xref: /linux/drivers/usb/core/hcd.c (revision d1e280334b7f0a1df441e08bd1f6a1bcc36b3bbb)
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 <linux/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 #include <linux/genalloc.h>
33 #include <linux/io.h>
34 #include <linux/kcov.h>
35 
36 #include <linux/phy/phy.h>
37 #include <linux/usb.h>
38 #include <linux/usb/hcd.h>
39 #include <linux/usb/otg.h>
40 
41 #include "usb.h"
42 #include "phy.h"
43 
44 
45 /*-------------------------------------------------------------------------*/
46 
47 /*
48  * USB Host Controller Driver framework
49  *
50  * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
51  * HCD-specific behaviors/bugs.
52  *
53  * This does error checks, tracks devices and urbs, and delegates to a
54  * "hc_driver" only for code (and data) that really needs to know about
55  * hardware differences.  That includes root hub registers, i/o queues,
56  * and so on ... but as little else as possible.
57  *
58  * Shared code includes most of the "root hub" code (these are emulated,
59  * though each HC's hardware works differently) and PCI glue, plus request
60  * tracking overhead.  The HCD code should only block on spinlocks or on
61  * hardware handshaking; blocking on software events (such as other kernel
62  * threads releasing resources, or completing actions) is all generic.
63  *
64  * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
65  * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
66  * only by the hub driver ... and that neither should be seen or used by
67  * usb client device drivers.
68  *
69  * Contributors of ideas or unattributed patches include: David Brownell,
70  * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
71  *
72  * HISTORY:
73  * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
74  *		associated cleanup.  "usb_hcd" still != "usb_bus".
75  * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
76  */
77 
78 /*-------------------------------------------------------------------------*/
79 
80 /* host controllers we manage */
81 DEFINE_IDR (usb_bus_idr);
82 EXPORT_SYMBOL_GPL (usb_bus_idr);
83 
84 /* used when allocating bus numbers */
85 #define USB_MAXBUS		64
86 
87 /* used when updating list of hcds */
88 DEFINE_MUTEX(usb_bus_idr_lock);	/* exported only for usbfs */
89 EXPORT_SYMBOL_GPL (usb_bus_idr_lock);
90 
91 /* used for controlling access to virtual root hubs */
92 static DEFINE_SPINLOCK(hcd_root_hub_lock);
93 
94 /* used when updating an endpoint's URB list */
95 static DEFINE_SPINLOCK(hcd_urb_list_lock);
96 
97 /* used to protect against unlinking URBs after the device is gone */
98 static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
99 
100 /* wait queue for synchronous unlinks */
101 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
102 
103 /*-------------------------------------------------------------------------*/
104 
105 /*
106  * Sharable chunks of root hub code.
107  */
108 
109 /*-------------------------------------------------------------------------*/
110 #define KERNEL_REL	bin2bcd(LINUX_VERSION_MAJOR)
111 #define KERNEL_VER	bin2bcd(LINUX_VERSION_PATCHLEVEL)
112 
113 /* usb 3.1 root hub device descriptor */
114 static const u8 usb31_rh_dev_descriptor[18] = {
115 	0x12,       /*  __u8  bLength; */
116 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
117 	0x10, 0x03, /*  __le16 bcdUSB; v3.1 */
118 
119 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
120 	0x00,	    /*  __u8  bDeviceSubClass; */
121 	0x03,       /*  __u8  bDeviceProtocol; USB 3 hub */
122 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
123 
124 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
125 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
126 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
127 
128 	0x03,       /*  __u8  iManufacturer; */
129 	0x02,       /*  __u8  iProduct; */
130 	0x01,       /*  __u8  iSerialNumber; */
131 	0x01        /*  __u8  bNumConfigurations; */
132 };
133 
134 /* usb 3.0 root hub device descriptor */
135 static const u8 usb3_rh_dev_descriptor[18] = {
136 	0x12,       /*  __u8  bLength; */
137 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
138 	0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
139 
140 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
141 	0x00,	    /*  __u8  bDeviceSubClass; */
142 	0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
143 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
144 
145 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
146 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
147 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
148 
149 	0x03,       /*  __u8  iManufacturer; */
150 	0x02,       /*  __u8  iProduct; */
151 	0x01,       /*  __u8  iSerialNumber; */
152 	0x01        /*  __u8  bNumConfigurations; */
153 };
154 
155 /* usb 2.0 root hub device descriptor */
156 static const u8 usb2_rh_dev_descriptor[18] = {
157 	0x12,       /*  __u8  bLength; */
158 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
159 	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
160 
161 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
162 	0x00,	    /*  __u8  bDeviceSubClass; */
163 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
164 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
165 
166 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
167 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
168 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
169 
170 	0x03,       /*  __u8  iManufacturer; */
171 	0x02,       /*  __u8  iProduct; */
172 	0x01,       /*  __u8  iSerialNumber; */
173 	0x01        /*  __u8  bNumConfigurations; */
174 };
175 
176 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
177 
178 /* usb 1.1 root hub device descriptor */
179 static const u8 usb11_rh_dev_descriptor[18] = {
180 	0x12,       /*  __u8  bLength; */
181 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
182 	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
183 
184 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
185 	0x00,	    /*  __u8  bDeviceSubClass; */
186 	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
187 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
188 
189 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
190 	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
191 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
192 
193 	0x03,       /*  __u8  iManufacturer; */
194 	0x02,       /*  __u8  iProduct; */
195 	0x01,       /*  __u8  iSerialNumber; */
196 	0x01        /*  __u8  bNumConfigurations; */
197 };
198 
199 
200 /*-------------------------------------------------------------------------*/
201 
202 /* Configuration descriptors for our root hubs */
203 
204 static const u8 fs_rh_config_descriptor[] = {
205 
206 	/* one configuration */
207 	0x09,       /*  __u8  bLength; */
208 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
209 	0x19, 0x00, /*  __le16 wTotalLength; */
210 	0x01,       /*  __u8  bNumInterfaces; (1) */
211 	0x01,       /*  __u8  bConfigurationValue; */
212 	0x00,       /*  __u8  iConfiguration; */
213 	0xc0,       /*  __u8  bmAttributes;
214 				 Bit 7: must be set,
215 				     6: Self-powered,
216 				     5: Remote wakeup,
217 				     4..0: resvd */
218 	0x00,       /*  __u8  MaxPower; */
219 
220 	/* USB 1.1:
221 	 * USB 2.0, single TT organization (mandatory):
222 	 *	one interface, protocol 0
223 	 *
224 	 * USB 2.0, multiple TT organization (optional):
225 	 *	two interfaces, protocols 1 (like single TT)
226 	 *	and 2 (multiple TT mode) ... config is
227 	 *	sometimes settable
228 	 *	NOT IMPLEMENTED
229 	 */
230 
231 	/* one interface */
232 	0x09,       /*  __u8  if_bLength; */
233 	USB_DT_INTERFACE,  /* __u8 if_bDescriptorType; Interface */
234 	0x00,       /*  __u8  if_bInterfaceNumber; */
235 	0x00,       /*  __u8  if_bAlternateSetting; */
236 	0x01,       /*  __u8  if_bNumEndpoints; */
237 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
238 	0x00,       /*  __u8  if_bInterfaceSubClass; */
239 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
240 	0x00,       /*  __u8  if_iInterface; */
241 
242 	/* one endpoint (status change endpoint) */
243 	0x07,       /*  __u8  ep_bLength; */
244 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
245 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
246 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
247 	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
248 	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
249 };
250 
251 static const u8 hs_rh_config_descriptor[] = {
252 
253 	/* one configuration */
254 	0x09,       /*  __u8  bLength; */
255 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
256 	0x19, 0x00, /*  __le16 wTotalLength; */
257 	0x01,       /*  __u8  bNumInterfaces; (1) */
258 	0x01,       /*  __u8  bConfigurationValue; */
259 	0x00,       /*  __u8  iConfiguration; */
260 	0xc0,       /*  __u8  bmAttributes;
261 				 Bit 7: must be set,
262 				     6: Self-powered,
263 				     5: Remote wakeup,
264 				     4..0: resvd */
265 	0x00,       /*  __u8  MaxPower; */
266 
267 	/* USB 1.1:
268 	 * USB 2.0, single TT organization (mandatory):
269 	 *	one interface, protocol 0
270 	 *
271 	 * USB 2.0, multiple TT organization (optional):
272 	 *	two interfaces, protocols 1 (like single TT)
273 	 *	and 2 (multiple TT mode) ... config is
274 	 *	sometimes settable
275 	 *	NOT IMPLEMENTED
276 	 */
277 
278 	/* one interface */
279 	0x09,       /*  __u8  if_bLength; */
280 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
281 	0x00,       /*  __u8  if_bInterfaceNumber; */
282 	0x00,       /*  __u8  if_bAlternateSetting; */
283 	0x01,       /*  __u8  if_bNumEndpoints; */
284 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
285 	0x00,       /*  __u8  if_bInterfaceSubClass; */
286 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
287 	0x00,       /*  __u8  if_iInterface; */
288 
289 	/* one endpoint (status change endpoint) */
290 	0x07,       /*  __u8  ep_bLength; */
291 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
292 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
293 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
294 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
295 		     * see hub.c:hub_configure() for details. */
296 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
297 	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
298 };
299 
300 static const u8 ss_rh_config_descriptor[] = {
301 	/* one configuration */
302 	0x09,       /*  __u8  bLength; */
303 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
304 	0x1f, 0x00, /*  __le16 wTotalLength; */
305 	0x01,       /*  __u8  bNumInterfaces; (1) */
306 	0x01,       /*  __u8  bConfigurationValue; */
307 	0x00,       /*  __u8  iConfiguration; */
308 	0xc0,       /*  __u8  bmAttributes;
309 				 Bit 7: must be set,
310 				     6: Self-powered,
311 				     5: Remote wakeup,
312 				     4..0: resvd */
313 	0x00,       /*  __u8  MaxPower; */
314 
315 	/* one interface */
316 	0x09,       /*  __u8  if_bLength; */
317 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
318 	0x00,       /*  __u8  if_bInterfaceNumber; */
319 	0x00,       /*  __u8  if_bAlternateSetting; */
320 	0x01,       /*  __u8  if_bNumEndpoints; */
321 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
322 	0x00,       /*  __u8  if_bInterfaceSubClass; */
323 	0x00,       /*  __u8  if_bInterfaceProtocol; */
324 	0x00,       /*  __u8  if_iInterface; */
325 
326 	/* one endpoint (status change endpoint) */
327 	0x07,       /*  __u8  ep_bLength; */
328 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
329 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
330 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
331 	0x02, 0x00, /* __le16 ep_wMaxPacketSize; 2 bytes per USB3 10.15.1 */
332 	0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
333 
334 	/* one SuperSpeed endpoint companion descriptor */
335 	0x06,        /* __u8 ss_bLength */
336 	USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */
337 		     /* Companion */
338 	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
339 	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
340 	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
341 };
342 
343 /* authorized_default behaviour:
344  * -1 is authorized for all devices (leftover from wireless USB)
345  * 0 is unauthorized for all devices
346  * 1 is authorized for all devices
347  * 2 is authorized for internal devices
348  */
349 #define USB_AUTHORIZE_WIRED	-1
350 #define USB_AUTHORIZE_NONE	0
351 #define USB_AUTHORIZE_ALL	1
352 #define USB_AUTHORIZE_INTERNAL	2
353 
354 static int authorized_default = CONFIG_USB_DEFAULT_AUTHORIZATION_MODE;
355 module_param(authorized_default, int, S_IRUGO|S_IWUSR);
356 MODULE_PARM_DESC(authorized_default,
357 		"Default USB device authorization: 0 is not authorized, 1 is authorized (default), 2 is authorized for internal devices, -1 is authorized (same as 1)");
358 /*-------------------------------------------------------------------------*/
359 
360 /**
361  * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
362  * @s: Null-terminated ASCII (actually ISO-8859-1) string
363  * @buf: Buffer for USB string descriptor (header + UTF-16LE)
364  * @len: Length (in bytes; may be odd) of descriptor buffer.
365  *
366  * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
367  * whichever is less.
368  *
369  * Note:
370  * USB String descriptors can contain at most 126 characters; input
371  * strings longer than that are truncated.
372  */
373 static unsigned
374 ascii2desc(char const *s, u8 *buf, unsigned len)
375 {
376 	unsigned n, t = 2 + 2*strlen(s);
377 
378 	if (t > 254)
379 		t = 254;	/* Longest possible UTF string descriptor */
380 	if (len > t)
381 		len = t;
382 
383 	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
384 
385 	n = len;
386 	while (n--) {
387 		*buf++ = t;
388 		if (!n--)
389 			break;
390 		*buf++ = t >> 8;
391 		t = (unsigned char)*s++;
392 	}
393 	return len;
394 }
395 
396 /**
397  * rh_string() - provides string descriptors for root hub
398  * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
399  * @hcd: the host controller for this root hub
400  * @data: buffer for output packet
401  * @len: length of the provided buffer
402  *
403  * Produces either a manufacturer, product or serial number string for the
404  * virtual root hub device.
405  *
406  * Return: The number of bytes filled in: the length of the descriptor or
407  * of the provided buffer, whichever is less.
