xref: /linux/drivers/usb/core/hcd.c (revision b8d312aa075f33282565467662c4628dae0a2aff)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright Linus Torvalds 1999
4  * (C) Copyright Johannes Erdfelt 1999-2001
5  * (C) Copyright Andreas Gal 1999
6  * (C) Copyright Gregory P. Smith 1999
7  * (C) Copyright Deti Fliegl 1999
8  * (C) Copyright Randy Dunlap 2000
9  * (C) Copyright David Brownell 2000-2002
10  */
11 
12 #include <linux/bcd.h>
13 #include <linux/module.h>
14 #include <linux/version.h>
15 #include <linux/kernel.h>
16 #include <linux/sched/task_stack.h>
17 #include <linux/slab.h>
18 #include <linux/completion.h>
19 #include <linux/utsname.h>
20 #include <linux/mm.h>
21 #include <asm/io.h>
22 #include <linux/device.h>
23 #include <linux/dma-mapping.h>
24 #include <linux/mutex.h>
25 #include <asm/irq.h>
26 #include <asm/byteorder.h>
27 #include <asm/unaligned.h>
28 #include <linux/platform_device.h>
29 #include <linux/workqueue.h>
30 #include <linux/pm_runtime.h>
31 #include <linux/types.h>
32 #include <linux/genalloc.h>
33 #include <linux/io.h>
34 
35 #include <linux/phy/phy.h>
36 #include <linux/usb.h>
37 #include <linux/usb/hcd.h>
38 #include <linux/usb/otg.h>
39 
40 #include "usb.h"
41 #include "phy.h"
42 
43 
44 /*-------------------------------------------------------------------------*/
45 
46 /*
47  * USB Host Controller Driver framework
48  *
49  * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
50  * HCD-specific behaviors/bugs.
51  *
52  * This does error checks, tracks devices and urbs, and delegates to a
53  * "hc_driver" only for code (and data) that really needs to know about
54  * hardware differences.  That includes root hub registers, i/o queues,
55  * and so on ... but as little else as possible.
56  *
57  * Shared code includes most of the "root hub" code (these are emulated,
58  * though each HC's hardware works differently) and PCI glue, plus request
59  * tracking overhead.  The HCD code should only block on spinlocks or on
60  * hardware handshaking; blocking on software events (such as other kernel
61  * threads releasing resources, or completing actions) is all generic.
62  *
63  * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
64  * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
65  * only by the hub driver ... and that neither should be seen or used by
66  * usb client device drivers.
67  *
68  * Contributors of ideas or unattributed patches include: David Brownell,
69  * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
70  *
71  * HISTORY:
72  * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
73  *		associated cleanup.  "usb_hcd" still != "usb_bus".
74  * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
75  */
76 
77 /*-------------------------------------------------------------------------*/
78 
79 /* Keep track of which host controller drivers are loaded */
80 unsigned long usb_hcds_loaded;
81 EXPORT_SYMBOL_GPL(usb_hcds_loaded);
82 
83 /* host controllers we manage */
84 DEFINE_IDR (usb_bus_idr);
85 EXPORT_SYMBOL_GPL (usb_bus_idr);
86 
87 /* used when allocating bus numbers */
88 #define USB_MAXBUS		64
89 
90 /* used when updating list of hcds */
91 DEFINE_MUTEX(usb_bus_idr_lock);	/* exported only for usbfs */
92 EXPORT_SYMBOL_GPL (usb_bus_idr_lock);
93 
94 /* used for controlling access to virtual root hubs */
95 static DEFINE_SPINLOCK(hcd_root_hub_lock);
96 
97 /* used when updating an endpoint's URB list */
98 static DEFINE_SPINLOCK(hcd_urb_list_lock);
99 
100 /* used to protect against unlinking URBs after the device is gone */
101 static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
102 
103 /* wait queue for synchronous unlinks */
104 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
105 
106 static inline int is_root_hub(struct usb_device *udev)
107 {
108 	return (udev->parent == NULL);
109 }
110 
111 /*-------------------------------------------------------------------------*/
112 
113 /*
114  * Sharable chunks of root hub code.
115  */
116 
117 /*-------------------------------------------------------------------------*/
118 #define KERNEL_REL	bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff))
119 #define KERNEL_VER	bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff))
120 
121 /* usb 3.1 root hub device descriptor */
122 static const u8 usb31_rh_dev_descriptor[18] = {
123 	0x12,       /*  __u8  bLength; */
124 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
125 	0x10, 0x03, /*  __le16 bcdUSB; v3.1 */
126 
127 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
128 	0x00,	    /*  __u8  bDeviceSubClass; */
129 	0x03,       /*  __u8  bDeviceProtocol; USB 3 hub */
130 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
131 
132 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
133 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
134 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
135 
136 	0x03,       /*  __u8  iManufacturer; */
137 	0x02,       /*  __u8  iProduct; */
138 	0x01,       /*  __u8  iSerialNumber; */
139 	0x01        /*  __u8  bNumConfigurations; */
140 };
141 
142 /* usb 3.0 root hub device descriptor */
143 static const u8 usb3_rh_dev_descriptor[18] = {
144 	0x12,       /*  __u8  bLength; */
145 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
146 	0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
147 
148 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
149 	0x00,	    /*  __u8  bDeviceSubClass; */
150 	0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
151 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
152 
153 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
154 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
155 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
156 
157 	0x03,       /*  __u8  iManufacturer; */
158 	0x02,       /*  __u8  iProduct; */
159 	0x01,       /*  __u8  iSerialNumber; */
160 	0x01        /*  __u8  bNumConfigurations; */
161 };
162 
163 /* usb 2.5 (wireless USB 1.0) root hub device descriptor */
164 static const u8 usb25_rh_dev_descriptor[18] = {
165 	0x12,       /*  __u8  bLength; */
166 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
167 	0x50, 0x02, /*  __le16 bcdUSB; v2.5 */
168 
169 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
170 	0x00,	    /*  __u8  bDeviceSubClass; */
171 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
172 	0xFF,       /*  __u8  bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */
173 
174 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
175 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
176 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
177 
178 	0x03,       /*  __u8  iManufacturer; */
179 	0x02,       /*  __u8  iProduct; */
180 	0x01,       /*  __u8  iSerialNumber; */
181 	0x01        /*  __u8  bNumConfigurations; */
182 };
183 
184 /* usb 2.0 root hub device descriptor */
185 static const u8 usb2_rh_dev_descriptor[18] = {
186 	0x12,       /*  __u8  bLength; */
187 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
188 	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
189 
190 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
191 	0x00,	    /*  __u8  bDeviceSubClass; */
192 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
193 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
194 
195 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
196 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
197 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
198 
199 	0x03,       /*  __u8  iManufacturer; */
200 	0x02,       /*  __u8  iProduct; */
201 	0x01,       /*  __u8  iSerialNumber; */
202 	0x01        /*  __u8  bNumConfigurations; */
203 };
204 
205 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
206 
207 /* usb 1.1 root hub device descriptor */
208 static const u8 usb11_rh_dev_descriptor[18] = {
209 	0x12,       /*  __u8  bLength; */
210 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
211 	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
212 
213 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
214 	0x00,	    /*  __u8  bDeviceSubClass; */
215 	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
216 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
217 
218 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
219 	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
220 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
221 
222 	0x03,       /*  __u8  iManufacturer; */
223 	0x02,       /*  __u8  iProduct; */
224 	0x01,       /*  __u8  iSerialNumber; */
225 	0x01        /*  __u8  bNumConfigurations; */
226 };
227 
228 
229 /*-------------------------------------------------------------------------*/
230 
231 /* Configuration descriptors for our root hubs */
232 
233 static const u8 fs_rh_config_descriptor[] = {
234 
235 	/* one configuration */
236 	0x09,       /*  __u8  bLength; */
237 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
238 	0x19, 0x00, /*  __le16 wTotalLength; */
239 	0x01,       /*  __u8  bNumInterfaces; (1) */
240 	0x01,       /*  __u8  bConfigurationValue; */
241 	0x00,       /*  __u8  iConfiguration; */
242 	0xc0,       /*  __u8  bmAttributes;
243 				 Bit 7: must be set,
244 				     6: Self-powered,
245 				     5: Remote wakeup,
246 				     4..0: resvd */
247 	0x00,       /*  __u8  MaxPower; */
248 
249 	/* USB 1.1:
250 	 * USB 2.0, single TT organization (mandatory):
251 	 *	one interface, protocol 0
252 	 *
253 	 * USB 2.0, multiple TT organization (optional):
254 	 *	two interfaces, protocols 1 (like single TT)
255 	 *	and 2 (multiple TT mode) ... config is
256 	 *	sometimes settable
257 	 *	NOT IMPLEMENTED
258 	 */
259 
260 	/* one interface */
261 	0x09,       /*  __u8  if_bLength; */
262 	USB_DT_INTERFACE,  /* __u8 if_bDescriptorType; Interface */
263 	0x00,       /*  __u8  if_bInterfaceNumber; */
264 	0x00,       /*  __u8  if_bAlternateSetting; */
265 	0x01,       /*  __u8  if_bNumEndpoints; */
266 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
267 	0x00,       /*  __u8  if_bInterfaceSubClass; */
268 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
269 	0x00,       /*  __u8  if_iInterface; */
270 
271 	/* one endpoint (status change endpoint) */
272 	0x07,       /*  __u8  ep_bLength; */
273 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
274 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
275 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
276 	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
277 	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
278 };
279 
280 static const u8 hs_rh_config_descriptor[] = {
281 
282 	/* one configuration */
283 	0x09,       /*  __u8  bLength; */
284 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
285 	0x19, 0x00, /*  __le16 wTotalLength; */
286 	0x01,       /*  __u8  bNumInterfaces; (1) */
287 	0x01,       /*  __u8  bConfigurationValue; */
288 	0x00,       /*  __u8  iConfiguration; */
289 	0xc0,       /*  __u8  bmAttributes;
290 				 Bit 7: must be set,
291 				     6: Self-powered,
292 				     5: Remote wakeup,
293 				     4..0: resvd */
294 	0x00,       /*  __u8  MaxPower; */
295 
296 	/* USB 1.1:
297 	 * USB 2.0, single TT organization (mandatory):
298 	 *	one interface, protocol 0
299 	 *
300 	 * USB 2.0, multiple TT organization (optional):
301 	 *	two interfaces, protocols 1 (like single TT)
302 	 *	and 2 (multiple TT mode) ... config is
303 	 *	sometimes settable
304 	 *	NOT IMPLEMENTED
305 	 */
306 
307 	/* one interface */
308 	0x09,       /*  __u8  if_bLength; */
309 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
310 	0x00,       /*  __u8  if_bInterfaceNumber; */
311 	0x00,       /*  __u8  if_bAlternateSetting; */
312 	0x01,       /*  __u8  if_bNumEndpoints; */
313 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
314 	0x00,       /*  __u8  if_bInterfaceSubClass; */
315 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
316 	0x00,       /*  __u8  if_iInterface; */
317 
318 	/* one endpoint (status change endpoint) */
319 	0x07,       /*  __u8  ep_bLength; */
320 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
321 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
322 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
323 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
324 		     * see hub.c:hub_configure() for details. */
325 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
326 	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
327 };
328 
329 static const u8 ss_rh_config_descriptor[] = {
330 	/* one configuration */
331 	0x09,       /*  __u8  bLength; */
332 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
333 	0x1f, 0x00, /*  __le16 wTotalLength; */
334 	0x01,       /*  __u8  bNumInterfaces; (1) */
335 	0x01,       /*  __u8  bConfigurationValue; */
336 	0x00,       /*  __u8  iConfiguration; */
337 	0xc0,       /*  __u8  bmAttributes;
338 				 Bit 7: must be set,
339 				     6: Self-powered,
340 				     5: Remote wakeup,
341 				     4..0: resvd */
342 	0x00,       /*  __u8  MaxPower; */
343 
344 	/* one interface */
345 	0x09,       /*  __u8  if_bLength; */
346 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
347 	0x00,       /*  __u8  if_bInterfaceNumber; */
348 	0x00,       /*  __u8  if_bAlternateSetting; */
349 	0x01,       /*  __u8  if_bNumEndpoints; */
350 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
351 	0x00,       /*  __u8  if_bInterfaceSubClass; */
352 	0x00,       /*  __u8  if_bInterfaceProtocol; */
353 	0x00,       /*  __u8  if_iInterface; */
354 
355 	/* one endpoint (status change endpoint) */
356 	0x07,       /*  __u8  ep_bLength; */
357 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
358 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
359 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
360 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
361 		     * see hub.c:hub_configure() for details. */
362 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
363 	0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
364 
365 	/* one SuperSpeed endpoint companion descriptor */
366 	0x06,        /* __u8 ss_bLength */
367 	USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */
368 		     /* Companion */
369 	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
370 	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
371 	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
372 };
373 
374 /* authorized_default behaviour:
375  * -1 is authorized for all devices except wireless (old behaviour)
376  * 0 is unauthorized for all devices
377  * 1 is authorized for all devices
378  * 2 is authorized for internal devices
379  */
380 #define USB_AUTHORIZE_WIRED	-1
381 #define USB_AUTHORIZE_NONE	0
382 #define USB_AUTHORIZE_ALL	1
383 #define USB_AUTHORIZE_INTERNAL	2
384 
385 static int authorized_default = USB_AUTHORIZE_WIRED;
386 module_param(authorized_default, int, S_IRUGO|S_IWUSR);
387 MODULE_PARM_DESC(authorized_default,
388 		"Default USB device authorization: 0 is not authorized, 1 is "
389 		"authorized, 2 is authorized for internal devices, -1 is "
390 		"authorized except for wireless USB (default, old behaviour)");
391 /*-------------------------------------------------------------------------*/
392 
393 /**
394  * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
395  * @s: Null-terminated ASCII (actually ISO-8859-1) string
396  * @buf: Buffer for USB string descriptor (header + UTF-16LE)
397  * @len: Length (in bytes; may be odd) of descriptor buffer.
