usb: pm: disbale autosuspend in default mode
[sitara-epos/sitara-epos-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  */
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>
28 #include <asm/uaccess.h>
29 #include <asm/byteorder.h>
31 #include "usb.h"
33 /* if we are in debug mode, always announce new devices */
34 #ifdef DEBUG
35 #ifndef CONFIG_USB_ANNOUNCE_NEW_DEVICES
36 #define CONFIG_USB_ANNOUNCE_NEW_DEVICES
37 #endif
38 #endif
40 struct usb_hub {
41         struct device           *intfdev;       /* the "interface" device */
42         struct usb_device       *hdev;
43         struct kref             kref;
44         struct urb              *urb;           /* for interrupt polling pipe */
46         /* buffer for urb ... with extra space in case of babble */
47         char                    (*buffer)[8];
48         union {
49                 struct usb_hub_status   hub;
50                 struct usb_port_status  port;
51         }                       *status;        /* buffer for status reports */
52         struct mutex            status_mutex;   /* for the status buffer */
54         int                     error;          /* last reported error */
55         int                     nerrors;        /* track consecutive errors */
57         struct list_head        event_list;     /* hubs w/data or errs ready */
58         unsigned long           event_bits[1];  /* status change bitmask */
59         unsigned long           change_bits[1]; /* ports with logical connect
60                                                         status change */
61         unsigned long           busy_bits[1];   /* ports being reset or
62                                                         resumed */
63         unsigned long           removed_bits[1]; /* ports with a "removed"
64                                                         device present */
65 #if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
66 #error event_bits[] is too short!
67 #endif
69         struct usb_hub_descriptor *descriptor;  /* class descriptor */
70         struct usb_tt           tt;             /* Transaction Translator */
72         unsigned                mA_per_port;    /* current for each child */
74         unsigned                limited_power:1;
75         unsigned                quiescing:1;
76         unsigned                disconnected:1;
78         unsigned                has_indicators:1;
79         u8                      indicator[USB_MAXCHILDREN];
80         struct delayed_work     leds;
81         struct delayed_work     init_work;
82         void                    **port_owners;
83 };
85 static inline int hub_is_superspeed(struct usb_device *hdev)
86 {
87         return (hdev->descriptor.bDeviceProtocol == 3);
88 }
90 /* Protect struct usb_device->state and ->children members
91  * Note: Both are also protected by ->dev.sem, except that ->state can
92  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
93 static DEFINE_SPINLOCK(device_state_lock);
95 /* khubd's worklist and its lock */
96 static DEFINE_SPINLOCK(hub_event_lock);
97 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
99 /* Wakes up khubd */
100 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
102 static struct task_struct *khubd_task;
104 /* cycle leds on hubs that aren't blinking for attention */
105 static int blinkenlights = 0;
106 module_param (blinkenlights, bool, S_IRUGO);
107 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
109 /*
110  * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
111  * 10 seconds to send reply for the initial 64-byte descriptor request.
112  */
113 /* define initial 64-byte descriptor request timeout in milliseconds */
114 static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
115 module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
116 MODULE_PARM_DESC(initial_descriptor_timeout,
117                 "initial 64-byte descriptor request timeout in milliseconds "
118                 "(default 5000 - 5.0 seconds)");
120 /*
121  * As of 2.6.10 we introduce a new USB device initialization scheme which
122  * closely resembles the way Windows works.  Hopefully it will be compatible
123  * with a wider range of devices than the old scheme.  However some previously
124  * working devices may start giving rise to "device not accepting address"
125  * errors; if that happens the user can try the old scheme by adjusting the
126  * following module parameters.
127  *
128  * For maximum flexibility there are two boolean parameters to control the
129  * hub driver's behavior.  On the first initialization attempt, if the
130  * "old_scheme_first" parameter is set then the old scheme will be used,
131  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
132  * is set, then the driver will make another attempt, using the other scheme.
133  */
134 static int old_scheme_first = 0;
135 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
136 MODULE_PARM_DESC(old_scheme_first,
137                  "start with the old device initialization scheme");
139 static int use_both_schemes = 1;
140 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
141 MODULE_PARM_DESC(use_both_schemes,
142                 "try the other device initialization scheme if the "
143                 "first one fails");
145 /* Mutual exclusion for EHCI CF initialization.  This interferes with
146  * port reset on some companion controllers.
147  */
148 DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
149 EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
151 #define HUB_DEBOUNCE_TIMEOUT    1500
152 #define HUB_DEBOUNCE_STEP         25
153 #define HUB_DEBOUNCE_STABLE      100
156 static int usb_reset_and_verify_device(struct usb_device *udev);
158 static inline char *portspeed(struct usb_hub *hub, int portstatus)
160         if (hub_is_superspeed(hub->hdev))
161                 return "5.0 Gb/s";
162         if (portstatus & USB_PORT_STAT_HIGH_SPEED)
163                 return "480 Mb/s";
164         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
165                 return "1.5 Mb/s";
166         else
167                 return "12 Mb/s";
170 /* Note that hdev or one of its children must be locked! */
171 static struct usb_hub *hdev_to_hub(struct usb_device *hdev)
173         if (!hdev || !hdev->actconfig)
174                 return NULL;
175         return usb_get_intfdata(hdev->actconfig->interface[0]);
178 /* USB 2.0 spec Section 11.24.4.5 */
179 static int get_hub_descriptor(struct usb_device *hdev, void *data)
181         int i, ret, size;
182         unsigned dtype;
184         if (hub_is_superspeed(hdev)) {
185                 dtype = USB_DT_SS_HUB;
186                 size = USB_DT_SS_HUB_SIZE;
187         } else {
188                 dtype = USB_DT_HUB;
189                 size = sizeof(struct usb_hub_descriptor);
190         }
192         for (i = 0; i < 3; i++) {
193                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
194                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
195                         dtype << 8, 0, data, size,
196                         USB_CTRL_GET_TIMEOUT);
197                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
198                         return ret;
199         }
200         return -EINVAL;
203 /*
204  * USB 2.0 spec Section 11.24.2.1
205  */
206 static int clear_hub_feature(struct usb_device *hdev, int feature)
208         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
209                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
212 /*
213  * USB 2.0 spec Section 11.24.2.2
214  */
215 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
217         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
218                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
219                 NULL, 0, 1000);
222 /*
223  * USB 2.0 spec Section 11.24.2.13
224  */
225 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
227         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
228                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
229                 NULL, 0, 1000);
232 /*
233  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
234  * for info about using port indicators
235  */
236 static void set_port_led(
237         struct usb_hub *hub,
238         int port1,
239         int selector
242         int status = set_port_feature(hub->hdev, (selector << 8) | port1,
243                         USB_PORT_FEAT_INDICATOR);
244         if (status < 0)
245                 dev_dbg (hub->intfdev,
246                         "port %d indicator %s status %d\n",
247                         port1,
248                         ({ char *s; switch (selector) {
249                         case HUB_LED_AMBER: s = "amber"; break;
250                         case HUB_LED_GREEN: s = "green"; break;
251                         case HUB_LED_OFF: s = "off"; break;
252                         case HUB_LED_AUTO: s = "auto"; break;
253                         default: s = "??"; break;
254                         }; s; }),
255                         status);
258 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
260 static void led_work (struct work_struct *work)
262         struct usb_hub          *hub =
263                 container_of(work, struct usb_hub, leds.work);
264         struct usb_device       *hdev = hub->hdev;
265         unsigned                i;
266         unsigned                changed = 0;
267         int                     cursor = -1;
269         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
270                 return;
272         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
273                 unsigned        selector, mode;
275                 /* 30%-50% duty cycle */
277                 switch (hub->indicator[i]) {
278                 /* cycle marker */
279                 case INDICATOR_CYCLE:
280                         cursor = i;
281                         selector = HUB_LED_AUTO;
282                         mode = INDICATOR_AUTO;
283                         break;
284                 /* blinking green = sw attention */
285                 case INDICATOR_GREEN_BLINK:
286                         selector = HUB_LED_GREEN;
287                         mode = INDICATOR_GREEN_BLINK_OFF;
288                         break;
289                 case INDICATOR_GREEN_BLINK_OFF:
290                         selector = HUB_LED_OFF;
291                         mode = INDICATOR_GREEN_BLINK;
292                         break;
293                 /* blinking amber = hw attention */
294                 case INDICATOR_AMBER_BLINK:
295                         selector = HUB_LED_AMBER;
296                         mode = INDICATOR_AMBER_BLINK_OFF;
297                         break;
298                 case INDICATOR_AMBER_BLINK_OFF:
299                         selector = HUB_LED_OFF;
300                         mode = INDICATOR_AMBER_BLINK;
301                         break;
302                 /* blink green/amber = reserved */
303                 case INDICATOR_ALT_BLINK:
304                         selector = HUB_LED_GREEN;
305                         mode = INDICATOR_ALT_BLINK_OFF;
306                         break;
307                 case INDICATOR_ALT_BLINK_OFF:
308                         selector = HUB_LED_AMBER;
309                         mode = INDICATOR_ALT_BLINK;
310                         break;
311                 default:
312                         continue;
313                 }
314                 if (selector != HUB_LED_AUTO)
315                         changed = 1;
316                 set_port_led(hub, i + 1, selector);
317                 hub->indicator[i] = mode;
318         }
319         if (!changed && blinkenlights) {
320                 cursor++;
321                 cursor %= hub->descriptor->bNbrPorts;
322                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
323                 hub->indicator[cursor] = INDICATOR_CYCLE;
324                 changed++;
325         }
326         if (changed)
327                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
330 /* use a short timeout for hub/port status fetches */
331 #define USB_STS_TIMEOUT         1000
332 #define USB_STS_RETRIES         5
334 /*
335  * USB 2.0 spec Section 11.24.2.6
336  */
337 static int get_hub_status(struct usb_device *hdev,
338                 struct usb_hub_status *data)
340         int i, status = -ETIMEDOUT;
342         for (i = 0; i < USB_STS_RETRIES &&
343                         (status == -ETIMEDOUT || status == -EPIPE); i++) {
344                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
345                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
346                         data, sizeof(*data), USB_STS_TIMEOUT);
347         }
348         return status;
351 /*
352  * USB 2.0 spec Section 11.24.2.7
353  */
354 static int get_port_status(struct usb_device *hdev, int port1,
355                 struct usb_port_status *data)
357         int i, status = -ETIMEDOUT;
359         for (i = 0; i < USB_STS_RETRIES &&
360                         (status == -ETIMEDOUT || status == -EPIPE); i++) {
361                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
362                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
363                         data, sizeof(*data), USB_STS_TIMEOUT);
364         }
365         return status;
368 static int hub_port_status(struct usb_hub *hub, int port1,
369                 u16 *status, u16 *change)
371         int ret;
373         mutex_lock(&hub->status_mutex);
374         ret = get_port_status(hub->hdev, port1, &hub->status->port);
375         if (ret < 4) {
376                 dev_err(hub->intfdev,
377                         "%s failed (err = %d)\n", __func__, ret);
378                 if (ret >= 0)
379                         ret = -EIO;
380         } else {
381                 *status = le16_to_cpu(hub->status->port.wPortStatus);
382                 *change = le16_to_cpu(hub->status->port.wPortChange);
384                 ret = 0;
385         }
386         mutex_unlock(&hub->status_mutex);
387         return ret;
390 static void kick_khubd(struct usb_hub *hub)
392         unsigned long   flags;
394         spin_lock_irqsave(&hub_event_lock, flags);
395         if (!hub->disconnected && list_empty(&hub->event_list)) {
396                 list_add_tail(&hub->event_list, &hub_event_list);
398                 /* Suppress autosuspend until khubd runs */
399                 usb_autopm_get_interface_no_resume(
400                                 to_usb_interface(hub->intfdev));
401                 wake_up(&khubd_wait);
402         }
403         spin_unlock_irqrestore(&hub_event_lock, flags);
406 void usb_kick_khubd(struct usb_device *hdev)
408         struct usb_hub *hub = hdev_to_hub(hdev);
410         if (hub)
411                 kick_khubd(hub);
415 /* completion function, fires on port status changes and various faults */
416 static void hub_irq(struct urb *urb)
418         struct usb_hub *hub = urb->context;
419         int status = urb->status;
420         unsigned i;
421         unsigned long bits;
423         switch (status) {
424         case -ENOENT:           /* synchronous unlink */
425         case -ECONNRESET:       /* async unlink */
426         case -ESHUTDOWN:        /* hardware going away */
427                 return;
429         default:                /* presumably an error */
430                 /* Cause a hub reset after 10 consecutive errors */
431                 dev_dbg (hub->intfdev, "transfer --> %d\n", status);
432                 if ((++hub->nerrors < 10) || hub->error)
433                         goto resubmit;
434                 hub->error = status;
435                 /* FALL THROUGH */
437         /* let khubd handle things */
438         case 0:                 /* we got data:  port status changed */
439                 bits = 0;
440                 for (i = 0; i < urb->actual_length; ++i)
441                         bits |= ((unsigned long) ((*hub->buffer)[i]))
442                                         << (i*8);
443                 hub->event_bits[0] = bits;
444                 break;
445         }
447         hub->nerrors = 0;
449         /* Something happened, let khubd figure it out */
450         kick_khubd(hub);
452 resubmit:
453         if (hub->quiescing)
454                 return;
456         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
457                         && status != -ENODEV && status != -EPERM)
458                 dev_err (hub->intfdev, "resubmit --> %d\n", status);
461 /* USB 2.0 spec Section 11.24.2.3 */
462 static inline int
463 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
465         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
466                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
467                                tt, NULL, 0, 1000);
470 /*
471  * enumeration blocks khubd for a long time. we use keventd instead, since
472  * long blocking there is the exception, not the rule.  accordingly, HCDs
473  * talking to TTs must queue control transfers (not just bulk and iso), so
474  * both can talk to the same hub concurrently.
