usb: retry reset if a device times out
[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 #include <linux/random.h>
28
29 #include <asm/uaccess.h>
30 #include <asm/byteorder.h>
31
32 #include "usb.h"
33
34 /* if we are in debug mode, always announce new devices */
35 #ifdef DEBUG
36 #ifndef CONFIG_USB_ANNOUNCE_NEW_DEVICES
37 #define CONFIG_USB_ANNOUNCE_NEW_DEVICES
38 #endif
39 #endif
40
41 struct usb_hub {
42         struct device           *intfdev;       /* the "interface" device */
43         struct usb_device       *hdev;
44         struct kref             kref;
45         struct urb              *urb;           /* for interrupt polling pipe */
46
47         /* buffer for urb ... with extra space in case of babble */
48         char                    (*buffer)[8];
49         union {
50                 struct usb_hub_status   hub;
51                 struct usb_port_status  port;
52         }                       *status;        /* buffer for status reports */
53         struct mutex            status_mutex;   /* for the status buffer */
54
55         int                     error;          /* last reported error */
56         int                     nerrors;        /* track consecutive errors */
57
58         struct list_head        event_list;     /* hubs w/data or errs ready */
59         unsigned long           event_bits[1];  /* status change bitmask */
60         unsigned long           change_bits[1]; /* ports with logical connect
61                                                         status change */
62         unsigned long           busy_bits[1];   /* ports being reset or
63                                                         resumed */
64         unsigned long           removed_bits[1]; /* ports with a "removed"
65                                                         device present */
66 #if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
67 #error event_bits[] is too short!
68 #endif
69
70         struct usb_hub_descriptor *descriptor;  /* class descriptor */
71         struct usb_tt           tt;             /* Transaction Translator */
72
73         unsigned                mA_per_port;    /* current for each child */
74
75         unsigned                limited_power:1;
76         unsigned                quiescing:1;
77         unsigned                disconnected:1;
78
79         unsigned                has_indicators:1;
80         u8                      indicator[USB_MAXCHILDREN];
81         struct delayed_work     leds;
82         struct delayed_work     init_work;
83         void                    **port_owners;
84 };
85
86 static inline int hub_is_superspeed(struct usb_device *hdev)
87 {
88         return (hdev->descriptor.bDeviceProtocol == 3);
89 }
90
91 /* Protect struct usb_device->state and ->children members
92  * Note: Both are also protected by ->dev.sem, except that ->state can
93  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
94 static DEFINE_SPINLOCK(device_state_lock);
95
96 /* khubd's worklist and its lock */
97 static DEFINE_SPINLOCK(hub_event_lock);
98 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
99
100 /* Wakes up khubd */
101 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
102
103 static struct task_struct *khubd_task;
104
105 /* cycle leds on hubs that aren't blinking for attention */
106 static int blinkenlights = 0;
107 module_param (blinkenlights, bool, S_IRUGO);
108 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
109
110 /*
111  * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
112  * 10 seconds to send reply for the initial 64-byte descriptor request.
113  */
114 /* define initial 64-byte descriptor request timeout in milliseconds */
115 static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
116 module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
117 MODULE_PARM_DESC(initial_descriptor_timeout,
118                 "initial 64-byte descriptor request timeout in milliseconds "
119                 "(default 5000 - 5.0 seconds)");
120
121 /*
122  * As of 2.6.10 we introduce a new USB device initialization scheme which
123  * closely resembles the way Windows works.  Hopefully it will be compatible
124  * with a wider range of devices than the old scheme.  However some previously
125  * working devices may start giving rise to "device not accepting address"
126  * errors; if that happens the user can try the old scheme by adjusting the
127  * following module parameters.
128  *
129  * For maximum flexibility there are two boolean parameters to control the
130  * hub driver's behavior.  On the first initialization attempt, if the
131  * "old_scheme_first" parameter is set then the old scheme will be used,
132  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
133  * is set, then the driver will make another attempt, using the other scheme.
134  */
135 static int old_scheme_first = 0;
136 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
137 MODULE_PARM_DESC(old_scheme_first,
138                  "start with the old device initialization scheme");
139
140 static int use_both_schemes = 1;
141 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
142 MODULE_PARM_DESC(use_both_schemes,
143                 "try the other device initialization scheme if the "
144                 "first one fails");
145
146 /* Mutual exclusion for EHCI CF initialization.  This interferes with
147  * port reset on some companion controllers.
148  */
149 DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
150 EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
151
152 #define HUB_DEBOUNCE_TIMEOUT    1500
153 #define HUB_DEBOUNCE_STEP         25
154 #define HUB_DEBOUNCE_STABLE      100
155
156 static void hub_release(struct kref *kref);
157 static int usb_reset_and_verify_device(struct usb_device *udev);
158
159 static inline char *portspeed(struct usb_hub *hub, int portstatus)
160 {
161         if (hub_is_superspeed(hub->hdev))
162                 return "5.0 Gb/s";
163         if (portstatus & USB_PORT_STAT_HIGH_SPEED)
164                 return "480 Mb/s";
165         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
166                 return "1.5 Mb/s";
167         else
168                 return "12 Mb/s";
169 }
170
171 /* Note that hdev or one of its children must be locked! */
172 static struct usb_hub *hdev_to_hub(struct usb_device *hdev)
173 {
174         if (!hdev || !hdev->actconfig)
175                 return NULL;
176         return usb_get_intfdata(hdev->actconfig->interface[0]);
177 }
178
179 /* USB 2.0 spec Section 11.24.4.5 */
180 static int get_hub_descriptor(struct usb_device *hdev, void *data)
181 {
182         int i, ret, size;
183         unsigned dtype;
184
185         if (hub_is_superspeed(hdev)) {
186                 dtype = USB_DT_SS_HUB;
187                 size = USB_DT_SS_HUB_SIZE;
188         } else {
189                 dtype = USB_DT_HUB;
190                 size = sizeof(struct usb_hub_descriptor);
191         }
192
193         for (i = 0; i < 3; i++) {
194                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
195                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
196                         dtype << 8, 0, data, size,
197                         USB_CTRL_GET_TIMEOUT);
198                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
199                         return ret;
200         }
201         return -EINVAL;
202 }
203
204 /*
205  * USB 2.0 spec Section 11.24.2.1
206  */
207 static int clear_hub_feature(struct usb_device *hdev, int feature)
208 {
209         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
210                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
211 }
212
213 /*
214  * USB 2.0 spec Section 11.24.2.2
215  */
216 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
217 {
218         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
219                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
220                 NULL, 0, 1000);
221 }
222
223 /*
224  * USB 2.0 spec Section 11.24.2.13
225  */
226 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
227 {
228         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
229                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
230                 NULL, 0, 1000);
231 }
232
233 /*
234  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
235  * for info about using port indicators
236  */
237 static void set_port_led(
238         struct usb_hub *hub,
239         int port1,
240         int selector
241 )
242 {
243         int status = set_port_feature(hub->hdev, (selector << 8) | port1,
244                         USB_PORT_FEAT_INDICATOR);
245         if (status < 0)
246                 dev_dbg (hub->intfdev,
247                         "port %d indicator %s status %d\n",
248                         port1,
249                         ({ char *s; switch (selector) {
250                         case HUB_LED_AMBER: s = "amber"; break;
251                         case HUB_LED_GREEN: s = "green"; break;
252                         case HUB_LED_OFF: s = "off"; break;
253                         case HUB_LED_AUTO: s = "auto"; break;
254                         default: s = "??"; break;
255                         }; s; }),
256                         status);
257 }
258
259 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
260
261 static void led_work (struct work_struct *work)
262 {
263         struct usb_hub          *hub =
264                 container_of(work, struct usb_hub, leds.work);
265         struct usb_device       *hdev = hub->hdev;
266         unsigned                i;
267         unsigned                changed = 0;
268         int                     cursor = -1;
269
270         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
271                 return;
272
273         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
274                 unsigned        selector, mode;
275
276                 /* 30%-50% duty cycle */
277
278                 switch (hub->indicator[i]) {
279                 /* cycle marker */
280                 case INDICATOR_CYCLE:
281                         cursor = i;
282                         selector = HUB_LED_AUTO;
283                         mode = INDICATOR_AUTO;
284                         break;
285                 /* blinking green = sw attention */
286                 case INDICATOR_GREEN_BLINK:
287                         selector = HUB_LED_GREEN;
288                         mode = INDICATOR_GREEN_BLINK_OFF;
289                         break;
290                 case INDICATOR_GREEN_BLINK_OFF:
291                         selector = HUB_LED_OFF;
292                         mode = INDICATOR_GREEN_BLINK;
293                         break;
294                 /* blinking amber = hw attention */
295                 case INDICATOR_AMBER_BLINK:
296                         selector = HUB_LED_AMBER;
297                         mode = INDICATOR_AMBER_BLINK_OFF;
298                         break;
299                 case INDICATOR_AMBER_BLINK_OFF:
300                         selector = HUB_LED_OFF;
301                         mode = INDICATOR_AMBER_BLINK;
302                         break;
303                 /* blink green/amber = reserved */
304                 case INDICATOR_ALT_BLINK:
305                         selector = HUB_LED_GREEN;
306                         mode = INDICATOR_ALT_BLINK_OFF;
307                         break;
308                 case INDICATOR_ALT_BLINK_OFF:
309                         selector = HUB_LED_AMBER;
310                         mode = INDICATOR_ALT_BLINK;
311                         break;
312                 default:
313                         continue;
314                 }
315                 if (selector != HUB_LED_AUTO)
316                         changed = 1;
317                 set_port_led(hub, i + 1, selector);
318                 hub->indicator[i] = mode;
319         }
320         if (!changed && blinkenlights) {
321                 cursor++;
322                 cursor %= hub->descriptor->bNbrPorts;
323                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
324                 hub->indicator[cursor] = INDICATOR_CYCLE;
325                 changed++;
326         }
327         if (changed)
328                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
329 }
330
331 /* use a short timeout for hub/port status fetches */
332 #define USB_STS_TIMEOUT         1000
333 #define USB_STS_RETRIES         5
334
335 /*
336  * USB 2.0 spec Section 11.24.2.6
337  */
338 static int get_hub_status(struct usb_device *hdev,
339                 struct usb_hub_status *data)
340 {
341         int i, status = -ETIMEDOUT;
342
343         for (i = 0; i < USB_STS_RETRIES &&
344                         (status == -ETIMEDOUT || status == -EPIPE); i++) {
345                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
346                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
347                         data, sizeof(*data), USB_STS_TIMEOUT);
348         }
349         return status;
350 }
351
352 /*
353  * USB 2.0 spec Section 11.24.2.7
354  */
355 static int get_port_status(struct usb_device *hdev, int port1,
356                 struct usb_port_status *data)
357 {
358         int i, status = -ETIMEDOUT;
359
360         for (i = 0; i < USB_STS_RETRIES &&
361                         (status == -ETIMEDOUT || status == -EPIPE); i++) {
362                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
363                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
364                         data, sizeof(*data), USB_STS_TIMEOUT);
365         }
366         return status;
367 }
368
369 static int hub_port_status(struct usb_hub *hub, int port1,
370                 u16 *status, u16 *change)
371 {
372         int ret;
373
374         mutex_lock(&hub->status_mutex);
375         ret = get_port_status(hub->hdev, port1, &hub->status->port);
376         if (ret < 4) {
377                 dev_err(hub->intfdev,
378                         "%s failed (err = %d)\n", __func__, ret);
379                 if (ret >= 0)
380                         ret = -EIO;
381         } else {
382                 *status = le16_to_cpu(hub->status->port.wPortStatus);
383                 *change = le16_to_cpu(hub->status->port.wPortChange);
384
385                 ret = 0;
386         }
387         mutex_unlock(&hub->status_mutex);
388         return ret;
389 }
390
391 static void kick_khubd(struct usb_hub *hub)
392 {
393         unsigned long   flags;
394
395         spin_lock_irqsave(&hub_event_lock, flags);
396         if (!hub->disconnected && list_empty(&hub->event_list)) {
397                 list_add_tail(&hub->event_list, &hub_event_list);
398
399                 /* Suppress autosuspend until khubd runs */
400                 usb_autopm_get_interface_no_resume(
401                                 to_usb_interface(hub->intfdev));
402                 wake_up(&khubd_wait);
403         }
404         spin_unlock_irqrestore(&hub_event_lock, flags);
405 }
406
407 void usb_kick_khubd(struct usb_device *hdev)
408 {
409         struct usb_hub *hub = hdev_to_hub(hdev);
410
411         if (hub)
412                 kick_khubd(hub);
413 }
414
415
416 /* completion function, fires on port status changes and various faults */
417 static void hub_irq(struct urb *urb)
418 {
419         struct usb_hub *hub = urb->context;
420         int status = urb->status;
421         unsigned i;
422         unsigned long bits;
423
424         switch (status) {
425         case -ENOENT:           /* synchronous unlink */
426         case -ECONNRESET:       /* async unlink */
427         case -ESHUTDOWN:        /* hardware going away */
428                 return;
429
430         default:                /* presumably an error */
431                 /* Cause a hub reset after 10 consecutive errors */
432                 dev_dbg (hub->intfdev, "transfer --> %d\n", status);
433                 if ((++hub->nerrors < 10) || hub->error)
434                         goto resubmit;
435                 hub->error = status;
436                 /* FALL THROUGH */
437
438         /* let khubd handle things */
439         case 0:                 /* we got data:  port status changed */
440                 bits = 0;
441                 for (i = 0; i < urb->actual_length; ++i)
442                         bits |= ((unsigned long) ((*hub->buffer)[i]))
443                                         << (i*8);
444                 hub->event_bits[0] = bits;
445                 break;
446         }
447
448         hub->nerrors = 0;
449
450         /* Something happened, let khubd figure it out */
451         kick_khubd(hub);
452
453 resubmit:
454         if (hub->quiescing)
455                 return;
456
457         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
458                         && status != -ENODEV && status != -EPERM)
459                 dev_err (hub->intfdev, "resubmit --> %d\n", status);
460 }
461
462 /* USB 2.0 spec Section 11.24.2.3 */
463 static inline int
464 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
465 {
466         /* Need to clear both directions for control ep */
467         if (((devinfo >> 11) & USB_ENDPOINT_XFERTYPE_MASK) ==
468                         USB_ENDPOINT_XFER_CONTROL) {
469                 int status = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
470                                 HUB_CLEAR_TT_BUFFER, USB_RT_PORT,
471                                 devinfo ^ 0x8000, tt, NULL, 0, 1000);
472                 if (status)
473                         return status;
474         }
475         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
476                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
477                                tt, NULL, 0, 1000);
478 }
479
480 /*
481  * enumeration blocks khubd for a long time. we use keventd instead, since
482  * long blocking there is the exception, not the rule.  accordingly, HCDs
483  * talking to TTs must queue control transfers (not just bulk and iso), so
484  * both can talk to the same hub concurrently.