398  *
399  * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
400  * whichever is less.
401  *
402  * Note:
403  * USB String descriptors can contain at most 126 characters; input
404  * strings longer than that are truncated.
405  */
406 static unsigned
407 ascii2desc(char const *s, u8 *buf, unsigned len)
408 {
409 	unsigned n, t = 2 + 2*strlen(s);
410 
411 	if (t > 254)
412 		t = 254;	/* Longest possible UTF string descriptor */
413 	if (len > t)
414 		len = t;
415 
416 	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
417 
418 	n = len;
419 	while (n--) {
420 		*buf++ = t;
421 		if (!n--)
422 			break;
423 		*buf++ = t >> 8;
424 		t = (unsigned char)*s++;
425 	}
426 	return len;
427 }
428 
429 /**
430  * rh_string() - provides string descriptors for root hub
431  * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
432  * @hcd: the host controller for this root hub
433  * @data: buffer for output packet
434  * @len: length of the provided buffer
435  *
436  * Produces either a manufacturer, product or serial number string for the
437  * virtual root hub device.
438  *
439  * Return: The number of bytes filled in: the length of the descriptor or
440  * of the provided buffer, whichever is less.
441  */
442 static unsigned
443 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
444 {
445 	char buf[100];
446 	char const *s;
447 	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
448 
449 	/* language ids */
450 	switch (id) {
451 	case 0:
452 		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
453 		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
454 		if (len > 4)
455 			len = 4;
456 		memcpy(data, langids, len);
457 		return len;
458 	case 1:
459 		/* Serial number */
460 		s = hcd->self.bus_name;
461 		break;
462 	case 2:
463 		/* Product name */
464 		s = hcd->product_desc;
465 		break;
466 	case 3:
467 		/* Manufacturer */
468 		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
469 			init_utsname()->release, hcd->driver->description);
470 		s = buf;
471 		break;
472 	default:
473 		/* Can't happen; caller guarantees it */
474 		return 0;
475 	}
476 
477 	return ascii2desc(s, data, len);
478 }
479 
480 
481 /* Root hub control transfers execute synchronously */
482 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
483 {
484 	struct usb_ctrlrequest *cmd;
485 	u16		typeReq, wValue, wIndex, wLength;
486 	u8		*ubuf = urb->transfer_buffer;
487 	unsigned	len = 0;
488 	int		status;
489 	u8		patch_wakeup = 0;
490 	u8		patch_protocol = 0;
491 	u16		tbuf_size;
492 	u8		*tbuf = NULL;
493 	const u8	*bufp;
494 
495 	might_sleep();
496 
497 	spin_lock_irq(&hcd_root_hub_lock);
498 	status = usb_hcd_link_urb_to_ep(hcd, urb);
499 	spin_unlock_irq(&hcd_root_hub_lock);
500 	if (status)
501 		return status;
502 	urb->hcpriv = hcd;	/* Indicate it's queued */
503 
504 	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
505 	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
506 	wValue   = le16_to_cpu (cmd->wValue);
507 	wIndex   = le16_to_cpu (cmd->wIndex);
508 	wLength  = le16_to_cpu (cmd->wLength);
509 
510 	if (wLength > urb->transfer_buffer_length)
511 		goto error;
512 
513 	/*
514 	 * tbuf should be at least as big as the
515 	 * USB hub descriptor.
516 	 */
517 	tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
518 	tbuf = kzalloc(tbuf_size, GFP_KERNEL);
519 	if (!tbuf) {
520 		status = -ENOMEM;
521 		goto err_alloc;
522 	}
523 
524 	bufp = tbuf;
525 
526 
527 	urb->actual_length = 0;
528 	switch (typeReq) {
529 
530 	/* DEVICE REQUESTS */
531 
532 	/* The root hub's remote wakeup enable bit is implemented using
533 	 * driver model wakeup flags.  If this system supports wakeup
534 	 * through USB, userspace may change the default "allow wakeup"
535 	 * policy through sysfs or these calls.
536 	 *
537 	 * Most root hubs support wakeup from downstream devices, for
538 	 * runtime power management (disabling USB clocks and reducing
539 	 * VBUS power usage).  However, not all of them do so; silicon,
540 	 * board, and BIOS bugs here are not uncommon, so these can't
541 	 * be treated quite like external hubs.
542 	 *
543 	 * Likewise, not all root hubs will pass wakeup events upstream,
544 	 * to wake up the whole system.  So don't assume root hub and
545 	 * controller capabilities are identical.
546 	 */
547 
548 	case DeviceRequest | USB_REQ_GET_STATUS:
549 		tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
550 					<< USB_DEVICE_REMOTE_WAKEUP)
551 				| (1 << USB_DEVICE_SELF_POWERED);
552 		tbuf[1] = 0;
553 		len = 2;
554 		break;
555 	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
556 		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
557 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
558 		else
559 			goto error;
560 		break;
561 	case DeviceOutRequest | USB_REQ_SET_FEATURE:
562 		if (device_can_wakeup(&hcd->self.root_hub->dev)
563 				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
564 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
565 		else
566 			goto error;
567 		break;
568 	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
569 		tbuf[0] = 1;
570 		len = 1;
571 			/* FALLTHROUGH */
572 	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
573 		break;
574 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
575 		switch (wValue & 0xff00) {
576 		case USB_DT_DEVICE << 8:
577 			switch (hcd->speed) {
578 			case HCD_USB32:
579 			case HCD_USB31:
580 				bufp = usb31_rh_dev_descriptor;
581 				break;
582 			case HCD_USB3:
583 				bufp = usb3_rh_dev_descriptor;
584 				break;
585 			case HCD_USB25:
586 				bufp = usb25_rh_dev_descriptor;
587 				break;
588 			case HCD_USB2:
589 				bufp = usb2_rh_dev_descriptor;
590 				break;
591 			case HCD_USB11:
592 				bufp = usb11_rh_dev_descriptor;
593 				break;
594 			default:
595 				goto error;
596 			}
597 			len = 18;
598 			if (hcd->has_tt)
599 				patch_protocol = 1;
600 			break;
601 		case USB_DT_CONFIG << 8:
602 			switch (hcd->speed) {
603 			case HCD_USB32:
604 			case HCD_USB31:
605 			case HCD_USB3:
606 				bufp = ss_rh_config_descriptor;
607 				len = sizeof ss_rh_config_descriptor;
608 				break;
609 			case HCD_USB25:
610 			case HCD_USB2:
611 				bufp = hs_rh_config_descriptor;
612 				len = sizeof hs_rh_config_descriptor;
613 				break;
614 			case HCD_USB11:
615 				bufp = fs_rh_config_descriptor;
616 				len = sizeof fs_rh_config_descriptor;
617 				break;
618 			default:
619 				goto error;
620 			}
621 			if (device_can_wakeup(&hcd->self.root_hub->dev))
622 				patch_wakeup = 1;
623 			break;
624 		case USB_DT_STRING << 8:
625 			if ((wValue & 0xff) < 4)
626 				urb->actual_length = rh_string(wValue & 0xff,
627 						hcd, ubuf, wLength);
628 			else /* unsupported IDs --> "protocol stall" */
629 				goto error;
630 			break;
631 		case USB_DT_BOS << 8:
632 			goto nongeneric;
633 		default:
634 			goto error;
635 		}
636 		break;
637 	case DeviceRequest | USB_REQ_GET_INTERFACE:
638 		tbuf[0] = 0;
639 		len = 1;
640 			/* FALLTHROUGH */
641 	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
642 		break;
643 	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
644 		/* wValue == urb->dev->devaddr */
645 		dev_dbg (hcd->self.controller, "root hub device address %d\n",
646 			wValue);
647 		break;
648 
649 	/* INTERFACE REQUESTS (no defined feature/status flags) */
650 
651 	/* ENDPOINT REQUESTS */
652 
653 	case EndpointRequest | USB_REQ_GET_STATUS:
654 		/* ENDPOINT_HALT flag */
655 		tbuf[0] = 0;
656 		tbuf[1] = 0;
657 		len = 2;
658 			/* FALLTHROUGH */
659 	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
660 	case EndpointOutRequest | USB_REQ_SET_FEATURE:
661 		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
662 		break;
663 
664 	/* CLASS REQUESTS (and errors) */
665 
666 	default:
667 nongeneric:
668 		/* non-generic request */
669 		switch (typeReq) {
670 		case GetHubStatus:
671 			len = 4;
672 			break;
673 		case GetPortStatus:
674 			if (wValue == HUB_PORT_STATUS)
675 				len = 4;
676 			else
677 				/* other port status types return 8 bytes */
678 				len = 8;
679 			break;
680 		case GetHubDescriptor:
681 			len = sizeof (struct usb_hub_descriptor);
682 			break;
683 		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
684 			/* len is returned by hub_control */
685 			break;
686 		}
687 		status = hcd->driver->hub_control (hcd,
688 			typeReq, wValue, wIndex,
689 			tbuf, wLength);
690 
691 		if (typeReq == GetHubDescriptor)
692 			usb_hub_adjust_deviceremovable(hcd->self.root_hub,
693 				(struct usb_hub_descriptor *)tbuf);
694 		break;
695 error:
696 		/* "protocol stall" on error */
697 		status = -EPIPE;
698 	}
699 
700 	if (status < 0) {
701 		len = 0;
702 		if (status != -EPIPE) {
703 			dev_dbg (hcd->self.controller,
704 				"CTRL: TypeReq=0x%x val=0x%x "
705 				"idx=0x%x len=%d ==> %d\n",
706 				typeReq, wValue, wIndex,
707 				wLength, status);
708 		}
709 	} else if (status > 0) {
710 		/* hub_control may return the length of data copied. */
711 		len = status;
712 		status = 0;
713 	}
714 	if (len) {
715 		if (urb->transfer_buffer_length < len)
716 			len = urb->transfer_buffer_length;
717 		urb->actual_length = len;
718 		/* always USB_DIR_IN, toward host */
719 		memcpy (ubuf, bufp, len);
720 
721 		/* report whether RH hardware supports remote wakeup */
722 		if (patch_wakeup &&
723 				len > offsetof (struct usb_config_descriptor,
724 						bmAttributes))
725 			((struct usb_config_descriptor *)ubuf)->bmAttributes
726 				|= USB_CONFIG_ATT_WAKEUP;
727 
728 		/* report whether RH hardware has an integrated TT */
729 		if (patch_protocol &&
730 				len > offsetof(struct usb_device_descriptor,
731 						bDeviceProtocol))
732 			((struct usb_device_descriptor *) ubuf)->
733 				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
734 	}
735 
736 	kfree(tbuf);
737  err_alloc:
738 
739 	/* any errors get returned through the urb completion */
740 	spin_lock_irq(&hcd_root_hub_lock);
741 	usb_hcd_unlink_urb_from_ep(hcd, urb);
742 	usb_hcd_giveback_urb(hcd, urb, status);
743 	spin_unlock_irq(&hcd_root_hub_lock);
744 	return 0;
745 }
746 
747 /*-------------------------------------------------------------------------*/
748 
749 /*
750  * Root Hub interrupt transfers are polled using a timer if the
751  * driver requests it; otherwise the driver is responsible for
752  * calling usb_hcd_poll_rh_status() when an event occurs.
753  *
754  * Completions are called in_interrupt(), but they may or may not
755  * be in_irq().