475  */
476 static void hub_tt_work(struct work_struct *work)
478         struct usb_hub          *hub =
479                 container_of(work, struct usb_hub, tt.clear_work);
480         unsigned long           flags;
481         int                     limit = 100;
483         spin_lock_irqsave (&hub->tt.lock, flags);
484         while (--limit && !list_empty (&hub->tt.clear_list)) {
485                 struct list_head        *next;
486                 struct usb_tt_clear     *clear;
487                 struct usb_device       *hdev = hub->hdev;
488                 const struct hc_driver  *drv;
489                 int                     status;
491                 next = hub->tt.clear_list.next;
492                 clear = list_entry (next, struct usb_tt_clear, clear_list);
493                 list_del (&clear->clear_list);
495                 /* drop lock so HCD can concurrently report other TT errors */
496                 spin_unlock_irqrestore (&hub->tt.lock, flags);
497                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
498                 if (status)
499                         dev_err (&hdev->dev,
500                                 "clear tt %d (%04x) error %d\n",
501                                 clear->tt, clear->devinfo, status);
503                 /* Tell the HCD, even if the operation failed */
504                 drv = clear->hcd->driver;
505                 if (drv->clear_tt_buffer_complete)
506                         (drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
508                 kfree(clear);
509                 spin_lock_irqsave(&hub->tt.lock, flags);
510         }
511         spin_unlock_irqrestore (&hub->tt.lock, flags);
514 /**
515  * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
516  * @urb: an URB associated with the failed or incomplete split transaction
517  *
518  * High speed HCDs use this to tell the hub driver that some split control or
519  * bulk transaction failed in a way that requires clearing internal state of
520  * a transaction translator.  This is normally detected (and reported) from
521  * interrupt context.
522  *
523  * It may not be possible for that hub to handle additional full (or low)
524  * speed transactions until that state is fully cleared out.
525  */
526 int usb_hub_clear_tt_buffer(struct urb *urb)
528         struct usb_device       *udev = urb->dev;
529         int                     pipe = urb->pipe;
530         struct usb_tt           *tt = udev->tt;
531         unsigned long           flags;
532         struct usb_tt_clear     *clear;
534         /* we've got to cope with an arbitrary number of pending TT clears,
535          * since each TT has "at least two" buffers that can need it (and
536          * there can be many TTs per hub).  even if they're uncommon.
537          */
538         if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
539                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
540                 /* FIXME recover somehow ... RESET_TT? */
541                 return -ENOMEM;
542         }
544         /* info that CLEAR_TT_BUFFER needs */
545         clear->tt = tt->multi ? udev->ttport : 1;
546         clear->devinfo = usb_pipeendpoint (pipe);
547         clear->devinfo |= udev->devnum << 4;
548         clear->devinfo |= usb_pipecontrol (pipe)
549                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
550                         : (USB_ENDPOINT_XFER_BULK << 11);
551         if (usb_pipein (pipe))
552                 clear->devinfo |= 1 << 15;
554         /* info for completion callback */
555         clear->hcd = bus_to_hcd(udev->bus);
556         clear->ep = urb->ep;
558         /* tell keventd to clear state for this TT */
559         spin_lock_irqsave (&tt->lock, flags);
560         list_add_tail (&clear->clear_list, &tt->clear_list);
561         schedule_work(&tt->clear_work);
562         spin_unlock_irqrestore (&tt->lock, flags);
563         return 0;
565 EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
567 /* If do_delay is false, return the number of milliseconds the caller
568  * needs to delay.
569  */
570 static unsigned hub_power_on(struct usb_hub *hub, bool do_delay)
572         int port1;
573         unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
574         unsigned delay;
575         u16 wHubCharacteristics =
576                         le16_to_cpu(hub->descriptor->wHubCharacteristics);
578         /* Enable power on each port.  Some hubs have reserved values
579          * of LPSM (> 2) in their descriptors, even though they are
580          * USB 2.0 hubs.  Some hubs do not implement port-power switching
581          * but only emulate it.  In all cases, the ports won't work
582          * unless we send these messages to the hub.
583          */
584         if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2)
585                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
586         else
587                 dev_dbg(hub->intfdev, "trying to enable port power on "
588                                 "non-switchable hub\n");
589         for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
590                 set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
592         /* Wait at least 100 msec for power to become stable */
593         delay = max(pgood_delay, (unsigned) 100);
594         if (do_delay)
595                 msleep(delay);
596         return delay;
599 static int hub_hub_status(struct usb_hub *hub,
600                 u16 *status, u16 *change)
602         int ret;
604         mutex_lock(&hub->status_mutex);
605         ret = get_hub_status(hub->hdev, &hub->status->hub);
606         if (ret < 0)
607                 dev_err (hub->intfdev,
608                         "%s failed (err = %d)\n", __func__, ret);
609         else {
610                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
611                 *change = le16_to_cpu(hub->status->hub.wHubChange); 
612                 ret = 0;
613         }
614         mutex_unlock(&hub->status_mutex);
615         return ret;
618 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
620         struct usb_device *hdev = hub->hdev;
621         int ret = 0;
623         if (hdev->children[port1-1] && set_state)
624                 usb_set_device_state(hdev->children[port1-1],
625                                 USB_STATE_NOTATTACHED);
626         if (!hub->error && !hub_is_superspeed(hub->hdev))
627                 ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
628         if (ret)
629                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
630                                 port1, ret);
631         return ret;
634 /*
635  * Disable a port and mark a logical connect-change event, so that some
636  * time later khubd will disconnect() any existing usb_device on the port
637  * and will re-enumerate if there actually is a device attached.
638  */
639 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
641         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
642         hub_port_disable(hub, port1, 1);
644         /* FIXME let caller ask to power down the port:
645          *  - some devices won't enumerate without a VBUS power cycle
646          *  - SRP saves power that way
647          *  - ... new call, TBD ...
648          * That's easy if this hub can switch power per-port, and
649          * khubd reactivates the port later (timer, SRP, etc).
650          * Powerdown must be optional, because of reset/DFU.
651          */
653         set_bit(port1, hub->change_bits);
654         kick_khubd(hub);
657 /**
658  * usb_remove_device - disable a device's port on its parent hub
659  * @udev: device to be disabled and removed
660  * Context: @udev locked, must be able to sleep.
661  *
662  * After @udev's port has been disabled, khubd is notified and it will
663  * see that the device has been disconnected.  When the device is
664  * physically unplugged and something is plugged in, the events will
665  * be received and processed normally.
666  */
667 int usb_remove_device(struct usb_device *udev)
669         struct usb_hub *hub;
670         struct usb_interface *intf;
672         if (!udev->parent)      /* Can't remove a root hub */
673                 return -EINVAL;
674         hub = hdev_to_hub(udev->parent);
675         intf = to_usb_interface(hub->intfdev);
677         usb_autopm_get_interface(intf);
678         set_bit(udev->portnum, hub->removed_bits);
679         hub_port_logical_disconnect(hub, udev->portnum);
680         usb_autopm_put_interface(intf);
681         return 0;
684 enum hub_activation_type {
685         HUB_INIT, HUB_INIT2, HUB_INIT3,         /* INITs must come first */
686         HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
687 };
689 static void hub_init_func2(struct work_struct *ws);
690 static void hub_init_func3(struct work_struct *ws);
692 static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
694         struct usb_device *hdev = hub->hdev;
695         struct usb_hcd *hcd;
696         int ret;
697         int port1;
698         int status;
699         bool need_debounce_delay = false;
700         unsigned delay;
702         /* Continue a partial initialization */
703         if (type == HUB_INIT2)
704                 goto init2;
705         if (type == HUB_INIT3)
706                 goto init3;
708         /* After a resume, port power should still be on.
709          * For any other type of activation, turn it on.
710          */
711         if (type != HUB_RESUME) {
713                 /* Speed up system boot by using a delayed_work for the
714                  * hub's initial power-up delays.  This is pretty awkward
715                  * and the implementation looks like a home-brewed sort of
716                  * setjmp/longjmp, but it saves at least 100 ms for each
717                  * root hub (assuming usbcore is compiled into the kernel
718                  * rather than as a module).  It adds up.
719                  *
720                  * This can't be done for HUB_RESUME or HUB_RESET_RESUME
721                  * because for those activation types the ports have to be
722                  * operational when we return.  In theory this could be done
723                  * for HUB_POST_RESET, but it's easier not to.
724                  */
725                 if (type == HUB_INIT) {
726                         delay = hub_power_on(hub, false);
727                         PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func2);
728                         schedule_delayed_work(&hub->init_work,
729                                         msecs_to_jiffies(delay));
731                         /* Suppress autosuspend until init is done */
732                         usb_autopm_get_interface_no_resume(
733                                         to_usb_interface(hub->intfdev));
734                         return;         /* Continues at init2: below */
735                 } else if (type == HUB_RESET_RESUME) {
736                         /* The internal host controller state for the hub device
737                          * may be gone after a host power loss on system resume.
738                          * Update the device's info so the HW knows it's a hub.
739                          */
740                         hcd = bus_to_hcd(hdev->bus);
741                         if (hcd->driver->update_hub_device) {
742                                 ret = hcd->driver->update_hub_device(hcd, hdev,
743                                                 &hub->tt, GFP_NOIO);
744                                 if (ret < 0) {
745                                         dev_err(hub->intfdev, "Host not "
746                                                         "accepting hub info "
747                                                         "update.\n");
748                                         dev_err(hub->intfdev, "LS/FS devices "
749                                                         "and hubs may not work "
750                                                         "under this hub\n.");
751                                 }
752                         }
753                         hub_power_on(hub, true);
754                 } else {
755                         hub_power_on(hub, true);
756                 }
757         }
758  init2:
760         /* Check each port and set hub->change_bits to let khubd know
761          * which ports need attention.
762          */
763         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
764                 struct usb_device *udev = hdev->children[port1-1];
765                 u16 portstatus, portchange;
767                 portstatus = portchange = 0;
768                 status = hub_port_status(hub, port1, &portstatus, &portchange);
769                 if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
770                         dev_dbg(hub->intfdev,
771                                         "port %d: status %04x change %04x\n",
772                                         port1, portstatus, portchange);
774                 /* After anything other than HUB_RESUME (i.e., initialization
775                  * or any sort of reset), every port should be disabled.
776                  * Unconnected ports should likewise be disabled (paranoia),
777                  * and so should ports for which we have no usb_device.
778                  */
779                 if ((portstatus & USB_PORT_STAT_ENABLE) && (
780                                 type != HUB_RESUME ||
781                                 !(portstatus & USB_PORT_STAT_CONNECTION) ||
782                                 !udev ||
783                                 udev->state == USB_STATE_NOTATTACHED)) {
784                         /*
785                          * USB3 protocol ports will automatically transition
786                          * to Enabled state when detect an USB3.0 device attach.
787                          * Do not disable USB3 protocol ports.
