xref: /openbmc/linux/drivers/usb/core/hcd.c (revision 9b93eb47)
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 
12 #include <linux/bcd.h>
13 #include <linux/module.h>
14 #include <linux/version.h>
15 #include <linux/kernel.h>
16 #include <linux/sched/task_stack.h>
17 #include <linux/slab.h>
18 #include <linux/completion.h>
19 #include <linux/utsname.h>
20 #include <linux/mm.h>
21 #include <asm/io.h>
22 #include <linux/device.h>
23 #include <linux/dma-mapping.h>
24 #include <linux/mutex.h>
25 #include <asm/irq.h>
26 #include <asm/byteorder.h>
27 #include <asm/unaligned.h>
28 #include <linux/platform_device.h>
29 #include <linux/workqueue.h>
30 #include <linux/pm_runtime.h>
31 #include <linux/types.h>
32 
33 #include <linux/phy/phy.h>
34 #include <linux/usb.h>
35 #include <linux/usb/hcd.h>
36 #include <linux/usb/otg.h>
37 
38 #include "usb.h"
39 #include "phy.h"
40 
41 
42 /*-------------------------------------------------------------------------*/
43 
44 /*
45  * USB Host Controller Driver framework
46  *
47  * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
48  * HCD-specific behaviors/bugs.
49  *
50  * This does error checks, tracks devices and urbs, and delegates to a
51  * "hc_driver" only for code (and data) that really needs to know about
52  * hardware differences.  That includes root hub registers, i/o queues,
53  * and so on ... but as little else as possible.
54  *
55  * Shared code includes most of the "root hub" code (these are emulated,
56  * though each HC's hardware works differently) and PCI glue, plus request
57  * tracking overhead.  The HCD code should only block on spinlocks or on
58  * hardware handshaking; blocking on software events (such as other kernel
59  * threads releasing resources, or completing actions) is all generic.
60  *
61  * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
62  * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
63  * only by the hub driver ... and that neither should be seen or used by
64  * usb client device drivers.
65  *
66  * Contributors of ideas or unattributed patches include: David Brownell,
67  * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
68  *
69  * HISTORY:
70  * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
71  *		associated cleanup.  "usb_hcd" still != "usb_bus".
72  * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
73  */
74 
75 /*-------------------------------------------------------------------------*/
76 
77 /* Keep track of which host controller drivers are loaded */
78 unsigned long usb_hcds_loaded;
79 EXPORT_SYMBOL_GPL(usb_hcds_loaded);
80 
81 /* host controllers we manage */
82 DEFINE_IDR (usb_bus_idr);
83 EXPORT_SYMBOL_GPL (usb_bus_idr);
84 
85 /* used when allocating bus numbers */
86 #define USB_MAXBUS		64
87 
88 /* used when updating list of hcds */
89 DEFINE_MUTEX(usb_bus_idr_lock);	/* exported only for usbfs */
90 EXPORT_SYMBOL_GPL (usb_bus_idr_lock);
91 
92 /* used for controlling access to virtual root hubs */
93 static DEFINE_SPINLOCK(hcd_root_hub_lock);
94 
95 /* used when updating an endpoint's URB list */
96 static DEFINE_SPINLOCK(hcd_urb_list_lock);
97 
98 /* used to protect against unlinking URBs after the device is gone */
99 static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
100 
101 /* wait queue for synchronous unlinks */
102 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
103 
104 static inline int is_root_hub(struct usb_device *udev)
105 {
106 	return (udev->parent == NULL);
107 }
108 
109 /*-------------------------------------------------------------------------*/
110 
111 /*
112  * Sharable chunks of root hub code.
113  */
114 
115 /*-------------------------------------------------------------------------*/
116 #define KERNEL_REL	bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff))
117 #define KERNEL_VER	bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff))
118 
119 /* usb 3.1 root hub device descriptor */
120 static const u8 usb31_rh_dev_descriptor[18] = {
121 	0x12,       /*  __u8  bLength; */
122 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
123 	0x10, 0x03, /*  __le16 bcdUSB; v3.1 */
124 
125 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
126 	0x00,	    /*  __u8  bDeviceSubClass; */
127 	0x03,       /*  __u8  bDeviceProtocol; USB 3 hub */
128 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
129 
130 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
131 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
132 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
133 
134 	0x03,       /*  __u8  iManufacturer; */
135 	0x02,       /*  __u8  iProduct; */
136 	0x01,       /*  __u8  iSerialNumber; */
137 	0x01        /*  __u8  bNumConfigurations; */
138 };
139 
140 /* usb 3.0 root hub device descriptor */
141 static const u8 usb3_rh_dev_descriptor[18] = {
142 	0x12,       /*  __u8  bLength; */
143 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
144 	0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
145 
146 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
147 	0x00,	    /*  __u8  bDeviceSubClass; */
148 	0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
149 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
150 
151 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
152 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
153 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
154 
155 	0x03,       /*  __u8  iManufacturer; */
156 	0x02,       /*  __u8  iProduct; */
157 	0x01,       /*  __u8  iSerialNumber; */
158 	0x01        /*  __u8  bNumConfigurations; */
159 };
160 
161 /* usb 2.5 (wireless USB 1.0) root hub device descriptor */
162 static const u8 usb25_rh_dev_descriptor[18] = {
163 	0x12,       /*  __u8  bLength; */
164 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
165 	0x50, 0x02, /*  __le16 bcdUSB; v2.5 */
166 
167 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
168 	0x00,	    /*  __u8  bDeviceSubClass; */
169 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
170 	0xFF,       /*  __u8  bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */
171 
172 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
173 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
174 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
175 
176 	0x03,       /*  __u8  iManufacturer; */
177 	0x02,       /*  __u8  iProduct; */
178 	0x01,       /*  __u8  iSerialNumber; */
179 	0x01        /*  __u8  bNumConfigurations; */
180 };
181 
182 /* usb 2.0 root hub device descriptor */
183 static const u8 usb2_rh_dev_descriptor[18] = {
184 	0x12,       /*  __u8  bLength; */
185 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
186 	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
187 
188 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
189 	0x00,	    /*  __u8  bDeviceSubClass; */
190 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
191 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
192 
193 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
194 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
195 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
196 
197 	0x03,       /*  __u8  iManufacturer; */
198 	0x02,       /*  __u8  iProduct; */
199 	0x01,       /*  __u8  iSerialNumber; */
200 	0x01        /*  __u8  bNumConfigurations; */
201 };
202 
203 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
204 
205 /* usb 1.1 root hub device descriptor */
206 static const u8 usb11_rh_dev_descriptor[18] = {
207 	0x12,       /*  __u8  bLength; */
208 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
209 	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
210 
211 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
212 	0x00,	    /*  __u8  bDeviceSubClass; */
213 	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
214 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
215 
216 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
217 	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
218 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
219 
220 	0x03,       /*  __u8  iManufacturer; */
221 	0x02,       /*  __u8  iProduct; */
222 	0x01,       /*  __u8  iSerialNumber; */
223 	0x01        /*  __u8  bNumConfigurations; */
224 };
225 
226 
227 /*-------------------------------------------------------------------------*/
228 
229 /* Configuration descriptors for our root hubs */
230 
231 static const u8 fs_rh_config_descriptor[] = {
232 
233 	/* one configuration */
234 	0x09,       /*  __u8  bLength; */
235 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
236 	0x19, 0x00, /*  __le16 wTotalLength; */
237 	0x01,       /*  __u8  bNumInterfaces; (1) */
238 	0x01,       /*  __u8  bConfigurationValue; */
239 	0x00,       /*  __u8  iConfiguration; */
240 	0xc0,       /*  __u8  bmAttributes;
241 				 Bit 7: must be set,
242 				     6: Self-powered,
243 				     5: Remote wakeup,
244 				     4..0: resvd */
245 	0x00,       /*  __u8  MaxPower; */
246 
247 	/* USB 1.1:
248 	 * USB 2.0, single TT organization (mandatory):
249 	 *	one interface, protocol 0
250 	 *
251 	 * USB 2.0, multiple TT organization (optional):
252 	 *	two interfaces, protocols 1 (like single TT)
253 	 *	and 2 (multiple TT mode) ... config is
254 	 *	sometimes settable
255 	 *	NOT IMPLEMENTED
256 	 */
257 
258 	/* one interface */
259 	0x09,       /*  __u8  if_bLength; */
260 	USB_DT_INTERFACE,  /* __u8 if_bDescriptorType; Interface */
261 	0x00,       /*  __u8  if_bInterfaceNumber; */
262 	0x00,       /*  __u8  if_bAlternateSetting; */
263 	0x01,       /*  __u8  if_bNumEndpoints; */
264 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
265 	0x00,       /*  __u8  if_bInterfaceSubClass; */
266 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
267 	0x00,       /*  __u8  if_iInterface; */
268 
269 	/* one endpoint (status change endpoint) */
270 	0x07,       /*  __u8  ep_bLength; */
271 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
272 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
273 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
274 	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
275 	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
276 };
277 
278 static const u8 hs_rh_config_descriptor[] = {
279 
280 	/* one configuration */
281 	0x09,       /*  __u8  bLength; */
282 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
283 	0x19, 0x00, /*  __le16 wTotalLength; */
284 	0x01,       /*  __u8  bNumInterfaces; (1) */
285 	0x01,       /*  __u8  bConfigurationValue; */
286 	0x00,       /*  __u8  iConfiguration; */
287 	0xc0,       /*  __u8  bmAttributes;
288 				 Bit 7: must be set,
289 				     6: Self-powered,
290 				     5: Remote wakeup,
291 				     4..0: resvd */
292 	0x00,       /*  __u8  MaxPower; */
293 
294 	/* USB 1.1:
295 	 * USB 2.0, single TT organization (mandatory):
296 	 *	one interface, protocol 0
297 	 *
298 	 * USB 2.0, multiple TT organization (optional):
299 	 *	two interfaces, protocols 1 (like single TT)
300 	 *	and 2 (multiple TT mode) ... config is
301 	 *	sometimes settable
302 	 *	NOT IMPLEMENTED
303 	 */
304 
305 	/* one interface */
306 	0x09,       /*  __u8  if_bLength; */
307 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
308 	0x00,       /*  __u8  if_bInterfaceNumber; */
309 	0x00,       /*  __u8  if_bAlternateSetting; */
310 	0x01,       /*  __u8  if_bNumEndpoints; */
311 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
312 	0x00,       /*  __u8  if_bInterfaceSubClass; */
313 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
314 	0x00,       /*  __u8  if_iInterface; */
315 
316 	/* one endpoint (status change endpoint) */
317 	0x07,       /*  __u8  ep_bLength; */
318 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
319 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
320 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
321 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
322 		     * see hub.c:hub_configure() for details. */
323 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
324 	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
325 };
326 
327 static const u8 ss_rh_config_descriptor[] = {
328 	/* one configuration */
329 	0x09,       /*  __u8  bLength; */
330 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
331 	0x1f, 0x00, /*  __le16 wTotalLength; */
332 	0x01,       /*  __u8  bNumInterfaces; (1) */
333 	0x01,       /*  __u8  bConfigurationValue; */
334 	0x00,       /*  __u8  iConfiguration; */
335 	0xc0,       /*  __u8  bmAttributes;
336 				 Bit 7: must be set,
337 				     6: Self-powered,
338 				     5: Remote wakeup,
339 				     4..0: resvd */
340 	0x00,       /*  __u8  MaxPower; */
341 
342 	/* one interface */
343 	0x09,       /*  __u8  if_bLength; */
344 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
345 	0x00,       /*  __u8  if_bInterfaceNumber; */
346 	0x00,       /*  __u8  if_bAlternateSetting; */
347 	0x01,       /*  __u8  if_bNumEndpoints; */
348 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
349 	0x00,       /*  __u8  if_bInterfaceSubClass; */
350 	0x00,       /*  __u8  if_bInterfaceProtocol; */
351 	0x00,       /*  __u8  if_iInterface; */
352 
353 	/* one endpoint (status change endpoint) */
354 	0x07,       /*  __u8  ep_bLength; */
355 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
356 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
357 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
358 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
359 		     * see hub.c:hub_configure() for details. */
360 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
361 	0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
362 
363 	/* one SuperSpeed endpoint companion descriptor */
364 	0x06,        /* __u8 ss_bLength */
365 	USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */
366 		     /* Companion */
367 	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
368 	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
369 	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
370 };
371 
372 /* authorized_default behaviour:
373  * -1 is authorized for all devices except wireless (old behaviour)
374  * 0 is unauthorized for all devices
375  * 1 is authorized for all devices
376  * 2 is authorized for internal devices
377  */
378 #define USB_AUTHORIZE_WIRED	-1
379 #define USB_AUTHORIZE_NONE	0
380 #define USB_AUTHORIZE_ALL	1
381 #define USB_AUTHORIZE_INTERNAL	2
382 
383 static int authorized_default = USB_AUTHORIZE_WIRED;
384 module_param(authorized_default, int, S_IRUGO|S_IWUSR);
385 MODULE_PARM_DESC(authorized_default,
386 		"Default USB device authorization: 0 is not authorized, 1 is "
387 		"authorized, 2 is authorized for internal devices, -1 is "
388 		"authorized except for wireless USB (default, old behaviour)");
389 /*-------------------------------------------------------------------------*/
390 
391 /**
392  * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
393  * @s: Null-terminated ASCII (actually ISO-8859-1) string
394  * @buf: Buffer for USB string descriptor (header + UTF-16LE)
395  * @len: Length (in bytes; may be odd) of descriptor buffer.
