xref: /openbmc/linux/drivers/usb/core/hcd.c (revision 82b5d164)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright Linus Torvalds 1999
4  * (C) Copyright Johannes Erdfelt 1999-2001
5  * (C) Copyright Andreas Gal 1999
6  * (C) Copyright Gregory P. Smith 1999
7  * (C) Copyright Deti Fliegl 1999
8  * (C) Copyright Randy Dunlap 2000
9  * (C) Copyright David Brownell 2000-2002
10  */
11 
12 #include <linux/bcd.h>
13 #include <linux/module.h>
14 #include <linux/version.h>
15 #include <linux/kernel.h>
16 #include <linux/sched/task_stack.h>
17 #include <linux/slab.h>
18 #include <linux/completion.h>
19 #include <linux/utsname.h>
20 #include <linux/mm.h>
21 #include <asm/io.h>
22 #include <linux/device.h>
23 #include <linux/dma-mapping.h>
24 #include <linux/mutex.h>
25 #include <asm/irq.h>
26 #include <asm/byteorder.h>
27 #include <asm/unaligned.h>
28 #include <linux/platform_device.h>
29 #include <linux/workqueue.h>
30 #include <linux/pm_runtime.h>
31 #include <linux/types.h>
32 #include <linux/genalloc.h>
33 #include <linux/io.h>
34 
35 #include <linux/phy/phy.h>
36 #include <linux/usb.h>
37 #include <linux/usb/hcd.h>
38 #include <linux/usb/otg.h>
39 
40 #include "usb.h"
41 #include "phy.h"
42 
43 
44 /*-------------------------------------------------------------------------*/
45 
46 /*
47  * USB Host Controller Driver framework
48  *
49  * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
50  * HCD-specific behaviors/bugs.
51  *
52  * This does error checks, tracks devices and urbs, and delegates to a
53  * "hc_driver" only for code (and data) that really needs to know about
54  * hardware differences.  That includes root hub registers, i/o queues,
55  * and so on ... but as little else as possible.
56  *
57  * Shared code includes most of the "root hub" code (these are emulated,
58  * though each HC's hardware works differently) and PCI glue, plus request
59  * tracking overhead.  The HCD code should only block on spinlocks or on
60  * hardware handshaking; blocking on software events (such as other kernel
61  * threads releasing resources, or completing actions) is all generic.
62  *
63  * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
64  * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
65  * only by the hub driver ... and that neither should be seen or used by
66  * usb client device drivers.
67  *
68  * Contributors of ideas or unattributed patches include: David Brownell,
69  * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
70  *
71  * HISTORY:
72  * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
73  *		associated cleanup.  "usb_hcd" still != "usb_bus".
74  * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
75  */
76 
77 /*-------------------------------------------------------------------------*/
78 
79 /* Keep track of which host controller drivers are loaded */
80 unsigned long usb_hcds_loaded;
81 EXPORT_SYMBOL_GPL(usb_hcds_loaded);
82 
83 /* host controllers we manage */
84 DEFINE_IDR (usb_bus_idr);
85 EXPORT_SYMBOL_GPL (usb_bus_idr);
86 
87 /* used when allocating bus numbers */
88 #define USB_MAXBUS		64
89 
90 /* used when updating list of hcds */
91 DEFINE_MUTEX(usb_bus_idr_lock);	/* exported only for usbfs */
92 EXPORT_SYMBOL_GPL (usb_bus_idr_lock);
93 
94 /* used for controlling access to virtual root hubs */
95 static DEFINE_SPINLOCK(hcd_root_hub_lock);
96 
97 /* used when updating an endpoint's URB list */
98 static DEFINE_SPINLOCK(hcd_urb_list_lock);
99 
100 /* used to protect against unlinking URBs after the device is gone */
101 static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
102 
103 /* wait queue for synchronous unlinks */
104 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
105 
106 /*-------------------------------------------------------------------------*/
107 
108 /*
109  * Sharable chunks of root hub code.
