xref: /linux/drivers/usb/core/hcd.c (revision 5fd54ace4721fc5ce2bb5aef6318fcf17f421460)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright Linus Torvalds 1999
4  * (C) Copyright Johannes Erdfelt 1999-2001
5  * (C) Copyright Andreas Gal 1999
6  * (C) Copyright Gregory P. Smith 1999
7  * (C) Copyright Deti Fliegl 1999
8  * (C) Copyright Randy Dunlap 2000
9  * (C) Copyright David Brownell 2000-2002
10  *
11  * This program is free software; you can redistribute it and/or modify it
12  * under the terms of the GNU General Public License as published by the
13  * Free Software Foundation; either version 2 of the License, or (at your
14  * option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful, but
17  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
18  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
19  * for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software Foundation,
23  * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24  */
25 
26 #include <linux/bcd.h>
27 #include <linux/module.h>
28 #include <linux/version.h>
29 #include <linux/kernel.h>
30 #include <linux/sched/task_stack.h>
31 #include <linux/slab.h>
32 #include <linux/completion.h>
33 #include <linux/utsname.h>
34 #include <linux/mm.h>
35 #include <asm/io.h>
36 #include <linux/device.h>
37 #include <linux/dma-mapping.h>
38 #include <linux/mutex.h>
39 #include <asm/irq.h>
40 #include <asm/byteorder.h>
41 #include <asm/unaligned.h>
42 #include <linux/platform_device.h>
43 #include <linux/workqueue.h>
44 #include <linux/pm_runtime.h>
45 #include <linux/types.h>
46 
47 #include <linux/phy/phy.h>
48 #include <linux/usb.h>
49 #include <linux/usb/hcd.h>
50 #include <linux/usb/phy.h>
51 #include <linux/usb/otg.h>
52 
53 #include "usb.h"
54 
55 
56 /*-------------------------------------------------------------------------*/
57 
58 /*
59  * USB Host Controller Driver framework
60  *
61  * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
62  * HCD-specific behaviors/bugs.
63  *
64  * This does error checks, tracks devices and urbs, and delegates to a
65  * "hc_driver" only for code (and data) that really needs to know about
66  * hardware differences.  That includes root hub registers, i/o queues,
67  * and so on ... but as little else as possible.
68  *
69  * Shared code includes most of the "root hub" code (these are emulated,
70  * though each HC's hardware works differently) and PCI glue, plus request
71  * tracking overhead.  The HCD code should only block on spinlocks or on
72  * hardware handshaking; blocking on software events (such as other kernel
73  * threads releasing resources, or completing actions) is all generic.
74  *
75  * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
76  * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
77  * only by the hub driver ... and that neither should be seen or used by
78  * usb client device drivers.
79  *
80  * Contributors of ideas or unattributed patches include: David Brownell,
81  * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
82  *
83  * HISTORY:
84  * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
85  *		associated cleanup.  "usb_hcd" still != "usb_bus".
86  * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
87  */
88 
89 /*-------------------------------------------------------------------------*/
90 
91 /* Keep track of which host controller drivers are loaded */
92 unsigned long usb_hcds_loaded;
93 EXPORT_SYMBOL_GPL(usb_hcds_loaded);
94 
95 /* host controllers we manage */
96 DEFINE_IDR (usb_bus_idr);
97 EXPORT_SYMBOL_GPL (usb_bus_idr);
98 
99 /* used when allocating bus numbers */
100 #define USB_MAXBUS		64
101 
102 /* used when updating list of hcds */
103 DEFINE_MUTEX(usb_bus_idr_lock);	/* exported only for usbfs */
104 EXPORT_SYMBOL_GPL (usb_bus_idr_lock);
105 
106 /* used for controlling access to virtual root hubs */
107 static DEFINE_SPINLOCK(hcd_root_hub_lock);
108 
109 /* used when updating an endpoint's URB list */
110 static DEFINE_SPINLOCK(hcd_urb_list_lock);
111 
112 /* used to protect against unlinking URBs after the device is gone */
113 static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
114 
115 /* wait queue for synchronous unlinks */
116 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
117 
118 static inline int is_root_hub(struct usb_device *udev)
119 {
120 	return (udev->parent == NULL);
121 }
122 
123 /*-------------------------------------------------------------------------*/
124 
125 /*
126  * Sharable chunks of root hub code.
127  */
128 
129 /*-------------------------------------------------------------------------*/
130 #define KERNEL_REL	bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff))
131 #define KERNEL_VER	bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff))
132 
133 /* usb 3.1 root hub device descriptor */
134 static const u8 usb31_rh_dev_descriptor[18] = {
135 	0x12,       /*  __u8  bLength; */
136 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
137 	0x10, 0x03, /*  __le16 bcdUSB; v3.1 */
138 
139 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
140 	0x00,	    /*  __u8  bDeviceSubClass; */
141 	0x03,       /*  __u8  bDeviceProtocol; USB 3 hub */
142 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
143 
144 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
145 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
146 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
147 
148 	0x03,       /*  __u8  iManufacturer; */
149 	0x02,       /*  __u8  iProduct; */
150 	0x01,       /*  __u8  iSerialNumber; */
151 	0x01        /*  __u8  bNumConfigurations; */
152 };
153 
154 /* usb 3.0 root hub device descriptor */
155 static const u8 usb3_rh_dev_descriptor[18] = {
156 	0x12,       /*  __u8  bLength; */
157 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
158 	0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
159 
160 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
161 	0x00,	    /*  __u8  bDeviceSubClass; */
162 	0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
163 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
164 
165 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
166 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
167 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
168 
169 	0x03,       /*  __u8  iManufacturer; */
170 	0x02,       /*  __u8  iProduct; */
171 	0x01,       /*  __u8  iSerialNumber; */
172 	0x01        /*  __u8  bNumConfigurations; */
173 };
174 
175 /* usb 2.5 (wireless USB 1.0) root hub device descriptor */
176 static const u8 usb25_rh_dev_descriptor[18] = {
177 	0x12,       /*  __u8  bLength; */
178 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
179 	0x50, 0x02, /*  __le16 bcdUSB; v2.5 */
180 
181 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
182 	0x00,	    /*  __u8  bDeviceSubClass; */
183 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
184 	0xFF,       /*  __u8  bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */
185 
186 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
187 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
188 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
189 
190 	0x03,       /*  __u8  iManufacturer; */
191 	0x02,       /*  __u8  iProduct; */
192 	0x01,       /*  __u8  iSerialNumber; */
193 	0x01        /*  __u8  bNumConfigurations; */
194 };
195 
196 /* usb 2.0 root hub device descriptor */
197 static const u8 usb2_rh_dev_descriptor[18] = {
198 	0x12,       /*  __u8  bLength; */
199 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
200 	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
201 
202 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
203 	0x00,	    /*  __u8  bDeviceSubClass; */
204 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
205 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
206 
207 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
208 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
209 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
210 
211 	0x03,       /*  __u8  iManufacturer; */
212 	0x02,       /*  __u8  iProduct; */
213 	0x01,       /*  __u8  iSerialNumber; */
214 	0x01        /*  __u8  bNumConfigurations; */
215 };
216 
217 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
218 
219 /* usb 1.1 root hub device descriptor */
220 static const u8 usb11_rh_dev_descriptor[18] = {
221 	0x12,       /*  __u8  bLength; */
222 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
223 	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
224 
225 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
226 	0x00,	    /*  __u8  bDeviceSubClass; */
227 	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
228 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
229 
230 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
231 	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
232 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
233 
234 	0x03,       /*  __u8  iManufacturer; */
235 	0x02,       /*  __u8  iProduct; */
236 	0x01,       /*  __u8  iSerialNumber; */
237 	0x01        /*  __u8  bNumConfigurations; */
238 };
239 
240 
241 /*-------------------------------------------------------------------------*/
242 
243 /* Configuration descriptors for our root hubs */
244 
245 static const u8 fs_rh_config_descriptor[] = {
246 
247 	/* one configuration */
248 	0x09,       /*  __u8  bLength; */
249 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
250 	0x19, 0x00, /*  __le16 wTotalLength; */
251 	0x01,       /*  __u8  bNumInterfaces; (1) */
252 	0x01,       /*  __u8  bConfigurationValue; */
253 	0x00,       /*  __u8  iConfiguration; */
254 	0xc0,       /*  __u8  bmAttributes;
255 				 Bit 7: must be set,
256 				     6: Self-powered,
257 				     5: Remote wakeup,
258 				     4..0: resvd */
259 	0x00,       /*  __u8  MaxPower; */
260 
261 	/* USB 1.1:
262 	 * USB 2.0, single TT organization (mandatory):
263 	 *	one interface, protocol 0
264 	 *
265 	 * USB 2.0, multiple TT organization (optional):
266 	 *	two interfaces, protocols 1 (like single TT)
267 	 *	and 2 (multiple TT mode) ... config is
268 	 *	sometimes settable
269 	 *	NOT IMPLEMENTED
270 	 */
271 
272 	/* one interface */
273 	0x09,       /*  __u8  if_bLength; */
274 	USB_DT_INTERFACE,  /* __u8 if_bDescriptorType; Interface */
275 	0x00,       /*  __u8  if_bInterfaceNumber; */
276 	0x00,       /*  __u8  if_bAlternateSetting; */
277 	0x01,       /*  __u8  if_bNumEndpoints; */
278 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
279 	0x00,       /*  __u8  if_bInterfaceSubClass; */
280 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
281 	0x00,       /*  __u8  if_iInterface; */
282 
283 	/* one endpoint (status change endpoint) */
284 	0x07,       /*  __u8  ep_bLength; */
285 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
286 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
287 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
288 	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
289 	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
290 };
291 
292 static const u8 hs_rh_config_descriptor[] = {
293 
294 	/* one configuration */
295 	0x09,       /*  __u8  bLength; */
296 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
297 	0x19, 0x00, /*  __le16 wTotalLength; */
298 	0x01,       /*  __u8  bNumInterfaces; (1) */
299 	0x01,       /*  __u8  bConfigurationValue; */
300 	0x00,       /*  __u8  iConfiguration; */
301 	0xc0,       /*  __u8  bmAttributes;
302 				 Bit 7: must be set,
303 				     6: Self-powered,
304 				     5: Remote wakeup,
305 				     4..0: resvd */
306 	0x00,       /*  __u8  MaxPower; */
307 
308 	/* USB 1.1:
309 	 * USB 2.0, single TT organization (mandatory):
310 	 *	one interface, protocol 0
311 	 *
312 	 * USB 2.0, multiple TT organization (optional):
313 	 *	two interfaces, protocols 1 (like single TT)
314 	 *	and 2 (multiple TT mode) ... config is
315 	 *	sometimes settable
316 	 *	NOT IMPLEMENTED
317 	 */
318 
319 	/* one interface */
320 	0x09,       /*  __u8  if_bLength; */
321 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
322 	0x00,       /*  __u8  if_bInterfaceNumber; */
323 	0x00,       /*  __u8  if_bAlternateSetting; */
324 	0x01,       /*  __u8  if_bNumEndpoints; */
325 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
326 	0x00,       /*  __u8  if_bInterfaceSubClass; */
327 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
328 	0x00,       /*  __u8  if_iInterface; */
329 
330 	/* one endpoint (status change endpoint) */
331 	0x07,       /*  __u8  ep_bLength; */
332 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
333 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
334 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
335 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
336 		     * see hub.c:hub_configure() for details. */
337 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
338 	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
339 };
340 
341 static const u8 ss_rh_config_descriptor[] = {
342 	/* one configuration */
343 	0x09,       /*  __u8  bLength; */
344 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
345 	0x1f, 0x00, /*  __le16 wTotalLength; */
346 	0x01,       /*  __u8  bNumInterfaces; (1) */
347 	0x01,       /*  __u8  bConfigurationValue; */
348 	0x00,       /*  __u8  iConfiguration; */
349 	0xc0,       /*  __u8  bmAttributes;
350 				 Bit 7: must be set,
351 				     6: Self-powered,
352 				     5: Remote wakeup,
353 				     4..0: resvd */
354 	0x00,       /*  __u8  MaxPower; */
355 
356 	/* one interface */
357 	0x09,       /*  __u8  if_bLength; */
358 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
359 	0x00,       /*  __u8  if_bInterfaceNumber; */
360 	0x00,       /*  __u8  if_bAlternateSetting; */
361 	0x01,       /*  __u8  if_bNumEndpoints; */
362 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
363 	0x00,       /*  __u8  if_bInterfaceSubClass; */
364 	0x00,       /*  __u8  if_bInterfaceProtocol; */
365 	0x00,       /*  __u8  if_iInterface; */
366 
367 	/* one endpoint (status change endpoint) */
368 	0x07,       /*  __u8  ep_bLength; */
369 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
370 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
371 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
372 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
373 		     * see hub.c:hub_configure() for details. */
374 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
375 	0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
376 
377 	/* one SuperSpeed endpoint companion descriptor */
378 	0x06,        /* __u8 ss_bLength */
379 	USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */
380 		     /* Companion */
381 	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
382 	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
383 	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
384 };
385 
386 /* authorized_default behaviour:
387  * -1 is authorized for all devices except wireless (old behaviour)
388  * 0 is unauthorized for all devices
389  * 1 is authorized for all devices
390  */
391 static int authorized_default = -1;
392 module_param(authorized_default, int, S_IRUGO|S_IWUSR);
393 MODULE_PARM_DESC(authorized_default,
394 		"Default USB device authorization: 0 is not authorized, 1 is "
395 		"authorized, -1 is authorized except for wireless USB (default, "
396 		"old behaviour");
397 /*-------------------------------------------------------------------------*/
398 
399 /**
400  * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
401  * @s: Null-terminated ASCII (actually ISO-8859-1) string
402  * @buf: Buffer for USB string descriptor (header + UTF-16LE)
403  * @len: Length (in bytes; may be odd) of descriptor buffer.