396  *
397  * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
398  * whichever is less.
399  *
400  * Note:
401  * USB String descriptors can contain at most 126 characters; input
402  * strings longer than that are truncated.
403  */
404 static unsigned
405 ascii2desc(char const *s, u8 *buf, unsigned len)
406 {
407 	unsigned n, t = 2 + 2*strlen(s);
408 
409 	if (t > 254)
410 		t = 254;	/* Longest possible UTF string descriptor */
411 	if (len > t)
412 		len = t;
413 
414 	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
415 
416 	n = len;
417 	while (n--) {
418 		*buf++ = t;
419 		if (!n--)
420 			break;
421 		*buf++ = t >> 8;
422 		t = (unsigned char)*s++;
423 	}
424 	return len;
425 }
426 
427 /**
428  * rh_string() - provides string descriptors for root hub
429  * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
430  * @hcd: the host controller for this root hub
431  * @data: buffer for output packet
432  * @len: length of the provided buffer
433  *
434  * Produces either a manufacturer, product or serial number string for the
435  * virtual root hub device.
436  *
437  * Return: The number of bytes filled in: the length of the descriptor or
438  * of the provided buffer, whichever is less.
439  */
440 static unsigned
441 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
442 {
443 	char buf[100];
444 	char const *s;
445 	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
446 
447 	/* language ids */
448 	switch (id) {
449 	case 0:
450 		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
451 		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
452 		if (len > 4)
453 			len = 4;
454 		memcpy(data, langids, len);
455 		return len;
456 	case 1:
457 		/* Serial number */
458 		s = hcd->self.bus_name;
459 		break;
460 	case 2:
461 		/* Product name */
462 		s = hcd->product_desc;
463 		break;
464 	case 3:
465 		/* Manufacturer */
466 		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
467 			init_utsname()->release, hcd->driver->description);
468 		s = buf;
469 		break;
470 	default:
471 		/* Can't happen; caller guarantees it */
472 		return 0;
473 	}
474 
475 	return ascii2desc(s, data, len);
476 }
477 
478 
479 /* Root hub control transfers execute synchronously */
480 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
481 {
482 	struct usb_ctrlrequest *cmd;
483 	u16		typeReq, wValue, wIndex, wLength;
484 	u8		*ubuf = urb->transfer_buffer;
485 	unsigned	len = 0;
486 	int		status;
487 	u8		patch_wakeup = 0;
488 	u8		patch_protocol = 0;
489 	u16		tbuf_size;
490 	u8		*tbuf = NULL;
491 	const u8	*bufp;
492 
493 	might_sleep();
494 
495 	spin_lock_irq(&hcd_root_hub_lock);
496 	status = usb_hcd_link_urb_to_ep(hcd, urb);
497 	spin_unlock_irq(&hcd_root_hub_lock);
498 	if (status)
499 		return status;
500 	urb->hcpriv = hcd;	/* Indicate it's queued */
501 
502 	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
503 	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
504 	wValue   = le16_to_cpu (cmd->wValue);
505 	wIndex   = le16_to_cpu (cmd->wIndex);
506 	wLength  = le16_to_cpu (cmd->wLength);
507 
508 	if (wLength > urb->transfer_buffer_length)
509 		goto error;
510 
511 	/*
512 	 * tbuf should be at least as big as the
513 	 * USB hub descriptor.
514 	 */
515 	tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
516 	tbuf = kzalloc(tbuf_size, GFP_KERNEL);
517 	if (!tbuf) {
518 		status = -ENOMEM;
519 		goto err_alloc;
520 	}
521 
522 	bufp = tbuf;
523 
524 
525 	urb->actual_length = 0;
526 	switch (typeReq) {
527 
528 	/* DEVICE REQUESTS */
529 
530 	/* The root hub's remote wakeup enable bit is implemented using
531 	 * driver model wakeup flags.  If this system supports wakeup
532 	 * through USB, userspace may change the default "allow wakeup"
533 	 * policy through sysfs or these calls.
534 	 *
535 	 * Most root hubs support wakeup from downstream devices, for
536 	 * runtime power management (disabling USB clocks and reducing
537 	 * VBUS power usage).  However, not all of them do so; silicon,
538 	 * board, and BIOS bugs here are not uncommon, so these can't
539 	 * be treated quite like external hubs.
540 	 *
541 	 * Likewise, not all root hubs will pass wakeup events upstream,
542 	 * to wake up the whole system.  So don't assume root hub and
543 	 * controller capabilities are identical.
544 	 */
545 
546 	case DeviceRequest | USB_REQ_GET_STATUS:
547 		tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
548 					<< USB_DEVICE_REMOTE_WAKEUP)
549 				| (1 << USB_DEVICE_SELF_POWERED);
550 		tbuf[1] = 0;
551 		len = 2;
552 		break;
553 	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
554 		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
555 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
556 		else
557 			goto error;
558 		break;
559 	case DeviceOutRequest | USB_REQ_SET_FEATURE:
560 		if (device_can_wakeup(&hcd->self.root_hub->dev)
561 				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
562 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
563 		else
564 			goto error;
565 		break;
566 	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
567 		tbuf[0] = 1;
568 		len = 1;
569 			/* FALLTHROUGH */
570 	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
571 		break;
572 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
573 		switch (wValue & 0xff00) {
574 		case USB_DT_DEVICE << 8:
575 			switch (hcd->speed) {
576 			case HCD_USB32:
577 			case HCD_USB31:
578 				bufp = usb31_rh_dev_descriptor;
579 				break;
580 			case HCD_USB3:
581 				bufp = usb3_rh_dev_descriptor;
582 				break;
583 			case HCD_USB25:
584 				bufp = usb25_rh_dev_descriptor;
585 				break;
586 			case HCD_USB2:
587 				bufp = usb2_rh_dev_descriptor;
588 				break;
589 			case HCD_USB11:
590 				bufp = usb11_rh_dev_descriptor;
591 				break;
592 			default:
593 				goto error;
594 			}
595 			len = 18;
596 			if (hcd->has_tt)
597 				patch_protocol = 1;
598 			break;
599 		case USB_DT_CONFIG << 8:
600 			switch (hcd->speed) {
601 			case HCD_USB32:
602 			case HCD_USB31:
603 			case HCD_USB3:
604 				bufp = ss_rh_config_descriptor;
605 				len = sizeof ss_rh_config_descriptor;
606 				break;
607 			case HCD_USB25:
608 			case HCD_USB2:
609 				bufp = hs_rh_config_descriptor;
610 				len = sizeof hs_rh_config_descriptor;
611 				break;
612 			case HCD_USB11:
613 				bufp = fs_rh_config_descriptor;
614 				len = sizeof fs_rh_config_descriptor;
615 				break;
616 			default:
617 				goto error;
618 			}
619 			if (device_can_wakeup(&hcd->self.root_hub->dev))
620 				patch_wakeup = 1;
621 			break;
622 		case USB_DT_STRING << 8:
623 			if ((wValue & 0xff) < 4)
624 				urb->actual_length = rh_string(wValue & 0xff,
625 						hcd, ubuf, wLength);
626 			else /* unsupported IDs --> "protocol stall" */
627 				goto error;
628 			break;
629 		case USB_DT_BOS << 8:
630 			goto nongeneric;
631 		default:
632 			goto error;
633 		}
634 		break;
635 	case DeviceRequest | USB_REQ_GET_INTERFACE:
636 		tbuf[0] = 0;
637 		len = 1;
638 			/* FALLTHROUGH */
639 	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
640 		break;
641 	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
642 		/* wValue == urb->dev->devaddr */
643 		dev_dbg (hcd->self.controller, "root hub device address %d\n",
644 			wValue);
645 		break;
646 
647 	/* INTERFACE REQUESTS (no defined feature/status flags) */
648 
649 	/* ENDPOINT REQUESTS */
650 
651 	case EndpointRequest | USB_REQ_GET_STATUS:
652 		/* ENDPOINT_HALT flag */
653 		tbuf[0] = 0;
654 		tbuf[1] = 0;
655 		len = 2;
656 			/* FALLTHROUGH */
657 	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
658 	case EndpointOutRequest | USB_REQ_SET_FEATURE:
659 		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
660 		break;
661 
662 	/* CLASS REQUESTS (and errors) */
663 
664 	default:
665 nongeneric:
666 		/* non-generic request */
667 		switch (typeReq) {
668 		case GetHubStatus:
669 			len = 4;
670 			break;
671 		case GetPortStatus:
672 			if (wValue == HUB_PORT_STATUS)
673 				len = 4;
674 			else
675 				/* other port status types return 8 bytes */
676 				len = 8;
677 			break;
678 		case GetHubDescriptor:
679 			len = sizeof (struct usb_hub_descriptor);
680 			break;
681 		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
682 			/* len is returned by hub_control */
683 			break;
684 		}
685 		status = hcd->driver->hub_control (hcd,
686 			typeReq, wValue, wIndex,
687 			tbuf, wLength);
688 
689 		if (typeReq == GetHubDescriptor)
690 			usb_hub_adjust_deviceremovable(hcd->self.root_hub,
691 				(struct usb_hub_descriptor *)tbuf);
692 		break;
693 error:
694 		/* "protocol stall" on error */
695 		status = -EPIPE;
696 	}
697 
698 	if (status < 0) {
699 		len = 0;
700 		if (status != -EPIPE) {
701 			dev_dbg (hcd->self.controller,
702 				"CTRL: TypeReq=0x%x val=0x%x "
703 				"idx=0x%x len=%d ==> %d\n",
704 				typeReq, wValue, wIndex,
705 				wLength, status);
706 		}
707 	} else if (status > 0) {
708 		/* hub_control may return the length of data copied. */
709 		len = status;
710 		status = 0;
711 	}
712 	if (len) {
713 		if (urb->transfer_buffer_length < len)
714 			len = urb->transfer_buffer_length;
715 		urb->actual_length = len;
716 		/* always USB_DIR_IN, toward host */
717 		memcpy (ubuf, bufp, len);
718 
719 		/* report whether RH hardware supports remote wakeup */
720 		if (patch_wakeup &&
721 				len > offsetof (struct usb_config_descriptor,
722 						bmAttributes))
723 			((struct usb_config_descriptor *)ubuf)->bmAttributes
724 				|= USB_CONFIG_ATT_WAKEUP;
725 
726 		/* report whether RH hardware has an integrated TT */
727 		if (patch_protocol &&
728 				len > offsetof(struct usb_device_descriptor,
729 						bDeviceProtocol))
730 			((struct usb_device_descriptor *) ubuf)->
731 				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
732 	}
733 
734 	kfree(tbuf);
735  err_alloc:
736 
737 	/* any errors get returned through the urb completion */
738 	spin_lock_irq(&hcd_root_hub_lock);
739 	usb_hcd_unlink_urb_from_ep(hcd, urb);
740 	usb_hcd_giveback_urb(hcd, urb, status);
741 	spin_unlock_irq(&hcd_root_hub_lock);
742 	return 0;
743 }
744 
745 /*-------------------------------------------------------------------------*/
746 
747 /*
748  * Root Hub interrupt transfers are polled using a timer if the
749  * driver requests it; otherwise the driver is responsible for
750  * calling usb_hcd_poll_rh_status() when an event occurs.