408  */
409 static unsigned
410 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
411 {
412 	char buf[160];
413 	char const *s;
414 	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
415 
416 	/* language ids */
417 	switch (id) {
418 	case 0:
419 		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
420 		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
421 		if (len > 4)
422 			len = 4;
423 		memcpy(data, langids, len);
424 		return len;
425 	case 1:
426 		/* Serial number */
427 		s = hcd->self.bus_name;
428 		break;
429 	case 2:
430 		/* Product name */
431 		s = hcd->product_desc;
432 		break;
433 	case 3:
434 		/* Manufacturer */
435 		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
436 			init_utsname()->release, hcd->driver->description);
437 		s = buf;
438 		break;
439 	default:
440 		/* Can't happen; caller guarantees it */
441 		return 0;
442 	}
443 
444 	return ascii2desc(s, data, len);
445 }
446 
447 
448 /* Root hub control transfers execute synchronously */
449 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
450 {
451 	struct usb_ctrlrequest *cmd;
452 	u16		typeReq, wValue, wIndex, wLength;
453 	u8		*ubuf = urb->transfer_buffer;
454 	unsigned	len = 0;
455 	int		status;
456 	u8		patch_wakeup = 0;
457 	u8		patch_protocol = 0;
458 	u16		tbuf_size;
459 	u8		*tbuf = NULL;
460 	const u8	*bufp;
461 
462 	might_sleep();
463 
464 	spin_lock_irq(&hcd_root_hub_lock);
465 	status = usb_hcd_link_urb_to_ep(hcd, urb);
466 	spin_unlock_irq(&hcd_root_hub_lock);
467 	if (status)
468 		return status;
469 	urb->hcpriv = hcd;	/* Indicate it's queued */
470 
471 	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
472 	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
473 	wValue   = le16_to_cpu (cmd->wValue);
474 	wIndex   = le16_to_cpu (cmd->wIndex);
475 	wLength  = le16_to_cpu (cmd->wLength);
476 
477 	if (wLength > urb->transfer_buffer_length)
478 		goto error;
479 
480 	/*
481 	 * tbuf should be at least as big as the
482 	 * USB hub descriptor.
483 	 */
484 	tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
485 	tbuf = kzalloc(tbuf_size, GFP_KERNEL);
486 	if (!tbuf) {
487 		status = -ENOMEM;
488 		goto err_alloc;
489 	}
490 
491 	bufp = tbuf;
492 
493 
494 	urb->actual_length = 0;
495 	switch (typeReq) {
496 
497 	/* DEVICE REQUESTS */
498 
499 	/* The root hub's remote wakeup enable bit is implemented using
500 	 * driver model wakeup flags.  If this system supports wakeup
501 	 * through USB, userspace may change the default "allow wakeup"
502 	 * policy through sysfs or these calls.
503 	 *
504 	 * Most root hubs support wakeup from downstream devices, for
505 	 * runtime power management (disabling USB clocks and reducing
506 	 * VBUS power usage).  However, not all of them do so; silicon,
507 	 * board, and BIOS bugs here are not uncommon, so these can't
508 	 * be treated quite like external hubs.
509 	 *
510 	 * Likewise, not all root hubs will pass wakeup events upstream,
511 	 * to wake up the whole system.  So don't assume root hub and
512 	 * controller capabilities are identical.
513 	 */
514 
515 	case DeviceRequest | USB_REQ_GET_STATUS:
516 		tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
517 					<< USB_DEVICE_REMOTE_WAKEUP)
518 				| (1 << USB_DEVICE_SELF_POWERED);
519 		tbuf[1] = 0;
520 		len = 2;
521 		break;
522 	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
523 		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
524 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
525 		else
526 			goto error;
527 		break;
528 	case DeviceOutRequest | USB_REQ_SET_FEATURE:
529 		if (device_can_wakeup(&hcd->self.root_hub->dev)
530 				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
531 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
532 		else
533 			goto error;
534 		break;
535 	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
536 		tbuf[0] = 1;
537 		len = 1;
538 		fallthrough;
539 	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
540 		break;
541 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
542 		switch (wValue & 0xff00) {
543 		case USB_DT_DEVICE << 8:
544 			switch (hcd->speed) {
545 			case HCD_USB32:
546 			case HCD_USB31:
547 				bufp = usb31_rh_dev_descriptor;
548 				break;
549 			case HCD_USB3:
550 				bufp = usb3_rh_dev_descriptor;
551 				break;
552 			case HCD_USB2:
553 				bufp = usb2_rh_dev_descriptor;
554 				break;
555 			case HCD_USB11:
556 				bufp = usb11_rh_dev_descriptor;
557 				break;
558 			default:
559 				goto error;
560 			}
561 			len = 18;
562 			if (hcd->has_tt)
563 				patch_protocol = 1;
564 			break;
565 		case USB_DT_CONFIG << 8:
566 			switch (hcd->speed) {
567 			case HCD_USB32:
568 			case HCD_USB31:
569 			case HCD_USB3:
570 				bufp = ss_rh_config_descriptor;
571 				len = sizeof ss_rh_config_descriptor;
572 				break;
573 			case HCD_USB2:
574 				bufp = hs_rh_config_descriptor;
575 				len = sizeof hs_rh_config_descriptor;
576 				break;
577 			case HCD_USB11:
578 				bufp = fs_rh_config_descriptor;
579 				len = sizeof fs_rh_config_descriptor;
580 				break;
581 			default:
582 				goto error;
583 			}
584 			if (device_can_wakeup(&hcd->self.root_hub->dev))
585 				patch_wakeup = 1;
586 			break;
587 		case USB_DT_STRING << 8:
588 			if ((wValue & 0xff) < 4)
589 				urb->actual_length = rh_string(wValue & 0xff,
590 						hcd, ubuf, wLength);
591 			else /* unsupported IDs --> "protocol stall" */
592 				goto error;
593 			break;
594 		case USB_DT_BOS << 8:
595 			goto nongeneric;
596 		default:
597 			goto error;
598 		}
599 		break;
600 	case DeviceRequest | USB_REQ_GET_INTERFACE:
601 		tbuf[0] = 0;
602 		len = 1;
603 		fallthrough;
604 	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
605 		break;
606 	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
607 		/* wValue == urb->dev->devaddr */
608 		dev_dbg (hcd->self.controller, "root hub device address %d\n",
609 			wValue);
610 		break;
611 
612 	/* INTERFACE REQUESTS (no defined feature/status flags) */
613 
614 	/* ENDPOINT REQUESTS */
615 
616 	case EndpointRequest | USB_REQ_GET_STATUS:
617 		/* ENDPOINT_HALT flag */
618 		tbuf[0] = 0;
619 		tbuf[1] = 0;
620 		len = 2;
621 		fallthrough;
622 	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
623 	case EndpointOutRequest | USB_REQ_SET_FEATURE:
624 		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
625 		break;
626 
627 	/* CLASS REQUESTS (and errors) */
628 
629 	default:
630 nongeneric:
631 		/* non-generic request */
632 		switch (typeReq) {
633 		case GetHubStatus:
634 			len = 4;
635 			break;
636 		case GetPortStatus:
637 			if (wValue == HUB_PORT_STATUS)
638 				len = 4;
639 			else
640 				/* other port status types return 8 bytes */
641 				len = 8;
642 			break;
643 		case GetHubDescriptor:
644 			len = sizeof (struct usb_hub_descriptor);
645 			break;
646 		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
647 			/* len is returned by hub_control */
648 			break;
649 		}
650 		status = hcd->driver->hub_control (hcd,
651 			typeReq, wValue, wIndex,
652 			tbuf, wLength);
653 
654 		if (typeReq == GetHubDescriptor)
655 			usb_hub_adjust_deviceremovable(hcd->self.root_hub,
656 				(struct usb_hub_descriptor *)tbuf);
657 		break;
658 error:
659 		/* "protocol stall" on error */
660 		status = -EPIPE;
661 	}
662 
663 	if (status < 0) {
664 		len = 0;
665 		if (status != -EPIPE) {
666 			dev_dbg (hcd->self.controller,
667 				"CTRL: TypeReq=0x%x val=0x%x "
668 				"idx=0x%x len=%d ==> %d\n",
669 				typeReq, wValue, wIndex,
670 				wLength, status);
671 		}
672 	} else if (status > 0) {
673 		/* hub_control may return the length of data copied. */
674 		len = status;
675 		status = 0;
676 	}
677 	if (len) {
678 		if (urb->transfer_buffer_length < len)
679 			len = urb->transfer_buffer_length;
680 		urb->actual_length = len;
681 		/* always USB_DIR_IN, toward host */
682 		memcpy (ubuf, bufp, len);
683 
684 		/* report whether RH hardware supports remote wakeup */
685 		if (patch_wakeup &&
686 				len > offsetof (struct usb_config_descriptor,
687 						bmAttributes))
688 			((struct usb_config_descriptor *)ubuf)->bmAttributes
689 				|= USB_CONFIG_ATT_WAKEUP;
690 
691 		/* report whether RH hardware has an integrated TT */
692 		if (patch_protocol &&
693 				len > offsetof(struct usb_device_descriptor,
694 						bDeviceProtocol))
695 			((struct usb_device_descriptor *) ubuf)->
696 				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
697 	}
698 
699 	kfree(tbuf);
700  err_alloc:
701 
702 	/* any errors get returned through the urb completion */
703 	spin_lock_irq(&hcd_root_hub_lock);
704 	usb_hcd_unlink_urb_from_ep(hcd, urb);
705 	usb_hcd_giveback_urb(hcd, urb, status);
706 	spin_unlock_irq(&hcd_root_hub_lock);
707 	return 0;
708 }
709 
710 /*-------------------------------------------------------------------------*/
711 
712 /*
713  * Root Hub interrupt transfers are polled using a timer if the
714  * driver requests it; otherwise the driver is responsible for
715  * calling usb_hcd_poll_rh_status() when an event occurs.
716  *
717  * Completion handler may not sleep. See usb_hcd_giveback_urb() for details.
718  */
719 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
720 {
721 	struct urb	*urb;
722 	int		length;
723 	int		status;
724 	unsigned long	flags;
725 	char		buffer[6];	/* Any root hubs with > 31 ports? */
726 
727 	if (unlikely(!hcd->rh_pollable))
728 		return;
729 	if (!hcd->uses_new_polling && !hcd->status_urb)
730 		return;
731 
732 	length = hcd->driver->hub_status_data(hcd, buffer);
733 	if (length > 0) {
734 
735 		/* try to complete the status urb */
736 		spin_lock_irqsave(&hcd_root_hub_lock, flags);
737 		urb = hcd->status_urb;
738 		if (urb) {
739 			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
740 			hcd->status_urb = NULL;
741 			if (urb->transfer_buffer_length >= length) {
742 				status = 0;
743 			} else {
744 				status = -EOVERFLOW;
745 				length = urb->transfer_buffer_length;
746 			}
747 			urb->actual_length = length;
748 			memcpy(urb->transfer_buffer, buffer, length);
749 
750 			usb_hcd_unlink_urb_from_ep(hcd, urb);
751 			usb_hcd_giveback_urb(hcd, urb, status);
752 		} else {
753 			length = 0;
754 			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
755 		}
756 		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
757 	}
758 
759 	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
760 	 * exceed that limit if HZ is 100. The math is more clunky than
761 	 * maybe expected, this is to make sure that all timers for USB devices
762 	 * fire at the same time to give the CPU a break in between */
763 	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
764 			(length == 0 && hcd->status_urb != NULL))
765 		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
766 }
767 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
768 
769 /* timer callback */
770 static void rh_timer_func (struct timer_list *t)
771 {
772 	struct usb_hcd *_hcd = timer_container_of(_hcd, t, rh_timer);
773 
774 	usb_hcd_poll_rh_status(_hcd);
775 }
776 
777 /*-------------------------------------------------------------------------*/
778 
779 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
780 {
781 	int		retval;
782 	unsigned long	flags;
783 	unsigned	len = 1 + (urb->dev->maxchild / 8);
784 
785 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
786 	if (hcd->status_urb || urb->transfer_buffer_length < len) {
787 		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
788 		retval = -EINVAL;
789 		goto done;
790 	}
791 
792 	retval = usb_hcd_link_urb_to_ep(hcd, urb);
793 	if (retval)
794 		goto done;
795 
796 	hcd->status_urb = urb;
797 	urb->hcpriv = hcd;	/* indicate it's queued */
798 	if (!hcd->uses_new_polling)
799 		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
800 
801 	/* If a status change has already occurred, report it ASAP */
802 	else if (HCD_POLL_PENDING(hcd))
803 		mod_timer(&hcd->rh_timer, jiffies);
804 	retval = 0;
805  done:
806 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
807 	return retval;
808 }
809 
810 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
811 {
812 	if (usb_endpoint_xfer_int(&urb->ep->desc))
813 		return rh_queue_status (hcd, urb);
814 	if (usb_endpoint_xfer_control(&urb->ep->desc))
815 		return rh_call_control (hcd, urb);
816 	return -EINVAL;
817 }
818 
819 /*-------------------------------------------------------------------------*/
820 
821 /* Unlinks of root-hub control URBs are legal, but they don't do anything
822  * since these URBs always execute synchronously.
823  */
824 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
825 {
826 	unsigned long	flags;
827 	int		rc;
828 
829 	spin_lock_irqsave(&hcd_root_hub_lock, flags);
830 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
831 	if (rc)
832 		goto done;
833 
834 	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
835 		;	/* Do nothing */
836 
837 	} else {				/* Status URB */
838 		if (!hcd->uses_new_polling)
839 			timer_delete(&hcd->rh_timer);
840 		if (urb == hcd->status_urb) {
841 			hcd->status_urb = NULL;
842 			usb_hcd_unlink_urb_from_ep(hcd, urb);
843 			usb_hcd_giveback_urb(hcd, urb, status);
844 		}
845 	}
846  done:
847 	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
848 	return rc;
849 }
850 
851 
852 /*-------------------------------------------------------------------------*/
853 
854 /**
855  * usb_bus_init - shared initialization code
856  * @bus: the bus structure being initialized
857  *
858  * This code is used to initialize a usb_bus structure, memory for which is
859  * separately managed.