485  */
486 static void hub_tt_work(struct work_struct *work)
487 {
488         struct usb_hub          *hub =
489                 container_of(work, struct usb_hub, tt.clear_work);
490         unsigned long           flags;
491         int                     limit = 100;
492
493         spin_lock_irqsave (&hub->tt.lock, flags);
494         while (!list_empty(&hub->tt.clear_list)) {
495                 struct list_head        *next;
496                 struct usb_tt_clear     *clear;
497                 struct usb_device       *hdev = hub->hdev;
498                 const struct hc_driver  *drv;
499                 int                     status;
500
501                 if (!hub->quiescing && --limit < 0)
502                         break;
503
504                 next = hub->tt.clear_list.next;
505                 clear = list_entry (next, struct usb_tt_clear, clear_list);
506                 list_del (&clear->clear_list);
507
508                 /* drop lock so HCD can concurrently report other TT errors */
509                 spin_unlock_irqrestore (&hub->tt.lock, flags);
510                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
511                 if (status)
512                         dev_err (&hdev->dev,
513                                 "clear tt %d (%04x) error %d\n",
514                                 clear->tt, clear->devinfo, status);
515
516                 /* Tell the HCD, even if the operation failed */
517                 drv = clear->hcd->driver;
518                 if (drv->clear_tt_buffer_complete)
519                         (drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
520
521                 kfree(clear);
522                 spin_lock_irqsave(&hub->tt.lock, flags);
523         }
524         spin_unlock_irqrestore (&hub->tt.lock, flags);
525 }
526
527 /**
528  * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
529  * @urb: an URB associated with the failed or incomplete split transaction
530  *
531  * High speed HCDs use this to tell the hub driver that some split control or
532  * bulk transaction failed in a way that requires clearing internal state of
533  * a transaction translator.  This is normally detected (and reported) from
534  * interrupt context.
535  *
536  * It may not be possible for that hub to handle additional full (or low)
537  * speed transactions until that state is fully cleared out.
538  */
539 int usb_hub_clear_tt_buffer(struct urb *urb)
540 {
541         struct usb_device       *udev = urb->dev;
542         int                     pipe = urb->pipe;
543         struct usb_tt           *tt = udev->tt;
544         unsigned long           flags;
545         struct usb_tt_clear     *clear;
546
547         /* we've got to cope with an arbitrary number of pending TT clears,
548          * since each TT has "at least two" buffers that can need it (and
549          * there can be many TTs per hub).  even if they're uncommon.
550          */
551         if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
552                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
553                 /* FIXME recover somehow ... RESET_TT? */
554                 return -ENOMEM;
555         }
556
557         /* info that CLEAR_TT_BUFFER needs */
558         clear->tt = tt->multi ? udev->ttport : 1;
559         clear->devinfo = usb_pipeendpoint (pipe);
560         clear->devinfo |= udev->devnum << 4;
561         clear->devinfo |= usb_pipecontrol (pipe)
562                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
563                         : (USB_ENDPOINT_XFER_BULK << 11);
564         if (usb_pipein (pipe))
565                 clear->devinfo |= 1 << 15;
566
567         /* info for completion callback */
568         clear->hcd = bus_to_hcd(udev->bus);
569         clear->ep = urb->ep;
570
571         /* tell keventd to clear state for this TT */
572         spin_lock_irqsave (&tt->lock, flags);
573         list_add_tail (&clear->clear_list, &tt->clear_list);
574         schedule_work(&tt->clear_work);
575         spin_unlock_irqrestore (&tt->lock, flags);
576         return 0;
577 }
578 EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
579
580 /* If do_delay is false, return the number of milliseconds the caller
581  * needs to delay.
582  */
583 static unsigned hub_power_on(struct usb_hub *hub, bool do_delay)
584 {
585         int port1;
586         unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
587         unsigned delay;
588         u16 wHubCharacteristics =
589                         le16_to_cpu(hub->descriptor->wHubCharacteristics);
590
591         /* Enable power on each port.  Some hubs have reserved values
592          * of LPSM (> 2) in their descriptors, even though they are
593          * USB 2.0 hubs.  Some hubs do not implement port-power switching
594          * but only emulate it.  In all cases, the ports won't work
595          * unless we send these messages to the hub.
596          */
597         if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
598                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
599         else
600                 dev_dbg(hub->intfdev, "trying to enable port power on "
601                                 "non-switchable hub\n");
602         for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
603                 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
604
605         /* Wait at least 100 msec for power to become stable */
606         delay = max(pgood_delay, (unsigned) 100);
607         if (do_delay)
608                 msleep(delay);
609         return delay;
610 }
611
612 static int hub_hub_status(struct usb_hub *hub,
613                 u16 *status, u16 *change)
614 {
615         int ret;
616
617         mutex_lock(&hub->status_mutex);
618         ret = get_hub_status(hub->hdev, &hub->status->hub);
619         if (ret < 0)
620                 dev_err (hub->intfdev,
621                         "%s failed (err = %d)\n", __func__, ret);
622         else {
623                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
624                 *change = le16_to_cpu(hub->status->hub.wHubChange); 
625                 ret = 0;
626         }
627         mutex_unlock(&hub->status_mutex);
628         return ret;
629 }
630
631 static int hub_set_port_link_state(struct usb_hub *hub, int port1,
632                         unsigned int link_status)
633 {
634         return set_port_feature(hub->hdev,
635                         port1 | (link_status << 3),
636                         USB_PORT_FEAT_LINK_STATE);
637 }
638
639 /*
640  * If USB 3.0 ports are placed into the Disabled state, they will no longer
641  * detect any device connects or disconnects.  This is generally not what the
642  * USB core wants, since it expects a disabled port to produce a port status
643  * change event when a new device connects.
644  *
645  * Instead, set the link state to Disabled, wait for the link to settle into
646  * that state, clear any change bits, and then put the port into the RxDetect
647  * state.
648  */
649 static int hub_usb3_port_disable(struct usb_hub *hub, int port1)
650 {
651         int ret;
652         int total_time;
653         u16 portchange, portstatus;
654
655         if (!hub_is_superspeed(hub->hdev))
656                 return -EINVAL;
657
658         ret = hub_port_status(hub, port1, &portstatus, &portchange);
659         if (ret < 0)
660                 return ret;
661
662         /*
663          * USB controller Advanced Micro Devices, Inc. [AMD] FCH USB XHCI
664          * Controller [1022:7814] will have spurious result making the following
665          * usb 3.0 device hotplugging route to the 2.0 root hub and recognized
666          * as high-speed device if we set the usb 3.0 port link state to
667          * Disabled. Since it's already in USB_SS_PORT_LS_RX_DETECT state, we
668          * check the state here to avoid the bug.
669          */
670         if ((portstatus & USB_PORT_STAT_LINK_STATE) ==
671                                 USB_SS_PORT_LS_RX_DETECT) {
672                 dev_dbg(hub->intfdev,
673                         "Not disabling port %d; link state is RxDetect\n",
674                         port1);
675                 return ret;
676         }
677
678         ret = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_SS_DISABLED);
679         if (ret) {
680                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
681                                 port1, ret);
682                 return ret;
683         }
684
685         /* Wait for the link to enter the disabled state. */
686         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
687                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
688                 if (ret < 0)
689                         return ret;
690
691                 if ((portstatus & USB_PORT_STAT_LINK_STATE) ==
692                                 USB_SS_PORT_LS_SS_DISABLED)
693                         break;
694                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
695                         break;
696                 msleep(HUB_DEBOUNCE_STEP);
697         }
698         if (total_time >= HUB_DEBOUNCE_TIMEOUT)
699                 dev_warn(hub->intfdev, "Could not disable port %d after %d ms\n",
700                                 port1, total_time);
701
702         return hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_RX_DETECT);
703 }
704
705 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
706 {
707         struct usb_device *hdev = hub->hdev;
708         int ret = 0;
709
710         if (hdev->children[port1-1] && set_state)
711                 usb_set_device_state(hdev->children[port1-1],
712                                 USB_STATE_NOTATTACHED);
713         if (!hub->error) {
714                 if (hub_is_superspeed(hub->hdev))
715                         ret = hub_usb3_port_disable(hub, port1);
716                 else
717                         ret = clear_port_feature(hdev, port1,
718                                         USB_PORT_FEAT_ENABLE);
719         }
720         if (ret)
721                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
722                                 port1, ret);
723         return ret;
724 }
725
726 /*
727  * Disable a port and mark a logical connect-change event, so that some
728  * time later khubd will disconnect() any existing usb_device on the port
729  * and will re-enumerate if there actually is a device attached.
730  */
731 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
732 {
733         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
734         hub_port_disable(hub, port1, 1);
735
736         /* FIXME let caller ask to power down the port:
737          *  - some devices won't enumerate without a VBUS power cycle
738          *  - SRP saves power that way
739          *  - ... new call, TBD ...
740          * That's easy if this hub can switch power per-port, and
741          * khubd reactivates the port later (timer, SRP, etc).
742          * Powerdown must be optional, because of reset/DFU.
743          */
744
745         set_bit(port1, hub->change_bits);
746         kick_khubd(hub);
747 }
748
749 /**
750  * usb_remove_device - disable a device's port on its parent hub
751  * @udev: device to be disabled and removed
752  * Context: @udev locked, must be able to sleep.
753  *
754  * After @udev's port has been disabled, khubd is notified and it will
755  * see that the device has been disconnected.  When the device is
756  * physically unplugged and something is plugged in, the events will
757  * be received and processed normally.
758  */
759 int usb_remove_device(struct usb_device *udev)
760 {
761         struct usb_hub *hub;
762         struct usb_interface *intf;
763
764         if (!udev->parent)      /* Can't remove a root hub */
765                 return -EINVAL;
766         hub = hdev_to_hub(udev->parent);
767         intf = to_usb_interface(hub->intfdev);
768
769         usb_autopm_get_interface(intf);
770         set_bit(udev->portnum, hub->removed_bits);
771         hub_port_logical_disconnect(hub, udev->portnum);
772         usb_autopm_put_interface(intf);
773         return 0;
774 }
775
776 enum hub_activation_type {
777         HUB_INIT, HUB_INIT2, HUB_INIT3,         /* INITs must come first */
778         HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
779 };
780
781 static void hub_init_func2(struct work_struct *ws);
782 static void hub_init_func3(struct work_struct *ws);
783
784 static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
785 {
786         struct usb_device *hdev = hub->hdev;
787         struct usb_hcd *hcd;
788         int ret;
789         int port1;
790         int status;
791         bool need_debounce_delay = false;
792         unsigned delay;
793
794         /* Continue a partial initialization */
795         if (type == HUB_INIT2 || type == HUB_INIT3) {
796                 device_lock(hub->intfdev);
797
798                 /* Was the hub disconnected while we were waiting? */
799                 if (hub->disconnected) {
800                         device_unlock(hub->intfdev);
801                         kref_put(&hub->kref, hub_release);
802                         return;
803                 }
804                 if (type == HUB_INIT2)
805                         goto init2;
806                 goto init3;
807         }
808         kref_get(&hub->kref);
809
810         /* The superspeed hub except for root hub has to use Hub Depth
811          * value as an offset into the route string to locate the bits
812          * it uses to determine the downstream port number. So hub driver
813          * should send a set hub depth request to superspeed hub after
814          * the superspeed hub is set configuration in initialization or
815          * reset procedure.
816          *
817          * After a resume, port power should still be on.
818          * For any other type of activation, turn it on.
819          */
820         if (type != HUB_RESUME) {
821                 if (hdev->parent && hub_is_superspeed(hdev)) {
822                         ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
823                                         HUB_SET_DEPTH, USB_RT_HUB,
824                                         hdev->level - 1, 0, NULL, 0,
825                                         USB_CTRL_SET_TIMEOUT);
826                         if (ret < 0)
827                                 dev_err(hub->intfdev,
828                                                 "set hub depth failed\n");
829                 }
830
831                 /* Speed up system boot by using a delayed_work for the
832                  * hub's initial power-up delays.  This is pretty awkward
833                  * and the implementation looks like a home-brewed sort of
834                  * setjmp/longjmp, but it saves at least 100 ms for each
835                  * root hub (assuming usbcore is compiled into the kernel
836                  * rather than as a module).  It adds up.