756  */
757 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
758 {
759 	struct urb	*urb;
760 	int		length;
761 	unsigned long	flags;
762 	char		buffer[6];	/* Any root hubs with > 31 ports? */
763 
764 	if (unlikely(!hcd->rh_pollable))
765 		return;
766 	if (!hcd->uses_new_polling && !hcd->status_urb)
767 		return;
768 
769 	length = hcd->driver->hub_status_data(hcd, buffer);
770 	if (length > 0) {
771 
772 		/* try to complete the status urb */
773 		spin_lock_irqsave(&hcd_root_hub_lock, flags);
774 		urb = hcd->status_urb;
775 		if (urb) {
776 			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
777 			hcd->status_urb = NULL;
778 			urb->actual_length = length;
779 			memcpy(urb->transfer_buffer, buffer, length);
780 
781 			usb_hcd_unlink_urb_from_ep(hcd, urb);
782 			usb_hcd_giveback_urb(hcd, urb, 0);
783 		} else {
784 			length = 0;
785 			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
786 		}
787 		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
788 	}
789 
790 	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
791 	 * exceed that limit if HZ is 100. The math is more clunky than
792 	 * maybe expected, this is to make sure that all timers for USB devices
793 	 * fire at the same time to give the CPU a break in between */
794 	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
795 			(length == 0 && hcd->status_urb != NULL))
796 		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
797 }
798 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
799 
800 /* timer callback */
801 static void rh_timer_func (struct timer_list *t)
802 {
803 	struct usb_hcd *_hcd = from_timer(_hcd, t, rh_timer);
804 
805 	usb_hcd_poll_rh_status(_hcd);
806 }
807 
808 /*-------------------------------------------------------------------------*/
809 
810 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
811 {
812 	int		retval;
813 	unsigned long	flags;
814 	unsigned	len = 1 + (urb->dev->maxchild / 8);
815 
816 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
817 	if (hcd->status_urb || urb->transfer_buffer_length < len) {
818 		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
819 		retval = -EINVAL;
820 		goto done;
821 	}
822 
823 	retval = usb_hcd_link_urb_to_ep(hcd, urb);
824 	if (retval)
825 		goto done;
826 
827 	hcd->status_urb = urb;
828 	urb->hcpriv = hcd;	/* indicate it's queued */
829 	if (!hcd->uses_new_polling)
830 		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
831 
832 	/* If a status change has already occurred, report it ASAP */
833 	else if (HCD_POLL_PENDING(hcd))
834 		mod_timer(&hcd->rh_timer, jiffies);
835 	retval = 0;
836  done:
837 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
838 	return retval;
839 }
840 
841 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
842 {
843 	if (usb_endpoint_xfer_int(&urb->ep->desc))
844 		return rh_queue_status (hcd, urb);
845 	if (usb_endpoint_xfer_control(&urb->ep->desc))
846 		return rh_call_control (hcd, urb);
847 	return -EINVAL;
848 }
849 
850 /*-------------------------------------------------------------------------*/
851 
852 /* Unlinks of root-hub control URBs are legal, but they don't do anything
853  * since these URBs always execute synchronously.
854  */
855 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
856 {
857 	unsigned long	flags;
858 	int		rc;
859 
860 	spin_lock_irqsave(&hcd_root_hub_lock, flags);
861 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
862 	if (rc)
863 		goto done;
864 
865 	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
866 		;	/* Do nothing */
867 
868 	} else {				/* Status URB */
869 		if (!hcd->uses_new_polling)
870 			del_timer (&hcd->rh_timer);
871 		if (urb == hcd->status_urb) {
872 			hcd->status_urb = NULL;
873 			usb_hcd_unlink_urb_from_ep(hcd, urb);
874 			usb_hcd_giveback_urb(hcd, urb, status);
875 		}
876 	}
877  done:
878 	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
879 	return rc;
880 }
881 
882 
883 
884 /*
885  * Show & store the current value of authorized_default
886  */
887 static ssize_t authorized_default_show(struct device *dev,
888 				       struct device_attribute *attr, char *buf)
889 {
890 	struct usb_device *rh_usb_dev = to_usb_device(dev);
891 	struct usb_bus *usb_bus = rh_usb_dev->bus;
892 	struct usb_hcd *hcd;
893 
894 	hcd = bus_to_hcd(usb_bus);
895 	return snprintf(buf, PAGE_SIZE, "%u\n", hcd->dev_policy);
896 }
897 
898 static ssize_t authorized_default_store(struct device *dev,
899 					struct device_attribute *attr,
900 					const char *buf, size_t size)
901 {
902 	ssize_t result;
903 	unsigned val;
904 	struct usb_device *rh_usb_dev = to_usb_device(dev);
905 	struct usb_bus *usb_bus = rh_usb_dev->bus;
906 	struct usb_hcd *hcd;
907 
908 	hcd = bus_to_hcd(usb_bus);
909 	result = sscanf(buf, "%u\n", &val);
910 	if (result == 1) {
911 		hcd->dev_policy = val <= USB_DEVICE_AUTHORIZE_INTERNAL ?
912 			val : USB_DEVICE_AUTHORIZE_ALL;
913 		result = size;
914 	} else {
915 		result = -EINVAL;
916 	}
917 	return result;
918 }
919 static DEVICE_ATTR_RW(authorized_default);
920 
921 /*
922  * interface_authorized_default_show - show default authorization status
923  * for USB interfaces
924  *
925  * note: interface_authorized_default is the default value
926  *       for initializing the authorized attribute of interfaces
927  */
928 static ssize_t interface_authorized_default_show(struct device *dev,
929 		struct device_attribute *attr, char *buf)
930 {
931 	struct usb_device *usb_dev = to_usb_device(dev);
932 	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
933 
934 	return sprintf(buf, "%u\n", !!HCD_INTF_AUTHORIZED(hcd));
935 }
936 
937 /*
938  * interface_authorized_default_store - store default authorization status
939  * for USB interfaces
940  *
941  * note: interface_authorized_default is the default value
942  *       for initializing the authorized attribute of interfaces
943  */
944 static ssize_t interface_authorized_default_store(struct device *dev,
945 		struct device_attribute *attr, const char *buf, size_t count)
946 {
947 	struct usb_device *usb_dev = to_usb_device(dev);
948 	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
949 	int rc = count;
950 	bool val;
951 
952 	if (strtobool(buf, &val) != 0)
953 		return -EINVAL;
954 
955 	if (val)
956 		set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
957 	else
958 		clear_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
959 
960 	return rc;
961 }
962 static DEVICE_ATTR_RW(interface_authorized_default);
963 
964 /* Group all the USB bus attributes */
965 static struct attribute *usb_bus_attrs[] = {
966 		&dev_attr_authorized_default.attr,
967 		&dev_attr_interface_authorized_default.attr,
968 		NULL,
969 };
970 
971 static const struct attribute_group usb_bus_attr_group = {
972 	.name = NULL,	/* we want them in the same directory */
973 	.attrs = usb_bus_attrs,
974 };
975 
976 
977 
978 /*-------------------------------------------------------------------------*/
979 
980 /**
981  * usb_bus_init - shared initialization code
982  * @bus: the bus structure being initialized
983  *
984  * This code is used to initialize a usb_bus structure, memory for which is
985  * separately managed.
986  */
987 static void usb_bus_init (struct usb_bus *bus)
988 {
989 	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
990 
991 	bus->devnum_next = 1;
992 
993 	bus->root_hub = NULL;
994 	bus->busnum = -1;
995 	bus->bandwidth_allocated = 0;
996 	bus->bandwidth_int_reqs  = 0;
997 	bus->bandwidth_isoc_reqs = 0;
998 	mutex_init(&bus->devnum_next_mutex);
999 }
1000 
1001 /*-------------------------------------------------------------------------*/
1002 
1003 /**
1004  * usb_register_bus - registers the USB host controller with the usb core
1005  * @bus: pointer to the bus to register
1006  * Context: !in_interrupt()
1007  *
1008  * Assigns a bus number, and links the controller into usbcore data
1009  * structures so that it can be seen by scanning the bus list.
1010  *
1011  * Return: 0 if successful. A negative error code otherwise.
1012  */
1013 static int usb_register_bus(struct usb_bus *bus)
1014 {
1015 	int result = -E2BIG;
1016 	int busnum;
1017 
1018 	mutex_lock(&usb_bus_idr_lock);
1019 	busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL);
1020 	if (busnum < 0) {
1021 		pr_err("%s: failed to get bus number\n", usbcore_name);
1022 		goto error_find_busnum;
1023 	}
1024 	bus->busnum = busnum;
1025 	mutex_unlock(&usb_bus_idr_lock);
1026 
1027 	usb_notify_add_bus(bus);
1028 
1029 	dev_info (bus->controller, "new USB bus registered, assigned bus "
1030 		  "number %d\n", bus->busnum);
1031 	return 0;
1032 
1033 error_find_busnum:
1034 	mutex_unlock(&usb_bus_idr_lock);
1035 	return result;
1036 }
1037 
1038 /**
1039  * usb_deregister_bus - deregisters the USB host controller
1040  * @bus: pointer to the bus to deregister
1041  * Context: !in_interrupt()
1042  *
1043  * Recycles the bus number, and unlinks the controller from usbcore data
1044  * structures so that it won't be seen by scanning the bus list.
1045  */
1046 static void usb_deregister_bus (struct usb_bus *bus)
1047 {
1048 	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
1049 
1050 	/*
1051 	 * NOTE: make sure that all the devices are removed by the
1052 	 * controller code, as well as having it call this when cleaning
1053 	 * itself up
1054 	 */
1055 	mutex_lock(&usb_bus_idr_lock);
1056 	idr_remove(&usb_bus_idr, bus->busnum);
1057 	mutex_unlock(&usb_bus_idr_lock);
1058 
1059 	usb_notify_remove_bus(bus);
1060 }
1061 
1062 /**
1063  * register_root_hub - called by usb_add_hcd() to register a root hub
1064  * @hcd: host controller for this root hub
1065  *
1066  * This function registers the root hub with the USB subsystem.  It sets up
1067  * the device properly in the device tree and then calls usb_new_device()
1068  * to register the usb device.  It also assigns the root hub's USB address
1069  * (always 1).
1070  *
1071  * Return: 0 if successful. A negative error code otherwise.
1072  */
1073 static int register_root_hub(struct usb_hcd *hcd)
1074 {
1075 	struct device *parent_dev = hcd->self.controller;
1076 	struct usb_device *usb_dev = hcd->self.root_hub;
1077 	const int devnum = 1;
1078 	int retval;
1079 
1080 	usb_dev->devnum = devnum;
1081 	usb_dev->bus->devnum_next = devnum + 1;
1082 	set_bit (devnum, usb_dev->bus->devmap.devicemap);
1083 	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
1084 
1085 	mutex_lock(&usb_bus_idr_lock);
1086 
1087 	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
1088 	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
1089 	if (retval != sizeof usb_dev->descriptor) {
1090 		mutex_unlock(&usb_bus_idr_lock);
1091 		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
1092 				dev_name(&usb_dev->dev), retval);
1093 		return (retval < 0) ? retval : -EMSGSIZE;
1094 	}
1095 
1096 	if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
1097 		retval = usb_get_bos_descriptor(usb_dev);
1098 		if (!retval) {
1099 			usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
1100 		} else if (usb_dev->speed >= USB_SPEED_SUPER) {
1101 			mutex_unlock(&usb_bus_idr_lock);
1102 			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1103 					dev_name(&usb_dev->dev), retval);
1104 			return retval;
1105 		}
1106 	}
1107 
1108 	retval = usb_new_device (usb_dev);
1109 	if (retval) {
1110 		dev_err (parent_dev, "can't register root hub for %s, %d\n",
1111 				dev_name(&usb_dev->dev), retval);
1112 	} else {
1113 		spin_lock_irq (&hcd_root_hub_lock);
1114 		hcd->rh_registered = 1;
1115 		spin_unlock_irq (&hcd_root_hub_lock);
1116 
1117 		/* Did the HC die before the root hub was registered? */
1118 		if (HCD_DEAD(hcd))
1119 			usb_hc_died (hcd);	/* This time clean up */
1120 	}
1121 	mutex_unlock(&usb_bus_idr_lock);
1122 
1123 	return retval;
1124 }
1125 
1126 /*
1127  * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1128  * @bus: the bus which the root hub belongs to
1129  * @portnum: the port which is being resumed
1130  *
1131  * HCDs should call this function when they know that a resume signal is
1132  * being sent to a root-hub port.  The root hub will be prevented from
1133  * going into autosuspend until usb_hcd_end_port_resume() is called.
1134  *
1135  * The bus's private lock must be held by the caller.
1136  */
1137 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1138 {
1139 	unsigned bit = 1 << portnum;
1140 
1141 	if (!(bus->resuming_ports & bit)) {
1142 		bus->resuming_ports |= bit;
1143 		pm_runtime_get_noresume(&bus->root_hub->dev);
1144 	}
1145 }
1146 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1147 
1148 /*
1149  * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1150  * @bus: the bus which the root hub belongs to
1151  * @portnum: the port which is being resumed
1152  *
1153  * HCDs should call this function when they know that a resume signal has
1154  * stopped being sent to a root-hub port.  The root hub will be allowed to
1155  * autosuspend again.
1156  *
1157  * The bus's private lock must be held by the caller.
1158  */
1159 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1160 {
1161 	unsigned bit = 1 << portnum;
1162 
1163 	if (bus->resuming_ports & bit) {
1164 		bus->resuming_ports &= ~bit;
1165 		pm_runtime_put_noidle(&bus->root_hub->dev);
1166 	}
1167 }
1168 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1169 
1170 /*-------------------------------------------------------------------------*/
1171 
1172 /**
1173  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1174  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1175  * @is_input: true iff the transaction sends data to the host
1176  * @isoc: true for isochronous transactions, false for interrupt ones
1177  * @bytecount: how many bytes in the transaction.
1178  *
1179  * Return: Approximate bus time in nanoseconds for a periodic transaction.
1180  *
1181  * Note:
1182  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1183  * scheduled in software, this function is only used for such scheduling.
1184  */
1185 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1186 {
1187 	unsigned long	tmp;
1188 
1189 	switch (speed) {
1190 	case USB_SPEED_LOW: 	/* INTR only */
1191 		if (is_input) {
1192 			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1193 			return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1194 		} else {
1195 			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1196 			return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1197 		}
1198 	case USB_SPEED_FULL:	/* ISOC or INTR */
1199 		if (isoc) {
1200 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1201 			return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1202 		} else {
1203 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1204 			return 9107L + BW_HOST_DELAY + tmp;
1205 		}
1206 	case USB_SPEED_HIGH:	/* ISOC or INTR */
1207 		/* FIXME adjust for input vs output */
1208 		if (isoc)
1209 			tmp = HS_NSECS_ISO (bytecount);
1210 		else
1211 			tmp = HS_NSECS (bytecount);
1212 		return tmp;
1213 	default:
1214 		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1215 		return -1;
1216 	}
1217 }
1218 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1219 
1220 
1221 /*-------------------------------------------------------------------------*/
1222 
1223 /*
1224  * Generic HC operations.