751  *
752  * Completions are called in_interrupt(), but they may or may not
753  * be in_irq().
754  */
755 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
756 {
757 	struct urb	*urb;
758 	int		length;
759 	unsigned long	flags;
760 	char		buffer[6];	/* Any root hubs with > 31 ports? */
761 
762 	if (unlikely(!hcd->rh_pollable))
763 		return;
764 	if (!hcd->uses_new_polling && !hcd->status_urb)
765 		return;
766 
767 	length = hcd->driver->hub_status_data(hcd, buffer);
768 	if (length > 0) {
769 
770 		/* try to complete the status urb */
771 		spin_lock_irqsave(&hcd_root_hub_lock, flags);
772 		urb = hcd->status_urb;
773 		if (urb) {
774 			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
775 			hcd->status_urb = NULL;
776 			urb->actual_length = length;
777 			memcpy(urb->transfer_buffer, buffer, length);
778 
779 			usb_hcd_unlink_urb_from_ep(hcd, urb);
780 			usb_hcd_giveback_urb(hcd, urb, 0);
781 		} else {
782 			length = 0;
783 			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
784 		}
785 		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
786 	}
787 
788 	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
789 	 * exceed that limit if HZ is 100. The math is more clunky than
790 	 * maybe expected, this is to make sure that all timers for USB devices
791 	 * fire at the same time to give the CPU a break in between */
792 	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
793 			(length == 0 && hcd->status_urb != NULL))
794 		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
795 }
796 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
797 
798 /* timer callback */
799 static void rh_timer_func (struct timer_list *t)
800 {
801 	struct usb_hcd *_hcd = from_timer(_hcd, t, rh_timer);
802 
803 	usb_hcd_poll_rh_status(_hcd);
804 }
805 
806 /*-------------------------------------------------------------------------*/
807 
808 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
809 {
810 	int		retval;
811 	unsigned long	flags;
812 	unsigned	len = 1 + (urb->dev->maxchild / 8);
813 
814 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
815 	if (hcd->status_urb || urb->transfer_buffer_length < len) {
816 		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
817 		retval = -EINVAL;
818 		goto done;
819 	}
820 
821 	retval = usb_hcd_link_urb_to_ep(hcd, urb);
822 	if (retval)
823 		goto done;
824 
825 	hcd->status_urb = urb;
826 	urb->hcpriv = hcd;	/* indicate it's queued */
827 	if (!hcd->uses_new_polling)
828 		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
829 
830 	/* If a status change has already occurred, report it ASAP */
831 	else if (HCD_POLL_PENDING(hcd))
832 		mod_timer(&hcd->rh_timer, jiffies);
833 	retval = 0;
834  done:
835 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
836 	return retval;
837 }
838 
839 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
840 {
841 	if (usb_endpoint_xfer_int(&urb->ep->desc))
842 		return rh_queue_status (hcd, urb);
843 	if (usb_endpoint_xfer_control(&urb->ep->desc))
844 		return rh_call_control (hcd, urb);
845 	return -EINVAL;
846 }
847 
848 /*-------------------------------------------------------------------------*/
849 
850 /* Unlinks of root-hub control URBs are legal, but they don't do anything
851  * since these URBs always execute synchronously.
852  */
853 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
854 {
855 	unsigned long	flags;
856 	int		rc;
857 
858 	spin_lock_irqsave(&hcd_root_hub_lock, flags);
859 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
860 	if (rc)
861 		goto done;
862 
863 	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
864 		;	/* Do nothing */
865 
866 	} else {				/* Status URB */
867 		if (!hcd->uses_new_polling)
868 			del_timer (&hcd->rh_timer);
869 		if (urb == hcd->status_urb) {
870 			hcd->status_urb = NULL;
871 			usb_hcd_unlink_urb_from_ep(hcd, urb);
872 			usb_hcd_giveback_urb(hcd, urb, status);
873 		}
874 	}
875  done:
876 	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
877 	return rc;
878 }
879 
880 
881 
882 /*
883  * Show & store the current value of authorized_default
884  */
885 static ssize_t authorized_default_show(struct device *dev,
886 				       struct device_attribute *attr, char *buf)
887 {
888 	struct usb_device *rh_usb_dev = to_usb_device(dev);
889 	struct usb_bus *usb_bus = rh_usb_dev->bus;
890 	struct usb_hcd *hcd;
891 
892 	hcd = bus_to_hcd(usb_bus);
893 	return snprintf(buf, PAGE_SIZE, "%u\n", hcd->dev_policy);
894 }
895 
896 static ssize_t authorized_default_store(struct device *dev,
897 					struct device_attribute *attr,
898 					const char *buf, size_t size)
899 {
900 	ssize_t result;
901 	unsigned val;
902 	struct usb_device *rh_usb_dev = to_usb_device(dev);
903 	struct usb_bus *usb_bus = rh_usb_dev->bus;
904 	struct usb_hcd *hcd;
905 
906 	hcd = bus_to_hcd(usb_bus);
907 	result = sscanf(buf, "%u\n", &val);
908 	if (result == 1) {
909 		hcd->dev_policy = val <= USB_DEVICE_AUTHORIZE_INTERNAL ?
910 			val : USB_DEVICE_AUTHORIZE_ALL;
911 		result = size;
912 	} else {
913 		result = -EINVAL;
914 	}
915 	return result;
916 }
917 static DEVICE_ATTR_RW(authorized_default);
918 
919 /*
920  * interface_authorized_default_show - show default authorization status
921  * for USB interfaces
922  *
923  * note: interface_authorized_default is the default value
924  *       for initializing the authorized attribute of interfaces
925  */
926 static ssize_t interface_authorized_default_show(struct device *dev,
927 		struct device_attribute *attr, char *buf)
928 {
929 	struct usb_device *usb_dev = to_usb_device(dev);
930 	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
931 
932 	return sprintf(buf, "%u\n", !!HCD_INTF_AUTHORIZED(hcd));
933 }
934 
935 /*
936  * interface_authorized_default_store - store default authorization status
937  * for USB interfaces
938  *
939  * note: interface_authorized_default is the default value
940  *       for initializing the authorized attribute of interfaces
941  */
942 static ssize_t interface_authorized_default_store(struct device *dev,
943 		struct device_attribute *attr, const char *buf, size_t count)
944 {
945 	struct usb_device *usb_dev = to_usb_device(dev);
946 	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
947 	int rc = count;
948 	bool val;
949 
950 	if (strtobool(buf, &val) != 0)
951 		return -EINVAL;
952 
953 	if (val)
954 		set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
955 	else
956 		clear_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
957 
958 	return rc;
959 }
960 static DEVICE_ATTR_RW(interface_authorized_default);
961 
962 /* Group all the USB bus attributes */
963 static struct attribute *usb_bus_attrs[] = {
964 		&dev_attr_authorized_default.attr,
965 		&dev_attr_interface_authorized_default.attr,
966 		NULL,
967 };
968 
969 static const struct attribute_group usb_bus_attr_group = {
970 	.name = NULL,	/* we want them in the same directory */
971 	.attrs = usb_bus_attrs,
972 };
973 
974 
975 
976 /*-------------------------------------------------------------------------*/
977 
978 /**
979  * usb_bus_init - shared initialization code
980  * @bus: the bus structure being initialized
981  *
982  * This code is used to initialize a usb_bus structure, memory for which is
983  * separately managed.
984  */
985 static void usb_bus_init (struct usb_bus *bus)
986 {
987 	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
988 
989 	bus->devnum_next = 1;
990 
991 	bus->root_hub = NULL;
992 	bus->busnum = -1;
993 	bus->bandwidth_allocated = 0;
994 	bus->bandwidth_int_reqs  = 0;
995 	bus->bandwidth_isoc_reqs = 0;
996 	mutex_init(&bus->devnum_next_mutex);
997 }
998 
999 /*-------------------------------------------------------------------------*/
1000 
1001 /**
1002  * usb_register_bus - registers the USB host controller with the usb core
1003  * @bus: pointer to the bus to register
1004  * Context: !in_interrupt()
1005  *
1006  * Assigns a bus number, and links the controller into usbcore data
1007  * structures so that it can be seen by scanning the bus list.
1008  *
1009  * Return: 0 if successful. A negative error code otherwise.
1010  */
1011 static int usb_register_bus(struct usb_bus *bus)
1012 {
1013 	int result = -E2BIG;
1014 	int busnum;
1015 
1016 	mutex_lock(&usb_bus_idr_lock);
1017 	busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL);
1018 	if (busnum < 0) {
1019 		pr_err("%s: failed to get bus number\n", usbcore_name);
1020 		goto error_find_busnum;
1021 	}
1022 	bus->busnum = busnum;
1023 	mutex_unlock(&usb_bus_idr_lock);
1024 
1025 	usb_notify_add_bus(bus);
1026 
1027 	dev_info (bus->controller, "new USB bus registered, assigned bus "
1028 		  "number %d\n", bus->busnum);
1029 	return 0;
1030 
1031 error_find_busnum:
1032 	mutex_unlock(&usb_bus_idr_lock);
1033 	return result;
1034 }
1035 
1036 /**
1037  * usb_deregister_bus - deregisters the USB host controller
1038  * @bus: pointer to the bus to deregister
1039  * Context: !in_interrupt()
1040  *
1041  * Recycles the bus number, and unlinks the controller from usbcore data
1042  * structures so that it won't be seen by scanning the bus list.
1043  */
1044 static void usb_deregister_bus (struct usb_bus *bus)
1045 {
1046 	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
1047 
1048 	/*
1049 	 * NOTE: make sure that all the devices are removed by the
1050 	 * controller code, as well as having it call this when cleaning
1051 	 * itself up
1052 	 */
1053 	mutex_lock(&usb_bus_idr_lock);
1054 	idr_remove(&usb_bus_idr, bus->busnum);
1055 	mutex_unlock(&usb_bus_idr_lock);
1056 
1057 	usb_notify_remove_bus(bus);
1058 }
1059 
1060 /**
1061  * register_root_hub - called by usb_add_hcd() to register a root hub
1062  * @hcd: host controller for this root hub
1063  *
1064  * This function registers the root hub with the USB subsystem.  It sets up
1065  * the device properly in the device tree and then calls usb_new_device()
1066  * to register the usb device.  It also assigns the root hub's USB address
1067  * (always 1).
1068  *
1069  * Return: 0 if successful. A negative error code otherwise.
1070  */
1071 static int register_root_hub(struct usb_hcd *hcd)
1072 {
1073 	struct device *parent_dev = hcd->self.controller;
1074 	struct usb_device *usb_dev = hcd->self.root_hub;
1075 	const int devnum = 1;
1076 	int retval;
1077 
1078 	usb_dev->devnum = devnum;
1079 	usb_dev->bus->devnum_next = devnum + 1;
1080 	set_bit (devnum, usb_dev->bus->devmap.devicemap);
1081 	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
1082 
1083 	mutex_lock(&usb_bus_idr_lock);
1084 
1085 	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
1086 	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
1087 	if (retval != sizeof usb_dev->descriptor) {
1088 		mutex_unlock(&usb_bus_idr_lock);
1089 		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
1090 				dev_name(&usb_dev->dev), retval);
1091 		return (retval < 0) ? retval : -EMSGSIZE;
1092 	}
1093 
1094 	if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
1095 		retval = usb_get_bos_descriptor(usb_dev);
1096 		if (!retval) {
1097 			usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
1098 		} else if (usb_dev->speed >= USB_SPEED_SUPER) {
1099 			mutex_unlock(&usb_bus_idr_lock);
1100 			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1101 					dev_name(&usb_dev->dev), retval);
1102 			return retval;
1103 		}
1104 	}
1105 
1106 	retval = usb_new_device (usb_dev);
1107 	if (retval) {
1108 		dev_err (parent_dev, "can't register root hub for %s, %d\n",
1109 				dev_name(&usb_dev->dev), retval);
1110 	} else {
1111 		spin_lock_irq (&hcd_root_hub_lock);
1112 		hcd->rh_registered = 1;
1113 		spin_unlock_irq (&hcd_root_hub_lock);
1114 
1115 		/* Did the HC die before the root hub was registered? */
1116 		if (HCD_DEAD(hcd))
1117 			usb_hc_died (hcd);	/* This time clean up */
1118 	}
1119 	mutex_unlock(&usb_bus_idr_lock);
1120 
1121 	return retval;
1122 }
1123 
1124 /*
1125  * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1126  * @bus: the bus which the root hub belongs to
1127  * @portnum: the port which is being resumed
1128  *
1129  * HCDs should call this function when they know that a resume signal is
1130  * being sent to a root-hub port.  The root hub will be prevented from
1131  * going into autosuspend until usb_hcd_end_port_resume() is called.