837                  *
838                  * This can't be done for HUB_RESUME or HUB_RESET_RESUME
839                  * because for those activation types the ports have to be
840                  * operational when we return.  In theory this could be done
841                  * for HUB_POST_RESET, but it's easier not to.
842                  */
843                 if (type == HUB_INIT) {
844                         delay = hub_power_on(hub, false);
845                         PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func2);
846                         schedule_delayed_work(&hub->init_work,
847                                         msecs_to_jiffies(delay));
848
849                         /* Suppress autosuspend until init is done */
850                         usb_autopm_get_interface_no_resume(
851                                         to_usb_interface(hub->intfdev));
852                         return;         /* Continues at init2: below */
853                 } else if (type == HUB_RESET_RESUME) {
854                         /* The internal host controller state for the hub device
855                          * may be gone after a host power loss on system resume.
856                          * Update the device's info so the HW knows it's a hub.
857                          */
858                         hcd = bus_to_hcd(hdev->bus);
859                         if (hcd->driver->update_hub_device) {
860                                 ret = hcd->driver->update_hub_device(hcd, hdev,
861                                                 &hub->tt, GFP_NOIO);
862                                 if (ret < 0) {
863                                         dev_err(hub->intfdev, "Host not "
864                                                         "accepting hub info "
865                                                         "update.\n");
866                                         dev_err(hub->intfdev, "LS/FS devices "
867                                                         "and hubs may not work "
868                                                         "under this hub\n.");
869                                 }
870                         }
871                         hub_power_on(hub, true);
872                 } else {
873                         hub_power_on(hub, true);
874                 }
875         }
876  init2:
877
878         /* Check each port and set hub->change_bits to let khubd know
879          * which ports need attention.
880          */
881         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
882                 struct usb_device *udev = hdev->children[port1-1];
883                 u16 portstatus, portchange;
884
885                 portstatus = portchange = 0;
886                 status = hub_port_status(hub, port1, &portstatus, &portchange);
887                 if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
888                         dev_dbg(hub->intfdev,
889                                         "port %d: status %04x change %04x\n",
890                                         port1, portstatus, portchange);
891
892                 /* After anything other than HUB_RESUME (i.e., initialization
893                  * or any sort of reset), every port should be disabled.
894                  * Unconnected ports should likewise be disabled (paranoia),
895                  * and so should ports for which we have no usb_device.
896                  */
897                 if ((portstatus & USB_PORT_STAT_ENABLE) && (
898                                 type != HUB_RESUME ||
899                                 !(portstatus & USB_PORT_STAT_CONNECTION) ||
900                                 !udev ||
901                                 udev->state == USB_STATE_NOTATTACHED)) {
902                         /*
903                          * USB3 protocol ports will automatically transition
904                          * to Enabled state when detect an USB3.0 device attach.
905                          * Do not disable USB3 protocol ports.
906                          */
907                         if (!hub_is_superspeed(hdev)) {
908                                 clear_port_feature(hdev, port1,
909                                                    USB_PORT_FEAT_ENABLE);
910                                 portstatus &= ~USB_PORT_STAT_ENABLE;
911                         } else {
912                                 /* Pretend that power was lost for USB3 devs */
913                                 portstatus &= ~USB_PORT_STAT_ENABLE;
914                         }
915                 }
916
917                 /* Clear status-change flags; we'll debounce later */
918                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
919                         need_debounce_delay = true;
920                         clear_port_feature(hub->hdev, port1,
921                                         USB_PORT_FEAT_C_CONNECTION);
922                 }
923                 if (portchange & USB_PORT_STAT_C_ENABLE) {
924                         need_debounce_delay = true;
925                         clear_port_feature(hub->hdev, port1,
926                                         USB_PORT_FEAT_C_ENABLE);
927                 }
928                 if (portchange & USB_PORT_STAT_C_LINK_STATE) {
929                         need_debounce_delay = true;
930                         clear_port_feature(hub->hdev, port1,
931                                         USB_PORT_FEAT_C_PORT_LINK_STATE);
932                 }
933                 if (portchange & USB_PORT_STAT_C_RESET) {
934                         need_debounce_delay = true;
935                         clear_port_feature(hub->hdev, port1,
936                                         USB_PORT_FEAT_C_RESET);
937                 }
938
939                 if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
940                                 hub_is_superspeed(hub->hdev)) {
941                         need_debounce_delay = true;
942                         clear_port_feature(hub->hdev, port1,
943                                         USB_PORT_FEAT_C_BH_PORT_RESET);
944                 }
945                 /* We can forget about a "removed" device when there's a
946                  * physical disconnect or the connect status changes.
947                  */
948                 if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
949                                 (portchange & USB_PORT_STAT_C_CONNECTION))
950                         clear_bit(port1, hub->removed_bits);
951
952                 if (!udev || udev->state == USB_STATE_NOTATTACHED) {
953                         /* Tell khubd to disconnect the device or
954                          * check for a new connection
955                          */
956                         if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
957                                 set_bit(port1, hub->change_bits);
958
959                 } else if (portstatus & USB_PORT_STAT_ENABLE) {
960                         /* The power session apparently survived the resume.
961                          * If there was an overcurrent or suspend change
962                          * (i.e., remote wakeup request), have khubd
963                          * take care of it.
964                          */
965                         if (portchange)
966                                 set_bit(port1, hub->change_bits);
967
968                 } else if (udev->persist_enabled) {
969 #ifdef CONFIG_PM
970                         udev->reset_resume = 1;
971 #endif
972                         set_bit(port1, hub->change_bits);
973
974                 } else {
975                         /* The power session is gone; tell khubd */
976                         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
977                         set_bit(port1, hub->change_bits);
978                 }
979         }
980
981         /* If no port-status-change flags were set, we don't need any
982          * debouncing.  If flags were set we can try to debounce the
983          * ports all at once right now, instead of letting khubd do them
984          * one at a time later on.
985          *
986          * If any port-status changes do occur during this delay, khubd
987          * will see them later and handle them normally.
988          */
989         if (need_debounce_delay) {
990                 delay = HUB_DEBOUNCE_STABLE;
991
992                 /* Don't do a long sleep inside a workqueue routine */
993                 if (type == HUB_INIT2) {
994                         PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func3);
995                         schedule_delayed_work(&hub->init_work,
996                                         msecs_to_jiffies(delay));
997                         device_unlock(hub->intfdev);
998                         return;         /* Continues at init3: below */
999                 } else {
1000                         msleep(delay);
1001                 }
1002         }
1003  init3:
1004         hub->quiescing = 0;
1005
1006         status = usb_submit_urb(hub->urb, GFP_NOIO);
1007         if (status < 0)
1008                 dev_err(hub->intfdev, "activate --> %d\n", status);
1009         if (hub->has_indicators && blinkenlights)
1010                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
1011
1012         /* Scan all ports that need attention */
1013         kick_khubd(hub);
1014
1015         /* Allow autosuspend if it was suppressed */
1016         if (type <= HUB_INIT3)
1017                 usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
1018
1019         if (type == HUB_INIT2 || type == HUB_INIT3)
1020                 device_unlock(hub->intfdev);
1021
1022         kref_put(&hub->kref, hub_release);
1023 }
1024
1025 /* Implement the continuations for the delays above */
1026 static void hub_init_func2(struct work_struct *ws)
1027 {
1028         struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1029
1030         hub_activate(hub, HUB_INIT2);
1031 }
1032
1033 static void hub_init_func3(struct work_struct *ws)
1034 {
1035         struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1036
1037         hub_activate(hub, HUB_INIT3);
1038 }
1039
1040 enum hub_quiescing_type {
1041         HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
1042 };
1043
1044 static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
1045 {
1046         struct usb_device *hdev = hub->hdev;
1047         int i;
1048
1049         cancel_delayed_work_sync(&hub->init_work);
1050
1051         /* khubd and related activity won't re-trigger */
1052         hub->quiescing = 1;
1053
1054         if (type != HUB_SUSPEND) {
1055                 /* Disconnect all the children */
1056                 for (i = 0; i < hdev->maxchild; ++i) {
1057                         if (hdev->children[i])
1058                                 usb_disconnect(&hdev->children[i]);
1059                 }
1060         }
1061
1062         /* Stop khubd and related activity */
1063         usb_kill_urb(hub->urb);
1064         if (hub->has_indicators)
1065                 cancel_delayed_work_sync(&hub->leds);
1066         if (hub->tt.hub)
1067                 flush_work_sync(&hub->tt.clear_work);
1068 }
1069
1070 /* caller has locked the hub device */
1071 static int hub_pre_reset(struct usb_interface *intf)
1072 {
1073         struct usb_hub *hub = usb_get_intfdata(intf);
1074
1075         hub_quiesce(hub, HUB_PRE_RESET);
1076         return 0;
1077 }
1078
1079 /* caller has locked the hub device */
1080 static int hub_post_reset(struct usb_interface *intf)
1081 {
1082         struct usb_hub *hub = usb_get_intfdata(intf);
1083
1084         hub_activate(hub, HUB_POST_RESET);
1085         return 0;
1086 }
1087
1088 static int hub_configure(struct usb_hub *hub,
1089         struct usb_endpoint_descriptor *endpoint)
1090 {
1091         struct usb_hcd *hcd;
1092         struct usb_device *hdev = hub->hdev;
1093         struct device *hub_dev = hub->intfdev;
1094         u16 hubstatus, hubchange;
1095         u16 wHubCharacteristics;
1096         unsigned int pipe;
1097         int maxp, ret;
1098         char *message = "out of memory";
1099
1100         hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
1101         if (!hub->buffer) {
1102                 ret = -ENOMEM;
1103                 goto fail;
1104         }
1105
1106         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
1107         if (!hub->status) {
1108                 ret = -ENOMEM;
1109                 goto fail;
1110         }
1111         mutex_init(&hub->status_mutex);
1112
1113         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
1114         if (!hub->descriptor) {
1115                 ret = -ENOMEM;
1116                 goto fail;
1117         }
1118
1119         /* Request the entire hub descriptor.
1120          * hub->descriptor can handle USB_MAXCHILDREN ports,
1121          * but the hub can/will return fewer bytes here.
1122          */
1123         ret = get_hub_descriptor(hdev, hub->descriptor);
1124         if (ret < 0) {
1125                 message = "can't read hub descriptor";
1126                 goto fail;
1127         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
1128                 message = "hub has too many ports!";
1129                 ret = -ENODEV;
1130                 goto fail;
1131         }
1132
1133         hdev->maxchild = hub->descriptor->bNbrPorts;
1134         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
1135                 (hdev->maxchild == 1) ? "" : "s");
1136
1137         hub->port_owners = kzalloc(hdev->maxchild * sizeof(void *), GFP_KERNEL);
1138         if (!hub->port_owners) {
1139                 ret = -ENOMEM;
1140                 goto fail;
1141         }
1142
1143         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1144
1145         /* FIXME for USB 3.0, skip for now */
1146         if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
1147                         !(hub_is_superspeed(hdev))) {
1148                 int     i;
1149                 char    portstr [USB_MAXCHILDREN + 1];
1150
1151                 for (i = 0; i < hdev->maxchild; i++)
1152                         portstr[i] = hub->descriptor->u.hs.DeviceRemovable
1153                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
1154                                 ? 'F' : 'R';
1155                 portstr[hdev->maxchild] = 0;
1156                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
1157         } else
1158                 dev_dbg(hub_dev, "standalone hub\n");
1159
1160         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1161                 case 0x00:
1162                         dev_dbg(hub_dev, "ganged power switching\n");
1163                         break;
1164                 case 0x01:
1165                         dev_dbg(hub_dev, "individual port power switching\n");
1166                         break;
1167                 case 0x02:
1168                 case 0x03:
1169                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
1170                         break;
1171         }
1172
1173         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1174                 case 0x00:
1175                         dev_dbg(hub_dev, "global over-current protection\n");
1176                         break;
1177                 case 0x08:
1178                         dev_dbg(hub_dev, "individual port over-current protection\n");
1179                         break;
1180                 case 0x10:
1181                 case 0x18:
1182                         dev_dbg(hub_dev, "no over-current protection\n");
1183                         break;
1184         }
1185
1186         spin_lock_init (&hub->tt.lock);
1187         INIT_LIST_HEAD (&hub->tt.clear_list);
1188         INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1189         switch (hdev->descriptor.bDeviceProtocol) {
1190                 case 0:
1191                         break;
1192                 case 1:
1193                         dev_dbg(hub_dev, "Single TT\n");
1194                         hub->tt.hub = hdev;
1195                         break;
1196                 case 2:
1197                         ret = usb_set_interface(hdev, 0, 1);
1198                         if (ret == 0) {
1199                                 dev_dbg(hub_dev, "TT per port\n");
1200                                 hub->tt.multi = 1;
1201                         } else
1202                                 dev_err(hub_dev, "Using single TT (err %d)\n",
1203                                         ret);
1204                         hub->tt.hub = hdev;
1205                         break;
1206                 case 3:
1207                         /* USB 3.0 hubs don't have a TT */
1208                         break;
1209                 default:
1210                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1211                                 hdev->descriptor.bDeviceProtocol);
1212                         break;
1213         }
1214
1215         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1216         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1217                 case HUB_TTTT_8_BITS:
1218                         if (hdev->descriptor.bDeviceProtocol != 0) {
1219                                 hub->tt.think_time = 666;
1220                                 dev_dbg(hub_dev, "TT requires at most %d "
1221                                                 "FS bit times (%d ns)\n",
1222                                         8, hub->tt.think_time);
1223                         }
1224                         break;
1225                 case HUB_TTTT_16_BITS:
1226                         hub->tt.think_time = 666 * 2;
1227                         dev_dbg(hub_dev, "TT requires at most %d "
1228                                         "FS bit times (%d ns)\n",
1229                                 16, hub->tt.think_time);
1230                         break;
1231                 case HUB_TTTT_24_BITS:
1232                         hub->tt.think_time = 666 * 3;
1233                         dev_dbg(hub_dev, "TT requires at most %d "
1234                                         "FS bit times (%d ns)\n",
1235                                 24, hub->tt.think_time);
1236                         break;
1237                 case HUB_TTTT_32_BITS:
1238                         hub->tt.think_time = 666 * 4;
1239                         dev_dbg(hub_dev, "TT requires at most %d "
1240                                         "FS bit times (%d ns)\n",
1241                                 32, hub->tt.think_time);
1242                         break;
1243         }
1244
1245         /* probe() zeroes hub->indicator[] */
1246         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1247                 hub->has_indicators = 1;
1248                 dev_dbg(hub_dev, "Port indicators are supported\n");
1249         }
1250
1251         dev_dbg(hub_dev, "power on to power good time: %dms\n",
1252                 hub->descriptor->bPwrOn2PwrGood * 2);
1253
1254         /* power budgeting mostly matters with bus-powered hubs,
1255          * and battery-powered root hubs (may provide just 8 mA).