404  *
405  * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
406  * whichever is less.
407  *
408  * Note:
409  * USB String descriptors can contain at most 126 characters; input
410  * strings longer than that are truncated.
411  */
412 static unsigned
413 ascii2desc(char const *s, u8 *buf, unsigned len)
414 {
415 	unsigned n, t = 2 + 2*strlen(s);
416 
417 	if (t > 254)
418 		t = 254;	/* Longest possible UTF string descriptor */
419 	if (len > t)
420 		len = t;
421 
422 	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
423 
424 	n = len;
425 	while (n--) {
426 		*buf++ = t;
427 		if (!n--)
428 			break;
429 		*buf++ = t >> 8;
430 		t = (unsigned char)*s++;
431 	}
432 	return len;
433 }
434 
435 /**
436  * rh_string() - provides string descriptors for root hub
437  * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
438  * @hcd: the host controller for this root hub
439  * @data: buffer for output packet
440  * @len: length of the provided buffer
441  *
442  * Produces either a manufacturer, product or serial number string for the
443  * virtual root hub device.
444  *
445  * Return: The number of bytes filled in: the length of the descriptor or
446  * of the provided buffer, whichever is less.
447  */
448 static unsigned
449 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
450 {
451 	char buf[100];
452 	char const *s;
453 	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
454 
455 	/* language ids */
456 	switch (id) {
457 	case 0:
458 		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
459 		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
460 		if (len > 4)
461 			len = 4;
462 		memcpy(data, langids, len);
463 		return len;
464 	case 1:
465 		/* Serial number */
466 		s = hcd->self.bus_name;
467 		break;
468 	case 2:
469 		/* Product name */
470 		s = hcd->product_desc;
471 		break;
472 	case 3:
473 		/* Manufacturer */
474 		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
475 			init_utsname()->release, hcd->driver->description);
476 		s = buf;
477 		break;
478 	default:
479 		/* Can't happen; caller guarantees it */
480 		return 0;
481 	}
482 
483 	return ascii2desc(s, data, len);
484 }
485 
486 
487 /* Root hub control transfers execute synchronously */
488 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
489 {
490 	struct usb_ctrlrequest *cmd;
491 	u16		typeReq, wValue, wIndex, wLength;
492 	u8		*ubuf = urb->transfer_buffer;
493 	unsigned	len = 0;
494 	int		status;
495 	u8		patch_wakeup = 0;
496 	u8		patch_protocol = 0;
497 	u16		tbuf_size;
498 	u8		*tbuf = NULL;
499 	const u8	*bufp;
500 
501 	might_sleep();
502 
503 	spin_lock_irq(&hcd_root_hub_lock);
504 	status = usb_hcd_link_urb_to_ep(hcd, urb);
505 	spin_unlock_irq(&hcd_root_hub_lock);
506 	if (status)
507 		return status;
508 	urb->hcpriv = hcd;	/* Indicate it's queued */
509 
510 	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
511 	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
512 	wValue   = le16_to_cpu (cmd->wValue);
513 	wIndex   = le16_to_cpu (cmd->wIndex);
514 	wLength  = le16_to_cpu (cmd->wLength);
515 
516 	if (wLength > urb->transfer_buffer_length)
517 		goto error;
518 
519 	/*
520 	 * tbuf should be at least as big as the
521 	 * USB hub descriptor.
522 	 */
523 	tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
524 	tbuf = kzalloc(tbuf_size, GFP_KERNEL);
525 	if (!tbuf) {
526 		status = -ENOMEM;
527 		goto err_alloc;
528 	}
529 
530 	bufp = tbuf;
531 
532 
533 	urb->actual_length = 0;
534 	switch (typeReq) {
535 
536 	/* DEVICE REQUESTS */
537 
538 	/* The root hub's remote wakeup enable bit is implemented using
539 	 * driver model wakeup flags.  If this system supports wakeup
540 	 * through USB, userspace may change the default "allow wakeup"
541 	 * policy through sysfs or these calls.
542 	 *
543 	 * Most root hubs support wakeup from downstream devices, for
544 	 * runtime power management (disabling USB clocks and reducing
545 	 * VBUS power usage).  However, not all of them do so; silicon,
546 	 * board, and BIOS bugs here are not uncommon, so these can't
547 	 * be treated quite like external hubs.
548 	 *
549 	 * Likewise, not all root hubs will pass wakeup events upstream,
550 	 * to wake up the whole system.  So don't assume root hub and
551 	 * controller capabilities are identical.
552 	 */
553 
554 	case DeviceRequest | USB_REQ_GET_STATUS:
555 		tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
556 					<< USB_DEVICE_REMOTE_WAKEUP)
557 				| (1 << USB_DEVICE_SELF_POWERED);
558 		tbuf[1] = 0;
559 		len = 2;
560 		break;
561 	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
562 		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
563 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
564 		else
565 			goto error;
566 		break;
567 	case DeviceOutRequest | USB_REQ_SET_FEATURE:
568 		if (device_can_wakeup(&hcd->self.root_hub->dev)
569 				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
570 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
571 		else
572 			goto error;
573 		break;
574 	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
575 		tbuf[0] = 1;
576 		len = 1;
577 			/* FALLTHROUGH */
578 	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
579 		break;
580 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
581 		switch (wValue & 0xff00) {
582 		case USB_DT_DEVICE << 8:
583 			switch (hcd->speed) {
584 			case HCD_USB31:
585 				bufp = usb31_rh_dev_descriptor;
586 				break;
587 			case HCD_USB3:
588 				bufp = usb3_rh_dev_descriptor;
589 				break;
590 			case HCD_USB25:
591 				bufp = usb25_rh_dev_descriptor;
592 				break;
593 			case HCD_USB2:
594 				bufp = usb2_rh_dev_descriptor;
595 				break;
596 			case HCD_USB11:
597 				bufp = usb11_rh_dev_descriptor;
598 				break;
599 			default:
600 				goto error;
601 			}
602 			len = 18;
603 			if (hcd->has_tt)
604 				patch_protocol = 1;
605 			break;
606 		case USB_DT_CONFIG << 8:
607 			switch (hcd->speed) {
608 			case HCD_USB31:
609 			case HCD_USB3:
610 				bufp = ss_rh_config_descriptor;
611 				len = sizeof ss_rh_config_descriptor;
612 				break;
613 			case HCD_USB25:
614 			case HCD_USB2:
615 				bufp = hs_rh_config_descriptor;
616 				len = sizeof hs_rh_config_descriptor;
617 				break;
618 			case HCD_USB11:
619 				bufp = fs_rh_config_descriptor;
620 				len = sizeof fs_rh_config_descriptor;
621 				break;
622 			default:
623 				goto error;
624 			}
625 			if (device_can_wakeup(&hcd->self.root_hub->dev))
626 				patch_wakeup = 1;
627 			break;
628 		case USB_DT_STRING << 8:
629 			if ((wValue & 0xff) < 4)
630 				urb->actual_length = rh_string(wValue & 0xff,
631 						hcd, ubuf, wLength);
632 			else /* unsupported IDs --> "protocol stall" */
633 				goto error;
634 			break;
635 		case USB_DT_BOS << 8:
636 			goto nongeneric;
637 		default:
638 			goto error;
639 		}
640 		break;
641 	case DeviceRequest | USB_REQ_GET_INTERFACE:
642 		tbuf[0] = 0;
643 		len = 1;
644 			/* FALLTHROUGH */
645 	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
646 		break;
647 	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
648 		/* wValue == urb->dev->devaddr */
649 		dev_dbg (hcd->self.controller, "root hub device address %d\n",
650 			wValue);
651 		break;
652 
653 	/* INTERFACE REQUESTS (no defined feature/status flags) */
654 
655 	/* ENDPOINT REQUESTS */
656 
657 	case EndpointRequest | USB_REQ_GET_STATUS:
658 		/* ENDPOINT_HALT flag */
659 		tbuf[0] = 0;
660 		tbuf[1] = 0;
661 		len = 2;
662 			/* FALLTHROUGH */
663 	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
664 	case EndpointOutRequest | USB_REQ_SET_FEATURE:
665 		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
666 		break;
667 
668 	/* CLASS REQUESTS (and errors) */
669 
670 	default:
671 nongeneric:
672 		/* non-generic request */
673 		switch (typeReq) {
674 		case GetHubStatus:
675 			len = 4;
676 			break;
677 		case GetPortStatus:
678 			if (wValue == HUB_PORT_STATUS)
679 				len = 4;
680 			else
681 				/* other port status types return 8 bytes */
682 				len = 8;
683 			break;
684 		case GetHubDescriptor:
685 			len = sizeof (struct usb_hub_descriptor);
686 			break;
687 		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
688 			/* len is returned by hub_control */
689 			break;
690 		}
691 		status = hcd->driver->hub_control (hcd,
692 			typeReq, wValue, wIndex,
693 			tbuf, wLength);
694 
695 		if (typeReq == GetHubDescriptor)
696 			usb_hub_adjust_deviceremovable(hcd->self.root_hub,
697 				(struct usb_hub_descriptor *)tbuf);
698 		break;
699 error:
700 		/* "protocol stall" on error */
701 		status = -EPIPE;
702 	}
703 
704 	if (status < 0) {
705 		len = 0;
706 		if (status != -EPIPE) {
707 			dev_dbg (hcd->self.controller,
708 				"CTRL: TypeReq=0x%x val=0x%x "
709 				"idx=0x%x len=%d ==> %d\n",
710 				typeReq, wValue, wIndex,
711 				wLength, status);
712 		}
713 	} else if (status > 0) {
714 		/* hub_control may return the length of data copied. */
715 		len = status;
716 		status = 0;
717 	}
718 	if (len) {
719 		if (urb->transfer_buffer_length < len)
720 			len = urb->transfer_buffer_length;
721 		urb->actual_length = len;
722 		/* always USB_DIR_IN, toward host */
723 		memcpy (ubuf, bufp, len);
724 
725 		/* report whether RH hardware supports remote wakeup */
726 		if (patch_wakeup &&
727 				len > offsetof (struct usb_config_descriptor,
728 						bmAttributes))
729 			((struct usb_config_descriptor *)ubuf)->bmAttributes
730 				|= USB_CONFIG_ATT_WAKEUP;
731 
732 		/* report whether RH hardware has an integrated TT */
733 		if (patch_protocol &&
734 				len > offsetof(struct usb_device_descriptor,
735 						bDeviceProtocol))
736 			((struct usb_device_descriptor *) ubuf)->
737 				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
738 	}
739 
740 	kfree(tbuf);
741  err_alloc:
742 
743 	/* any errors get returned through the urb completion */
744 	spin_lock_irq(&hcd_root_hub_lock);
745 	usb_hcd_unlink_urb_from_ep(hcd, urb);
746 	usb_hcd_giveback_urb(hcd, urb, status);
747 	spin_unlock_irq(&hcd_root_hub_lock);
748 	return 0;
749 }
750 
751 /*-------------------------------------------------------------------------*/
752 
753 /*
754  * Root Hub interrupt transfers are polled using a timer if the
755  * driver requests it; otherwise the driver is responsible for
756  * calling usb_hcd_poll_rh_status() when an event occurs.
757  *
758  * Completions are called in_interrupt(), but they may or may not
759  * be in_irq().