860  */
861 static void usb_bus_init (struct usb_bus *bus)
862 {
863 	memset(&bus->devmap, 0, sizeof(bus->devmap));
864 
865 	bus->devnum_next = 1;
866 
867 	bus->root_hub = NULL;
868 	bus->busnum = -1;
869 	bus->bandwidth_allocated = 0;
870 	bus->bandwidth_int_reqs  = 0;
871 	bus->bandwidth_isoc_reqs = 0;
872 	mutex_init(&bus->devnum_next_mutex);
873 }
874 
875 /*-------------------------------------------------------------------------*/
876 
877 /**
878  * usb_register_bus - registers the USB host controller with the usb core
879  * @bus: pointer to the bus to register
880  *
881  * Context: task context, might sleep.
882  *
883  * Assigns a bus number, and links the controller into usbcore data
884  * structures so that it can be seen by scanning the bus list.
885  *
886  * Return: 0 if successful. A negative error code otherwise.
887  */
888 static int usb_register_bus(struct usb_bus *bus)
889 {
890 	int result = -E2BIG;
891 	int busnum;
892 
893 	mutex_lock(&usb_bus_idr_lock);
894 	busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL);
895 	if (busnum < 0) {
896 		pr_err("%s: failed to get bus number\n", usbcore_name);
897 		goto error_find_busnum;
898 	}
899 	bus->busnum = busnum;
900 	mutex_unlock(&usb_bus_idr_lock);
901 
902 	usb_notify_add_bus(bus);
903 
904 	dev_info (bus->controller, "new USB bus registered, assigned bus "
905 		  "number %d\n", bus->busnum);
906 	return 0;
907 
908 error_find_busnum:
909 	mutex_unlock(&usb_bus_idr_lock);
910 	return result;
911 }
912 
913 /**
914  * usb_deregister_bus - deregisters the USB host controller
915  * @bus: pointer to the bus to deregister
916  *
917  * Context: task context, might sleep.
918  *
919  * Recycles the bus number, and unlinks the controller from usbcore data
920  * structures so that it won't be seen by scanning the bus list.
921  */
922 static void usb_deregister_bus (struct usb_bus *bus)
923 {
924 	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
925 
926 	/*
927 	 * NOTE: make sure that all the devices are removed by the
928 	 * controller code, as well as having it call this when cleaning
929 	 * itself up
930 	 */
931 	mutex_lock(&usb_bus_idr_lock);
932 	idr_remove(&usb_bus_idr, bus->busnum);
933 	mutex_unlock(&usb_bus_idr_lock);
934 
935 	usb_notify_remove_bus(bus);
936 }
937 
938 /**
939  * register_root_hub - called by usb_add_hcd() to register a root hub
940  * @hcd: host controller for this root hub
941  *
942  * This function registers the root hub with the USB subsystem.  It sets up
943  * the device properly in the device tree and then calls usb_new_device()
944  * to register the usb device.  It also assigns the root hub's USB address
945  * (always 1).
946  *
947  * Return: 0 if successful. A negative error code otherwise.
948  */
949 static int register_root_hub(struct usb_hcd *hcd)
950 {
951 	struct device *parent_dev = hcd->self.controller;
952 	struct usb_device *usb_dev = hcd->self.root_hub;
953 	struct usb_device_descriptor *descr;
954 	const int devnum = 1;
955 	int retval;
956 
957 	usb_dev->devnum = devnum;
958 	usb_dev->bus->devnum_next = devnum + 1;
959 	set_bit(devnum, usb_dev->bus->devmap);
960 	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
961 
962 	mutex_lock(&usb_bus_idr_lock);
963 
964 	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
965 	descr = usb_get_device_descriptor(usb_dev);
966 	if (IS_ERR(descr)) {
967 		retval = PTR_ERR(descr);
968 		mutex_unlock(&usb_bus_idr_lock);
969 		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
970 				dev_name(&usb_dev->dev), retval);
971 		return retval;
972 	}
973 	usb_dev->descriptor = *descr;
974 	kfree(descr);
975 
976 	if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
977 		retval = usb_get_bos_descriptor(usb_dev);
978 		if (!retval) {
979 			usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
980 		} else if (usb_dev->speed >= USB_SPEED_SUPER) {
981 			mutex_unlock(&usb_bus_idr_lock);
982 			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
983 					dev_name(&usb_dev->dev), retval);
984 			return retval;
985 		}
986 	}
987 
988 	retval = usb_new_device (usb_dev);
989 	if (retval) {
990 		dev_err (parent_dev, "can't register root hub for %s, %d\n",
991 				dev_name(&usb_dev->dev), retval);
992 	} else {
993 		spin_lock_irq (&hcd_root_hub_lock);
994 		hcd->rh_registered = 1;
995 		spin_unlock_irq (&hcd_root_hub_lock);
996 
997 		/* Did the HC die before the root hub was registered? */
998 		if (HCD_DEAD(hcd))
999 			usb_hc_died (hcd);	/* This time clean up */
1000 	}
1001 	mutex_unlock(&usb_bus_idr_lock);
1002 
1003 	return retval;
1004 }
1005 
1006 /*
1007  * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1008  * @bus: the bus which the root hub belongs to
1009  * @portnum: the port which is being resumed
1010  *
1011  * HCDs should call this function when they know that a resume signal is
1012  * being sent to a root-hub port.  The root hub will be prevented from
1013  * going into autosuspend until usb_hcd_end_port_resume() is called.
1014  *
1015  * The bus's private lock must be held by the caller.
1016  */
1017 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1018 {
1019 	unsigned bit = 1 << portnum;
1020 
1021 	if (!(bus->resuming_ports & bit)) {
1022 		bus->resuming_ports |= bit;
1023 		pm_runtime_get_noresume(&bus->root_hub->dev);
1024 	}
1025 }
1026 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1027 
1028 /*
1029  * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1030  * @bus: the bus which the root hub belongs to
1031  * @portnum: the port which is being resumed
1032  *
1033  * HCDs should call this function when they know that a resume signal has
1034  * stopped being sent to a root-hub port.  The root hub will be allowed to
1035  * autosuspend again.
1036  *
1037  * The bus's private lock must be held by the caller.
1038  */
1039 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1040 {
1041 	unsigned bit = 1 << portnum;
1042 
1043 	if (bus->resuming_ports & bit) {
1044 		bus->resuming_ports &= ~bit;
1045 		pm_runtime_put_noidle(&bus->root_hub->dev);
1046 	}
1047 }
1048 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1049 
1050 /*-------------------------------------------------------------------------*/
1051 
1052 /**
1053  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1054  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1055  * @is_input: true iff the transaction sends data to the host
1056  * @isoc: true for isochronous transactions, false for interrupt ones
1057  * @bytecount: how many bytes in the transaction.
1058  *
1059  * Return: Approximate bus time in nanoseconds for a periodic transaction.
1060  *
1061  * Note:
1062  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1063  * scheduled in software, this function is only used for such scheduling.
1064  */
1065 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1066 {
1067 	unsigned long	tmp;
1068 
1069 	switch (speed) {
1070 	case USB_SPEED_LOW: 	/* INTR only */
1071 		if (is_input) {
1072 			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1073 			return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1074 		} else {
1075 			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1076 			return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1077 		}
1078 	case USB_SPEED_FULL:	/* ISOC or INTR */
1079 		if (isoc) {
1080 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1081 			return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1082 		} else {
1083 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1084 			return 9107L + BW_HOST_DELAY + tmp;
1085 		}
1086 	case USB_SPEED_HIGH:	/* ISOC or INTR */
1087 		/* FIXME adjust for input vs output */
1088 		if (isoc)
1089 			tmp = HS_NSECS_ISO (bytecount);
1090 		else
1091 			tmp = HS_NSECS (bytecount);
1092 		return tmp;
1093 	default:
1094 		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1095 		return -1;
1096 	}
1097 }
1098 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1099 
1100 
1101 /*-------------------------------------------------------------------------*/
1102 
1103 /*
1104  * Generic HC operations.
1105  */
1106 
1107 /*-------------------------------------------------------------------------*/
1108 
1109 /**
1110  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1111  * @hcd: host controller to which @urb was submitted
1112  * @urb: URB being submitted
1113  *
1114  * Host controller drivers should call this routine in their enqueue()
1115  * method.  The HCD's private spinlock must be held and interrupts must
1116  * be disabled.  The actions carried out here are required for URB
1117  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1118  *
1119  * Return: 0 for no error, otherwise a negative error code (in which case
1120  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1121  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1122  * the private spinlock and returning.
1123  */
1124 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1125 {
1126 	int		rc = 0;
1127 
1128 	spin_lock(&hcd_urb_list_lock);
1129 
1130 	/* Check that the URB isn't being killed */
1131 	if (unlikely(atomic_read(&urb->reject))) {
1132 		rc = -EPERM;
1133 		goto done;
1134 	}
1135 
1136 	if (unlikely(!urb->ep->enabled)) {
1137 		rc = -ENOENT;
1138 		goto done;
1139 	}
1140 
1141 	if (unlikely(!urb->dev->can_submit)) {
1142 		rc = -EHOSTUNREACH;
1143 		goto done;
1144 	}
1145 
1146 	/*
1147 	 * Check the host controller's state and add the URB to the
1148 	 * endpoint's queue.
1149 	 */
1150 	if (HCD_RH_RUNNING(hcd)) {
1151 		urb->unlinked = 0;
1152 		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1153 	} else {
1154 		rc = -ESHUTDOWN;
1155 		goto done;
1156 	}
1157  done:
1158 	spin_unlock(&hcd_urb_list_lock);
1159 	return rc;
1160 }
1161 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1162 
1163 /**
1164  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1165  * @hcd: host controller to which @urb was submitted
1166  * @urb: URB being checked for unlinkability
1167  * @status: error code to store in @urb if the unlink succeeds
1168  *
1169  * Host controller drivers should call this routine in their dequeue()
1170  * method.  The HCD's private spinlock must be held and interrupts must
1171  * be disabled.  The actions carried out here are required for making
1172  * sure than an unlink is valid.
1173  *
1174  * Return: 0 for no error, otherwise a negative error code (in which case
1175  * the dequeue() method must fail).  The possible error codes are:
1176  *
1177  *	-EIDRM: @urb was not submitted or has already completed.
1178  *		The completion function may not have been called yet.
1179  *
1180  *	-EBUSY: @urb has already been unlinked.
1181  */
1182 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1183 		int status)
1184 {
1185 	struct list_head	*tmp;
1186 
1187 	/* insist the urb is still queued */
1188 	list_for_each(tmp, &urb->ep->urb_list) {
1189 		if (tmp == &urb->urb_list)
1190 			break;
1191 	}
1192 	if (tmp != &urb->urb_list)
1193 		return -EIDRM;
1194 
1195 	/* Any status except -EINPROGRESS means something already started to
1196 	 * unlink this URB from the hardware.  So there's no more work to do.
1197 	 */
1198 	if (urb->unlinked)
1199 		return -EBUSY;
1200 	urb->unlinked = status;
1201 	return 0;
1202 }
1203 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1204 
1205 /**
1206  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1207  * @hcd: host controller to which @urb was submitted
1208  * @urb: URB being unlinked
1209  *
1210  * Host controller drivers should call this routine before calling
1211  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1212  * interrupts must be disabled.  The actions carried out here are required
1213  * for URB completion.
1214  */
1215 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1216 {
1217 	/* clear all state linking urb to this dev (and hcd) */
1218 	spin_lock(&hcd_urb_list_lock);
1219 	list_del_init(&urb->urb_list);
1220 	spin_unlock(&hcd_urb_list_lock);
1221 }
1222 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1223 
1224 /*
1225  * Some usb host controllers can only perform dma using a small SRAM area,
1226  * or have restrictions on addressable DRAM.
1227  * The usb core itself is however optimized for host controllers that can dma
1228  * using regular system memory - like pci devices doing bus mastering.
1229  *
1230  * To support host controllers with limited dma capabilities we provide dma
1231  * bounce buffers. This feature can be enabled by initializing
1232  * hcd->localmem_pool using usb_hcd_setup_local_mem().
1233  *
1234  * The initialized hcd->localmem_pool then tells the usb code to allocate all
1235  * data for dma using the genalloc API.
1236  *
1237  * So, to summarize...
1238  *
1239  * - We need "local" memory, canonical example being
1240  *   a small SRAM on a discrete controller being the
1241  *   only memory that the controller can read ...
1242  *   (a) "normal" kernel memory is no good, and
1243  *   (b) there's not enough to share
1244  *
1245  * - So we use that, even though the primary requirement
1246  *   is that the memory be "local" (hence addressable
1247  *   by that device), not "coherent".
1248  *
1249  */
1250 
1251 static int hcd_alloc_coherent(struct usb_bus *bus,
1252 			      gfp_t mem_flags, dma_addr_t *dma_handle,
1253 			      void **vaddr_handle, size_t size,
1254 			      enum dma_data_direction dir)
1255 {
1256 	unsigned char *vaddr;
1257 
1258 	if (*vaddr_handle == NULL) {
1259 		WARN_ON_ONCE(1);
1260 		return -EFAULT;
1261 	}
1262 
1263 	vaddr = hcd_buffer_alloc(bus, size + sizeof(unsigned long),
1264 				 mem_flags, dma_handle);
1265 	if (!vaddr)
1266 		return -ENOMEM;
1267 
1268 	/*
1269 	 * Store the virtual address of the buffer at the end
1270 	 * of the allocated dma buffer. The size of the buffer
1271 	 * may be uneven so use unaligned functions instead
1272 	 * of just rounding up. It makes sense to optimize for
1273 	 * memory footprint over access speed since the amount
1274 	 * of memory available for dma may be limited.
