xref: /openbmc/linux/drivers/usb/core/hcd.c (revision 15d90a6a)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright Linus Torvalds 1999
4  * (C) Copyright Johannes Erdfelt 1999-2001
5  * (C) Copyright Andreas Gal 1999
6  * (C) Copyright Gregory P. Smith 1999
7  * (C) Copyright Deti Fliegl 1999
8  * (C) Copyright Randy Dunlap 2000
9  * (C) Copyright David Brownell 2000-2002
10  */
11 
12 #include <linux/bcd.h>
13 #include <linux/module.h>
14 #include <linux/version.h>
15 #include <linux/kernel.h>
16 #include <linux/sched/task_stack.h>
17 #include <linux/slab.h>
18 #include <linux/completion.h>
19 #include <linux/utsname.h>
20 #include <linux/mm.h>
21 #include <asm/io.h>
22 #include <linux/device.h>
23 #include <linux/dma-mapping.h>
24 #include <linux/mutex.h>
25 #include <asm/irq.h>
26 #include <asm/byteorder.h>
27 #include <asm/unaligned.h>
28 #include <linux/platform_device.h>
29 #include <linux/workqueue.h>
30 #include <linux/pm_runtime.h>
31 #include <linux/types.h>
32 
33 #include <linux/phy/phy.h>
34 #include <linux/usb.h>
35 #include <linux/usb/hcd.h>
36 #include <linux/usb/otg.h>
37 
38 #include "usb.h"
39 #include "phy.h"
40 
41 
42 /*-------------------------------------------------------------------------*/
43 
44 /*
45  * USB Host Controller Driver framework
46  *
47  * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
48  * HCD-specific behaviors/bugs.
49  *
50  * This does error checks, tracks devices and urbs, and delegates to a
51  * "hc_driver" only for code (and data) that really needs to know about
52  * hardware differences.  That includes root hub registers, i/o queues,
53  * and so on ... but as little else as possible.
54  *
55  * Shared code includes most of the "root hub" code (these are emulated,
56  * though each HC's hardware works differently) and PCI glue, plus request
57  * tracking overhead.  The HCD code should only block on spinlocks or on
58  * hardware handshaking; blocking on software events (such as other kernel
59  * threads releasing resources, or completing actions) is all generic.
60  *
61  * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
62  * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
63  * only by the hub driver ... and that neither should be seen or used by
64  * usb client device drivers.
65  *
66  * Contributors of ideas or unattributed patches include: David Brownell,
67  * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
68  *
69  * HISTORY:
70  * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
71  *		associated cleanup.  "usb_hcd" still != "usb_bus".
72  * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
73  */
74 
75 /*-------------------------------------------------------------------------*/
76 
77 /* Keep track of which host controller drivers are loaded */
78 unsigned long usb_hcds_loaded;
79 EXPORT_SYMBOL_GPL(usb_hcds_loaded);
80 
81 /* host controllers we manage */
82 DEFINE_IDR (usb_bus_idr);
83 EXPORT_SYMBOL_GPL (usb_bus_idr);
84 
85 /* used when allocating bus numbers */
86 #define USB_MAXBUS		64
87 
88 /* used when updating list of hcds */
89 DEFINE_MUTEX(usb_bus_idr_lock);	/* exported only for usbfs */
90 EXPORT_SYMBOL_GPL (usb_bus_idr_lock);
91 
92 /* used for controlling access to virtual root hubs */
93 static DEFINE_SPINLOCK(hcd_root_hub_lock);
94 
95 /* used when updating an endpoint's URB list */
96 static DEFINE_SPINLOCK(hcd_urb_list_lock);
97 
98 /* used to protect against unlinking URBs after the device is gone */
99 static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
100 
101 /* wait queue for synchronous unlinks */
102 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
103 
104 static inline int is_root_hub(struct usb_device *udev)
105 {
106 	return (udev->parent == NULL);
107 }
108 
109 /*-------------------------------------------------------------------------*/
110 
111 /*
112  * Sharable chunks of root hub code.
113  */
114 
115 /*-------------------------------------------------------------------------*/
116 #define KERNEL_REL	bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff))
117 #define KERNEL_VER	bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff))
118 
119 /* usb 3.1 root hub device descriptor */
120 static const u8 usb31_rh_dev_descriptor[18] = {
121 	0x12,       /*  __u8  bLength; */
122 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
123 	0x10, 0x03, /*  __le16 bcdUSB; v3.1 */
124 
125 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
126 	0x00,	    /*  __u8  bDeviceSubClass; */
127 	0x03,       /*  __u8  bDeviceProtocol; USB 3 hub */
128 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
129 
130 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
131 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
132 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
133 
134 	0x03,       /*  __u8  iManufacturer; */
135 	0x02,       /*  __u8  iProduct; */
136 	0x01,       /*  __u8  iSerialNumber; */
137 	0x01        /*  __u8  bNumConfigurations; */
138 };
139 
140 /* usb 3.0 root hub device descriptor */
141 static const u8 usb3_rh_dev_descriptor[18] = {
142 	0x12,       /*  __u8  bLength; */
143 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
144 	0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
145 
146 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
147 	0x00,	    /*  __u8  bDeviceSubClass; */
148 	0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
149 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
150 
151 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
152 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
153 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
154 
155 	0x03,       /*  __u8  iManufacturer; */
156 	0x02,       /*  __u8  iProduct; */
157 	0x01,       /*  __u8  iSerialNumber; */
158 	0x01        /*  __u8  bNumConfigurations; */
159 };
160 
161 /* usb 2.5 (wireless USB 1.0) root hub device descriptor */
162 static const u8 usb25_rh_dev_descriptor[18] = {
163 	0x12,       /*  __u8  bLength; */
164 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
165 	0x50, 0x02, /*  __le16 bcdUSB; v2.5 */
166 
167 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
168 	0x00,	    /*  __u8  bDeviceSubClass; */
169 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
170 	0xFF,       /*  __u8  bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */
171 
172 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
173 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
174 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
175 
176 	0x03,       /*  __u8  iManufacturer; */
177 	0x02,       /*  __u8  iProduct; */
178 	0x01,       /*  __u8  iSerialNumber; */
179 	0x01        /*  __u8  bNumConfigurations; */
180 };
181 
182 /* usb 2.0 root hub device descriptor */
183 static const u8 usb2_rh_dev_descriptor[18] = {
184 	0x12,       /*  __u8  bLength; */
185 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
186 	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
187 
188 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
189 	0x00,	    /*  __u8  bDeviceSubClass; */
190 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
191 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
192 
193 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
194 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
195 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
196 
197 	0x03,       /*  __u8  iManufacturer; */
198 	0x02,       /*  __u8  iProduct; */
199 	0x01,       /*  __u8  iSerialNumber; */
200 	0x01        /*  __u8  bNumConfigurations; */
201 };
202 
203 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
204 
205 /* usb 1.1 root hub device descriptor */
206 static const u8 usb11_rh_dev_descriptor[18] = {
207 	0x12,       /*  __u8  bLength; */
208 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
209 	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
210 
211 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
212 	0x00,	    /*  __u8  bDeviceSubClass; */
213 	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
214 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
215 
216 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
217 	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
218 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
219 
220 	0x03,       /*  __u8  iManufacturer; */
221 	0x02,       /*  __u8  iProduct; */
222 	0x01,       /*  __u8  iSerialNumber; */
223 	0x01        /*  __u8  bNumConfigurations; */
224 };
225 
226 
227 /*-------------------------------------------------------------------------*/
228 
229 /* Configuration descriptors for our root hubs */
230 
231 static const u8 fs_rh_config_descriptor[] = {
232 
233 	/* one configuration */
234 	0x09,       /*  __u8  bLength; */
235 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
236 	0x19, 0x00, /*  __le16 wTotalLength; */
237 	0x01,       /*  __u8  bNumInterfaces; (1) */
238 	0x01,       /*  __u8  bConfigurationValue; */
239 	0x00,       /*  __u8  iConfiguration; */
240 	0xc0,       /*  __u8  bmAttributes;
241 				 Bit 7: must be set,
242 				     6: Self-powered,
243 				     5: Remote wakeup,
244 				     4..0: resvd */
245 	0x00,       /*  __u8  MaxPower; */
246 
247 	/* USB 1.1:
248 	 * USB 2.0, single TT organization (mandatory):
249 	 *	one interface, protocol 0
250 	 *
251 	 * USB 2.0, multiple TT organization (optional):
252 	 *	two interfaces, protocols 1 (like single TT)
253 	 *	and 2 (multiple TT mode) ... config is
254 	 *	sometimes settable
255 	 *	NOT IMPLEMENTED
256 	 */
257 
258 	/* one interface */
259 	0x09,       /*  __u8  if_bLength; */
260 	USB_DT_INTERFACE,  /* __u8 if_bDescriptorType; Interface */
261 	0x00,       /*  __u8  if_bInterfaceNumber; */
262 	0x00,       /*  __u8  if_bAlternateSetting; */
263 	0x01,       /*  __u8  if_bNumEndpoints; */
264 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
265 	0x00,       /*  __u8  if_bInterfaceSubClass; */
266 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
267 	0x00,       /*  __u8  if_iInterface; */
268 
269 	/* one endpoint (status change endpoint) */
270 	0x07,       /*  __u8  ep_bLength; */
271 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
272 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
273 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
274 	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
275 	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
276 };
277 
278 static const u8 hs_rh_config_descriptor[] = {
279 
280 	/* one configuration */
281 	0x09,       /*  __u8  bLength; */
282 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
283 	0x19, 0x00, /*  __le16 wTotalLength; */
284 	0x01,       /*  __u8  bNumInterfaces; (1) */
285 	0x01,       /*  __u8  bConfigurationValue; */
286 	0x00,       /*  __u8  iConfiguration; */
287 	0xc0,       /*  __u8  bmAttributes;
288 				 Bit 7: must be set,
289 				     6: Self-powered,
290 				     5: Remote wakeup,
291 				     4..0: resvd */
292 	0x00,       /*  __u8  MaxPower; */
293 
294 	/* USB 1.1:
295 	 * USB 2.0, single TT organization (mandatory):
296 	 *	one interface, protocol 0
297 	 *
298 	 * USB 2.0, multiple TT organization (optional):
299 	 *	two interfaces, protocols 1 (like single TT)
300 	 *	and 2 (multiple TT mode) ... config is
301 	 *	sometimes settable
302 	 *	NOT IMPLEMENTED
303 	 */
304 
305 	/* one interface */
306 	0x09,       /*  __u8  if_bLength; */
307 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
308 	0x00,       /*  __u8  if_bInterfaceNumber; */
309 	0x00,       /*  __u8  if_bAlternateSetting; */
310 	0x01,       /*  __u8  if_bNumEndpoints; */
311 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
312 	0x00,       /*  __u8  if_bInterfaceSubClass; */
313 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
314 	0x00,       /*  __u8  if_iInterface; */
315 
316 	/* one endpoint (status change endpoint) */
317 	0x07,       /*  __u8  ep_bLength; */
318 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
319 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
320 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
321 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
322 		     * see hub.c:hub_configure() for details. */
323 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
324 	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
325 };
326 
327 static const u8 ss_rh_config_descriptor[] = {
328 	/* one configuration */
329 	0x09,       /*  __u8  bLength; */
330 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
331 	0x1f, 0x00, /*  __le16 wTotalLength; */
332 	0x01,       /*  __u8  bNumInterfaces; (1) */
333 	0x01,       /*  __u8  bConfigurationValue; */
334 	0x00,       /*  __u8  iConfiguration; */
335 	0xc0,       /*  __u8  bmAttributes;
336 				 Bit 7: must be set,
337 				     6: Self-powered,
338 				     5: Remote wakeup,
339 				     4..0: resvd */
340 	0x00,       /*  __u8  MaxPower; */
341 
342 	/* one interface */
343 	0x09,       /*  __u8  if_bLength; */
344 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
345 	0x00,       /*  __u8  if_bInterfaceNumber; */
346 	0x00,       /*  __u8  if_bAlternateSetting; */
347 	0x01,       /*  __u8  if_bNumEndpoints; */
348 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
349 	0x00,       /*  __u8  if_bInterfaceSubClass; */
350 	0x00,       /*  __u8  if_bInterfaceProtocol; */
351 	0x00,       /*  __u8  if_iInterface; */
352 
353 	/* one endpoint (status change endpoint) */
354 	0x07,       /*  __u8  ep_bLength; */
355 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
356 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
357 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
358 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
359 		     * see hub.c:hub_configure() for details. */
360 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
361 	0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
362 
363 	/* one SuperSpeed endpoint companion descriptor */
364 	0x06,        /* __u8 ss_bLength */
365 	USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */
366 		     /* Companion */
367 	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
368 	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
369 	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
370 };
371 
372 /* authorized_default behaviour:
373  * -1 is authorized for all devices except wireless (old behaviour)
374  * 0 is unauthorized for all devices
375  * 1 is authorized for all devices
376  */
377 static int authorized_default = -1;
378 module_param(authorized_default, int, S_IRUGO|S_IWUSR);
379 MODULE_PARM_DESC(authorized_default,
380 		"Default USB device authorization: 0 is not authorized, 1 is "
381 		"authorized, -1 is authorized except for wireless USB (default, "
382 		"old behaviour");
383 /*-------------------------------------------------------------------------*/
384 
385 /**
386  * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
387  * @s: Null-terminated ASCII (actually ISO-8859-1) string
388  * @buf: Buffer for USB string descriptor (header + UTF-16LE)
389  * @len: Length (in bytes; may be odd) of descriptor buffer.