760  */
761 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
762 {
763 	struct urb	*urb;
764 	int		length;
765 	unsigned long	flags;
766 	char		buffer[6];	/* Any root hubs with > 31 ports? */
767 
768 	if (unlikely(!hcd->rh_pollable))
769 		return;
770 	if (!hcd->uses_new_polling && !hcd->status_urb)
771 		return;
772 
773 	length = hcd->driver->hub_status_data(hcd, buffer);
774 	if (length > 0) {
775 
776 		/* try to complete the status urb */
777 		spin_lock_irqsave(&hcd_root_hub_lock, flags);
778 		urb = hcd->status_urb;
779 		if (urb) {
780 			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
781 			hcd->status_urb = NULL;
782 			urb->actual_length = length;
783 			memcpy(urb->transfer_buffer, buffer, length);
784 
785 			usb_hcd_unlink_urb_from_ep(hcd, urb);
786 			usb_hcd_giveback_urb(hcd, urb, 0);
787 		} else {
788 			length = 0;
789 			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
790 		}
791 		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
792 	}
793 
794 	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
795 	 * exceed that limit if HZ is 100. The math is more clunky than
796 	 * maybe expected, this is to make sure that all timers for USB devices
797 	 * fire at the same time to give the CPU a break in between */
798 	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
799 			(length == 0 && hcd->status_urb != NULL))
800 		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
801 }
802 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
803 
804 /* timer callback */
805 static void rh_timer_func (unsigned long _hcd)
806 {
807 	usb_hcd_poll_rh_status((struct usb_hcd *) _hcd);
808 }
809 
810 /*-------------------------------------------------------------------------*/
811 
812 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
813 {
814 	int		retval;
815 	unsigned long	flags;
816 	unsigned	len = 1 + (urb->dev->maxchild / 8);
817 
818 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
819 	if (hcd->status_urb || urb->transfer_buffer_length < len) {
820 		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
821 		retval = -EINVAL;
822 		goto done;
823 	}
824 
825 	retval = usb_hcd_link_urb_to_ep(hcd, urb);
826 	if (retval)
827 		goto done;
828 
829 	hcd->status_urb = urb;
830 	urb->hcpriv = hcd;	/* indicate it's queued */
831 	if (!hcd->uses_new_polling)
832 		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
833 
834 	/* If a status change has already occurred, report it ASAP */
835 	else if (HCD_POLL_PENDING(hcd))
836 		mod_timer(&hcd->rh_timer, jiffies);
837 	retval = 0;
838  done:
839 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
840 	return retval;
841 }
842 
843 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
844 {
845 	if (usb_endpoint_xfer_int(&urb->ep->desc))
846 		return rh_queue_status (hcd, urb);
847 	if (usb_endpoint_xfer_control(&urb->ep->desc))
848 		return rh_call_control (hcd, urb);
849 	return -EINVAL;
850 }
851 
852 /*-------------------------------------------------------------------------*/
853 
854 /* Unlinks of root-hub control URBs are legal, but they don't do anything
855  * since these URBs always execute synchronously.
856  */
857 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
858 {
859 	unsigned long	flags;
860 	int		rc;
861 
862 	spin_lock_irqsave(&hcd_root_hub_lock, flags);
863 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
864 	if (rc)
865 		goto done;
866 
867 	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
868 		;	/* Do nothing */
869 
870 	} else {				/* Status URB */
871 		if (!hcd->uses_new_polling)
872 			del_timer (&hcd->rh_timer);
873 		if (urb == hcd->status_urb) {
874 			hcd->status_urb = NULL;
875 			usb_hcd_unlink_urb_from_ep(hcd, urb);
876 			usb_hcd_giveback_urb(hcd, urb, status);
877 		}
878 	}
879  done:
880 	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
881 	return rc;
882 }
883 
884 
885 
886 /*
887  * Show & store the current value of authorized_default
888  */
889 static ssize_t authorized_default_show(struct device *dev,
890 				       struct device_attribute *attr, char *buf)
891 {
892 	struct usb_device *rh_usb_dev = to_usb_device(dev);
893 	struct usb_bus *usb_bus = rh_usb_dev->bus;
894 	struct usb_hcd *hcd;
895 
896 	hcd = bus_to_hcd(usb_bus);
897 	return snprintf(buf, PAGE_SIZE, "%u\n", !!HCD_DEV_AUTHORIZED(hcd));
898 }
899 
900 static ssize_t authorized_default_store(struct device *dev,
901 					struct device_attribute *attr,
902 					const char *buf, size_t size)
903 {
904 	ssize_t result;
905 	unsigned val;
906 	struct usb_device *rh_usb_dev = to_usb_device(dev);
907 	struct usb_bus *usb_bus = rh_usb_dev->bus;
908 	struct usb_hcd *hcd;
909 
910 	hcd = bus_to_hcd(usb_bus);
911 	result = sscanf(buf, "%u\n", &val);
912 	if (result == 1) {
913 		if (val)
914 			set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
915 		else
916 			clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
917 
918 		result = size;
919 	} else {
920 		result = -EINVAL;
921 	}
922 	return result;
923 }
924 static DEVICE_ATTR_RW(authorized_default);
925 
926 /*
927  * interface_authorized_default_show - show default authorization status
928  * for USB interfaces
929  *
930  * note: interface_authorized_default is the default value
931  *       for initializing the authorized attribute of interfaces
932  */
933 static ssize_t interface_authorized_default_show(struct device *dev,
934 		struct device_attribute *attr, char *buf)
935 {
936 	struct usb_device *usb_dev = to_usb_device(dev);
937 	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
938 
939 	return sprintf(buf, "%u\n", !!HCD_INTF_AUTHORIZED(hcd));
940 }
941 
942 /*
943  * interface_authorized_default_store - store default authorization status
944  * for USB interfaces
945  *
946  * note: interface_authorized_default is the default value
947  *       for initializing the authorized attribute of interfaces
948  */
949 static ssize_t interface_authorized_default_store(struct device *dev,
950 		struct device_attribute *attr, const char *buf, size_t count)
951 {
952 	struct usb_device *usb_dev = to_usb_device(dev);
953 	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
954 	int rc = count;
955 	bool val;
956 
957 	if (strtobool(buf, &val) != 0)
958 		return -EINVAL;
959 
960 	if (val)
961 		set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
962 	else
963 		clear_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
964 
965 	return rc;
966 }
967 static DEVICE_ATTR_RW(interface_authorized_default);
968 
969 /* Group all the USB bus attributes */
970 static struct attribute *usb_bus_attrs[] = {
971 		&dev_attr_authorized_default.attr,
972 		&dev_attr_interface_authorized_default.attr,
973 		NULL,
974 };
975 
976 static const struct attribute_group usb_bus_attr_group = {
977 	.name = NULL,	/* we want them in the same directory */
978 	.attrs = usb_bus_attrs,
979 };
980 
981 
982 
983 /*-------------------------------------------------------------------------*/
984 
985 /**
986  * usb_bus_init - shared initialization code
987  * @bus: the bus structure being initialized
988  *
989  * This code is used to initialize a usb_bus structure, memory for which is
990  * separately managed.
991  */
992 static void usb_bus_init (struct usb_bus *bus)
993 {
994 	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
995 
996 	bus->devnum_next = 1;
997 
998 	bus->root_hub = NULL;
999 	bus->busnum = -1;
1000 	bus->bandwidth_allocated = 0;
1001 	bus->bandwidth_int_reqs  = 0;
1002 	bus->bandwidth_isoc_reqs = 0;
1003 	mutex_init(&bus->devnum_next_mutex);
1004 }
1005 
1006 /*-------------------------------------------------------------------------*/
1007 
1008 /**
1009  * usb_register_bus - registers the USB host controller with the usb core
1010  * @bus: pointer to the bus to register
1011  * Context: !in_interrupt()
1012  *
1013  * Assigns a bus number, and links the controller into usbcore data
1014  * structures so that it can be seen by scanning the bus list.
1015  *
1016  * Return: 0 if successful. A negative error code otherwise.
1017  */
1018 static int usb_register_bus(struct usb_bus *bus)
1019 {
1020 	int result = -E2BIG;
1021 	int busnum;
1022 
1023 	mutex_lock(&usb_bus_idr_lock);
1024 	busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL);
1025 	if (busnum < 0) {
1026 		pr_err("%s: failed to get bus number\n", usbcore_name);
1027 		goto error_find_busnum;
1028 	}
1029 	bus->busnum = busnum;
1030 	mutex_unlock(&usb_bus_idr_lock);
1031 
1032 	usb_notify_add_bus(bus);
1033 
1034 	dev_info (bus->controller, "new USB bus registered, assigned bus "
1035 		  "number %d\n", bus->busnum);
1036 	return 0;
1037 
1038 error_find_busnum:
1039 	mutex_unlock(&usb_bus_idr_lock);
1040 	return result;
1041 }
1042 
1043 /**
1044  * usb_deregister_bus - deregisters the USB host controller
1045  * @bus: pointer to the bus to deregister
1046  * Context: !in_interrupt()
1047  *
1048  * Recycles the bus number, and unlinks the controller from usbcore data
1049  * structures so that it won't be seen by scanning the bus list.
1050  */
1051 static void usb_deregister_bus (struct usb_bus *bus)
1052 {
1053 	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
1054 
1055 	/*
1056 	 * NOTE: make sure that all the devices are removed by the
1057 	 * controller code, as well as having it call this when cleaning
1058 	 * itself up
1059 	 */
1060 	mutex_lock(&usb_bus_idr_lock);
1061 	idr_remove(&usb_bus_idr, bus->busnum);
1062 	mutex_unlock(&usb_bus_idr_lock);
1063 
1064 	usb_notify_remove_bus(bus);
1065 }
1066 
1067 /**
1068  * register_root_hub - called by usb_add_hcd() to register a root hub
1069  * @hcd: host controller for this root hub
1070  *
1071  * This function registers the root hub with the USB subsystem.  It sets up
1072  * the device properly in the device tree and then calls usb_new_device()
1073  * to register the usb device.  It also assigns the root hub's USB address
1074  * (always 1).
1075  *
1076  * Return: 0 if successful. A negative error code otherwise.
1077  */
1078 static int register_root_hub(struct usb_hcd *hcd)
1079 {
1080 	struct device *parent_dev = hcd->self.controller;
1081 	struct usb_device *usb_dev = hcd->self.root_hub;
1082 	const int devnum = 1;
1083 	int retval;
1084 
1085 	usb_dev->devnum = devnum;
1086 	usb_dev->bus->devnum_next = devnum + 1;
1087 	memset (&usb_dev->bus->devmap.devicemap, 0,
1088 			sizeof usb_dev->bus->devmap.devicemap);
1089 	set_bit (devnum, usb_dev->bus->devmap.devicemap);
1090 	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
1091 
1092 	mutex_lock(&usb_bus_idr_lock);
1093 
1094 	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
1095 	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
1096 	if (retval != sizeof usb_dev->descriptor) {
1097 		mutex_unlock(&usb_bus_idr_lock);
1098 		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
1099 				dev_name(&usb_dev->dev), retval);
1100 		return (retval < 0) ? retval : -EMSGSIZE;
1101 	}
1102 
1103 	if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
1104 		retval = usb_get_bos_descriptor(usb_dev);
1105 		if (!retval) {
1106 			usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
1107 		} else if (usb_dev->speed >= USB_SPEED_SUPER) {
1108 			mutex_unlock(&usb_bus_idr_lock);
1109 			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1110 					dev_name(&usb_dev->dev), retval);
1111 			return retval;
1112 		}
1113 	}
1114 
1115 	retval = usb_new_device (usb_dev);
1116 	if (retval) {
1117 		dev_err (parent_dev, "can't register root hub for %s, %d\n",
1118 				dev_name(&usb_dev->dev), retval);
1119 	} else {
1120 		spin_lock_irq (&hcd_root_hub_lock);
1121 		hcd->rh_registered = 1;
1122 		spin_unlock_irq (&hcd_root_hub_lock);
1123 
1124 		/* Did the HC die before the root hub was registered? */
1125 		if (HCD_DEAD(hcd))
1126 			usb_hc_died (hcd);	/* This time clean up */
1127 	}
1128 	mutex_unlock(&usb_bus_idr_lock);
1129 
1130 	return retval;
1131 }
1132 
1133 /*
1134  * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1135  * @bus: the bus which the root hub belongs to
1136  * @portnum: the port which is being resumed
1137  *
1138  * HCDs should call this function when they know that a resume signal is
1139  * being sent to a root-hub port.  The root hub will be prevented from
1140  * going into autosuspend until usb_hcd_end_port_resume() is called.
1141  *
1142  * The bus's private lock must be held by the caller.
1143  */
1144 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1145 {
1146 	unsigned bit = 1 << portnum;
1147 
1148 	if (!(bus->resuming_ports & bit)) {
1149 		bus->resuming_ports |= bit;
1150 		pm_runtime_get_noresume(&bus->root_hub->dev);
1151 	}
1152 }
1153 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1154 
1155 /*
1156  * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1157  * @bus: the bus which the root hub belongs to
1158  * @portnum: the port which is being resumed
1159  *
1160  * HCDs should call this function when they know that a resume signal has
1161  * stopped being sent to a root-hub port.  The root hub will be allowed to
1162  * autosuspend again.
1163  *
1164  * The bus's private lock must be held by the caller.
1165  */
1166 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1167 {
1168 	unsigned bit = 1 << portnum;
1169 
1170 	if (bus->resuming_ports & bit) {
1171 		bus->resuming_ports &= ~bit;
1172 		pm_runtime_put_noidle(&bus->root_hub->dev);
1173 	}
1174 }
1175 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1176 
1177 /*-------------------------------------------------------------------------*/
1178 
1179 /**
1180  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1181  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1182  * @is_input: true iff the transaction sends data to the host
1183  * @isoc: true for isochronous transactions, false for interrupt ones
1184  * @bytecount: how many bytes in the transaction.
1185  *
1186  * Return: Approximate bus time in nanoseconds for a periodic transaction.
1187  *
1188  * Note:
1189  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1190  * scheduled in software, this function is only used for such scheduling.