1225  */
1226 
1227 /*-------------------------------------------------------------------------*/
1228 
1229 /**
1230  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1231  * @hcd: host controller to which @urb was submitted
1232  * @urb: URB being submitted
1233  *
1234  * Host controller drivers should call this routine in their enqueue()
1235  * method.  The HCD's private spinlock must be held and interrupts must
1236  * be disabled.  The actions carried out here are required for URB
1237  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1238  *
1239  * Return: 0 for no error, otherwise a negative error code (in which case
1240  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1241  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1242  * the private spinlock and returning.
1243  */
1244 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1245 {
1246 	int		rc = 0;
1247 
1248 	spin_lock(&hcd_urb_list_lock);
1249 
1250 	/* Check that the URB isn't being killed */
1251 	if (unlikely(atomic_read(&urb->reject))) {
1252 		rc = -EPERM;
1253 		goto done;
1254 	}
1255 
1256 	if (unlikely(!urb->ep->enabled)) {
1257 		rc = -ENOENT;
1258 		goto done;
1259 	}
1260 
1261 	if (unlikely(!urb->dev->can_submit)) {
1262 		rc = -EHOSTUNREACH;
1263 		goto done;
1264 	}
1265 
1266 	/*
1267 	 * Check the host controller's state and add the URB to the
1268 	 * endpoint's queue.
1269 	 */
1270 	if (HCD_RH_RUNNING(hcd)) {
1271 		urb->unlinked = 0;
1272 		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1273 	} else {
1274 		rc = -ESHUTDOWN;
1275 		goto done;
1276 	}
1277  done:
1278 	spin_unlock(&hcd_urb_list_lock);
1279 	return rc;
1280 }
1281 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1282 
1283 /**
1284  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1285  * @hcd: host controller to which @urb was submitted
1286  * @urb: URB being checked for unlinkability
1287  * @status: error code to store in @urb if the unlink succeeds
1288  *
1289  * Host controller drivers should call this routine in their dequeue()
1290  * method.  The HCD's private spinlock must be held and interrupts must
1291  * be disabled.  The actions carried out here are required for making
1292  * sure than an unlink is valid.
1293  *
1294  * Return: 0 for no error, otherwise a negative error code (in which case
1295  * the dequeue() method must fail).  The possible error codes are:
1296  *
1297  *	-EIDRM: @urb was not submitted or has already completed.
1298  *		The completion function may not have been called yet.
1299  *
1300  *	-EBUSY: @urb has already been unlinked.
1301  */
1302 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1303 		int status)
1304 {
1305 	struct list_head	*tmp;
1306 
1307 	/* insist the urb is still queued */
1308 	list_for_each(tmp, &urb->ep->urb_list) {
1309 		if (tmp == &urb->urb_list)
1310 			break;
1311 	}
1312 	if (tmp != &urb->urb_list)
1313 		return -EIDRM;
1314 
1315 	/* Any status except -EINPROGRESS means something already started to
1316 	 * unlink this URB from the hardware.  So there's no more work to do.
1317 	 */
1318 	if (urb->unlinked)
1319 		return -EBUSY;
1320 	urb->unlinked = status;
1321 	return 0;
1322 }
1323 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1324 
1325 /**
1326  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1327  * @hcd: host controller to which @urb was submitted
1328  * @urb: URB being unlinked
1329  *
1330  * Host controller drivers should call this routine before calling
1331  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1332  * interrupts must be disabled.  The actions carried out here are required
1333  * for URB completion.
1334  */
1335 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1336 {
1337 	/* clear all state linking urb to this dev (and hcd) */
1338 	spin_lock(&hcd_urb_list_lock);
1339 	list_del_init(&urb->urb_list);
1340 	spin_unlock(&hcd_urb_list_lock);
1341 }
1342 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1343 
1344 /*
1345  * Some usb host controllers can only perform dma using a small SRAM area.
1346  * The usb core itself is however optimized for host controllers that can dma
1347  * using regular system memory - like pci devices doing bus mastering.
1348  *
1349  * To support host controllers with limited dma capabilities we provide dma
1350  * bounce buffers. This feature can be enabled by initializing
1351  * hcd->localmem_pool using usb_hcd_setup_local_mem().
1352  * For this to work properly the host controller code must first use the
1353  * function dma_declare_coherent_memory() to point out which memory area
1354  * that should be used for dma allocations.
1355  *
1356  * The initialized hcd->localmem_pool then tells the usb code to allocate all
1357  * data for dma using the genalloc API.
1358  *
1359  * So, to summarize...
1360  *
1361  * - We need "local" memory, canonical example being
1362  *   a small SRAM on a discrete controller being the
1363  *   only memory that the controller can read ...
1364  *   (a) "normal" kernel memory is no good, and
1365  *   (b) there's not enough to share
1366  *
1367  * - So we use that, even though the primary requirement
1368  *   is that the memory be "local" (hence addressable
1369  *   by that device), not "coherent".
1370  *
1371  */
1372 
1373 static int hcd_alloc_coherent(struct usb_bus *bus,
1374 			      gfp_t mem_flags, dma_addr_t *dma_handle,
1375 			      void **vaddr_handle, size_t size,
1376 			      enum dma_data_direction dir)
1377 {
1378 	unsigned char *vaddr;
1379 
1380 	if (*vaddr_handle == NULL) {
1381 		WARN_ON_ONCE(1);
1382 		return -EFAULT;
1383 	}
1384 
1385 	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1386 				 mem_flags, dma_handle);
1387 	if (!vaddr)
1388 		return -ENOMEM;
1389 
1390 	/*
1391 	 * Store the virtual address of the buffer at the end
1392 	 * of the allocated dma buffer. The size of the buffer
1393 	 * may be uneven so use unaligned functions instead
1394 	 * of just rounding up. It makes sense to optimize for
1395 	 * memory footprint over access speed since the amount
1396 	 * of memory available for dma may be limited.
1397 	 */
1398 	put_unaligned((unsigned long)*vaddr_handle,
1399 		      (unsigned long *)(vaddr + size));
1400 
1401 	if (dir == DMA_TO_DEVICE)
1402 		memcpy(vaddr, *vaddr_handle, size);
1403 
1404 	*vaddr_handle = vaddr;
1405 	return 0;
1406 }
1407 
1408 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1409 			      void **vaddr_handle, size_t size,
1410 			      enum dma_data_direction dir)
1411 {
1412 	unsigned char *vaddr = *vaddr_handle;
1413 
1414 	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1415 
1416 	if (dir == DMA_FROM_DEVICE)
1417 		memcpy(vaddr, *vaddr_handle, size);
1418 
1419 	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1420 
1421 	*vaddr_handle = vaddr;
1422 	*dma_handle = 0;
1423 }
1424 
1425 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1426 {
1427 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1428 	    (urb->transfer_flags & URB_SETUP_MAP_SINGLE))
1429 		dma_unmap_single(hcd->self.sysdev,
1430 				urb->setup_dma,
1431 				sizeof(struct usb_ctrlrequest),
1432 				DMA_TO_DEVICE);
1433 	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1434 		hcd_free_coherent(urb->dev->bus,
1435 				&urb->setup_dma,
1436 				(void **) &urb->setup_packet,
1437 				sizeof(struct usb_ctrlrequest),
1438 				DMA_TO_DEVICE);
1439 
1440 	/* Make it safe to call this routine more than once */
1441 	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1442 }
1443 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1444 
1445 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1446 {
1447 	if (hcd->driver->unmap_urb_for_dma)
1448 		hcd->driver->unmap_urb_for_dma(hcd, urb);
1449 	else
1450 		usb_hcd_unmap_urb_for_dma(hcd, urb);
1451 }
1452 
1453 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1454 {
1455 	enum dma_data_direction dir;
1456 
1457 	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1458 
1459 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1460 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1461 	    (urb->transfer_flags & URB_DMA_MAP_SG))
1462 		dma_unmap_sg(hcd->self.sysdev,
1463 				urb->sg,
1464 				urb->num_sgs,
1465 				dir);
1466 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1467 		 (urb->transfer_flags & URB_DMA_MAP_PAGE))
1468 		dma_unmap_page(hcd->self.sysdev,
1469 				urb->transfer_dma,
1470 				urb->transfer_buffer_length,
1471 				dir);
1472 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1473 		 (urb->transfer_flags & URB_DMA_MAP_SINGLE))
1474 		dma_unmap_single(hcd->self.sysdev,
1475 				urb->transfer_dma,
1476 				urb->transfer_buffer_length,
1477 				dir);
1478 	else if (urb->transfer_flags & URB_MAP_LOCAL)
1479 		hcd_free_coherent(urb->dev->bus,
1480 				&urb->transfer_dma,
1481 				&urb->transfer_buffer,
1482 				urb->transfer_buffer_length,
1483 				dir);
1484 
1485 	/* Make it safe to call this routine more than once */
1486 	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1487 			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1488 }
1489 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1490 
1491 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1492 			   gfp_t mem_flags)
1493 {
1494 	if (hcd->driver->map_urb_for_dma)
1495 		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1496 	else
1497 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1498 }
1499 
1500 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1501 			    gfp_t mem_flags)
1502 {
1503 	enum dma_data_direction dir;
1504 	int ret = 0;
1505 
1506 	/* Map the URB's buffers for DMA access.
1507 	 * Lower level HCD code should use *_dma exclusively,
1508 	 * unless it uses pio or talks to another transport,
1509 	 * or uses the provided scatter gather list for bulk.
1510 	 */
1511 
1512 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1513 		if (hcd->self.uses_pio_for_control)
1514 			return ret;
1515 		if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) {
1516 			if (is_vmalloc_addr(urb->setup_packet)) {
1517 				WARN_ONCE(1, "setup packet is not dma capable\n");
1518 				return -EAGAIN;
1519 			} else if (object_is_on_stack(urb->setup_packet)) {
1520 				WARN_ONCE(1, "setup packet is on stack\n");
1521 				return -EAGAIN;
1522 			}
1523 
1524 			urb->setup_dma = dma_map_single(
1525 					hcd->self.sysdev,
1526 					urb->setup_packet,
1527 					sizeof(struct usb_ctrlrequest),
1528 					DMA_TO_DEVICE);
1529 			if (dma_mapping_error(hcd->self.sysdev,
1530 						urb->setup_dma))
1531 				return -EAGAIN;
1532 			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1533 		} else if (hcd->localmem_pool) {
1534 			ret = hcd_alloc_coherent(
1535 					urb->dev->bus, mem_flags,
1536 					&urb->setup_dma,
1537 					(void **)&urb->setup_packet,
1538 					sizeof(struct usb_ctrlrequest),
1539 					DMA_TO_DEVICE);
1540 			if (ret)
1541 				return ret;
1542 			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1543 		}
1544 	}
1545 
1546 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1547 	if (urb->transfer_buffer_length != 0
1548 	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1549 		if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) {
1550 			if (urb->num_sgs) {
1551 				int n;
1552 
1553 				/* We don't support sg for isoc transfers ! */
1554 				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1555 					WARN_ON(1);
1556 					return -EINVAL;
1557 				}
1558 
1559 				n = dma_map_sg(
1560 						hcd->self.sysdev,
1561 						urb->sg,
1562 						urb->num_sgs,
1563 						dir);
1564 				if (n <= 0)
1565 					ret = -EAGAIN;
1566 				else
1567 					urb->transfer_flags |= URB_DMA_MAP_SG;
1568 				urb->num_mapped_sgs = n;
1569 				if (n != urb->num_sgs)
1570 					urb->transfer_flags |=
1571 							URB_DMA_SG_COMBINED;
1572 			} else if (urb->sg) {
1573 				struct scatterlist *sg = urb->sg;
1574 				urb->transfer_dma = dma_map_page(
1575 						hcd->self.sysdev,
1576 						sg_page(sg),
1577 						sg->offset,
1578 						urb->transfer_buffer_length,
1579 						dir);
1580 				if (dma_mapping_error(hcd->self.sysdev,
1581 						urb->transfer_dma))
1582 					ret = -EAGAIN;
1583 				else
1584 					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1585 			} else if (is_vmalloc_addr(urb->transfer_buffer)) {
1586 				WARN_ONCE(1, "transfer buffer not dma capable\n");
1587 				ret = -EAGAIN;
1588 			} else if (object_is_on_stack(urb->transfer_buffer)) {
1589 				WARN_ONCE(1, "transfer buffer is on stack\n");
1590 				ret = -EAGAIN;
1591 			} else {
1592 				urb->transfer_dma = dma_map_single(
1593 						hcd->self.sysdev,
1594 						urb->transfer_buffer,
1595 						urb->transfer_buffer_length,
1596 						dir);
1597 				if (dma_mapping_error(hcd->self.sysdev,
1598 						urb->transfer_dma))
1599 					ret = -EAGAIN;
1600 				else
1601 					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1602 			}
1603 		} else if (hcd->localmem_pool) {
1604 			ret = hcd_alloc_coherent(
1605 					urb->dev->bus, mem_flags,
1606 					&urb->transfer_dma,
1607 					&urb->transfer_buffer,
1608 					urb->transfer_buffer_length,
1609 					dir);
1610 			if (ret == 0)
1611 				urb->transfer_flags |= URB_MAP_LOCAL;
1612 		}
1613 		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1614 				URB_SETUP_MAP_LOCAL)))
1615 			usb_hcd_unmap_urb_for_dma(hcd, urb);
1616 	}
1617 	return ret;
1618 }
1619 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1620 
1621 /*-------------------------------------------------------------------------*/
1622 
1623 /* may be called in any context with a valid urb->dev usecount
1624  * caller surrenders "ownership" of urb
1625  * expects usb_submit_urb() to have sanity checked and conditioned all
1626  * inputs in the urb
1627  */
1628 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1629 {
1630 	int			status;
1631 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1632 
1633 	/* increment urb's reference count as part of giving it to the HCD
1634 	 * (which will control it).  HCD guarantees that it either returns
1635 	 * an error or calls giveback(), but not both.