1256          */
1257         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1258         if (ret < 2) {
1259                 message = "can't get hub status";
1260                 goto fail;
1261         }
1262         le16_to_cpus(&hubstatus);
1263         if (hdev == hdev->bus->root_hub) {
1264                 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
1265                         hub->mA_per_port = 500;
1266                 else {
1267                         hub->mA_per_port = hdev->bus_mA;
1268                         hub->limited_power = 1;
1269                 }
1270         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1271                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1272                         hub->descriptor->bHubContrCurrent);
1273                 hub->limited_power = 1;
1274                 if (hdev->maxchild > 0) {
1275                         int remaining = hdev->bus_mA -
1276                                         hub->descriptor->bHubContrCurrent;
1277
1278                         if (remaining < hdev->maxchild * 100)
1279                                 dev_warn(hub_dev,
1280                                         "insufficient power available "
1281                                         "to use all downstream ports\n");
1282                         hub->mA_per_port = 100;         /* 7.2.1.1 */
1283                 }
1284         } else {        /* Self-powered external hub */
1285                 /* FIXME: What about battery-powered external hubs that
1286                  * provide less current per port? */
1287                 hub->mA_per_port = 500;
1288         }
1289         if (hub->mA_per_port < 500)
1290                 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1291                                 hub->mA_per_port);
1292
1293         /* Update the HCD's internal representation of this hub before khubd
1294          * starts getting port status changes for devices under the hub.
1295          */
1296         hcd = bus_to_hcd(hdev->bus);
1297         if (hcd->driver->update_hub_device) {
1298                 ret = hcd->driver->update_hub_device(hcd, hdev,
1299                                 &hub->tt, GFP_KERNEL);
1300                 if (ret < 0) {
1301                         message = "can't update HCD hub info";
1302                         goto fail;
1303                 }
1304         }
1305
1306         ret = hub_hub_status(hub, &hubstatus, &hubchange);
1307         if (ret < 0) {
1308                 message = "can't get hub status";
1309                 goto fail;
1310         }
1311
1312         /* local power status reports aren't always correct */
1313         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1314                 dev_dbg(hub_dev, "local power source is %s\n",
1315                         (hubstatus & HUB_STATUS_LOCAL_POWER)
1316                         ? "lost (inactive)" : "good");
1317
1318         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1319                 dev_dbg(hub_dev, "%sover-current condition exists\n",
1320                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1321
1322         /* set up the interrupt endpoint
1323          * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1324          * bytes as USB2.0[11.12.3] says because some hubs are known
1325          * to send more data (and thus cause overflow). For root hubs,
1326          * maxpktsize is defined in hcd.c's fake endpoint descriptors
1327          * to be big enough for at least USB_MAXCHILDREN ports. */
1328         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1329         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
1330
1331         if (maxp > sizeof(*hub->buffer))
1332                 maxp = sizeof(*hub->buffer);
1333
1334         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1335         if (!hub->urb) {
1336                 ret = -ENOMEM;
1337                 goto fail;
1338         }
1339
1340         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1341                 hub, endpoint->bInterval);
1342
1343         /* maybe cycle the hub leds */
1344         if (hub->has_indicators && blinkenlights)
1345                 hub->indicator [0] = INDICATOR_CYCLE;
1346
1347         hub_activate(hub, HUB_INIT);
1348         return 0;
1349
1350 fail:
1351         dev_err (hub_dev, "config failed, %s (err %d)\n",
1352                         message, ret);
1353         /* hub_disconnect() frees urb and descriptor */
1354         return ret;
1355 }
1356
1357 static void hub_release(struct kref *kref)
1358 {
1359         struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1360
1361         usb_put_intf(to_usb_interface(hub->intfdev));
1362         kfree(hub);
1363 }
1364
1365 static unsigned highspeed_hubs;
1366
1367 static void hub_disconnect(struct usb_interface *intf)
1368 {
1369         struct usb_hub *hub = usb_get_intfdata (intf);
1370
1371         /* Take the hub off the event list and don't let it be added again */
1372         spin_lock_irq(&hub_event_lock);
1373         if (!list_empty(&hub->event_list)) {
1374                 list_del_init(&hub->event_list);
1375                 usb_autopm_put_interface_no_suspend(intf);
1376         }
1377         hub->disconnected = 1;
1378         spin_unlock_irq(&hub_event_lock);
1379
1380         /* Disconnect all children and quiesce the hub */
1381         hub->error = 0;
1382         hub_quiesce(hub, HUB_DISCONNECT);
1383
1384         usb_set_intfdata (intf, NULL);
1385         hub->hdev->maxchild = 0;
1386
1387         if (hub->hdev->speed == USB_SPEED_HIGH)
1388                 highspeed_hubs--;
1389
1390         usb_free_urb(hub->urb);
1391         kfree(hub->port_owners);
1392         kfree(hub->descriptor);
1393         kfree(hub->status);
1394         kfree(hub->buffer);
1395
1396         kref_put(&hub->kref, hub_release);
1397 }
1398
1399 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1400 {
1401         struct usb_host_interface *desc;
1402         struct usb_endpoint_descriptor *endpoint;
1403         struct usb_device *hdev;
1404         struct usb_hub *hub;
1405
1406         desc = intf->cur_altsetting;
1407         hdev = interface_to_usbdev(intf);
1408
1409         /*
1410          * Hubs have proper suspend/resume support, except for root hubs
1411          * where the controller driver doesn't have bus_suspend and
1412          * bus_resume methods.  Also, USB 3.0 device suspend is
1413          * different from USB 2.0/1.1 device suspend, and unfortunately we
1414          * don't support it yet.  So leave autosuspend disabled for USB 3.0
1415          * external hubs for now.  Enable autosuspend for USB 3.0 roothubs,
1416          * since that isn't a "real" hub.
1417          */
1418         if (hdev->parent) {             /* normal device */
1419                 if (!hub_is_superspeed(hdev))
1420                         usb_enable_autosuspend(hdev);
1421         } else {                        /* root hub */
1422                 const struct hc_driver *drv = bus_to_hcd(hdev->bus)->driver;
1423
1424                 if (drv->bus_suspend && drv->bus_resume)
1425                         usb_enable_autosuspend(hdev);
1426         }
1427
1428         if (hdev->level == MAX_TOPO_LEVEL) {
1429                 dev_err(&intf->dev,
1430                         "Unsupported bus topology: hub nested too deep\n");
1431                 return -E2BIG;
1432         }
1433
1434 #ifdef  CONFIG_USB_OTG_BLACKLIST_HUB
1435         if (hdev->parent) {
1436                 dev_warn(&intf->dev, "ignoring external hub\n");
1437                 return -ENODEV;
1438         }
1439 #endif
1440
1441         /* Some hubs have a subclass of 1, which AFAICT according to the */
1442         /*  specs is not defined, but it works */
1443         if ((desc->desc.bInterfaceSubClass != 0) &&
1444             (desc->desc.bInterfaceSubClass != 1)) {
1445 descriptor_error:
1446                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
1447                 return -EIO;
1448         }
1449
1450         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
1451         if (desc->desc.bNumEndpoints != 1)
1452                 goto descriptor_error;
1453
1454         endpoint = &desc->endpoint[0].desc;
1455
1456         /* If it's not an interrupt in endpoint, we'd better punt! */
1457         if (!usb_endpoint_is_int_in(endpoint))
1458                 goto descriptor_error;
1459
1460         /* We found a hub */
1461         dev_info (&intf->dev, "USB hub found\n");
1462
1463         hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1464         if (!hub) {
1465                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
1466                 return -ENOMEM;
1467         }
1468
1469         kref_init(&hub->kref);
1470         INIT_LIST_HEAD(&hub->event_list);
1471         hub->intfdev = &intf->dev;
1472         hub->hdev = hdev;
1473         INIT_DELAYED_WORK(&hub->leds, led_work);
1474         INIT_DELAYED_WORK(&hub->init_work, NULL);
1475         usb_get_intf(intf);
1476
1477         usb_set_intfdata (intf, hub);
1478         intf->needs_remote_wakeup = 1;
1479
1480         if (hdev->speed == USB_SPEED_HIGH)
1481                 highspeed_hubs++;
1482
1483         if (hub_configure(hub, endpoint) >= 0)
1484                 return 0;
1485
1486         hub_disconnect (intf);
1487         return -ENODEV;
1488 }
1489
1490 /* No BKL needed */
1491 static int
1492 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1493 {
1494         struct usb_device *hdev = interface_to_usbdev (intf);
1495
1496         /* assert ifno == 0 (part of hub spec) */
1497         switch (code) {
1498         case USBDEVFS_HUB_PORTINFO: {
1499                 struct usbdevfs_hub_portinfo *info = user_data;
1500                 int i;
1501
1502                 spin_lock_irq(&device_state_lock);
1503                 if (hdev->devnum <= 0)
1504                         info->nports = 0;
1505                 else {
1506                         info->nports = hdev->maxchild;
1507                         for (i = 0; i < info->nports; i++) {
1508                                 if (hdev->children[i] == NULL)
1509                                         info->port[i] = 0;
1510                                 else
1511                                         info->port[i] =
1512                                                 hdev->children[i]->devnum;
1513                         }
1514                 }
1515                 spin_unlock_irq(&device_state_lock);
1516
1517                 return info->nports + 1;
1518                 }
1519
1520         default:
1521                 return -ENOSYS;
1522         }
1523 }
1524
1525 /*
1526  * Allow user programs to claim ports on a hub.  When a device is attached
1527  * to one of these "claimed" ports, the program will "own" the device.
1528  */
1529 static int find_port_owner(struct usb_device *hdev, unsigned port1,
1530                 void ***ppowner)
1531 {
1532         if (hdev->state == USB_STATE_NOTATTACHED)
1533                 return -ENODEV;
1534         if (port1 == 0 || port1 > hdev->maxchild)
1535                 return -EINVAL;
1536
1537         /* This assumes that devices not managed by the hub driver
1538          * will always have maxchild equal to 0.
1539          */
1540         *ppowner = &(hdev_to_hub(hdev)->port_owners[port1 - 1]);
1541         return 0;
1542 }
1543
1544 /* In the following three functions, the caller must hold hdev's lock */
1545 int usb_hub_claim_port(struct usb_device *hdev, unsigned port1, void *owner)
1546 {
1547         int rc;
1548         void **powner;
1549
1550         rc = find_port_owner(hdev, port1, &powner);
1551         if (rc)
1552                 return rc;
1553         if (*powner)
1554                 return -EBUSY;
1555         *powner = owner;
1556         return rc;
1557 }
1558
1559 int usb_hub_release_port(struct usb_device *hdev, unsigned port1, void *owner)
1560 {
1561         int rc;
1562         void **powner;
1563
1564         rc = find_port_owner(hdev, port1, &powner);
1565         if (rc)
1566                 return rc;
1567         if (*powner != owner)
1568                 return -ENOENT;
1569         *powner = NULL;
1570         return rc;
1571 }
1572
1573 void usb_hub_release_all_ports(struct usb_device *hdev, void *owner)
1574 {
1575         int n;
1576         void **powner;
1577
1578         n = find_port_owner(hdev, 1, &powner);
1579         if (n == 0) {
1580                 for (; n < hdev->maxchild; (++n, ++powner)) {
1581                         if (*powner == owner)
1582                                 *powner = NULL;
1583                 }
1584         }
1585 }
1586
1587 /* The caller must hold udev's lock */
1588 bool usb_device_is_owned(struct usb_device *udev)
1589 {
1590         struct usb_hub *hub;
1591
1592         if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
1593                 return false;
1594         hub = hdev_to_hub(udev->parent);
1595         return !!hub->port_owners[udev->portnum - 1];
1596 }
1597
1598
1599 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1600 {
1601         int i;
1602
1603         for (i = 0; i < udev->maxchild; ++i) {
1604                 if (udev->children[i])
1605                         recursively_mark_NOTATTACHED(udev->children[i]);
1606         }
1607         if (udev->state == USB_STATE_SUSPENDED)
1608                 udev->active_duration -= jiffies;
1609         udev->state = USB_STATE_NOTATTACHED;
1610 }
1611
1612 /**
1613  * usb_set_device_state - change a device's current state (usbcore, hcds)
1614  * @udev: pointer to device whose state should be changed
1615  * @new_state: new state value to be stored
1616  *
1617  * udev->state is _not_ fully protected by the device lock.  Although
1618  * most transitions are made only while holding the lock, the state can
1619  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1620  * is so that devices can be marked as disconnected as soon as possible,
1621  * without having to wait for any semaphores to be released.  As a result,
1622  * all changes to any device's state must be protected by the
1623  * device_state_lock spinlock.