1191  */
1192 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1193 {
1194 	unsigned long	tmp;
1195 
1196 	switch (speed) {
1197 	case USB_SPEED_LOW: 	/* INTR only */
1198 		if (is_input) {
1199 			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1200 			return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1201 		} else {
1202 			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1203 			return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1204 		}
1205 	case USB_SPEED_FULL:	/* ISOC or INTR */
1206 		if (isoc) {
1207 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1208 			return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1209 		} else {
1210 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1211 			return 9107L + BW_HOST_DELAY + tmp;
1212 		}
1213 	case USB_SPEED_HIGH:	/* ISOC or INTR */
1214 		/* FIXME adjust for input vs output */
1215 		if (isoc)
1216 			tmp = HS_NSECS_ISO (bytecount);
1217 		else
1218 			tmp = HS_NSECS (bytecount);
1219 		return tmp;
1220 	default:
1221 		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1222 		return -1;
1223 	}
1224 }
1225 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1226 
1227 
1228 /*-------------------------------------------------------------------------*/
1229 
1230 /*
1231  * Generic HC operations.
1232  */
1233 
1234 /*-------------------------------------------------------------------------*/
1235 
1236 /**
1237  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1238  * @hcd: host controller to which @urb was submitted
1239  * @urb: URB being submitted
1240  *
1241  * Host controller drivers should call this routine in their enqueue()
1242  * method.  The HCD's private spinlock must be held and interrupts must
1243  * be disabled.  The actions carried out here are required for URB
1244  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1245  *
1246  * Return: 0 for no error, otherwise a negative error code (in which case
1247  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1248  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1249  * the private spinlock and returning.
1250  */
1251 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1252 {
1253 	int		rc = 0;
1254 
1255 	spin_lock(&hcd_urb_list_lock);
1256 
1257 	/* Check that the URB isn't being killed */
1258 	if (unlikely(atomic_read(&urb->reject))) {
1259 		rc = -EPERM;
1260 		goto done;
1261 	}
1262 
1263 	if (unlikely(!urb->ep->enabled)) {
1264 		rc = -ENOENT;
1265 		goto done;
1266 	}
1267 
1268 	if (unlikely(!urb->dev->can_submit)) {
1269 		rc = -EHOSTUNREACH;
1270 		goto done;
1271 	}
1272 
1273 	/*
1274 	 * Check the host controller's state and add the URB to the
1275 	 * endpoint's queue.
1276 	 */
1277 	if (HCD_RH_RUNNING(hcd)) {
1278 		urb->unlinked = 0;
1279 		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1280 	} else {
1281 		rc = -ESHUTDOWN;
1282 		goto done;
1283 	}
1284  done:
1285 	spin_unlock(&hcd_urb_list_lock);
1286 	return rc;
1287 }
1288 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1289 
1290 /**
1291  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1292  * @hcd: host controller to which @urb was submitted
1293  * @urb: URB being checked for unlinkability
1294  * @status: error code to store in @urb if the unlink succeeds
1295  *
1296  * Host controller drivers should call this routine in their dequeue()
1297  * method.  The HCD's private spinlock must be held and interrupts must
1298  * be disabled.  The actions carried out here are required for making
1299  * sure than an unlink is valid.
1300  *
1301  * Return: 0 for no error, otherwise a negative error code (in which case
1302  * the dequeue() method must fail).  The possible error codes are:
1303  *
1304  *	-EIDRM: @urb was not submitted or has already completed.
1305  *		The completion function may not have been called yet.
1306  *
1307  *	-EBUSY: @urb has already been unlinked.
1308  */
1309 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1310 		int status)
1311 {
1312 	struct list_head	*tmp;
1313 
1314 	/* insist the urb is still queued */
1315 	list_for_each(tmp, &urb->ep->urb_list) {
1316 		if (tmp == &urb->urb_list)
1317 			break;
1318 	}
1319 	if (tmp != &urb->urb_list)
1320 		return -EIDRM;
1321 
1322 	/* Any status except -EINPROGRESS means something already started to
1323 	 * unlink this URB from the hardware.  So there's no more work to do.
1324 	 */
1325 	if (urb->unlinked)
1326 		return -EBUSY;
1327 	urb->unlinked = status;
1328 	return 0;
1329 }
1330 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1331 
1332 /**
1333  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1334  * @hcd: host controller to which @urb was submitted
1335  * @urb: URB being unlinked
1336  *
1337  * Host controller drivers should call this routine before calling
1338  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1339  * interrupts must be disabled.  The actions carried out here are required
1340  * for URB completion.
1341  */
1342 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1343 {
1344 	/* clear all state linking urb to this dev (and hcd) */
1345 	spin_lock(&hcd_urb_list_lock);
1346 	list_del_init(&urb->urb_list);
1347 	spin_unlock(&hcd_urb_list_lock);
1348 }
1349 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1350 
1351 /*
1352  * Some usb host controllers can only perform dma using a small SRAM area.
1353  * The usb core itself is however optimized for host controllers that can dma
1354  * using regular system memory - like pci devices doing bus mastering.
1355  *
1356  * To support host controllers with limited dma capabilities we provide dma
1357  * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag.
1358  * For this to work properly the host controller code must first use the
1359  * function dma_declare_coherent_memory() to point out which memory area
1360  * that should be used for dma allocations.
1361  *
1362  * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for
1363  * dma using dma_alloc_coherent() which in turn allocates from the memory
1364  * area pointed out with dma_declare_coherent_memory().
1365  *
1366  * So, to summarize...
1367  *
1368  * - We need "local" memory, canonical example being
1369  *   a small SRAM on a discrete controller being the
1370  *   only memory that the controller can read ...
1371  *   (a) "normal" kernel memory is no good, and
1372  *   (b) there's not enough to share
1373  *
1374  * - The only *portable* hook for such stuff in the
1375  *   DMA framework is dma_declare_coherent_memory()
1376  *
1377  * - So we use that, even though the primary requirement
1378  *   is that the memory be "local" (hence addressable
1379  *   by that device), not "coherent".
1380  *
1381  */
1382 
1383 static int hcd_alloc_coherent(struct usb_bus *bus,
1384 			      gfp_t mem_flags, dma_addr_t *dma_handle,
1385 			      void **vaddr_handle, size_t size,
1386 			      enum dma_data_direction dir)
1387 {
1388 	unsigned char *vaddr;
1389 
1390 	if (*vaddr_handle == NULL) {
1391 		WARN_ON_ONCE(1);
1392 		return -EFAULT;
1393 	}
1394 
1395 	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1396 				 mem_flags, dma_handle);
1397 	if (!vaddr)
1398 		return -ENOMEM;
1399 
1400 	/*
1401 	 * Store the virtual address of the buffer at the end
1402 	 * of the allocated dma buffer. The size of the buffer
1403 	 * may be uneven so use unaligned functions instead
1404 	 * of just rounding up. It makes sense to optimize for
1405 	 * memory footprint over access speed since the amount
1406 	 * of memory available for dma may be limited.
1407 	 */
1408 	put_unaligned((unsigned long)*vaddr_handle,
1409 		      (unsigned long *)(vaddr + size));
1410 
1411 	if (dir == DMA_TO_DEVICE)
1412 		memcpy(vaddr, *vaddr_handle, size);
1413 
1414 	*vaddr_handle = vaddr;
1415 	return 0;
1416 }
1417 
1418 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1419 			      void **vaddr_handle, size_t size,
1420 			      enum dma_data_direction dir)
1421 {
1422 	unsigned char *vaddr = *vaddr_handle;
1423 
1424 	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1425 
1426 	if (dir == DMA_FROM_DEVICE)
1427 		memcpy(vaddr, *vaddr_handle, size);
1428 
1429 	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1430 
1431 	*vaddr_handle = vaddr;
1432 	*dma_handle = 0;
1433 }
1434 
1435 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1436 {
1437 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1438 	    (urb->transfer_flags & URB_SETUP_MAP_SINGLE))
1439 		dma_unmap_single(hcd->self.sysdev,
1440 				urb->setup_dma,
1441 				sizeof(struct usb_ctrlrequest),
1442 				DMA_TO_DEVICE);
1443 	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1444 		hcd_free_coherent(urb->dev->bus,
1445 				&urb->setup_dma,
1446 				(void **) &urb->setup_packet,
1447 				sizeof(struct usb_ctrlrequest),
1448 				DMA_TO_DEVICE);
1449 
1450 	/* Make it safe to call this routine more than once */
1451 	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1452 }
1453 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1454 
1455 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1456 {
1457 	if (hcd->driver->unmap_urb_for_dma)
1458 		hcd->driver->unmap_urb_for_dma(hcd, urb);
1459 	else
1460 		usb_hcd_unmap_urb_for_dma(hcd, urb);
1461 }
1462 
1463 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1464 {
1465 	enum dma_data_direction dir;
1466 
1467 	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1468 
1469 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1470 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1471 	    (urb->transfer_flags & URB_DMA_MAP_SG))
1472 		dma_unmap_sg(hcd->self.sysdev,
1473 				urb->sg,
1474 				urb->num_sgs,
1475 				dir);
1476 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1477 		 (urb->transfer_flags & URB_DMA_MAP_PAGE))
1478 		dma_unmap_page(hcd->self.sysdev,
1479 				urb->transfer_dma,
1480 				urb->transfer_buffer_length,
1481 				dir);
1482 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1483 		 (urb->transfer_flags & URB_DMA_MAP_SINGLE))
1484 		dma_unmap_single(hcd->self.sysdev,
1485 				urb->transfer_dma,
1486 				urb->transfer_buffer_length,
1487 				dir);
1488 	else if (urb->transfer_flags & URB_MAP_LOCAL)
1489 		hcd_free_coherent(urb->dev->bus,
1490 				&urb->transfer_dma,
1491 				&urb->transfer_buffer,
1492 				urb->transfer_buffer_length,
1493 				dir);
1494 
1495 	/* Make it safe to call this routine more than once */
1496 	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1497 			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1498 }
1499 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1500 
1501 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1502 			   gfp_t mem_flags)
1503 {
1504 	if (hcd->driver->map_urb_for_dma)
1505 		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1506 	else
1507 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1508 }
1509 
1510 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1511 			    gfp_t mem_flags)
1512 {
1513 	enum dma_data_direction dir;
1514 	int ret = 0;
1515 
1516 	/* Map the URB's buffers for DMA access.
1517 	 * Lower level HCD code should use *_dma exclusively,
1518 	 * unless it uses pio or talks to another transport,
1519 	 * or uses the provided scatter gather list for bulk.
1520 	 */
1521 
1522 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1523 		if (hcd->self.uses_pio_for_control)
1524 			return ret;
1525 		if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) {
1526 			if (is_vmalloc_addr(urb->setup_packet)) {
1527 				WARN_ONCE(1, "setup packet is not dma capable\n");
1528 				return -EAGAIN;
1529 			} else if (object_is_on_stack(urb->setup_packet)) {
1530 				WARN_ONCE(1, "setup packet is on stack\n");
1531 				return -EAGAIN;
1532 			}
1533 
1534 			urb->setup_dma = dma_map_single(
1535 					hcd->self.sysdev,
1536 					urb->setup_packet,
1537 					sizeof(struct usb_ctrlrequest),
1538 					DMA_TO_DEVICE);
1539 			if (dma_mapping_error(hcd->self.sysdev,
1540 						urb->setup_dma))
1541 				return -EAGAIN;
1542 			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1543 		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1544 			ret = hcd_alloc_coherent(
1545 					urb->dev->bus, mem_flags,
1546 					&urb->setup_dma,
1547 					(void **)&urb->setup_packet,
1548 					sizeof(struct usb_ctrlrequest),
1549 					DMA_TO_DEVICE);
1550 			if (ret)
1551 				return ret;
1552 			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1553 		}
1554 	}
1555 
1556 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1557 	if (urb->transfer_buffer_length != 0
1558 	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1559 		if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) {
1560 			if (urb->num_sgs) {
1561 				int n;
1562 
1563 				/* We don't support sg for isoc transfers ! */
1564 				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1565 					WARN_ON(1);
1566 					return -EINVAL;
1567 				}
1568 
1569 				n = dma_map_sg(
1570 						hcd->self.sysdev,
1571 						urb->sg,
1572 						urb->num_sgs,
1573 						dir);
1574 				if (n <= 0)
1575 					ret = -EAGAIN;
1576 				else
1577 					urb->transfer_flags |= URB_DMA_MAP_SG;
1578 				urb->num_mapped_sgs = n;
1579 				if (n != urb->num_sgs)
1580 					urb->transfer_flags |=
1581 							URB_DMA_SG_COMBINED;
1582 			} else if (urb->sg) {
1583 				struct scatterlist *sg = urb->sg;
1584 				urb->transfer_dma = dma_map_page(
1585 						hcd->self.sysdev,
1586 						sg_page(sg),
1587 						sg->offset,
1588 						urb->transfer_buffer_length,
1589 						dir);
1590 				if (dma_mapping_error(hcd->self.sysdev,
1591 						urb->transfer_dma))
1592 					ret = -EAGAIN;
1593 				else
1594 					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1595 			} else if (is_vmalloc_addr(urb->transfer_buffer)) {
1596 				WARN_ONCE(1, "transfer buffer not dma capable\n");
1597 				ret = -EAGAIN;
1598 			} else if (object_is_on_stack(urb->transfer_buffer)) {
1599 				WARN_ONCE(1, "transfer buffer is on stack\n");
1600 				ret = -EAGAIN;
1601 			} else {
1602 				urb->transfer_dma = dma_map_single(
1603 						hcd->self.sysdev,
1604 						urb->transfer_buffer,
1605 						urb->transfer_buffer_length,
1606 						dir);
1607 				if (dma_mapping_error(hcd->self.sysdev,
1608 						urb->transfer_dma))
1609 					ret = -EAGAIN;
1610 				else
1611 					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1612 			}
1613 		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1614 			ret = hcd_alloc_coherent(
1615 					urb->dev->bus, mem_flags,
1616 					&urb->transfer_dma,
1617 					&urb->transfer_buffer,
1618 					urb->transfer_buffer_length,
1619 					dir);
1620 			if (ret == 0)
1621 				urb->transfer_flags |= URB_MAP_LOCAL;
1622 		}
1623 		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1624 				URB_SETUP_MAP_LOCAL)))
1625 			usb_hcd_unmap_urb_for_dma(hcd, urb);
1626 	}
1627 	return ret;
1628 }
1629 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1630 
1631 /*-------------------------------------------------------------------------*/
1632 
1633 /* may be called in any context with a valid urb->dev usecount
1634  * caller surrenders "ownership" of urb
1635  * expects usb_submit_urb() to have sanity checked and conditioned all
1636  * inputs in the urb
1637  */
1638 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1639 {
1640 	int			status;
1641 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1642 
1643 	/* increment urb's reference count as part of giving it to the HCD
1644 	 * (which will control it).  HCD guarantees that it either returns
1645 	 * an error or calls giveback(), but not both.