1636 	 */
1637 	usb_get_urb(urb);
1638 	atomic_inc(&urb->use_count);
1639 	atomic_inc(&urb->dev->urbnum);
1640 	usbmon_urb_submit(&hcd->self, urb);
1641 
1642 	/* NOTE requirements on root-hub callers (usbfs and the hub
1643 	 * driver, for now):  URBs' urb->transfer_buffer must be
1644 	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1645 	 * they could clobber root hub response data.  Also, control
1646 	 * URBs must be submitted in process context with interrupts
1647 	 * enabled.
1648 	 */
1649 
1650 	if (is_root_hub(urb->dev)) {
1651 		status = rh_urb_enqueue(hcd, urb);
1652 	} else {
1653 		status = map_urb_for_dma(hcd, urb, mem_flags);
1654 		if (likely(status == 0)) {
1655 			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1656 			if (unlikely(status))
1657 				unmap_urb_for_dma(hcd, urb);
1658 		}
1659 	}
1660 
1661 	if (unlikely(status)) {
1662 		usbmon_urb_submit_error(&hcd->self, urb, status);
1663 		urb->hcpriv = NULL;
1664 		INIT_LIST_HEAD(&urb->urb_list);
1665 		atomic_dec(&urb->use_count);
1666 		atomic_dec(&urb->dev->urbnum);
1667 		if (atomic_read(&urb->reject))
1668 			wake_up(&usb_kill_urb_queue);
1669 		usb_put_urb(urb);
1670 	}
1671 	return status;
1672 }
1673 
1674 /*-------------------------------------------------------------------------*/
1675 
1676 /* this makes the hcd giveback() the urb more quickly, by kicking it
1677  * off hardware queues (which may take a while) and returning it as
1678  * soon as practical.  we've already set up the urb's return status,
1679  * but we can't know if the callback completed already.
1680  */
1681 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1682 {
1683 	int		value;
1684 
1685 	if (is_root_hub(urb->dev))
1686 		value = usb_rh_urb_dequeue(hcd, urb, status);
1687 	else {
1688 
1689 		/* The only reason an HCD might fail this call is if
1690 		 * it has not yet fully queued the urb to begin with.
1691 		 * Such failures should be harmless. */
1692 		value = hcd->driver->urb_dequeue(hcd, urb, status);
1693 	}
1694 	return value;
1695 }
1696 
1697 /*
1698  * called in any context
1699  *
1700  * caller guarantees urb won't be recycled till both unlink()
1701  * and the urb's completion function return
1702  */
1703 int usb_hcd_unlink_urb (struct urb *urb, int status)
1704 {
1705 	struct usb_hcd		*hcd;
1706 	struct usb_device	*udev = urb->dev;
1707 	int			retval = -EIDRM;
1708 	unsigned long		flags;
1709 
1710 	/* Prevent the device and bus from going away while
1711 	 * the unlink is carried out.  If they are already gone
1712 	 * then urb->use_count must be 0, since disconnected
1713 	 * devices can't have any active URBs.
1714 	 */
1715 	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1716 	if (atomic_read(&urb->use_count) > 0) {
1717 		retval = 0;
1718 		usb_get_dev(udev);
1719 	}
1720 	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1721 	if (retval == 0) {
1722 		hcd = bus_to_hcd(urb->dev->bus);
1723 		retval = unlink1(hcd, urb, status);
1724 		if (retval == 0)
1725 			retval = -EINPROGRESS;
1726 		else if (retval != -EIDRM && retval != -EBUSY)
1727 			dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n",
1728 					urb, retval);
1729 		usb_put_dev(udev);
1730 	}
1731 	return retval;
1732 }
1733 
1734 /*-------------------------------------------------------------------------*/
1735 
1736 static void __usb_hcd_giveback_urb(struct urb *urb)
1737 {
1738 	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1739 	struct usb_anchor *anchor = urb->anchor;
1740 	int status = urb->unlinked;
1741 
1742 	urb->hcpriv = NULL;
1743 	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1744 	    urb->actual_length < urb->transfer_buffer_length &&
1745 	    !status))
1746 		status = -EREMOTEIO;
1747 
1748 	unmap_urb_for_dma(hcd, urb);
1749 	usbmon_urb_complete(&hcd->self, urb, status);
1750 	usb_anchor_suspend_wakeups(anchor);
1751 	usb_unanchor_urb(urb);
1752 	if (likely(status == 0))
1753 		usb_led_activity(USB_LED_EVENT_HOST);
1754 
1755 	/* pass ownership to the completion handler */
1756 	urb->status = status;
1757 	urb->complete(urb);
1758 
1759 	usb_anchor_resume_wakeups(anchor);
1760 	atomic_dec(&urb->use_count);
1761 	if (unlikely(atomic_read(&urb->reject)))
1762 		wake_up(&usb_kill_urb_queue);
1763 	usb_put_urb(urb);
1764 }
1765 
1766 static void usb_giveback_urb_bh(unsigned long param)
1767 {
1768 	struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param;
1769 	struct list_head local_list;
1770 
1771 	spin_lock_irq(&bh->lock);
1772 	bh->running = true;
1773  restart:
1774 	list_replace_init(&bh->head, &local_list);
1775 	spin_unlock_irq(&bh->lock);
1776 
1777 	while (!list_empty(&local_list)) {
1778 		struct urb *urb;
1779 
1780 		urb = list_entry(local_list.next, struct urb, urb_list);
1781 		list_del_init(&urb->urb_list);
1782 		bh->completing_ep = urb->ep;
1783 		__usb_hcd_giveback_urb(urb);
1784 		bh->completing_ep = NULL;
1785 	}
1786 
1787 	/* check if there are new URBs to giveback */
1788 	spin_lock_irq(&bh->lock);
1789 	if (!list_empty(&bh->head))
1790 		goto restart;
1791 	bh->running = false;
1792 	spin_unlock_irq(&bh->lock);
1793 }
1794 
1795 /**
1796  * usb_hcd_giveback_urb - return URB from HCD to device driver
1797  * @hcd: host controller returning the URB
1798  * @urb: urb being returned to the USB device driver.
1799  * @status: completion status code for the URB.
1800  * Context: in_interrupt()
1801  *
1802  * This hands the URB from HCD to its USB device driver, using its
1803  * completion function.  The HCD has freed all per-urb resources
1804  * (and is done using urb->hcpriv).  It also released all HCD locks;
1805  * the device driver won't cause problems if it frees, modifies,
1806  * or resubmits this URB.
1807  *
1808  * If @urb was unlinked, the value of @status will be overridden by
1809  * @urb->unlinked.  Erroneous short transfers are detected in case
1810  * the HCD hasn't checked for them.
1811  */
1812 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1813 {
1814 	struct giveback_urb_bh *bh;
1815 	bool running, high_prio_bh;
1816 
1817 	/* pass status to tasklet via unlinked */
1818 	if (likely(!urb->unlinked))
1819 		urb->unlinked = status;
1820 
1821 	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1822 		__usb_hcd_giveback_urb(urb);
1823 		return;
1824 	}
1825 
1826 	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
1827 		bh = &hcd->high_prio_bh;
1828 		high_prio_bh = true;
1829 	} else {
1830 		bh = &hcd->low_prio_bh;
1831 		high_prio_bh = false;
1832 	}
1833 
1834 	spin_lock(&bh->lock);
1835 	list_add_tail(&urb->urb_list, &bh->head);
1836 	running = bh->running;
1837 	spin_unlock(&bh->lock);
1838 
1839 	if (running)
1840 		;
1841 	else if (high_prio_bh)
1842 		tasklet_hi_schedule(&bh->bh);
1843 	else
1844 		tasklet_schedule(&bh->bh);
1845 }
1846 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1847 
1848 /*-------------------------------------------------------------------------*/
1849 
1850 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1851  * queue to drain completely.  The caller must first insure that no more
1852  * URBs can be submitted for this endpoint.
1853  */
1854 void usb_hcd_flush_endpoint(struct usb_device *udev,
1855 		struct usb_host_endpoint *ep)
1856 {
1857 	struct usb_hcd		*hcd;
1858 	struct urb		*urb;
1859 
1860 	if (!ep)
1861 		return;
1862 	might_sleep();
1863 	hcd = bus_to_hcd(udev->bus);
1864 
1865 	/* No more submits can occur */
1866 	spin_lock_irq(&hcd_urb_list_lock);
1867 rescan:
1868 	list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) {
1869 		int	is_in;
1870 
1871 		if (urb->unlinked)
1872 			continue;
1873 		usb_get_urb (urb);
1874 		is_in = usb_urb_dir_in(urb);
1875 		spin_unlock(&hcd_urb_list_lock);
1876 
1877 		/* kick hcd */
1878 		unlink1(hcd, urb, -ESHUTDOWN);
1879 		dev_dbg (hcd->self.controller,
1880 			"shutdown urb %pK ep%d%s-%s\n",
1881 			urb, usb_endpoint_num(&ep->desc),
1882 			is_in ? "in" : "out",
1883 			usb_ep_type_string(usb_endpoint_type(&ep->desc)));
1884 		usb_put_urb (urb);
1885 
1886 		/* list contents may have changed */
1887 		spin_lock(&hcd_urb_list_lock);
1888 		goto rescan;
1889 	}
1890 	spin_unlock_irq(&hcd_urb_list_lock);
1891 
1892 	/* Wait until the endpoint queue is completely empty */
1893 	while (!list_empty (&ep->urb_list)) {
1894 		spin_lock_irq(&hcd_urb_list_lock);
1895 
1896 		/* The list may have changed while we acquired the spinlock */
1897 		urb = NULL;
1898 		if (!list_empty (&ep->urb_list)) {
1899 			urb = list_entry (ep->urb_list.prev, struct urb,
1900 					urb_list);
1901 			usb_get_urb (urb);
1902 		}
1903 		spin_unlock_irq(&hcd_urb_list_lock);
1904 
1905 		if (urb) {
1906 			usb_kill_urb (urb);
1907 			usb_put_urb (urb);
1908 		}
1909 	}
1910 }
1911 
1912 /**
1913  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1914  *				the bus bandwidth
1915  * @udev: target &usb_device
1916  * @new_config: new configuration to install
1917  * @cur_alt: the current alternate interface setting
1918  * @new_alt: alternate interface setting that is being installed
1919  *
1920  * To change configurations, pass in the new configuration in new_config,
1921  * and pass NULL for cur_alt and new_alt.
1922  *
1923  * To reset a device's configuration (put the device in the ADDRESSED state),
1924  * pass in NULL for new_config, cur_alt, and new_alt.
1925  *
1926  * To change alternate interface settings, pass in NULL for new_config,
1927  * pass in the current alternate interface setting in cur_alt,
1928  * and pass in the new alternate interface setting in new_alt.
1929  *
1930  * Return: An error if the requested bandwidth change exceeds the
1931  * bus bandwidth or host controller internal resources.
1932  */
1933 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1934 		struct usb_host_config *new_config,
1935 		struct usb_host_interface *cur_alt,
1936 		struct usb_host_interface *new_alt)
1937 {
1938 	int num_intfs, i, j;
1939 	struct usb_host_interface *alt = NULL;
1940 	int ret = 0;
1941 	struct usb_hcd *hcd;
1942 	struct usb_host_endpoint *ep;
1943 
1944 	hcd = bus_to_hcd(udev->bus);
1945 	if (!hcd->driver->check_bandwidth)
1946 		return 0;
1947 
1948 	/* Configuration is being removed - set configuration 0 */
1949 	if (!new_config && !cur_alt) {
1950 		for (i = 1; i < 16; ++i) {
1951 			ep = udev->ep_out[i];
1952 			if (ep)
1953 				hcd->driver->drop_endpoint(hcd, udev, ep);
1954 			ep = udev->ep_in[i];
1955 			if (ep)
1956 				hcd->driver->drop_endpoint(hcd, udev, ep);
1957 		}
1958 		hcd->driver->check_bandwidth(hcd, udev);
1959 		return 0;
1960 	}
1961 	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1962 	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1963 	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1964 	 * ok to exclude it.