1624  *
1625  * Once a device has been added to the device tree, all changes to its state
1626  * should be made using this routine.  The state should _not_ be set directly.
1627  *
1628  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1629  * Otherwise udev->state is set to new_state, and if new_state is
1630  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1631  * to USB_STATE_NOTATTACHED.
1632  */
1633 void usb_set_device_state(struct usb_device *udev,
1634                 enum usb_device_state new_state)
1635 {
1636         unsigned long flags;
1637         int wakeup = -1;
1638
1639         spin_lock_irqsave(&device_state_lock, flags);
1640         if (udev->state == USB_STATE_NOTATTACHED)
1641                 ;       /* do nothing */
1642         else if (new_state != USB_STATE_NOTATTACHED) {
1643
1644                 /* root hub wakeup capabilities are managed out-of-band
1645                  * and may involve silicon errata ... ignore them here.
1646                  */
1647                 if (udev->parent) {
1648                         if (udev->state == USB_STATE_SUSPENDED
1649                                         || new_state == USB_STATE_SUSPENDED)
1650                                 ;       /* No change to wakeup settings */
1651                         else if (new_state == USB_STATE_CONFIGURED)
1652                                 wakeup = (udev->quirks &
1653                                         USB_QUIRK_IGNORE_REMOTE_WAKEUP) ? 0 :
1654                                         udev->actconfig->desc.bmAttributes &
1655                                         USB_CONFIG_ATT_WAKEUP;
1656                         else
1657                                 wakeup = 0;
1658                 }
1659                 if (udev->state == USB_STATE_SUSPENDED &&
1660                         new_state != USB_STATE_SUSPENDED)
1661                         udev->active_duration -= jiffies;
1662                 else if (new_state == USB_STATE_SUSPENDED &&
1663                                 udev->state != USB_STATE_SUSPENDED)
1664                         udev->active_duration += jiffies;
1665                 udev->state = new_state;
1666         } else
1667                 recursively_mark_NOTATTACHED(udev);
1668         spin_unlock_irqrestore(&device_state_lock, flags);
1669         if (wakeup >= 0)
1670                 device_set_wakeup_capable(&udev->dev, wakeup);
1671 }
1672 EXPORT_SYMBOL_GPL(usb_set_device_state);
1673
1674 /*
1675  * Choose a device number.
1676  *
1677  * Device numbers are used as filenames in usbfs.  On USB-1.1 and
1678  * USB-2.0 buses they are also used as device addresses, however on
1679  * USB-3.0 buses the address is assigned by the controller hardware
1680  * and it usually is not the same as the device number.
1681  *
1682  * WUSB devices are simple: they have no hubs behind, so the mapping
1683  * device <-> virtual port number becomes 1:1. Why? to simplify the
1684  * life of the device connection logic in
1685  * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
1686  * handshake we need to assign a temporary address in the unauthorized
1687  * space. For simplicity we use the first virtual port number found to
1688  * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
1689  * and that becomes it's address [X < 128] or its unauthorized address
1690  * [X | 0x80].
1691  *
1692  * We add 1 as an offset to the one-based USB-stack port number
1693  * (zero-based wusb virtual port index) for two reasons: (a) dev addr
1694  * 0 is reserved by USB for default address; (b) Linux's USB stack
1695  * uses always #1 for the root hub of the controller. So USB stack's
1696  * port #1, which is wusb virtual-port #0 has address #2.
1697  *
1698  * Devices connected under xHCI are not as simple.  The host controller
1699  * supports virtualization, so the hardware assigns device addresses and
1700  * the HCD must setup data structures before issuing a set address
1701  * command to the hardware.
1702  */
1703 static void choose_devnum(struct usb_device *udev)
1704 {
1705         int             devnum;
1706         struct usb_bus  *bus = udev->bus;
1707
1708         /* If khubd ever becomes multithreaded, this will need a lock */
1709         if (udev->wusb) {
1710                 devnum = udev->portnum + 1;
1711                 BUG_ON(test_bit(devnum, bus->devmap.devicemap));
1712         } else {
1713                 /* Try to allocate the next devnum beginning at
1714                  * bus->devnum_next. */
1715                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1716                                             bus->devnum_next);
1717                 if (devnum >= 128)
1718                         devnum = find_next_zero_bit(bus->devmap.devicemap,
1719                                                     128, 1);
1720                 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1721         }
1722         if (devnum < 128) {
1723                 set_bit(devnum, bus->devmap.devicemap);
1724                 udev->devnum = devnum;
1725         }
1726 }
1727
1728 static void release_devnum(struct usb_device *udev)
1729 {
1730         if (udev->devnum > 0) {
1731                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1732                 udev->devnum = -1;
1733         }
1734 }
1735
1736 static void update_devnum(struct usb_device *udev, int devnum)
1737 {
1738         /* The address for a WUSB device is managed by wusbcore. */
1739         if (!udev->wusb)
1740                 udev->devnum = devnum;
1741 }
1742
1743 static void hub_free_dev(struct usb_device *udev)
1744 {
1745         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1746
1747         /* Root hubs aren't real devices, so don't free HCD resources */
1748         if (hcd->driver->free_dev && udev->parent)
1749                 hcd->driver->free_dev(hcd, udev);
1750 }
1751
1752 /**
1753  * usb_disconnect - disconnect a device (usbcore-internal)
1754  * @pdev: pointer to device being disconnected
1755  * Context: !in_interrupt ()
1756  *
1757  * Something got disconnected. Get rid of it and all of its children.
1758  *
1759  * If *pdev is a normal device then the parent hub must already be locked.
1760  * If *pdev is a root hub then this routine will acquire the
1761  * usb_bus_list_lock on behalf of the caller.
1762  *
1763  * Only hub drivers (including virtual root hub drivers for host
1764  * controllers) should ever call this.
1765  *
1766  * This call is synchronous, and may not be used in an interrupt context.
1767  */
1768 void usb_disconnect(struct usb_device **pdev)
1769 {
1770         struct usb_device       *udev = *pdev;
1771         int                     i;
1772
1773         /* mark the device as inactive, so any further urb submissions for
1774          * this device (and any of its children) will fail immediately.
1775          * this quiesces everything except pending urbs.
1776          */
1777         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1778         dev_info(&udev->dev, "USB disconnect, device number %d\n",
1779                         udev->devnum);
1780
1781         usb_lock_device(udev);
1782
1783         /* Free up all the children before we remove this device */
1784         for (i = 0; i < USB_MAXCHILDREN; i++) {
1785                 if (udev->children[i])
1786                         usb_disconnect(&udev->children[i]);
1787         }
1788
1789         /* deallocate hcd/hardware state ... nuking all pending urbs and
1790          * cleaning up all state associated with the current configuration
1791          * so that the hardware is now fully quiesced.
1792          */
1793         dev_dbg (&udev->dev, "unregistering device\n");
1794         usb_disable_device(udev, 0);
1795         usb_hcd_synchronize_unlinks(udev);
1796
1797         usb_remove_ep_devs(&udev->ep0);
1798         usb_unlock_device(udev);
1799
1800         /* Unregister the device.  The device driver is responsible
1801          * for de-configuring the device and invoking the remove-device
1802          * notifier chain (used by usbfs and possibly others).
1803          */
1804         device_del(&udev->dev);
1805
1806         /* Free the device number and delete the parent's children[]
1807          * (or root_hub) pointer.
1808          */
1809         release_devnum(udev);
1810
1811         /* Avoid races with recursively_mark_NOTATTACHED() */
1812         spin_lock_irq(&device_state_lock);
1813         *pdev = NULL;
1814         spin_unlock_irq(&device_state_lock);
1815
1816         hub_free_dev(udev);
1817
1818         put_device(&udev->dev);
1819 }
1820
1821 #ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
1822 static void show_string(struct usb_device *udev, char *id, char *string)
1823 {
1824         if (!string)
1825                 return;
1826         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1827 }
1828
1829 static void announce_device(struct usb_device *udev)
1830 {
1831         dev_info(&udev->dev, "New USB device found, idVendor=%04x, idProduct=%04x\n",
1832                 le16_to_cpu(udev->descriptor.idVendor),
1833                 le16_to_cpu(udev->descriptor.idProduct));
1834         dev_info(&udev->dev,
1835                 "New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
1836                 udev->descriptor.iManufacturer,
1837                 udev->descriptor.iProduct,
1838                 udev->descriptor.iSerialNumber);
1839         show_string(udev, "Product", udev->product);
1840         show_string(udev, "Manufacturer", udev->manufacturer);
1841         show_string(udev, "SerialNumber", udev->serial);
1842 }
1843 #else
1844 static inline void announce_device(struct usb_device *udev) { }
1845 #endif
1846
1847 #ifdef  CONFIG_USB_OTG
1848 #include "otg_whitelist.h"
1849 #endif
1850
1851 /**
1852  * usb_enumerate_device_otg - FIXME (usbcore-internal)
1853  * @udev: newly addressed device (in ADDRESS state)
1854  *
1855  * Finish enumeration for On-The-Go devices
1856  */
1857 static int usb_enumerate_device_otg(struct usb_device *udev)
1858 {
1859         int err = 0;
1860
1861 #ifdef  CONFIG_USB_OTG
1862         /*
1863          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1864          * to wake us after we've powered off VBUS; and HNP, switching roles
1865          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1866          */
1867         if (!udev->bus->is_b_host
1868                         && udev->config
1869                         && udev->parent == udev->bus->root_hub) {
1870                 struct usb_otg_descriptor       *desc = NULL;
1871                 struct usb_bus                  *bus = udev->bus;
1872
1873                 /* descriptor may appear anywhere in config */
1874                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1875                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1876                                         USB_DT_OTG, (void **) &desc) == 0) {
1877                         if (desc->bmAttributes & USB_OTG_HNP) {
1878                                 unsigned                port1 = udev->portnum;
1879
1880                                 dev_info(&udev->dev,
1881                                         "Dual-Role OTG device on %sHNP port\n",
1882                                         (port1 == bus->otg_port)
1883                                                 ? "" : "non-");
1884
1885                                 /* enable HNP before suspend, it's simpler */
1886                                 if (port1 == bus->otg_port)
1887                                         bus->b_hnp_enable = 1;
1888                                 err = usb_control_msg(udev,
1889                                         usb_sndctrlpipe(udev, 0),
1890                                         USB_REQ_SET_FEATURE, 0,
1891                                         bus->b_hnp_enable
1892                                                 ? USB_DEVICE_B_HNP_ENABLE
1893                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1894                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1895                                 if (err < 0) {
1896                                         /* OTG MESSAGE: report errors here,
1897                                          * customize to match your product.
1898                                          */
1899                                         dev_info(&udev->dev,
1900                                                 "can't set HNP mode: %d\n",
1901                                                 err);
1902                                         bus->b_hnp_enable = 0;
1903                                 }
1904                         }
1905                 }
1906         }
1907
1908         if (!is_targeted(udev)) {
1909
1910                 /* Maybe it can talk to us, though we can't talk to it.
1911                  * (Includes HNP test device.)
1912                  */
1913                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1914                         err = usb_port_suspend(udev, PMSG_SUSPEND);
1915                         if (err < 0)
1916                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1917                 }
1918                 err = -ENOTSUPP;
1919                 goto fail;
1920         }
1921 fail:
1922 #endif
1923         return err;
1924 }
1925
1926
1927 /**
1928  * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
1929  * @udev: newly addressed device (in ADDRESS state)
1930  *
1931  * This is only called by usb_new_device() and usb_authorize_device()
1932  * and FIXME -- all comments that apply to them apply here wrt to
1933  * environment.
1934  *
1935  * If the device is WUSB and not authorized, we don't attempt to read
1936  * the string descriptors, as they will be errored out by the device
1937  * until it has been authorized.