1646 	 */
1647 	usb_get_urb(urb);
1648 	atomic_inc(&urb->use_count);
1649 	atomic_inc(&urb->dev->urbnum);
1650 	usbmon_urb_submit(&hcd->self, urb);
1651 
1652 	/* NOTE requirements on root-hub callers (usbfs and the hub
1653 	 * driver, for now):  URBs' urb->transfer_buffer must be
1654 	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1655 	 * they could clobber root hub response data.  Also, control
1656 	 * URBs must be submitted in process context with interrupts
1657 	 * enabled.
1658 	 */
1659 
1660 	if (is_root_hub(urb->dev)) {
1661 		status = rh_urb_enqueue(hcd, urb);
1662 	} else {
1663 		status = map_urb_for_dma(hcd, urb, mem_flags);
1664 		if (likely(status == 0)) {
1665 			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1666 			if (unlikely(status))
1667 				unmap_urb_for_dma(hcd, urb);
1668 		}
1669 	}
1670 
1671 	if (unlikely(status)) {
1672 		usbmon_urb_submit_error(&hcd->self, urb, status);
1673 		urb->hcpriv = NULL;
1674 		INIT_LIST_HEAD(&urb->urb_list);
1675 		atomic_dec(&urb->use_count);
1676 		atomic_dec(&urb->dev->urbnum);
1677 		if (atomic_read(&urb->reject))
1678 			wake_up(&usb_kill_urb_queue);
1679 		usb_put_urb(urb);
1680 	}
1681 	return status;
1682 }
1683 
1684 /*-------------------------------------------------------------------------*/
1685 
1686 /* this makes the hcd giveback() the urb more quickly, by kicking it
1687  * off hardware queues (which may take a while) and returning it as
1688  * soon as practical.  we've already set up the urb's return status,
1689  * but we can't know if the callback completed already.
1690  */
1691 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1692 {
1693 	int		value;
1694 
1695 	if (is_root_hub(urb->dev))
1696 		value = usb_rh_urb_dequeue(hcd, urb, status);
1697 	else {
1698 
1699 		/* The only reason an HCD might fail this call is if
1700 		 * it has not yet fully queued the urb to begin with.
1701 		 * Such failures should be harmless. */
1702 		value = hcd->driver->urb_dequeue(hcd, urb, status);
1703 	}
1704 	return value;
1705 }
1706 
1707 /*
1708  * called in any context
1709  *
1710  * caller guarantees urb won't be recycled till both unlink()
1711  * and the urb's completion function return
1712  */
1713 int usb_hcd_unlink_urb (struct urb *urb, int status)
1714 {
1715 	struct usb_hcd		*hcd;
1716 	struct usb_device	*udev = urb->dev;
1717 	int			retval = -EIDRM;
1718 	unsigned long		flags;
1719 
1720 	/* Prevent the device and bus from going away while
1721 	 * the unlink is carried out.  If they are already gone
1722 	 * then urb->use_count must be 0, since disconnected
1723 	 * devices can't have any active URBs.
1724 	 */
1725 	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1726 	if (atomic_read(&urb->use_count) > 0) {
1727 		retval = 0;
1728 		usb_get_dev(udev);
1729 	}
1730 	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1731 	if (retval == 0) {
1732 		hcd = bus_to_hcd(urb->dev->bus);
1733 		retval = unlink1(hcd, urb, status);
1734 		if (retval == 0)
1735 			retval = -EINPROGRESS;
1736 		else if (retval != -EIDRM && retval != -EBUSY)
1737 			dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n",
1738 					urb, retval);
1739 		usb_put_dev(udev);
1740 	}
1741 	return retval;
1742 }
1743 
1744 /*-------------------------------------------------------------------------*/
1745 
1746 static void __usb_hcd_giveback_urb(struct urb *urb)
1747 {
1748 	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1749 	struct usb_anchor *anchor = urb->anchor;
1750 	int status = urb->unlinked;
1751 	unsigned long flags;
1752 
1753 	urb->hcpriv = NULL;
1754 	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1755 	    urb->actual_length < urb->transfer_buffer_length &&
1756 	    !status))
1757 		status = -EREMOTEIO;
1758 
1759 	unmap_urb_for_dma(hcd, urb);
1760 	usbmon_urb_complete(&hcd->self, urb, status);
1761 	usb_anchor_suspend_wakeups(anchor);
1762 	usb_unanchor_urb(urb);
1763 	if (likely(status == 0))
1764 		usb_led_activity(USB_LED_EVENT_HOST);
1765 
1766 	/* pass ownership to the completion handler */
1767 	urb->status = status;
1768 
1769 	/*
1770 	 * We disable local IRQs here avoid possible deadlock because
1771 	 * drivers may call spin_lock() to hold lock which might be
1772 	 * acquired in one hard interrupt handler.
1773 	 *
1774 	 * The local_irq_save()/local_irq_restore() around complete()
1775 	 * will be removed if current USB drivers have been cleaned up
1776 	 * and no one may trigger the above deadlock situation when
1777 	 * running complete() in tasklet.
1778 	 */
1779 	local_irq_save(flags);
1780 	urb->complete(urb);
1781 	local_irq_restore(flags);
1782 
1783 	usb_anchor_resume_wakeups(anchor);
1784 	atomic_dec(&urb->use_count);
1785 	if (unlikely(atomic_read(&urb->reject)))
1786 		wake_up(&usb_kill_urb_queue);
1787 	usb_put_urb(urb);
1788 }
1789 
1790 static void usb_giveback_urb_bh(unsigned long param)
1791 {
1792 	struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param;
1793 	struct list_head local_list;
1794 
1795 	spin_lock_irq(&bh->lock);
1796 	bh->running = true;
1797  restart:
1798 	list_replace_init(&bh->head, &local_list);
1799 	spin_unlock_irq(&bh->lock);
1800 
1801 	while (!list_empty(&local_list)) {
1802 		struct urb *urb;
1803 
1804 		urb = list_entry(local_list.next, struct urb, urb_list);
1805 		list_del_init(&urb->urb_list);
1806 		bh->completing_ep = urb->ep;
1807 		__usb_hcd_giveback_urb(urb);
1808 		bh->completing_ep = NULL;
1809 	}
1810 
1811 	/* check if there are new URBs to giveback */
1812 	spin_lock_irq(&bh->lock);
1813 	if (!list_empty(&bh->head))
1814 		goto restart;
1815 	bh->running = false;
1816 	spin_unlock_irq(&bh->lock);
1817 }
1818 
1819 /**
1820  * usb_hcd_giveback_urb - return URB from HCD to device driver
1821  * @hcd: host controller returning the URB
1822  * @urb: urb being returned to the USB device driver.
1823  * @status: completion status code for the URB.
1824  * Context: in_interrupt()
1825  *
1826  * This hands the URB from HCD to its USB device driver, using its
1827  * completion function.  The HCD has freed all per-urb resources
1828  * (and is done using urb->hcpriv).  It also released all HCD locks;
1829  * the device driver won't cause problems if it frees, modifies,
1830  * or resubmits this URB.
1831  *
1832  * If @urb was unlinked, the value of @status will be overridden by
1833  * @urb->unlinked.  Erroneous short transfers are detected in case
1834  * the HCD hasn't checked for them.
1835  */
1836 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1837 {
1838 	struct giveback_urb_bh *bh;
1839 	bool running, high_prio_bh;
1840 
1841 	/* pass status to tasklet via unlinked */
1842 	if (likely(!urb->unlinked))
1843 		urb->unlinked = status;
1844 
1845 	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1846 		__usb_hcd_giveback_urb(urb);
1847 		return;
1848 	}
1849 
1850 	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
1851 		bh = &hcd->high_prio_bh;
1852 		high_prio_bh = true;
1853 	} else {
1854 		bh = &hcd->low_prio_bh;
1855 		high_prio_bh = false;
1856 	}
1857 
1858 	spin_lock(&bh->lock);
1859 	list_add_tail(&urb->urb_list, &bh->head);
1860 	running = bh->running;
1861 	spin_unlock(&bh->lock);
1862 
1863 	if (running)
1864 		;
1865 	else if (high_prio_bh)
1866 		tasklet_hi_schedule(&bh->bh);
1867 	else
1868 		tasklet_schedule(&bh->bh);
1869 }
1870 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1871 
1872 /*-------------------------------------------------------------------------*/
1873 
1874 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1875  * queue to drain completely.  The caller must first insure that no more
1876  * URBs can be submitted for this endpoint.
1877  */
1878 void usb_hcd_flush_endpoint(struct usb_device *udev,
1879 		struct usb_host_endpoint *ep)
1880 {
1881 	struct usb_hcd		*hcd;
1882 	struct urb		*urb;
1883 
1884 	if (!ep)
1885 		return;
1886 	might_sleep();
1887 	hcd = bus_to_hcd(udev->bus);
1888 
1889 	/* No more submits can occur */
1890 	spin_lock_irq(&hcd_urb_list_lock);
1891 rescan:
1892 	list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) {
1893 		int	is_in;
1894 
1895 		if (urb->unlinked)
1896 			continue;
1897 		usb_get_urb (urb);
1898 		is_in = usb_urb_dir_in(urb);
1899 		spin_unlock(&hcd_urb_list_lock);
1900 
1901 		/* kick hcd */
1902 		unlink1(hcd, urb, -ESHUTDOWN);
1903 		dev_dbg (hcd->self.controller,
1904 			"shutdown urb %pK ep%d%s%s\n",
1905 			urb, usb_endpoint_num(&ep->desc),
1906 			is_in ? "in" : "out",
1907 			({	char *s;
1908 
1909 				 switch (usb_endpoint_type(&ep->desc)) {
1910 				 case USB_ENDPOINT_XFER_CONTROL:
1911 					s = ""; break;
1912 				 case USB_ENDPOINT_XFER_BULK:
1913 					s = "-bulk"; break;
1914 				 case USB_ENDPOINT_XFER_INT:
1915 					s = "-intr"; break;
1916 				 default:
1917 					s = "-iso"; break;
1918 				};
1919 				s;
1920 			}));
1921 		usb_put_urb (urb);
1922 
1923 		/* list contents may have changed */
1924 		spin_lock(&hcd_urb_list_lock);
1925 		goto rescan;
1926 	}
1927 	spin_unlock_irq(&hcd_urb_list_lock);
1928 
1929 	/* Wait until the endpoint queue is completely empty */
1930 	while (!list_empty (&ep->urb_list)) {
1931 		spin_lock_irq(&hcd_urb_list_lock);
1932 
1933 		/* The list may have changed while we acquired the spinlock */
1934 		urb = NULL;
1935 		if (!list_empty (&ep->urb_list)) {
1936 			urb = list_entry (ep->urb_list.prev, struct urb,
1937 					urb_list);
1938 			usb_get_urb (urb);
1939 		}
1940 		spin_unlock_irq(&hcd_urb_list_lock);
1941 
1942 		if (urb) {
1943 			usb_kill_urb (urb);
1944 			usb_put_urb (urb);
1945 		}
1946 	}
1947 }
1948 
1949 /**
1950  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1951  *				the bus bandwidth
1952  * @udev: target &usb_device
1953  * @new_config: new configuration to install
1954  * @cur_alt: the current alternate interface setting
1955  * @new_alt: alternate interface setting that is being installed
1956  *
1957  * To change configurations, pass in the new configuration in new_config,
1958  * and pass NULL for cur_alt and new_alt.
1959  *
1960  * To reset a device's configuration (put the device in the ADDRESSED state),
1961  * pass in NULL for new_config, cur_alt, and new_alt.
1962  *
1963  * To change alternate interface settings, pass in NULL for new_config,
1964  * pass in the current alternate interface setting in cur_alt,
1965  * and pass in the new alternate interface setting in new_alt.