1132  *
1133  * The bus's private lock must be held by the caller.
1134  */
1135 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1136 {
1137 	unsigned bit = 1 << portnum;
1138 
1139 	if (!(bus->resuming_ports & bit)) {
1140 		bus->resuming_ports |= bit;
1141 		pm_runtime_get_noresume(&bus->root_hub->dev);
1142 	}
1143 }
1144 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1145 
1146 /*
1147  * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1148  * @bus: the bus which the root hub belongs to
1149  * @portnum: the port which is being resumed
1150  *
1151  * HCDs should call this function when they know that a resume signal has
1152  * stopped being sent to a root-hub port.  The root hub will be allowed to
1153  * autosuspend again.
1154  *
1155  * The bus's private lock must be held by the caller.
1156  */
1157 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1158 {
1159 	unsigned bit = 1 << portnum;
1160 
1161 	if (bus->resuming_ports & bit) {
1162 		bus->resuming_ports &= ~bit;
1163 		pm_runtime_put_noidle(&bus->root_hub->dev);
1164 	}
1165 }
1166 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1167 
1168 /*-------------------------------------------------------------------------*/
1169 
1170 /**
1171  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1172  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1173  * @is_input: true iff the transaction sends data to the host
1174  * @isoc: true for isochronous transactions, false for interrupt ones
1175  * @bytecount: how many bytes in the transaction.
1176  *
1177  * Return: Approximate bus time in nanoseconds for a periodic transaction.
1178  *
1179  * Note:
1180  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1181  * scheduled in software, this function is only used for such scheduling.
1182  */
1183 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1184 {
1185 	unsigned long	tmp;
1186 
1187 	switch (speed) {
1188 	case USB_SPEED_LOW: 	/* INTR only */
1189 		if (is_input) {
1190 			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1191 			return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1192 		} else {
1193 			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1194 			return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1195 		}
1196 	case USB_SPEED_FULL:	/* ISOC or INTR */
1197 		if (isoc) {
1198 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1199 			return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1200 		} else {
1201 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1202 			return 9107L + BW_HOST_DELAY + tmp;
1203 		}
1204 	case USB_SPEED_HIGH:	/* ISOC or INTR */
1205 		/* FIXME adjust for input vs output */
1206 		if (isoc)
1207 			tmp = HS_NSECS_ISO (bytecount);
1208 		else
1209 			tmp = HS_NSECS (bytecount);
1210 		return tmp;
1211 	default:
1212 		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1213 		return -1;
1214 	}
1215 }
1216 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1217 
1218 
1219 /*-------------------------------------------------------------------------*/
1220 
1221 /*
1222  * Generic HC operations.
1223  */
1224 
1225 /*-------------------------------------------------------------------------*/
1226 
1227 /**
1228  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1229  * @hcd: host controller to which @urb was submitted
1230  * @urb: URB being submitted
1231  *
1232  * Host controller drivers should call this routine in their enqueue()
1233  * method.  The HCD's private spinlock must be held and interrupts must
1234  * be disabled.  The actions carried out here are required for URB
1235  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1236  *
1237  * Return: 0 for no error, otherwise a negative error code (in which case
1238  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1239  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1240  * the private spinlock and returning.
1241  */
1242 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1243 {
1244 	int		rc = 0;
1245 
1246 	spin_lock(&hcd_urb_list_lock);
1247 
1248 	/* Check that the URB isn't being killed */
1249 	if (unlikely(atomic_read(&urb->reject))) {
1250 		rc = -EPERM;
1251 		goto done;
1252 	}
1253 
1254 	if (unlikely(!urb->ep->enabled)) {
1255 		rc = -ENOENT;
1256 		goto done;
1257 	}
1258 
1259 	if (unlikely(!urb->dev->can_submit)) {
1260 		rc = -EHOSTUNREACH;
1261 		goto done;
1262 	}
1263 
1264 	/*
1265 	 * Check the host controller's state and add the URB to the
1266 	 * endpoint's queue.
1267 	 */
1268 	if (HCD_RH_RUNNING(hcd)) {
1269 		urb->unlinked = 0;
1270 		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1271 	} else {
1272 		rc = -ESHUTDOWN;
1273 		goto done;
1274 	}
1275  done:
1276 	spin_unlock(&hcd_urb_list_lock);
1277 	return rc;
1278 }
1279 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1280 
1281 /**
1282  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1283  * @hcd: host controller to which @urb was submitted
1284  * @urb: URB being checked for unlinkability
1285  * @status: error code to store in @urb if the unlink succeeds
1286  *
1287  * Host controller drivers should call this routine in their dequeue()
1288  * method.  The HCD's private spinlock must be held and interrupts must
1289  * be disabled.  The actions carried out here are required for making
1290  * sure than an unlink is valid.
1291  *
1292  * Return: 0 for no error, otherwise a negative error code (in which case
1293  * the dequeue() method must fail).  The possible error codes are:
1294  *
1295  *	-EIDRM: @urb was not submitted or has already completed.
1296  *		The completion function may not have been called yet.
1297  *
1298  *	-EBUSY: @urb has already been unlinked.
1299  */
1300 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1301 		int status)
1302 {
1303 	struct list_head	*tmp;
1304 
1305 	/* insist the urb is still queued */
1306 	list_for_each(tmp, &urb->ep->urb_list) {
1307 		if (tmp == &urb->urb_list)
1308 			break;
1309 	}
1310 	if (tmp != &urb->urb_list)
1311 		return -EIDRM;
1312 
1313 	/* Any status except -EINPROGRESS means something already started to
1314 	 * unlink this URB from the hardware.  So there's no more work to do.
1315 	 */
1316 	if (urb->unlinked)
1317 		return -EBUSY;
1318 	urb->unlinked = status;
1319 	return 0;
1320 }
1321 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1322 
1323 /**
1324  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1325  * @hcd: host controller to which @urb was submitted
1326  * @urb: URB being unlinked
1327  *
1328  * Host controller drivers should call this routine before calling
1329  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1330  * interrupts must be disabled.  The actions carried out here are required
1331  * for URB completion.
1332  */
1333 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1334 {
1335 	/* clear all state linking urb to this dev (and hcd) */
1336 	spin_lock(&hcd_urb_list_lock);
1337 	list_del_init(&urb->urb_list);
1338 	spin_unlock(&hcd_urb_list_lock);
1339 }
1340 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1341 
1342 /*
1343  * Some usb host controllers can only perform dma using a small SRAM area.
1344  * The usb core itself is however optimized for host controllers that can dma
1345  * using regular system memory - like pci devices doing bus mastering.
1346  *
1347  * To support host controllers with limited dma capabilities we provide dma
1348  * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag.
1349  * For this to work properly the host controller code must first use the
1350  * function dma_declare_coherent_memory() to point out which memory area
1351  * that should be used for dma allocations.
1352  *
1353  * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for
1354  * dma using dma_alloc_coherent() which in turn allocates from the memory
1355  * area pointed out with dma_declare_coherent_memory().
1356  *
1357  * So, to summarize...
1358  *
1359  * - We need "local" memory, canonical example being
1360  *   a small SRAM on a discrete controller being the
1361  *   only memory that the controller can read ...
1362  *   (a) "normal" kernel memory is no good, and
1363  *   (b) there's not enough to share
1364  *
1365  * - The only *portable* hook for such stuff in the
1366  *   DMA framework is dma_declare_coherent_memory()
1367  *
1368  * - So we use that, even though the primary requirement
1369  *   is that the memory be "local" (hence addressable
1370  *   by that device), not "coherent".
1371  *
1372  */
1373 
1374 static int hcd_alloc_coherent(struct usb_bus *bus,
1375 			      gfp_t mem_flags, dma_addr_t *dma_handle,
1376 			      void **vaddr_handle, size_t size,
1377 			      enum dma_data_direction dir)
1378 {
1379 	unsigned char *vaddr;
1380 
1381 	if (*vaddr_handle == NULL) {
1382 		WARN_ON_ONCE(1);
1383 		return -EFAULT;
1384 	}
1385 
1386 	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1387 				 mem_flags, dma_handle);
1388 	if (!vaddr)
1389 		return -ENOMEM;
1390 
1391 	/*
1392 	 * Store the virtual address of the buffer at the end
1393 	 * of the allocated dma buffer. The size of the buffer
1394 	 * may be uneven so use unaligned functions instead
1395 	 * of just rounding up. It makes sense to optimize for
1396 	 * memory footprint over access speed since the amount
1397 	 * of memory available for dma may be limited.
1398 	 */
1399 	put_unaligned((unsigned long)*vaddr_handle,
1400 		      (unsigned long *)(vaddr + size));
1401 
1402 	if (dir == DMA_TO_DEVICE)
1403 		memcpy(vaddr, *vaddr_handle, size);
1404 
1405 	*vaddr_handle = vaddr;
1406 	return 0;
1407 }
1408 
1409 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1410 			      void **vaddr_handle, size_t size,
1411 			      enum dma_data_direction dir)
1412 {
1413 	unsigned char *vaddr = *vaddr_handle;
1414 
1415 	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1416 
1417 	if (dir == DMA_FROM_DEVICE)
1418 		memcpy(vaddr, *vaddr_handle, size);
1419 
1420 	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1421 
1422 	*vaddr_handle = vaddr;
1423 	*dma_handle = 0;
1424 }
1425 
1426 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1427 {
1428 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1429 	    (urb->transfer_flags & URB_SETUP_MAP_SINGLE))
1430 		dma_unmap_single(hcd->self.sysdev,
1431 				urb->setup_dma,
1432 				sizeof(struct usb_ctrlrequest),
1433 				DMA_TO_DEVICE);
1434 	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1435 		hcd_free_coherent(urb->dev->bus,
1436 				&urb->setup_dma,
1437 				(void **) &urb->setup_packet,
1438 				sizeof(struct usb_ctrlrequest),
1439 				DMA_TO_DEVICE);
1440 
1441 	/* Make it safe to call this routine more than once */
1442 	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1443 }
1444 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1445 
1446 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1447 {
1448 	if (hcd->driver->unmap_urb_for_dma)
1449 		hcd->driver->unmap_urb_for_dma(hcd, urb);
1450 	else
1451 		usb_hcd_unmap_urb_for_dma(hcd, urb);
1452 }
1453 
1454 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1455 {
1456 	enum dma_data_direction dir;
1457 
1458 	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1459 
1460 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1461 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1462 	    (urb->transfer_flags & URB_DMA_MAP_SG))
1463 		dma_unmap_sg(hcd->self.sysdev,
1464 				urb->sg,
1465 				urb->num_sgs,
1466 				dir);
1467 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1468 		 (urb->transfer_flags & URB_DMA_MAP_PAGE))
1469 		dma_unmap_page(hcd->self.sysdev,
1470 				urb->transfer_dma,
1471 				urb->transfer_buffer_length,
1472 				dir);
1473 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1474 		 (urb->transfer_flags & URB_DMA_MAP_SINGLE))
1475 		dma_unmap_single(hcd->self.sysdev,
1476 				urb->transfer_dma,
1477 				urb->transfer_buffer_length,
1478 				dir);
1479 	else if (urb->transfer_flags & URB_MAP_LOCAL)
1480 		hcd_free_coherent(urb->dev->bus,
1481 				&urb->transfer_dma,
1482 				&urb->transfer_buffer,
1483 				urb->transfer_buffer_length,
1484 				dir);
1485 
1486 	/* Make it safe to call this routine more than once */
1487 	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1488 			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1489 }
1490 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1491 
1492 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1493 			   gfp_t mem_flags)
1494 {
1495 	if (hcd->driver->map_urb_for_dma)
1496 		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1497 	else
1498 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1499 }
1500 
1501 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1502 			    gfp_t mem_flags)
1503 {
1504 	enum dma_data_direction dir;
1505 	int ret = 0;
1506 
1507 	/* Map the URB's buffers for DMA access.
1508 	 * Lower level HCD code should use *_dma exclusively,
1509 	 * unless it uses pio or talks to another transport,
1510 	 * or uses the provided scatter gather list for bulk.