1275 	 */
1276 	put_unaligned((unsigned long)*vaddr_handle,
1277 		      (unsigned long *)(vaddr + size));
1278 
1279 	if (dir == DMA_TO_DEVICE)
1280 		memcpy(vaddr, *vaddr_handle, size);
1281 
1282 	*vaddr_handle = vaddr;
1283 	return 0;
1284 }
1285 
1286 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1287 			      void **vaddr_handle, size_t size,
1288 			      enum dma_data_direction dir)
1289 {
1290 	unsigned char *vaddr = *vaddr_handle;
1291 
1292 	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1293 
1294 	if (dir == DMA_FROM_DEVICE)
1295 		memcpy(vaddr, *vaddr_handle, size);
1296 
1297 	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1298 
1299 	*vaddr_handle = vaddr;
1300 	*dma_handle = 0;
1301 }
1302 
1303 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1304 {
1305 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1306 	    (urb->transfer_flags & URB_SETUP_MAP_SINGLE))
1307 		dma_unmap_single(hcd->self.sysdev,
1308 				urb->setup_dma,
1309 				sizeof(struct usb_ctrlrequest),
1310 				DMA_TO_DEVICE);
1311 	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1312 		hcd_free_coherent(urb->dev->bus,
1313 				&urb->setup_dma,
1314 				(void **) &urb->setup_packet,
1315 				sizeof(struct usb_ctrlrequest),
1316 				DMA_TO_DEVICE);
1317 
1318 	/* Make it safe to call this routine more than once */
1319 	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1320 }
1321 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1322 
1323 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1324 {
1325 	if (hcd->driver->unmap_urb_for_dma)
1326 		hcd->driver->unmap_urb_for_dma(hcd, urb);
1327 	else
1328 		usb_hcd_unmap_urb_for_dma(hcd, urb);
1329 }
1330 
1331 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1332 {
1333 	enum dma_data_direction dir;
1334 
1335 	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1336 
1337 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1338 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1339 	    (urb->transfer_flags & URB_DMA_MAP_SG)) {
1340 		dma_unmap_sg(hcd->self.sysdev,
1341 				urb->sg,
1342 				urb->num_sgs,
1343 				dir);
1344 	} else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1345 		 (urb->transfer_flags & URB_DMA_MAP_PAGE)) {
1346 		dma_unmap_page(hcd->self.sysdev,
1347 				urb->transfer_dma,
1348 				urb->transfer_buffer_length,
1349 				dir);
1350 	} else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1351 		 (urb->transfer_flags & URB_DMA_MAP_SINGLE)) {
1352 		dma_unmap_single(hcd->self.sysdev,
1353 				urb->transfer_dma,
1354 				urb->transfer_buffer_length,
1355 				dir);
1356 	} else if (urb->transfer_flags & URB_MAP_LOCAL) {
1357 		hcd_free_coherent(urb->dev->bus,
1358 				&urb->transfer_dma,
1359 				&urb->transfer_buffer,
1360 				urb->transfer_buffer_length,
1361 				dir);
1362 	} else if ((urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP) && urb->sgt) {
1363 		dma_sync_sgtable_for_cpu(hcd->self.sysdev, urb->sgt, dir);
1364 		if (dir == DMA_FROM_DEVICE)
1365 			invalidate_kernel_vmap_range(urb->transfer_buffer,
1366 						     urb->transfer_buffer_length);
1367 	}
1368 
1369 	/* Make it safe to call this routine more than once */
1370 	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1371 			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1372 }
1373 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1374 
1375 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1376 			   gfp_t mem_flags)
1377 {
1378 	if (hcd->driver->map_urb_for_dma)
1379 		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1380 	else
1381 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1382 }
1383 
1384 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1385 			    gfp_t mem_flags)
1386 {
1387 	enum dma_data_direction dir;
1388 	int ret = 0;
1389 
1390 	/* Map the URB's buffers for DMA access.
1391 	 * Lower level HCD code should use *_dma exclusively,
1392 	 * unless it uses pio or talks to another transport,
1393 	 * or uses the provided scatter gather list for bulk.
1394 	 */
1395 
1396 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1397 		if (hcd->self.uses_pio_for_control)
1398 			return ret;
1399 		if (hcd->localmem_pool) {
1400 			ret = hcd_alloc_coherent(
1401 					urb->dev->bus, mem_flags,
1402 					&urb->setup_dma,
1403 					(void **)&urb->setup_packet,
1404 					sizeof(struct usb_ctrlrequest),
1405 					DMA_TO_DEVICE);
1406 			if (ret)
1407 				return ret;
1408 			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1409 		} else if (hcd_uses_dma(hcd)) {
1410 			if (object_is_on_stack(urb->setup_packet)) {
1411 				WARN_ONCE(1, "setup packet is on stack\n");
1412 				return -EAGAIN;
1413 			}
1414 
1415 			urb->setup_dma = dma_map_single(
1416 					hcd->self.sysdev,
1417 					urb->setup_packet,
1418 					sizeof(struct usb_ctrlrequest),
1419 					DMA_TO_DEVICE);
1420 			if (dma_mapping_error(hcd->self.sysdev,
1421 						urb->setup_dma))
1422 				return -EAGAIN;
1423 			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1424 		}
1425 	}
1426 
1427 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1428 	if (urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP) {
1429 		if (!urb->sgt)
1430 			return 0;
1431 
1432 		if (dir == DMA_TO_DEVICE)
1433 			flush_kernel_vmap_range(urb->transfer_buffer,
1434 						urb->transfer_buffer_length);
1435 		dma_sync_sgtable_for_device(hcd->self.sysdev, urb->sgt, dir);
1436 	} else if (urb->transfer_buffer_length != 0) {
1437 		if (hcd->localmem_pool) {
1438 			ret = hcd_alloc_coherent(
1439 					urb->dev->bus, mem_flags,
1440 					&urb->transfer_dma,
1441 					&urb->transfer_buffer,
1442 					urb->transfer_buffer_length,
1443 					dir);
1444 			if (ret == 0)
1445 				urb->transfer_flags |= URB_MAP_LOCAL;
1446 		} else if (hcd_uses_dma(hcd)) {
1447 			if (urb->num_sgs) {
1448 				int n;
1449 
1450 				/* We don't support sg for isoc transfers ! */
1451 				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1452 					WARN_ON(1);
1453 					return -EINVAL;
1454 				}
1455 
1456 				n = dma_map_sg(
1457 						hcd->self.sysdev,
1458 						urb->sg,
1459 						urb->num_sgs,
1460 						dir);
1461 				if (!n)
1462 					ret = -EAGAIN;
1463 				else
1464 					urb->transfer_flags |= URB_DMA_MAP_SG;
1465 				urb->num_mapped_sgs = n;
1466 				if (n != urb->num_sgs)
1467 					urb->transfer_flags |=
1468 							URB_DMA_SG_COMBINED;
1469 			} else if (urb->sg) {
1470 				struct scatterlist *sg = urb->sg;
1471 				urb->transfer_dma = dma_map_page(
1472 						hcd->self.sysdev,
1473 						sg_page(sg),
1474 						sg->offset,
1475 						urb->transfer_buffer_length,
1476 						dir);
1477 				if (dma_mapping_error(hcd->self.sysdev,
1478 						urb->transfer_dma))
1479 					ret = -EAGAIN;
1480 				else
1481 					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1482 			} else if (object_is_on_stack(urb->transfer_buffer)) {
1483 				WARN_ONCE(1, "transfer buffer is on stack\n");
1484 				ret = -EAGAIN;
1485 			} else {
1486 				urb->transfer_dma = dma_map_single(
1487 						hcd->self.sysdev,
1488 						urb->transfer_buffer,
1489 						urb->transfer_buffer_length,
1490 						dir);
1491 				if (dma_mapping_error(hcd->self.sysdev,
1492 						urb->transfer_dma))
1493 					ret = -EAGAIN;
1494 				else
1495 					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1496 			}
1497 		}
1498 		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1499 				URB_SETUP_MAP_LOCAL)))
1500 			usb_hcd_unmap_urb_for_dma(hcd, urb);
1501 	}
1502 	return ret;
1503 }
1504 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1505 
1506 /*-------------------------------------------------------------------------*/
1507 
1508 /* may be called in any context with a valid urb->dev usecount
1509  * caller surrenders "ownership" of urb
1510  * expects usb_submit_urb() to have sanity checked and conditioned all
1511  * inputs in the urb
1512  */
1513 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1514 {
1515 	int			status;
1516 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1517 
1518 	/* increment urb's reference count as part of giving it to the HCD
1519 	 * (which will control it).  HCD guarantees that it either returns
1520 	 * an error or calls giveback(), but not both.
1521 	 */
1522 	usb_get_urb(urb);
1523 	atomic_inc(&urb->use_count);
1524 	atomic_inc(&urb->dev->urbnum);
1525 	usbmon_urb_submit(&hcd->self, urb);
1526 
1527 	/* NOTE requirements on root-hub callers (usbfs and the hub
1528 	 * driver, for now):  URBs' urb->transfer_buffer must be
1529 	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1530 	 * they could clobber root hub response data.  Also, control
1531 	 * URBs must be submitted in process context with interrupts
1532 	 * enabled.
1533 	 */
1534 
1535 	if (is_root_hub(urb->dev)) {
1536 		status = rh_urb_enqueue(hcd, urb);
1537 	} else {
1538 		status = map_urb_for_dma(hcd, urb, mem_flags);
1539 		if (likely(status == 0)) {
1540 			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1541 			if (unlikely(status))
1542 				unmap_urb_for_dma(hcd, urb);
1543 		}
1544 	}
1545 
1546 	if (unlikely(status)) {
1547 		usbmon_urb_submit_error(&hcd->self, urb, status);
1548 		urb->hcpriv = NULL;
1549 		INIT_LIST_HEAD(&urb->urb_list);
1550 		atomic_dec(&urb->use_count);
1551 		/*
1552 		 * Order the write of urb->use_count above before the read
1553 		 * of urb->reject below.  Pairs with the memory barriers in
1554 		 * usb_kill_urb() and usb_poison_urb().
1555 		 */
1556 		smp_mb__after_atomic();
1557 
1558 		atomic_dec(&urb->dev->urbnum);
1559 		if (atomic_read(&urb->reject))
1560 			wake_up(&usb_kill_urb_queue);
1561 		usb_put_urb(urb);
1562 	}
1563 	return status;
1564 }
1565 
1566 /*-------------------------------------------------------------------------*/
1567 
1568 /* this makes the hcd giveback() the urb more quickly, by kicking it
1569  * off hardware queues (which may take a while) and returning it as
1570  * soon as practical.  we've already set up the urb's return status,
1571  * but we can't know if the callback completed already.
1572  */
1573 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1574 {
1575 	int		value;
1576 
1577 	if (is_root_hub(urb->dev))
1578 		value = usb_rh_urb_dequeue(hcd, urb, status);
1579 	else {
1580 
1581 		/* The only reason an HCD might fail this call is if
1582 		 * it has not yet fully queued the urb to begin with.
1583 		 * Such failures should be harmless. */
1584 		value = hcd->driver->urb_dequeue(hcd, urb, status);
1585 	}
1586 	return value;
1587 }
1588 
1589 /*
1590  * called in any context
1591  *
1592  * caller guarantees urb won't be recycled till both unlink()
1593  * and the urb's completion function return
1594  */
1595 int usb_hcd_unlink_urb (struct urb *urb, int status)
1596 {
1597 	struct usb_hcd		*hcd;
1598 	struct usb_device	*udev = urb->dev;
1599 	int			retval = -EIDRM;
1600 	unsigned long		flags;
1601 
1602 	/* Prevent the device and bus from going away while
1603 	 * the unlink is carried out.  If they are already gone
1604 	 * then urb->use_count must be 0, since disconnected
1605 	 * devices can't have any active URBs.
1606 	 */
1607 	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1608 	if (atomic_read(&urb->use_count) > 0) {
1609 		retval = 0;
1610 		usb_get_dev(udev);
1611 	}
1612 	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1613 	if (retval == 0) {
1614 		hcd = bus_to_hcd(urb->dev->bus);
1615 		retval = unlink1(hcd, urb, status);
1616 		if (retval == 0)
1617 			retval = -EINPROGRESS;
1618 		else if (retval != -EIDRM && retval != -EBUSY)
1619 			dev_dbg(&udev->dev, "hcd_unlink_urb %p fail %d\n",
1620 					urb, retval);
1621 		usb_put_dev(udev);
1622 	}
1623 	return retval;
1624 }
1625 
1626 /*-------------------------------------------------------------------------*/
1627 
1628 static void __usb_hcd_giveback_urb(struct urb *urb)
1629 {
1630 	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1631 	struct usb_anchor *anchor = urb->anchor;
1632 	int status = urb->unlinked;
1633 
1634 	urb->hcpriv = NULL;
1635 	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1636 	    urb->actual_length < urb->transfer_buffer_length &&
1637 	    !status))
1638 		status = -EREMOTEIO;
1639 
1640 	unmap_urb_for_dma(hcd, urb);
1641 	usbmon_urb_complete(&hcd->self, urb, status);
1642 	usb_anchor_suspend_wakeups(anchor);
1643 	usb_unanchor_urb(urb);
1644 	if (likely(status == 0))
1645 		usb_led_activity(USB_LED_EVENT_HOST);
1646 
1647 	/* pass ownership to the completion handler */
1648 	urb->status = status;
1649 	/*
1650 	 * This function can be called in task context inside another remote
1651 	 * coverage collection section, but kcov doesn't support that kind of
1652 	 * recursion yet. Only collect coverage in softirq context for now.
1653 	 */
1654 	kcov_remote_start_usb_softirq((u64)urb->dev->bus->busnum);
1655 	urb->complete(urb);
1656 	kcov_remote_stop_softirq();
1657 
1658 	usb_anchor_resume_wakeups(anchor);
1659 	atomic_dec(&urb->use_count);
1660 	/*
1661 	 * Order the write of urb->use_count above before the read
1662 	 * of urb->reject below.  Pairs with the memory barriers in
1663 	 * usb_kill_urb() and usb_poison_urb().