390  *
391  * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
392  * whichever is less.
393  *
394  * Note:
395  * USB String descriptors can contain at most 126 characters; input
396  * strings longer than that are truncated.
397  */
398 static unsigned
399 ascii2desc(char const *s, u8 *buf, unsigned len)
400 {
401 	unsigned n, t = 2 + 2*strlen(s);
402 
403 	if (t > 254)
404 		t = 254;	/* Longest possible UTF string descriptor */
405 	if (len > t)
406 		len = t;
407 
408 	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
409 
410 	n = len;
411 	while (n--) {
412 		*buf++ = t;
413 		if (!n--)
414 			break;
415 		*buf++ = t >> 8;
416 		t = (unsigned char)*s++;
417 	}
418 	return len;
419 }
420 
421 /**
422  * rh_string() - provides string descriptors for root hub
423  * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
424  * @hcd: the host controller for this root hub
425  * @data: buffer for output packet
426  * @len: length of the provided buffer
427  *
428  * Produces either a manufacturer, product or serial number string for the
429  * virtual root hub device.
430  *
431  * Return: The number of bytes filled in: the length of the descriptor or
432  * of the provided buffer, whichever is less.
433  */
434 static unsigned
435 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
436 {
437 	char buf[100];
438 	char const *s;
439 	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
440 
441 	/* language ids */
442 	switch (id) {
443 	case 0:
444 		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
445 		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
446 		if (len > 4)
447 			len = 4;
448 		memcpy(data, langids, len);
449 		return len;
450 	case 1:
451 		/* Serial number */
452 		s = hcd->self.bus_name;
453 		break;
454 	case 2:
455 		/* Product name */
456 		s = hcd->product_desc;
457 		break;
458 	case 3:
459 		/* Manufacturer */
460 		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
461 			init_utsname()->release, hcd->driver->description);
462 		s = buf;
463 		break;
464 	default:
465 		/* Can't happen; caller guarantees it */
466 		return 0;
467 	}
468 
469 	return ascii2desc(s, data, len);
470 }
471 
472 
473 /* Root hub control transfers execute synchronously */
474 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
475 {
476 	struct usb_ctrlrequest *cmd;
477 	u16		typeReq, wValue, wIndex, wLength;
478 	u8		*ubuf = urb->transfer_buffer;
479 	unsigned	len = 0;
480 	int		status;
481 	u8		patch_wakeup = 0;
482 	u8		patch_protocol = 0;
483 	u16		tbuf_size;
484 	u8		*tbuf = NULL;
485 	const u8	*bufp;
486 
487 	might_sleep();
488 
489 	spin_lock_irq(&hcd_root_hub_lock);
490 	status = usb_hcd_link_urb_to_ep(hcd, urb);
491 	spin_unlock_irq(&hcd_root_hub_lock);
492 	if (status)
493 		return status;
494 	urb->hcpriv = hcd;	/* Indicate it's queued */
495 
496 	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
497 	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
498 	wValue   = le16_to_cpu (cmd->wValue);
499 	wIndex   = le16_to_cpu (cmd->wIndex);
500 	wLength  = le16_to_cpu (cmd->wLength);
501 
502 	if (wLength > urb->transfer_buffer_length)
503 		goto error;
504 
505 	/*
506 	 * tbuf should be at least as big as the
507 	 * USB hub descriptor.
508 	 */
509 	tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
510 	tbuf = kzalloc(tbuf_size, GFP_KERNEL);
511 	if (!tbuf) {
512 		status = -ENOMEM;
513 		goto err_alloc;
514 	}
515 
516 	bufp = tbuf;
517 
518 
519 	urb->actual_length = 0;
520 	switch (typeReq) {
521 
522 	/* DEVICE REQUESTS */
523 
524 	/* The root hub's remote wakeup enable bit is implemented using
525 	 * driver model wakeup flags.  If this system supports wakeup
526 	 * through USB, userspace may change the default "allow wakeup"
527 	 * policy through sysfs or these calls.
528 	 *
529 	 * Most root hubs support wakeup from downstream devices, for
530 	 * runtime power management (disabling USB clocks and reducing
531 	 * VBUS power usage).  However, not all of them do so; silicon,
532 	 * board, and BIOS bugs here are not uncommon, so these can't
533 	 * be treated quite like external hubs.
534 	 *
535 	 * Likewise, not all root hubs will pass wakeup events upstream,
536 	 * to wake up the whole system.  So don't assume root hub and
537 	 * controller capabilities are identical.
538 	 */
539 
540 	case DeviceRequest | USB_REQ_GET_STATUS:
541 		tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
542 					<< USB_DEVICE_REMOTE_WAKEUP)
543 				| (1 << USB_DEVICE_SELF_POWERED);
544 		tbuf[1] = 0;
545 		len = 2;
546 		break;
547 	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
548 		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
549 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
550 		else
551 			goto error;
552 		break;
553 	case DeviceOutRequest | USB_REQ_SET_FEATURE:
554 		if (device_can_wakeup(&hcd->self.root_hub->dev)
555 				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
556 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
557 		else
558 			goto error;
559 		break;
560 	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
561 		tbuf[0] = 1;
562 		len = 1;
563 			/* FALLTHROUGH */
564 	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
565 		break;
566 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
567 		switch (wValue & 0xff00) {
568 		case USB_DT_DEVICE << 8:
569 			switch (hcd->speed) {
570 			case HCD_USB32:
571 			case HCD_USB31:
572 				bufp = usb31_rh_dev_descriptor;
573 				break;
574 			case HCD_USB3:
575 				bufp = usb3_rh_dev_descriptor;
576 				break;
577 			case HCD_USB25:
578 				bufp = usb25_rh_dev_descriptor;
579 				break;
580 			case HCD_USB2:
581 				bufp = usb2_rh_dev_descriptor;
582 				break;
583 			case HCD_USB11:
584 				bufp = usb11_rh_dev_descriptor;
585 				break;
586 			default:
587 				goto error;
588 			}
589 			len = 18;
590 			if (hcd->has_tt)
591 				patch_protocol = 1;
592 			break;
593 		case USB_DT_CONFIG << 8:
594 			switch (hcd->speed) {
595 			case HCD_USB32:
596 			case HCD_USB31:
597 			case HCD_USB3:
598 				bufp = ss_rh_config_descriptor;
599 				len = sizeof ss_rh_config_descriptor;
600 				break;
601 			case HCD_USB25:
602 			case HCD_USB2:
603 				bufp = hs_rh_config_descriptor;
604 				len = sizeof hs_rh_config_descriptor;
605 				break;
606 			case HCD_USB11:
607 				bufp = fs_rh_config_descriptor;
608 				len = sizeof fs_rh_config_descriptor;
609 				break;
610 			default:
611 				goto error;
612 			}
613 			if (device_can_wakeup(&hcd->self.root_hub->dev))
614 				patch_wakeup = 1;
615 			break;
616 		case USB_DT_STRING << 8:
617 			if ((wValue & 0xff) < 4)
618 				urb->actual_length = rh_string(wValue & 0xff,
619 						hcd, ubuf, wLength);
620 			else /* unsupported IDs --> "protocol stall" */
621 				goto error;
622 			break;
623 		case USB_DT_BOS << 8:
624 			goto nongeneric;
625 		default:
626 			goto error;
627 		}
628 		break;
629 	case DeviceRequest | USB_REQ_GET_INTERFACE:
630 		tbuf[0] = 0;
631 		len = 1;
632 			/* FALLTHROUGH */
633 	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
634 		break;
635 	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
636 		/* wValue == urb->dev->devaddr */
637 		dev_dbg (hcd->self.controller, "root hub device address %d\n",
638 			wValue);
639 		break;
640 
641 	/* INTERFACE REQUESTS (no defined feature/status flags) */
642 
643 	/* ENDPOINT REQUESTS */
644 
645 	case EndpointRequest | USB_REQ_GET_STATUS:
646 		/* ENDPOINT_HALT flag */
647 		tbuf[0] = 0;
648 		tbuf[1] = 0;
649 		len = 2;
650 			/* FALLTHROUGH */
651 	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
652 	case EndpointOutRequest | USB_REQ_SET_FEATURE:
653 		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
654 		break;
655 
656 	/* CLASS REQUESTS (and errors) */
657 
658 	default:
659 nongeneric:
660 		/* non-generic request */
661 		switch (typeReq) {
662 		case GetHubStatus:
663 			len = 4;
664 			break;
665 		case GetPortStatus:
666 			if (wValue == HUB_PORT_STATUS)
667 				len = 4;
668 			else
669 				/* other port status types return 8 bytes */
670 				len = 8;
671 			break;
672 		case GetHubDescriptor:
673 			len = sizeof (struct usb_hub_descriptor);
674 			break;
675 		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
676 			/* len is returned by hub_control */
677 			break;
678 		}
679 		status = hcd->driver->hub_control (hcd,
680 			typeReq, wValue, wIndex,
681 			tbuf, wLength);
682 
683 		if (typeReq == GetHubDescriptor)
684 			usb_hub_adjust_deviceremovable(hcd->self.root_hub,
685 				(struct usb_hub_descriptor *)tbuf);
686 		break;
687 error:
688 		/* "protocol stall" on error */
689 		status = -EPIPE;
690 	}
691 
692 	if (status < 0) {
693 		len = 0;
694 		if (status != -EPIPE) {
695 			dev_dbg (hcd->self.controller,
696 				"CTRL: TypeReq=0x%x val=0x%x "
697 				"idx=0x%x len=%d ==> %d\n",
698 				typeReq, wValue, wIndex,
699 				wLength, status);
700 		}
701 	} else if (status > 0) {
702 		/* hub_control may return the length of data copied. */
703 		len = status;
704 		status = 0;
705 	}
706 	if (len) {
707 		if (urb->transfer_buffer_length < len)
708 			len = urb->transfer_buffer_length;
709 		urb->actual_length = len;
710 		/* always USB_DIR_IN, toward host */
711 		memcpy (ubuf, bufp, len);
712 
713 		/* report whether RH hardware supports remote wakeup */
714 		if (patch_wakeup &&
715 				len > offsetof (struct usb_config_descriptor,
716 						bmAttributes))
717 			((struct usb_config_descriptor *)ubuf)->bmAttributes
718 				|= USB_CONFIG_ATT_WAKEUP;
719 
720 		/* report whether RH hardware has an integrated TT */
721 		if (patch_protocol &&
722 				len > offsetof(struct usb_device_descriptor,
723 						bDeviceProtocol))
724 			((struct usb_device_descriptor *) ubuf)->
725 				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
726 	}
727 
728 	kfree(tbuf);
729  err_alloc:
730 
731 	/* any errors get returned through the urb completion */
732 	spin_lock_irq(&hcd_root_hub_lock);
733 	usb_hcd_unlink_urb_from_ep(hcd, urb);
734 	usb_hcd_giveback_urb(hcd, urb, status);
735 	spin_unlock_irq(&hcd_root_hub_lock);
736 	return 0;
737 }
738 
739 /*-------------------------------------------------------------------------*/
740 
741 /*
742  * Root Hub interrupt transfers are polled using a timer if the
743  * driver requests it; otherwise the driver is responsible for
744  * calling usb_hcd_poll_rh_status() when an event occurs.
745  *
746  * Completions are called in_interrupt(), but they may or may not
747  * be in_irq().