1511 	 */
1512 
1513 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1514 		if (hcd->self.uses_pio_for_control)
1515 			return ret;
1516 		if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) {
1517 			if (is_vmalloc_addr(urb->setup_packet)) {
1518 				WARN_ONCE(1, "setup packet is not dma capable\n");
1519 				return -EAGAIN;
1520 			} else if (object_is_on_stack(urb->setup_packet)) {
1521 				WARN_ONCE(1, "setup packet is on stack\n");
1522 				return -EAGAIN;
1523 			}
1524 
1525 			urb->setup_dma = dma_map_single(
1526 					hcd->self.sysdev,
1527 					urb->setup_packet,
1528 					sizeof(struct usb_ctrlrequest),
1529 					DMA_TO_DEVICE);
1530 			if (dma_mapping_error(hcd->self.sysdev,
1531 						urb->setup_dma))
1532 				return -EAGAIN;
1533 			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1534 		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1535 			ret = hcd_alloc_coherent(
1536 					urb->dev->bus, mem_flags,
1537 					&urb->setup_dma,
1538 					(void **)&urb->setup_packet,
1539 					sizeof(struct usb_ctrlrequest),
1540 					DMA_TO_DEVICE);
1541 			if (ret)
1542 				return ret;
1543 			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1544 		}
1545 	}
1546 
1547 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1548 	if (urb->transfer_buffer_length != 0
1549 	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1550 		if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) {
1551 			if (urb->num_sgs) {
1552 				int n;
1553 
1554 				/* We don't support sg for isoc transfers ! */
1555 				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1556 					WARN_ON(1);
1557 					return -EINVAL;
1558 				}
1559 
1560 				n = dma_map_sg(
1561 						hcd->self.sysdev,
1562 						urb->sg,
1563 						urb->num_sgs,
1564 						dir);
1565 				if (n <= 0)
1566 					ret = -EAGAIN;
1567 				else
1568 					urb->transfer_flags |= URB_DMA_MAP_SG;
1569 				urb->num_mapped_sgs = n;
1570 				if (n != urb->num_sgs)
1571 					urb->transfer_flags |=
1572 							URB_DMA_SG_COMBINED;
1573 			} else if (urb->sg) {
1574 				struct scatterlist *sg = urb->sg;
1575 				urb->transfer_dma = dma_map_page(
1576 						hcd->self.sysdev,
1577 						sg_page(sg),
1578 						sg->offset,
1579 						urb->transfer_buffer_length,
1580 						dir);
1581 				if (dma_mapping_error(hcd->self.sysdev,
1582 						urb->transfer_dma))
1583 					ret = -EAGAIN;
1584 				else
1585 					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1586 			} else if (is_vmalloc_addr(urb->transfer_buffer)) {
1587 				WARN_ONCE(1, "transfer buffer not dma capable\n");
1588 				ret = -EAGAIN;
1589 			} else if (object_is_on_stack(urb->transfer_buffer)) {
1590 				WARN_ONCE(1, "transfer buffer is on stack\n");
1591 				ret = -EAGAIN;
1592 			} else {
1593 				urb->transfer_dma = dma_map_single(
1594 						hcd->self.sysdev,
1595 						urb->transfer_buffer,
1596 						urb->transfer_buffer_length,
1597 						dir);
1598 				if (dma_mapping_error(hcd->self.sysdev,
1599 						urb->transfer_dma))
1600 					ret = -EAGAIN;
1601 				else
1602 					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1603 			}
1604 		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1605 			ret = hcd_alloc_coherent(
1606 					urb->dev->bus, mem_flags,
1607 					&urb->transfer_dma,
1608 					&urb->transfer_buffer,
1609 					urb->transfer_buffer_length,
1610 					dir);
1611 			if (ret == 0)
1612 				urb->transfer_flags |= URB_MAP_LOCAL;
1613 		}
1614 		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1615 				URB_SETUP_MAP_LOCAL)))
1616 			usb_hcd_unmap_urb_for_dma(hcd, urb);
1617 	}
1618 	return ret;
1619 }
1620 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1621 
1622 /*-------------------------------------------------------------------------*/
1623 
1624 /* may be called in any context with a valid urb->dev usecount
1625  * caller surrenders "ownership" of urb
1626  * expects usb_submit_urb() to have sanity checked and conditioned all
1627  * inputs in the urb
1628  */
1629 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1630 {
1631 	int			status;
1632 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1633 
1634 	/* increment urb's reference count as part of giving it to the HCD
1635 	 * (which will control it).  HCD guarantees that it either returns
1636 	 * an error or calls giveback(), but not both.
1637 	 */
1638 	usb_get_urb(urb);
1639 	atomic_inc(&urb->use_count);
1640 	atomic_inc(&urb->dev->urbnum);
1641 	usbmon_urb_submit(&hcd->self, urb);
1642 
1643 	/* NOTE requirements on root-hub callers (usbfs and the hub
1644 	 * driver, for now):  URBs' urb->transfer_buffer must be
1645 	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1646 	 * they could clobber root hub response data.  Also, control
1647 	 * URBs must be submitted in process context with interrupts
1648 	 * enabled.
1649 	 */
1650 
1651 	if (is_root_hub(urb->dev)) {
1652 		status = rh_urb_enqueue(hcd, urb);
1653 	} else {
1654 		status = map_urb_for_dma(hcd, urb, mem_flags);
1655 		if (likely(status == 0)) {
1656 			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1657 			if (unlikely(status))
1658 				unmap_urb_for_dma(hcd, urb);
1659 		}
1660 	}
1661 
1662 	if (unlikely(status)) {
1663 		usbmon_urb_submit_error(&hcd->self, urb, status);
1664 		urb->hcpriv = NULL;
1665 		INIT_LIST_HEAD(&urb->urb_list);
1666 		atomic_dec(&urb->use_count);
1667 		atomic_dec(&urb->dev->urbnum);
1668 		if (atomic_read(&urb->reject))
1669 			wake_up(&usb_kill_urb_queue);
1670 		usb_put_urb(urb);
1671 	}
1672 	return status;
1673 }
1674 
1675 /*-------------------------------------------------------------------------*/
1676 
1677 /* this makes the hcd giveback() the urb more quickly, by kicking it
1678  * off hardware queues (which may take a while) and returning it as
1679  * soon as practical.  we've already set up the urb's return status,
1680  * but we can't know if the callback completed already.
1681  */
1682 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1683 {
1684 	int		value;
1685 
1686 	if (is_root_hub(urb->dev))
1687 		value = usb_rh_urb_dequeue(hcd, urb, status);
1688 	else {
1689 
1690 		/* The only reason an HCD might fail this call is if
1691 		 * it has not yet fully queued the urb to begin with.
1692 		 * Such failures should be harmless. */
1693 		value = hcd->driver->urb_dequeue(hcd, urb, status);
1694 	}
1695 	return value;
1696 }
1697 
1698 /*
1699  * called in any context
1700  *
1701  * caller guarantees urb won't be recycled till both unlink()
1702  * and the urb's completion function return
1703  */
1704 int usb_hcd_unlink_urb (struct urb *urb, int status)
1705 {
1706 	struct usb_hcd		*hcd;
1707 	struct usb_device	*udev = urb->dev;
1708 	int			retval = -EIDRM;
1709 	unsigned long		flags;
1710 
1711 	/* Prevent the device and bus from going away while
1712 	 * the unlink is carried out.  If they are already gone
1713 	 * then urb->use_count must be 0, since disconnected
1714 	 * devices can't have any active URBs.
1715 	 */
1716 	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1717 	if (atomic_read(&urb->use_count) > 0) {
1718 		retval = 0;
1719 		usb_get_dev(udev);
1720 	}
1721 	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1722 	if (retval == 0) {
1723 		hcd = bus_to_hcd(urb->dev->bus);
1724 		retval = unlink1(hcd, urb, status);
1725 		if (retval == 0)
1726 			retval = -EINPROGRESS;
1727 		else if (retval != -EIDRM && retval != -EBUSY)
1728 			dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n",
1729 					urb, retval);
1730 		usb_put_dev(udev);
1731 	}
1732 	return retval;
1733 }
1734 
1735 /*-------------------------------------------------------------------------*/
1736 
1737 static void __usb_hcd_giveback_urb(struct urb *urb)
1738 {
1739 	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1740 	struct usb_anchor *anchor = urb->anchor;
1741 	int status = urb->unlinked;
1742 
1743 	urb->hcpriv = NULL;
1744 	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1745 	    urb->actual_length < urb->transfer_buffer_length &&
1746 	    !status))
1747 		status = -EREMOTEIO;
1748 
1749 	unmap_urb_for_dma(hcd, urb);
1750 	usbmon_urb_complete(&hcd->self, urb, status);
1751 	usb_anchor_suspend_wakeups(anchor);
1752 	usb_unanchor_urb(urb);
1753 	if (likely(status == 0))
1754 		usb_led_activity(USB_LED_EVENT_HOST);
1755 
1756 	/* pass ownership to the completion handler */
1757 	urb->status = status;
1758 	urb->complete(urb);
1759 
1760 	usb_anchor_resume_wakeups(anchor);
1761 	atomic_dec(&urb->use_count);
1762 	if (unlikely(atomic_read(&urb->reject)))
1763 		wake_up(&usb_kill_urb_queue);
1764 	usb_put_urb(urb);
1765 }
1766 
1767 static void usb_giveback_urb_bh(unsigned long param)
1768 {
1769 	struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param;
1770 	struct list_head local_list;
1771 
1772 	spin_lock_irq(&bh->lock);
1773 	bh->running = true;
1774  restart:
1775 	list_replace_init(&bh->head, &local_list);
1776 	spin_unlock_irq(&bh->lock);
1777 
1778 	while (!list_empty(&local_list)) {
1779 		struct urb *urb;
1780 
1781 		urb = list_entry(local_list.next, struct urb, urb_list);
1782 		list_del_init(&urb->urb_list);
1783 		bh->completing_ep = urb->ep;
1784 		__usb_hcd_giveback_urb(urb);
1785 		bh->completing_ep = NULL;
1786 	}
1787 
1788 	/* check if there are new URBs to giveback */
1789 	spin_lock_irq(&bh->lock);
1790 	if (!list_empty(&bh->head))
1791 		goto restart;
1792 	bh->running = false;
1793 	spin_unlock_irq(&bh->lock);
1794 }
1795 
1796 /**
1797  * usb_hcd_giveback_urb - return URB from HCD to device driver
1798  * @hcd: host controller returning the URB
1799  * @urb: urb being returned to the USB device driver.
1800  * @status: completion status code for the URB.
1801  * Context: in_interrupt()
1802  *
1803  * This hands the URB from HCD to its USB device driver, using its
1804  * completion function.  The HCD has freed all per-urb resources
1805  * (and is done using urb->hcpriv).  It also released all HCD locks;
1806  * the device driver won't cause problems if it frees, modifies,
1807  * or resubmits this URB.
1808  *
1809  * If @urb was unlinked, the value of @status will be overridden by
1810  * @urb->unlinked.  Erroneous short transfers are detected in case
1811  * the HCD hasn't checked for them.
1812  */
1813 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1814 {
1815 	struct giveback_urb_bh *bh;
1816 	bool running, high_prio_bh;
1817 
1818 	/* pass status to tasklet via unlinked */
1819 	if (likely(!urb->unlinked))
1820 		urb->unlinked = status;
1821 
1822 	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1823 		__usb_hcd_giveback_urb(urb);
1824 		return;
1825 	}
1826 
1827 	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
1828 		bh = &hcd->high_prio_bh;
1829 		high_prio_bh = true;
1830 	} else {
1831 		bh = &hcd->low_prio_bh;
1832 		high_prio_bh = false;
1833 	}
1834 
1835 	spin_lock(&bh->lock);
1836 	list_add_tail(&urb->urb_list, &bh->head);
1837 	running = bh->running;
1838 	spin_unlock(&bh->lock);
1839 
1840 	if (running)
1841 		;
1842 	else if (high_prio_bh)
1843 		tasklet_hi_schedule(&bh->bh);
1844 	else
1845 		tasklet_schedule(&bh->bh);
1846 }
1847 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1848 
1849 /*-------------------------------------------------------------------------*/
1850 
1851 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1852  * queue to drain completely.  The caller must first insure that no more
1853  * URBs can be submitted for this endpoint.