1664 	 */
1665 	smp_mb__after_atomic();
1666 
1667 	if (unlikely(atomic_read(&urb->reject)))
1668 		wake_up(&usb_kill_urb_queue);
1669 	usb_put_urb(urb);
1670 }
1671 
1672 static void usb_giveback_urb_bh(struct work_struct *work)
1673 {
1674 	struct giveback_urb_bh *bh =
1675 		container_of(work, struct giveback_urb_bh, bh);
1676 	struct list_head local_list;
1677 
1678 	spin_lock_irq(&bh->lock);
1679 	bh->running = true;
1680 	list_replace_init(&bh->head, &local_list);
1681 	spin_unlock_irq(&bh->lock);
1682 
1683 	while (!list_empty(&local_list)) {
1684 		struct urb *urb;
1685 
1686 		urb = list_entry(local_list.next, struct urb, urb_list);
1687 		list_del_init(&urb->urb_list);
1688 		bh->completing_ep = urb->ep;
1689 		__usb_hcd_giveback_urb(urb);
1690 		bh->completing_ep = NULL;
1691 	}
1692 
1693 	/*
1694 	 * giveback new URBs next time to prevent this function
1695 	 * from not exiting for a long time.
1696 	 */
1697 	spin_lock_irq(&bh->lock);
1698 	if (!list_empty(&bh->head)) {
1699 		if (bh->high_prio)
1700 			queue_work(system_bh_highpri_wq, &bh->bh);
1701 		else
1702 			queue_work(system_bh_wq, &bh->bh);
1703 	}
1704 	bh->running = false;
1705 	spin_unlock_irq(&bh->lock);
1706 }
1707 
1708 /**
1709  * usb_hcd_giveback_urb - return URB from HCD to device driver
1710  * @hcd: host controller returning the URB
1711  * @urb: urb being returned to the USB device driver.
1712  * @status: completion status code for the URB.
1713  *
1714  * Context: atomic. The completion callback is invoked either in a work queue
1715  * (BH) context or in the caller's context, depending on whether the HCD_BH
1716  * flag is set in the @hcd structure, except that URBs submitted to the
1717  * root hub always complete in BH context.
1718  *
1719  * This hands the URB from HCD to its USB device driver, using its
1720  * completion function.  The HCD has freed all per-urb resources
1721  * (and is done using urb->hcpriv).  It also released all HCD locks;
1722  * the device driver won't cause problems if it frees, modifies,
1723  * or resubmits this URB.
1724  *
1725  * If @urb was unlinked, the value of @status will be overridden by
1726  * @urb->unlinked.  Erroneous short transfers are detected in case
1727  * the HCD hasn't checked for them.
1728  */
1729 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1730 {
1731 	struct giveback_urb_bh *bh;
1732 	bool running;
1733 
1734 	/* pass status to BH via unlinked */
1735 	if (likely(!urb->unlinked))
1736 		urb->unlinked = status;
1737 
1738 	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1739 		__usb_hcd_giveback_urb(urb);
1740 		return;
1741 	}
1742 
1743 	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe))
1744 		bh = &hcd->high_prio_bh;
1745 	else
1746 		bh = &hcd->low_prio_bh;
1747 
1748 	spin_lock(&bh->lock);
1749 	list_add_tail(&urb->urb_list, &bh->head);
1750 	running = bh->running;
1751 	spin_unlock(&bh->lock);
1752 
1753 	if (running)
1754 		;
1755 	else if (bh->high_prio)
1756 		queue_work(system_bh_highpri_wq, &bh->bh);
1757 	else
1758 		queue_work(system_bh_wq, &bh->bh);
1759 }
1760 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1761 
1762 /*-------------------------------------------------------------------------*/
1763 
1764 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1765  * queue to drain completely.  The caller must first insure that no more
1766  * URBs can be submitted for this endpoint.
1767  */
1768 void usb_hcd_flush_endpoint(struct usb_device *udev,
1769 		struct usb_host_endpoint *ep)
1770 {
1771 	struct usb_hcd		*hcd;
1772 	struct urb		*urb;
1773 
1774 	if (!ep)
1775 		return;
1776 	might_sleep();
1777 	hcd = bus_to_hcd(udev->bus);
1778 
1779 	/* No more submits can occur */
1780 	spin_lock_irq(&hcd_urb_list_lock);
1781 rescan:
1782 	list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) {
1783 		int	is_in;
1784 
1785 		if (urb->unlinked)
1786 			continue;
1787 		usb_get_urb (urb);
1788 		is_in = usb_urb_dir_in(urb);
1789 		spin_unlock(&hcd_urb_list_lock);
1790 
1791 		/* kick hcd */
1792 		unlink1(hcd, urb, -ESHUTDOWN);
1793 		dev_dbg (hcd->self.controller,
1794 			"shutdown urb %p ep%d%s-%s\n",
1795 			urb, usb_endpoint_num(&ep->desc),
1796 			is_in ? "in" : "out",
1797 			usb_ep_type_string(usb_endpoint_type(&ep->desc)));
1798 		usb_put_urb (urb);
1799 
1800 		/* list contents may have changed */
1801 		spin_lock(&hcd_urb_list_lock);
1802 		goto rescan;
1803 	}
1804 	spin_unlock_irq(&hcd_urb_list_lock);
1805 
1806 	/* Wait until the endpoint queue is completely empty */
1807 	while (!list_empty (&ep->urb_list)) {
1808 		spin_lock_irq(&hcd_urb_list_lock);
1809 
1810 		/* The list may have changed while we acquired the spinlock */
1811 		urb = NULL;
1812 		if (!list_empty (&ep->urb_list)) {
1813 			urb = list_entry (ep->urb_list.prev, struct urb,
1814 					urb_list);
1815 			usb_get_urb (urb);
1816 		}
1817 		spin_unlock_irq(&hcd_urb_list_lock);
1818 
1819 		if (urb) {
1820 			usb_kill_urb (urb);
1821 			usb_put_urb (urb);
1822 		}
1823 	}
1824 }
1825 
1826 /**
1827  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1828  *				the bus bandwidth
1829  * @udev: target &usb_device
1830  * @new_config: new configuration to install
1831  * @cur_alt: the current alternate interface setting
1832  * @new_alt: alternate interface setting that is being installed
1833  *
1834  * To change configurations, pass in the new configuration in new_config,
1835  * and pass NULL for cur_alt and new_alt.
1836  *
1837  * To reset a device's configuration (put the device in the ADDRESSED state),
1838  * pass in NULL for new_config, cur_alt, and new_alt.
1839  *
1840  * To change alternate interface settings, pass in NULL for new_config,
1841  * pass in the current alternate interface setting in cur_alt,
1842  * and pass in the new alternate interface setting in new_alt.
1843  *
1844  * Return: An error if the requested bandwidth change exceeds the
1845  * bus bandwidth or host controller internal resources.
1846  */
1847 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1848 		struct usb_host_config *new_config,
1849 		struct usb_host_interface *cur_alt,
1850 		struct usb_host_interface *new_alt)
1851 {
1852 	int num_intfs, i, j;
1853 	struct usb_host_interface *alt = NULL;
1854 	int ret = 0;
1855 	struct usb_hcd *hcd;
1856 	struct usb_host_endpoint *ep;
1857 
1858 	hcd = bus_to_hcd(udev->bus);
1859 	if (!hcd->driver->check_bandwidth)
1860 		return 0;
1861 
1862 	/* Configuration is being removed - set configuration 0 */
1863 	if (!new_config && !cur_alt) {
1864 		for (i = 1; i < 16; ++i) {
1865 			ep = udev->ep_out[i];
1866 			if (ep)
1867 				hcd->driver->drop_endpoint(hcd, udev, ep);
1868 			ep = udev->ep_in[i];
1869 			if (ep)
1870 				hcd->driver->drop_endpoint(hcd, udev, ep);
1871 		}
1872 		hcd->driver->check_bandwidth(hcd, udev);
1873 		return 0;
1874 	}
1875 	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1876 	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1877 	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1878 	 * ok to exclude it.
1879 	 */
1880 	if (new_config) {
1881 		num_intfs = new_config->desc.bNumInterfaces;
1882 		/* Remove endpoints (except endpoint 0, which is always on the
1883 		 * schedule) from the old config from the schedule
1884 		 */
1885 		for (i = 1; i < 16; ++i) {
1886 			ep = udev->ep_out[i];
1887 			if (ep) {
1888 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1889 				if (ret < 0)
1890 					goto reset;
1891 			}
1892 			ep = udev->ep_in[i];
1893 			if (ep) {
1894 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1895 				if (ret < 0)
1896 					goto reset;
1897 			}
1898 		}
1899 		for (i = 0; i < num_intfs; ++i) {
1900 			struct usb_host_interface *first_alt;
1901 			int iface_num;
1902 
1903 			first_alt = &new_config->intf_cache[i]->altsetting[0];
1904 			iface_num = first_alt->desc.bInterfaceNumber;
1905 			/* Set up endpoints for alternate interface setting 0 */
1906 			alt = usb_find_alt_setting(new_config, iface_num, 0);
1907 			if (!alt)
1908 				/* No alt setting 0? Pick the first setting. */
1909 				alt = first_alt;
1910 
1911 			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1912 				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1913 				if (ret < 0)
1914 					goto reset;
1915 			}
1916 		}
1917 	}
1918 	if (cur_alt && new_alt) {
1919 		struct usb_interface *iface = usb_ifnum_to_if(udev,
1920 				cur_alt->desc.bInterfaceNumber);
1921 
1922 		if (!iface)
1923 			return -EINVAL;
1924 		if (iface->resetting_device) {
1925 			/*
1926 			 * The USB core just reset the device, so the xHCI host
1927 			 * and the device will think alt setting 0 is installed.
1928 			 * However, the USB core will pass in the alternate
1929 			 * setting installed before the reset as cur_alt.  Dig
1930 			 * out the alternate setting 0 structure, or the first
1931 			 * alternate setting if a broken device doesn't have alt
1932 			 * setting 0.
1933 			 */
1934 			cur_alt = usb_altnum_to_altsetting(iface, 0);
1935 			if (!cur_alt)
1936 				cur_alt = &iface->altsetting[0];
1937 		}
1938 
1939 		/* Drop all the endpoints in the current alt setting */
1940 		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
1941 			ret = hcd->driver->drop_endpoint(hcd, udev,
1942 					&cur_alt->endpoint[i]);
1943 			if (ret < 0)
1944 				goto reset;
1945 		}
1946 		/* Add all the endpoints in the new alt setting */
1947 		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
1948 			ret = hcd->driver->add_endpoint(hcd, udev,
1949 					&new_alt->endpoint[i]);
1950 			if (ret < 0)
1951 				goto reset;
1952 		}
1953 	}
1954 	ret = hcd->driver->check_bandwidth(hcd, udev);
1955 reset:
1956 	if (ret < 0)
1957 		hcd->driver->reset_bandwidth(hcd, udev);
1958 	return ret;
1959 }
1960 
1961 /* Disables the endpoint: synchronizes with the hcd to make sure all
1962  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
1963  * have been called previously.  Use for set_configuration, set_interface,
1964  * driver removal, physical disconnect.
1965  *
1966  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
1967  * type, maxpacket size, toggle, halt status, and scheduling.
1968  */
1969 void usb_hcd_disable_endpoint(struct usb_device *udev,
1970 		struct usb_host_endpoint *ep)
1971 {
1972 	struct usb_hcd		*hcd;
1973 
1974 	might_sleep();
1975 	hcd = bus_to_hcd(udev->bus);
1976 	if (hcd->driver->endpoint_disable)
1977 		hcd->driver->endpoint_disable(hcd, ep);
1978 }
1979 
1980 /**
1981  * usb_hcd_reset_endpoint - reset host endpoint state
1982  * @udev: USB device.
1983  * @ep:   the endpoint to reset.
1984  *
1985  * Resets any host endpoint state such as the toggle bit, sequence
1986  * number and current window.
1987  */
1988 void usb_hcd_reset_endpoint(struct usb_device *udev,
1989 			    struct usb_host_endpoint *ep)
1990 {
1991 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1992 
1993 	if (hcd->driver->endpoint_reset)
1994 		hcd->driver->endpoint_reset(hcd, ep);
1995 	else {
1996 		int epnum = usb_endpoint_num(&ep->desc);
1997 		int is_out = usb_endpoint_dir_out(&ep->desc);
1998 		int is_control = usb_endpoint_xfer_control(&ep->desc);
1999 
2000 		usb_settoggle(udev, epnum, is_out, 0);
2001 		if (is_control)
2002 			usb_settoggle(udev, epnum, !is_out, 0);
2003 	}
2004 }
2005 
2006 /**
2007  * usb_alloc_streams - allocate bulk endpoint stream IDs.
2008  * @interface:		alternate setting that includes all endpoints.
2009  * @eps:		array of endpoints that need streams.
2010  * @num_eps:		number of endpoints in the array.
2011  * @num_streams:	number of streams to allocate.
2012  * @mem_flags:		flags hcd should use to allocate memory.
2013  *
2014  * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
2015  * Drivers may queue multiple transfers to different stream IDs, which may
2016  * complete in a different order than they were queued.
2017  *
2018  * Return: On success, the number of allocated streams. On failure, a negative
2019  * error code.
2020  */
2021 int usb_alloc_streams(struct usb_interface *interface,
2022 		struct usb_host_endpoint **eps, unsigned int num_eps,
2023 		unsigned int num_streams, gfp_t mem_flags)
2024 {
2025 	struct usb_hcd *hcd;
2026 	struct usb_device *dev;
2027 	int i, ret;
2028 
2029 	dev = interface_to_usbdev(interface);
2030 	hcd = bus_to_hcd(dev->bus);
2031 	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2032 		return -EINVAL;
2033 	if (dev->speed < USB_SPEED_SUPER)
2034 		return -EINVAL;
2035 	if (dev->state < USB_STATE_CONFIGURED)
2036 		return -ENODEV;
2037 
2038 	for (i = 0; i < num_eps; i++) {
2039 		/* Streams only apply to bulk endpoints. */
2040 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2041 			return -EINVAL;
2042 		/* Re-alloc is not allowed */
2043 		if (eps[i]->streams)
2044 			return -EINVAL;
2045 	}
2046 
2047 	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2048 			num_streams, mem_flags);
2049 	if (ret < 0)
2050 		return ret;
2051 
2052 	for (i = 0; i < num_eps; i++)
2053 		eps[i]->streams = ret;
2054 
2055 	return ret;
2056 }
2057 EXPORT_SYMBOL_GPL(usb_alloc_streams);
2058 
2059 /**
2060  * usb_free_streams - free bulk endpoint stream IDs.