748  */
749 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
750 {
751 	struct urb	*urb;
752 	int		length;
753 	unsigned long	flags;
754 	char		buffer[6];	/* Any root hubs with > 31 ports? */
755 
756 	if (unlikely(!hcd->rh_pollable))
757 		return;
758 	if (!hcd->uses_new_polling && !hcd->status_urb)
759 		return;
760 
761 	length = hcd->driver->hub_status_data(hcd, buffer);
762 	if (length > 0) {
763 
764 		/* try to complete the status urb */
765 		spin_lock_irqsave(&hcd_root_hub_lock, flags);
766 		urb = hcd->status_urb;
767 		if (urb) {
768 			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
769 			hcd->status_urb = NULL;
770 			urb->actual_length = length;
771 			memcpy(urb->transfer_buffer, buffer, length);
772 
773 			usb_hcd_unlink_urb_from_ep(hcd, urb);
774 			usb_hcd_giveback_urb(hcd, urb, 0);
775 		} else {
776 			length = 0;
777 			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
778 		}
779 		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
780 	}
781 
782 	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
783 	 * exceed that limit if HZ is 100. The math is more clunky than
784 	 * maybe expected, this is to make sure that all timers for USB devices
785 	 * fire at the same time to give the CPU a break in between */
786 	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
787 			(length == 0 && hcd->status_urb != NULL))
788 		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
789 }
790 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
791 
792 /* timer callback */
793 static void rh_timer_func (struct timer_list *t)
794 {
795 	struct usb_hcd *_hcd = from_timer(_hcd, t, rh_timer);
796 
797 	usb_hcd_poll_rh_status(_hcd);
798 }
799 
800 /*-------------------------------------------------------------------------*/
801 
802 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
803 {
804 	int		retval;
805 	unsigned long	flags;
806 	unsigned	len = 1 + (urb->dev->maxchild / 8);
807 
808 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
809 	if (hcd->status_urb || urb->transfer_buffer_length < len) {
810 		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
811 		retval = -EINVAL;
812 		goto done;
813 	}
814 
815 	retval = usb_hcd_link_urb_to_ep(hcd, urb);
816 	if (retval)
817 		goto done;
818 
819 	hcd->status_urb = urb;
820 	urb->hcpriv = hcd;	/* indicate it's queued */
821 	if (!hcd->uses_new_polling)
822 		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
823 
824 	/* If a status change has already occurred, report it ASAP */
825 	else if (HCD_POLL_PENDING(hcd))
826 		mod_timer(&hcd->rh_timer, jiffies);
827 	retval = 0;
828  done:
829 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
830 	return retval;
831 }
832 
833 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
834 {
835 	if (usb_endpoint_xfer_int(&urb->ep->desc))
836 		return rh_queue_status (hcd, urb);
837 	if (usb_endpoint_xfer_control(&urb->ep->desc))
838 		return rh_call_control (hcd, urb);
839 	return -EINVAL;
840 }
841 
842 /*-------------------------------------------------------------------------*/
843 
844 /* Unlinks of root-hub control URBs are legal, but they don't do anything
845  * since these URBs always execute synchronously.
846  */
847 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
848 {
849 	unsigned long	flags;
850 	int		rc;
851 
852 	spin_lock_irqsave(&hcd_root_hub_lock, flags);
853 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
854 	if (rc)
855 		goto done;
856 
857 	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
858 		;	/* Do nothing */
859 
860 	} else {				/* Status URB */
861 		if (!hcd->uses_new_polling)
862 			del_timer (&hcd->rh_timer);
863 		if (urb == hcd->status_urb) {
864 			hcd->status_urb = NULL;
865 			usb_hcd_unlink_urb_from_ep(hcd, urb);
866 			usb_hcd_giveback_urb(hcd, urb, status);
867 		}
868 	}
869  done:
870 	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
871 	return rc;
872 }
873 
874 
875 
876 /*
877  * Show & store the current value of authorized_default
878  */
879 static ssize_t authorized_default_show(struct device *dev,
880 				       struct device_attribute *attr, char *buf)
881 {
882 	struct usb_device *rh_usb_dev = to_usb_device(dev);
883 	struct usb_bus *usb_bus = rh_usb_dev->bus;
884 	struct usb_hcd *hcd;
885 
886 	hcd = bus_to_hcd(usb_bus);
887 	return snprintf(buf, PAGE_SIZE, "%u\n", !!HCD_DEV_AUTHORIZED(hcd));
888 }
889 
890 static ssize_t authorized_default_store(struct device *dev,
891 					struct device_attribute *attr,
892 					const char *buf, size_t size)
893 {
894 	ssize_t result;
895 	unsigned val;
896 	struct usb_device *rh_usb_dev = to_usb_device(dev);
897 	struct usb_bus *usb_bus = rh_usb_dev->bus;
898 	struct usb_hcd *hcd;
899 
900 	hcd = bus_to_hcd(usb_bus);
901 	result = sscanf(buf, "%u\n", &val);
902 	if (result == 1) {
903 		if (val)
904 			set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
905 		else
906 			clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
907 
908 		result = size;
909 	} else {
910 		result = -EINVAL;
911 	}
912 	return result;
913 }
914 static DEVICE_ATTR_RW(authorized_default);
915 
916 /*
917  * interface_authorized_default_show - show default authorization status
918  * for USB interfaces
919  *
920  * note: interface_authorized_default is the default value
921  *       for initializing the authorized attribute of interfaces
922  */
923 static ssize_t interface_authorized_default_show(struct device *dev,
924 		struct device_attribute *attr, char *buf)
925 {
926 	struct usb_device *usb_dev = to_usb_device(dev);
927 	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
928 
929 	return sprintf(buf, "%u\n", !!HCD_INTF_AUTHORIZED(hcd));
930 }
931 
932 /*
933  * interface_authorized_default_store - store default authorization status
934  * for USB interfaces
935  *
936  * note: interface_authorized_default is the default value
937  *       for initializing the authorized attribute of interfaces
938  */
939 static ssize_t interface_authorized_default_store(struct device *dev,
940 		struct device_attribute *attr, const char *buf, size_t count)
941 {
942 	struct usb_device *usb_dev = to_usb_device(dev);
943 	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
944 	int rc = count;
945 	bool val;
946 
947 	if (strtobool(buf, &val) != 0)
948 		return -EINVAL;
949 
950 	if (val)
951 		set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
952 	else
953 		clear_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
954 
955 	return rc;
956 }
957 static DEVICE_ATTR_RW(interface_authorized_default);
958 
959 /* Group all the USB bus attributes */
960 static struct attribute *usb_bus_attrs[] = {
961 		&dev_attr_authorized_default.attr,
962 		&dev_attr_interface_authorized_default.attr,
963 		NULL,
964 };
965 
966 static const struct attribute_group usb_bus_attr_group = {
967 	.name = NULL,	/* we want them in the same directory */
968 	.attrs = usb_bus_attrs,
969 };
970 
971 
972 
973 /*-------------------------------------------------------------------------*/
974 
975 /**
976  * usb_bus_init - shared initialization code
977  * @bus: the bus structure being initialized
978  *
979  * This code is used to initialize a usb_bus structure, memory for which is
980  * separately managed.
981  */
982 static void usb_bus_init (struct usb_bus *bus)
983 {
984 	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
985 
986 	bus->devnum_next = 1;
987 
988 	bus->root_hub = NULL;
989 	bus->busnum = -1;
990 	bus->bandwidth_allocated = 0;
991 	bus->bandwidth_int_reqs  = 0;
992 	bus->bandwidth_isoc_reqs = 0;
993 	mutex_init(&bus->devnum_next_mutex);
994 }
995 
996 /*-------------------------------------------------------------------------*/
997 
998 /**
999  * usb_register_bus - registers the USB host controller with the usb core
1000  * @bus: pointer to the bus to register
1001  * Context: !in_interrupt()
1002  *
1003  * Assigns a bus number, and links the controller into usbcore data
1004  * structures so that it can be seen by scanning the bus list.
1005  *
1006  * Return: 0 if successful. A negative error code otherwise.
1007  */
1008 static int usb_register_bus(struct usb_bus *bus)
1009 {
1010 	int result = -E2BIG;
1011 	int busnum;
1012 
1013 	mutex_lock(&usb_bus_idr_lock);
1014 	busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL);
1015 	if (busnum < 0) {
1016 		pr_err("%s: failed to get bus number\n", usbcore_name);
1017 		goto error_find_busnum;
1018 	}
1019 	bus->busnum = busnum;
1020 	mutex_unlock(&usb_bus_idr_lock);
1021 
1022 	usb_notify_add_bus(bus);
1023 
1024 	dev_info (bus->controller, "new USB bus registered, assigned bus "
1025 		  "number %d\n", bus->busnum);
1026 	return 0;
1027 
1028 error_find_busnum:
1029 	mutex_unlock(&usb_bus_idr_lock);
1030 	return result;
1031 }
1032 
1033 /**
1034  * usb_deregister_bus - deregisters the USB host controller
1035  * @bus: pointer to the bus to deregister
1036  * Context: !in_interrupt()
1037  *
1038  * Recycles the bus number, and unlinks the controller from usbcore data
1039  * structures so that it won't be seen by scanning the bus list.
1040  */
1041 static void usb_deregister_bus (struct usb_bus *bus)
1042 {
1043 	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
1044 
1045 	/*
1046 	 * NOTE: make sure that all the devices are removed by the
1047 	 * controller code, as well as having it call this when cleaning
1048 	 * itself up
1049 	 */
1050 	mutex_lock(&usb_bus_idr_lock);
1051 	idr_remove(&usb_bus_idr, bus->busnum);
1052 	mutex_unlock(&usb_bus_idr_lock);
1053 
1054 	usb_notify_remove_bus(bus);
1055 }
1056 
1057 /**
1058  * register_root_hub - called by usb_add_hcd() to register a root hub
1059  * @hcd: host controller for this root hub
1060  *
1061  * This function registers the root hub with the USB subsystem.  It sets up
1062  * the device properly in the device tree and then calls usb_new_device()
1063  * to register the usb device.  It also assigns the root hub's USB address
1064  * (always 1).
1065  *
1066  * Return: 0 if successful. A negative error code otherwise.
1067  */
1068 static int register_root_hub(struct usb_hcd *hcd)
1069 {
1070 	struct device *parent_dev = hcd->self.controller;
1071 	struct usb_device *usb_dev = hcd->self.root_hub;
1072 	const int devnum = 1;
1073 	int retval;
1074 
1075 	usb_dev->devnum = devnum;
1076 	usb_dev->bus->devnum_next = devnum + 1;
1077 	set_bit (devnum, usb_dev->bus->devmap.devicemap);
1078 	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
1079 
1080 	mutex_lock(&usb_bus_idr_lock);
1081 
1082 	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
1083 	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
1084 	if (retval != sizeof usb_dev->descriptor) {
1085 		mutex_unlock(&usb_bus_idr_lock);
1086 		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
1087 				dev_name(&usb_dev->dev), retval);
1088 		return (retval < 0) ? retval : -EMSGSIZE;
1089 	}
1090 
1091 	if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
1092 		retval = usb_get_bos_descriptor(usb_dev);
1093 		if (!retval) {
1094 			usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
1095 		} else if (usb_dev->speed >= USB_SPEED_SUPER) {
1096 			mutex_unlock(&usb_bus_idr_lock);
1097 			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1098 					dev_name(&usb_dev->dev), retval);
1099 			return retval;
1100 		}
1101 	}
1102 
1103 	retval = usb_new_device (usb_dev);
1104 	if (retval) {
1105 		dev_err (parent_dev, "can't register root hub for %s, %d\n",
1106 				dev_name(&usb_dev->dev), retval);
1107 	} else {
1108 		spin_lock_irq (&hcd_root_hub_lock);
1109 		hcd->rh_registered = 1;
1110 		spin_unlock_irq (&hcd_root_hub_lock);
1111 
1112 		/* Did the HC die before the root hub was registered? */
1113 		if (HCD_DEAD(hcd))
1114 			usb_hc_died (hcd);	/* This time clean up */
1115 	}
1116 	mutex_unlock(&usb_bus_idr_lock);
1117 
1118 	return retval;
1119 }
1120 
1121 /*
1122  * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1123  * @bus: the bus which the root hub belongs to
1124  * @portnum: the port which is being resumed
1125  *
1126  * HCDs should call this function when they know that a resume signal is
1127  * being sent to a root-hub port.  The root hub will be prevented from
1128  * going into autosuspend until usb_hcd_end_port_resume() is called.
1129  *
1130  * The bus's private lock must be held by the caller.
1131  */
1132 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1133 {
1134 	unsigned bit = 1 << portnum;
1135 
1136 	if (!(bus->resuming_ports & bit)) {
1137 		bus->resuming_ports |= bit;
1138 		pm_runtime_get_noresume(&bus->root_hub->dev);
1139 	}
1140 }
1141 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1142 
1143 /*
1144  * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1145  * @bus: the bus which the root hub belongs to
1146  * @portnum: the port which is being resumed
1147  *
1148  * HCDs should call this function when they know that a resume signal has
1149  * stopped being sent to a root-hub port.  The root hub will be allowed to
1150  * autosuspend again.
1151  *
1152  * The bus's private lock must be held by the caller.
1153  */
1154 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1155 {
1156 	unsigned bit = 1 << portnum;
1157 
1158 	if (bus->resuming_ports & bit) {
1159 		bus->resuming_ports &= ~bit;
1160 		pm_runtime_put_noidle(&bus->root_hub->dev);
1161 	}
1162 }
1163 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1164 
1165 /*-------------------------------------------------------------------------*/
1166 
1167 /**
1168  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1169  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1170  * @is_input: true iff the transaction sends data to the host
1171  * @isoc: true for isochronous transactions, false for interrupt ones
1172  * @bytecount: how many bytes in the transaction.
1173  *
1174  * Return: Approximate bus time in nanoseconds for a periodic transaction.
