 } else {
3014                         retval = 0;
3015                         break;
3016                 }
3017         }
3018         if (retval)
3019                 goto fail;
3020
3021         if (udev->descriptor.bMaxPacketSize0 == 0xff ||
3022                         udev->speed == USB_SPEED_SUPER)
3023                 i = 512;
3024         else
3025                 i = udev->descriptor.bMaxPacketSize0;
3026         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
3027                 if (udev->speed == USB_SPEED_LOW ||
3028                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
3029                         dev_err(&udev->dev, "Invalid ep0 maxpacket: %d\n", i);
3030                         retval = -EMSGSIZE;
3031                         goto fail;
3032                 }
3033                 if (udev->speed == USB_SPEED_FULL)
3034                         dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
3035                 else
3036                         dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i);
3037                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
3038                 usb_ep0_reinit(udev);