2061  * @interface:	alternate setting that includes all endpoints.
2062  * @eps:	array of endpoints to remove streams from.
2063  * @num_eps:	number of endpoints in the array.
2064  * @mem_flags:	flags hcd should use to allocate memory.
2065  *
2066  * Reverts a group of bulk endpoints back to not using stream IDs.
2067  * Can fail if we are given bad arguments, or HCD is broken.
2068  *
2069  * Return: 0 on success. On failure, a negative error code.
2070  */
2071 int usb_free_streams(struct usb_interface *interface,
2072 		struct usb_host_endpoint **eps, unsigned int num_eps,
2073 		gfp_t mem_flags)
2074 {
2075 	struct usb_hcd *hcd;
2076 	struct usb_device *dev;
2077 	int i, ret;
2078 
2079 	dev = interface_to_usbdev(interface);
2080 	hcd = bus_to_hcd(dev->bus);
2081 	if (dev->speed < USB_SPEED_SUPER)
2082 		return -EINVAL;
2083 
2084 	/* Double-free is not allowed */
2085 	for (i = 0; i < num_eps; i++)
2086 		if (!eps[i] || !eps[i]->streams)
2087 			return -EINVAL;
2088 
2089 	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2090 	if (ret < 0)
2091 		return ret;
2092 
2093 	for (i = 0; i < num_eps; i++)
2094 		eps[i]->streams = 0;
2095 
2096 	return ret;
2097 }
2098 EXPORT_SYMBOL_GPL(usb_free_streams);
2099 
2100 /* Protect against drivers that try to unlink URBs after the device
2101  * is gone, by waiting until all unlinks for @udev are finished.
2102  * Since we don't currently track URBs by device, simply wait until
2103  * nothing is running in the locked region of usb_hcd_unlink_urb().
2104  */
2105 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2106 {
2107 	spin_lock_irq(&hcd_urb_unlink_lock);
2108 	spin_unlock_irq(&hcd_urb_unlink_lock);
2109 }
2110 
2111 /*-------------------------------------------------------------------------*/
2112 
2113 /* called in any context */
2114 int usb_hcd_get_frame_number (struct usb_device *udev)
2115 {
2116 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
2117 
2118 	if (!HCD_RH_RUNNING(hcd))
2119 		return -ESHUTDOWN;
2120 	return hcd->driver->get_frame_number (hcd);
2121 }
2122 
2123 /*-------------------------------------------------------------------------*/
2124 #ifdef CONFIG_USB_HCD_TEST_MODE
2125 
2126 static void usb_ehset_completion(struct urb *urb)
2127 {
2128 	struct completion  *done = urb->context;
2129 
2130 	complete(done);
2131 }
2132 /*
2133  * Allocate and initialize a control URB. This request will be used by the
2134  * EHSET SINGLE_STEP_SET_FEATURE test in which the DATA and STATUS stages
2135  * of the GetDescriptor request are sent 15 seconds after the SETUP stage.
2136  * Return NULL if failed.
2137  */
2138 static struct urb *request_single_step_set_feature_urb(
2139 	struct usb_device	*udev,
2140 	void			*dr,
2141 	void			*buf,
2142 	struct completion	*done)
2143 {
2144 	struct urb *urb;
2145 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2146 
2147 	urb = usb_alloc_urb(0, GFP_KERNEL);
2148 	if (!urb)
2149 		return NULL;
2150 
2151 	urb->pipe = usb_rcvctrlpipe(udev, 0);
2152 
2153 	urb->ep = &udev->ep0;
2154 	urb->dev = udev;
2155 	urb->setup_packet = (void *)dr;
2156 	urb->transfer_buffer = buf;
2157 	urb->transfer_buffer_length = USB_DT_DEVICE_SIZE;
2158 	urb->complete = usb_ehset_completion;
2159 	urb->status = -EINPROGRESS;
2160 	urb->actual_length = 0;
2161 	urb->transfer_flags = URB_DIR_IN | URB_NO_TRANSFER_DMA_MAP;
2162 	usb_get_urb(urb);
2163 	atomic_inc(&urb->use_count);
2164 	atomic_inc(&urb->dev->urbnum);
2165 	if (map_urb_for_dma(hcd, urb, GFP_KERNEL)) {
2166 		usb_put_urb(urb);
2167 		usb_free_urb(urb);
2168 		return NULL;
2169 	}
2170 
2171 	urb->context = done;
2172 	return urb;
2173 }
2174 
2175 int ehset_single_step_set_feature(struct usb_hcd *hcd, int port)
2176 {
2177 	int retval = -ENOMEM;
2178 	struct usb_ctrlrequest *dr;
2179 	struct urb *urb;
2180 	struct usb_device *udev;
2181 	struct usb_device_descriptor *buf;
2182 	DECLARE_COMPLETION_ONSTACK(done);
2183 
2184 	/* Obtain udev of the rhub's child port */
2185 	udev = usb_hub_find_child(hcd->self.root_hub, port);
2186 	if (!udev) {
2187 		dev_err(hcd->self.controller, "No device attached to the RootHub\n");
2188 		return -ENODEV;
2189 	}
2190 	buf = kmalloc(USB_DT_DEVICE_SIZE, GFP_KERNEL);
2191 	if (!buf)
2192 		return -ENOMEM;
2193 
2194 	dr = kmalloc_obj(struct usb_ctrlrequest);
2195 	if (!dr) {
2196 		kfree(buf);
2197 		return -ENOMEM;
2198 	}
2199 
2200 	/* Fill Setup packet for GetDescriptor */
2201 	dr->bRequestType = USB_DIR_IN;
2202 	dr->bRequest = USB_REQ_GET_DESCRIPTOR;
2203 	dr->wValue = cpu_to_le16(USB_DT_DEVICE << 8);
2204 	dr->wIndex = 0;
2205 	dr->wLength = cpu_to_le16(USB_DT_DEVICE_SIZE);
2206 	urb = request_single_step_set_feature_urb(udev, dr, buf, &done);
2207 	if (!urb)
2208 		goto cleanup;
2209 
2210 	/* Submit just the SETUP stage */
2211 	retval = hcd->driver->submit_single_step_set_feature(hcd, urb, 1);
2212 	if (retval)
2213 		goto out1;
2214 	if (!wait_for_completion_timeout(&done, msecs_to_jiffies(2000))) {
2215 		usb_kill_urb(urb);
2216 		retval = -ETIMEDOUT;
2217 		dev_err(hcd->self.controller,
2218 			"%s SETUP stage timed out on ep0\n", __func__);
2219 		goto out1;
2220 	}
2221 	msleep(15 * 1000);
2222 
2223 	/* Complete remaining DATA and STATUS stages using the same URB */
2224 	urb->status = -EINPROGRESS;
2225 	urb->transfer_flags &= ~URB_NO_TRANSFER_DMA_MAP;
2226 	usb_get_urb(urb);
2227 	atomic_inc(&urb->use_count);
2228 	atomic_inc(&urb->dev->urbnum);
2229 	if (map_urb_for_dma(hcd, urb, GFP_KERNEL)) {
2230 		usb_put_urb(urb);
2231 		goto out1;
2232 	}
2233 
2234 	retval = hcd->driver->submit_single_step_set_feature(hcd, urb, 0);
2235 	if (!retval && !wait_for_completion_timeout(&done,
2236 						msecs_to_jiffies(2000))) {
2237 		usb_kill_urb(urb);
2238 		retval = -ETIMEDOUT;
2239 		dev_err(hcd->self.controller,
2240 			"%s IN stage timed out on ep0\n", __func__);
2241 	}
2242 out1:
2243 	usb_free_urb(urb);
2244 cleanup:
2245 	kfree(dr);
2246 	kfree(buf);
2247 	return retval;
2248 }
2249 EXPORT_SYMBOL_GPL(ehset_single_step_set_feature);
2250 #endif /* CONFIG_USB_HCD_TEST_MODE */
2251 
2252 /*-------------------------------------------------------------------------*/
2253 
2254 #ifdef	CONFIG_PM
2255 
2256 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2257 {
2258 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2259 	int		status;
2260 	int		old_state = hcd->state;
2261 
2262 	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2263 			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2264 			rhdev->do_remote_wakeup);
2265 	if (HCD_DEAD(hcd)) {
2266 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2267 		return 0;
2268 	}
2269 
2270 	if (!hcd->driver->bus_suspend) {
2271 		status = -ENOENT;
2272 	} else {
2273 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2274 		hcd->state = HC_STATE_QUIESCING;
2275 		status = hcd->driver->bus_suspend(hcd);
2276 	}
2277 	if (status == 0) {
2278 		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2279 		hcd->state = HC_STATE_SUSPENDED;
2280 
2281 		if (!PMSG_IS_AUTO(msg))
2282 			usb_phy_roothub_suspend(hcd->self.sysdev,
2283 						hcd->phy_roothub);
2284 
2285 		/* Did we race with a root-hub wakeup event? */
2286 		if (rhdev->do_remote_wakeup) {
2287 			char	buffer[6];
2288 
2289 			status = hcd->driver->hub_status_data(hcd, buffer);
2290 			if (status != 0) {
2291 				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2292 				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2293 				status = -EBUSY;
2294 			}
2295 		}
2296 	} else {
2297 		spin_lock_irq(&hcd_root_hub_lock);
2298 		if (!HCD_DEAD(hcd)) {
2299 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2300 			hcd->state = old_state;
2301 		}
2302 		spin_unlock_irq(&hcd_root_hub_lock);
2303 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2304 				"suspend", status);
2305 	}
2306 	return status;
2307 }
2308 
2309 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2310 {
2311 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2312 	int		status;
2313 	int		old_state = hcd->state;
2314 
2315 	dev_dbg(&rhdev->dev, "usb %sresume\n",
2316 			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2317 	if (HCD_DEAD(hcd)) {
2318 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2319 		return 0;
2320 	}
2321 
2322 	if (!PMSG_IS_AUTO(msg)) {
2323 		status = usb_phy_roothub_resume(hcd->self.sysdev,
2324 						hcd->phy_roothub);
2325 		if (status)
2326 			return status;
2327 	}
2328 
2329 	if (!hcd->driver->bus_resume)
2330 		return -ENOENT;
2331 	if (HCD_RH_RUNNING(hcd))
2332 		return 0;
2333 
2334 	hcd->state = HC_STATE_RESUMING;
2335 	status = hcd->driver->bus_resume(hcd);
2336 	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2337 	if (status == 0)
2338 		status = usb_phy_roothub_calibrate(hcd->phy_roothub);
2339 
2340 	if (status == 0) {
2341 		struct usb_device *udev;
2342 		int port1;
2343 
2344 		spin_lock_irq(&hcd_root_hub_lock);
2345 		if (!HCD_DEAD(hcd)) {
2346 			usb_set_device_state(rhdev, rhdev->actconfig
2347 					? USB_STATE_CONFIGURED
2348 					: USB_STATE_ADDRESS);
2349 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2350 			hcd->state = HC_STATE_RUNNING;
2351 		}
2352 		spin_unlock_irq(&hcd_root_hub_lock);
2353 
2354 		/*
2355 		 * Check whether any of the enabled ports on the root hub are
2356 		 * unsuspended.  If they are then a TRSMRCY delay is needed
2357 		 * (this is what the USB-2 spec calls a "global resume").
2358 		 * Otherwise we can skip the delay.
2359 		 */
2360 		usb_hub_for_each_child(rhdev, port1, udev) {
2361 			if (udev->state != USB_STATE_NOTATTACHED &&
2362 					!udev->port_is_suspended) {
2363 				usleep_range(10000, 11000);	/* TRSMRCY */
2364 				break;
2365 			}
2366 		}
2367 	} else {
2368 		hcd->state = old_state;
2369 		usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub);
2370 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2371 				"resume", status);
2372 		if (status != -ESHUTDOWN)
2373 			usb_hc_died(hcd);
2374 	}
2375 	return status;
2376 }
2377 
2378 /* Workqueue routine for root-hub remote wakeup */
2379 static void hcd_resume_work(struct work_struct *work)
2380 {
2381 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2382 	struct usb_device *udev = hcd->self.root_hub;
2383 
2384 	usb_remote_wakeup(udev);
2385 }
2386 
2387 /**
2388  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2389  * @hcd: host controller for this root hub
2390  *
2391  * The USB host controller calls this function when its root hub is
2392  * suspended (with the remote wakeup feature enabled) and a remote
2393  * wakeup request is received.  The routine submits a workqueue request
2394  * to resume the root hub (that is, manage its downstream ports again).
2395  */
2396 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2397 {
2398 	unsigned long flags;
2399 
2400 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2401 	if (hcd->rh_registered) {
2402 		pm_wakeup_event(&hcd->self.root_hub->dev, 0);
2403 		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2404 		queue_work(system_freezable_wq, &hcd->wakeup_work);
2405 	}
2406 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2407 }
2408 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2409 
2410 #endif	/* CONFIG_PM */
2411 
2412 /*-------------------------------------------------------------------------*/
2413 
2414 #ifdef	CONFIG_USB_OTG
2415 
2416 /**
2417  * usb_bus_start_enum - start immediate enumeration (for OTG)
2418  * @bus: the bus (must use hcd framework)
2419  * @port_num: 1-based number of port; usually bus->otg_port
2420  * Context: atomic
2421  *
2422  * Starts enumeration, with an immediate reset followed later by
2423  * hub_wq identifying and possibly configuring the device.