1175  *
1176  * Note:
1177  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1178  * scheduled in software, this function is only used for such scheduling.
1179  */
1180 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1181 {
1182 	unsigned long	tmp;
1183 
1184 	switch (speed) {
1185 	case USB_SPEED_LOW: 	/* INTR only */
1186 		if (is_input) {
1187 			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1188 			return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1189 		} else {
1190 			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1191 			return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1192 		}
1193 	case USB_SPEED_FULL:	/* ISOC or INTR */
1194 		if (isoc) {
1195 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1196 			return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1197 		} else {
1198 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1199 			return 9107L + BW_HOST_DELAY + tmp;
1200 		}
1201 	case USB_SPEED_HIGH:	/* ISOC or INTR */
1202 		/* FIXME adjust for input vs output */
1203 		if (isoc)
1204 			tmp = HS_NSECS_ISO (bytecount);
1205 		else
1206 			tmp = HS_NSECS (bytecount);
1207 		return tmp;
1208 	default:
1209 		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1210 		return -1;
1211 	}
1212 }
1213 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1214 
1215 
1216 /*-------------------------------------------------------------------------*/
1217 
1218 /*
1219  * Generic HC operations.
1220  */
1221 
1222 /*-------------------------------------------------------------------------*/
1223 
1224 /**
1225  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1226  * @hcd: host controller to which @urb was submitted
1227  * @urb: URB being submitted
1228  *
1229  * Host controller drivers should call this routine in their enqueue()
1230  * method.  The HCD's private spinlock must be held and interrupts must
1231  * be disabled.  The actions carried out here are required for URB
1232  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1233  *
1234  * Return: 0 for no error, otherwise a negative error code (in which case
1235  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1236  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1237  * the private spinlock and returning.
1238  */
1239 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1240 {
1241 	int		rc = 0;
1242 
1243 	spin_lock(&hcd_urb_list_lock);
1244 
1245 	/* Check that the URB isn't being killed */
1246 	if (unlikely(atomic_read(&urb->reject))) {
1247 		rc = -EPERM;
1248 		goto done;
1249 	}
1250 
1251 	if (unlikely(!urb->ep->enabled)) {
1252 		rc = -ENOENT;
1253 		goto done;
1254 	}
1255 
1256 	if (unlikely(!urb->dev->can_submit)) {
1257 		rc = -EHOSTUNREACH;
1258 		goto done;
1259 	}
1260 
1261 	/*
1262 	 * Check the host controller's state and add the URB to the
1263 	 * endpoint's queue.
1264 	 */
1265 	if (HCD_RH_RUNNING(hcd)) {
1266 		urb->unlinked = 0;
1267 		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1268 	} else {
1269 		rc = -ESHUTDOWN;
1270 		goto done;
1271 	}
1272  done:
1273 	spin_unlock(&hcd_urb_list_lock);
1274 	return rc;
1275 }
1276 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1277 
1278 /**
1279  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1280  * @hcd: host controller to which @urb was submitted
1281  * @urb: URB being checked for unlinkability
1282  * @status: error code to store in @urb if the unlink succeeds
1283  *
1284  * Host controller drivers should call this routine in their dequeue()
1285  * method.  The HCD's private spinlock must be held and interrupts must
1286  * be disabled.  The actions carried out here are required for making
1287  * sure than an unlink is valid.
1288  *
1289  * Return: 0 for no error, otherwise a negative error code (in which case
1290  * the dequeue() method must fail).  The possible error codes are:
1291  *
1292  *	-EIDRM: @urb was not submitted or has already completed.
1293  *		The completion function may not have been called yet.
1294  *
1295  *	-EBUSY: @urb has already been unlinked.
1296  */
1297 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1298 		int status)
1299 {
1300 	struct list_head	*tmp;
1301 
1302 	/* insist the urb is still queued */
1303 	list_for_each(tmp, &urb->ep->urb_list) {
1304 		if (tmp == &urb->urb_list)
1305 			break;
1306 	}
1307 	if (tmp != &urb->urb_list)
1308 		return -EIDRM;
1309 
1310 	/* Any status except -EINPROGRESS means something already started to
1311 	 * unlink this URB from the hardware.  So there's no more work to do.
1312 	 */
1313 	if (urb->unlinked)
1314 		return -EBUSY;
1315 	urb->unlinked = status;
1316 	return 0;
1317 }
1318 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1319 
1320 /**
1321  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1322  * @hcd: host controller to which @urb was submitted
1323  * @urb: URB being unlinked
1324  *
1325  * Host controller drivers should call this routine before calling
1326  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1327  * interrupts must be disabled.  The actions carried out here are required
1328  * for URB completion.
1329  */
1330 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1331 {
1332 	/* clear all state linking urb to this dev (and hcd) */
1333 	spin_lock(&hcd_urb_list_lock);
1334 	list_del_init(&urb->urb_list);
1335 	spin_unlock(&hcd_urb_list_lock);
1336 }
1337 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1338 
1339 /*
1340  * Some usb host controllers can only perform dma using a small SRAM area.
1341  * The usb core itself is however optimized for host controllers that can dma
1342  * using regular system memory - like pci devices doing bus mastering.
1343  *
1344  * To support host controllers with limited dma capabilities we provide dma
1345  * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag.
1346  * For this to work properly the host controller code must first use the
1347  * function dma_declare_coherent_memory() to point out which memory area
1348  * that should be used for dma allocations.
1349  *
1350  * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for
1351  * dma using dma_alloc_coherent() which in turn allocates from the memory
1352  * area pointed out with dma_declare_coherent_memory().
1353  *
1354  * So, to summarize...
1355  *
1356  * - We need "local" memory, canonical example being
1357  *   a small SRAM on a discrete controller being the
1358  *   only memory that the controller can read ...
1359  *   (a) "normal" kernel memory is no good, and
1360  *   (b) there's not enough to share
1361  *
1362  * - The only *portable* hook for such stuff in the
1363  *   DMA framework is dma_declare_coherent_memory()
1364  *
1365  * - So we use that, even though the primary requirement
1366  *   is that the memory be "local" (hence addressable
1367  *   by that device), not "coherent".
1368  *
1369  */
1370 
1371 static int hcd_alloc_coherent(struct usb_bus *bus,
1372 			      gfp_t mem_flags, dma_addr_t *dma_handle,
1373 			      void **vaddr_handle, size_t size,
1374 			      enum dma_data_direction dir)
1375 {
1376 	unsigned char *vaddr;
1377 
1378 	if (*vaddr_handle == NULL) {
1379 		WARN_ON_ONCE(1);
1380 		return -EFAULT;
1381 	}
1382 
1383 	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1384 				 mem_flags, dma_handle);
1385 	if (!vaddr)
1386 		return -ENOMEM;
1387 
1388 	/*
1389 	 * Store the virtual address of the buffer at the end
1390 	 * of the allocated dma buffer. The size of the buffer
1391 	 * may be uneven so use unaligned functions instead
1392 	 * of just rounding up. It makes sense to optimize for
1393 	 * memory footprint over access speed since the amount
1394 	 * of memory available for dma may be limited.
1395 	 */
1396 	put_unaligned((unsigned long)*vaddr_handle,
1397 		      (unsigned long *)(vaddr + size));
1398 
1399 	if (dir == DMA_TO_DEVICE)
1400 		memcpy(vaddr, *vaddr_handle, size);
1401 
1402 	*vaddr_handle = vaddr;
1403 	return 0;
1404 }
1405 
1406 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1407 			      void **vaddr_handle, size_t size,
1408 			      enum dma_data_direction dir)
1409 {
1410 	unsigned char *vaddr = *vaddr_handle;
1411 
1412 	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1413 
1414 	if (dir == DMA_FROM_DEVICE)
1415 		memcpy(vaddr, *vaddr_handle, size);
1416 
1417 	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1418 
1419 	*vaddr_handle = vaddr;
1420 	*dma_handle = 0;
1421 }
1422 
1423 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1424 {
1425 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1426 	    (urb->transfer_flags & URB_SETUP_MAP_SINGLE))
1427 		dma_unmap_single(hcd->self.sysdev,
1428 				urb->setup_dma,
1429 				sizeof(struct usb_ctrlrequest),
1430 				DMA_TO_DEVICE);
1431 	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1432 		hcd_free_coherent(urb->dev->bus,
1433 				&urb->setup_dma,
1434 				(void **) &urb->setup_packet,
1435 				sizeof(struct usb_ctrlrequest),
1436 				DMA_TO_DEVICE);
1437 
1438 	/* Make it safe to call this routine more than once */
1439 	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1440 }
1441 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1442 
1443 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1444 {
1445 	if (hcd->driver->unmap_urb_for_dma)
1446 		hcd->driver->unmap_urb_for_dma(hcd, urb);
1447 	else
1448 		usb_hcd_unmap_urb_for_dma(hcd, urb);
1449 }
1450 
1451 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1452 {
1453 	enum dma_data_direction dir;
1454 
1455 	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1456 
1457 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1458 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1459 	    (urb->transfer_flags & URB_DMA_MAP_SG))
1460 		dma_unmap_sg(hcd->self.sysdev,
1461 				urb->sg,
1462 				urb->num_sgs,
1463 				dir);
1464 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1465 		 (urb->transfer_flags & URB_DMA_MAP_PAGE))
1466 		dma_unmap_page(hcd->self.sysdev,
1467 				urb->transfer_dma,
1468 				urb->transfer_buffer_length,
1469 				dir);
1470 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1471 		 (urb->transfer_flags & URB_DMA_MAP_SINGLE))
1472 		dma_unmap_single(hcd->self.sysdev,
1473 				urb->transfer_dma,
1474 				urb->transfer_buffer_length,
1475 				dir);
1476 	else if (urb->transfer_flags & URB_MAP_LOCAL)
1477 		hcd_free_coherent(urb->dev->bus,
1478 				&urb->transfer_dma,
1479 				&urb->transfer_buffer,
1480 				urb->transfer_buffer_length,
1481 				dir);
1482 
1483 	/* Make it safe to call this routine more than once */
1484 	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1485 			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1486 }
1487 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1488 
1489 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1490 			   gfp_t mem_flags)
1491 {
1492 	if (hcd->driver->map_urb_for_dma)
1493 		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1494 	else
1495 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1496 }
1497 
1498 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1499 			    gfp_t mem_flags)
1500 {
1501 	enum dma_data_direction dir;
1502 	int ret = 0;
1503 
1504 	/* Map the URB's buffers for DMA access.
1505 	 * Lower level HCD code should use *_dma exclusively,
1506 	 * unless it uses pio or talks to another transport,
1507 	 * or uses the provided scatter gather list for bulk.
1508 	 */
1509 
1510 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1511 		if (hcd->self.uses_pio_for_control)
1512 			return ret;
1513 		if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) {
1514 			if (is_vmalloc_addr(urb->setup_packet)) {
1515 				WARN_ONCE(1, "setup packet is not dma capable\n");
1516 				return -EAGAIN;
1517 			} else if (object_is_on_stack(urb->setup_packet)) {
1518 				WARN_ONCE(1, "setup packet is on stack\n");
1519 				return -EAGAIN;
1520 			}
1521 
1522 			urb->setup_dma = dma_map_single(
1523 					hcd->self.sysdev,
1524 					urb->setup_packet,
1525 					sizeof(struct usb_ctrlrequest),
1526 					DMA_TO_DEVICE);
1527 			if (dma_mapping_error(hcd->self.sysdev,
1528 						urb->setup_dma))
1529 				return -EAGAIN;
1530 			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1531 		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1532 			ret = hcd_alloc_coherent(
1533 					urb->dev->bus, mem_flags,
1534 					&urb->setup_dma,
1535 					(void **)&urb->setup_packet,
1536 					sizeof(struct usb_ctrlrequest),
1537 					DMA_TO_DEVICE);
1538 			if (ret)
1539 				return ret;
1540 			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1541 		}
1542 	}
1543 
1544 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1545 	if (urb->transfer_buffer_length != 0
1546 	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1547 		if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) {
1548 			if (urb->num_sgs) {
1549 				int n;
1550 
1551 				/* We don't support sg for isoc transfers ! */
1552 				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1553 					WARN_ON(1);
1554 					return -EINVAL;
1555 				}
1556 
1557 				n = dma_map_sg(
1558 						hcd->self.sysdev,
1559 						urb->sg,
1560 						urb->num_sgs,
1561 						dir);
1562 				if (n <= 0)
1563 					ret = -EAGAIN;
1564 				else
1565 					urb->transfer_flags |= URB_DMA_MAP_SG;
1566 				urb->num_mapped_sgs = n;
1567 				if (n != urb->num_sgs)
1568 					urb->transfer_flags |=
1569 							URB_DMA_SG_COMBINED;
1570 			} else if (urb->sg) {
1571 				struct scatterlist *sg = urb->sg;
1572 				urb->transfer_dma = dma_map_page(
1573 						hcd->self.sysdev,
1574 						sg_page(sg),
1575 						sg->offset,
1576 						urb->transfer_buffer_length,
1577 						dir);
1578 				if (dma_mapping_error(hcd->self.sysdev,
1579 						urb->transfer_dma))
1580 					ret = -EAGAIN;
1581 				else
1582 					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1583 			} else if (is_vmalloc_addr(urb->transfer_buffer)) {
1584 				WARN_ONCE(1, "transfer buffer not dma capable\n");
1585 				ret = -EAGAIN;
1586 			} else if (object_is_on_stack(urb->transfer_buffer)) {
1587 				WARN_ONCE(1, "transfer buffer is on stack\n");
1588 				ret = -EAGAIN;
1589 			} else {
1590 				urb->transfer_dma = dma_map_single(
1591 						hcd->self.sysdev,
1592 						urb->transfer_buffer,
1593 						urb->transfer_buffer_length,
1594 						dir);
1595 				if (dma_mapping_error(hcd->self.sysdev,
1596 						urb->transfer_dma))
1597 					ret = -EAGAIN;
1598 				else
1599 					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1600 			}
1601 		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1602 			ret = hcd_alloc_coherent(
1603 					urb->dev->bus, mem_flags,
1604 					&urb->transfer_dma,
1605 					&urb->transfer_buffer,
1606 					urb->transfer_buffer_length,
1607 					dir);
1608 			if (ret == 0)
1609 				urb->transfer_flags |= URB_MAP_LOCAL;
1610 		}
1611 		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1612 				URB_SETUP_MAP_LOCAL)))
1613 			usb_hcd_unmap_urb_for_dma(hcd, urb);
1614 	}
1615 	return ret;
1616 }
1617 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1618 
1619 /*-------------------------------------------------------------------------*/
1620 
1621 /* may be called in any context with a valid urb->dev usecount
1622  * caller surrenders "ownership" of urb
1623  * expects usb_submit_urb() to have sanity checked and conditioned all
1624  * inputs in the urb
1625  */
1626 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1627 {
1628 	int			status;
1629 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1630 
1631 	/* increment urb's reference count as part of giving it to the HCD
1632 	 * (which will control it).  HCD guarantees that it either returns
1633 	 * an error or calls giveback(), but not both.