788                          */
789                         if (!hub_is_superspeed(hdev)) {
790                                 clear_port_feature(hdev, port1,
791                                                    USB_PORT_FEAT_ENABLE);
792                                 portstatus &= ~USB_PORT_STAT_ENABLE;
793                         } else {
794                                 /* Pretend that power was lost for USB3 devs */
795                                 portstatus &= ~USB_PORT_STAT_ENABLE;
796                         }
797                 }
799                 /* Clear status-change flags; we'll debounce later */
800                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
801                         need_debounce_delay = true;
802                         clear_port_feature(hub->hdev, port1,
803                                         USB_PORT_FEAT_C_CONNECTION);
804                 }
805                 if (portchange & USB_PORT_STAT_C_ENABLE) {
806                         need_debounce_delay = true;
807                         clear_port_feature(hub->hdev, port1,
808                                         USB_PORT_FEAT_C_ENABLE);
809                 }
810                 if (portchange & USB_PORT_STAT_C_LINK_STATE) {
811                         need_debounce_delay = true;
812                         clear_port_feature(hub->hdev, port1,
813                                         USB_PORT_FEAT_C_PORT_LINK_STATE);
814                 }
816                 if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
817                                 hub_is_superspeed(hub->hdev)) {
818                         need_debounce_delay = true;
819                         clear_port_feature(hub->hdev, port1,
820                                         USB_PORT_FEAT_C_BH_PORT_RESET);
821                 }
822                 /* We can forget about a "removed" device when there's a
823                  * physical disconnect or the connect status changes.
824                  */
825                 if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
826                                 (portchange & USB_PORT_STAT_C_CONNECTION))
827                         clear_bit(port1, hub->removed_bits);
829                 if (!udev || udev->state == USB_STATE_NOTATTACHED) {
830                         /* Tell khubd to disconnect the device or
831                          * check for a new connection
832                          */
833                         if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
834                                 set_bit(port1, hub->change_bits);
836                 } else if (portstatus & USB_PORT_STAT_ENABLE) {
837                         /* The power session apparently survived the resume.
838                          * If there was an overcurrent or suspend change
839                          * (i.e., remote wakeup request), have khubd
840                          * take care of it.
841                          */
842                         if (portchange)
843                                 set_bit(port1, hub->change_bits);
845                 } else if (udev->persist_enabled) {
846 #ifdef CONFIG_PM
847                         udev->reset_resume = 1;
848 #endif
849                         set_bit(port1, hub->change_bits);
851                 } else {
852                         /* The power session is gone; tell khubd */
853                         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
854                         set_bit(port1, hub->change_bits);
855                 }
856         }
858         /* If no port-status-change flags were set, we don't need any
859          * debouncing.  If flags were set we can try to debounce the
860          * ports all at once right now, instead of letting khubd do them
861          * one at a time later on.
862          *
863          * If any port-status changes do occur during this delay, khubd
864          * will see them later and handle them normally.
865          */
866         if (need_debounce_delay) {
867                 delay = HUB_DEBOUNCE_STABLE;
869                 /* Don't do a long sleep inside a workqueue routine */
870                 if (type == HUB_INIT2) {
871                         PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func3);
872                         schedule_delayed_work(&hub->init_work,
873                                         msecs_to_jiffies(delay));
874                         return;         /* Continues at init3: below */
875                 } else {
876                         msleep(delay);
877                 }
878         }
879  init3:
880         hub->quiescing = 0;
882         status = usb_submit_urb(hub->urb, GFP_NOIO);
883         if (status < 0)
884                 dev_err(hub->intfdev, "activate --> %d\n", status);
885         if (hub->has_indicators && blinkenlights)
886                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
888         /* Scan all ports that need attention */
889         kick_khubd(hub);
891         /* Allow autosuspend if it was suppressed */
892         if (type <= HUB_INIT3)
893                 usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
896 /* Implement the continuations for the delays above */
897 static void hub_init_func2(struct work_struct *ws)
899         struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
901         hub_activate(hub, HUB_INIT2);
904 static void hub_init_func3(struct work_struct *ws)
906         struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
908         hub_activate(hub, HUB_INIT3);
911 enum hub_quiescing_type {
912         HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
913 };
915 static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
917         struct usb_device *hdev = hub->hdev;
918         int i;
920         cancel_delayed_work_sync(&hub->init_work);
922         /* khubd and related activity won't re-trigger */
923         hub->quiescing = 1;
925         if (type != HUB_SUSPEND) {
926                 /* Disconnect all the children */
927                 for (i = 0; i < hdev->maxchild; ++i) {
928                         if (hdev->children[i])
929                                 usb_disconnect(&hdev->children[i]);
930                 }
931         }
933         /* Stop khubd and related activity */
934         usb_kill_urb(hub->urb);
935         if (hub->has_indicators)
936                 cancel_delayed_work_sync(&hub->leds);
937         if (hub->tt.hub)
938                 cancel_work_sync(&hub->tt.clear_work);
941 /* caller has locked the hub device */
942 static int hub_pre_reset(struct usb_interface *intf)
944         struct usb_hub *hub = usb_get_intfdata(intf);
946         hub_quiesce(hub, HUB_PRE_RESET);
947         return 0;
950 /* caller has locked the hub device */
951 static int hub_post_reset(struct usb_interface *intf)
953         struct usb_hub *hub = usb_get_intfdata(intf);
955         hub_activate(hub, HUB_POST_RESET);
956         return 0;
959 static int hub_configure(struct usb_hub *hub,
960         struct usb_endpoint_descriptor *endpoint)
962         struct usb_hcd *hcd;
963         struct usb_device *hdev = hub->hdev;
964         struct device *hub_dev = hub->intfdev;
965         u16 hubstatus, hubchange;
966         u16 wHubCharacteristics;
967         unsigned int pipe;
968         int maxp, ret;
969         char *message = "out of memory";
971         hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
972         if (!hub->buffer) {
973                 ret = -ENOMEM;
974                 goto fail;
975         }
977         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
978         if (!hub->status) {
979                 ret = -ENOMEM;
980                 goto fail;
981         }
982         mutex_init(&hub->status_mutex);
984         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
985         if (!hub->descriptor) {
986                 ret = -ENOMEM;
987                 goto fail;
988         }
990         if (hub_is_superspeed(hdev) && (hdev->parent != NULL)) {
991                 ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
992                                 HUB_SET_DEPTH, USB_RT_HUB,
993                                 hdev->level - 1, 0, NULL, 0,
994                                 USB_CTRL_SET_TIMEOUT);
996                 if (ret < 0) {
997                         message = "can't set hub depth";
998                         goto fail;
999                 }
1000         }
1002         /* Request the entire hub descriptor.
1003          * hub->descriptor can handle USB_MAXCHILDREN ports,
1004          * but the hub can/will return fewer bytes here.
1005          */
1006         ret = get_hub_descriptor(hdev, hub->descriptor);
1007         if (ret < 0) {
1008                 message = "can't read hub descriptor";
1009                 goto fail;
1010         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
1011                 message = "hub has too many ports!";
1012                 ret = -ENODEV;
1013                 goto fail;
1014         }
1016         hdev->maxchild = hub->descriptor->bNbrPorts;
1017         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
1018                 (hdev->maxchild == 1) ? "" : "s");
1020         hub->port_owners = kzalloc(hdev->maxchild * sizeof(void *), GFP_KERNEL);
1021         if (!hub->port_owners) {
1022                 ret = -ENOMEM;
1023                 goto fail;
1024         }
1026         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1028         /* FIXME for USB 3.0, skip for now */
1029         if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
1030                         !(hub_is_superspeed(hdev))) {
1031                 int     i;
1032                 char    portstr [USB_MAXCHILDREN + 1];
1034                 for (i = 0; i < hdev->maxchild; i++)
1035                         portstr[i] = hub->descriptor->u.hs.DeviceRemovable
1036                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
1037                                 ? 'F' : 'R';
1038                 portstr[hdev->maxchild] = 0;
1039                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
1040         } else
1041                 dev_dbg(hub_dev, "standalone hub\n");
1043         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1044                 case 0x00:
1045                         dev_dbg(hub_dev, "ganged power switching\n");
1046                         break;
1047                 case 0x01:
1048                         dev_dbg(hub_dev, "individual port power switching\n");
1049                         break;
1050                 case 0x02:
1051                 case 0x03:
1052                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
1053                         break;
1054         }
1056         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1057                 case 0x00:
1058                         dev_dbg(hub_dev, "global over-current protection\n");
1059                         break;
1060                 case 0x08:
1061                         dev_dbg(hub_dev, "individual port over-current protection\n");
1062                         break;
1063                 case 0x10:
1064                 case 0x18:
1065                         dev_dbg(hub_dev, "no over-current protection\n");
1066                         break;
1067         }
1069         spin_lock_init (&hub->tt.lock);
1070         INIT_LIST_HEAD (&hub->tt.clear_list);
1071         INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1072         switch (hdev->descriptor.bDeviceProtocol) {
1073                 case 0:
1074                         break;
1075                 case 1:
1076                         dev_dbg(hub_dev, "Single TT\n");
1077                         hub->tt.hub = hdev;
1078                         break;
1079                 case 2:
1080                         ret = usb_set_interface(hdev, 0, 1);
1081                         if (ret == 0) {
1082                                 dev_dbg(hub_dev, "TT per port\n");
1083                                 hub->tt.multi = 1;
1084                         } else
1085                                 dev_err(hub_dev, "Using single TT (err %d)\n",
1086                                         ret);
1087                         hub->tt.hub = hdev;
1088                         break;
1089                 case 3:
1090                         /* USB 3.0 hubs don't have a TT */
1091                         break;
1092                 default:
1093                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1094                                 hdev->descriptor.bDeviceProtocol);
1095                         break;
1096         }
1098         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1099         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1100                 case HUB_TTTT_8_BITS:
1101                         if (hdev->descriptor.bDeviceProtocol != 0) {
1102                                 hub->tt.think_time = 666;
1103                                 dev_dbg(hub_dev, "TT requires at most %d "
1104                                                 "FS bit times (%d ns)\n",
1105                                         8, hub->tt.think_time);
1106                         }
1107                         break;
1108                 case HUB_TTTT_16_BITS:
1109                         hub->tt.think_time = 666 * 2;
1110                         dev_dbg(hub_dev, "TT requires at most %d "
1111                                         "FS bit times (%d ns)\n",
1112                                 16, hub->tt.think_time);
1113                         break;
1114                 case HUB_TTTT_24_BITS:
1115                         hub->tt.think_time = 666 * 3;
1116                         dev_dbg(hub_dev, "TT requires at most %d "
1117                                         "FS bit times (%d ns)\n",
1118                                 24, hub->tt.think_time);
1119                         break;
1120                 case HUB_TTTT_32_BITS:
1121                         hub->tt.think_time = 666 * 4;
1122                         dev_dbg(hub_dev, "TT requires at most %d "
1123                                         "FS bit times (%d ns)\n",
1124                                 32, hub->tt.think_time);
1125                         break;
1126         }
1128         /* probe() zeroes hub->indicator[] */
1129         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1130                 hub->has_indicators = 1;
1131                 dev_dbg(hub_dev, "Port indicators are supported\n");
1132         }
1134         dev_dbg(hub_dev, "power on to power good time: %dms\n",
1135                 hub->descriptor->bPwrOn2PwrGood * 2);
1137         /* power budgeting mostly matters with bus-powered hubs,
1138          * and battery-powered root hubs (may provide just 8 mA).
1139          */
1140         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1141         if (ret < 2) {
1142                 message = "can't get hub status";
1143                 goto fail;
1144         }
1145         le16_to_cpus(&hubstatus);
1146         if (hdev == hdev->bus->root_hub) {
1147                 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
1148                         hub->mA_per_port = 500;
1149                 else {
1150                         hub->mA_per_port = hdev->bus_mA;
1151                         hub->limited_power = 1;
1152                 }
1153         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1154                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1155                         hub->descriptor->bHubContrCurrent);
1156                 hub->limited_power = 1;
1157                 if (hdev->maxchild > 0) {
1158                         int remaining = hdev->bus_mA -
1159                                         hub->descriptor->bHubContrCurrent;
1161                         if (remaining < hdev->maxchild * 100)
1162                                 dev_warn(hub_dev,
1163                                         "insufficient power available "
1164                                         "to use all downstream ports\n");
1165                         hub->mA_per_port = 100;         /* 7.2.1.1 */
1166                 }
1167         } else {        /* Self-powered external hub */
1168                 /* FIXME: What about battery-powered external hubs that
1169                  * provide less current per port? */
1170                 hub->mA_per_port = 500;
1171         }
1172         if (hub->mA_per_port < 500)
1173                 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1174                                 hub->mA_per_port);
1176         /* Update the HCD's internal representation of this hub before khubd
1177          * starts getting port status changes for devices under the hub.