2424  * This is needed by OTG controller drivers, where it helps meet
2425  * HNP protocol timing requirements for starting a port reset.
2426  *
2427  * Return: 0 if successful.
2428  */
2429 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2430 {
2431 	struct usb_hcd		*hcd;
2432 	int			status = -EOPNOTSUPP;
2433 
2434 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2435 	 * boards with root hubs hooked up to internal devices (instead of
2436 	 * just the OTG port) may need more attention to resetting...
2437 	 */
2438 	hcd = bus_to_hcd(bus);
2439 	if (port_num && hcd->driver->start_port_reset)
2440 		status = hcd->driver->start_port_reset(hcd, port_num);
2441 
2442 	/* allocate hub_wq shortly after (first) root port reset finishes;
2443 	 * it may issue others, until at least 50 msecs have passed.
2444 	 */
2445 	if (status == 0)
2446 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2447 	return status;
2448 }
2449 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2450 
2451 #endif
2452 
2453 /*-------------------------------------------------------------------------*/
2454 
2455 /**
2456  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2457  * @irq: the IRQ being raised
2458  * @__hcd: pointer to the HCD whose IRQ is being signaled
2459  *
2460  * If the controller isn't HALTed, calls the driver's irq handler.
2461  * Checks whether the controller is now dead.
2462  *
2463  * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2464  */
2465 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2466 {
2467 	struct usb_hcd		*hcd = __hcd;
2468 	irqreturn_t		rc;
2469 
2470 	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2471 		rc = IRQ_NONE;
2472 	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2473 		rc = IRQ_NONE;
2474 	else
2475 		rc = IRQ_HANDLED;
2476 
2477 	return rc;
2478 }
2479 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2480 
2481 /*-------------------------------------------------------------------------*/
2482 
2483 /* Workqueue routine for when the root-hub has died. */
2484 static void hcd_died_work(struct work_struct *work)
2485 {
2486 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, died_work);
2487 	static char *env[] = {
2488 		"ERROR=DEAD",
2489 		NULL
2490 	};
2491 
2492 	/* Notify user space that the host controller has died */
2493 	kobject_uevent_env(&hcd->self.root_hub->dev.kobj, KOBJ_OFFLINE, env);
2494 }
2495 
2496 /**
2497  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2498  * @hcd: pointer to the HCD representing the controller
2499  *
2500  * This is called by bus glue to report a USB host controller that died
2501  * while operations may still have been pending.  It's called automatically
2502  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2503  *
2504  * Only call this function with the primary HCD.
2505  */
2506 void usb_hc_died (struct usb_hcd *hcd)
2507 {
2508 	unsigned long flags;
2509 
2510 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2511 
2512 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2513 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2514 	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2515 	if (hcd->rh_registered) {
2516 		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2517 
2518 		/* make hub_wq clean up old urbs and devices */
2519 		usb_set_device_state (hcd->self.root_hub,
2520 				USB_STATE_NOTATTACHED);
2521 		usb_kick_hub_wq(hcd->self.root_hub);
2522 	}
2523 	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2524 		hcd = hcd->shared_hcd;
2525 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2526 		set_bit(HCD_FLAG_DEAD, &hcd->flags);
2527 		if (hcd->rh_registered) {
2528 			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2529 
2530 			/* make hub_wq clean up old urbs and devices */
2531 			usb_set_device_state(hcd->self.root_hub,
2532 					USB_STATE_NOTATTACHED);
2533 			usb_kick_hub_wq(hcd->self.root_hub);
2534 		}
2535 	}
2536 
2537 	/* Handle the case where this function gets called with a shared HCD */
2538 	if (usb_hcd_is_primary_hcd(hcd))
2539 		schedule_work(&hcd->died_work);
2540 	else
2541 		schedule_work(&hcd->primary_hcd->died_work);
2542 
2543 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2544 	/* Make sure that the other roothub is also deallocated. */
2545 }
2546 EXPORT_SYMBOL_GPL (usb_hc_died);
2547 
2548 /*-------------------------------------------------------------------------*/
2549 
2550 static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2551 {
2552 
2553 	spin_lock_init(&bh->lock);
2554 	INIT_LIST_HEAD(&bh->head);
2555 	INIT_WORK(&bh->bh, usb_giveback_urb_bh);
2556 }
2557 
2558 struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
2559 		struct device *sysdev, struct device *dev, const char *bus_name,
2560 		struct usb_hcd *primary_hcd)
2561 {
2562 	struct usb_hcd *hcd;
2563 
2564 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2565 	if (!hcd)
2566 		return NULL;
2567 	if (primary_hcd == NULL) {
2568 		hcd->address0_mutex = kmalloc_obj(*hcd->address0_mutex);
2569 		if (!hcd->address0_mutex) {
2570 			kfree(hcd);
2571 			dev_dbg(dev, "hcd address0 mutex alloc failed\n");
2572 			return NULL;
2573 		}
2574 		mutex_init(hcd->address0_mutex);
2575 		hcd->bandwidth_mutex = kmalloc_obj(*hcd->bandwidth_mutex);
2576 		if (!hcd->bandwidth_mutex) {
2577 			kfree(hcd->address0_mutex);
2578 			kfree(hcd);
2579 			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2580 			return NULL;
2581 		}
2582 		mutex_init(hcd->bandwidth_mutex);
2583 		dev_set_drvdata(dev, hcd);
2584 	} else {
2585 		mutex_lock(&usb_port_peer_mutex);
2586 		hcd->address0_mutex = primary_hcd->address0_mutex;
2587 		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2588 		hcd->primary_hcd = primary_hcd;
2589 		primary_hcd->primary_hcd = primary_hcd;
2590 		hcd->shared_hcd = primary_hcd;
2591 		primary_hcd->shared_hcd = hcd;
2592 		mutex_unlock(&usb_port_peer_mutex);
2593 	}
2594 
2595 	kref_init(&hcd->kref);
2596 
2597 	usb_bus_init(&hcd->self);
2598 	hcd->self.controller = dev;
2599 	hcd->self.sysdev = sysdev;
2600 	hcd->self.bus_name = bus_name;
2601 
2602 	timer_setup(&hcd->rh_timer, rh_timer_func, 0);
2603 #ifdef CONFIG_PM
2604 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2605 #endif
2606 
2607 	INIT_WORK(&hcd->died_work, hcd_died_work);
2608 
2609 	hcd->driver = driver;
2610 	hcd->speed = driver->flags & HCD_MASK;
2611 	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2612 			"USB Host Controller";
2613 	return hcd;
2614 }
2615 EXPORT_SYMBOL_GPL(__usb_create_hcd);
2616 
2617 /**
2618  * usb_create_shared_hcd - create and initialize an HCD structure
2619  * @driver: HC driver that will use this hcd
2620  * @dev: device for this HC, stored in hcd->self.controller
2621  * @bus_name: value to store in hcd->self.bus_name
2622  * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2623  *              PCI device.  Only allocate certain resources for the primary HCD
2624  *
2625  * Context: task context, might sleep.
2626  *
2627  * Allocate a struct usb_hcd, with extra space at the end for the
2628  * HC driver's private data.  Initialize the generic members of the
2629  * hcd structure.
2630  *
2631  * Return: On success, a pointer to the created and initialized HCD structure.
2632  * On failure (e.g. if memory is unavailable), %NULL.
2633  */
2634 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2635 		struct device *dev, const char *bus_name,
2636 		struct usb_hcd *primary_hcd)
2637 {
2638 	return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd);
2639 }
2640 EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2641 
2642 /**
2643  * usb_create_hcd - create and initialize an HCD structure
2644  * @driver: HC driver that will use this hcd
2645  * @dev: device for this HC, stored in hcd->self.controller
2646  * @bus_name: value to store in hcd->self.bus_name
2647  *
2648  * Context: task context, might sleep.
2649  *
2650  * Allocate a struct usb_hcd, with extra space at the end for the
2651  * HC driver's private data.  Initialize the generic members of the
2652  * hcd structure.
2653  *
2654  * Return: On success, a pointer to the created and initialized HCD
2655  * structure. On failure (e.g. if memory is unavailable), %NULL.
2656  */
2657 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2658 		struct device *dev, const char *bus_name)
2659 {
2660 	return __usb_create_hcd(driver, dev, dev, bus_name, NULL);
2661 }
2662 EXPORT_SYMBOL_GPL(usb_create_hcd);
2663 
2664 /*
2665  * Roothubs that share one PCI device must also share the bandwidth mutex.
2666  * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2667  * deallocated.
2668  *
2669  * Make sure to deallocate the bandwidth_mutex only when the last HCD is
2670  * freed.  When hcd_release() is called for either hcd in a peer set,
2671  * invalidate the peer's ->shared_hcd and ->primary_hcd pointers.
2672  */
2673 static void hcd_release(struct kref *kref)
2674 {
2675 	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2676 
2677 	mutex_lock(&usb_port_peer_mutex);
2678 	if (hcd->shared_hcd) {
2679 		struct usb_hcd *peer = hcd->shared_hcd;
2680 
2681 		peer->shared_hcd = NULL;
2682 		peer->primary_hcd = NULL;
2683 	} else {
2684 		kfree(hcd->address0_mutex);
2685 		kfree(hcd->bandwidth_mutex);
2686 	}
2687 	mutex_unlock(&usb_port_peer_mutex);
2688 	kfree(hcd);
2689 }
2690 
2691 struct usb_hcd *usb_get_hcd(struct usb_hcd *hcd)
2692 {
2693 	if (hcd)
2694 		kref_get(&hcd->kref);
2695 	return hcd;
2696 }
2697 EXPORT_SYMBOL_GPL(usb_get_hcd);
2698 
2699 void usb_put_hcd(struct usb_hcd *hcd)
2700 {
2701 	if (hcd)
2702 		kref_put(&hcd->kref, hcd_release);
2703 }
2704 EXPORT_SYMBOL_GPL(usb_put_hcd);
2705 
2706 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2707 {
2708 	if (!hcd->primary_hcd)
2709 		return 1;
2710 	return hcd == hcd->primary_hcd;
2711 }
2712 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2713 
2714 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2715 {
2716 	if (!hcd->driver->find_raw_port_number)
2717 		return port1;
2718 
2719 	return hcd->driver->find_raw_port_number(hcd, port1);
2720 }
2721 
2722 static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2723 		unsigned int irqnum, unsigned long irqflags)
2724 {
2725 	int retval;
2726 
2727 	if (hcd->driver->irq) {
2728 
2729 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2730 				hcd->driver->description, hcd->self.busnum);
2731 		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2732 				hcd->irq_descr, hcd);
2733 		if (retval != 0) {
2734 			dev_err(hcd->self.controller,
2735 					"request interrupt %d failed\n",
2736 					irqnum);
2737 			return retval;
2738 		}
2739 		hcd->irq = irqnum;
2740 		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2741 				(hcd->driver->flags & HCD_MEMORY) ?
2742 					"io mem" : "io port",
2743 				(unsigned long long)hcd->rsrc_start);
2744 	} else {
2745 		hcd->irq = 0;
2746 		if (hcd->rsrc_start)
2747 			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2748 					(hcd->driver->flags & HCD_MEMORY) ?
2749 						"io mem" : "io port",
2750 					(unsigned long long)hcd->rsrc_start);
2751 	}
2752 	return 0;
2753 }
2754 
2755 /*
2756  * Before we free this root hub, flush in-flight peering attempts
2757  * and disable peer lookups
2758  */
2759 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2760 {
2761 	struct usb_device *rhdev;
2762 
2763 	mutex_lock(&usb_port_peer_mutex);
2764 	rhdev = hcd->self.root_hub;
2765 	hcd->self.root_hub = NULL;
2766 	mutex_unlock(&usb_port_peer_mutex);
2767 	usb_put_dev(rhdev);
2768 }
2769 
2770 /**
2771  * usb_stop_hcd - Halt the HCD
2772  * @hcd: the usb_hcd that has to be halted
2773  *
2774  * Stop the root-hub polling timer and invoke the HCD's ->stop callback.
2775  */
2776 static void usb_stop_hcd(struct usb_hcd *hcd)
2777 {
2778 	hcd->rh_pollable = 0;
2779 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2780 	timer_delete_sync(&hcd->rh_timer);
2781 
2782 	hcd->driver->stop(hcd);
2783 	hcd->state = HC_STATE_HALT;
2784 
2785 	/* In case the HCD restarted the timer, stop it again. */
2786 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2787 	timer_delete_sync(&hcd->rh_timer);
2788 }
2789 
2790 /**
2791  * usb_add_hcd - finish generic HCD structure initialization and register
2792  * @hcd: the usb_hcd structure to initialize
2793  * @irqnum: Interrupt line to allocate
2794  * @irqflags: Interrupt type flags
2795  *
2796  * Finish the remaining parts of generic HCD initialization: allocate the
2797  * buffers of consistent memory, register the bus, request the IRQ line,
2798  * and call the driver's reset() and start() routines.