1634 	 */
1635 	usb_get_urb(urb);
1636 	atomic_inc(&urb->use_count);
1637 	atomic_inc(&urb->dev->urbnum);
1638 	usbmon_urb_submit(&hcd->self, urb);
1639 
1640 	/* NOTE requirements on root-hub callers (usbfs and the hub
1641 	 * driver, for now):  URBs' urb->transfer_buffer must be
1642 	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1643 	 * they could clobber root hub response data.  Also, control
1644 	 * URBs must be submitted in process context with interrupts
1645 	 * enabled.
1646 	 */
1647 
1648 	if (is_root_hub(urb->dev)) {
1649 		status = rh_urb_enqueue(hcd, urb);
1650 	} else {
1651 		status = map_urb_for_dma(hcd, urb, mem_flags);
1652 		if (likely(status == 0)) {
1653 			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1654 			if (unlikely(status))
1655 				unmap_urb_for_dma(hcd, urb);
1656 		}
1657 	}
1658 
1659 	if (unlikely(status)) {
1660 		usbmon_urb_submit_error(&hcd->self, urb, status);
1661 		urb->hcpriv = NULL;
1662 		INIT_LIST_HEAD(&urb->urb_list);
1663 		atomic_dec(&urb->use_count);
1664 		atomic_dec(&urb->dev->urbnum);
1665 		if (atomic_read(&urb->reject))
1666 			wake_up(&usb_kill_urb_queue);
1667 		usb_put_urb(urb);
1668 	}
1669 	return status;
1670 }
1671 
1672 /*-------------------------------------------------------------------------*/
1673 
1674 /* this makes the hcd giveback() the urb more quickly, by kicking it
1675  * off hardware queues (which may take a while) and returning it as
1676  * soon as practical.  we've already set up the urb's return status,
1677  * but we can't know if the callback completed already.
1678  */
1679 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1680 {
1681 	int		value;
1682 
1683 	if (is_root_hub(urb->dev))
1684 		value = usb_rh_urb_dequeue(hcd, urb, status);
1685 	else {
1686 
1687 		/* The only reason an HCD might fail this call is if
1688 		 * it has not yet fully queued the urb to begin with.
1689 		 * Such failures should be harmless. */
1690 		value = hcd->driver->urb_dequeue(hcd, urb, status);
1691 	}
1692 	return value;
1693 }
1694 
1695 /*
1696  * called in any context
1697  *
1698  * caller guarantees urb won't be recycled till both unlink()
1699  * and the urb's completion function return
1700  */
1701 int usb_hcd_unlink_urb (struct urb *urb, int status)
1702 {
1703 	struct usb_hcd		*hcd;
1704 	struct usb_device	*udev = urb->dev;
1705 	int			retval = -EIDRM;
1706 	unsigned long		flags;
1707 
1708 	/* Prevent the device and bus from going away while
1709 	 * the unlink is carried out.  If they are already gone
1710 	 * then urb->use_count must be 0, since disconnected
1711 	 * devices can't have any active URBs.
1712 	 */
1713 	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1714 	if (atomic_read(&urb->use_count) > 0) {
1715 		retval = 0;
1716 		usb_get_dev(udev);
1717 	}
1718 	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1719 	if (retval == 0) {
1720 		hcd = bus_to_hcd(urb->dev->bus);
1721 		retval = unlink1(hcd, urb, status);
1722 		if (retval == 0)
1723 			retval = -EINPROGRESS;
1724 		else if (retval != -EIDRM && retval != -EBUSY)
1725 			dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n",
1726 					urb, retval);
1727 		usb_put_dev(udev);
1728 	}
1729 	return retval;
1730 }
1731 
1732 /*-------------------------------------------------------------------------*/
1733 
1734 static void __usb_hcd_giveback_urb(struct urb *urb)
1735 {
1736 	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1737 	struct usb_anchor *anchor = urb->anchor;
1738 	int status = urb->unlinked;
1739 
1740 	urb->hcpriv = NULL;
1741 	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1742 	    urb->actual_length < urb->transfer_buffer_length &&
1743 	    !status))
1744 		status = -EREMOTEIO;
1745 
1746 	unmap_urb_for_dma(hcd, urb);
1747 	usbmon_urb_complete(&hcd->self, urb, status);
1748 	usb_anchor_suspend_wakeups(anchor);
1749 	usb_unanchor_urb(urb);
1750 	if (likely(status == 0))
1751 		usb_led_activity(USB_LED_EVENT_HOST);
1752 
1753 	/* pass ownership to the completion handler */
1754 	urb->status = status;
1755 	urb->complete(urb);
1756 
1757 	usb_anchor_resume_wakeups(anchor);
1758 	atomic_dec(&urb->use_count);
1759 	if (unlikely(atomic_read(&urb->reject)))
1760 		wake_up(&usb_kill_urb_queue);
1761 	usb_put_urb(urb);
1762 }
1763 
1764 static void usb_giveback_urb_bh(unsigned long param)
1765 {
1766 	struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param;
1767 	struct list_head local_list;
1768 
1769 	spin_lock_irq(&bh->lock);
1770 	bh->running = true;
1771  restart:
1772 	list_replace_init(&bh->head, &local_list);
1773 	spin_unlock_irq(&bh->lock);
1774 
1775 	while (!list_empty(&local_list)) {
1776 		struct urb *urb;
1777 
1778 		urb = list_entry(local_list.next, struct urb, urb_list);
1779 		list_del_init(&urb->urb_list);
1780 		bh->completing_ep = urb->ep;
1781 		__usb_hcd_giveback_urb(urb);
1782 		bh->completing_ep = NULL;
1783 	}
1784 
1785 	/* check if there are new URBs to giveback */
1786 	spin_lock_irq(&bh->lock);
1787 	if (!list_empty(&bh->head))
1788 		goto restart;
1789 	bh->running = false;
1790 	spin_unlock_irq(&bh->lock);
1791 }
1792 
1793 /**
1794  * usb_hcd_giveback_urb - return URB from HCD to device driver
1795  * @hcd: host controller returning the URB
1796  * @urb: urb being returned to the USB device driver.
1797  * @status: completion status code for the URB.
1798  * Context: in_interrupt()
1799  *
1800  * This hands the URB from HCD to its USB device driver, using its
1801  * completion function.  The HCD has freed all per-urb resources
1802  * (and is done using urb->hcpriv).  It also released all HCD locks;
1803  * the device driver won't cause problems if it frees, modifies,
1804  * or resubmits this URB.
1805  *
1806  * If @urb was unlinked, the value of @status will be overridden by
1807  * @urb->unlinked.  Erroneous short transfers are detected in case
1808  * the HCD hasn't checked for them.
1809  */
1810 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1811 {
1812 	struct giveback_urb_bh *bh;
1813 	bool running, high_prio_bh;
1814 
1815 	/* pass status to tasklet via unlinked */
1816 	if (likely(!urb->unlinked))
1817 		urb->unlinked = status;
1818 
1819 	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1820 		__usb_hcd_giveback_urb(urb);
1821 		return;
1822 	}
1823 
1824 	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
1825 		bh = &hcd->high_prio_bh;
1826 		high_prio_bh = true;
1827 	} else {
1828 		bh = &hcd->low_prio_bh;
1829 		high_prio_bh = false;
1830 	}
1831 
1832 	spin_lock(&bh->lock);
1833 	list_add_tail(&urb->urb_list, &bh->head);
1834 	running = bh->running;
1835 	spin_unlock(&bh->lock);
1836 
1837 	if (running)
1838 		;
1839 	else if (high_prio_bh)
1840 		tasklet_hi_schedule(&bh->bh);
1841 	else
1842 		tasklet_schedule(&bh->bh);
1843 }
1844 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1845 
1846 /*-------------------------------------------------------------------------*/
1847 
1848 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1849  * queue to drain completely.  The caller must first insure that no more
1850  * URBs can be submitted for this endpoint.
1851  */
1852 void usb_hcd_flush_endpoint(struct usb_device *udev,
1853 		struct usb_host_endpoint *ep)
1854 {
1855 	struct usb_hcd		*hcd;
1856 	struct urb		*urb;
1857 
1858 	if (!ep)
1859 		return;
1860 	might_sleep();
1861 	hcd = bus_to_hcd(udev->bus);
1862 
1863 	/* No more submits can occur */
1864 	spin_lock_irq(&hcd_urb_list_lock);
1865 rescan:
1866 	list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) {
1867 		int	is_in;
1868 
1869 		if (urb->unlinked)
1870 			continue;
1871 		usb_get_urb (urb);
1872 		is_in = usb_urb_dir_in(urb);
1873 		spin_unlock(&hcd_urb_list_lock);
1874 
1875 		/* kick hcd */
1876 		unlink1(hcd, urb, -ESHUTDOWN);
1877 		dev_dbg (hcd->self.controller,
1878 			"shutdown urb %pK ep%d%s%s\n",
1879 			urb, usb_endpoint_num(&ep->desc),
1880 			is_in ? "in" : "out",
1881 			({	char *s;
1882 
1883 				 switch (usb_endpoint_type(&ep->desc)) {
1884 				 case USB_ENDPOINT_XFER_CONTROL:
1885 					s = ""; break;
1886 				 case USB_ENDPOINT_XFER_BULK:
1887 					s = "-bulk"; break;
1888 				 case USB_ENDPOINT_XFER_INT:
1889 					s = "-intr"; break;
1890 				 default:
1891 					s = "-iso"; break;
1892 				};
1893 				s;
1894 			}));
1895 		usb_put_urb (urb);
1896 
1897 		/* list contents may have changed */
1898 		spin_lock(&hcd_urb_list_lock);
1899 		goto rescan;
1900 	}
1901 	spin_unlock_irq(&hcd_urb_list_lock);
1902 
1903 	/* Wait until the endpoint queue is completely empty */
1904 	while (!list_empty (&ep->urb_list)) {
1905 		spin_lock_irq(&hcd_urb_list_lock);
1906 
1907 		/* The list may have changed while we acquired the spinlock */
1908 		urb = NULL;
1909 		if (!list_empty (&ep->urb_list)) {
1910 			urb = list_entry (ep->urb_list.prev, struct urb,
1911 					urb_list);
1912 			usb_get_urb (urb);
1913 		}
1914 		spin_unlock_irq(&hcd_urb_list_lock);
1915 
1916 		if (urb) {
1917 			usb_kill_urb (urb);
1918 			usb_put_urb (urb);
1919 		}
1920 	}
1921 }
1922 
1923 /**
1924  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1925  *				the bus bandwidth
1926  * @udev: target &usb_device
1927  * @new_config: new configuration to install
1928  * @cur_alt: the current alternate interface setting
1929  * @new_alt: alternate interface setting that is being installed
1930  *
1931  * To change configurations, pass in the new configuration in new_config,
1932  * and pass NULL for cur_alt and new_alt.