1966  *
1967  * Return: An error if the requested bandwidth change exceeds the
1968  * bus bandwidth or host controller internal resources.
1969  */
1970 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1971 		struct usb_host_config *new_config,
1972 		struct usb_host_interface *cur_alt,
1973 		struct usb_host_interface *new_alt)
1974 {
1975 	int num_intfs, i, j;
1976 	struct usb_host_interface *alt = NULL;
1977 	int ret = 0;
1978 	struct usb_hcd *hcd;
1979 	struct usb_host_endpoint *ep;
1980 
1981 	hcd = bus_to_hcd(udev->bus);
1982 	if (!hcd->driver->check_bandwidth)
1983 		return 0;
1984 
1985 	/* Configuration is being removed - set configuration 0 */
1986 	if (!new_config && !cur_alt) {
1987 		for (i = 1; i < 16; ++i) {
1988 			ep = udev->ep_out[i];
1989 			if (ep)
1990 				hcd->driver->drop_endpoint(hcd, udev, ep);
1991 			ep = udev->ep_in[i];
1992 			if (ep)
1993 				hcd->driver->drop_endpoint(hcd, udev, ep);
1994 		}
1995 		hcd->driver->check_bandwidth(hcd, udev);
1996 		return 0;
1997 	}
1998 	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1999 	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
2000 	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
2001 	 * ok to exclude it.
2002 	 */
2003 	if (new_config) {
2004 		num_intfs = new_config->desc.bNumInterfaces;
2005 		/* Remove endpoints (except endpoint 0, which is always on the
2006 		 * schedule) from the old config from the schedule
2007 		 */
2008 		for (i = 1; i < 16; ++i) {
2009 			ep = udev->ep_out[i];
2010 			if (ep) {
2011 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
2012 				if (ret < 0)
2013 					goto reset;
2014 			}
2015 			ep = udev->ep_in[i];
2016 			if (ep) {
2017 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
2018 				if (ret < 0)
2019 					goto reset;
2020 			}
2021 		}
2022 		for (i = 0; i < num_intfs; ++i) {
2023 			struct usb_host_interface *first_alt;
2024 			int iface_num;
2025 
2026 			first_alt = &new_config->intf_cache[i]->altsetting[0];
2027 			iface_num = first_alt->desc.bInterfaceNumber;
2028 			/* Set up endpoints for alternate interface setting 0 */
2029 			alt = usb_find_alt_setting(new_config, iface_num, 0);
2030 			if (!alt)
2031 				/* No alt setting 0? Pick the first setting. */
2032 				alt = first_alt;
2033 
2034 			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
2035 				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
2036 				if (ret < 0)
2037 					goto reset;
2038 			}
2039 		}
2040 	}
2041 	if (cur_alt && new_alt) {
2042 		struct usb_interface *iface = usb_ifnum_to_if(udev,
2043 				cur_alt->desc.bInterfaceNumber);
2044 
2045 		if (!iface)
2046 			return -EINVAL;
2047 		if (iface->resetting_device) {
2048 			/*
2049 			 * The USB core just reset the device, so the xHCI host
2050 			 * and the device will think alt setting 0 is installed.
2051 			 * However, the USB core will pass in the alternate
2052 			 * setting installed before the reset as cur_alt.  Dig
2053 			 * out the alternate setting 0 structure, or the first
2054 			 * alternate setting if a broken device doesn't have alt
2055 			 * setting 0.
2056 			 */
2057 			cur_alt = usb_altnum_to_altsetting(iface, 0);
2058 			if (!cur_alt)
2059 				cur_alt = &iface->altsetting[0];
2060 		}
2061 
2062 		/* Drop all the endpoints in the current alt setting */
2063 		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
2064 			ret = hcd->driver->drop_endpoint(hcd, udev,
2065 					&cur_alt->endpoint[i]);
2066 			if (ret < 0)
2067 				goto reset;
2068 		}
2069 		/* Add all the endpoints in the new alt setting */
2070 		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
2071 			ret = hcd->driver->add_endpoint(hcd, udev,
2072 					&new_alt->endpoint[i]);
2073 			if (ret < 0)
2074 				goto reset;
2075 		}
2076 	}
2077 	ret = hcd->driver->check_bandwidth(hcd, udev);
2078 reset:
2079 	if (ret < 0)
2080 		hcd->driver->reset_bandwidth(hcd, udev);
2081 	return ret;
2082 }
2083 
2084 /* Disables the endpoint: synchronizes with the hcd to make sure all
2085  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
2086  * have been called previously.  Use for set_configuration, set_interface,
2087  * driver removal, physical disconnect.
2088  *
2089  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
2090  * type, maxpacket size, toggle, halt status, and scheduling.
2091  */
2092 void usb_hcd_disable_endpoint(struct usb_device *udev,
2093 		struct usb_host_endpoint *ep)
2094 {
2095 	struct usb_hcd		*hcd;
2096 
2097 	might_sleep();
2098 	hcd = bus_to_hcd(udev->bus);
2099 	if (hcd->driver->endpoint_disable)
2100 		hcd->driver->endpoint_disable(hcd, ep);
2101 }
2102 
2103 /**
2104  * usb_hcd_reset_endpoint - reset host endpoint state
2105  * @udev: USB device.
2106  * @ep:   the endpoint to reset.
2107  *
2108  * Resets any host endpoint state such as the toggle bit, sequence
2109  * number and current window.
2110  */
2111 void usb_hcd_reset_endpoint(struct usb_device *udev,
2112 			    struct usb_host_endpoint *ep)
2113 {
2114 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2115 
2116 	if (hcd->driver->endpoint_reset)
2117 		hcd->driver->endpoint_reset(hcd, ep);
2118 	else {
2119 		int epnum = usb_endpoint_num(&ep->desc);
2120 		int is_out = usb_endpoint_dir_out(&ep->desc);
2121 		int is_control = usb_endpoint_xfer_control(&ep->desc);
2122 
2123 		usb_settoggle(udev, epnum, is_out, 0);
2124 		if (is_control)
2125 			usb_settoggle(udev, epnum, !is_out, 0);
2126 	}
2127 }
2128 
2129 /**
2130  * usb_alloc_streams - allocate bulk endpoint stream IDs.
2131  * @interface:		alternate setting that includes all endpoints.
2132  * @eps:		array of endpoints that need streams.
2133  * @num_eps:		number of endpoints in the array.
2134  * @num_streams:	number of streams to allocate.
2135  * @mem_flags:		flags hcd should use to allocate memory.
2136  *
2137  * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
2138  * Drivers may queue multiple transfers to different stream IDs, which may
2139  * complete in a different order than they were queued.
2140  *
2141  * Return: On success, the number of allocated streams. On failure, a negative
2142  * error code.
2143  */
2144 int usb_alloc_streams(struct usb_interface *interface,
2145 		struct usb_host_endpoint **eps, unsigned int num_eps,
2146 		unsigned int num_streams, gfp_t mem_flags)
2147 {
2148 	struct usb_hcd *hcd;
2149 	struct usb_device *dev;
2150 	int i, ret;
2151 
2152 	dev = interface_to_usbdev(interface);
2153 	hcd = bus_to_hcd(dev->bus);
2154 	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2155 		return -EINVAL;
2156 	if (dev->speed < USB_SPEED_SUPER)
2157 		return -EINVAL;
2158 	if (dev->state < USB_STATE_CONFIGURED)
2159 		return -ENODEV;
2160 
2161 	for (i = 0; i < num_eps; i++) {
2162 		/* Streams only apply to bulk endpoints. */
2163 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2164 			return -EINVAL;
2165 		/* Re-alloc is not allowed */
2166 		if (eps[i]->streams)
2167 			return -EINVAL;
2168 	}
2169 
2170 	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2171 			num_streams, mem_flags);
2172 	if (ret < 0)
2173 		return ret;
2174 
2175 	for (i = 0; i < num_eps; i++)
2176 		eps[i]->streams = ret;
2177 
2178 	return ret;
2179 }
2180 EXPORT_SYMBOL_GPL(usb_alloc_streams);
2181 
2182 /**
2183  * usb_free_streams - free bulk endpoint stream IDs.
2184  * @interface:	alternate setting that includes all endpoints.
2185  * @eps:	array of endpoints to remove streams from.
2186  * @num_eps:	number of endpoints in the array.
2187  * @mem_flags:	flags hcd should use to allocate memory.
2188  *
2189  * Reverts a group of bulk endpoints back to not using stream IDs.
2190  * Can fail if we are given bad arguments, or HCD is broken.
2191  *
2192  * Return: 0 on success. On failure, a negative error code.
2193  */
2194 int usb_free_streams(struct usb_interface *interface,
2195 		struct usb_host_endpoint **eps, unsigned int num_eps,
2196 		gfp_t mem_flags)
2197 {
2198 	struct usb_hcd *hcd;
2199 	struct usb_device *dev;
2200 	int i, ret;
2201 
2202 	dev = interface_to_usbdev(interface);
2203 	hcd = bus_to_hcd(dev->bus);
2204 	if (dev->speed < USB_SPEED_SUPER)
2205 		return -EINVAL;
2206 
2207 	/* Double-free is not allowed */
2208 	for (i = 0; i < num_eps; i++)
2209 		if (!eps[i] || !eps[i]->streams)
2210 			return -EINVAL;
2211 
2212 	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2213 	if (ret < 0)
2214 		return ret;
2215 
2216 	for (i = 0; i < num_eps; i++)
2217 		eps[i]->streams = 0;
2218 
2219 	return ret;
2220 }
2221 EXPORT_SYMBOL_GPL(usb_free_streams);
2222 
2223 /* Protect against drivers that try to unlink URBs after the device
2224  * is gone, by waiting until all unlinks for @udev are finished.
2225  * Since we don't currently track URBs by device, simply wait until
2226  * nothing is running in the locked region of usb_hcd_unlink_urb().
2227  */
2228 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2229 {
2230 	spin_lock_irq(&hcd_urb_unlink_lock);
2231 	spin_unlock_irq(&hcd_urb_unlink_lock);
2232 }
2233 
2234 /*-------------------------------------------------------------------------*/
2235 
2236 /* called in any context */
2237 int usb_hcd_get_frame_number (struct usb_device *udev)
2238 {
2239 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
2240 
2241 	if (!HCD_RH_RUNNING(hcd))
2242 		return -ESHUTDOWN;
2243 	return hcd->driver->get_frame_number (hcd);
2244 }
2245 
2246 /*-------------------------------------------------------------------------*/
2247 
2248 #ifdef	CONFIG_PM
2249 
2250 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2251 {
2252 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2253 	int		status;
2254 	int		old_state = hcd->state;
2255 
2256 	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2257 			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2258 			rhdev->do_remote_wakeup);
2259 	if (HCD_DEAD(hcd)) {
2260 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2261 		return 0;
2262 	}
2263 
2264 	if (!hcd->driver->bus_suspend) {
2265 		status = -ENOENT;
2266 	} else {
2267 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2268 		hcd->state = HC_STATE_QUIESCING;
2269 		status = hcd->driver->bus_suspend(hcd);
2270 	}
2271 	if (status == 0) {
2272 		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2273 		hcd->state = HC_STATE_SUSPENDED;
2274 
2275 		/* Did we race with a root-hub wakeup event? */
2276 		if (rhdev->do_remote_wakeup) {
2277 			char	buffer[6];
2278 
2279 			status = hcd->driver->hub_status_data(hcd, buffer);
2280 			if (status != 0) {
2281 				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2282 				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2283 				status = -EBUSY;
2284 			}
2285 		}
2286 	} else {
2287 		spin_lock_irq(&hcd_root_hub_lock);
2288 		if (!HCD_DEAD(hcd)) {
2289 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2290 			hcd->state = old_state;
2291 		}
2292 		spin_unlock_irq(&hcd_root_hub_lock);
2293 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2294 				"suspend", status);
2295 	}
2296 	return status;
2297 }
2298 
2299 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2300 {
2301 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2302 	int		status;
2303 	int		old_state = hcd->state;
2304 
2305 	dev_dbg(&rhdev->dev, "usb %sresume\n",
2306 			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2307 	if (HCD_DEAD(hcd)) {
2308 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2309 		return 0;
2310 	}
2311 	if (!hcd->driver->bus_resume)
2312 		return -ENOENT;
2313 	if (HCD_RH_RUNNING(hcd))
2314 		return 0;
2315 
2316 	hcd->state = HC_STATE_RESUMING;
2317 	status = hcd->driver->bus_resume(hcd);
2318 	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2319 	if (status == 0) {
2320 		struct usb_device *udev;
2321 		int port1;
2322 
2323 		spin_lock_irq(&hcd_root_hub_lock);
2324 		if (!HCD_DEAD(hcd)) {
2325 			usb_set_device_state(rhdev, rhdev->actconfig
2326 					? USB_STATE_CONFIGURED
2327 					: USB_STATE_ADDRESS);
2328 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2329 			hcd->state = HC_STATE_RUNNING;
2330 		}
2331 		spin_unlock_irq(&hcd_root_hub_lock);
2332 
2333 		/*
2334 		 * Check whether any of the enabled ports on the root hub are
2335 		 * unsuspended.  If they are then a TRSMRCY delay is needed
2336 		 * (this is what the USB-2 spec calls a "global resume").