1938  */
1939 static int usb_enumerate_device(struct usb_device *udev)
1940 {
1941         int err;
1942
1943         if (udev->config == NULL) {
1944                 err = usb_get_configuration(udev);
1945                 if (err < 0) {
1946                         dev_err(&udev->dev, "can't read configurations, error %d\n",
1947                                 err);
1948                         return err;
1949                 }
1950         }
1951         if (udev->wusb == 1 && udev->authorized == 0) {
1952                 udev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1953                 udev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1954                 udev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1955         }
1956         else {
1957                 /* read the standard strings and cache them if present */
1958                 udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1959                 udev->manufacturer = usb_cache_string(udev,
1960                                                       udev->descriptor.iManufacturer);
1961                 udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1962         }
1963         err = usb_enumerate_device_otg(udev);
1964         if (err < 0)
1965                 return err;
1966
1967         usb_detect_interface_quirks(udev);
1968
1969         return 0;
1970 }
1971
1972
1973 /**
1974  * usb_new_device - perform initial device setup (usbcore-internal)
1975  * @udev: newly addressed device (in ADDRESS state)
1976  *
1977  * This is called with devices which have been detected but not fully
1978  * enumerated.  The device descriptor is available, but not descriptors
1979  * for any device configuration.  The caller must have locked either
1980  * the parent hub (if udev is a normal device) or else the
1981  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1982  * udev has already been installed, but udev is not yet visible through
1983  * sysfs or other filesystem code.
1984  *
1985  * It will return if the device is configured properly or not.  Zero if
1986  * the interface was registered with the driver core; else a negative
1987  * errno value.
1988  *
1989  * This call is synchronous, and may not be used in an interrupt context.
1990  *
1991  * Only the hub driver or root-hub registrar should ever call this.
1992  */
1993 int usb_new_device(struct usb_device *udev)
1994 {
1995         int err;
1996
1997         if (udev->parent) {
1998                 /* Initialize non-root-hub device wakeup to disabled;
1999                  * device (un)configuration controls wakeup capable
2000                  * sysfs power/wakeup controls wakeup enabled/disabled
2001                  */
2002                 device_init_wakeup(&udev->dev, 0);
2003         }
2004
2005         /* Tell the runtime-PM framework the device is active */
2006         pm_runtime_set_active(&udev->dev);
2007         pm_runtime_get_noresume(&udev->dev);
2008         pm_runtime_use_autosuspend(&udev->dev);
2009         pm_runtime_enable(&udev->dev);
2010
2011         /* By default, forbid autosuspend for all devices.  It will be
2012          * allowed for hubs during binding.
2013          */
2014         usb_disable_autosuspend(udev);
2015
2016         err = usb_enumerate_device(udev);       /* Read descriptors */
2017         if (err < 0)
2018                 goto fail;
2019         dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
2020                         udev->devnum, udev->bus->busnum,
2021                         (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2022         /* export the usbdev device-node for libusb */
2023         udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
2024                         (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2025
2026         /* Tell the world! */
2027         announce_device(udev);
2028
2029         if (udev->serial)
2030                 add_device_randomness(udev->serial, strlen(udev->serial));
2031         if (udev->product)
2032                 add_device_randomness(udev->product, strlen(udev->product));
2033         if (udev->manufacturer)
2034                 add_device_randomness(udev->manufacturer,
2035                                       strlen(udev->manufacturer));
2036
2037         device_enable_async_suspend(&udev->dev);
2038         /* Register the device.  The device driver is responsible
2039          * for configuring the device and invoking the add-device
2040          * notifier chain (used by usbfs and possibly others).
2041          */
2042         err = device_add(&udev->dev);
2043         if (err) {
2044                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
2045                 goto fail;
2046         }
2047
2048         (void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
2049         usb_mark_last_busy(udev);
2050         pm_runtime_put_sync_autosuspend(&udev->dev);
2051         return err;
2052
2053 fail:
2054         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2055         pm_runtime_disable(&udev->dev);
2056         pm_runtime_set_suspended(&udev->dev);
2057         return err;
2058 }
2059
2060
2061 /**
2062  * usb_deauthorize_device - deauthorize a device (usbcore-internal)
2063  * @usb_dev: USB device
2064  *
2065  * Move the USB device to a very basic state where interfaces are disabled
2066  * and the device is in fact unconfigured and unusable.
2067  *
2068  * We share a lock (that we have) with device_del(), so we need to
2069  * defer its call.
2070  */
2071 int usb_deauthorize_device(struct usb_device *usb_dev)
2072 {
2073         usb_lock_device(usb_dev);
2074         if (usb_dev->authorized == 0)
2075                 goto out_unauthorized;
2076
2077         usb_dev->authorized = 0;
2078         usb_set_configuration(usb_dev, -1);
2079
2080         kfree(usb_dev->product);
2081         usb_dev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
2082         kfree(usb_dev->manufacturer);
2083         usb_dev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
2084         kfree(usb_dev->serial);
2085         usb_dev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
2086
2087         usb_destroy_configuration(usb_dev);
2088         usb_dev->descriptor.bNumConfigurations = 0;
2089
2090 out_unauthorized:
2091         usb_unlock_device(usb_dev);
2092         return 0;
2093 }
2094
2095
2096 int usb_authorize_device(struct usb_device *usb_dev)
2097 {
2098         int result = 0, c;
2099
2100         usb_lock_device(usb_dev);
2101         if (usb_dev->authorized == 1)
2102                 goto out_authorized;
2103
2104         result = usb_autoresume_device(usb_dev);
2105         if (result < 0) {
2106                 dev_err(&usb_dev->dev,
2107                         "can't autoresume for authorization: %d\n", result);
2108                 goto error_autoresume;
2109         }
2110         result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
2111         if (result < 0) {
2112                 dev_err(&usb_dev->dev, "can't re-read device descriptor for "
2113                         "authorization: %d\n", result);
2114                 goto error_device_descriptor;
2115         }
2116
2117         kfree(usb_dev->product);
2118         usb_dev->product = NULL;
2119         kfree(usb_dev->manufacturer);
2120         usb_dev->manufacturer = NULL;
2121         kfree(usb_dev->serial);
2122         usb_dev->serial = NULL;
2123
2124         usb_dev->authorized = 1;
2125         result = usb_enumerate_device(usb_dev);
2126         if (result < 0)
2127                 goto error_enumerate;
2128         /* Choose and set the configuration.  This registers the interfaces
2129          * with the driver core and lets interface drivers bind to them.
2130          */
2131         c = usb_choose_configuration(usb_dev);
2132         if (c >= 0) {
2133                 result = usb_set_configuration(usb_dev, c);
2134                 if (result) {
2135                         dev_err(&usb_dev->dev,
2136                                 "can't set config #%d, error %d\n", c, result);
2137                         /* This need not be fatal.  The user can try to
2138                          * set other configurations. */
2139                 }
2140         }
2141         dev_info(&usb_dev->dev, "authorized to connect\n");
2142
2143 error_enumerate:
2144 error_device_descriptor:
2145         usb_autosuspend_device(usb_dev);
2146 error_autoresume:
2147 out_authorized:
2148         usb_unlock_device(usb_dev);     // complements locktree
2149         return result;
2150 }
2151
2152
2153 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
2154 static unsigned hub_is_wusb(struct usb_hub *hub)
2155 {
2156         struct usb_hcd *hcd;
2157         if (hub->hdev->parent != NULL)  /* not a root hub? */
2158                 return 0;
2159         hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
2160         return hcd->wireless;
2161 }
2162
2163
2164 #define PORT_RESET_TRIES        5
2165 #define SET_ADDRESS_TRIES       2
2166 #define GET_DESCRIPTOR_TRIES    2
2167 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
2168 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
2169
2170 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
2171 #define HUB_SHORT_RESET_TIME    10
2172 #define HUB_BH_RESET_TIME       50
2173 #define HUB_LONG_RESET_TIME     200
2174 #define HUB_RESET_TIMEOUT       800
2175
2176 /* Is a USB 3.0 port in the Inactive or Complinance Mode state?
2177  * Port worm reset is required to recover
2178  */
2179 static bool hub_port_warm_reset_required(struct usb_hub *hub, u16 portstatus)
2180 {
2181         return hub_is_superspeed(hub->hdev) &&
2182                 (((portstatus & USB_PORT_STAT_LINK_STATE) ==
2183                   USB_SS_PORT_LS_SS_INACTIVE) ||
2184                  ((portstatus & USB_PORT_STAT_LINK_STATE) ==
2185                   USB_SS_PORT_LS_COMP_MOD)) ;
2186 }
2187
2188 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
2189                         struct usb_device *udev, unsigned int delay, bool warm)
2190 {
2191         int delay_time, ret;
2192         u16 portstatus;
2193         u16 portchange;
2194
2195         for (delay_time = 0;
2196                         delay_time < HUB_RESET_TIMEOUT;
2197                         delay_time += delay) {
2198                 /* wait to give the device a chance to reset */
2199                 msleep(delay);
2200
2201                 /* read and decode port status */
2202                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2203                 if (ret < 0)
2204                         return ret;
2205
2206                 /* The port state is unknown until the reset completes. */
2207                 if ((portstatus & USB_PORT_STAT_RESET))
2208                         goto delay;
2209
2210                 if (hub_port_warm_reset_required(hub, portstatus))
2211                         return -ENOTCONN;
2212
2213                 /* Device went away? */
2214                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
2215                         return -ENOTCONN;
2216
2217                 /* bomb out completely if the connection bounced.  A USB 3.0
2218                  * connection may bounce if multiple warm resets were issued,
2219                  * but the device may have successfully re-connected. Ignore it.
2220                  */
2221                 if (!hub_is_superspeed(hub->hdev) &&
2222                                 (portchange & USB_PORT_STAT_C_CONNECTION))
2223                         return -ENOTCONN;
2224
2225                 if ((portstatus & USB_PORT_STAT_ENABLE)) {
2226                         if (!udev)
2227                                 return 0;
2228
2229                         if (hub_is_wusb(hub))
2230                                 udev->speed = USB_SPEED_WIRELESS;
2231                         else if (hub_is_superspeed(hub->hdev))
2232                                 udev->speed = USB_SPEED_SUPER;
2233                         else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
2234                                 udev->speed = USB_SPEED_HIGH;
2235                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
2236                                 udev->speed = USB_SPEED_LOW;
2237                         else
2238                                 udev->speed = USB_SPEED_FULL;
2239                         return 0;
2240                 }
2241
2242 delay:
2243                 /* switch to the long delay after two short delay failures */
2244                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
2245                         delay = HUB_LONG_RESET_TIME;
2246
2247                 dev_dbg (hub->intfdev,
2248                         "port %d not %sreset yet, waiting %dms\n",
2249                         port1, warm ? "warm " : "", delay);
2250         }
2251
2252         return -EBUSY;
2253 }
2254
2255 /* Handle port reset and port warm(BH) reset (for USB3 protocol ports) */
2256 static int hub_port_reset(struct usb_hub *hub, int port1,
2257                         struct usb_device *udev, unsigned int delay, bool warm)
2258 {
2259         int i, status;
2260         u16 portchange, portstatus;
2261
2262         if (!hub_is_superspeed(hub->hdev)) {
2263                 if (warm) {
2264                         dev_err(hub->intfdev, "only USB3 hub support "
2265                                                 "warm reset\n");
2266                         return -EINVAL;
2267                 }
2268                 /* Block EHCI CF initialization during the port reset.
2269                  * Some companion controllers don't like it when they mix.
2270                  */
2271                 down_read(&ehci_cf_port_reset_rwsem);
2272         } else if (!warm) {
2273                 /*
2274                  * If the caller hasn't explicitly requested a warm reset,
2275                  * double check and see if one is needed.
2276                  */
2277                 if (hub_port_status(hub, port1, &portstatus, &portchange) == 0)
2278                         if (hub_port_warm_reset_required(hub, portstatus))
2279                                 warm = true;
2280         }
2281
2282         /* Reset the port */
2283         for (i = 0; i < PORT_RESET_TRIES; i++) {
2284                 status = set_port_feature(hub->hdev, port1, (warm ?
2285                                         USB_PORT_FEAT_BH_PORT_RESET :
2286                                         USB_PORT_FEAT_RESET));
2287                 if (status) {
2288                         dev_err(hub->intfdev,
2289                                         "cannot %sreset port %d (err = %d)\n",
2290                                         warm ? "warm " : "", port1, status);
2291                 } else {
2292                         status = hub_port_wait_reset(hub, port1, udev, delay,
2293                                                                 warm);
2294                         if (status && status != -ENOTCONN)
2295                                 dev_dbg(hub->intfdev,
2296                                                 "port_wait_reset: err = %d\n",
2297                                                 status);
2298                 }
2299
2300                 /* Check for disconnect or reset */
2301                 if (status == 0 || status == -ENOTCONN || status == -ENODEV) {
2302                         clear_port_feature(hub->hdev, port1,
2303                                         USB_PORT_FEAT_C_RESET);
2304
2305                         if (!hub_is_superspeed(hub->hdev))
2306                                 goto done;
2307
2308                         clear_port_feature(hub->hdev, port1,
2309                                         USB_PORT_FEAT_C_BH_PORT_RESET);
2310                         clear_port_feature(hub->hdev, port1,
2311                                         USB_PORT_FEAT_C_PORT_LINK_STATE);
2312                         clear_port_feature(hub->hdev, port1,
2313                                         USB_PORT_FEAT_C_CONNECTION);
2314
2315                         /*
2316                          * If a USB 3.0 device migrates from reset to an error
2317                          * state, re-issue the warm reset.
2318                          */
2319                         if (hub_port_status(hub, port1,
2320                                         &portstatus, &portchange) < 0)
2321                                 goto done;
2322
2323                         if (!hub_port_warm_reset_required(hub, portstatus))
2324                                 goto done;
2325
2326                         /*
2327                          * If the port is in SS.Inactive or Compliance Mode, the
2328                          * hot or warm reset failed.  Try another warm reset.