1933  *
1934  * To reset a device's configuration (put the device in the ADDRESSED state),
1935  * pass in NULL for new_config, cur_alt, and new_alt.
1936  *
1937  * To change alternate interface settings, pass in NULL for new_config,
1938  * pass in the current alternate interface setting in cur_alt,
1939  * and pass in the new alternate interface setting in new_alt.
1940  *
1941  * Return: An error if the requested bandwidth change exceeds the
1942  * bus bandwidth or host controller internal resources.
1943  */
1944 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1945 		struct usb_host_config *new_config,
1946 		struct usb_host_interface *cur_alt,
1947 		struct usb_host_interface *new_alt)
1948 {
1949 	int num_intfs, i, j;
1950 	struct usb_host_interface *alt = NULL;
1951 	int ret = 0;
1952 	struct usb_hcd *hcd;
1953 	struct usb_host_endpoint *ep;
1954 
1955 	hcd = bus_to_hcd(udev->bus);
1956 	if (!hcd->driver->check_bandwidth)
1957 		return 0;
1958 
1959 	/* Configuration is being removed - set configuration 0 */
1960 	if (!new_config && !cur_alt) {
1961 		for (i = 1; i < 16; ++i) {
1962 			ep = udev->ep_out[i];
1963 			if (ep)
1964 				hcd->driver->drop_endpoint(hcd, udev, ep);
1965 			ep = udev->ep_in[i];
1966 			if (ep)
1967 				hcd->driver->drop_endpoint(hcd, udev, ep);
1968 		}
1969 		hcd->driver->check_bandwidth(hcd, udev);
1970 		return 0;
1971 	}
1972 	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1973 	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1974 	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1975 	 * ok to exclude it.
1976 	 */
1977 	if (new_config) {
1978 		num_intfs = new_config->desc.bNumInterfaces;
1979 		/* Remove endpoints (except endpoint 0, which is always on the
1980 		 * schedule) from the old config from the schedule
1981 		 */
1982 		for (i = 1; i < 16; ++i) {
1983 			ep = udev->ep_out[i];
1984 			if (ep) {
1985 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1986 				if (ret < 0)
1987 					goto reset;
1988 			}
1989 			ep = udev->ep_in[i];
1990 			if (ep) {
1991 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1992 				if (ret < 0)
1993 					goto reset;
1994 			}
1995 		}
1996 		for (i = 0; i < num_intfs; ++i) {
1997 			struct usb_host_interface *first_alt;
1998 			int iface_num;
1999 
2000 			first_alt = &new_config->intf_cache[i]->altsetting[0];
2001 			iface_num = first_alt->desc.bInterfaceNumber;
2002 			/* Set up endpoints for alternate interface setting 0 */
2003 			alt = usb_find_alt_setting(new_config, iface_num, 0);
2004 			if (!alt)
2005 				/* No alt setting 0? Pick the first setting. */
2006 				alt = first_alt;
2007 
2008 			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
2009 				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
2010 				if (ret < 0)
2011 					goto reset;
2012 			}
2013 		}
2014 	}
2015 	if (cur_alt && new_alt) {
2016 		struct usb_interface *iface = usb_ifnum_to_if(udev,
2017 				cur_alt->desc.bInterfaceNumber);
2018 
2019 		if (!iface)
2020 			return -EINVAL;
2021 		if (iface->resetting_device) {
2022 			/*
2023 			 * The USB core just reset the device, so the xHCI host
2024 			 * and the device will think alt setting 0 is installed.
2025 			 * However, the USB core will pass in the alternate
2026 			 * setting installed before the reset as cur_alt.  Dig
2027 			 * out the alternate setting 0 structure, or the first
2028 			 * alternate setting if a broken device doesn't have alt
2029 			 * setting 0.
2030 			 */
2031 			cur_alt = usb_altnum_to_altsetting(iface, 0);
2032 			if (!cur_alt)
2033 				cur_alt = &iface->altsetting[0];
2034 		}
2035 
2036 		/* Drop all the endpoints in the current alt setting */
2037 		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
2038 			ret = hcd->driver->drop_endpoint(hcd, udev,
2039 					&cur_alt->endpoint[i]);
2040 			if (ret < 0)
2041 				goto reset;
2042 		}
2043 		/* Add all the endpoints in the new alt setting */
2044 		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
2045 			ret = hcd->driver->add_endpoint(hcd, udev,
2046 					&new_alt->endpoint[i]);
2047 			if (ret < 0)
2048 				goto reset;
2049 		}
2050 	}
2051 	ret = hcd->driver->check_bandwidth(hcd, udev);
2052 reset:
2053 	if (ret < 0)
2054 		hcd->driver->reset_bandwidth(hcd, udev);
2055 	return ret;
2056 }
2057 
2058 /* Disables the endpoint: synchronizes with the hcd to make sure all
2059  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
2060  * have been called previously.  Use for set_configuration, set_interface,
2061  * driver removal, physical disconnect.
2062  *
2063  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
2064  * type, maxpacket size, toggle, halt status, and scheduling.
2065  */
2066 void usb_hcd_disable_endpoint(struct usb_device *udev,
2067 		struct usb_host_endpoint *ep)
2068 {
2069 	struct usb_hcd		*hcd;
2070 
2071 	might_sleep();
2072 	hcd = bus_to_hcd(udev->bus);
2073 	if (hcd->driver->endpoint_disable)
2074 		hcd->driver->endpoint_disable(hcd, ep);
2075 }
2076 
2077 /**
2078  * usb_hcd_reset_endpoint - reset host endpoint state
2079  * @udev: USB device.
2080  * @ep:   the endpoint to reset.
2081  *
2082  * Resets any host endpoint state such as the toggle bit, sequence
2083  * number and current window.
2084  */
2085 void usb_hcd_reset_endpoint(struct usb_device *udev,
2086 			    struct usb_host_endpoint *ep)
2087 {
2088 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2089 
2090 	if (hcd->driver->endpoint_reset)
2091 		hcd->driver->endpoint_reset(hcd, ep);
2092 	else {
2093 		int epnum = usb_endpoint_num(&ep->desc);
2094 		int is_out = usb_endpoint_dir_out(&ep->desc);
2095 		int is_control = usb_endpoint_xfer_control(&ep->desc);
2096 
2097 		usb_settoggle(udev, epnum, is_out, 0);
2098 		if (is_control)
2099 			usb_settoggle(udev, epnum, !is_out, 0);
2100 	}
2101 }
2102 
2103 /**
2104  * usb_alloc_streams - allocate bulk endpoint stream IDs.
2105  * @interface:		alternate setting that includes all endpoints.
2106  * @eps:		array of endpoints that need streams.
2107  * @num_eps:		number of endpoints in the array.
2108  * @num_streams:	number of streams to allocate.
2109  * @mem_flags:		flags hcd should use to allocate memory.
2110  *
2111  * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
2112  * Drivers may queue multiple transfers to different stream IDs, which may
2113  * complete in a different order than they were queued.
2114  *
2115  * Return: On success, the number of allocated streams. On failure, a negative
2116  * error code.
2117  */
2118 int usb_alloc_streams(struct usb_interface *interface,
2119 		struct usb_host_endpoint **eps, unsigned int num_eps,
2120 		unsigned int num_streams, gfp_t mem_flags)
2121 {
2122 	struct usb_hcd *hcd;
2123 	struct usb_device *dev;
2124 	int i, ret;
2125 
2126 	dev = interface_to_usbdev(interface);
2127 	hcd = bus_to_hcd(dev->bus);
2128 	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2129 		return -EINVAL;
2130 	if (dev->speed < USB_SPEED_SUPER)
2131 		return -EINVAL;
2132 	if (dev->state < USB_STATE_CONFIGURED)
2133 		return -ENODEV;
2134 
2135 	for (i = 0; i < num_eps; i++) {
2136 		/* Streams only apply to bulk endpoints. */
2137 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2138 			return -EINVAL;
2139 		/* Re-alloc is not allowed */
2140 		if (eps[i]->streams)
2141 			return -EINVAL;
2142 	}
2143 
2144 	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2145 			num_streams, mem_flags);
2146 	if (ret < 0)
2147 		return ret;
2148 
2149 	for (i = 0; i < num_eps; i++)
2150 		eps[i]->streams = ret;
2151 
2152 	return ret;
2153 }
2154 EXPORT_SYMBOL_GPL(usb_alloc_streams);
2155 
2156 /**
2157  * usb_free_streams - free bulk endpoint stream IDs.
2158  * @interface:	alternate setting that includes all endpoints.
2159  * @eps:	array of endpoints to remove streams from.
2160  * @num_eps:	number of endpoints in the array.
2161  * @mem_flags:	flags hcd should use to allocate memory.
2162  *
2163  * Reverts a group of bulk endpoints back to not using stream IDs.
2164  * Can fail if we are given bad arguments, or HCD is broken.
2165  *
2166  * Return: 0 on success. On failure, a negative error code.
2167  */
2168 int usb_free_streams(struct usb_interface *interface,
2169 		struct usb_host_endpoint **eps, unsigned int num_eps,
2170 		gfp_t mem_flags)
2171 {
2172 	struct usb_hcd *hcd;
2173 	struct usb_device *dev;
2174 	int i, ret;
2175 
2176 	dev = interface_to_usbdev(interface);
2177 	hcd = bus_to_hcd(dev->bus);
2178 	if (dev->speed < USB_SPEED_SUPER)
2179 		return -EINVAL;
2180 
2181 	/* Double-free is not allowed */
2182 	for (i = 0; i < num_eps; i++)
2183 		if (!eps[i] || !eps[i]->streams)
2184 			return -EINVAL;
2185 
2186 	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2187 	if (ret < 0)
2188 		return ret;
2189 
2190 	for (i = 0; i < num_eps; i++)
2191 		eps[i]->streams = 0;
2192 
2193 	return ret;
2194 }
2195 EXPORT_SYMBOL_GPL(usb_free_streams);
2196 
2197 /* Protect against drivers that try to unlink URBs after the device
2198  * is gone, by waiting until all unlinks for @udev are finished.
2199  * Since we don't currently track URBs by device, simply wait until
2200  * nothing is running in the locked region of usb_hcd_unlink_urb().
2201  */
2202 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2203 {
2204 	spin_lock_irq(&hcd_urb_unlink_lock);
2205 	spin_unlock_irq(&hcd_urb_unlink_lock);
2206 }
2207 
2208 /*-------------------------------------------------------------------------*/
2209 
2210 /* called in any context */
2211 int usb_hcd_get_frame_number (struct usb_device *udev)
2212 {
2213 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
2214 
2215 	if (!HCD_RH_RUNNING(hcd))
2216 		return -ESHUTDOWN;
2217 	return hcd->driver->get_frame_number (hcd);
2218 }
2219 
2220 /*-------------------------------------------------------------------------*/
2221 
2222 #ifdef	CONFIG_PM
2223 
2224 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2225 {
2226 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2227 	int		status;
2228 	int		old_state = hcd->state;
2229 
2230 	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2231 			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2232 			rhdev->do_remote_wakeup);
2233 	if (HCD_DEAD(hcd)) {
2234 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2235 		return 0;
2236 	}
2237 
2238 	if (!hcd->driver->bus_suspend) {
2239 		status = -ENOENT;
2240 	} else {
2241 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2242 		hcd->state = HC_STATE_QUIESCING;
2243 		status = hcd->driver->bus_suspend(hcd);
2244 	}
2245 	if (status == 0) {
2246 		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2247 		hcd->state = HC_STATE_SUSPENDED;
2248 
2249 		if (!PMSG_IS_AUTO(msg))
2250 			usb_phy_roothub_suspend(hcd->self.sysdev,
2251 						hcd->phy_roothub);
2252 
2253 		/* Did we race with a root-hub wakeup event? */
2254 		if (rhdev->do_remote_wakeup) {
2255 			char	buffer[6];
2256 
2257 			status = hcd->driver->hub_status_data(hcd, buffer);
2258 			if (status != 0) {
2259 				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2260 				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2261 				status = -EBUSY;
2262 			}
2263 		}
2264 	} else {
2265 		spin_lock_irq(&hcd_root_hub_lock);
2266 		if (!HCD_DEAD(hcd)) {
2267 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2268 			hcd->state = old_state;
2269 		}
2270 		spin_unlock_irq(&hcd_root_hub_lock);
2271 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2272 				"suspend", status);
2273 	}
2274 	return status;
2275 }
2276 
2277 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2278 {
2279 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2280 	int		status;
2281 	int		old_state = hcd->state;
2282 
2283 	dev_dbg(&rhdev->dev, "usb %sresume\n",
2284 			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2285 	if (HCD_DEAD(hcd)) {
2286 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2287 		return 0;
2288 	}
2289 
2290 	if (!PMSG_IS_AUTO(msg)) {
2291 		status = usb_phy_roothub_resume(hcd->self.sysdev,
2292 						hcd->phy_roothub);
2293 		if (status)
2294 			return status;
2295 	}
2296 
2297 	if (!hcd->driver->bus_resume)
2298 		return -ENOENT;
2299 	if (HCD_RH_RUNNING(hcd))
2300 		return 0;
2301 
2302 	hcd->state = HC_STATE_RESUMING;
2303 	status = hcd->driver->bus_resume(hcd);
2304 	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2305 	if (status == 0) {
2306 		struct usb_device *udev;
2307 		int port1;
2308 
2309 		spin_lock_irq(&hcd_root_hub_lock);
2310 		if (!HCD_DEAD(hcd)) {
2311 			usb_set_device_state(rhdev, rhdev->actconfig
2312 					? USB_STATE_CONFIGURED
2313 					: USB_STATE_ADDRESS);
2314 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2315 			hcd->state = HC_STATE_RUNNING;
2316 		}
2317 		spin_unlock_irq(&hcd_root_hub_lock);
2318 
2319 		/*
2320 		 * Check whether any of the enabled ports on the root hub are
2321 		 * unsuspended.  If they are then a TRSMRCY delay is needed
2322 		 * (this is what the USB-2 spec calls a "global resume").