1178          */
1179         hcd = bus_to_hcd(hdev->bus);
1180         if (hcd->driver->update_hub_device) {
1181                 ret = hcd->driver->update_hub_device(hcd, hdev,
1182                                 &hub->tt, GFP_KERNEL);
1183                 if (ret < 0) {
1184                         message = "can't update HCD hub info";
1185                         goto fail;
1186                 }
1187         }
1189         ret = hub_hub_status(hub, &hubstatus, &hubchange);
1190         if (ret < 0) {
1191                 message = "can't get hub status";
1192                 goto fail;
1193         }
1195         /* local power status reports aren't always correct */
1196         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1197                 dev_dbg(hub_dev, "local power source is %s\n",
1198                         (hubstatus & HUB_STATUS_LOCAL_POWER)
1199                         ? "lost (inactive)" : "good");
1201         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1202                 dev_dbg(hub_dev, "%sover-current condition exists\n",
1203                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1205         /* set up the interrupt endpoint
1206          * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1207          * bytes as USB2.0[11.12.3] says because some hubs are known
1208          * to send more data (and thus cause overflow). For root hubs,
1209          * maxpktsize is defined in hcd.c's fake endpoint descriptors
1210          * to be big enough for at least USB_MAXCHILDREN ports. */
1211         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1212         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
1214         if (maxp > sizeof(*hub->buffer))
1215                 maxp = sizeof(*hub->buffer);
1217         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1218         if (!hub->urb) {
1219                 ret = -ENOMEM;
1220                 goto fail;
1221         }
1223         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1224                 hub, endpoint->bInterval);
1226         /* maybe cycle the hub leds */
1227         if (hub->has_indicators && blinkenlights)
1228                 hub->indicator [0] = INDICATOR_CYCLE;
1230         hub_activate(hub, HUB_INIT);
1231         return 0;
1233 fail:
1234         dev_err (hub_dev, "config failed, %s (err %d)\n",
1235                         message, ret);
1236         /* hub_disconnect() frees urb and descriptor */
1237         return ret;
1240 static void hub_release(struct kref *kref)
1242         struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1244         usb_put_intf(to_usb_interface(hub->intfdev));
1245         kfree(hub);
1248 static unsigned highspeed_hubs;
1250 static void hub_disconnect(struct usb_interface *intf)
1252         struct usb_hub *hub = usb_get_intfdata (intf);
1254         /* Take the hub off the event list and don't let it be added again */
1255         spin_lock_irq(&hub_event_lock);
1256         if (!list_empty(&hub->event_list)) {
1257                 list_del_init(&hub->event_list);
1258                 usb_autopm_put_interface_no_suspend(intf);
1259         }
1260         hub->disconnected = 1;
1261         spin_unlock_irq(&hub_event_lock);
1263         /* Disconnect all children and quiesce the hub */
1264         hub->error = 0;
1265         hub_quiesce(hub, HUB_DISCONNECT);
1267         usb_set_intfdata (intf, NULL);
1268         hub->hdev->maxchild = 0;
1270         if (hub->hdev->speed == USB_SPEED_HIGH)
1271                 highspeed_hubs--;
1273         usb_free_urb(hub->urb);
1274         kfree(hub->port_owners);
1275         kfree(hub->descriptor);
1276         kfree(hub->status);
1277         kfree(hub->buffer);
1279         kref_put(&hub->kref, hub_release);
1282 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1284         struct usb_host_interface *desc;
1285         struct usb_endpoint_descriptor *endpoint;
1286         struct usb_device *hdev;
1287         struct usb_hub *hub;
1289         desc = intf->cur_altsetting;
1290         hdev = interface_to_usbdev(intf);
1292         /* Hubs have proper suspend/resume support.  USB 3.0 device suspend is
1293          * different from USB 2.0/1.1 device suspend, and unfortunately we
1294          * don't support it yet.  So leave autosuspend disabled for USB 3.0
1295          * external hubs for now.  Enable autosuspend for USB 3.0 roothubs,
1296          * since that isn't a "real" hub.
1297          */
1298         if (!hub_is_superspeed(hdev) || !hdev->parent)
1299                 usb_disable_autosuspend(hdev);
1301         if (hdev->level == MAX_TOPO_LEVEL) {
1302                 dev_err(&intf->dev,
1303                         "Unsupported bus topology: hub nested too deep\n");
1304                 return -E2BIG;
1305         }
1307 #ifdef  CONFIG_USB_OTG_BLACKLIST_HUB
1308         if (hdev->parent) {
1309                 dev_warn(&intf->dev, "ignoring external hub\n");
1310                 return -ENODEV;
1311         }
1312 #endif
1314         /* Some hubs have a subclass of 1, which AFAICT according to the */
1315         /*  specs is not defined, but it works */
1316         if ((desc->desc.bInterfaceSubClass != 0) &&
1317             (desc->desc.bInterfaceSubClass != 1)) {
1318 descriptor_error:
1319                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
1320                 return -EIO;
1321         }
1323         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
1324         if (desc->desc.bNumEndpoints != 1)
1325                 goto descriptor_error;
1327         endpoint = &desc->endpoint[0].desc;
1329         /* If it's not an interrupt in endpoint, we'd better punt! */
1330         if (!usb_endpoint_is_int_in(endpoint))
1331                 goto descriptor_error;
1333         /* We found a hub */
1334         dev_info (&intf->dev, "USB hub found\n");
1336         hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1337         if (!hub) {
1338                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
1339                 return -ENOMEM;
1340         }
1342         kref_init(&hub->kref);
1343         INIT_LIST_HEAD(&hub->event_list);
1344         hub->intfdev = &intf->dev;
1345         hub->hdev = hdev;
1346         INIT_DELAYED_WORK(&hub->leds, led_work);
1347         INIT_DELAYED_WORK(&hub->init_work, NULL);
1348         usb_get_intf(intf);
1350         usb_set_intfdata (intf, hub);
1351         intf->needs_remote_wakeup = 1;
1353         if (hdev->speed == USB_SPEED_HIGH)
1354                 highspeed_hubs++;
1356         if (hub_configure(hub, endpoint) >= 0)
1357                 return 0;
1359         hub_disconnect (intf);
1360         return -ENODEV;
1363 /* No BKL needed */
1364 static int
1365 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1367         struct usb_device *hdev = interface_to_usbdev (intf);
1369         /* assert ifno == 0 (part of hub spec) */
1370         switch (code) {
1371         case USBDEVFS_HUB_PORTINFO: {
1372                 struct usbdevfs_hub_portinfo *info = user_data;
1373                 int i;
1375                 spin_lock_irq(&device_state_lock);
1376                 if (hdev->devnum <= 0)
1377                         info->nports = 0;
1378                 else {
1379                         info->nports = hdev->maxchild;
1380                         for (i = 0; i < info->nports; i++) {
1381                                 if (hdev->children[i] == NULL)
1382                                         info->port[i] = 0;
1383                                 else
1384                                         info->port[i] =
1385                                                 hdev->children[i]->devnum;
1386                         }
1387                 }
1388                 spin_unlock_irq(&device_state_lock);
1390                 return info->nports + 1;
1391                 }
1393         default:
1394                 return -ENOSYS;
1395         }
1398 /*
1399  * Allow user programs to claim ports on a hub.  When a device is attached
1400  * to one of these "claimed" ports, the program will "own" the device.
1401  */
1402 static int find_port_owner(struct usb_device *hdev, unsigned port1,
1403                 void ***ppowner)
1405         if (hdev->state == USB_STATE_NOTATTACHED)
1406                 return -ENODEV;
1407         if (port1 == 0 || port1 > hdev->maxchild)
1408                 return -EINVAL;
1410         /* This assumes that devices not managed by the hub driver
1411          * will always have maxchild equal to 0.
1412          */
1413         *ppowner = &(hdev_to_hub(hdev)->port_owners[port1 - 1]);
1414         return 0;
1417 /* In the following three functions, the caller must hold hdev's lock */
1418 int usb_hub_claim_port(struct usb_device *hdev, unsigned port1, void *owner)
1420         int rc;
1421         void **powner;
1423         rc = find_port_owner(hdev, port1, &powner);
1424         if (rc)
1425                 return rc;
1426         if (*powner)
1427                 return -EBUSY;
1428         *powner = owner;
1429         return rc;
1432 int usb_hub_release_port(struct usb_device *hdev, unsigned port1, void *owner)
1434         int rc;
1435         void **powner;
1437         rc = find_port_owner(hdev, port1, &powner);
1438         if (rc)
1439                 return rc;
1440         if (*powner != owner)
1441                 return -ENOENT;
1442         *powner = NULL;
1443         return rc;
1446 void usb_hub_release_all_ports(struct usb_device *hdev, void *owner)
1448         int n;
1449         void **powner;
1451         n = find_port_owner(hdev, 1, &powner);
1452         if (n == 0) {
1453                 for (; n < hdev->maxchild; (++n, ++powner)) {
1454                         if (*powner == owner)
1455                                 *powner = NULL;
1456                 }
1457         }
1460 /* The caller must hold udev's lock */
1461 bool usb_device_is_owned(struct usb_device *udev)
1463         struct usb_hub *hub;
1465         if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
1466                 return false;
1467         hub = hdev_to_hub(udev->parent);
1468         return !!hub->port_owners[udev->portnum - 1];
1472 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
1474         int i;
1476         for (i = 0; i < udev->maxchild; ++i) {
1477                 if (udev->children[i])
1478                         recursively_mark_NOTATTACHED(udev->children[i]);
1479         }
1480         if (udev->state == USB_STATE_SUSPENDED)
1481                 udev->active_duration -= jiffies;
1482         udev->state = USB_STATE_NOTATTACHED;
1485 /**
1486  * usb_set_device_state - change a device's current state (usbcore, hcds)
1487  * @udev: pointer to device whose state should be changed
1488  * @new_state: new state value to be stored
1489  *
1490  * udev->state is _not_ fully protected by the device lock.  Although
1491  * most transitions are made only while holding the lock, the state can
1492  * can change to USB_STATE_NOTATTACHED at almost any time.  This
1493  * is so that devices can be marked as disconnected as soon as possible,
1494  * without having to wait for any semaphores to be released.  As a result,
1495  * all changes to any device's state must be protected by the
1496  * device_state_lock spinlock.
1497  *
1498  * Once a device has been added to the device tree, all changes to its state
1499  * should be made using this routine.  The state should _not_ be set directly.
1500  *
1501  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
1502  * Otherwise udev->state is set to new_state, and if new_state is
1503  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
1504  * to USB_STATE_NOTATTACHED.
1505  */
1506 void usb_set_device_state(struct usb_device *udev,
1507                 enum usb_device_state new_state)
1509         unsigned long flags;
1510         int wakeup = -1;
1512         spin_lock_irqsave(&device_state_lock, flags);
1513         if (udev->state == USB_STATE_NOTATTACHED)
1514                 ;       /* do nothing */
1515         else if (new_state != USB_STATE_NOTATTACHED) {
1517                 /* root hub wakeup capabilities are managed out-of-band
1518                  * and may involve silicon errata ... ignore them here.
1519                  */
1520                 if (udev->parent) {
1521                         if (udev->state == USB_STATE_SUSPENDED
1522                                         || new_state == USB_STATE_SUSPENDED)
1523                                 ;       /* No change to wakeup settings */
1524                         else if (new_state == USB_STATE_CONFIGURED)
1525                                 wakeup = udev->actconfig->desc.bmAttributes
1526                                          & USB_CONFIG_ATT_WAKEUP;
1527                         else
1528                                 wakeup = 0;
1529                 }
1530                 if (udev->state == USB_STATE_SUSPENDED &&
1531                         new_state != USB_STATE_SUSPENDED)
1532                         udev->active_duration -= jiffies;
1533                 else if (new_state == USB_STATE_SUSPENDED &&
1534                                 udev->state != USB_STATE_SUSPENDED)
1535                         udev->active_duration += jiffies;
1536                 udev->state = new_state;
1537         } else
1538                 recursively_mark_NOTATTACHED(udev);
1539         spin_unlock_irqrestore(&device_state_lock, flags);
1540         if (wakeup >= 0)
1541                 device_set_wakeup_capable(&udev->dev, wakeup);
1543 EXPORT_SYMBOL_GPL(usb_set_device_state);
1545 /*
1546  * Choose a device number.
1547  *
1548  * Device numbers are used as filenames in usbfs.  On USB-1.1 and
1549  * USB-2.0 buses they are also used as device addresses, however on
1550  * USB-3.0 buses the address is assigned by the controller hardware
1551  * and it usually is not the same as the device number.