2329                          */
2330                         if (!warm) {
2331                                 dev_dbg(hub->intfdev, "hot reset failed, warm reset port %d\n",
2332                                                 port1);
2333                                 warm = true;
2334                         }
2335                 }
2336
2337                 dev_dbg (hub->intfdev,
2338                         "port %d not enabled, trying %sreset again...\n",
2339                         port1, warm ? "warm " : "");
2340                 delay = HUB_LONG_RESET_TIME;
2341         }
2342
2343         dev_err (hub->intfdev,
2344                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
2345                 port1);
2346
2347 done:
2348         if (status == 0) {
2349                 /* TRSTRCY = 10 ms; plus some extra */
2350                 msleep(10 + 40);
2351                 if (udev) {
2352                         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2353
2354                         update_devnum(udev, 0);
2355                         /* The xHC may think the device is already reset,
2356                          * so ignore the status.
2357                          */
2358                         if (hcd->driver->reset_device)
2359                                 hcd->driver->reset_device(hcd, udev);
2360
2361                         usb_set_device_state(udev, USB_STATE_DEFAULT);
2362                 }
2363         } else {
2364                 if (udev)
2365                         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2366         }
2367
2368         if (!hub_is_superspeed(hub->hdev))
2369                 up_read(&ehci_cf_port_reset_rwsem);
2370
2371         return status;
2372 }
2373
2374 /* Check if a port is power on */
2375 static int port_is_power_on(struct usb_hub *hub, unsigned portstatus)
2376 {
2377         int ret = 0;
2378
2379         if (hub_is_superspeed(hub->hdev)) {
2380                 if (portstatus & USB_SS_PORT_STAT_POWER)
2381                         ret = 1;
2382         } else {
2383                 if (portstatus & USB_PORT_STAT_POWER)
2384                         ret = 1;
2385         }
2386
2387         return ret;
2388 }
2389
2390 #ifdef  CONFIG_PM
2391
2392 /* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */
2393 static int port_is_suspended(struct usb_hub *hub, unsigned portstatus)
2394 {
2395         int ret = 0;
2396
2397         if (hub_is_superspeed(hub->hdev)) {
2398                 if ((portstatus & USB_PORT_STAT_LINK_STATE)
2399                                 == USB_SS_PORT_LS_U3)
2400                         ret = 1;
2401         } else {
2402                 if (portstatus & USB_PORT_STAT_SUSPEND)
2403                         ret = 1;
2404         }
2405
2406         return ret;
2407 }
2408
2409 /* Determine whether the device on a port is ready for a normal resume,
2410  * is ready for a reset-resume, or should be disconnected.
2411  */
2412 static int check_port_resume_type(struct usb_device *udev,
2413                 struct usb_hub *hub, int port1,
2414                 int status, unsigned portchange, unsigned portstatus)
2415 {
2416         /* Is the device still present? */
2417         if (status || port_is_suspended(hub, portstatus) ||
2418                         !port_is_power_on(hub, portstatus) ||
2419                         !(portstatus & USB_PORT_STAT_CONNECTION)) {
2420                 if (status >= 0)
2421                         status = -ENODEV;
2422         }
2423
2424         /* Can't do a normal resume if the port isn't enabled,
2425          * so try a reset-resume instead.
2426          */
2427         else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
2428                 if (udev->persist_enabled)
2429                         udev->reset_resume = 1;
2430                 else
2431                         status = -ENODEV;
2432         }
2433
2434         if (status) {
2435                 dev_dbg(hub->intfdev,
2436                                 "port %d status %04x.%04x after resume, %d\n",
2437                                 port1, portchange, portstatus, status);
2438         } else if (udev->reset_resume) {
2439
2440                 /* Late port handoff can set status-change bits */
2441                 if (portchange & USB_PORT_STAT_C_CONNECTION)
2442                         clear_port_feature(hub->hdev, port1,
2443                                         USB_PORT_FEAT_C_CONNECTION);
2444                 if (portchange & USB_PORT_STAT_C_ENABLE)
2445                         clear_port_feature(hub->hdev, port1,
2446                                         USB_PORT_FEAT_C_ENABLE);
2447         }
2448
2449         return status;
2450 }
2451
2452 #ifdef  CONFIG_USB_SUSPEND
2453
2454 /*
2455  * usb_port_suspend - suspend a usb device's upstream port
2456  * @udev: device that's no longer in active use, not a root hub
2457  * Context: must be able to sleep; device not locked; pm locks held
2458  *
2459  * Suspends a USB device that isn't in active use, conserving power.
2460  * Devices may wake out of a suspend, if anything important happens,
2461  * using the remote wakeup mechanism.  They may also be taken out of
2462  * suspend by the host, using usb_port_resume().  It's also routine
2463  * to disconnect devices while they are suspended.
2464  *
2465  * This only affects the USB hardware for a device; its interfaces
2466  * (and, for hubs, child devices) must already have been suspended.
2467  *
2468  * Selective port suspend reduces power; most suspended devices draw
2469  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
2470  * All devices below the suspended port are also suspended.
2471  *
2472  * Devices leave suspend state when the host wakes them up.  Some devices
2473  * also support "remote wakeup", where the device can activate the USB
2474  * tree above them to deliver data, such as a keypress or packet.  In
2475  * some cases, this wakes the USB host.
2476  *
2477  * Suspending OTG devices may trigger HNP, if that's been enabled
2478  * between a pair of dual-role devices.  That will change roles, such
2479  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
2480  *
2481  * Devices on USB hub ports have only one "suspend" state, corresponding
2482  * to ACPI D2, "may cause the device to lose some context".
2483  * State transitions include:
2484  *
2485  *   - suspend, resume ... when the VBUS power link stays live
2486  *   - suspend, disconnect ... VBUS lost
2487  *
2488  * Once VBUS drop breaks the circuit, the port it's using has to go through
2489  * normal re-enumeration procedures, starting with enabling VBUS power.
2490  * Other than re-initializing the hub (plug/unplug, except for root hubs),
2491  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
2492  * timer, no SRP, no requests through sysfs.
2493  *
2494  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
2495  * the root hub for their bus goes into global suspend ... so we don't
2496  * (falsely) update the device power state to say it suspended.
2497  *
2498  * Returns 0 on success, else negative errno.
2499  */
2500 int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2501 {
2502         struct usb_hub  *hub = hdev_to_hub(udev->parent);
2503         int             port1 = udev->portnum;
2504         int             status;
2505
2506         /* enable remote wakeup when appropriate; this lets the device
2507          * wake up the upstream hub (including maybe the root hub).
2508          *
2509          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
2510          * we don't explicitly enable it here.
2511          */
2512         if (udev->do_remote_wakeup) {
2513                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2514                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
2515                                 USB_DEVICE_REMOTE_WAKEUP, 0,
2516                                 NULL, 0,
2517                                 USB_CTRL_SET_TIMEOUT);
2518                 if (status) {
2519                         dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
2520                                         status);
2521                         /* bail if autosuspend is requested */
2522                         if (PMSG_IS_AUTO(msg))
2523                                 return status;
2524                 }
2525         }
2526
2527         /* disable USB2 hardware LPM */
2528         if (udev->usb2_hw_lpm_enabled == 1)
2529                 usb_set_usb2_hardware_lpm(udev, 0);
2530
2531         /* see 7.1.7.6 */
2532         if (hub_is_superspeed(hub->hdev))
2533                 status = set_port_feature(hub->hdev,
2534                                 port1 | (USB_SS_PORT_LS_U3 << 3),
2535                                 USB_PORT_FEAT_LINK_STATE);
2536         else
2537                 status = set_port_feature(hub->hdev, port1,
2538                                                 USB_PORT_FEAT_SUSPEND);
2539         if (status) {
2540                 dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",
2541                                 port1, status);
2542                 /* paranoia:  "should not happen" */
2543                 if (udev->do_remote_wakeup)
2544                         (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2545                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
2546                                 USB_DEVICE_REMOTE_WAKEUP, 0,
2547                                 NULL, 0,
2548                                 USB_CTRL_SET_TIMEOUT);
2549
2550                 /* Try to enable USB2 hardware LPM again */
2551                 if (udev->usb2_hw_lpm_capable == 1)
2552                         usb_set_usb2_hardware_lpm(udev, 1);
2553
2554                 /* System sleep transitions should never fail */
2555                 if (!PMSG_IS_AUTO(msg))
2556                         status = 0;
2557         } else {
2558                 /* device has up to 10 msec to fully suspend */
2559                 dev_dbg(&udev->dev, "usb %ssuspend, wakeup %d\n",
2560                                 (PMSG_IS_AUTO(msg) ? "auto-" : ""),
2561                                 udev->do_remote_wakeup);
2562                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
2563                 msleep(10);
2564         }
2565         usb_mark_last_busy(hub->hdev);
2566         return status;
2567 }
2568
2569 /*
2570  * If the USB "suspend" state is in use (rather than "global suspend"),
2571  * many devices will be individually taken out of suspend state using
2572  * special "resume" signaling.  This routine kicks in shortly after
2573  * hardware resume signaling is finished, either because of selective
2574  * resume (by host) or remote wakeup (by device) ... now see what changed
2575  * in the tree that's rooted at this device.
2576  *
2577  * If @udev->reset_resume is set then the device is reset before the
2578  * status check is done.
2579  */
2580 static int finish_port_resume(struct usb_device *udev)
2581 {
2582         int     status = 0;
2583         u16     devstatus = 0;
2584
2585         /* caller owns the udev device lock */
2586         dev_dbg(&udev->dev, "%s\n",
2587                 udev->reset_resume ? "finish reset-resume" : "finish resume");
2588
2589         /* usb ch9 identifies four variants of SUSPENDED, based on what
2590          * state the device resumes to.  Linux currently won't see the
2591          * first two on the host side; they'd be inside hub_port_init()
2592          * during many timeouts, but khubd can't suspend until later.
2593          */
2594         usb_set_device_state(udev, udev->actconfig
2595                         ? USB_STATE_CONFIGURED
2596                         : USB_STATE_ADDRESS);
2597
2598         /* 10.5.4.5 says not to reset a suspended port if the attached
2599          * device is enabled for remote wakeup.  Hence the reset
2600          * operation is carried out here, after the port has been
2601          * resumed.
2602          */
2603         if (udev->reset_resume)
2604  retry_reset_resume:
2605                 status = usb_reset_and_verify_device(udev);
2606
2607         /* 10.5.4.5 says be sure devices in the tree are still there.
2608          * For now let's assume the device didn't go crazy on resume,
2609          * and device drivers will know about any resume quirks.
2610          */
2611         if (status == 0) {
2612                 devstatus = 0;
2613                 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
2614                 if (status >= 0)
2615                         status = (status > 0 ? 0 : -ENODEV);
2616
2617                 /* If a normal resume failed, try doing a reset-resume */
2618                 if (status && !udev->reset_resume && udev->persist_enabled) {
2619                         dev_dbg(&udev->dev, "retry with reset-resume\n");
2620                         udev->reset_resume = 1;
2621                         goto retry_reset_resume;
2622                 }
2623         }
2624
2625         if (status) {
2626                 dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
2627                                 status);
2628         /*
2629          * There are a few quirky devices which violate the standard
2630          * by claiming to have remote wakeup enabled after a reset,
2631          * which crash if the feature is cleared, hence check for
2632          * udev->reset_resume
2633          */
2634         } else if (udev->actconfig && !udev->reset_resume) {
2635                 le16_to_cpus(&devstatus);
2636                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
2637                         status = usb_control_msg(udev,
2638                                         usb_sndctrlpipe(udev, 0),
2639                                         USB_REQ_CLEAR_FEATURE,
2640                                                 USB_RECIP_DEVICE,
2641                                         USB_DEVICE_REMOTE_WAKEUP, 0,
2642                                         NULL, 0,
2643                                         USB_CTRL_SET_TIMEOUT);
2644                         if (status)
2645                                 dev_dbg(&udev->dev,
2646                                         "disable remote wakeup, status %d\n",
2647                                         status);
2648                 }
2649                 status = 0;
2650         }
2651         return status;
2652 }
2653
2654 /*
2655  * There are some SS USB devices which take longer time for link training.
2656  * XHCI specs 4.19.4 says that when Link training is successful, port
2657  * sets CSC bit to 1. So if SW reads port status before successful link
2658  * training, then it will not find device to be present.
2659  * USB Analyzer log with such buggy devices show that in some cases
2660  * device switch on the RX termination after long delay of host enabling
2661  * the VBUS. In few other cases it has been seen that device fails to
2662  * negotiate link training in first attempt. It has been
2663  * reported till now that few devices take as long as 2000 ms to train
2664  * the link after host enabling its VBUS and termination. Following
2665  * routine implements a 2000 ms timeout for link training. If in a case
2666  * link trains before timeout, loop will exit earlier.
2667  *
2668  * FIXME: If a device was connected before suspend, but was removed
2669  * while system was asleep, then the loop in the following routine will
2670  * only exit at timeout.
2671  *
2672  * This routine should only be called when persist is enabled for a SS
2673  * device.