2323 		 * Otherwise we can skip the delay.
2324 		 */
2325 		usb_hub_for_each_child(rhdev, port1, udev) {
2326 			if (udev->state != USB_STATE_NOTATTACHED &&
2327 					!udev->port_is_suspended) {
2328 				usleep_range(10000, 11000);	/* TRSMRCY */
2329 				break;
2330 			}
2331 		}
2332 	} else {
2333 		hcd->state = old_state;
2334 		usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub);
2335 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2336 				"resume", status);
2337 		if (status != -ESHUTDOWN)
2338 			usb_hc_died(hcd);
2339 	}
2340 	return status;
2341 }
2342 
2343 /* Workqueue routine for root-hub remote wakeup */
2344 static void hcd_resume_work(struct work_struct *work)
2345 {
2346 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2347 	struct usb_device *udev = hcd->self.root_hub;
2348 
2349 	usb_remote_wakeup(udev);
2350 }
2351 
2352 /**
2353  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2354  * @hcd: host controller for this root hub
2355  *
2356  * The USB host controller calls this function when its root hub is
2357  * suspended (with the remote wakeup feature enabled) and a remote
2358  * wakeup request is received.  The routine submits a workqueue request
2359  * to resume the root hub (that is, manage its downstream ports again).
2360  */
2361 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2362 {
2363 	unsigned long flags;
2364 
2365 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2366 	if (hcd->rh_registered) {
2367 		pm_wakeup_event(&hcd->self.root_hub->dev, 0);
2368 		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2369 		queue_work(pm_wq, &hcd->wakeup_work);
2370 	}
2371 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2372 }
2373 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2374 
2375 #endif	/* CONFIG_PM */
2376 
2377 /*-------------------------------------------------------------------------*/
2378 
2379 #ifdef	CONFIG_USB_OTG
2380 
2381 /**
2382  * usb_bus_start_enum - start immediate enumeration (for OTG)
2383  * @bus: the bus (must use hcd framework)
2384  * @port_num: 1-based number of port; usually bus->otg_port
2385  * Context: in_interrupt()
2386  *
2387  * Starts enumeration, with an immediate reset followed later by
2388  * hub_wq identifying and possibly configuring the device.
2389  * This is needed by OTG controller drivers, where it helps meet
2390  * HNP protocol timing requirements for starting a port reset.
2391  *
2392  * Return: 0 if successful.
2393  */
2394 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2395 {
2396 	struct usb_hcd		*hcd;
2397 	int			status = -EOPNOTSUPP;
2398 
2399 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2400 	 * boards with root hubs hooked up to internal devices (instead of
2401 	 * just the OTG port) may need more attention to resetting...
2402 	 */
2403 	hcd = bus_to_hcd(bus);
2404 	if (port_num && hcd->driver->start_port_reset)
2405 		status = hcd->driver->start_port_reset(hcd, port_num);
2406 
2407 	/* allocate hub_wq shortly after (first) root port reset finishes;
2408 	 * it may issue others, until at least 50 msecs have passed.
2409 	 */
2410 	if (status == 0)
2411 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2412 	return status;
2413 }
2414 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2415 
2416 #endif
2417 
2418 /*-------------------------------------------------------------------------*/
2419 
2420 /**
2421  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2422  * @irq: the IRQ being raised
2423  * @__hcd: pointer to the HCD whose IRQ is being signaled
2424  *
2425  * If the controller isn't HALTed, calls the driver's irq handler.
2426  * Checks whether the controller is now dead.
2427  *
2428  * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2429  */
2430 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2431 {
2432 	struct usb_hcd		*hcd = __hcd;
2433 	irqreturn_t		rc;
2434 
2435 	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2436 		rc = IRQ_NONE;
2437 	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2438 		rc = IRQ_NONE;
2439 	else
2440 		rc = IRQ_HANDLED;
2441 
2442 	return rc;
2443 }
2444 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2445 
2446 /*-------------------------------------------------------------------------*/
2447 
2448 /**
2449  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2450  * @hcd: pointer to the HCD representing the controller
2451  *
2452  * This is called by bus glue to report a USB host controller that died
2453  * while operations may still have been pending.  It's called automatically
2454  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2455  *
2456  * Only call this function with the primary HCD.
2457  */
2458 void usb_hc_died (struct usb_hcd *hcd)
2459 {
2460 	unsigned long flags;
2461 
2462 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2463 
2464 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2465 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2466 	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2467 	if (hcd->rh_registered) {
2468 		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2469 
2470 		/* make hub_wq clean up old urbs and devices */
2471 		usb_set_device_state (hcd->self.root_hub,
2472 				USB_STATE_NOTATTACHED);
2473 		usb_kick_hub_wq(hcd->self.root_hub);
2474 	}
2475 	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2476 		hcd = hcd->shared_hcd;
2477 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2478 		set_bit(HCD_FLAG_DEAD, &hcd->flags);
2479 		if (hcd->rh_registered) {
2480 			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2481 
2482 			/* make hub_wq clean up old urbs and devices */
2483 			usb_set_device_state(hcd->self.root_hub,
2484 					USB_STATE_NOTATTACHED);
2485 			usb_kick_hub_wq(hcd->self.root_hub);
2486 		}
2487 	}
2488 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2489 	/* Make sure that the other roothub is also deallocated. */
2490 }
2491 EXPORT_SYMBOL_GPL (usb_hc_died);
2492 
2493 /*-------------------------------------------------------------------------*/
2494 
2495 static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2496 {
2497 
2498 	spin_lock_init(&bh->lock);
2499 	INIT_LIST_HEAD(&bh->head);
2500 	tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh);
2501 }
2502 
2503 struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
2504 		struct device *sysdev, struct device *dev, const char *bus_name,
2505 		struct usb_hcd *primary_hcd)
2506 {
2507 	struct usb_hcd *hcd;
2508 
2509 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2510 	if (!hcd)
2511 		return NULL;
2512 	if (primary_hcd == NULL) {
2513 		hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex),
2514 				GFP_KERNEL);
2515 		if (!hcd->address0_mutex) {
2516 			kfree(hcd);
2517 			dev_dbg(dev, "hcd address0 mutex alloc failed\n");
2518 			return NULL;
2519 		}
2520 		mutex_init(hcd->address0_mutex);
2521 		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2522 				GFP_KERNEL);
2523 		if (!hcd->bandwidth_mutex) {
2524 			kfree(hcd->address0_mutex);
2525 			kfree(hcd);
2526 			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2527 			return NULL;
2528 		}
2529 		mutex_init(hcd->bandwidth_mutex);
2530 		dev_set_drvdata(dev, hcd);
2531 	} else {
2532 		mutex_lock(&usb_port_peer_mutex);
2533 		hcd->address0_mutex = primary_hcd->address0_mutex;
2534 		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2535 		hcd->primary_hcd = primary_hcd;
2536 		primary_hcd->primary_hcd = primary_hcd;
2537 		hcd->shared_hcd = primary_hcd;
2538 		primary_hcd->shared_hcd = hcd;
2539 		mutex_unlock(&usb_port_peer_mutex);
2540 	}
2541 
2542 	kref_init(&hcd->kref);
2543 
2544 	usb_bus_init(&hcd->self);
2545 	hcd->self.controller = dev;
2546 	hcd->self.sysdev = sysdev;
2547 	hcd->self.bus_name = bus_name;
2548 	hcd->self.uses_dma = (sysdev->dma_mask != NULL);
2549 
2550 	timer_setup(&hcd->rh_timer, rh_timer_func, 0);
2551 #ifdef CONFIG_PM
2552 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2553 #endif
2554 
2555 	hcd->driver = driver;
2556 	hcd->speed = driver->flags & HCD_MASK;
2557 	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2558 			"USB Host Controller";
2559 	return hcd;
2560 }
2561 EXPORT_SYMBOL_GPL(__usb_create_hcd);
2562 
2563 /**
2564  * usb_create_shared_hcd - create and initialize an HCD structure
2565  * @driver: HC driver that will use this hcd
2566  * @dev: device for this HC, stored in hcd->self.controller
2567  * @bus_name: value to store in hcd->self.bus_name
2568  * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2569  *              PCI device.  Only allocate certain resources for the primary HCD
2570  * Context: !in_interrupt()
2571  *
2572  * Allocate a struct usb_hcd, with extra space at the end for the
2573  * HC driver's private data.  Initialize the generic members of the
2574  * hcd structure.
2575  *
2576  * Return: On success, a pointer to the created and initialized HCD structure.
2577  * On failure (e.g. if memory is unavailable), %NULL.
2578  */
2579 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2580 		struct device *dev, const char *bus_name,
2581 		struct usb_hcd *primary_hcd)
2582 {
2583 	return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd);
2584 }
2585 EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2586 
2587 /**
2588  * usb_create_hcd - create and initialize an HCD structure
2589  * @driver: HC driver that will use this hcd
2590  * @dev: device for this HC, stored in hcd->self.controller
2591  * @bus_name: value to store in hcd->self.bus_name
2592  * Context: !in_interrupt()
2593  *
2594  * Allocate a struct usb_hcd, with extra space at the end for the
2595  * HC driver's private data.  Initialize the generic members of the
2596  * hcd structure.
2597  *
2598  * Return: On success, a pointer to the created and initialized HCD
2599  * structure. On failure (e.g. if memory is unavailable), %NULL.
2600  */
2601 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2602 		struct device *dev, const char *bus_name)
2603 {
2604 	return __usb_create_hcd(driver, dev, dev, bus_name, NULL);
2605 }
2606 EXPORT_SYMBOL_GPL(usb_create_hcd);
2607 
2608 /*
2609  * Roothubs that share one PCI device must also share the bandwidth mutex.
2610  * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2611  * deallocated.
2612  *
2613  * Make sure to deallocate the bandwidth_mutex only when the last HCD is
2614  * freed.  When hcd_release() is called for either hcd in a peer set,
2615  * invalidate the peer's ->shared_hcd and ->primary_hcd pointers.
2616  */
2617 static void hcd_release(struct kref *kref)
2618 {
2619 	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2620 
2621 	mutex_lock(&usb_port_peer_mutex);
2622 	if (hcd->shared_hcd) {
2623 		struct usb_hcd *peer = hcd->shared_hcd;
2624 
2625 		peer->shared_hcd = NULL;
2626 		peer->primary_hcd = NULL;
2627 	} else {
2628 		kfree(hcd->address0_mutex);
2629 		kfree(hcd->bandwidth_mutex);
2630 	}
2631 	mutex_unlock(&usb_port_peer_mutex);
2632 	kfree(hcd);
2633 }
2634 
2635 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2636 {
2637 	if (hcd)
2638 		kref_get (&hcd->kref);
2639 	return hcd;
2640 }
2641 EXPORT_SYMBOL_GPL(usb_get_hcd);
2642 
2643 void usb_put_hcd (struct usb_hcd *hcd)
2644 {
2645 	if (hcd)
2646 		kref_put (&hcd->kref, hcd_release);
2647 }
2648 EXPORT_SYMBOL_GPL(usb_put_hcd);
2649 
2650 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2651 {
2652 	if (!hcd->primary_hcd)
2653 		return 1;
2654 	return hcd == hcd->primary_hcd;
2655 }
2656 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2657 
2658 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2659 {
2660 	if (!hcd->driver->find_raw_port_number)
2661 		return port1;
2662 
2663 	return hcd->driver->find_raw_port_number(hcd, port1);
2664 }
2665 
2666 static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2667 		unsigned int irqnum, unsigned long irqflags)
2668 {
2669 	int retval;
2670 
2671 	if (hcd->driver->irq) {
2672 
2673 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2674 				hcd->driver->description, hcd->self.busnum);
2675 		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2676 				hcd->irq_descr, hcd);
2677 		if (retval != 0) {
2678 			dev_err(hcd->self.controller,
2679 					"request interrupt %d failed\n",
2680 					irqnum);
2681 			return retval;
2682 		}
2683 		hcd->irq = irqnum;
2684 		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2685 				(hcd->driver->flags & HCD_MEMORY) ?