2337 		 * Otherwise we can skip the delay.
2338 		 */
2339 		usb_hub_for_each_child(rhdev, port1, udev) {
2340 			if (udev->state != USB_STATE_NOTATTACHED &&
2341 					!udev->port_is_suspended) {
2342 				usleep_range(10000, 11000);	/* TRSMRCY */
2343 				break;
2344 			}
2345 		}
2346 	} else {
2347 		hcd->state = old_state;
2348 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2349 				"resume", status);
2350 		if (status != -ESHUTDOWN)
2351 			usb_hc_died(hcd);
2352 	}
2353 	return status;
2354 }
2355 
2356 /* Workqueue routine for root-hub remote wakeup */
2357 static void hcd_resume_work(struct work_struct *work)
2358 {
2359 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2360 	struct usb_device *udev = hcd->self.root_hub;
2361 
2362 	usb_remote_wakeup(udev);
2363 }
2364 
2365 /**
2366  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2367  * @hcd: host controller for this root hub
2368  *
2369  * The USB host controller calls this function when its root hub is
2370  * suspended (with the remote wakeup feature enabled) and a remote
2371  * wakeup request is received.  The routine submits a workqueue request
2372  * to resume the root hub (that is, manage its downstream ports again).
2373  */
2374 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2375 {
2376 	unsigned long flags;
2377 
2378 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2379 	if (hcd->rh_registered) {
2380 		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2381 		queue_work(pm_wq, &hcd->wakeup_work);
2382 	}
2383 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2384 }
2385 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2386 
2387 #endif	/* CONFIG_PM */
2388 
2389 /*-------------------------------------------------------------------------*/
2390 
2391 #ifdef	CONFIG_USB_OTG
2392 
2393 /**
2394  * usb_bus_start_enum - start immediate enumeration (for OTG)
2395  * @bus: the bus (must use hcd framework)
2396  * @port_num: 1-based number of port; usually bus->otg_port
2397  * Context: in_interrupt()
2398  *
2399  * Starts enumeration, with an immediate reset followed later by
2400  * hub_wq identifying and possibly configuring the device.
2401  * This is needed by OTG controller drivers, where it helps meet
2402  * HNP protocol timing requirements for starting a port reset.
2403  *
2404  * Return: 0 if successful.
2405  */
2406 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2407 {
2408 	struct usb_hcd		*hcd;
2409 	int			status = -EOPNOTSUPP;
2410 
2411 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2412 	 * boards with root hubs hooked up to internal devices (instead of
2413 	 * just the OTG port) may need more attention to resetting...
2414 	 */
2415 	hcd = bus_to_hcd(bus);
2416 	if (port_num && hcd->driver->start_port_reset)
2417 		status = hcd->driver->start_port_reset(hcd, port_num);
2418 
2419 	/* allocate hub_wq shortly after (first) root port reset finishes;
2420 	 * it may issue others, until at least 50 msecs have passed.
2421 	 */
2422 	if (status == 0)
2423 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2424 	return status;
2425 }
2426 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2427 
2428 #endif
2429 
2430 /*-------------------------------------------------------------------------*/
2431 
2432 /**
2433  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2434  * @irq: the IRQ being raised
2435  * @__hcd: pointer to the HCD whose IRQ is being signaled
2436  *
2437  * If the controller isn't HALTed, calls the driver's irq handler.
2438  * Checks whether the controller is now dead.
2439  *
2440  * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2441  */
2442 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2443 {
2444 	struct usb_hcd		*hcd = __hcd;
2445 	irqreturn_t		rc;
2446 
2447 	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2448 		rc = IRQ_NONE;
2449 	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2450 		rc = IRQ_NONE;
2451 	else
2452 		rc = IRQ_HANDLED;
2453 
2454 	return rc;
2455 }
2456 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2457 
2458 /*-------------------------------------------------------------------------*/
2459 
2460 /**
2461  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2462  * @hcd: pointer to the HCD representing the controller
2463  *
2464  * This is called by bus glue to report a USB host controller that died
2465  * while operations may still have been pending.  It's called automatically
2466  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2467  *
2468  * Only call this function with the primary HCD.
2469  */
2470 void usb_hc_died (struct usb_hcd *hcd)
2471 {
2472 	unsigned long flags;
2473 
2474 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2475 
2476 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2477 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2478 	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2479 	if (hcd->rh_registered) {
2480 		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2481 
2482 		/* make hub_wq clean up old urbs and devices */
2483 		usb_set_device_state (hcd->self.root_hub,
2484 				USB_STATE_NOTATTACHED);
2485 		usb_kick_hub_wq(hcd->self.root_hub);
2486 	}
2487 	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2488 		hcd = hcd->shared_hcd;
2489 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2490 		set_bit(HCD_FLAG_DEAD, &hcd->flags);
2491 		if (hcd->rh_registered) {
2492 			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2493 
2494 			/* make hub_wq clean up old urbs and devices */
2495 			usb_set_device_state(hcd->self.root_hub,
2496 					USB_STATE_NOTATTACHED);
2497 			usb_kick_hub_wq(hcd->self.root_hub);
2498 		}
2499 	}
2500 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2501 	/* Make sure that the other roothub is also deallocated. */
2502 }
2503 EXPORT_SYMBOL_GPL (usb_hc_died);
2504 
2505 /*-------------------------------------------------------------------------*/
2506 
2507 static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2508 {
2509 
2510 	spin_lock_init(&bh->lock);
2511 	INIT_LIST_HEAD(&bh->head);
2512 	tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh);
2513 }
2514 
2515 struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
2516 		struct device *sysdev, struct device *dev, const char *bus_name,
2517 		struct usb_hcd *primary_hcd)
2518 {
2519 	struct usb_hcd *hcd;
2520 
2521 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2522 	if (!hcd)
2523 		return NULL;
2524 	if (primary_hcd == NULL) {
2525 		hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex),
2526 				GFP_KERNEL);
2527 		if (!hcd->address0_mutex) {
2528 			kfree(hcd);
2529 			dev_dbg(dev, "hcd address0 mutex alloc failed\n");
2530 			return NULL;
2531 		}
2532 		mutex_init(hcd->address0_mutex);
2533 		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2534 				GFP_KERNEL);
2535 		if (!hcd->bandwidth_mutex) {
2536 			kfree(hcd->address0_mutex);
2537 			kfree(hcd);
2538 			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2539 			return NULL;
2540 		}
2541 		mutex_init(hcd->bandwidth_mutex);
2542 		dev_set_drvdata(dev, hcd);
2543 	} else {
2544 		mutex_lock(&usb_port_peer_mutex);
2545 		hcd->address0_mutex = primary_hcd->address0_mutex;
2546 		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2547 		hcd->primary_hcd = primary_hcd;
2548 		primary_hcd->primary_hcd = primary_hcd;
2549 		hcd->shared_hcd = primary_hcd;
2550 		primary_hcd->shared_hcd = hcd;
2551 		mutex_unlock(&usb_port_peer_mutex);
2552 	}
2553 
2554 	kref_init(&hcd->kref);
2555 
2556 	usb_bus_init(&hcd->self);
2557 	hcd->self.controller = dev;
2558 	hcd->self.sysdev = sysdev;
2559 	hcd->self.bus_name = bus_name;
2560 	hcd->self.uses_dma = (sysdev->dma_mask != NULL);
2561 
2562 	setup_timer(&hcd->rh_timer, rh_timer_func, (unsigned long)hcd);
2563 #ifdef CONFIG_PM
2564 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2565 #endif
2566 
2567 	hcd->driver = driver;
2568 	hcd->speed = driver->flags & HCD_MASK;
2569 	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2570 			"USB Host Controller";
2571 	return hcd;
2572 }
2573 EXPORT_SYMBOL_GPL(__usb_create_hcd);
2574 
2575 /**
2576  * usb_create_shared_hcd - create and initialize an HCD structure
2577  * @driver: HC driver that will use this hcd
2578  * @dev: device for this HC, stored in hcd->self.controller
2579  * @bus_name: value to store in hcd->self.bus_name
2580  * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2581  *              PCI device.  Only allocate certain resources for the primary HCD
2582  * Context: !in_interrupt()
2583  *
2584  * Allocate a struct usb_hcd, with extra space at the end for the
2585  * HC driver's private data.  Initialize the generic members of the
2586  * hcd structure.
2587  *
2588  * Return: On success, a pointer to the created and initialized HCD structure.
2589  * On failure (e.g. if memory is unavailable), %NULL.
2590  */
2591 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2592 		struct device *dev, const char *bus_name,
2593 		struct usb_hcd *primary_hcd)
2594 {
2595 	return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd);
2596 }
2597 EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2598 
2599 /**
2600  * usb_create_hcd - create and initialize an HCD structure
2601  * @driver: HC driver that will use this hcd
2602  * @dev: device for this HC, stored in hcd->self.controller
2603  * @bus_name: value to store in hcd->self.bus_name
2604  * Context: !in_interrupt()
2605  *
2606  * Allocate a struct usb_hcd, with extra space at the end for the
2607  * HC driver's private data.  Initialize the generic members of the
2608  * hcd structure.
2609  *
2610  * Return: On success, a pointer to the created and initialized HCD
2611  * structure. On failure (e.g. if memory is unavailable), %NULL.
2612  */
2613 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2614 		struct device *dev, const char *bus_name)
2615 {
2616 	return __usb_create_hcd(driver, dev, dev, bus_name, NULL);
2617 }
2618 EXPORT_SYMBOL_GPL(usb_create_hcd);
2619 
2620 /*
2621  * Roothubs that share one PCI device must also share the bandwidth mutex.
2622  * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2623  * deallocated.
2624  *
2625  * Make sure to deallocate the bandwidth_mutex only when the last HCD is
2626  * freed.  When hcd_release() is called for either hcd in a peer set,
2627  * invalidate the peer's ->shared_hcd and ->primary_hcd pointers.
2628  */
2629 static void hcd_release(struct kref *kref)
2630 {
2631 	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2632 
2633 	mutex_lock(&usb_port_peer_mutex);
2634 	if (hcd->shared_hcd) {
2635 		struct usb_hcd *peer = hcd->shared_hcd;
2636 
2637 		peer->shared_hcd = NULL;
2638 		peer->primary_hcd = NULL;
2639 	} else {
2640 		kfree(hcd->address0_mutex);
2641 		kfree(hcd->bandwidth_mutex);
2642 	}
2643 	mutex_unlock(&usb_port_peer_mutex);
2644 	kfree(hcd);
2645 }
2646 
2647 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2648 {
2649 	if (hcd)
2650 		kref_get (&hcd->kref);
2651 	return hcd;
2652 }
2653 EXPORT_SYMBOL_GPL(usb_get_hcd);
2654 
2655 void usb_put_hcd (struct usb_hcd *hcd)
2656 {
2657 	if (hcd)
2658 		kref_put (&hcd->kref, hcd_release);
2659 }
2660 EXPORT_SYMBOL_GPL(usb_put_hcd);
2661 
2662 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2663 {
2664 	if (!hcd->primary_hcd)
2665 		return 1;
2666 	return hcd == hcd->primary_hcd;
2667 }
2668 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2669 
2670 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2671 {
2672 	if (!hcd->driver->find_raw_port_number)
2673 		return port1;
2674 
2675 	return hcd->driver->find_raw_port_number(hcd, port1);
2676 }
2677 
2678 static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2679 		unsigned int irqnum, unsigned long irqflags)
2680 {
2681 	int retval;
2682 
2683 	if (hcd->driver->irq) {
2684 
2685 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2686 				hcd->driver->description, hcd->self.busnum);
2687 		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2688 				hcd->irq_descr, hcd);
2689 		if (retval != 0) {
2690 			dev_err(hcd->self.controller,
2691 					"request interrupt %d failed\n",
2692 					irqnum);
2693 			return retval;
2694 		}
2695 		hcd->irq = irqnum;
2696 		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2697 				(hcd->driver->flags & HCD_MEMORY) ?
2698 					"io mem" : "io base",
2699 					(unsigned long long)hcd->rsrc_start);
2700 	} else {
2701 		hcd->irq = 0;
2702 		if (hcd->rsrc_start)
2703 			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2704 					(hcd->driver->flags & HCD_MEMORY) ?
2705 					"io mem" : "io base",
2706 					(unsigned long long)hcd->rsrc_start);
2707 	}
2708 	return 0;
2709 }
2710 
2711 /*
2712  * Before we free this root hub, flush in-flight peering attempts
2713  * and disable peer lookups
2714  */
2715 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2716 {
2717 	struct usb_device *rhdev;
2718 
2719 	mutex_lock(&usb_port_peer_mutex);
2720 	rhdev = hcd->self.root_hub;
2721 	hcd->self.root_hub = NULL;
2722 	mutex_unlock(&usb_port_peer_mutex);
2723 	usb_put_dev(rhdev);
2724 }
2725 
2726 /**
2727  * usb_add_hcd - finish generic HCD structure initialization and register
2728  * @hcd: the usb_hcd structure to initialize
2729  * @irqnum: Interrupt line to allocate
2730  * @irqflags: Interrupt type flags
2731  *
2732  * Finish the remaining parts of generic HCD initialization: allocate the
2733  * buffers of consistent memory, register the bus, request the IRQ line,
2734  * and call the driver's reset() and start() routines.