1552  *
1553  * WUSB devices are simple: they have no hubs behind, so the mapping
1554  * device <-> virtual port number becomes 1:1. Why? to simplify the
1555  * life of the device connection logic in
1556  * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
1557  * handshake we need to assign a temporary address in the unauthorized
1558  * space. For simplicity we use the first virtual port number found to
1559  * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
1560  * and that becomes it's address [X < 128] or its unauthorized address
1561  * [X | 0x80].
1562  *
1563  * We add 1 as an offset to the one-based USB-stack port number
1564  * (zero-based wusb virtual port index) for two reasons: (a) dev addr
1565  * 0 is reserved by USB for default address; (b) Linux's USB stack
1566  * uses always #1 for the root hub of the controller. So USB stack's
1567  * port #1, which is wusb virtual-port #0 has address #2.
1568  *
1569  * Devices connected under xHCI are not as simple.  The host controller
1570  * supports virtualization, so the hardware assigns device addresses and
1571  * the HCD must setup data structures before issuing a set address
1572  * command to the hardware.
1573  */
1574 static void choose_devnum(struct usb_device *udev)
1576         int             devnum;
1577         struct usb_bus  *bus = udev->bus;
1579         /* If khubd ever becomes multithreaded, this will need a lock */
1580         if (udev->wusb) {
1581                 devnum = udev->portnum + 1;
1582                 BUG_ON(test_bit(devnum, bus->devmap.devicemap));
1583         } else {
1584                 /* Try to allocate the next devnum beginning at
1585                  * bus->devnum_next. */
1586                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1587                                             bus->devnum_next);
1588                 if (devnum >= 128)
1589                         devnum = find_next_zero_bit(bus->devmap.devicemap,
1590                                                     128, 1);
1591                 bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1592         }
1593         if (devnum < 128) {
1594                 set_bit(devnum, bus->devmap.devicemap);
1595                 udev->devnum = devnum;
1596         }
1599 static void release_devnum(struct usb_device *udev)
1601         if (udev->devnum > 0) {
1602                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1603                 udev->devnum = -1;
1604         }
1607 static void update_devnum(struct usb_device *udev, int devnum)
1609         /* The address for a WUSB device is managed by wusbcore. */
1610         if (!udev->wusb)
1611                 udev->devnum = devnum;
1614 static void hub_free_dev(struct usb_device *udev)
1616         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1618         /* Root hubs aren't real devices, so don't free HCD resources */
1619         if (hcd->driver->free_dev && udev->parent)
1620                 hcd->driver->free_dev(hcd, udev);
1623 /**
1624  * usb_disconnect - disconnect a device (usbcore-internal)
1625  * @pdev: pointer to device being disconnected
1626  * Context: !in_interrupt ()
1627  *
1628  * Something got disconnected. Get rid of it and all of its children.
1629  *
1630  * If *pdev is a normal device then the parent hub must already be locked.
1631  * If *pdev is a root hub then this routine will acquire the
1632  * usb_bus_list_lock on behalf of the caller.
1633  *
1634  * Only hub drivers (including virtual root hub drivers for host
1635  * controllers) should ever call this.
1636  *
1637  * This call is synchronous, and may not be used in an interrupt context.
1638  */
1639 void usb_disconnect(struct usb_device **pdev)
1641         struct usb_device       *udev = *pdev;
1642         int                     i;
1643         struct usb_hcd          *hcd = bus_to_hcd(udev->bus);
1645         /* mark the device as inactive, so any further urb submissions for
1646          * this device (and any of its children) will fail immediately.
1647          * this quiesces everything except pending urbs.
1648          */
1649         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1650         dev_info(&udev->dev, "USB disconnect, device number %d\n",
1651                         udev->devnum);
1653         usb_lock_device(udev);
1655         /* Free up all the children before we remove this device */
1656         for (i = 0; i < USB_MAXCHILDREN; i++) {
1657                 if (udev->children[i])
1658                         usb_disconnect(&udev->children[i]);
1659         }
1661         /* deallocate hcd/hardware state ... nuking all pending urbs and
1662          * cleaning up all state associated with the current configuration
1663          * so that the hardware is now fully quiesced.
1664          */
1665         dev_dbg (&udev->dev, "unregistering device\n");
1666         mutex_lock(hcd->bandwidth_mutex);
1667         usb_disable_device(udev, 0);
1668         mutex_unlock(hcd->bandwidth_mutex);
1669         usb_hcd_synchronize_unlinks(udev);
1671         usb_remove_ep_devs(&udev->ep0);
1672         usb_unlock_device(udev);
1674         /* Unregister the device.  The device driver is responsible
1675          * for de-configuring the device and invoking the remove-device
1676          * notifier chain (used by usbfs and possibly others).
1677          */
1678         device_del(&udev->dev);
1680         /* Free the device number and delete the parent's children[]
1681          * (or root_hub) pointer.
1682          */
1683         release_devnum(udev);
1685         /* Avoid races with recursively_mark_NOTATTACHED() */
1686         spin_lock_irq(&device_state_lock);
1687         *pdev = NULL;
1688         spin_unlock_irq(&device_state_lock);
1690         hub_free_dev(udev);
1692         put_device(&udev->dev);
1695 #ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
1696 static void show_string(struct usb_device *udev, char *id, char *string)
1698         if (!string)
1699                 return;
1700         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1703 static void announce_device(struct usb_device *udev)
1705         dev_info(&udev->dev, "New USB device found, idVendor=%04x, idProduct=%04x\n",
1706                 le16_to_cpu(udev->descriptor.idVendor),
1707                 le16_to_cpu(udev->descriptor.idProduct));
1708         dev_info(&udev->dev,
1709                 "New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
1710                 udev->descriptor.iManufacturer,
1711                 udev->descriptor.iProduct,
1712                 udev->descriptor.iSerialNumber);
1713         show_string(udev, "Product", udev->product);
1714         show_string(udev, "Manufacturer", udev->manufacturer);
1715         show_string(udev, "SerialNumber", udev->serial);
1717 #else
1718 static inline void announce_device(struct usb_device *udev) { }
1719 #endif
1721 #ifdef  CONFIG_USB_OTG
1722 #include "otg_whitelist.h"
1723 #endif
1725 /**
1726  * usb_enumerate_device_otg - FIXME (usbcore-internal)
1727  * @udev: newly addressed device (in ADDRESS state)
1728  *
1729  * Finish enumeration for On-The-Go devices
1730  */
1731 static int usb_enumerate_device_otg(struct usb_device *udev)
1733         int err = 0;
1735 #ifdef  CONFIG_USB_OTG
1736         /*
1737          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1738          * to wake us after we've powered off VBUS; and HNP, switching roles
1739          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1740          */
1741         if (!udev->bus->is_b_host
1742                         && udev->config
1743                         && udev->parent == udev->bus->root_hub) {
1744                 struct usb_otg_descriptor       *desc = NULL;
1745                 struct usb_bus                  *bus = udev->bus;
1747                 /* descriptor may appear anywhere in config */
1748                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1749                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1750                                         USB_DT_OTG, (void **) &desc) == 0) {
1751                         if (desc->bmAttributes & USB_OTG_HNP) {
1752                                 unsigned                port1 = udev->portnum;
1754                                 dev_info(&udev->dev,
1755                                         "Dual-Role OTG device on %sHNP port\n",
1756                                         (port1 == bus->otg_port)
1757                                                 ? "" : "non-");
1759                                 /* enable HNP before suspend, it's simpler */
1760                                 if (port1 == bus->otg_port)
1761                                         bus->b_hnp_enable = 1;
1762                                 err = usb_control_msg(udev,
1763                                         usb_sndctrlpipe(udev, 0),
1764                                         USB_REQ_SET_FEATURE, 0,
1765                                         bus->b_hnp_enable
1766                                                 ? USB_DEVICE_B_HNP_ENABLE
1767                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1768                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1769                                 if (err < 0) {
1770                                         /* OTG MESSAGE: report errors here,
1771                                          * customize to match your product.
1772                                          */
1773                                         dev_info(&udev->dev,
1774                                                 "can't set HNP mode: %d\n",
1775                                                 err);
1776                                         bus->b_hnp_enable = 0;
1777                                 }
1778                         }
1779                 }
1780         }
1782         if (!is_targeted(udev)) {
1784                 /* Maybe it can talk to us, though we can't talk to it.
1785                  * (Includes HNP test device.)
1786                  */
1787                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1788                         err = usb_port_suspend(udev, PMSG_SUSPEND);
1789                         if (err < 0)
1790                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1791                 }
1792                 err = -ENOTSUPP;
1793                 goto fail;
1794         }
1795 fail:
1796 #endif
1797         return err;
1801 /**
1802  * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
1803  * @udev: newly addressed device (in ADDRESS state)
1804  *
1805  * This is only called by usb_new_device() and usb_authorize_device()
1806  * and FIXME -- all comments that apply to them apply here wrt to
1807  * environment.
1808  *
1809  * If the device is WUSB and not authorized, we don't attempt to read
1810  * the string descriptors, as they will be errored out by the device
1811  * until it has been authorized.
1812  */
1813 static int usb_enumerate_device(struct usb_device *udev)
1815         int err;
1817         if (udev->config == NULL) {
1818                 err = usb_get_configuration(udev);
1819                 if (err < 0) {
1820                         dev_err(&udev->dev, "can't read configurations, error %d\n",
1821                                 err);
1822                         goto fail;
1823                 }
1824         }
1825         if (udev->wusb == 1 && udev->authorized == 0) {
1826                 udev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1827                 udev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1828                 udev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1829         }
1830         else {
1831                 /* read the standard strings and cache them if present */
1832                 udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1833                 udev->manufacturer = usb_cache_string(udev,
1834                                                       udev->descriptor.iManufacturer);
1835                 udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1836         }
1837         err = usb_enumerate_device_otg(udev);
1838 fail:
1839         return err;
1843 /**
1844  * usb_new_device - perform initial device setup (usbcore-internal)
1845  * @udev: newly addressed device (in ADDRESS state)
1846  *
1847  * This is called with devices which have been detected but not fully
1848  * enumerated.  The device descriptor is available, but not descriptors
1849  * for any device configuration.  The caller must have locked either
1850  * the parent hub (if udev is a normal device) or else the
1851  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1852  * udev has already been installed, but udev is not yet visible through
1853  * sysfs or other filesystem code.
1854  *
1855  * It will return if the device is configured properly or not.  Zero if
1856  * the interface was registered with the driver core; else a negative
1857  * errno value.
1858  *
1859  * This call is synchronous, and may not be used in an interrupt context.
1860  *
1861  * Only the hub driver or root-hub registrar should ever call this.
1862  */
1863 int usb_new_device(struct usb_device *udev)
1865         int err;
1867         if (udev->parent) {
1868                 /* Initialize non-root-hub device wakeup to disabled;
1869                  * device (un)configuration controls wakeup capable
1870                  * sysfs power/wakeup controls wakeup enabled/disabled
1871                  */
1872                 device_init_wakeup(&udev->dev, 0);
1873         }
1875         /* Tell the runtime-PM framework the device is active */
1876         pm_runtime_set_active(&udev->dev);
1877         pm_runtime_get_noresume(&udev->dev);
1878         pm_runtime_use_autosuspend(&udev->dev);
1879         pm_runtime_enable(&udev->dev);
1881         /* By default, forbid autosuspend for all devices.  It will be
1882          * allowed for hubs during binding.
1883          */
1884         usb_disable_autosuspend(udev);
1886         err = usb_enumerate_device(udev);       /* Read descriptors */
1887         if (err < 0)
1888                 goto fail;
1889         dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
1890                         udev->devnum, udev->bus->busnum,
1891                         (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1892         /* export the usbdev device-node for libusb */
1893         udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
1894                         (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
1896         /* Tell the world! */
1897         announce_device(udev);
1899         device_enable_async_suspend(&udev->dev);
1900         /* Register the device.  The device driver is responsible
1901          * for configuring the device and invoking the add-device
1902          * notifier chain (used by usbfs and possibly others).
1903          */
1904         err = device_add(&udev->dev);
1905         if (err) {
1906                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1907                 goto fail;
1908         }
1910         (void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
1911         usb_mark_last_busy(udev);
1912         pm_runtime_put_sync_autosuspend(&udev->dev);
1913         return err;
1915 fail:
1916         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1917         pm_runtime_disable(&udev->dev);
1918         pm_runtime_set_suspended(&udev->dev);
1919         return err;
1923 /**
1924  * usb_deauthorize_device - deauthorize a device (usbcore-internal)
1925  * @usb_dev: USB device
1926  *
1927  * Move the USB device to a very basic state where interfaces are disabled
1928  * and the device is in fact unconfigured and unusable.