2686 					"io mem" : "io base",
2687 					(unsigned long long)hcd->rsrc_start);
2688 	} else {
2689 		hcd->irq = 0;
2690 		if (hcd->rsrc_start)
2691 			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2692 					(hcd->driver->flags & HCD_MEMORY) ?
2693 					"io mem" : "io base",
2694 					(unsigned long long)hcd->rsrc_start);
2695 	}
2696 	return 0;
2697 }
2698 
2699 /*
2700  * Before we free this root hub, flush in-flight peering attempts
2701  * and disable peer lookups
2702  */
2703 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2704 {
2705 	struct usb_device *rhdev;
2706 
2707 	mutex_lock(&usb_port_peer_mutex);
2708 	rhdev = hcd->self.root_hub;
2709 	hcd->self.root_hub = NULL;
2710 	mutex_unlock(&usb_port_peer_mutex);
2711 	usb_put_dev(rhdev);
2712 }
2713 
2714 /**
2715  * usb_add_hcd - finish generic HCD structure initialization and register
2716  * @hcd: the usb_hcd structure to initialize
2717  * @irqnum: Interrupt line to allocate
2718  * @irqflags: Interrupt type flags
2719  *
2720  * Finish the remaining parts of generic HCD initialization: allocate the
2721  * buffers of consistent memory, register the bus, request the IRQ line,
2722  * and call the driver's reset() and start() routines.
2723  */
2724 int usb_add_hcd(struct usb_hcd *hcd,
2725 		unsigned int irqnum, unsigned long irqflags)
2726 {
2727 	int retval;
2728 	struct usb_device *rhdev;
2729 
2730 	if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) {
2731 		hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev);
2732 		if (IS_ERR(hcd->phy_roothub))
2733 			return PTR_ERR(hcd->phy_roothub);
2734 
2735 		retval = usb_phy_roothub_init(hcd->phy_roothub);
2736 		if (retval)
2737 			return retval;
2738 
2739 		retval = usb_phy_roothub_power_on(hcd->phy_roothub);
2740 		if (retval)
2741 			goto err_usb_phy_roothub_power_on;
2742 	}
2743 
2744 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2745 
2746 	/* Keep old behaviour if authorized_default is not in [0, 1]. */
2747 	if (authorized_default < 0 || authorized_default > 1) {
2748 		if (hcd->wireless)
2749 			clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2750 		else
2751 			set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2752 	} else {
2753 		if (authorized_default)
2754 			set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2755 		else
2756 			clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2757 	}
2758 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2759 
2760 	/* per default all interfaces are authorized */
2761 	set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
2762 
2763 	/* HC is in reset state, but accessible.  Now do the one-time init,
2764 	 * bottom up so that hcds can customize the root hubs before hub_wq
2765 	 * starts talking to them.  (Note, bus id is assigned early too.)
2766 	 */
2767 	retval = hcd_buffer_create(hcd);
2768 	if (retval != 0) {
2769 		dev_dbg(hcd->self.sysdev, "pool alloc failed\n");
2770 		goto err_create_buf;
2771 	}
2772 
2773 	retval = usb_register_bus(&hcd->self);
2774 	if (retval < 0)
2775 		goto err_register_bus;
2776 
2777 	rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2778 	if (rhdev == NULL) {
2779 		dev_err(hcd->self.sysdev, "unable to allocate root hub\n");
2780 		retval = -ENOMEM;
2781 		goto err_allocate_root_hub;
2782 	}
2783 	mutex_lock(&usb_port_peer_mutex);
2784 	hcd->self.root_hub = rhdev;
2785 	mutex_unlock(&usb_port_peer_mutex);
2786 
2787 	rhdev->rx_lanes = 1;
2788 	rhdev->tx_lanes = 1;
2789 
2790 	switch (hcd->speed) {
2791 	case HCD_USB11:
2792 		rhdev->speed = USB_SPEED_FULL;
2793 		break;
2794 	case HCD_USB2:
2795 		rhdev->speed = USB_SPEED_HIGH;
2796 		break;
2797 	case HCD_USB25:
2798 		rhdev->speed = USB_SPEED_WIRELESS;
2799 		break;
2800 	case HCD_USB3:
2801 		rhdev->speed = USB_SPEED_SUPER;
2802 		break;
2803 	case HCD_USB32:
2804 		rhdev->rx_lanes = 2;
2805 		rhdev->tx_lanes = 2;
2806 		/* fall through */
2807 	case HCD_USB31:
2808 		rhdev->speed = USB_SPEED_SUPER_PLUS;
2809 		break;
2810 	default:
2811 		retval = -EINVAL;
2812 		goto err_set_rh_speed;
2813 	}
2814 
2815 	/* wakeup flag init defaults to "everything works" for root hubs,
2816 	 * but drivers can override it in reset() if needed, along with
2817 	 * recording the overall controller's system wakeup capability.
2818 	 */
2819 	device_set_wakeup_capable(&rhdev->dev, 1);
2820 
2821 	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2822 	 * registered.  But since the controller can die at any time,
2823 	 * let's initialize the flag before touching the hardware.
2824 	 */
2825 	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2826 
2827 	/* "reset" is misnamed; its role is now one-time init. the controller
2828 	 * should already have been reset (and boot firmware kicked off etc).
2829 	 */
2830 	if (hcd->driver->reset) {
2831 		retval = hcd->driver->reset(hcd);
2832 		if (retval < 0) {
2833 			dev_err(hcd->self.controller, "can't setup: %d\n",
2834 					retval);
2835 			goto err_hcd_driver_setup;
2836 		}
2837 	}
2838 	hcd->rh_pollable = 1;
2839 
2840 	/* NOTE: root hub and controller capabilities may not be the same */
2841 	if (device_can_wakeup(hcd->self.controller)
2842 			&& device_can_wakeup(&hcd->self.root_hub->dev))
2843 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2844 
2845 	/* initialize tasklets */
2846 	init_giveback_urb_bh(&hcd->high_prio_bh);
2847 	init_giveback_urb_bh(&hcd->low_prio_bh);
2848 
2849 	/* enable irqs just before we start the controller,
2850 	 * if the BIOS provides legacy PCI irqs.
2851 	 */
2852 	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2853 		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2854 		if (retval)
2855 			goto err_request_irq;
2856 	}
2857 
2858 	hcd->state = HC_STATE_RUNNING;
2859 	retval = hcd->driver->start(hcd);
2860 	if (retval < 0) {
2861 		dev_err(hcd->self.controller, "startup error %d\n", retval);
2862 		goto err_hcd_driver_start;
2863 	}
2864 
2865 	/* starting here, usbcore will pay attention to this root hub */
2866 	retval = register_root_hub(hcd);
2867 	if (retval != 0)
2868 		goto err_register_root_hub;
2869 
2870 	retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2871 	if (retval < 0) {
2872 		printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n",
2873 		       retval);
2874 		goto error_create_attr_group;
2875 	}
2876 	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2877 		usb_hcd_poll_rh_status(hcd);
2878 
2879 	return retval;
2880 
2881 error_create_attr_group:
2882 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2883 	if (HC_IS_RUNNING(hcd->state))
2884 		hcd->state = HC_STATE_QUIESCING;
2885 	spin_lock_irq(&hcd_root_hub_lock);
2886 	hcd->rh_registered = 0;
2887 	spin_unlock_irq(&hcd_root_hub_lock);
2888 
2889 #ifdef CONFIG_PM
2890 	cancel_work_sync(&hcd->wakeup_work);
2891 #endif
2892 	mutex_lock(&usb_bus_idr_lock);
2893 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2894 	mutex_unlock(&usb_bus_idr_lock);
2895 err_register_root_hub:
2896 	hcd->rh_pollable = 0;
2897 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2898 	del_timer_sync(&hcd->rh_timer);
2899 	hcd->driver->stop(hcd);
2900 	hcd->state = HC_STATE_HALT;
2901 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2902 	del_timer_sync(&hcd->rh_timer);
2903 err_hcd_driver_start:
2904 	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2905 		free_irq(irqnum, hcd);
2906 err_request_irq:
2907 err_hcd_driver_setup:
2908 err_set_rh_speed:
2909 	usb_put_invalidate_rhdev(hcd);
2910 err_allocate_root_hub:
2911 	usb_deregister_bus(&hcd->self);
2912 err_register_bus:
2913 	hcd_buffer_destroy(hcd);
2914 err_create_buf:
2915 	usb_phy_roothub_power_off(hcd->phy_roothub);
2916 err_usb_phy_roothub_power_on:
2917 	usb_phy_roothub_exit(hcd->phy_roothub);
2918 
2919 	return retval;
2920 }
2921 EXPORT_SYMBOL_GPL(usb_add_hcd);
2922 
2923 /**
2924  * usb_remove_hcd - shutdown processing for generic HCDs
2925  * @hcd: the usb_hcd structure to remove
2926  * Context: !in_interrupt()
2927  *
2928  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2929  * invoking the HCD's stop() method.
2930  */
2931 void usb_remove_hcd(struct usb_hcd *hcd)
2932 {
2933 	struct usb_device *rhdev = hcd->self.root_hub;
2934 
2935 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2936 
2937 	usb_get_dev(rhdev);
2938 	sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2939 
2940 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2941 	if (HC_IS_RUNNING (hcd->state))
2942 		hcd->state = HC_STATE_QUIESCING;
2943 
2944 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2945 	spin_lock_irq (&hcd_root_hub_lock);
2946 	hcd->rh_registered = 0;
2947 	spin_unlock_irq (&hcd_root_hub_lock);
2948 
2949 #ifdef CONFIG_PM
2950 	cancel_work_sync(&hcd->wakeup_work);
2951 #endif
2952 
2953 	mutex_lock(&usb_bus_idr_lock);
2954 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2955 	mutex_unlock(&usb_bus_idr_lock);
2956 
2957 	/*
2958 	 * tasklet_kill() isn't needed here because:
2959 	 * - driver's disconnect() called from usb_disconnect() should
2960 	 *   make sure its URBs are completed during the disconnect()
2961 	 *   callback
2962 	 *
2963 	 * - it is too late to run complete() here since driver may have
2964 	 *   been removed already now
2965 	 */
2966 
2967 	/* Prevent any more root-hub status calls from the timer.
2968 	 * The HCD might still restart the timer (if a port status change
2969 	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
2970 	 * the hub_status_data() callback.
2971 	 */
2972 	hcd->rh_pollable = 0;
2973 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2974 	del_timer_sync(&hcd->rh_timer);
2975 
2976 	hcd->driver->stop(hcd);
2977 	hcd->state = HC_STATE_HALT;
2978 
2979 	/* In case the HCD restarted the timer, stop it again. */
2980 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2981 	del_timer_sync(&hcd->rh_timer);
2982 
2983 	if (usb_hcd_is_primary_hcd(hcd)) {
2984 		if (hcd->irq > 0)
2985 			free_irq(hcd->irq, hcd);
2986 	}
2987 
2988 	usb_deregister_bus(&hcd->self);
2989 	hcd_buffer_destroy(hcd);
2990 
2991 	usb_phy_roothub_power_off(hcd->phy_roothub);
2992 	usb_phy_roothub_exit(hcd->phy_roothub);
2993 
2994 	usb_put_invalidate_rhdev(hcd);
2995 	hcd->flags = 0;
2996 }
2997 EXPORT_SYMBOL_GPL(usb_remove_hcd);
2998 
2999 void
3000 usb_hcd_platform_shutdown(struct platform_device *dev)
3001 {
3002 	struct usb_hcd *hcd = platform_get_drvdata(dev);
3003 
3004 	if (hcd->driver->shutdown)
3005 		hcd->driver->shutdown(hcd);
3006 }
3007 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
3008 
3009 /*-------------------------------------------------------------------------*/
3010 
3011 #if IS_ENABLED(CONFIG_USB_MON)
3012 
3013 const struct usb_mon_operations *mon_ops;
3014 
3015 /*
3016  * The registration is unlocked.
3017  * We do it this way because we do not want to lock in hot paths.
3018  *
3019  * Notice that the code is minimally error-proof. Because usbmon needs
3020  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
3021  */
3022 
3023 int usb_mon_register(const struct usb_mon_operations *ops)
3024 {
3025 
3026 	if (mon_ops)
3027 		return -EBUSY;
3028 
3029 	mon_ops = ops;
3030 	mb();
3031 	return 0;
3032 }
3033 EXPORT_SYMBOL_GPL (usb_mon_register);
3034 
3035 void usb_mon_deregister (void)
3036 {
3037 
3038 	if (mon_ops == NULL) {
3039 		printk(KERN_ERR "USB: monitor was not registered\n");
3040 		return;
3041 	}
3042 	mon_ops = NULL;
3043 	mb();
3044 }
3045 EXPORT_SYMBOL_GPL (usb_mon_deregister);
3046 
3047 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
3048