1965 	 */
1966 	if (new_config) {
1967 		num_intfs = new_config->desc.bNumInterfaces;
1968 		/* Remove endpoints (except endpoint 0, which is always on the
1969 		 * schedule) from the old config from the schedule
1970 		 */
1971 		for (i = 1; i < 16; ++i) {
1972 			ep = udev->ep_out[i];
1973 			if (ep) {
1974 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1975 				if (ret < 0)
1976 					goto reset;
1977 			}
1978 			ep = udev->ep_in[i];
1979 			if (ep) {
1980 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1981 				if (ret < 0)
1982 					goto reset;
1983 			}
1984 		}
1985 		for (i = 0; i < num_intfs; ++i) {
1986 			struct usb_host_interface *first_alt;
1987 			int iface_num;
1988 
1989 			first_alt = &new_config->intf_cache[i]->altsetting[0];
1990 			iface_num = first_alt->desc.bInterfaceNumber;
1991 			/* Set up endpoints for alternate interface setting 0 */
1992 			alt = usb_find_alt_setting(new_config, iface_num, 0);
1993 			if (!alt)
1994 				/* No alt setting 0? Pick the first setting. */
1995 				alt = first_alt;
1996 
1997 			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1998 				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1999 				if (ret < 0)
2000 					goto reset;
2001 			}
2002 		}
2003 	}
2004 	if (cur_alt && new_alt) {
2005 		struct usb_interface *iface = usb_ifnum_to_if(udev,
2006 				cur_alt->desc.bInterfaceNumber);
2007 
2008 		if (!iface)
2009 			return -EINVAL;
2010 		if (iface->resetting_device) {
2011 			/*
2012 			 * The USB core just reset the device, so the xHCI host
2013 			 * and the device will think alt setting 0 is installed.
2014 			 * However, the USB core will pass in the alternate
2015 			 * setting installed before the reset as cur_alt.  Dig
2016 			 * out the alternate setting 0 structure, or the first
2017 			 * alternate setting if a broken device doesn't have alt
2018 			 * setting 0.
2019 			 */
2020 			cur_alt = usb_altnum_to_altsetting(iface, 0);
2021 			if (!cur_alt)
2022 				cur_alt = &iface->altsetting[0];
2023 		}
2024 
2025 		/* Drop all the endpoints in the current alt setting */
2026 		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
2027 			ret = hcd->driver->drop_endpoint(hcd, udev,
2028 					&cur_alt->endpoint[i]);
2029 			if (ret < 0)
2030 				goto reset;
2031 		}
2032 		/* Add all the endpoints in the new alt setting */
2033 		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
2034 			ret = hcd->driver->add_endpoint(hcd, udev,
2035 					&new_alt->endpoint[i]);
2036 			if (ret < 0)
2037 				goto reset;
2038 		}
2039 	}
2040 	ret = hcd->driver->check_bandwidth(hcd, udev);
2041 reset:
2042 	if (ret < 0)
2043 		hcd->driver->reset_bandwidth(hcd, udev);
2044 	return ret;
2045 }
2046 
2047 /* Disables the endpoint: synchronizes with the hcd to make sure all
2048  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
2049  * have been called previously.  Use for set_configuration, set_interface,
2050  * driver removal, physical disconnect.
2051  *
2052  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
2053  * type, maxpacket size, toggle, halt status, and scheduling.
2054  */
2055 void usb_hcd_disable_endpoint(struct usb_device *udev,
2056 		struct usb_host_endpoint *ep)
2057 {
2058 	struct usb_hcd		*hcd;
2059 
2060 	might_sleep();
2061 	hcd = bus_to_hcd(udev->bus);
2062 	if (hcd->driver->endpoint_disable)
2063 		hcd->driver->endpoint_disable(hcd, ep);
2064 }
2065 
2066 /**
2067  * usb_hcd_reset_endpoint - reset host endpoint state
2068  * @udev: USB device.
2069  * @ep:   the endpoint to reset.
2070  *
2071  * Resets any host endpoint state such as the toggle bit, sequence
2072  * number and current window.
2073  */
2074 void usb_hcd_reset_endpoint(struct usb_device *udev,
2075 			    struct usb_host_endpoint *ep)
2076 {
2077 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2078 
2079 	if (hcd->driver->endpoint_reset)
2080 		hcd->driver->endpoint_reset(hcd, ep);
2081 	else {
2082 		int epnum = usb_endpoint_num(&ep->desc);
2083 		int is_out = usb_endpoint_dir_out(&ep->desc);
2084 		int is_control = usb_endpoint_xfer_control(&ep->desc);
2085 
2086 		usb_settoggle(udev, epnum, is_out, 0);
2087 		if (is_control)
2088 			usb_settoggle(udev, epnum, !is_out, 0);
2089 	}
2090 }
2091 
2092 /**
2093  * usb_alloc_streams - allocate bulk endpoint stream IDs.
2094  * @interface:		alternate setting that includes all endpoints.
2095  * @eps:		array of endpoints that need streams.
2096  * @num_eps:		number of endpoints in the array.
2097  * @num_streams:	number of streams to allocate.
2098  * @mem_flags:		flags hcd should use to allocate memory.
2099  *
2100  * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
2101  * Drivers may queue multiple transfers to different stream IDs, which may
2102  * complete in a different order than they were queued.
2103  *
2104  * Return: On success, the number of allocated streams. On failure, a negative
2105  * error code.
2106  */
2107 int usb_alloc_streams(struct usb_interface *interface,
2108 		struct usb_host_endpoint **eps, unsigned int num_eps,
2109 		unsigned int num_streams, gfp_t mem_flags)
2110 {
2111 	struct usb_hcd *hcd;
2112 	struct usb_device *dev;
2113 	int i, ret;
2114 
2115 	dev = interface_to_usbdev(interface);
2116 	hcd = bus_to_hcd(dev->bus);
2117 	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2118 		return -EINVAL;
2119 	if (dev->speed < USB_SPEED_SUPER)
2120 		return -EINVAL;
2121 	if (dev->state < USB_STATE_CONFIGURED)
2122 		return -ENODEV;
2123 
2124 	for (i = 0; i < num_eps; i++) {
2125 		/* Streams only apply to bulk endpoints. */
2126 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2127 			return -EINVAL;
2128 		/* Re-alloc is not allowed */
2129 		if (eps[i]->streams)
2130 			return -EINVAL;
2131 	}
2132 
2133 	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2134 			num_streams, mem_flags);
2135 	if (ret < 0)
2136 		return ret;
2137 
2138 	for (i = 0; i < num_eps; i++)
2139 		eps[i]->streams = ret;
2140 
2141 	return ret;
2142 }
2143 EXPORT_SYMBOL_GPL(usb_alloc_streams);
2144 
2145 /**
2146  * usb_free_streams - free bulk endpoint stream IDs.
2147  * @interface:	alternate setting that includes all endpoints.
2148  * @eps:	array of endpoints to remove streams from.
2149  * @num_eps:	number of endpoints in the array.
2150  * @mem_flags:	flags hcd should use to allocate memory.
2151  *
2152  * Reverts a group of bulk endpoints back to not using stream IDs.
2153  * Can fail if we are given bad arguments, or HCD is broken.
2154  *
2155  * Return: 0 on success. On failure, a negative error code.
2156  */
2157 int usb_free_streams(struct usb_interface *interface,
2158 		struct usb_host_endpoint **eps, unsigned int num_eps,
2159 		gfp_t mem_flags)
2160 {
2161 	struct usb_hcd *hcd;
2162 	struct usb_device *dev;
2163 	int i, ret;
2164 
2165 	dev = interface_to_usbdev(interface);
2166 	hcd = bus_to_hcd(dev->bus);
2167 	if (dev->speed < USB_SPEED_SUPER)
2168 		return -EINVAL;
2169 
2170 	/* Double-free is not allowed */
2171 	for (i = 0; i < num_eps; i++)
2172 		if (!eps[i] || !eps[i]->streams)
2173 			return -EINVAL;
2174 
2175 	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2176 	if (ret < 0)
2177 		return ret;
2178 
2179 	for (i = 0; i < num_eps; i++)
2180 		eps[i]->streams = 0;
2181 
2182 	return ret;
2183 }
2184 EXPORT_SYMBOL_GPL(usb_free_streams);
2185 
2186 /* Protect against drivers that try to unlink URBs after the device
2187  * is gone, by waiting until all unlinks for @udev are finished.
2188  * Since we don't currently track URBs by device, simply wait until
2189  * nothing is running in the locked region of usb_hcd_unlink_urb().
2190  */
2191 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2192 {
2193 	spin_lock_irq(&hcd_urb_unlink_lock);
2194 	spin_unlock_irq(&hcd_urb_unlink_lock);
2195 }
2196 
2197 /*-------------------------------------------------------------------------*/
2198 
2199 /* called in any context */
2200 int usb_hcd_get_frame_number (struct usb_device *udev)
2201 {
2202 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
2203 
2204 	if (!HCD_RH_RUNNING(hcd))
2205 		return -ESHUTDOWN;
2206 	return hcd->driver->get_frame_number (hcd);
2207 }
2208 
2209 /*-------------------------------------------------------------------------*/
2210 
2211 #ifdef	CONFIG_PM
2212 
2213 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2214 {
2215 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2216 	int		status;
2217 	int		old_state = hcd->state;
2218 
2219 	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2220 			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2221 			rhdev->do_remote_wakeup);
2222 	if (HCD_DEAD(hcd)) {
2223 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2224 		return 0;
2225 	}
2226 
2227 	if (!hcd->driver->bus_suspend) {
2228 		status = -ENOENT;
2229 	} else {
2230 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2231 		hcd->state = HC_STATE_QUIESCING;
2232 		status = hcd->driver->bus_suspend(hcd);
2233 	}
2234 	if (status == 0) {
2235 		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2236 		hcd->state = HC_STATE_SUSPENDED;
2237 
2238 		if (!PMSG_IS_AUTO(msg))
2239 			usb_phy_roothub_suspend(hcd->self.sysdev,
2240 						hcd->phy_roothub);
2241 
2242 		/* Did we race with a root-hub wakeup event? */
2243 		if (rhdev->do_remote_wakeup) {
2244 			char	buffer[6];
2245 
2246 			status = hcd->driver->hub_status_data(hcd, buffer);
2247 			if (status != 0) {
2248 				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2249 				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2250 				status = -EBUSY;
2251 			}
2252 		}
2253 	} else {
2254 		spin_lock_irq(&hcd_root_hub_lock);
2255 		if (!HCD_DEAD(hcd)) {
2256 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2257 			hcd->state = old_state;
2258 		}
2259 		spin_unlock_irq(&hcd_root_hub_lock);
2260 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2261 				"suspend", status);
2262 	}
2263 	return status;
2264 }
2265 
2266 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2267 {
2268 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2269 	int		status;
2270 	int		old_state = hcd->state;
2271 
2272 	dev_dbg(&rhdev->dev, "usb %sresume\n",
2273 			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2274 	if (HCD_DEAD(hcd)) {
2275 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2276 		return 0;
2277 	}
2278 
2279 	if (!PMSG_IS_AUTO(msg)) {
2280 		status = usb_phy_roothub_resume(hcd->self.sysdev,
2281 						hcd->phy_roothub);
2282 		if (status)
2283 			return status;
2284 	}
2285 
2286 	if (!hcd->driver->bus_resume)
2287 		return -ENOENT;
2288 	if (HCD_RH_RUNNING(hcd))
2289 		return 0;
2290 
2291 	hcd->state = HC_STATE_RESUMING;
2292 	status = hcd->driver->bus_resume(hcd);
2293 	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2294 	if (status == 0) {
2295 		struct usb_device *udev;
2296 		int port1;
2297 
2298 		spin_lock_irq(&hcd_root_hub_lock);
2299 		if (!HCD_DEAD(hcd)) {
2300 			usb_set_device_state(rhdev, rhdev->actconfig
2301 					? USB_STATE_CONFIGURED
2302 					: USB_STATE_ADDRESS);
2303 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2304 			hcd->state = HC_STATE_RUNNING;
2305 		}
2306 		spin_unlock_irq(&hcd_root_hub_lock);
2307 
2308 		/*
2309 		 * Check whether any of the enabled ports on the root hub are
2310 		 * unsuspended.  If they are then a TRSMRCY delay is needed
2311 		 * (this is what the USB-2 spec calls a "global resume").
2312 		 * Otherwise we can skip the delay.
2313 		 */
2314 		usb_hub_for_each_child(rhdev, port1, udev) {
2315 			if (udev->state != USB_STATE_NOTATTACHED &&
2316 					!udev->port_is_suspended) {
2317 				usleep_range(10000, 11000);	/* TRSMRCY */
2318 				break;
2319 			}
2320 		}
2321 	} else {
2322 		hcd->state = old_state;
2323 		usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub);
2324 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2325 				"resume", status);
2326 		if (status != -ESHUTDOWN)
2327 			usb_hc_died(hcd);
2328 	}
2329 	return status;
2330 }
2331 
2332 /* Workqueue routine for root-hub remote wakeup */
2333 static void hcd_resume_work(struct work_struct *work)
2334 {
2335 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2336 	struct usb_device *udev = hcd->self.root_hub;
2337 
2338 	usb_remote_wakeup(udev);
2339 }
2340 
2341 /**
2342  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2343  * @hcd: host controller for this root hub
2344  *
2345  * The USB host controller calls this function when its root hub is
2346  * suspended (with the remote wakeup feature enabled) and a remote
2347  * wakeup request is received.  The routine submits a workqueue request
2348  * to resume the root hub (that is, manage its downstream ports again).