1929  *
1930  * We share a lock (that we have) with device_del(), so we need to
1931  * defer its call.
1932  */
1933 int usb_deauthorize_device(struct usb_device *usb_dev)
1935         usb_lock_device(usb_dev);
1936         if (usb_dev->authorized == 0)
1937                 goto out_unauthorized;
1939         usb_dev->authorized = 0;
1940         usb_set_configuration(usb_dev, -1);
1942         kfree(usb_dev->product);
1943         usb_dev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1944         kfree(usb_dev->manufacturer);
1945         usb_dev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1946         kfree(usb_dev->serial);
1947         usb_dev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
1949         usb_destroy_configuration(usb_dev);
1950         usb_dev->descriptor.bNumConfigurations = 0;
1952 out_unauthorized:
1953         usb_unlock_device(usb_dev);
1954         return 0;
1958 int usb_authorize_device(struct usb_device *usb_dev)
1960         int result = 0, c;
1962         usb_lock_device(usb_dev);
1963         if (usb_dev->authorized == 1)
1964                 goto out_authorized;
1966         result = usb_autoresume_device(usb_dev);
1967         if (result < 0) {
1968                 dev_err(&usb_dev->dev,
1969                         "can't autoresume for authorization: %d\n", result);
1970                 goto error_autoresume;
1971         }
1972         result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
1973         if (result < 0) {
1974                 dev_err(&usb_dev->dev, "can't re-read device descriptor for "
1975                         "authorization: %d\n", result);
1976                 goto error_device_descriptor;
1977         }
1979         kfree(usb_dev->product);
1980         usb_dev->product = NULL;
1981         kfree(usb_dev->manufacturer);
1982         usb_dev->manufacturer = NULL;
1983         kfree(usb_dev->serial);
1984         usb_dev->serial = NULL;
1986         usb_dev->authorized = 1;
1987         result = usb_enumerate_device(usb_dev);
1988         if (result < 0)
1989                 goto error_enumerate;
1990         /* Choose and set the configuration.  This registers the interfaces
1991          * with the driver core and lets interface drivers bind to them.
1992          */
1993         c = usb_choose_configuration(usb_dev);
1994         if (c >= 0) {
1995                 result = usb_set_configuration(usb_dev, c);
1996                 if (result) {
1997                         dev_err(&usb_dev->dev,
1998                                 "can't set config #%d, error %d\n", c, result);
1999                         /* This need not be fatal.  The user can try to
2000                          * set other configurations. */
2001                 }
2002         }
2003         dev_info(&usb_dev->dev, "authorized to connect\n");
2005 error_enumerate:
2006 error_device_descriptor:
2007         usb_autosuspend_device(usb_dev);
2008 error_autoresume:
2009 out_authorized:
2010         usb_unlock_device(usb_dev);     // complements locktree
2011         return result;
2015 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
2016 static unsigned hub_is_wusb(struct usb_hub *hub)
2018         struct usb_hcd *hcd;
2019         if (hub->hdev->parent != NULL)  /* not a root hub? */
2020                 return 0;
2021         hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
2022         return hcd->wireless;
2026 #define PORT_RESET_TRIES        5
2027 #define SET_ADDRESS_TRIES       2
2028 #define GET_DESCRIPTOR_TRIES    2
2029 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
2030 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
2032 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
2033 #define HUB_SHORT_RESET_TIME    10
2034 #define HUB_BH_RESET_TIME       50
2035 #define HUB_LONG_RESET_TIME     200
2036 #define HUB_RESET_TIMEOUT       500
2038 static int hub_port_reset(struct usb_hub *hub, int port1,
2039                         struct usb_device *udev, unsigned int delay, bool warm);
2041 /* Is a USB 3.0 port in the Inactive state? */
2042 static bool hub_port_inactive(struct usb_hub *hub, u16 portstatus)
2044         return hub_is_superspeed(hub->hdev) &&
2045                 (portstatus & USB_PORT_STAT_LINK_STATE) ==
2046                 USB_SS_PORT_LS_SS_INACTIVE;
2049 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
2050                         struct usb_device *udev, unsigned int delay, bool warm)
2052         int delay_time, ret;
2053         u16 portstatus;
2054         u16 portchange;
2056         for (delay_time = 0;
2057                         delay_time < HUB_RESET_TIMEOUT;
2058                         delay_time += delay) {
2059                 /* wait to give the device a chance to reset */
2060                 msleep(delay);
2062                 /* read and decode port status */
2063                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2064                 if (ret < 0)
2065                         return ret;
2067                 /*
2068                  * Some buggy devices require a warm reset to be issued even
2069                  * when the port appears not to be connected.
2070                  */
2071                 if (!warm) {
2072                         /*
2073                          * Some buggy devices can cause an NEC host controller
2074                          * to transition to the "Error" state after a hot port
2075                          * reset.  This will show up as the port state in
2076                          * "Inactive", and the port may also report a
2077                          * disconnect.  Forcing a warm port reset seems to make
2078                          * the device work.
2079                          *
2080                          * See https://bugzilla.kernel.org/show_bug.cgi?id=41752
2081                          */
2082                         if (hub_port_inactive(hub, portstatus)) {
2083                                 int ret;
2085                                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
2086                                         clear_port_feature(hub->hdev, port1,
2087                                                         USB_PORT_FEAT_C_CONNECTION);
2088                                 if (portchange & USB_PORT_STAT_C_LINK_STATE)
2089                                         clear_port_feature(hub->hdev, port1,
2090                                                         USB_PORT_FEAT_C_PORT_LINK_STATE);
2091                                 if (portchange & USB_PORT_STAT_C_RESET)
2092                                         clear_port_feature(hub->hdev, port1,
2093                                                         USB_PORT_FEAT_C_RESET);
2094                                 dev_dbg(hub->intfdev, "hot reset failed, warm reset port %d\n",
2095                                                 port1);
2096                                 ret = hub_port_reset(hub, port1,
2097                                                 udev, HUB_BH_RESET_TIME,
2098                                                 true);
2099                                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
2100                                         clear_port_feature(hub->hdev, port1,
2101                                                         USB_PORT_FEAT_C_CONNECTION);
2102                                 return ret;
2103                         }
2104                         /* Device went away? */
2105                         if (!(portstatus & USB_PORT_STAT_CONNECTION))
2106                                 return -ENOTCONN;
2108                         /* bomb out completely if the connection bounced */
2109                         if ((portchange & USB_PORT_STAT_C_CONNECTION))
2110                                 return -ENOTCONN;
2112                         /* if we`ve finished resetting, then break out of
2113                          * the loop
2114                          */
2115                         if (!(portstatus & USB_PORT_STAT_RESET) &&
2116                             (portstatus & USB_PORT_STAT_ENABLE)) {
2117                                 if (hub_is_wusb(hub))
2118                                         udev->speed = USB_SPEED_WIRELESS;
2119                                 else if (hub_is_superspeed(hub->hdev))
2120                                         udev->speed = USB_SPEED_SUPER;
2121                                 else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
2122                                         udev->speed = USB_SPEED_HIGH;
2123                                 else if (portstatus & USB_PORT_STAT_LOW_SPEED)
2124                                         udev->speed = USB_SPEED_LOW;
2125                                 else
2126                                         udev->speed = USB_SPEED_FULL;
2127                                 return 0;
2128                         }
2129                 } else {
2130                         if (portchange & USB_PORT_STAT_C_BH_RESET)
2131                                 return 0;
2132                 }
2134                 /* switch to the long delay after two short delay failures */
2135                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
2136                         delay = HUB_LONG_RESET_TIME;
2138                 dev_dbg (hub->intfdev,
2139                         "port %d not %sreset yet, waiting %dms\n",
2140                         port1, warm ? "warm " : "", delay);
2141         }
2143         return -EBUSY;
2146 static void hub_port_finish_reset(struct usb_hub *hub, int port1,
2147                         struct usb_device *udev, int *status, bool warm)
2149         switch (*status) {
2150         case 0:
2151                 if (!warm) {
2152                         struct usb_hcd *hcd;
2153                         /* TRSTRCY = 10 ms; plus some extra */
2154                         msleep(10 + 40);
2155                         update_devnum(udev, 0);
2156                         hcd = bus_to_hcd(udev->bus);
2157                         if (hcd->driver->reset_device) {
2158                                 *status = hcd->driver->reset_device(hcd, udev);
2159                                 if (*status < 0) {
2160                                         dev_err(&udev->dev, "Cannot reset "
2161                                                         "HCD device state\n");
2162                                         break;
2163                                 }
2164                         }
2165                 }
2166                 /* FALL THROUGH */
2167         case -ENOTCONN:
2168         case -ENODEV:
2169                 clear_port_feature(hub->hdev,
2170                                 port1, USB_PORT_FEAT_C_RESET);
2171                 /* FIXME need disconnect() for NOTATTACHED device */
2172                 if (warm) {
2173                         clear_port_feature(hub->hdev, port1,
2174                                         USB_PORT_FEAT_C_BH_PORT_RESET);
2175                         clear_port_feature(hub->hdev, port1,
2176                                         USB_PORT_FEAT_C_PORT_LINK_STATE);
2177                 } else {
2178                         usb_set_device_state(udev, *status
2179                                         ? USB_STATE_NOTATTACHED
2180                                         : USB_STATE_DEFAULT);
2181                 }
2182                 break;
2183         }
2186 /* Handle port reset and port warm(BH) reset (for USB3 protocol ports) */
2187 static int hub_port_reset(struct usb_hub *hub, int port1,
2188                         struct usb_device *udev, unsigned int delay, bool warm)
2190         int i, status;
2192         if (!warm) {
2193                 /* Block EHCI CF initialization during the port reset.
2194                  * Some companion controllers don't like it when they mix.
2195                  */
2196                 down_read(&ehci_cf_port_reset_rwsem);
2197         } else {
2198                 if (!hub_is_superspeed(hub->hdev)) {
2199                         dev_err(hub->intfdev, "only USB3 hub support "
2200                                                 "warm reset\n");
2201                         return -EINVAL;
2202                 }
2203         }
2205         /* Reset the port */
2206         for (i = 0; i < PORT_RESET_TRIES; i++) {
2207                 status = set_port_feature(hub->hdev, port1, (warm ?
2208                                         USB_PORT_FEAT_BH_PORT_RESET :
2209                                         USB_PORT_FEAT_RESET));
2210                 if (status) {
2211                         dev_err(hub->intfdev,
2212                                         "cannot %sreset port %d (err = %d)\n",
2213                                         warm ? "warm " : "", port1, status);
2214                 } else {
2215                         status = hub_port_wait_reset(hub, port1, udev, delay,
2216                                                                 warm);
2217                         if (status && status != -ENOTCONN)
2218                                 dev_dbg(hub->intfdev,
2219                                                 "port_wait_reset: err = %d\n",
2220                                                 status);
2221                 }
2223                 /* return on disconnect or reset */
2224                 if (status == 0 || status == -ENOTCONN || status == -ENODEV) {
2225                         hub_port_finish_reset(hub, port1, udev, &status, warm);
2226                         goto done;
2227                 }
2229                 dev_dbg (hub->intfdev,
2230                         "port %d not enabled, trying %sreset again...\n",
2231                         port1, warm ? "warm " : "");
2232                 delay = HUB_LONG_RESET_TIME;
2233         }
2235         dev_err (hub->intfdev,
2236                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
2237                 port1);
2239 done:
2240         if (!warm)
2241                 up_read(&ehci_cf_port_reset_rwsem);
2243         return status;
2246 /* Check if a port is power on */
2247 static int port_is_power_on(struct usb_hub *hub, unsigned portstatus)
2249         int ret = 0;
2251         if (hub_is_superspeed(hub->hdev)) {
2252                 if (portstatus & USB_SS_PORT_STAT_POWER)
2253                         ret = 1;
2254         } else {
2255                 if (portstatus & USB_PORT_STAT_POWER)
2256                         ret = 1;
2257         }
2259         return ret;
2262 #ifdef  CONFIG_PM
2264 /* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */
2265 static int port_is_suspended(struct usb_hub *hub, unsigned portstatus)
2267         int ret = 0;
2269         if (hub_is_superspeed(hub->hdev)) {
2270                 if ((portstatus & USB_PORT_STAT_LINK_STATE)
2271                                 == USB_SS_PORT_LS_U3)
2272                         ret = 1;
2273         } else {
2274                 if (portstatus & USB_PORT_STAT_SUSPEND)
2275                         ret = 1;
2276         }
2278         return ret;
2281 /* Determine whether the device on a port is ready for a normal resume,
2282  * is ready for a reset-resume, or should be disconnected.