2674  */
2675 static int wait_for_ss_port_enable(struct usb_device *udev,
2676                 struct usb_hub *hub, int *port1,
2677                 u16 *portchange, u16 *portstatus)
2678 {
2679         int status = 0, delay_ms = 0;
2680
2681         while (delay_ms < 2000) {
2682                 if (status || *portstatus & USB_PORT_STAT_CONNECTION)
2683                         break;
2684                 msleep(20);
2685                 delay_ms += 20;
2686                 status = hub_port_status(hub, *port1, portstatus, portchange);
2687         }
2688         return status;
2689 }
2690
2691 /*
2692  * usb_port_resume - re-activate a suspended usb device's upstream port
2693  * @udev: device to re-activate, not a root hub
2694  * Context: must be able to sleep; device not locked; pm locks held
2695  *
2696  * This will re-activate the suspended device, increasing power usage
2697  * while letting drivers communicate again with its endpoints.
2698  * USB resume explicitly guarantees that the power session between
2699  * the host and the device is the same as it was when the device
2700  * suspended.
2701  *
2702  * If @udev->reset_resume is set then this routine won't check that the
2703  * port is still enabled.  Furthermore, finish_port_resume() above will
2704  * reset @udev.  The end result is that a broken power session can be
2705  * recovered and @udev will appear to persist across a loss of VBUS power.
2706  *
2707  * For example, if a host controller doesn't maintain VBUS suspend current
2708  * during a system sleep or is reset when the system wakes up, all the USB
2709  * power sessions below it will be broken.  This is especially troublesome
2710  * for mass-storage devices containing mounted filesystems, since the
2711  * device will appear to have disconnected and all the memory mappings
2712  * to it will be lost.  Using the USB_PERSIST facility, the device can be
2713  * made to appear as if it had not disconnected.
2714  *
2715  * This facility can be dangerous.  Although usb_reset_and_verify_device() makes
2716  * every effort to insure that the same device is present after the
2717  * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
2718  * quite possible for a device to remain unaltered but its media to be
2719  * changed.  If the user replaces a flash memory card while the system is
2720  * asleep, he will have only himself to blame when the filesystem on the
2721  * new card is corrupted and the system crashes.
2722  *
2723  * Returns 0 on success, else negative errno.
2724  */
2725 int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2726 {
2727         struct usb_hub  *hub = hdev_to_hub(udev->parent);
2728         int             port1 = udev->portnum;
2729         int             status;
2730         u16             portchange, portstatus;
2731
2732         /* Skip the initial Clear-Suspend step for a remote wakeup */
2733         status = hub_port_status(hub, port1, &portstatus, &portchange);
2734         if (status == 0 && !port_is_suspended(hub, portstatus))
2735                 goto SuspendCleared;
2736
2737         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
2738
2739         set_bit(port1, hub->busy_bits);
2740
2741         /* see 7.1.7.7; affects power usage, but not budgeting */
2742         if (hub_is_superspeed(hub->hdev))
2743                 status = set_port_feature(hub->hdev,
2744                                 port1 | (USB_SS_PORT_LS_U0 << 3),
2745                                 USB_PORT_FEAT_LINK_STATE);
2746         else
2747                 status = clear_port_feature(hub->hdev,
2748                                 port1, USB_PORT_FEAT_SUSPEND);
2749         if (status) {
2750                 dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
2751                                 port1, status);
2752         } else {
2753                 /* drive resume for at least 20 msec */
2754                 dev_dbg(&udev->dev, "usb %sresume\n",
2755                                 (PMSG_IS_AUTO(msg) ? "auto-" : ""));
2756                 msleep(25);
2757
2758                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
2759                  * stop resume signaling.  Then finish the resume
2760                  * sequence.
2761                  */
2762                 status = hub_port_status(hub, port1, &portstatus, &portchange);
2763
2764                 /* TRSMRCY = 10 msec */
2765                 msleep(10);
2766         }
2767
2768  SuspendCleared:
2769         if (status == 0) {
2770                 if (hub_is_superspeed(hub->hdev)) {
2771                         if (portchange & USB_PORT_STAT_C_LINK_STATE)
2772                                 clear_port_feature(hub->hdev, port1,
2773                                         USB_PORT_FEAT_C_PORT_LINK_STATE);
2774                 } else {
2775                         if (portchange & USB_PORT_STAT_C_SUSPEND)
2776                                 clear_port_feature(hub->hdev, port1,
2777                                                 USB_PORT_FEAT_C_SUSPEND);
2778                 }
2779         }
2780
2781         clear_bit(port1, hub->busy_bits);
2782
2783         if (udev->persist_enabled && hub_is_superspeed(hub->hdev))
2784                 status = wait_for_ss_port_enable(udev, hub, &port1, &portchange,
2785                                 &portstatus);
2786
2787         status = check_port_resume_type(udev,
2788                         hub, port1, status, portchange, portstatus);
2789         if (status == 0)
2790                 status = finish_port_resume(udev);
2791         if (status < 0) {
2792                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2793                 hub_port_logical_disconnect(hub, port1);
2794         } else  {
2795                 /* Try to enable USB2 hardware LPM */
2796                 if (udev->usb2_hw_lpm_capable == 1)
2797                         usb_set_usb2_hardware_lpm(udev, 1);
2798         }
2799
2800         return status;
2801 }
2802
2803 /* caller has locked udev */
2804 int usb_remote_wakeup(struct usb_device *udev)
2805 {
2806         int     status = 0;
2807
2808         if (udev->state == USB_STATE_SUSPENDED) {
2809                 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
2810                 status = usb_autoresume_device(udev);
2811                 if (status == 0) {
2812                         /* Let the drivers do their thing, then... */
2813                         usb_autosuspend_device(udev);
2814                 }
2815         }
2816         return status;
2817 }
2818
2819 #else   /* CONFIG_USB_SUSPEND */
2820
2821 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
2822
2823 int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2824 {
2825         return 0;
2826 }
2827
2828 /* However we may need to do a reset-resume */
2829
2830 int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2831 {
2832         struct usb_hub  *hub = hdev_to_hub(udev->parent);
2833         int             port1 = udev->portnum;
2834         int             status;
2835         u16             portchange, portstatus;
2836
2837         status = hub_port_status(hub, port1, &portstatus, &portchange);
2838         status = check_port_resume_type(udev,
2839                         hub, port1, status, portchange, portstatus);
2840
2841         if (status) {
2842                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2843                 hub_port_logical_disconnect(hub, port1);
2844         } else if (udev->reset_resume) {
2845                 dev_dbg(&udev->dev, "reset-resume\n");
2846                 status = usb_reset_and_verify_device(udev);
2847         }
2848         return status;
2849 }
2850
2851 #endif
2852
2853 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
2854 {
2855         struct usb_hub          *hub = usb_get_intfdata (intf);
2856         struct usb_device       *hdev = hub->hdev;
2857         unsigned                port1;
2858
2859         /* Warn if children aren't already suspended */
2860         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
2861                 struct usb_device       *udev;
2862
2863                 udev = hdev->children [port1-1];
2864                 if (udev && udev->can_submit) {
2865                         dev_warn(&intf->dev, "port %d nyet suspended\n", port1);
2866                         if (PMSG_IS_AUTO(msg))
2867                                 return -EBUSY;
2868                 }
2869         }
2870
2871         dev_dbg(&intf->dev, "%s\n", __func__);
2872
2873         /* stop khubd and related activity */
2874         hub_quiesce(hub, HUB_SUSPEND);
2875         return 0;
2876 }
2877
2878 static int hub_resume(struct usb_interface *intf)
2879 {
2880         struct usb_hub *hub = usb_get_intfdata(intf);
2881
2882         dev_dbg(&intf->dev, "%s\n", __func__);
2883         hub_activate(hub, HUB_RESUME);
2884         return 0;
2885 }
2886
2887 static int hub_reset_resume(struct usb_interface *intf)
2888 {
2889         struct usb_hub *hub = usb_get_intfdata(intf);
2890
2891         dev_dbg(&intf->dev, "%s\n", __func__);
2892         hub_activate(hub, HUB_RESET_RESUME);
2893         return 0;
2894 }
2895
2896 /**
2897  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
2898  * @rhdev: struct usb_device for the root hub
2899  *
2900  * The USB host controller driver calls this function when its root hub
2901  * is resumed and Vbus power has been interrupted or the controller
2902  * has been reset.  The routine marks @rhdev as having lost power.
2903  * When the hub driver is resumed it will take notice and carry out
2904  * power-session recovery for all the "USB-PERSIST"-enabled child devices;
2905  * the others will be disconnected.
2906  */
2907 void usb_root_hub_lost_power(struct usb_device *rhdev)
2908 {
2909         dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
2910         rhdev->reset_resume = 1;
2911 }
2912 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
2913
2914 #else   /* CONFIG_PM */
2915
2916 #define hub_suspend             NULL
2917 #define hub_resume              NULL
2918 #define hub_reset_resume        NULL
2919 #endif
2920
2921
2922 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2923  *
2924  * Between connect detection and reset signaling there must be a delay
2925  * of 100ms at least for debounce and power-settling.  The corresponding
2926  * timer shall restart whenever the downstream port detects a disconnect.
2927  * 
2928  * Apparently there are some bluetooth and irda-dongles and a number of
2929  * low-speed devices for which this debounce period may last over a second.
2930  * Not covered by the spec - but easy to deal with.
2931  *
2932  * This implementation uses a 1500ms total debounce timeout; if the
2933  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2934  * every 25ms for transient disconnects.  When the port status has been
2935  * unchanged for 100ms it returns the port status.
2936  */
2937 static int hub_port_debounce(struct usb_hub *hub, int port1)
2938 {
2939         int ret;
2940         int total_time, stable_time = 0;
2941         u16 portchange, portstatus;
2942         unsigned connection = 0xffff;
2943
2944         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2945                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2946                 if (ret < 0)
2947                         return ret;
2948
2949                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2950                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2951                         stable_time += HUB_DEBOUNCE_STEP;
2952                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2953                                 break;
2954                 } else {
2955                         stable_time = 0;
2956                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2957                 }
2958
2959                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2960                         clear_port_feature(hub->hdev, port1,
2961                                         USB_PORT_FEAT_C_CONNECTION);
2962                 }
2963
2964                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2965                         break;
2966                 msleep(HUB_DEBOUNCE_STEP);
2967         }
2968
2969         dev_dbg (hub->intfdev,
2970                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2971                 port1, total_time, stable_time, portstatus);
2972
2973         if (stable_time < HUB_DEBOUNCE_STABLE)
2974                 return -ETIMEDOUT;
2975         return portstatus;
2976 }
2977
2978 void usb_ep0_reinit(struct usb_device *udev)
2979 {
2980         usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
2981         usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
2982         usb_enable_endpoint(udev, &udev->ep0, true);
2983 }
2984 EXPORT_SYMBOL_GPL(usb_ep0_reinit);
2985
2986 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2987 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2988
2989 static int hub_set_address(struct usb_device *udev, int devnum)
2990 {
2991         int retval;
2992         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2993
2994         /*
2995          * The host controller will choose the device address,
2996          * instead of the core having chosen it earlier
2997          */
2998         if (!hcd->driver->address_device && devnum <= 1)
2999                 return -EINVAL;
3000         if (udev->state == USB_STATE_ADDRESS)
3001                 return 0;
3002         if (udev->state != USB_STATE_DEFAULT)
3003                 return -EINVAL;
3004         if (hcd->driver->address_device)
3005                 retval = hcd->driver->address_device(hcd, udev);
3006         else
3007                 retval = usb_control_msg(udev, usb_sndaddr0pipe(),
3008                                 USB_REQ_SET_ADDRESS, 0, devnum, 0,
3009                                 NULL, 0, USB_CTRL_SET_TIMEOUT);
3010         if (retval == 0) {
3011                 update_devnum(udev, devnum);
3012                 /* Device now using proper address. */
3013                 usb_set_device_state(udev, USB_STATE_ADDRESS);
3014                 usb_ep0_reinit(udev);
3015         }
3016         return retval;
3017 }
3018
3019 /* Reset device, (re)assign address, get device descriptor.
3020  * Device connection must be stable, no more debouncing needed.
3021  * Returns device in USB_STATE_ADDRESS, except on error.
3022  *
3023  * If this is called for an already-existing device (as part of
3024  * usb_reset_and_verify_device), the caller must own the device lock.  For a
3025  * newly detected device that is not accessible through any global
3026  * pointers, it's not necessary to lock the device.
3027  */
3028 static int
3029 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
3030                 int retry_counter)
3031 {
3032         static DEFINE_MUTEX(usb_address0_mutex);
3033
3034         struct usb_device       *hdev = hub->hdev;
3035         struct usb_hcd          *hcd = bus_to_hcd(hdev->bus);
3036         int                     i, j, retval;
3037         unsigned                delay = HUB_SHORT_RESET_TIME;
3038         enum usb_device_speed   oldspeed = udev->speed;
3039         const char              *speed;
3040         int                     devnum = udev->devnum;
3041
3042         /* root hub ports have a slightly longer reset period
3043          * (from USB 2.0 spec, section 7.1.7.5)
3044          */
3045         if (!hdev->parent) {
3046                 delay = HUB_ROOT_RESET_TIME;
3047                 if (port1 == hdev->bus->otg_port)
3048                         hdev->bus->b_hnp_enable = 0;
3049         }
3050
3051         /* Some low speed devices have problems with the quick delay, so */
3052         /*  be a bit pessimistic with those devices. RHbug #23670 */
3053         if (oldspeed == USB_SPEED_LOW)
3054                 delay = HUB_LONG_RESET_TIME;
3055
3056         mutex_lock(&usb_address0_mutex);
3057
3058         /* Reset the device; full speed may morph to high speed */