1854  */
1855 void usb_hcd_flush_endpoint(struct usb_device *udev,
1856 		struct usb_host_endpoint *ep)
1857 {
1858 	struct usb_hcd		*hcd;
1859 	struct urb		*urb;
1860 
1861 	if (!ep)
1862 		return;
1863 	might_sleep();
1864 	hcd = bus_to_hcd(udev->bus);
1865 
1866 	/* No more submits can occur */
1867 	spin_lock_irq(&hcd_urb_list_lock);
1868 rescan:
1869 	list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) {
1870 		int	is_in;
1871 
1872 		if (urb->unlinked)
1873 			continue;
1874 		usb_get_urb (urb);
1875 		is_in = usb_urb_dir_in(urb);
1876 		spin_unlock(&hcd_urb_list_lock);
1877 
1878 		/* kick hcd */
1879 		unlink1(hcd, urb, -ESHUTDOWN);
1880 		dev_dbg (hcd->self.controller,
1881 			"shutdown urb %pK ep%d%s-%s\n",
1882 			urb, usb_endpoint_num(&ep->desc),
1883 			is_in ? "in" : "out",
1884 			usb_ep_type_string(usb_endpoint_type(&ep->desc)));
1885 		usb_put_urb (urb);
1886 
1887 		/* list contents may have changed */
1888 		spin_lock(&hcd_urb_list_lock);
1889 		goto rescan;
1890 	}
1891 	spin_unlock_irq(&hcd_urb_list_lock);
1892 
1893 	/* Wait until the endpoint queue is completely empty */
1894 	while (!list_empty (&ep->urb_list)) {
1895 		spin_lock_irq(&hcd_urb_list_lock);
1896 
1897 		/* The list may have changed while we acquired the spinlock */
1898 		urb = NULL;
1899 		if (!list_empty (&ep->urb_list)) {
1900 			urb = list_entry (ep->urb_list.prev, struct urb,
1901 					urb_list);
1902 			usb_get_urb (urb);
1903 		}
1904 		spin_unlock_irq(&hcd_urb_list_lock);
1905 
1906 		if (urb) {
1907 			usb_kill_urb (urb);
1908 			usb_put_urb (urb);
1909 		}
1910 	}
1911 }
1912 
1913 /**
1914  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1915  *				the bus bandwidth
1916  * @udev: target &usb_device
1917  * @new_config: new configuration to install
1918  * @cur_alt: the current alternate interface setting
1919  * @new_alt: alternate interface setting that is being installed
1920  *
1921  * To change configurations, pass in the new configuration in new_config,
1922  * and pass NULL for cur_alt and new_alt.
1923  *
1924  * To reset a device's configuration (put the device in the ADDRESSED state),
1925  * pass in NULL for new_config, cur_alt, and new_alt.
1926  *
1927  * To change alternate interface settings, pass in NULL for new_config,
1928  * pass in the current alternate interface setting in cur_alt,
1929  * and pass in the new alternate interface setting in new_alt.
1930  *
1931  * Return: An error if the requested bandwidth change exceeds the
1932  * bus bandwidth or host controller internal resources.
1933  */
1934 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1935 		struct usb_host_config *new_config,
1936 		struct usb_host_interface *cur_alt,
1937 		struct usb_host_interface *new_alt)
1938 {
1939 	int num_intfs, i, j;
1940 	struct usb_host_interface *alt = NULL;
1941 	int ret = 0;
1942 	struct usb_hcd *hcd;
1943 	struct usb_host_endpoint *ep;
1944 
1945 	hcd = bus_to_hcd(udev->bus);
1946 	if (!hcd->driver->check_bandwidth)
1947 		return 0;
1948 
1949 	/* Configuration is being removed - set configuration 0 */
1950 	if (!new_config && !cur_alt) {
1951 		for (i = 1; i < 16; ++i) {
1952 			ep = udev->ep_out[i];
1953 			if (ep)
1954 				hcd->driver->drop_endpoint(hcd, udev, ep);
1955 			ep = udev->ep_in[i];
1956 			if (ep)
1957 				hcd->driver->drop_endpoint(hcd, udev, ep);
1958 		}
1959 		hcd->driver->check_bandwidth(hcd, udev);
1960 		return 0;
1961 	}
1962 	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1963 	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1964 	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1965 	 * ok to exclude it.
1966 	 */
1967 	if (new_config) {
1968 		num_intfs = new_config->desc.bNumInterfaces;
1969 		/* Remove endpoints (except endpoint 0, which is always on the
1970 		 * schedule) from the old config from the schedule
1971 		 */
1972 		for (i = 1; i < 16; ++i) {
1973 			ep = udev->ep_out[i];
1974 			if (ep) {
1975 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1976 				if (ret < 0)
1977 					goto reset;
1978 			}
1979 			ep = udev->ep_in[i];
1980 			if (ep) {
1981 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1982 				if (ret < 0)
1983 					goto reset;
1984 			}
1985 		}
1986 		for (i = 0; i < num_intfs; ++i) {
1987 			struct usb_host_interface *first_alt;
1988 			int iface_num;
1989 
1990 			first_alt = &new_config->intf_cache[i]->altsetting[0];
1991 			iface_num = first_alt->desc.bInterfaceNumber;
1992 			/* Set up endpoints for alternate interface setting 0 */
1993 			alt = usb_find_alt_setting(new_config, iface_num, 0);
1994 			if (!alt)
1995 				/* No alt setting 0? Pick the first setting. */
1996 				alt = first_alt;
1997 
1998 			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1999 				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
2000 				if (ret < 0)
2001 					goto reset;
2002 			}
2003 		}
2004 	}
2005 	if (cur_alt && new_alt) {
2006 		struct usb_interface *iface = usb_ifnum_to_if(udev,
2007 				cur_alt->desc.bInterfaceNumber);
2008 
2009 		if (!iface)
2010 			return -EINVAL;
2011 		if (iface->resetting_device) {
2012 			/*
2013 			 * The USB core just reset the device, so the xHCI host
2014 			 * and the device will think alt setting 0 is installed.
2015 			 * However, the USB core will pass in the alternate
2016 			 * setting installed before the reset as cur_alt.  Dig
2017 			 * out the alternate setting 0 structure, or the first
2018 			 * alternate setting if a broken device doesn't have alt
2019 			 * setting 0.
2020 			 */
2021 			cur_alt = usb_altnum_to_altsetting(iface, 0);
2022 			if (!cur_alt)
2023 				cur_alt = &iface->altsetting[0];
2024 		}
2025 
2026 		/* Drop all the endpoints in the current alt setting */
2027 		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
2028 			ret = hcd->driver->drop_endpoint(hcd, udev,
2029 					&cur_alt->endpoint[i]);
2030 			if (ret < 0)
2031 				goto reset;
2032 		}
2033 		/* Add all the endpoints in the new alt setting */
2034 		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
2035 			ret = hcd->driver->add_endpoint(hcd, udev,
2036 					&new_alt->endpoint[i]);
2037 			if (ret < 0)
2038 				goto reset;
2039 		}
2040 	}
2041 	ret = hcd->driver->check_bandwidth(hcd, udev);
2042 reset:
2043 	if (ret < 0)
2044 		hcd->driver->reset_bandwidth(hcd, udev);
2045 	return ret;
2046 }
2047 
2048 /* Disables the endpoint: synchronizes with the hcd to make sure all
2049  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
2050  * have been called previously.  Use for set_configuration, set_interface,
2051  * driver removal, physical disconnect.
2052  *
2053  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
2054  * type, maxpacket size, toggle, halt status, and scheduling.
2055  */
2056 void usb_hcd_disable_endpoint(struct usb_device *udev,
2057 		struct usb_host_endpoint *ep)
2058 {
2059 	struct usb_hcd		*hcd;
2060 
2061 	might_sleep();
2062 	hcd = bus_to_hcd(udev->bus);
2063 	if (hcd->driver->endpoint_disable)
2064 		hcd->driver->endpoint_disable(hcd, ep);
2065 }
2066 
2067 /**
2068  * usb_hcd_reset_endpoint - reset host endpoint state
2069  * @udev: USB device.
2070  * @ep:   the endpoint to reset.
2071  *
2072  * Resets any host endpoint state such as the toggle bit, sequence
2073  * number and current window.
2074  */
2075 void usb_hcd_reset_endpoint(struct usb_device *udev,
2076 			    struct usb_host_endpoint *ep)
2077 {
2078 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2079 
2080 	if (hcd->driver->endpoint_reset)
2081 		hcd->driver->endpoint_reset(hcd, ep);
2082 	else {
2083 		int epnum = usb_endpoint_num(&ep->desc);
2084 		int is_out = usb_endpoint_dir_out(&ep->desc);
2085 		int is_control = usb_endpoint_xfer_control(&ep->desc);
2086 
2087 		usb_settoggle(udev, epnum, is_out, 0);
2088 		if (is_control)
2089 			usb_settoggle(udev, epnum, !is_out, 0);
2090 	}
2091 }
2092 
2093 /**
2094  * usb_alloc_streams - allocate bulk endpoint stream IDs.
2095  * @interface:		alternate setting that includes all endpoints.
2096  * @eps:		array of endpoints that need streams.
2097  * @num_eps:		number of endpoints in the array.
2098  * @num_streams:	number of streams to allocate.
2099  * @mem_flags:		flags hcd should use to allocate memory.
2100  *
2101  * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
2102  * Drivers may queue multiple transfers to different stream IDs, which may
2103  * complete in a different order than they were queued.
2104  *
2105  * Return: On success, the number of allocated streams. On failure, a negative
2106  * error code.
2107  */
2108 int usb_alloc_streams(struct usb_interface *interface,
2109 		struct usb_host_endpoint **eps, unsigned int num_eps,
2110 		unsigned int num_streams, gfp_t mem_flags)
2111 {
2112 	struct usb_hcd *hcd;
2113 	struct usb_device *dev;
2114 	int i, ret;
2115 
2116 	dev = interface_to_usbdev(interface);
2117 	hcd = bus_to_hcd(dev->bus);
2118 	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2119 		return -EINVAL;
2120 	if (dev->speed < USB_SPEED_SUPER)
2121 		return -EINVAL;
2122 	if (dev->state < USB_STATE_CONFIGURED)
2123 		return -ENODEV;
2124 
2125 	for (i = 0; i < num_eps; i++) {
2126 		/* Streams only apply to bulk endpoints. */
2127 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2128 			return -EINVAL;
2129 		/* Re-alloc is not allowed */
2130 		if (eps[i]->streams)
2131 			return -EINVAL;
2132 	}
2133 
2134 	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2135 			num_streams, mem_flags);
2136 	if (ret < 0)
2137 		return ret;
2138 
2139 	for (i = 0; i < num_eps; i++)
2140 		eps[i]->streams = ret;
2141 
2142 	return ret;
2143 }
2144 EXPORT_SYMBOL_GPL(usb_alloc_streams);
2145 
2146 /**
2147  * usb_free_streams - free bulk endpoint stream IDs.
2148  * @interface:	alternate setting that includes all endpoints.
2149  * @eps:	array of endpoints to remove streams from.
2150  * @num_eps:	number of endpoints in the array.
2151  * @mem_flags:	flags hcd should use to allocate memory.
2152  *
2153  * Reverts a group of bulk endpoints back to not using stream IDs.
2154  * Can fail if we are given bad arguments, or HCD is broken.
2155  *
2156  * Return: 0 on success. On failure, a negative error code.
2157  */
2158 int usb_free_streams(struct usb_interface *interface,
2159 		struct usb_host_endpoint **eps, unsigned int num_eps,
2160 		gfp_t mem_flags)
2161 {
2162 	struct usb_hcd *hcd;
2163 	struct usb_device *dev;
2164 	int i, ret;
2165 
2166 	dev = interface_to_usbdev(interface);
2167 	hcd = bus_to_hcd(dev->bus);
2168 	if (dev->speed < USB_SPEED_SUPER)
2169 		return -EINVAL;
2170 
2171 	/* Double-free is not allowed */
2172 	for (i = 0; i < num_eps; i++)
2173 		if (!eps[i] || !eps[i]->streams)
2174 			return -EINVAL;
2175 
2176 	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2177 	if (ret < 0)
2178 		return ret;
2179 
2180 	for (i = 0; i < num_eps; i++)
2181 		eps[i]->streams = 0;
2182 
2183 	return ret;
2184 }
2185 EXPORT_SYMBOL_GPL(usb_free_streams);
2186 
2187 /* Protect against drivers that try to unlink URBs after the device
2188  * is gone, by waiting until all unlinks for @udev are finished.