2283  */
2284 static int check_port_resume_type(struct usb_device *udev,
2285                 struct usb_hub *hub, int port1,
2286                 int status, unsigned portchange, unsigned portstatus)
2288         /* Is the device still present? */
2289         if (status || port_is_suspended(hub, portstatus) ||
2290                         !port_is_power_on(hub, portstatus) ||
2291                         !(portstatus & USB_PORT_STAT_CONNECTION)) {
2292                 if (status >= 0)
2293                         status = -ENODEV;
2294         }
2296         /* Can't do a normal resume if the port isn't enabled,
2297          * so try a reset-resume instead.
2298          */
2299         else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
2300                 if (udev->persist_enabled)
2301                         udev->reset_resume = 1;
2302                 else
2303                         status = -ENODEV;
2304         }
2306         if (status) {
2307                 dev_dbg(hub->intfdev,
2308                                 "port %d status %04x.%04x after resume, %d\n",
2309                                 port1, portchange, portstatus, status);
2310         } else if (udev->reset_resume) {
2312                 /* Late port handoff can set status-change bits */
2313                 if (portchange & USB_PORT_STAT_C_CONNECTION)
2314                         clear_port_feature(hub->hdev, port1,
2315                                         USB_PORT_FEAT_C_CONNECTION);
2316                 if (portchange & USB_PORT_STAT_C_ENABLE)
2317                         clear_port_feature(hub->hdev, port1,
2318                                         USB_PORT_FEAT_C_ENABLE);
2319         }
2321         return status;
2324 #ifdef  CONFIG_USB_SUSPEND
2326 /*
2327  * usb_port_suspend - suspend a usb device's upstream port
2328  * @udev: device that's no longer in active use, not a root hub
2329  * Context: must be able to sleep; device not locked; pm locks held
2330  *
2331  * Suspends a USB device that isn't in active use, conserving power.
2332  * Devices may wake out of a suspend, if anything important happens,
2333  * using the remote wakeup mechanism.  They may also be taken out of
2334  * suspend by the host, using usb_port_resume().  It's also routine
2335  * to disconnect devices while they are suspended.
2336  *
2337  * This only affects the USB hardware for a device; its interfaces
2338  * (and, for hubs, child devices) must already have been suspended.
2339  *
2340  * Selective port suspend reduces power; most suspended devices draw
2341  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
2342  * All devices below the suspended port are also suspended.
2343  *
2344  * Devices leave suspend state when the host wakes them up.  Some devices
2345  * also support "remote wakeup", where the device can activate the USB
2346  * tree above them to deliver data, such as a keypress or packet.  In
2347  * some cases, this wakes the USB host.
2348  *
2349  * Suspending OTG devices may trigger HNP, if that's been enabled
2350  * between a pair of dual-role devices.  That will change roles, such
2351  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
2352  *
2353  * Devices on USB hub ports have only one "suspend" state, corresponding
2354  * to ACPI D2, "may cause the device to lose some context".
2355  * State transitions include:
2356  *
2357  *   - suspend, resume ... when the VBUS power link stays live
2358  *   - suspend, disconnect ... VBUS lost
2359  *
2360  * Once VBUS drop breaks the circuit, the port it's using has to go through
2361  * normal re-enumeration procedures, starting with enabling VBUS power.
2362  * Other than re-initializing the hub (plug/unplug, except for root hubs),
2363  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
2364  * timer, no SRP, no requests through sysfs.
2365  *
2366  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
2367  * the root hub for their bus goes into global suspend ... so we don't
2368  * (falsely) update the device power state to say it suspended.
2369  *
2370  * Returns 0 on success, else negative errno.
2371  */
2372 int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2374         struct usb_hub  *hub = hdev_to_hub(udev->parent);
2375         int             port1 = udev->portnum;
2376         int             status;
2378         /* enable remote wakeup when appropriate; this lets the device
2379          * wake up the upstream hub (including maybe the root hub).
2380          *
2381          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
2382          * we don't explicitly enable it here.
2383          */
2384         if (udev->do_remote_wakeup) {
2385                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2386                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
2387                                 USB_DEVICE_REMOTE_WAKEUP, 0,
2388                                 NULL, 0,
2389                                 USB_CTRL_SET_TIMEOUT);
2390                 if (status) {
2391                         dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
2392                                         status);
2393                         /* bail if autosuspend is requested */
2394                         if (PMSG_IS_AUTO(msg))
2395                                 return status;
2396                 }
2397         }
2399         /* disable USB2 hardware LPM */
2400         if (udev->usb2_hw_lpm_enabled == 1)
2401                 usb_set_usb2_hardware_lpm(udev, 0);
2403         /* see 7.1.7.6 */
2404         if (hub_is_superspeed(hub->hdev))
2405                 status = set_port_feature(hub->hdev,
2406                                 port1 | (USB_SS_PORT_LS_U3 << 3),
2407                                 USB_PORT_FEAT_LINK_STATE);
2408         else
2409                 status = set_port_feature(hub->hdev, port1,
2410                                                 USB_PORT_FEAT_SUSPEND);
2411         if (status) {
2412                 dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",
2413                                 port1, status);
2414                 /* paranoia:  "should not happen" */
2415                 if (udev->do_remote_wakeup)
2416                         (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
2417                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
2418                                 USB_DEVICE_REMOTE_WAKEUP, 0,
2419                                 NULL, 0,
2420                                 USB_CTRL_SET_TIMEOUT);
2422                 /* System sleep transitions should never fail */
2423                 if (!PMSG_IS_AUTO(msg))
2424                         status = 0;
2425         } else {
2426                 /* device has up to 10 msec to fully suspend */
2427                 dev_dbg(&udev->dev, "usb %ssuspend, wakeup %d\n",
2428                                 (PMSG_IS_AUTO(msg) ? "auto-" : ""),
2429                                 udev->do_remote_wakeup);
2430                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
2431                 msleep(10);
2432         }
2433         usb_mark_last_busy(hub->hdev);
2434         return status;
2437 /*
2438  * If the USB "suspend" state is in use (rather than "global suspend"),
2439  * many devices will be individually taken out of suspend state using
2440  * special "resume" signaling.  This routine kicks in shortly after
2441  * hardware resume signaling is finished, either because of selective
2442  * resume (by host) or remote wakeup (by device) ... now see what changed
2443  * in the tree that's rooted at this device.
2444  *
2445  * If @udev->reset_resume is set then the device is reset before the
2446  * status check is done.
2447  */
2448 static int finish_port_resume(struct usb_device *udev)
2450         int     status = 0;
2451         u16     devstatus;
2453         /* caller owns the udev device lock */
2454         dev_dbg(&udev->dev, "%s\n",
2455                 udev->reset_resume ? "finish reset-resume" : "finish resume");
2457         /* usb ch9 identifies four variants of SUSPENDED, based on what
2458          * state the device resumes to.  Linux currently won't see the
2459          * first two on the host side; they'd be inside hub_port_init()
2460          * during many timeouts, but khubd can't suspend until later.
2461          */
2462         usb_set_device_state(udev, udev->actconfig
2463                         ? USB_STATE_CONFIGURED
2464                         : USB_STATE_ADDRESS);
2466         /* 10.5.4.5 says not to reset a suspended port if the attached
2467          * device is enabled for remote wakeup.  Hence the reset
2468          * operation is carried out here, after the port has been
2469          * resumed.
2470          */
2471         if (udev->reset_resume)
2472  retry_reset_resume:
2473                 status = usb_reset_and_verify_device(udev);
2475         /* 10.5.4.5 says be sure devices in the tree are still there.
2476          * For now let's assume the device didn't go crazy on resume,
2477          * and device drivers will know about any resume quirks.
2478          */
2479         if (status == 0) {
2480                 devstatus = 0;
2481                 status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
2482                 if (status >= 0)
2483                         status = (status > 0 ? 0 : -ENODEV);
2485                 /* If a normal resume failed, try doing a reset-resume */
2486                 if (status && !udev->reset_resume && udev->persist_enabled) {
2487                         dev_dbg(&udev->dev, "retry with reset-resume\n");
2488                         udev->reset_resume = 1;
2489                         goto retry_reset_resume;
2490                 }
2491         }
2493         if (status) {
2494                 dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
2495                                 status);
2496         } else if (udev->actconfig) {
2497                 le16_to_cpus(&devstatus);
2498                 if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
2499                         status = usb_control_msg(udev,
2500                                         usb_sndctrlpipe(udev, 0),
2501                                         USB_REQ_CLEAR_FEATURE,
2502                                                 USB_RECIP_DEVICE,
2503                                         USB_DEVICE_REMOTE_WAKEUP, 0,
2504                                         NULL, 0,
2505                                         USB_CTRL_SET_TIMEOUT);
2506                         if (status)
2507                                 dev_dbg(&udev->dev,
2508                                         "disable remote wakeup, status %d\n",
2509                                         status);
2510                 }
2511                 status = 0;
2512         }
2513         return status;
2516 /*
2517  * usb_port_resume - re-activate a suspended usb device's upstream port
2518  * @udev: device to re-activate, not a root hub
2519  * Context: must be able to sleep; device not locked; pm locks held
2520  *
2521  * This will re-activate the suspended device, increasing power usage
2522  * while letting drivers communicate again with its endpoints.
2523  * USB resume explicitly guarantees that the power session between
2524  * the host and the device is the same as it was when the device
2525  * suspended.
2526  *
2527  * If @udev->reset_resume is set then this routine won't check that the
2528  * port is still enabled.  Furthermore, finish_port_resume() above will
2529  * reset @udev.  The end result is that a broken power session can be
2530  * recovered and @udev will appear to persist across a loss of VBUS power.
2531  *
2532  * For example, if a host controller doesn't maintain VBUS suspend current
2533  * during a system sleep or is reset when the system wakes up, all the USB
2534  * power sessions below it will be broken.  This is especially troublesome
2535  * for mass-storage devices containing mounted filesystems, since the
2536  * device will appear to have disconnected and all the memory mappings
2537  * to it will be lost.  Using the USB_PERSIST facility, the device can be
2538  * made to appear as if it had not disconnected.
2539  *
2540  * This facility can be dangerous.  Although usb_reset_and_verify_device() makes
2541  * every effort to insure that the same device is present after the
2542  * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
2543  * quite possible for a device to remain unaltered but its media to be
2544  * changed.  If the user replaces a flash memory card while the system is
2545  * asleep, he will have only himself to blame when the filesystem on the
2546  * new card is corrupted and the system crashes.
2547  *
2548  * Returns 0 on success, else negative errno.
2549  */
2550 int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2552         struct usb_hub  *hub = hdev_to_hub(udev->parent);
2553         int             port1 = udev->portnum;
2554         int             status;
2555         u16             portchange, portstatus;
2557         /* Skip the initial Clear-Suspend step for a remote wakeup */
2558         status = hub_port_status(hub, port1, &portstatus, &portchange);
2559         if (status == 0 && !port_is_suspended(hub, portstatus))
2560                 goto SuspendCleared;
2562         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
2564         set_bit(port1, hub->busy_bits);
2566         /* see 7.1.7.7; affects power usage, but not budgeting */
2567         if (hub_is_superspeed(hub->hdev))
2568                 status = set_port_feature(hub->hdev,
2569                                 port1 | (USB_SS_PORT_LS_U0 << 3),
2570                                 USB_PORT_FEAT_LINK_STATE);
2571         else
2572                 status = clear_port_feature(hub->hdev,
2573                                 port1, USB_PORT_FEAT_SUSPEND);
2574         if (status) {
2575                 dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
2576                                 port1, status);
2577         } else {
2578                 /* drive resume for at least 20 msec */
2579                 dev_dbg(&udev->dev, "usb %sresume\n",
2580                                 (PMSG_IS_AUTO(msg) ? "auto-" : ""));
2581                 msleep(25);
2583                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
2584                  * stop resume signaling.  Then finish the resume
2585                  * sequence.