2735  */
2736 int usb_add_hcd(struct usb_hcd *hcd,
2737 		unsigned int irqnum, unsigned long irqflags)
2738 {
2739 	int retval;
2740 	struct usb_device *rhdev;
2741 
2742 	if (IS_ENABLED(CONFIG_USB_PHY) && !hcd->usb_phy) {
2743 		struct usb_phy *phy = usb_get_phy_dev(hcd->self.sysdev, 0);
2744 
2745 		if (IS_ERR(phy)) {
2746 			retval = PTR_ERR(phy);
2747 			if (retval == -EPROBE_DEFER)
2748 				return retval;
2749 		} else {
2750 			retval = usb_phy_init(phy);
2751 			if (retval) {
2752 				usb_put_phy(phy);
2753 				return retval;
2754 			}
2755 			hcd->usb_phy = phy;
2756 			hcd->remove_phy = 1;
2757 		}
2758 	}
2759 
2760 	if (IS_ENABLED(CONFIG_GENERIC_PHY) && !hcd->phy) {
2761 		struct phy *phy = phy_get(hcd->self.sysdev, "usb");
2762 
2763 		if (IS_ERR(phy)) {
2764 			retval = PTR_ERR(phy);
2765 			if (retval == -EPROBE_DEFER)
2766 				goto err_phy;
2767 		} else {
2768 			retval = phy_init(phy);
2769 			if (retval) {
2770 				phy_put(phy);
2771 				goto err_phy;
2772 			}
2773 			retval = phy_power_on(phy);
2774 			if (retval) {
2775 				phy_exit(phy);
2776 				phy_put(phy);
2777 				goto err_phy;
2778 			}
2779 			hcd->phy = phy;
2780 			hcd->remove_phy = 1;
2781 		}
2782 	}
2783 
2784 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2785 
2786 	/* Keep old behaviour if authorized_default is not in [0, 1]. */
2787 	if (authorized_default < 0 || authorized_default > 1) {
2788 		if (hcd->wireless)
2789 			clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2790 		else
2791 			set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2792 	} else {
2793 		if (authorized_default)
2794 			set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2795 		else
2796 			clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2797 	}
2798 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2799 
2800 	/* per default all interfaces are authorized */
2801 	set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
2802 
2803 	/* HC is in reset state, but accessible.  Now do the one-time init,
2804 	 * bottom up so that hcds can customize the root hubs before hub_wq
2805 	 * starts talking to them.  (Note, bus id is assigned early too.)
2806 	 */
2807 	retval = hcd_buffer_create(hcd);
2808 	if (retval != 0) {
2809 		dev_dbg(hcd->self.sysdev, "pool alloc failed\n");
2810 		goto err_create_buf;
2811 	}
2812 
2813 	retval = usb_register_bus(&hcd->self);
2814 	if (retval < 0)
2815 		goto err_register_bus;
2816 
2817 	rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2818 	if (rhdev == NULL) {
2819 		dev_err(hcd->self.sysdev, "unable to allocate root hub\n");
2820 		retval = -ENOMEM;
2821 		goto err_allocate_root_hub;
2822 	}
2823 	mutex_lock(&usb_port_peer_mutex);
2824 	hcd->self.root_hub = rhdev;
2825 	mutex_unlock(&usb_port_peer_mutex);
2826 
2827 	switch (hcd->speed) {
2828 	case HCD_USB11:
2829 		rhdev->speed = USB_SPEED_FULL;
2830 		break;
2831 	case HCD_USB2:
2832 		rhdev->speed = USB_SPEED_HIGH;
2833 		break;
2834 	case HCD_USB25:
2835 		rhdev->speed = USB_SPEED_WIRELESS;
2836 		break;
2837 	case HCD_USB3:
2838 		rhdev->speed = USB_SPEED_SUPER;
2839 		break;
2840 	case HCD_USB31:
2841 		rhdev->speed = USB_SPEED_SUPER_PLUS;
2842 		break;
2843 	default:
2844 		retval = -EINVAL;
2845 		goto err_set_rh_speed;
2846 	}
2847 
2848 	/* wakeup flag init defaults to "everything works" for root hubs,
2849 	 * but drivers can override it in reset() if needed, along with
2850 	 * recording the overall controller's system wakeup capability.
2851 	 */
2852 	device_set_wakeup_capable(&rhdev->dev, 1);
2853 
2854 	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2855 	 * registered.  But since the controller can die at any time,
2856 	 * let's initialize the flag before touching the hardware.
2857 	 */
2858 	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2859 
2860 	/* "reset" is misnamed; its role is now one-time init. the controller
2861 	 * should already have been reset (and boot firmware kicked off etc).
2862 	 */
2863 	if (hcd->driver->reset) {
2864 		retval = hcd->driver->reset(hcd);
2865 		if (retval < 0) {
2866 			dev_err(hcd->self.controller, "can't setup: %d\n",
2867 					retval);
2868 			goto err_hcd_driver_setup;
2869 		}
2870 	}
2871 	hcd->rh_pollable = 1;
2872 
2873 	/* NOTE: root hub and controller capabilities may not be the same */
2874 	if (device_can_wakeup(hcd->self.controller)
2875 			&& device_can_wakeup(&hcd->self.root_hub->dev))
2876 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2877 
2878 	/* initialize tasklets */
2879 	init_giveback_urb_bh(&hcd->high_prio_bh);
2880 	init_giveback_urb_bh(&hcd->low_prio_bh);
2881 
2882 	/* enable irqs just before we start the controller,
2883 	 * if the BIOS provides legacy PCI irqs.
2884 	 */
2885 	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2886 		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2887 		if (retval)
2888 			goto err_request_irq;
2889 	}
2890 
2891 	hcd->state = HC_STATE_RUNNING;
2892 	retval = hcd->driver->start(hcd);
2893 	if (retval < 0) {
2894 		dev_err(hcd->self.controller, "startup error %d\n", retval);
2895 		goto err_hcd_driver_start;
2896 	}
2897 
2898 	/* starting here, usbcore will pay attention to this root hub */
2899 	retval = register_root_hub(hcd);
2900 	if (retval != 0)
2901 		goto err_register_root_hub;
2902 
2903 	retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2904 	if (retval < 0) {
2905 		printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n",
2906 		       retval);
2907 		goto error_create_attr_group;
2908 	}
2909 	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2910 		usb_hcd_poll_rh_status(hcd);
2911 
2912 	return retval;
2913 
2914 error_create_attr_group:
2915 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2916 	if (HC_IS_RUNNING(hcd->state))
2917 		hcd->state = HC_STATE_QUIESCING;
2918 	spin_lock_irq(&hcd_root_hub_lock);
2919 	hcd->rh_registered = 0;
2920 	spin_unlock_irq(&hcd_root_hub_lock);
2921 
2922 #ifdef CONFIG_PM
2923 	cancel_work_sync(&hcd->wakeup_work);
2924 #endif
2925 	mutex_lock(&usb_bus_idr_lock);
2926 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2927 	mutex_unlock(&usb_bus_idr_lock);
2928 err_register_root_hub:
2929 	hcd->rh_pollable = 0;
2930 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2931 	del_timer_sync(&hcd->rh_timer);
2932 	hcd->driver->stop(hcd);
2933 	hcd->state = HC_STATE_HALT;
2934 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2935 	del_timer_sync(&hcd->rh_timer);
2936 err_hcd_driver_start:
2937 	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2938 		free_irq(irqnum, hcd);
2939 err_request_irq:
2940 err_hcd_driver_setup:
2941 err_set_rh_speed:
2942 	usb_put_invalidate_rhdev(hcd);
2943 err_allocate_root_hub:
2944 	usb_deregister_bus(&hcd->self);
2945 err_register_bus:
2946 	hcd_buffer_destroy(hcd);
2947 err_create_buf:
2948 	if (IS_ENABLED(CONFIG_GENERIC_PHY) && hcd->remove_phy && hcd->phy) {
2949 		phy_power_off(hcd->phy);
2950 		phy_exit(hcd->phy);
2951 		phy_put(hcd->phy);
2952 		hcd->phy = NULL;
2953 	}
2954 err_phy:
2955 	if (hcd->remove_phy && hcd->usb_phy) {
2956 		usb_phy_shutdown(hcd->usb_phy);
2957 		usb_put_phy(hcd->usb_phy);
2958 		hcd->usb_phy = NULL;
2959 	}
2960 	return retval;
2961 }
2962 EXPORT_SYMBOL_GPL(usb_add_hcd);
2963 
2964 /**
2965  * usb_remove_hcd - shutdown processing for generic HCDs
2966  * @hcd: the usb_hcd structure to remove
2967  * Context: !in_interrupt()
2968  *
2969  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2970  * invoking the HCD's stop() method.
2971  */
2972 void usb_remove_hcd(struct usb_hcd *hcd)
2973 {
2974 	struct usb_device *rhdev = hcd->self.root_hub;
2975 
2976 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2977 
2978 	usb_get_dev(rhdev);
2979 	sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2980 
2981 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2982 	if (HC_IS_RUNNING (hcd->state))
2983 		hcd->state = HC_STATE_QUIESCING;
2984 
2985 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2986 	spin_lock_irq (&hcd_root_hub_lock);
2987 	hcd->rh_registered = 0;
2988 	spin_unlock_irq (&hcd_root_hub_lock);
2989 
2990 #ifdef CONFIG_PM
2991 	cancel_work_sync(&hcd->wakeup_work);
2992 #endif
2993 
2994 	mutex_lock(&usb_bus_idr_lock);
2995 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2996 	mutex_unlock(&usb_bus_idr_lock);
2997 
2998 	/*
2999 	 * tasklet_kill() isn't needed here because:
3000 	 * - driver's disconnect() called from usb_disconnect() should
3001 	 *   make sure its URBs are completed during the disconnect()
3002 	 *   callback
3003 	 *
3004 	 * - it is too late to run complete() here since driver may have
3005 	 *   been removed already now
3006 	 */
3007 
3008 	/* Prevent any more root-hub status calls from the timer.
3009 	 * The HCD might still restart the timer (if a port status change
3010 	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
3011 	 * the hub_status_data() callback.
3012 	 */
3013 	hcd->rh_pollable = 0;
3014 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
3015 	del_timer_sync(&hcd->rh_timer);
3016 
3017 	hcd->driver->stop(hcd);
3018 	hcd->state = HC_STATE_HALT;
3019 
3020 	/* In case the HCD restarted the timer, stop it again. */
3021 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
3022 	del_timer_sync(&hcd->rh_timer);
3023 
3024 	if (usb_hcd_is_primary_hcd(hcd)) {
3025 		if (hcd->irq > 0)
3026 			free_irq(hcd->irq, hcd);
3027 	}
3028 
3029 	usb_deregister_bus(&hcd->self);
3030 	hcd_buffer_destroy(hcd);
3031 
3032 	if (IS_ENABLED(CONFIG_GENERIC_PHY) && hcd->remove_phy && hcd->phy) {
3033 		phy_power_off(hcd->phy);
3034 		phy_exit(hcd->phy);
3035 		phy_put(hcd->phy);
3036 		hcd->phy = NULL;
3037 	}
3038 	if (hcd->remove_phy && hcd->usb_phy) {
3039 		usb_phy_shutdown(hcd->usb_phy);
3040 		usb_put_phy(hcd->usb_phy);
3041 		hcd->usb_phy = NULL;
3042 	}
3043 
3044 	usb_put_invalidate_rhdev(hcd);
3045 	hcd->flags = 0;
3046 }
3047 EXPORT_SYMBOL_GPL(usb_remove_hcd);
3048 
3049 void
3050 usb_hcd_platform_shutdown(struct platform_device *dev)
3051 {
3052 	struct usb_hcd *hcd = platform_get_drvdata(dev);
3053 
3054 	if (hcd->driver->shutdown)
3055 		hcd->driver->shutdown(hcd);
3056 }
3057 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
3058 
3059 /*-------------------------------------------------------------------------*/
3060 
3061 #if IS_ENABLED(CONFIG_USB_MON)
3062 
3063 const struct usb_mon_operations *mon_ops;
3064 
3065 /*
3066  * The registration is unlocked.
3067  * We do it this way because we do not want to lock in hot paths.
3068  *
3069  * Notice that the code is minimally error-proof. Because usbmon needs
3070  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
3071  */
3072 
3073 int usb_mon_register(const struct usb_mon_operations *ops)
3074 {
3075 
3076 	if (mon_ops)
3077 		return -EBUSY;
3078 
3079 	mon_ops = ops;
3080 	mb();
3081 	return 0;
3082 }
3083 EXPORT_SYMBOL_GPL (usb_mon_register);
3084 
3085 void usb_mon_deregister (void)
3086 {
3087 
3088 	if (mon_ops == NULL) {
3089 		printk(KERN_ERR "USB: monitor was not registered\n");
3090 		return;
3091 	}
3092 	mon_ops = NULL;
3093 	mb();
3094 }
3095 EXPORT_SYMBOL_GPL (usb_mon_deregister);
3096 
3097 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
3098