2189  * Since we don't currently track URBs by device, simply wait until
2190  * nothing is running in the locked region of usb_hcd_unlink_urb().
2191  */
2192 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2193 {
2194 	spin_lock_irq(&hcd_urb_unlink_lock);
2195 	spin_unlock_irq(&hcd_urb_unlink_lock);
2196 }
2197 
2198 /*-------------------------------------------------------------------------*/
2199 
2200 /* called in any context */
2201 int usb_hcd_get_frame_number (struct usb_device *udev)
2202 {
2203 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
2204 
2205 	if (!HCD_RH_RUNNING(hcd))
2206 		return -ESHUTDOWN;
2207 	return hcd->driver->get_frame_number (hcd);
2208 }
2209 
2210 /*-------------------------------------------------------------------------*/
2211 
2212 #ifdef	CONFIG_PM
2213 
2214 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2215 {
2216 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2217 	int		status;
2218 	int		old_state = hcd->state;
2219 
2220 	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2221 			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2222 			rhdev->do_remote_wakeup);
2223 	if (HCD_DEAD(hcd)) {
2224 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2225 		return 0;
2226 	}
2227 
2228 	if (!hcd->driver->bus_suspend) {
2229 		status = -ENOENT;
2230 	} else {
2231 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2232 		hcd->state = HC_STATE_QUIESCING;
2233 		status = hcd->driver->bus_suspend(hcd);
2234 	}
2235 	if (status == 0) {
2236 		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2237 		hcd->state = HC_STATE_SUSPENDED;
2238 
2239 		if (!PMSG_IS_AUTO(msg))
2240 			usb_phy_roothub_suspend(hcd->self.sysdev,
2241 						hcd->phy_roothub);
2242 
2243 		/* Did we race with a root-hub wakeup event? */
2244 		if (rhdev->do_remote_wakeup) {
2245 			char	buffer[6];
2246 
2247 			status = hcd->driver->hub_status_data(hcd, buffer);
2248 			if (status != 0) {
2249 				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2250 				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2251 				status = -EBUSY;
2252 			}
2253 		}
2254 	} else {
2255 		spin_lock_irq(&hcd_root_hub_lock);
2256 		if (!HCD_DEAD(hcd)) {
2257 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2258 			hcd->state = old_state;
2259 		}
2260 		spin_unlock_irq(&hcd_root_hub_lock);
2261 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2262 				"suspend", status);
2263 	}
2264 	return status;
2265 }
2266 
2267 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2268 {
2269 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2270 	int		status;
2271 	int		old_state = hcd->state;
2272 
2273 	dev_dbg(&rhdev->dev, "usb %sresume\n",
2274 			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2275 	if (HCD_DEAD(hcd)) {
2276 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2277 		return 0;
2278 	}
2279 
2280 	if (!PMSG_IS_AUTO(msg)) {
2281 		status = usb_phy_roothub_resume(hcd->self.sysdev,
2282 						hcd->phy_roothub);
2283 		if (status)
2284 			return status;
2285 	}
2286 
2287 	if (!hcd->driver->bus_resume)
2288 		return -ENOENT;
2289 	if (HCD_RH_RUNNING(hcd))
2290 		return 0;
2291 
2292 	hcd->state = HC_STATE_RESUMING;
2293 	status = hcd->driver->bus_resume(hcd);
2294 	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2295 	if (status == 0) {
2296 		struct usb_device *udev;
2297 		int port1;
2298 
2299 		spin_lock_irq(&hcd_root_hub_lock);
2300 		if (!HCD_DEAD(hcd)) {
2301 			usb_set_device_state(rhdev, rhdev->actconfig
2302 					? USB_STATE_CONFIGURED
2303 					: USB_STATE_ADDRESS);
2304 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2305 			hcd->state = HC_STATE_RUNNING;
2306 		}
2307 		spin_unlock_irq(&hcd_root_hub_lock);
2308 
2309 		/*
2310 		 * Check whether any of the enabled ports on the root hub are
2311 		 * unsuspended.  If they are then a TRSMRCY delay is needed
2312 		 * (this is what the USB-2 spec calls a "global resume").
2313 		 * Otherwise we can skip the delay.
2314 		 */
2315 		usb_hub_for_each_child(rhdev, port1, udev) {
2316 			if (udev->state != USB_STATE_NOTATTACHED &&
2317 					!udev->port_is_suspended) {
2318 				usleep_range(10000, 11000);	/* TRSMRCY */
2319 				break;
2320 			}
2321 		}
2322 	} else {
2323 		hcd->state = old_state;
2324 		usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub);
2325 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2326 				"resume", status);
2327 		if (status != -ESHUTDOWN)
2328 			usb_hc_died(hcd);
2329 	}
2330 	return status;
2331 }
2332 
2333 /* Workqueue routine for root-hub remote wakeup */
2334 static void hcd_resume_work(struct work_struct *work)
2335 {
2336 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2337 	struct usb_device *udev = hcd->self.root_hub;
2338 
2339 	usb_remote_wakeup(udev);
2340 }
2341 
2342 /**
2343  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2344  * @hcd: host controller for this root hub
2345  *
2346  * The USB host controller calls this function when its root hub is
2347  * suspended (with the remote wakeup feature enabled) and a remote
2348  * wakeup request is received.  The routine submits a workqueue request
2349  * to resume the root hub (that is, manage its downstream ports again).
2350  */
2351 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2352 {
2353 	unsigned long flags;
2354 
2355 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2356 	if (hcd->rh_registered) {
2357 		pm_wakeup_event(&hcd->self.root_hub->dev, 0);
2358 		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2359 		queue_work(pm_wq, &hcd->wakeup_work);
2360 	}
2361 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2362 }
2363 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2364 
2365 #endif	/* CONFIG_PM */
2366 
2367 /*-------------------------------------------------------------------------*/
2368 
2369 #ifdef	CONFIG_USB_OTG
2370 
2371 /**
2372  * usb_bus_start_enum - start immediate enumeration (for OTG)
2373  * @bus: the bus (must use hcd framework)
2374  * @port_num: 1-based number of port; usually bus->otg_port
2375  * Context: in_interrupt()
2376  *
2377  * Starts enumeration, with an immediate reset followed later by
2378  * hub_wq identifying and possibly configuring the device.
2379  * This is needed by OTG controller drivers, where it helps meet
2380  * HNP protocol timing requirements for starting a port reset.
2381  *
2382  * Return: 0 if successful.
2383  */
2384 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2385 {
2386 	struct usb_hcd		*hcd;
2387 	int			status = -EOPNOTSUPP;
2388 
2389 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2390 	 * boards with root hubs hooked up to internal devices (instead of
2391 	 * just the OTG port) may need more attention to resetting...
2392 	 */
2393 	hcd = bus_to_hcd(bus);
2394 	if (port_num && hcd->driver->start_port_reset)
2395 		status = hcd->driver->start_port_reset(hcd, port_num);
2396 
2397 	/* allocate hub_wq shortly after (first) root port reset finishes;
2398 	 * it may issue others, until at least 50 msecs have passed.
2399 	 */
2400 	if (status == 0)
2401 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2402 	return status;
2403 }
2404 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2405 
2406 #endif
2407 
2408 /*-------------------------------------------------------------------------*/
2409 
2410 /**
2411  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2412  * @irq: the IRQ being raised
2413  * @__hcd: pointer to the HCD whose IRQ is being signaled
2414  *
2415  * If the controller isn't HALTed, calls the driver's irq handler.
2416  * Checks whether the controller is now dead.
2417  *
2418  * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2419  */
2420 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2421 {
2422 	struct usb_hcd		*hcd = __hcd;
2423 	irqreturn_t		rc;
2424 
2425 	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2426 		rc = IRQ_NONE;
2427 	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2428 		rc = IRQ_NONE;
2429 	else
2430 		rc = IRQ_HANDLED;
2431 
2432 	return rc;
2433 }
2434 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2435 
2436 /*-------------------------------------------------------------------------*/
2437 
2438 /* Workqueue routine for when the root-hub has died. */
2439 static void hcd_died_work(struct work_struct *work)
2440 {
2441 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, died_work);
2442 	static char *env[] = {
2443 		"ERROR=DEAD",
2444 		NULL
2445 	};
2446 
2447 	/* Notify user space that the host controller has died */
2448 	kobject_uevent_env(&hcd->self.root_hub->dev.kobj, KOBJ_OFFLINE, env);
2449 }
2450 
2451 /**
2452  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2453  * @hcd: pointer to the HCD representing the controller
2454  *
2455  * This is called by bus glue to report a USB host controller that died
2456  * while operations may still have been pending.  It's called automatically
2457  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2458  *
2459  * Only call this function with the primary HCD.
2460  */
2461 void usb_hc_died (struct usb_hcd *hcd)
2462 {
2463 	unsigned long flags;
2464 
2465 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2466 
2467 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2468 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2469 	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2470 	if (hcd->rh_registered) {
2471 		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2472 
2473 		/* make hub_wq clean up old urbs and devices */
2474 		usb_set_device_state (hcd->self.root_hub,
2475 				USB_STATE_NOTATTACHED);
2476 		usb_kick_hub_wq(hcd->self.root_hub);
2477 	}
2478 	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2479 		hcd = hcd->shared_hcd;
2480 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2481 		set_bit(HCD_FLAG_DEAD, &hcd->flags);
2482 		if (hcd->rh_registered) {
2483 			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2484 
2485 			/* make hub_wq clean up old urbs and devices */
2486 			usb_set_device_state(hcd->self.root_hub,
2487 					USB_STATE_NOTATTACHED);
2488 			usb_kick_hub_wq(hcd->self.root_hub);
2489 		}
2490 	}
2491 
2492 	/* Handle the case where this function gets called with a shared HCD */
2493 	if (usb_hcd_is_primary_hcd(hcd))
2494 		schedule_work(&hcd->died_work);
2495 	else
2496 		schedule_work(&hcd->primary_hcd->died_work);
2497 
2498 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2499 	/* Make sure that the other roothub is also deallocated. */
2500 }
2501 EXPORT_SYMBOL_GPL (usb_hc_died);
2502 
2503 /*-------------------------------------------------------------------------*/
2504 
2505 static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2506 {
2507 
2508 	spin_lock_init(&bh->lock);
2509 	INIT_LIST_HEAD(&bh->head);
2510 	tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh);
2511 }
2512 
2513 struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
2514 		struct device *sysdev, struct device *dev, const char *bus_name,
2515 		struct usb_hcd *primary_hcd)
2516 {
2517 	struct usb_hcd *hcd;
2518 
2519 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2520 	if (!hcd)
2521 		return NULL;
2522 	if (primary_hcd == NULL) {
2523 		hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex),
2524 				GFP_KERNEL);
2525 		if (!hcd->address0_mutex) {
2526 			kfree(hcd);
2527 			dev_dbg(dev, "hcd address0 mutex alloc failed\n");
2528 			return NULL;
2529 		}
2530 		mutex_init(hcd->address0_mutex);
2531 		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2532 				GFP_KERNEL);
2533 		if (!hcd->bandwidth_mutex) {
2534 			kfree(hcd->address0_mutex);
2535 			kfree(hcd);
2536 			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2537 			return NULL;
2538 		}
2539 		mutex_init(hcd->bandwidth_mutex);
2540 		dev_set_drvdata(dev, hcd);
2541 	} else {
2542 		mutex_lock(&usb_port_peer_mutex);
2543 		hcd->address0_mutex = primary_hcd->address0_mutex;
2544 		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2545 		hcd->primary_hcd = primary_hcd;
2546 		primary_hcd->primary_hcd = primary_hcd;
2547 		hcd->shared_hcd = primary_hcd;
2548 		primary_hcd->shared_hcd = hcd;
2549 		mutex_unlock(&usb_port_peer_mutex);
2550 	}
2551 
2552 	kref_init(&hcd->kref);
2553 
2554 	usb_bus_init(&hcd->self);
2555 	hcd->self.controller = dev;
2556 	hcd->self.sysdev = sysdev;
2557 	hcd->self.bus_name = bus_name;
2558 	hcd->self.uses_dma = (sysdev->dma_mask != NULL);
2559 
2560 	timer_setup(&hcd->rh_timer, rh_timer_func, 0);
2561 #ifdef CONFIG_PM
2562 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2563 #endif
2564 
2565 	INIT_WORK(&hcd->died_work, hcd_died_work);
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 (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) {
2743 		hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev);
2744 		if (IS_ERR(hcd->phy_roothub))
2745 			return PTR_ERR(hcd->phy_roothub);
2746 
2747 		retval = usb_phy_roothub_init(hcd->phy_roothub);
2748 		if (retval)
2749 			return retval;
2750 
2751 		retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2752 						  PHY_MODE_USB_HOST_SS);
2753 		if (retval)
2754 			retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2755 							  PHY_MODE_USB_HOST);
2756 		if (retval)
2757 			goto err_usb_phy_roothub_power_on;
2758 
2759 		retval = usb_phy_roothub_power_on(hcd->phy_roothub);
2760 		if (retval)
2761 			goto err_usb_phy_roothub_power_on;
2762 	}
2763 
2764 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2765 
2766 	switch (authorized_default) {
2767 	case USB_AUTHORIZE_NONE:
2768 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_NONE;
2769 		break;
2770 
2771 	case USB_AUTHORIZE_ALL:
2772 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_ALL;
2773 		break;
2774 
2775 	case USB_AUTHORIZE_INTERNAL:
2776 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_INTERNAL;
2777 		break;
2778 
2779 	case USB_AUTHORIZE_WIRED:
2780 	default:
2781 		hcd->dev_policy = hcd->wireless ?