2586                  */
2587                 status = hub_port_status(hub, port1, &portstatus, &portchange);
2589                 /* TRSMRCY = 10 msec */
2590                 msleep(10);
2591         }
2593  SuspendCleared:
2594         if (status == 0) {
2595                 if (hub_is_superspeed(hub->hdev)) {
2596                         if (portchange & USB_PORT_STAT_C_LINK_STATE)
2597                                 clear_port_feature(hub->hdev, port1,
2598                                         USB_PORT_FEAT_C_PORT_LINK_STATE);
2599                 } else {
2600                         if (portchange & USB_PORT_STAT_C_SUSPEND)
2601                                 clear_port_feature(hub->hdev, port1,
2602                                                 USB_PORT_FEAT_C_SUSPEND);
2603                 }
2604         }
2606         clear_bit(port1, hub->busy_bits);
2608         status = check_port_resume_type(udev,
2609                         hub, port1, status, portchange, portstatus);
2610         if (status == 0)
2611                 status = finish_port_resume(udev);
2612         if (status < 0) {
2613                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2614                 hub_port_logical_disconnect(hub, port1);
2615         } else  {
2616                 /* Try to enable USB2 hardware LPM */
2617                 if (udev->usb2_hw_lpm_capable == 1)
2618                         usb_set_usb2_hardware_lpm(udev, 1);
2619         }
2621         return status;
2624 /* caller has locked udev */
2625 int usb_remote_wakeup(struct usb_device *udev)
2627         int     status = 0;
2629         if (udev->state == USB_STATE_SUSPENDED) {
2630                 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
2631                 status = usb_autoresume_device(udev);
2632                 if (status == 0) {
2633                         /* Let the drivers do their thing, then... */
2634                         usb_autosuspend_device(udev);
2635                 }
2636         }
2637         return status;
2640 #else   /* CONFIG_USB_SUSPEND */
2642 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
2644 int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
2646         return 0;
2649 /* However we may need to do a reset-resume */
2651 int usb_port_resume(struct usb_device *udev, pm_message_t msg)
2653         struct usb_hub  *hub = hdev_to_hub(udev->parent);
2654         int             port1 = udev->portnum;
2655         int             status;
2656         u16             portchange, portstatus;
2658         status = hub_port_status(hub, port1, &portstatus, &portchange);
2659         status = check_port_resume_type(udev,
2660                         hub, port1, status, portchange, portstatus);
2662         if (status) {
2663                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
2664                 hub_port_logical_disconnect(hub, port1);
2665         } else if (udev->reset_resume) {
2666                 dev_dbg(&udev->dev, "reset-resume\n");
2667                 status = usb_reset_and_verify_device(udev);
2668         }
2669         return status;
2672 #endif
2674 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
2676         struct usb_hub          *hub = usb_get_intfdata (intf);
2677         struct usb_device       *hdev = hub->hdev;
2678         unsigned                port1;
2680         /* Warn if children aren't already suspended */
2681         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
2682                 struct usb_device       *udev;
2684                 udev = hdev->children [port1-1];
2685                 if (udev && udev->can_submit) {
2686                         dev_warn(&intf->dev, "port %d nyet suspended\n", port1);
2687                         if (PMSG_IS_AUTO(msg))
2688                                 return -EBUSY;
2689                 }
2690         }
2692         dev_dbg(&intf->dev, "%s\n", __func__);
2694         /* stop khubd and related activity */
2695         hub_quiesce(hub, HUB_SUSPEND);
2696         return 0;
2699 static int hub_resume(struct usb_interface *intf)
2701         struct usb_hub *hub = usb_get_intfdata(intf);
2703         dev_dbg(&intf->dev, "%s\n", __func__);
2704         hub_activate(hub, HUB_RESUME);
2705         return 0;
2708 static int hub_reset_resume(struct usb_interface *intf)
2710         struct usb_hub *hub = usb_get_intfdata(intf);
2712         dev_dbg(&intf->dev, "%s\n", __func__);
2713         hub_activate(hub, HUB_RESET_RESUME);
2714         return 0;
2717 /**
2718  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
2719  * @rhdev: struct usb_device for the root hub
2720  *
2721  * The USB host controller driver calls this function when its root hub
2722  * is resumed and Vbus power has been interrupted or the controller
2723  * has been reset.  The routine marks @rhdev as having lost power.
2724  * When the hub driver is resumed it will take notice and carry out
2725  * power-session recovery for all the "USB-PERSIST"-enabled child devices;
2726  * the others will be disconnected.
2727  */
2728 void usb_root_hub_lost_power(struct usb_device *rhdev)
2730         dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
2731         rhdev->reset_resume = 1;
2733 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
2735 #else   /* CONFIG_PM */
2737 #define hub_suspend             NULL
2738 #define hub_resume              NULL
2739 #define hub_reset_resume        NULL
2740 #endif
2743 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2744  *
2745  * Between connect detection and reset signaling there must be a delay
2746  * of 100ms at least for debounce and power-settling.  The corresponding
2747  * timer shall restart whenever the downstream port detects a disconnect.
2748  * 
2749  * Apparently there are some bluetooth and irda-dongles and a number of
2750  * low-speed devices for which this debounce period may last over a second.
2751  * Not covered by the spec - but easy to deal with.
2752  *
2753  * This implementation uses a 1500ms total debounce timeout; if the
2754  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2755  * every 25ms for transient disconnects.  When the port status has been
2756  * unchanged for 100ms it returns the port status.
2757  */
2758 static int hub_port_debounce(struct usb_hub *hub, int port1)
2760         int ret;
2761         int total_time, stable_time = 0;
2762         u16 portchange, portstatus;
2763         unsigned connection = 0xffff;
2765         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2766                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2767                 if (ret < 0)
2768                         return ret;
2770                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2771                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2772                         stable_time += HUB_DEBOUNCE_STEP;
2773                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2774                                 break;
2775                 } else {
2776                         stable_time = 0;
2777                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2778                 }
2780                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2781                         clear_port_feature(hub->hdev, port1,
2782                                         USB_PORT_FEAT_C_CONNECTION);
2783                 }
2785                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2786                         break;
2787                 msleep(HUB_DEBOUNCE_STEP);
2788         }
2790         dev_dbg (hub->intfdev,
2791                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2792                 port1, total_time, stable_time, portstatus);
2794         if (stable_time < HUB_DEBOUNCE_STABLE)
2795                 return -ETIMEDOUT;
2796         return portstatus;
2799 void usb_ep0_reinit(struct usb_device *udev)
2801         usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
2802         usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
2803         usb_enable_endpoint(udev, &udev->ep0, true);
2805 EXPORT_SYMBOL_GPL(usb_ep0_reinit);
2807 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2808 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2810 static int hub_set_address(struct usb_device *udev, int devnum)
2812         int retval;
2813         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2815         /*
2816          * The host controller will choose the device address,
2817          * instead of the core having chosen it earlier
2818          */
2819         if (!hcd->driver->address_device && devnum <= 1)
2820                 return -EINVAL;
2821         if (udev->state == USB_STATE_ADDRESS)
2822                 return 0;
2823         if (udev->state != USB_STATE_DEFAULT)
2824                 return -EINVAL;
2825         if (hcd->driver->address_device)
2826                 retval = hcd->driver->address_device(hcd, udev);
2827         else
2828                 retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2829                                 USB_REQ_SET_ADDRESS, 0, devnum, 0,
2830                                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2831         if (retval == 0) {
2832                 update_devnum(udev, devnum);
2833                 /* Device now using proper address. */
2834                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2835                 usb_ep0_reinit(udev);
2836         }
2837         return retval;
2840 /* Reset device, (re)assign address, get device descriptor.
2841  * Device connection must be stable, no more debouncing needed.
2842  * Returns device in USB_STATE_ADDRESS, except on error.
2843  *
2844  * If this is called for an already-existing device (as part of
2845  * usb_reset_and_verify_device), the caller must own the device lock.  For a
2846  * newly detected device that is not accessible through any global
2847  * pointers, it's not necessary to lock the device.
2848  */
2849 static int
2850 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2851                 int retry_counter)
2853         static DEFINE_MUTEX(usb_address0_mutex);
2855         struct usb_device       *hdev = hub->hdev;
2856         struct usb_hcd          *hcd = bus_to_hcd(hdev->bus);
2857         int                     i, j, retval;
2858         unsigned                delay = HUB_SHORT_RESET_TIME;
2859         enum usb_device_speed   oldspeed = udev->speed;
2860         const char              *speed;
2861         int                     devnum = udev->devnum;
2863         /* root hub ports have a slightly longer reset period
2864          * (from USB 2.0 spec, section 7.1.7.5)
2865          */
2866         if (!hdev->parent) {
2867                 delay = HUB_ROOT_RESET_TIME;
2868                 if (port1 == hdev->bus->otg_port)
2869                         hdev->bus->b_hnp_enable = 0;
2870         }
2872         /* Some low speed devices have problems with the quick delay, so */
2873         /*  be a bit pessimistic with those devices. RHbug #23670 */
2874         if (oldspeed == USB_SPEED_LOW)
2875                 delay = HUB_LONG_RESET_TIME;
2877         mutex_lock(&usb_address0_mutex);
2879         /* Reset the device; full speed may morph to high speed */
2880         /* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
2881         retval = hub_port_reset(hub, port1, udev, delay, false);
2882         if (retval < 0)         /* error or disconnect */
2883                 goto fail;
2884         /* success, speed is known */
2886         retval = -ENODEV;
2888         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2889                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2890                 goto fail;
2891         }
2892         oldspeed = udev->speed;
2894         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2895          * it's fixed size except for full speed devices.
2896          * For Wireless USB devices, ep0 max packet is always 512 (tho
2897          * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
2898          */
2899         switch (udev->speed) {
2900         case USB_SPEED_SUPER:
2901         case USB_SPEED_WIRELESS:        /* fixed at 512 */
2902                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
2903                 break;
2904         case USB_SPEED_HIGH:            /* fixed at 64 */
2905                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
2906                 break;
2907         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2908                 /* to determine the ep0 maxpacket size, try to read
2909                  * the device descriptor to get bMaxPacketSize0 and
2910                  * then correct our initial guess.
2911                  */
2912                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
2913                 break;
2914         case USB_SPEED_LOW:             /* fixed at 8 */
2915                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
2916                 break;
2917         default:
2918                 goto fail;
2919         }
2921         if (udev->speed == USB_SPEED_WIRELESS)
2922                 speed = "variable speed Wireless";
2923         else
2924                 speed = usb_speed_string(udev->speed);
2926         if (udev->speed != USB_SPEED_SUPER)
2927                 dev_info(&udev->dev,
2928                                 "%s %s USB device number %d using %s\n",
2929                                 (udev->config) ? "reset" : "new", speed,
2930                                 devnum, udev->bus->controller->driver->name);
2932         /* Set up TT records, if needed  */
2933         if (hdev->tt) {
2934                 udev->tt = hdev->tt;
2935                 udev->ttport = hdev->ttport;
2936         } else if (udev->speed != USB_SPEED_HIGH
2937                         && hdev->speed == USB_SPEED_HIGH) {
2938                 if (!hub->tt.hub) {
2939                         dev_err(&udev->dev, "parent hub has no TT\n");
2940                         retval = -EINVAL;
2941                         goto fail;
2942                 }
2943                 udev->tt = &hub->tt;
2944                 udev->ttport = port1;
2945         }
2946  
2947         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2948          * Because device hardware and firmware is sometimes buggy in
2949          * this area, and this is how Linux has done it for ages.
2950          * Change it cautiously.
2951          *
2952          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2953          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2954          * so it may help with some non-standards-compliant devices.
2955          * Otherwise we start with SET_ADDRESS and then try to read the
2956          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2957          * value.
2958          */
2959         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2960                 if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3)) {
2961                         struct usb_device_descriptor *buf;
2962                         int r = 0;
2964 #define GET_DESCRIPTOR_BUFSIZE  64
2965                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2966                         if (!buf) {
2967                                 retval = -ENOMEM;
2968                                 continue;
2969                         }
2971                         /* Retry on all errors; some devices are flakey.
2972                          * 255 is for WUSB devices, we actually need to use
2973                          * 512 (WUSB1.0[4.8.1]).
2974                          */
2975                         for (j = 0; j < 3; ++j) {
2976                                 buf->bMaxPacketSize0 = 0;
2977                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2978                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2979                                         USB_DT_DEVICE << 8, 0,
2980                                         buf, GET_DESCRIPTOR_BUFSIZE,
2981                                         initial_descriptor_timeout);
2982                                 switch (buf->bMaxPacketSize0) {
2983                                 case 8: case 16: case 32: case 64: case 255:
2984                                         if (buf->bDescriptorType ==
2985                                                         USB_DT_DEVICE) {
2986                                                 r = 0;
2987                                                 break;
2988                                         }
2989                                         /* FALL THROUGH */
2990                                 default:
2991                                         if (r == 0)
2992                                                 r = -EPROTO;
2993                                         break;
2994                                 }
2995                                 if (r == 0)
2996                                         break;
2997                         }