2799  */
2800 int usb_add_hcd(struct usb_hcd *hcd,
2801 		unsigned int irqnum, unsigned long irqflags)
2802 {
2803 	int retval;
2804 	struct usb_device *rhdev;
2805 	struct usb_hcd *shared_hcd;
2806 	int skip_phy_initialization;
2807 
2808 	if (usb_hcd_is_primary_hcd(hcd))
2809 		skip_phy_initialization = hcd->skip_phy_initialization;
2810 	else
2811 		skip_phy_initialization = hcd->primary_hcd->skip_phy_initialization;
2812 
2813 	if (!skip_phy_initialization) {
2814 		if (usb_hcd_is_primary_hcd(hcd)) {
2815 			hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev);
2816 			if (IS_ERR(hcd->phy_roothub))
2817 				return PTR_ERR(hcd->phy_roothub);
2818 		} else {
2819 			hcd->phy_roothub = usb_phy_roothub_alloc_usb3_phy(hcd->self.sysdev);
2820 			if (IS_ERR(hcd->phy_roothub))
2821 				return PTR_ERR(hcd->phy_roothub);
2822 		}
2823 
2824 		retval = usb_phy_roothub_init(hcd->phy_roothub);
2825 		if (retval)
2826 			return retval;
2827 
2828 		retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2829 						  PHY_MODE_USB_HOST_SS);
2830 		if (retval)
2831 			retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2832 							  PHY_MODE_USB_HOST);
2833 		if (retval)
2834 			goto err_usb_phy_roothub_power_on;
2835 
2836 		retval = usb_phy_roothub_power_on(hcd->phy_roothub);
2837 		if (retval)
2838 			goto err_usb_phy_roothub_power_on;
2839 	}
2840 
2841 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2842 
2843 	switch (authorized_default) {
2844 	case USB_AUTHORIZE_NONE:
2845 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_NONE;
2846 		break;
2847 
2848 	case USB_AUTHORIZE_INTERNAL:
2849 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_INTERNAL;
2850 		break;
2851 
2852 	case USB_AUTHORIZE_ALL:
2853 	case USB_AUTHORIZE_WIRED:
2854 	default:
2855 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_ALL;
2856 		break;
2857 	}
2858 
2859 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2860 
2861 	/* per default all interfaces are authorized */
2862 	set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
2863 
2864 	/* HC is in reset state, but accessible.  Now do the one-time init,
2865 	 * bottom up so that hcds can customize the root hubs before hub_wq
2866 	 * starts talking to them.  (Note, bus id is assigned early too.)
2867 	 */
2868 	retval = hcd_buffer_create(hcd);
2869 	if (retval != 0) {
2870 		dev_dbg(hcd->self.sysdev, "pool alloc failed\n");
2871 		goto err_create_buf;
2872 	}
2873 
2874 	retval = usb_register_bus(&hcd->self);
2875 	if (retval < 0)
2876 		goto err_register_bus;
2877 
2878 	rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2879 	if (rhdev == NULL) {
2880 		dev_err(hcd->self.sysdev, "unable to allocate root hub\n");
2881 		retval = -ENOMEM;
2882 		goto err_allocate_root_hub;
2883 	}
2884 	mutex_lock(&usb_port_peer_mutex);
2885 	hcd->self.root_hub = rhdev;
2886 	mutex_unlock(&usb_port_peer_mutex);
2887 
2888 	rhdev->rx_lanes = 1;
2889 	rhdev->tx_lanes = 1;
2890 	rhdev->ssp_rate = USB_SSP_GEN_UNKNOWN;
2891 
2892 	switch (hcd->speed) {
2893 	case HCD_USB11:
2894 		rhdev->speed = USB_SPEED_FULL;
2895 		break;
2896 	case HCD_USB2:
2897 		rhdev->speed = USB_SPEED_HIGH;
2898 		break;
2899 	case HCD_USB3:
2900 		rhdev->speed = USB_SPEED_SUPER;
2901 		break;
2902 	case HCD_USB32:
2903 		rhdev->rx_lanes = 2;
2904 		rhdev->tx_lanes = 2;
2905 		rhdev->ssp_rate = USB_SSP_GEN_2x2;
2906 		rhdev->speed = USB_SPEED_SUPER_PLUS;
2907 		break;
2908 	case HCD_USB31:
2909 		rhdev->ssp_rate = USB_SSP_GEN_2x1;
2910 		rhdev->speed = USB_SPEED_SUPER_PLUS;
2911 		break;
2912 	default:
2913 		retval = -EINVAL;
2914 		goto err_set_rh_speed;
2915 	}
2916 
2917 	/* wakeup flag init defaults to "everything works" for root hubs,
2918 	 * but drivers can override it in reset() if needed, along with
2919 	 * recording the overall controller's system wakeup capability.
2920 	 */
2921 	device_set_wakeup_capable(&rhdev->dev, 1);
2922 
2923 	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2924 	 * registered.  But since the controller can die at any time,
2925 	 * let's initialize the flag before touching the hardware.
2926 	 */
2927 	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2928 
2929 	/* "reset" is misnamed; its role is now one-time init. the controller
2930 	 * should already have been reset (and boot firmware kicked off etc).
2931 	 */
2932 	if (hcd->driver->reset) {
2933 		retval = hcd->driver->reset(hcd);
2934 		if (retval < 0) {
2935 			dev_err(hcd->self.controller, "can't setup: %d\n",
2936 					retval);
2937 			goto err_hcd_driver_setup;
2938 		}
2939 	}
2940 	hcd->rh_pollable = 1;
2941 
2942 	retval = usb_phy_roothub_calibrate(hcd->phy_roothub);
2943 	if (retval)
2944 		goto err_hcd_driver_setup;
2945 
2946 	/* NOTE: root hub and controller capabilities may not be the same */
2947 	if (device_can_wakeup(hcd->self.controller)
2948 			&& device_can_wakeup(&hcd->self.root_hub->dev))
2949 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2950 
2951 	/* initialize BHs */
2952 	init_giveback_urb_bh(&hcd->high_prio_bh);
2953 	hcd->high_prio_bh.high_prio = true;
2954 	init_giveback_urb_bh(&hcd->low_prio_bh);
2955 
2956 	/* enable irqs just before we start the controller,
2957 	 * if the BIOS provides legacy PCI irqs.
2958 	 */
2959 	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2960 		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2961 		if (retval)
2962 			goto err_request_irq;
2963 	}
2964 
2965 	hcd->state = HC_STATE_RUNNING;
2966 	retval = hcd->driver->start(hcd);
2967 	if (retval < 0) {
2968 		dev_err(hcd->self.controller, "startup error %d\n", retval);
2969 		goto err_hcd_driver_start;
2970 	}
2971 
2972 	/* starting here, usbcore will pay attention to the shared HCD roothub */
2973 	shared_hcd = hcd->shared_hcd;
2974 	if (!usb_hcd_is_primary_hcd(hcd) && shared_hcd && HCD_DEFER_RH_REGISTER(shared_hcd)) {
2975 		retval = register_root_hub(shared_hcd);
2976 		if (retval != 0)
2977 			goto err_register_root_hub;
2978 
2979 		if (shared_hcd->uses_new_polling && HCD_POLL_RH(shared_hcd))
2980 			usb_hcd_poll_rh_status(shared_hcd);
2981 	}
2982 
2983 	/* starting here, usbcore will pay attention to this root hub */
2984 	if (!HCD_DEFER_RH_REGISTER(hcd)) {
2985 		retval = register_root_hub(hcd);
2986 		if (retval != 0)
2987 			goto err_register_root_hub;
2988 
2989 		if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2990 			usb_hcd_poll_rh_status(hcd);
2991 	}
2992 
2993 	return retval;
2994 
2995 err_register_root_hub:
2996 	usb_stop_hcd(hcd);
2997 err_hcd_driver_start:
2998 	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2999 		free_irq(irqnum, hcd);
3000 err_request_irq:
3001 err_hcd_driver_setup:
3002 err_set_rh_speed:
3003 	usb_put_invalidate_rhdev(hcd);
3004 err_allocate_root_hub:
3005 	usb_deregister_bus(&hcd->self);
3006 err_register_bus:
3007 	hcd_buffer_destroy(hcd);
3008 err_create_buf:
3009 	usb_phy_roothub_power_off(hcd->phy_roothub);
3010 err_usb_phy_roothub_power_on:
3011 	usb_phy_roothub_exit(hcd->phy_roothub);
3012 
3013 	return retval;
3014 }
3015 EXPORT_SYMBOL_GPL(usb_add_hcd);
3016 
3017 /**
3018  * usb_remove_hcd - shutdown processing for generic HCDs
3019  * @hcd: the usb_hcd structure to remove
3020  *
3021  * Context: task context, might sleep.
3022  *
3023  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
3024  * invoking the HCD's stop() method.
3025  */
3026 void usb_remove_hcd(struct usb_hcd *hcd)
3027 {
3028 	struct usb_device *rhdev;
3029 	bool rh_registered;
3030 
3031 	if (!hcd) {
3032 		pr_debug("%s: hcd is NULL\n", __func__);
3033 		return;
3034 	}
3035 	rhdev = hcd->self.root_hub;
3036 
3037 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
3038 
3039 	usb_get_dev(rhdev);
3040 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
3041 	if (HC_IS_RUNNING (hcd->state))
3042 		hcd->state = HC_STATE_QUIESCING;
3043 
3044 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
3045 	spin_lock_irq (&hcd_root_hub_lock);
3046 	rh_registered = hcd->rh_registered;
3047 	hcd->rh_registered = 0;
3048 	spin_unlock_irq (&hcd_root_hub_lock);
3049 
3050 #ifdef CONFIG_PM
3051 	cancel_work_sync(&hcd->wakeup_work);
3052 #endif
3053 	cancel_work_sync(&hcd->died_work);
3054 
3055 	mutex_lock(&usb_bus_idr_lock);
3056 	if (rh_registered)
3057 		usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
3058 	mutex_unlock(&usb_bus_idr_lock);
3059 
3060 	/*
3061 	 * flush_work() isn't needed here because:
3062 	 * - driver's disconnect() called from usb_disconnect() should
3063 	 *   make sure its URBs are completed during the disconnect()
3064 	 *   callback
3065 	 *
3066 	 * - it is too late to run complete() here since driver may have
3067 	 *   been removed already now
3068 	 */
3069 
3070 	/* Prevent any more root-hub status calls from the timer.
3071 	 * The HCD might still restart the timer (if a port status change
3072 	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
3073 	 * the hub_status_data() callback.
3074 	 */
3075 	usb_stop_hcd(hcd);
3076 
3077 	if (usb_hcd_is_primary_hcd(hcd)) {
3078 		if (hcd->irq > 0)
3079 			free_irq(hcd->irq, hcd);
3080 	}
3081 
3082 	usb_deregister_bus(&hcd->self);
3083 	hcd_buffer_destroy(hcd);
3084 
3085 	usb_phy_roothub_power_off(hcd->phy_roothub);
3086 	usb_phy_roothub_exit(hcd->phy_roothub);
3087 
3088 	usb_put_invalidate_rhdev(hcd);
3089 	hcd->flags = 0;
3090 }
3091 EXPORT_SYMBOL_GPL(usb_remove_hcd);
3092 
3093 void
3094 usb_hcd_platform_shutdown(struct platform_device *dev)
3095 {
3096 	struct usb_hcd *hcd = platform_get_drvdata(dev);
3097 
3098 	/* No need for pm_runtime_put(), we're shutting down */
3099 	pm_runtime_get_sync(&dev->dev);
3100 
3101 	if (hcd->driver->shutdown)
3102 		hcd->driver->shutdown(hcd);
3103 }
3104 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
3105 
3106 int usb_hcd_setup_local_mem(struct usb_hcd *hcd, phys_addr_t phys_addr,
3107 			    dma_addr_t dma, size_t size)
3108 {
3109 	int err;
3110 	void *local_mem;
3111 
3112 	hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, 4,
3113 						  dev_to_node(hcd->self.sysdev),
3114 						  dev_name(hcd->self.sysdev));
3115 	if (IS_ERR(hcd->localmem_pool))
3116 		return PTR_ERR(hcd->localmem_pool);
3117 
3118 	/*
3119 	 * if a physical SRAM address was passed, map it, otherwise
3120 	 * allocate system memory as a buffer.
3121 	 */
3122 	if (phys_addr)
3123 		local_mem = devm_memremap(hcd->self.sysdev, phys_addr,
3124 					  size, MEMREMAP_WC);
3125 	else
3126 		local_mem = dmam_alloc_attrs(hcd->self.sysdev, size, &dma,
3127 					     GFP_KERNEL,
3128 					     DMA_ATTR_WRITE_COMBINE);
3129 
3130 	if (IS_ERR_OR_NULL(local_mem)) {
3131 		if (!local_mem)
3132 			return -ENOMEM;
3133 
3134 		return PTR_ERR(local_mem);
3135 	}
3136 
3137 	/*
3138 	 * Here we pass a dma_addr_t but the arg type is a phys_addr_t.
3139 	 * It's not backed by system memory and thus there's no kernel mapping
3140 	 * for it.
3141 	 */
3142 	err = gen_pool_add_virt(hcd->localmem_pool, (unsigned long)local_mem,
3143 				dma, size, dev_to_node(hcd->self.sysdev));
3144 	if (err < 0) {
3145 		dev_err(hcd->self.sysdev, "gen_pool_add_virt failed with %d\n",
3146 			err);
3147 		return err;
3148 	}
3149 
3150 	return 0;
3151 }
3152 EXPORT_SYMBOL_GPL(usb_hcd_setup_local_mem);
3153 
3154 /*-------------------------------------------------------------------------*/
3155 
3156 #if IS_ENABLED(CONFIG_USB_MON)
3157 
3158 const struct usb_mon_operations *mon_ops;
3159 
3160 /*
3161  * The registration is unlocked.
3162  * We do it this way because we do not want to lock in hot paths.
3163  *
3164  * Notice that the code is minimally error-proof. Because usbmon needs
3165  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
3166  */
3167 
3168 int usb_mon_register(const struct usb_mon_operations *ops)
3169 {
3170 
3171 	if (mon_ops)
3172 		return -EBUSY;
3173 
3174 	mon_ops = ops;
3175 	mb();
3176 	return 0;
3177 }
3178 EXPORT_SYMBOL_GPL (usb_mon_register);
3179 
3180 void usb_mon_deregister (void)
3181 {
3182 
3183 	if (mon_ops == NULL) {
3184 		printk(KERN_ERR "USB: monitor was not registered\n");
3185 		return;
3186 	}
3187 	mon_ops = NULL;
3188 	mb();
3189 }
3190 EXPORT_SYMBOL_GPL (usb_mon_deregister);
3191 
3192 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
3193