2349  */
2350 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2351 {
2352 	unsigned long flags;
2353 
2354 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2355 	if (hcd->rh_registered) {
2356 		pm_wakeup_event(&hcd->self.root_hub->dev, 0);
2357 		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2358 		queue_work(pm_wq, &hcd->wakeup_work);
2359 	}
2360 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2361 }
2362 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2363 
2364 #endif	/* CONFIG_PM */
2365 
2366 /*-------------------------------------------------------------------------*/
2367 
2368 #ifdef	CONFIG_USB_OTG
2369 
2370 /**
2371  * usb_bus_start_enum - start immediate enumeration (for OTG)
2372  * @bus: the bus (must use hcd framework)
2373  * @port_num: 1-based number of port; usually bus->otg_port
2374  * Context: in_interrupt()
2375  *
2376  * Starts enumeration, with an immediate reset followed later by
2377  * hub_wq identifying and possibly configuring the device.
2378  * This is needed by OTG controller drivers, where it helps meet
2379  * HNP protocol timing requirements for starting a port reset.
2380  *
2381  * Return: 0 if successful.
2382  */
2383 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2384 {
2385 	struct usb_hcd		*hcd;
2386 	int			status = -EOPNOTSUPP;
2387 
2388 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2389 	 * boards with root hubs hooked up to internal devices (instead of
2390 	 * just the OTG port) may need more attention to resetting...
2391 	 */
2392 	hcd = bus_to_hcd(bus);
2393 	if (port_num && hcd->driver->start_port_reset)
2394 		status = hcd->driver->start_port_reset(hcd, port_num);
2395 
2396 	/* allocate hub_wq shortly after (first) root port reset finishes;
2397 	 * it may issue others, until at least 50 msecs have passed.
2398 	 */
2399 	if (status == 0)
2400 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2401 	return status;
2402 }
2403 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2404 
2405 #endif
2406 
2407 /*-------------------------------------------------------------------------*/
2408 
2409 /**
2410  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2411  * @irq: the IRQ being raised
2412  * @__hcd: pointer to the HCD whose IRQ is being signaled
2413  *
2414  * If the controller isn't HALTed, calls the driver's irq handler.
2415  * Checks whether the controller is now dead.
2416  *
2417  * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2418  */
2419 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2420 {
2421 	struct usb_hcd		*hcd = __hcd;
2422 	irqreturn_t		rc;
2423 
2424 	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2425 		rc = IRQ_NONE;
2426 	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2427 		rc = IRQ_NONE;
2428 	else
2429 		rc = IRQ_HANDLED;
2430 
2431 	return rc;
2432 }
2433 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2434 
2435 /*-------------------------------------------------------------------------*/
2436 
2437 /* Workqueue routine for when the root-hub has died. */
2438 static void hcd_died_work(struct work_struct *work)
2439 {
2440 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, died_work);
2441 	static char *env[] = {
2442 		"ERROR=DEAD",
2443 		NULL
2444 	};
2445 
2446 	/* Notify user space that the host controller has died */
2447 	kobject_uevent_env(&hcd->self.root_hub->dev.kobj, KOBJ_OFFLINE, env);
2448 }
2449 
2450 /**
2451  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2452  * @hcd: pointer to the HCD representing the controller
2453  *
2454  * This is called by bus glue to report a USB host controller that died
2455  * while operations may still have been pending.  It's called automatically
2456  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2457  *
2458  * Only call this function with the primary HCD.
2459  */
2460 void usb_hc_died (struct usb_hcd *hcd)
2461 {
2462 	unsigned long flags;
2463 
2464 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2465 
2466 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2467 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2468 	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2469 	if (hcd->rh_registered) {
2470 		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2471 
2472 		/* make hub_wq clean up old urbs and devices */
2473 		usb_set_device_state (hcd->self.root_hub,
2474 				USB_STATE_NOTATTACHED);
2475 		usb_kick_hub_wq(hcd->self.root_hub);
2476 	}
2477 	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2478 		hcd = hcd->shared_hcd;
2479 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2480 		set_bit(HCD_FLAG_DEAD, &hcd->flags);
2481 		if (hcd->rh_registered) {
2482 			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2483 
2484 			/* make hub_wq clean up old urbs and devices */
2485 			usb_set_device_state(hcd->self.root_hub,
2486 					USB_STATE_NOTATTACHED);
2487 			usb_kick_hub_wq(hcd->self.root_hub);
2488 		}
2489 	}
2490 
2491 	/* Handle the case where this function gets called with a shared HCD */
2492 	if (usb_hcd_is_primary_hcd(hcd))
2493 		schedule_work(&hcd->died_work);
2494 	else
2495 		schedule_work(&hcd->primary_hcd->died_work);
2496 
2497 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2498 	/* Make sure that the other roothub is also deallocated. */
2499 }
2500 EXPORT_SYMBOL_GPL (usb_hc_died);
2501 
2502 /*-------------------------------------------------------------------------*/
2503 
2504 static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2505 {
2506 
2507 	spin_lock_init(&bh->lock);
2508 	INIT_LIST_HEAD(&bh->head);
2509 	tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh);
2510 }
2511 
2512 struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
2513 		struct device *sysdev, struct device *dev, const char *bus_name,
2514 		struct usb_hcd *primary_hcd)
2515 {
2516 	struct usb_hcd *hcd;
2517 
2518 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2519 	if (!hcd)
2520 		return NULL;
2521 	if (primary_hcd == NULL) {
2522 		hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex),
2523 				GFP_KERNEL);
2524 		if (!hcd->address0_mutex) {
2525 			kfree(hcd);
2526 			dev_dbg(dev, "hcd address0 mutex alloc failed\n");
2527 			return NULL;
2528 		}
2529 		mutex_init(hcd->address0_mutex);
2530 		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2531 				GFP_KERNEL);
2532 		if (!hcd->bandwidth_mutex) {
2533 			kfree(hcd->address0_mutex);
2534 			kfree(hcd);
2535 			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2536 			return NULL;
2537 		}
2538 		mutex_init(hcd->bandwidth_mutex);
2539 		dev_set_drvdata(dev, hcd);
2540 	} else {
2541 		mutex_lock(&usb_port_peer_mutex);
2542 		hcd->address0_mutex = primary_hcd->address0_mutex;
2543 		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2544 		hcd->primary_hcd = primary_hcd;
2545 		primary_hcd->primary_hcd = primary_hcd;
2546 		hcd->shared_hcd = primary_hcd;
2547 		primary_hcd->shared_hcd = hcd;
2548 		mutex_unlock(&usb_port_peer_mutex);
2549 	}
2550 
2551 	kref_init(&hcd->kref);
2552 
2553 	usb_bus_init(&hcd->self);
2554 	hcd->self.controller = dev;
2555 	hcd->self.sysdev = sysdev;
2556 	hcd->self.bus_name = bus_name;
2557 	hcd->self.uses_dma = (sysdev->dma_mask != NULL);
2558 
2559 	timer_setup(&hcd->rh_timer, rh_timer_func, 0);
2560 #ifdef CONFIG_PM
2561 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2562 #endif
2563 
2564 	INIT_WORK(&hcd->died_work, hcd_died_work);
2565 
2566 	hcd->driver = driver;
2567 	hcd->speed = driver->flags & HCD_MASK;
2568 	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2569 			"USB Host Controller";
2570 	return hcd;
2571 }
2572 EXPORT_SYMBOL_GPL(__usb_create_hcd);
2573 
2574 /**
2575  * usb_create_shared_hcd - create and initialize an HCD structure
2576  * @driver: HC driver that will use this hcd
2577  * @dev: device for this HC, stored in hcd->self.controller
2578  * @bus_name: value to store in hcd->self.bus_name
2579  * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2580  *              PCI device.  Only allocate certain resources for the primary HCD
2581  * Context: !in_interrupt()
2582  *
2583  * Allocate a struct usb_hcd, with extra space at the end for the
2584  * HC driver's private data.  Initialize the generic members of the
2585  * hcd structure.
2586  *
2587  * Return: On success, a pointer to the created and initialized HCD structure.
2588  * On failure (e.g. if memory is unavailable), %NULL.
2589  */
2590 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2591 		struct device *dev, const char *bus_name,
2592 		struct usb_hcd *primary_hcd)
2593 {
2594 	return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd);
2595 }
2596 EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2597 
2598 /**
2599  * usb_create_hcd - create and initialize an HCD structure
2600  * @driver: HC driver that will use this hcd
2601  * @dev: device for this HC, stored in hcd->self.controller
2602  * @bus_name: value to store in hcd->self.bus_name
2603  * Context: !in_interrupt()
2604  *
2605  * Allocate a struct usb_hcd, with extra space at the end for the
2606  * HC driver's private data.  Initialize the generic members of the
2607  * hcd structure.
2608  *
2609  * Return: On success, a pointer to the created and initialized HCD
2610  * structure. On failure (e.g. if memory is unavailable), %NULL.
2611  */
2612 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2613 		struct device *dev, const char *bus_name)
2614 {
2615 	return __usb_create_hcd(driver, dev, dev, bus_name, NULL);
2616 }
2617 EXPORT_SYMBOL_GPL(usb_create_hcd);
2618 
2619 /*
2620  * Roothubs that share one PCI device must also share the bandwidth mutex.
2621  * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2622  * deallocated.
2623  *
2624  * Make sure to deallocate the bandwidth_mutex only when the last HCD is
2625  * freed.  When hcd_release() is called for either hcd in a peer set,
2626  * invalidate the peer's ->shared_hcd and ->primary_hcd pointers.
2627  */
2628 static void hcd_release(struct kref *kref)
2629 {
2630 	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2631 
2632 	mutex_lock(&usb_port_peer_mutex);
2633 	if (hcd->shared_hcd) {
2634 		struct usb_hcd *peer = hcd->shared_hcd;
2635 
2636 		peer->shared_hcd = NULL;
2637 		peer->primary_hcd = NULL;
2638 	} else {
2639 		kfree(hcd->address0_mutex);
2640 		kfree(hcd->bandwidth_mutex);
2641 	}
2642 	mutex_unlock(&usb_port_peer_mutex);
2643 	kfree(hcd);
2644 }
2645 
2646 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2647 {
2648 	if (hcd)
2649 		kref_get (&hcd->kref);
2650 	return hcd;
2651 }
2652 EXPORT_SYMBOL_GPL(usb_get_hcd);
2653 
2654 void usb_put_hcd (struct usb_hcd *hcd)
2655 {
2656 	if (hcd)
2657 		kref_put (&hcd->kref, hcd_release);
2658 }
2659 EXPORT_SYMBOL_GPL(usb_put_hcd);
2660 
2661 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2662 {
2663 	if (!hcd->primary_hcd)
2664 		return 1;
2665 	return hcd == hcd->primary_hcd;
2666 }
2667 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2668 
2669 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2670 {
2671 	if (!hcd->driver->find_raw_port_number)
2672 		return port1;
2673 
2674 	return hcd->driver->find_raw_port_number(hcd, port1);
2675 }
2676 
2677 static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2678 		unsigned int irqnum, unsigned long irqflags)
2679 {
2680 	int retval;
2681 
2682 	if (hcd->driver->irq) {
2683 
2684 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2685 				hcd->driver->description, hcd->self.busnum);
2686 		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2687 				hcd->irq_descr, hcd);
2688 		if (retval != 0) {
2689 			dev_err(hcd->self.controller,
2690 					"request interrupt %d failed\n",
2691 					irqnum);
2692 			return retval;
2693 		}
2694 		hcd->irq = irqnum;
2695 		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2696 				(hcd->driver->flags & HCD_MEMORY) ?
2697 					"io mem" : "io base",
2698 					(unsigned long long)hcd->rsrc_start);
2699 	} else {
2700 		hcd->irq = 0;
2701 		if (hcd->rsrc_start)
2702 			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2703 					(hcd->driver->flags & HCD_MEMORY) ?
2704 					"io mem" : "io base",
2705 					(unsigned long long)hcd->rsrc_start);
2706 	}
2707 	return 0;
2708 }
2709 
2710 /*
2711  * Before we free this root hub, flush in-flight peering attempts
2712  * and disable peer lookups
2713  */
2714 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2715 {
2716 	struct usb_device *rhdev;
2717 
2718 	mutex_lock(&usb_port_peer_mutex);
2719 	rhdev = hcd->self.root_hub;
2720 	hcd->self.root_hub = NULL;
2721 	mutex_unlock(&usb_port_peer_mutex);
2722 	usb_put_dev(rhdev);
2723 }
2724 
2725 /**
2726  * usb_add_hcd - finish generic HCD structure initialization and register
2727  * @hcd: the usb_hcd structure to initialize
2728  * @irqnum: Interrupt line to allocate
2729  * @irqflags: Interrupt type flags
2730  *
2731  * Finish the remaining parts of generic HCD initialization: allocate the
2732  * buffers of consistent memory, register the bus, request the IRQ line,
2733  * and call the driver's reset() and start() routines.