2782 			USB_DEVICE_AUTHORIZE_NONE : USB_DEVICE_AUTHORIZE_ALL;
2783 		break;
2784 	}
2785 
2786 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2787 
2788 	/* per default all interfaces are authorized */
2789 	set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
2790 
2791 	/* HC is in reset state, but accessible.  Now do the one-time init,
2792 	 * bottom up so that hcds can customize the root hubs before hub_wq
2793 	 * starts talking to them.  (Note, bus id is assigned early too.)
2794 	 */
2795 	retval = hcd_buffer_create(hcd);
2796 	if (retval != 0) {
2797 		dev_dbg(hcd->self.sysdev, "pool alloc failed\n");
2798 		goto err_create_buf;
2799 	}
2800 
2801 	retval = usb_register_bus(&hcd->self);
2802 	if (retval < 0)
2803 		goto err_register_bus;
2804 
2805 	rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2806 	if (rhdev == NULL) {
2807 		dev_err(hcd->self.sysdev, "unable to allocate root hub\n");
2808 		retval = -ENOMEM;
2809 		goto err_allocate_root_hub;
2810 	}
2811 	mutex_lock(&usb_port_peer_mutex);
2812 	hcd->self.root_hub = rhdev;
2813 	mutex_unlock(&usb_port_peer_mutex);
2814 
2815 	rhdev->rx_lanes = 1;
2816 	rhdev->tx_lanes = 1;
2817 
2818 	switch (hcd->speed) {
2819 	case HCD_USB11:
2820 		rhdev->speed = USB_SPEED_FULL;
2821 		break;
2822 	case HCD_USB2:
2823 		rhdev->speed = USB_SPEED_HIGH;
2824 		break;
2825 	case HCD_USB25:
2826 		rhdev->speed = USB_SPEED_WIRELESS;
2827 		break;
2828 	case HCD_USB3:
2829 		rhdev->speed = USB_SPEED_SUPER;
2830 		break;
2831 	case HCD_USB32:
2832 		rhdev->rx_lanes = 2;
2833 		rhdev->tx_lanes = 2;
2834 		/* fall through */
2835 	case HCD_USB31:
2836 		rhdev->speed = USB_SPEED_SUPER_PLUS;
2837 		break;
2838 	default:
2839 		retval = -EINVAL;
2840 		goto err_set_rh_speed;
2841 	}
2842 
2843 	/* wakeup flag init defaults to "everything works" for root hubs,
2844 	 * but drivers can override it in reset() if needed, along with
2845 	 * recording the overall controller's system wakeup capability.
2846 	 */
2847 	device_set_wakeup_capable(&rhdev->dev, 1);
2848 
2849 	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2850 	 * registered.  But since the controller can die at any time,
2851 	 * let's initialize the flag before touching the hardware.
2852 	 */
2853 	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2854 
2855 	/* "reset" is misnamed; its role is now one-time init. the controller
2856 	 * should already have been reset (and boot firmware kicked off etc).
2857 	 */
2858 	if (hcd->driver->reset) {
2859 		retval = hcd->driver->reset(hcd);
2860 		if (retval < 0) {
2861 			dev_err(hcd->self.controller, "can't setup: %d\n",
2862 					retval);
2863 			goto err_hcd_driver_setup;
2864 		}
2865 	}
2866 	hcd->rh_pollable = 1;
2867 
2868 	/* NOTE: root hub and controller capabilities may not be the same */
2869 	if (device_can_wakeup(hcd->self.controller)
2870 			&& device_can_wakeup(&hcd->self.root_hub->dev))
2871 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2872 
2873 	/* initialize tasklets */
2874 	init_giveback_urb_bh(&hcd->high_prio_bh);
2875 	init_giveback_urb_bh(&hcd->low_prio_bh);
2876 
2877 	/* enable irqs just before we start the controller,
2878 	 * if the BIOS provides legacy PCI irqs.
2879 	 */
2880 	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2881 		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2882 		if (retval)
2883 			goto err_request_irq;
2884 	}
2885 
2886 	hcd->state = HC_STATE_RUNNING;
2887 	retval = hcd->driver->start(hcd);
2888 	if (retval < 0) {
2889 		dev_err(hcd->self.controller, "startup error %d\n", retval);
2890 		goto err_hcd_driver_start;
2891 	}
2892 
2893 	/* starting here, usbcore will pay attention to this root hub */
2894 	retval = register_root_hub(hcd);
2895 	if (retval != 0)
2896 		goto err_register_root_hub;
2897 
2898 	retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2899 	if (retval < 0) {
2900 		printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n",
2901 		       retval);
2902 		goto error_create_attr_group;
2903 	}
2904 	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2905 		usb_hcd_poll_rh_status(hcd);
2906 
2907 	return retval;
2908 
2909 error_create_attr_group:
2910 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2911 	if (HC_IS_RUNNING(hcd->state))
2912 		hcd->state = HC_STATE_QUIESCING;
2913 	spin_lock_irq(&hcd_root_hub_lock);
2914 	hcd->rh_registered = 0;
2915 	spin_unlock_irq(&hcd_root_hub_lock);
2916 
2917 #ifdef CONFIG_PM
2918 	cancel_work_sync(&hcd->wakeup_work);
2919 #endif
2920 	cancel_work_sync(&hcd->died_work);
2921 	mutex_lock(&usb_bus_idr_lock);
2922 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2923 	mutex_unlock(&usb_bus_idr_lock);
2924 err_register_root_hub:
2925 	hcd->rh_pollable = 0;
2926 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2927 	del_timer_sync(&hcd->rh_timer);
2928 	hcd->driver->stop(hcd);
2929 	hcd->state = HC_STATE_HALT;
2930 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2931 	del_timer_sync(&hcd->rh_timer);
2932 err_hcd_driver_start:
2933 	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2934 		free_irq(irqnum, hcd);
2935 err_request_irq:
2936 err_hcd_driver_setup:
2937 err_set_rh_speed:
2938 	usb_put_invalidate_rhdev(hcd);
2939 err_allocate_root_hub:
2940 	usb_deregister_bus(&hcd->self);
2941 err_register_bus:
2942 	hcd_buffer_destroy(hcd);
2943 err_create_buf:
2944 	usb_phy_roothub_power_off(hcd->phy_roothub);
2945 err_usb_phy_roothub_power_on:
2946 	usb_phy_roothub_exit(hcd->phy_roothub);
2947 
2948 	return retval;
2949 }
2950 EXPORT_SYMBOL_GPL(usb_add_hcd);
2951 
2952 /**
2953  * usb_remove_hcd - shutdown processing for generic HCDs
2954  * @hcd: the usb_hcd structure to remove
2955  * Context: !in_interrupt()
2956  *
2957  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2958  * invoking the HCD's stop() method.
2959  */
2960 void usb_remove_hcd(struct usb_hcd *hcd)
2961 {
2962 	struct usb_device *rhdev = hcd->self.root_hub;
2963 
2964 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2965 
2966 	usb_get_dev(rhdev);
2967 	sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2968 
2969 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2970 	if (HC_IS_RUNNING (hcd->state))
2971 		hcd->state = HC_STATE_QUIESCING;
2972 
2973 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2974 	spin_lock_irq (&hcd_root_hub_lock);
2975 	hcd->rh_registered = 0;
2976 	spin_unlock_irq (&hcd_root_hub_lock);
2977 
2978 #ifdef CONFIG_PM
2979 	cancel_work_sync(&hcd->wakeup_work);
2980 #endif
2981 	cancel_work_sync(&hcd->died_work);
2982 
2983 	mutex_lock(&usb_bus_idr_lock);
2984 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2985 	mutex_unlock(&usb_bus_idr_lock);
2986 
2987 	/*
2988 	 * tasklet_kill() isn't needed here because:
2989 	 * - driver's disconnect() called from usb_disconnect() should
2990 	 *   make sure its URBs are completed during the disconnect()
2991 	 *   callback
2992 	 *
2993 	 * - it is too late to run complete() here since driver may have
2994 	 *   been removed already now
2995 	 */
2996 
2997 	/* Prevent any more root-hub status calls from the timer.
2998 	 * The HCD might still restart the timer (if a port status change
2999 	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
3000 	 * the hub_status_data() callback.
3001 	 */
3002 	hcd->rh_pollable = 0;
3003 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
3004 	del_timer_sync(&hcd->rh_timer);
3005 
3006 	hcd->driver->stop(hcd);
3007 	hcd->state = HC_STATE_HALT;
3008 
3009 	/* In case the HCD restarted the timer, stop it again. */
3010 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
3011 	del_timer_sync(&hcd->rh_timer);
3012 
3013 	if (usb_hcd_is_primary_hcd(hcd)) {
3014 		if (hcd->irq > 0)
3015 			free_irq(hcd->irq, hcd);
3016 	}
3017 
3018 	usb_deregister_bus(&hcd->self);
3019 	hcd_buffer_destroy(hcd);
3020 
3021 	usb_phy_roothub_power_off(hcd->phy_roothub);
3022 	usb_phy_roothub_exit(hcd->phy_roothub);
3023 
3024 	usb_put_invalidate_rhdev(hcd);
3025 	hcd->flags = 0;
3026 }
3027 EXPORT_SYMBOL_GPL(usb_remove_hcd);
3028 
3029 void
3030 usb_hcd_platform_shutdown(struct platform_device *dev)
3031 {
3032 	struct usb_hcd *hcd = platform_get_drvdata(dev);
3033 
3034 	/* No need for pm_runtime_put(), we're shutting down */
3035 	pm_runtime_get_sync(&dev->dev);
3036 
3037 	if (hcd->driver->shutdown)
3038 		hcd->driver->shutdown(hcd);
3039 }
3040 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
3041 
3042 /*-------------------------------------------------------------------------*/
3043 
3044 #if IS_ENABLED(CONFIG_USB_MON)
3045 
3046 const struct usb_mon_operations *mon_ops;
3047 
3048 /*
3049  * The registration is unlocked.
3050  * We do it this way because we do not want to lock in hot paths.
3051  *
3052  * Notice that the code is minimally error-proof. Because usbmon needs
3053  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
3054  */
3055 
3056 int usb_mon_register(const struct usb_mon_operations *ops)
3057 {
3058 
3059 	if (mon_ops)
3060 		return -EBUSY;
3061 
3062 	mon_ops = ops;
3063 	mb();
3064 	return 0;
3065 }
3066 EXPORT_SYMBOL_GPL (usb_mon_register);
3067 
3068 void usb_mon_deregister (void)
3069 {
3070 
3071 	if (mon_ops == NULL) {
3072 		printk(KERN_ERR "USB: monitor was not registered\n");
3073 		return;
3074 	}
3075 	mon_ops = NULL;
3076 	mb();
3077 }
3078 EXPORT_SYMBOL_GPL (usb_mon_deregister);
3079 
3080 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
3081