2734  */
2735 int usb_add_hcd(struct usb_hcd *hcd,
2736 		unsigned int irqnum, unsigned long irqflags)
2737 {
2738 	int retval;
2739 	struct usb_device *rhdev;
2740 
2741 	if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) {
2742 		hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev);
2743 		if (IS_ERR(hcd->phy_roothub))
2744 			return PTR_ERR(hcd->phy_roothub);
2745 
2746 		retval = usb_phy_roothub_init(hcd->phy_roothub);
2747 		if (retval)
2748 			return retval;
2749 
2750 		retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2751 						  PHY_MODE_USB_HOST_SS);
2752 		if (retval)
2753 			retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2754 							  PHY_MODE_USB_HOST);
2755 		if (retval)
2756 			goto err_usb_phy_roothub_power_on;
2757 
2758 		retval = usb_phy_roothub_power_on(hcd->phy_roothub);
2759 		if (retval)
2760 			goto err_usb_phy_roothub_power_on;
2761 	}
2762 
2763 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2764 
2765 	switch (authorized_default) {
2766 	case USB_AUTHORIZE_NONE:
2767 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_NONE;
2768 		break;
2769 
2770 	case USB_AUTHORIZE_ALL:
2771 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_ALL;
2772 		break;
2773 
2774 	case USB_AUTHORIZE_INTERNAL:
2775 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_INTERNAL;
2776 		break;
2777 
2778 	case USB_AUTHORIZE_WIRED:
2779 	default:
2780 		hcd->dev_policy = hcd->wireless ?
2781 			USB_DEVICE_AUTHORIZE_NONE : USB_DEVICE_AUTHORIZE_ALL;
2782 		break;
2783 	}
2784 
2785 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2786 
2787 	/* per default all interfaces are authorized */
2788 	set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
2789 
2790 	/* HC is in reset state, but accessible.  Now do the one-time init,
2791 	 * bottom up so that hcds can customize the root hubs before hub_wq
2792 	 * starts talking to them.  (Note, bus id is assigned early too.)
2793 	 */
2794 	retval = hcd_buffer_create(hcd);
2795 	if (retval != 0) {
2796 		dev_dbg(hcd->self.sysdev, "pool alloc failed\n");
2797 		goto err_create_buf;
2798 	}
2799 
2800 	retval = usb_register_bus(&hcd->self);
2801 	if (retval < 0)
2802 		goto err_register_bus;
2803 
2804 	rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2805 	if (rhdev == NULL) {
2806 		dev_err(hcd->self.sysdev, "unable to allocate root hub\n");
2807 		retval = -ENOMEM;
2808 		goto err_allocate_root_hub;
2809 	}
2810 	mutex_lock(&usb_port_peer_mutex);
2811 	hcd->self.root_hub = rhdev;
2812 	mutex_unlock(&usb_port_peer_mutex);
2813 
2814 	rhdev->rx_lanes = 1;
2815 	rhdev->tx_lanes = 1;
2816 
2817 	switch (hcd->speed) {
2818 	case HCD_USB11:
2819 		rhdev->speed = USB_SPEED_FULL;
2820 		break;
2821 	case HCD_USB2:
2822 		rhdev->speed = USB_SPEED_HIGH;
2823 		break;
2824 	case HCD_USB25:
2825 		rhdev->speed = USB_SPEED_WIRELESS;
2826 		break;
2827 	case HCD_USB3:
2828 		rhdev->speed = USB_SPEED_SUPER;
2829 		break;
2830 	case HCD_USB32:
2831 		rhdev->rx_lanes = 2;
2832 		rhdev->tx_lanes = 2;
2833 		/* fall through */
2834 	case HCD_USB31:
2835 		rhdev->speed = USB_SPEED_SUPER_PLUS;
2836 		break;
2837 	default:
2838 		retval = -EINVAL;
2839 		goto err_set_rh_speed;
2840 	}
2841 
2842 	/* wakeup flag init defaults to "everything works" for root hubs,
2843 	 * but drivers can override it in reset() if needed, along with
2844 	 * recording the overall controller's system wakeup capability.
2845 	 */
2846 	device_set_wakeup_capable(&rhdev->dev, 1);
2847 
2848 	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2849 	 * registered.  But since the controller can die at any time,
2850 	 * let's initialize the flag before touching the hardware.
2851 	 */
2852 	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2853 
2854 	/* "reset" is misnamed; its role is now one-time init. the controller
2855 	 * should already have been reset (and boot firmware kicked off etc).
2856 	 */
2857 	if (hcd->driver->reset) {
2858 		retval = hcd->driver->reset(hcd);
2859 		if (retval < 0) {
2860 			dev_err(hcd->self.controller, "can't setup: %d\n",
2861 					retval);
2862 			goto err_hcd_driver_setup;
2863 		}
2864 	}
2865 	hcd->rh_pollable = 1;
2866 
2867 	/* NOTE: root hub and controller capabilities may not be the same */
2868 	if (device_can_wakeup(hcd->self.controller)
2869 			&& device_can_wakeup(&hcd->self.root_hub->dev))
2870 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2871 
2872 	/* initialize tasklets */
2873 	init_giveback_urb_bh(&hcd->high_prio_bh);
2874 	init_giveback_urb_bh(&hcd->low_prio_bh);
2875 
2876 	/* enable irqs just before we start the controller,
2877 	 * if the BIOS provides legacy PCI irqs.
2878 	 */
2879 	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2880 		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2881 		if (retval)
2882 			goto err_request_irq;
2883 	}
2884 
2885 	hcd->state = HC_STATE_RUNNING;
2886 	retval = hcd->driver->start(hcd);
2887 	if (retval < 0) {
2888 		dev_err(hcd->self.controller, "startup error %d\n", retval);
2889 		goto err_hcd_driver_start;
2890 	}
2891 
2892 	/* starting here, usbcore will pay attention to this root hub */
2893 	retval = register_root_hub(hcd);
2894 	if (retval != 0)
2895 		goto err_register_root_hub;
2896 
2897 	retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2898 	if (retval < 0) {
2899 		printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n",
2900 		       retval);
2901 		goto error_create_attr_group;
2902 	}
2903 	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2904 		usb_hcd_poll_rh_status(hcd);
2905 
2906 	return retval;
2907 
2908 error_create_attr_group:
2909 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2910 	if (HC_IS_RUNNING(hcd->state))
2911 		hcd->state = HC_STATE_QUIESCING;
2912 	spin_lock_irq(&hcd_root_hub_lock);
2913 	hcd->rh_registered = 0;
2914 	spin_unlock_irq(&hcd_root_hub_lock);
2915 
2916 #ifdef CONFIG_PM
2917 	cancel_work_sync(&hcd->wakeup_work);
2918 #endif
2919 	cancel_work_sync(&hcd->died_work);
2920 	mutex_lock(&usb_bus_idr_lock);
2921 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2922 	mutex_unlock(&usb_bus_idr_lock);
2923 err_register_root_hub:
2924 	hcd->rh_pollable = 0;
2925 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2926 	del_timer_sync(&hcd->rh_timer);
2927 	hcd->driver->stop(hcd);
2928 	hcd->state = HC_STATE_HALT;
2929 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2930 	del_timer_sync(&hcd->rh_timer);
2931 err_hcd_driver_start:
2932 	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2933 		free_irq(irqnum, hcd);
2934 err_request_irq:
2935 err_hcd_driver_setup:
2936 err_set_rh_speed:
2937 	usb_put_invalidate_rhdev(hcd);
2938 err_allocate_root_hub:
2939 	usb_deregister_bus(&hcd->self);
2940 err_register_bus:
2941 	hcd_buffer_destroy(hcd);
2942 err_create_buf:
2943 	usb_phy_roothub_power_off(hcd->phy_roothub);
2944 err_usb_phy_roothub_power_on:
2945 	usb_phy_roothub_exit(hcd->phy_roothub);
2946 
2947 	return retval;
2948 }
2949 EXPORT_SYMBOL_GPL(usb_add_hcd);
2950 
2951 /**
2952  * usb_remove_hcd - shutdown processing for generic HCDs
2953  * @hcd: the usb_hcd structure to remove
2954  * Context: !in_interrupt()
2955  *
2956  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2957  * invoking the HCD's stop() method.
2958  */
2959 void usb_remove_hcd(struct usb_hcd *hcd)
2960 {
2961 	struct usb_device *rhdev = hcd->self.root_hub;
2962 
2963 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2964 
2965 	usb_get_dev(rhdev);
2966 	sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2967 
2968 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2969 	if (HC_IS_RUNNING (hcd->state))
2970 		hcd->state = HC_STATE_QUIESCING;
2971 
2972 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2973 	spin_lock_irq (&hcd_root_hub_lock);
2974 	hcd->rh_registered = 0;
2975 	spin_unlock_irq (&hcd_root_hub_lock);
2976 
2977 #ifdef CONFIG_PM
2978 	cancel_work_sync(&hcd->wakeup_work);
2979 #endif
2980 	cancel_work_sync(&hcd->died_work);
2981 
2982 	mutex_lock(&usb_bus_idr_lock);
2983 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2984 	mutex_unlock(&usb_bus_idr_lock);
2985 
2986 	/*
2987 	 * tasklet_kill() isn't needed here because:
2988 	 * - driver's disconnect() called from usb_disconnect() should
2989 	 *   make sure its URBs are completed during the disconnect()
2990 	 *   callback
2991 	 *
2992 	 * - it is too late to run complete() here since driver may have
2993 	 *   been removed already now
2994 	 */
2995 
2996 	/* Prevent any more root-hub status calls from the timer.
2997 	 * The HCD might still restart the timer (if a port status change
2998 	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
2999 	 * the hub_status_data() callback.
3000 	 */
3001 	hcd->rh_pollable = 0;
3002 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
3003 	del_timer_sync(&hcd->rh_timer);
3004 
3005 	hcd->driver->stop(hcd);
3006 	hcd->state = HC_STATE_HALT;
3007 
3008 	/* In case the HCD restarted the timer, stop it again. */
3009 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
3010 	del_timer_sync(&hcd->rh_timer);
3011 
3012 	if (usb_hcd_is_primary_hcd(hcd)) {
3013 		if (hcd->irq > 0)
3014 			free_irq(hcd->irq, hcd);
3015 	}
3016 
3017 	usb_deregister_bus(&hcd->self);
3018 	hcd_buffer_destroy(hcd);
3019 
3020 	usb_phy_roothub_power_off(hcd->phy_roothub);
3021 	usb_phy_roothub_exit(hcd->phy_roothub);
3022 
3023 	usb_put_invalidate_rhdev(hcd);
3024 	hcd->flags = 0;
3025 }
3026 EXPORT_SYMBOL_GPL(usb_remove_hcd);
3027 
3028 void
3029 usb_hcd_platform_shutdown(struct platform_device *dev)
3030 {
3031 	struct usb_hcd *hcd = platform_get_drvdata(dev);
3032 
3033 	/* No need for pm_runtime_put(), we're shutting down */
3034 	pm_runtime_get_sync(&dev->dev);
3035 
3036 	if (hcd->driver->shutdown)
3037 		hcd->driver->shutdown(hcd);
3038 }
3039 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
3040 
3041 int usb_hcd_setup_local_mem(struct usb_hcd *hcd, phys_addr_t phys_addr,
3042 			    dma_addr_t dma, size_t size)
3043 {
3044 	int err;
3045 	void *local_mem;
3046 
3047 	hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, 4,
3048 						  dev_to_node(hcd->self.sysdev),
3049 						  dev_name(hcd->self.sysdev));
3050 	if (IS_ERR(hcd->localmem_pool))
3051 		return PTR_ERR(hcd->localmem_pool);
3052 
3053 	local_mem = devm_memremap(hcd->self.sysdev, phys_addr,
3054 				  size, MEMREMAP_WC);
3055 	if (IS_ERR(local_mem))
3056 		return PTR_ERR(local_mem);
3057 
3058 	/*
3059 	 * Here we pass a dma_addr_t but the arg type is a phys_addr_t.
3060 	 * It's not backed by system memory and thus there's no kernel mapping
3061 	 * for it.
3062 	 */
3063 	err = gen_pool_add_virt(hcd->localmem_pool, (unsigned long)local_mem,
3064 				dma, size, dev_to_node(hcd->self.sysdev));
3065 	if (err < 0) {
3066 		dev_err(hcd->self.sysdev, "gen_pool_add_virt failed with %d\n",
3067 			err);
3068 		return err;
3069 	}
3070 
3071 	return 0;
3072 }
3073 EXPORT_SYMBOL_GPL(usb_hcd_setup_local_mem);
3074 
3075 /*-------------------------------------------------------------------------*/
3076 
3077 #if IS_ENABLED(CONFIG_USB_MON)
3078 
3079 const struct usb_mon_operations *mon_ops;
3080 
3081 /*
3082  * The registration is unlocked.
3083  * We do it this way because we do not want to lock in hot paths.
3084  *
3085  * Notice that the code is minimally error-proof. Because usbmon needs
3086  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
3087  */
3088 
3089 int usb_mon_register(const struct usb_mon_operations *ops)
3090 {
3091 
3092 	if (mon_ops)
3093 		return -EBUSY;
3094 
3095 	mon_ops = ops;
3096 	mb();
3097 	return 0;
3098 }
3099 EXPORT_SYMBOL_GPL (usb_mon_register);
3100 
3101 void usb_mon_deregister (void)
3102 {
3103 
3104 	if (mon_ops == NULL) {
3105 		printk(KERN_ERR "USB: monitor was not registered\n");
3106 		return;
3107 	}
3108 	mon_ops = NULL;
3109 	mb();
3110 }
3111 EXPORT_SYMBOL_GPL (usb_mon_deregister);
3112 
3113 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
3114