110  */
111 
112 /*-------------------------------------------------------------------------*/
113 #define KERNEL_REL	bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff))
114 #define KERNEL_VER	bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff))
115 
116 /* usb 3.1 root hub device descriptor */
117 static const u8 usb31_rh_dev_descriptor[18] = {
118 	0x12,       /*  __u8  bLength; */
119 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
120 	0x10, 0x03, /*  __le16 bcdUSB; v3.1 */
121 
122 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
123 	0x00,	    /*  __u8  bDeviceSubClass; */
124 	0x03,       /*  __u8  bDeviceProtocol; USB 3 hub */
125 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
126 
127 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
128 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
129 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
130 
131 	0x03,       /*  __u8  iManufacturer; */
132 	0x02,       /*  __u8  iProduct; */
133 	0x01,       /*  __u8  iSerialNumber; */
134 	0x01        /*  __u8  bNumConfigurations; */
135 };
136 
137 /* usb 3.0 root hub device descriptor */
138 static const u8 usb3_rh_dev_descriptor[18] = {
139 	0x12,       /*  __u8  bLength; */
140 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
141 	0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
142 
143 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
144 	0x00,	    /*  __u8  bDeviceSubClass; */
145 	0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
146 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
147 
148 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
149 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
150 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
151 
152 	0x03,       /*  __u8  iManufacturer; */
153 	0x02,       /*  __u8  iProduct; */
154 	0x01,       /*  __u8  iSerialNumber; */
155 	0x01        /*  __u8  bNumConfigurations; */
156 };
157 
158 /* usb 2.5 (wireless USB 1.0) root hub device descriptor */
159 static const u8 usb25_rh_dev_descriptor[18] = {
160 	0x12,       /*  __u8  bLength; */
161 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
162 	0x50, 0x02, /*  __le16 bcdUSB; v2.5 */
163 
164 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
165 	0x00,	    /*  __u8  bDeviceSubClass; */
166 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
167 	0xFF,       /*  __u8  bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */
168 
169 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
170 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
171 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
172 
173 	0x03,       /*  __u8  iManufacturer; */
174 	0x02,       /*  __u8  iProduct; */
175 	0x01,       /*  __u8  iSerialNumber; */
176 	0x01        /*  __u8  bNumConfigurations; */
177 };
178 
179 /* usb 2.0 root hub device descriptor */
180 static const u8 usb2_rh_dev_descriptor[18] = {
181 	0x12,       /*  __u8  bLength; */
182 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
183 	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
184 
185 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
186 	0x00,	    /*  __u8  bDeviceSubClass; */
187 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
188 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
189 
190 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
191 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
192 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
193 
194 	0x03,       /*  __u8  iManufacturer; */
195 	0x02,       /*  __u8  iProduct; */
196 	0x01,       /*  __u8  iSerialNumber; */
197 	0x01        /*  __u8  bNumConfigurations; */
198 };
199 
200 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
201 
202 /* usb 1.1 root hub device descriptor */
203 static const u8 usb11_rh_dev_descriptor[18] = {
204 	0x12,       /*  __u8  bLength; */
205 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
206 	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
207 
208 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
209 	0x00,	    /*  __u8  bDeviceSubClass; */
210 	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
211 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
212 
213 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
214 	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
215 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
216 
217 	0x03,       /*  __u8  iManufacturer; */
218 	0x02,       /*  __u8  iProduct; */
219 	0x01,       /*  __u8  iSerialNumber; */
220 	0x01        /*  __u8  bNumConfigurations; */
221 };
222 
223 
224 /*-------------------------------------------------------------------------*/
225 
226 /* Configuration descriptors for our root hubs */
227 
228 static const u8 fs_rh_config_descriptor[] = {
229 
230 	/* one configuration */
231 	0x09,       /*  __u8  bLength; */
232 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
233 	0x19, 0x00, /*  __le16 wTotalLength; */
234 	0x01,       /*  __u8  bNumInterfaces; (1) */
235 	0x01,       /*  __u8  bConfigurationValue; */
236 	0x00,       /*  __u8  iConfiguration; */
237 	0xc0,       /*  __u8  bmAttributes;
238 				 Bit 7: must be set,
239 				     6: Self-powered,
240 				     5: Remote wakeup,
241 				     4..0: resvd */
242 	0x00,       /*  __u8  MaxPower; */
243 
244 	/* USB 1.1:
245 	 * USB 2.0, single TT organization (mandatory):
246 	 *	one interface, protocol 0
247 	 *
248 	 * USB 2.0, multiple TT organization (optional):
249 	 *	two interfaces, protocols 1 (like single TT)
250 	 *	and 2 (multiple TT mode) ... config is
251 	 *	sometimes settable
252 	 *	NOT IMPLEMENTED
253 	 */
254 
255 	/* one interface */
256 	0x09,       /*  __u8  if_bLength; */
257 	USB_DT_INTERFACE,  /* __u8 if_bDescriptorType; Interface */
258 	0x00,       /*  __u8  if_bInterfaceNumber; */
259 	0x00,       /*  __u8  if_bAlternateSetting; */
260 	0x01,       /*  __u8  if_bNumEndpoints; */
261 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
262 	0x00,       /*  __u8  if_bInterfaceSubClass; */
263 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
264 	0x00,       /*  __u8  if_iInterface; */
265 
266 	/* one endpoint (status change endpoint) */
267 	0x07,       /*  __u8  ep_bLength; */
268 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
269 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
270 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
271 	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
272 	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
273 };
274 
275 static const u8 hs_rh_config_descriptor[] = {
276 
277 	/* one configuration */
278 	0x09,       /*  __u8  bLength; */
279 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
280 	0x19, 0x00, /*  __le16 wTotalLength; */
281 	0x01,       /*  __u8  bNumInterfaces; (1) */
282 	0x01,       /*  __u8  bConfigurationValue; */
283 	0x00,       /*  __u8  iConfiguration; */
284 	0xc0,       /*  __u8  bmAttributes;
285 				 Bit 7: must be set,
286 				     6: Self-powered,
287 				     5: Remote wakeup,
288 				     4..0: resvd */
289 	0x00,       /*  __u8  MaxPower; */
290 
291 	/* USB 1.1:
292 	 * USB 2.0, single TT organization (mandatory):
293 	 *	one interface, protocol 0
294 	 *
295 	 * USB 2.0, multiple TT organization (optional):
296 	 *	two interfaces, protocols 1 (like single TT)
297 	 *	and 2 (multiple TT mode) ... config is
298 	 *	sometimes settable
299 	 *	NOT IMPLEMENTED
300 	 */
301 
302 	/* one interface */
303 	0x09,       /*  __u8  if_bLength; */
304 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
305 	0x00,       /*  __u8  if_bInterfaceNumber; */
306 	0x00,       /*  __u8  if_bAlternateSetting; */
307 	0x01,       /*  __u8  if_bNumEndpoints; */
308 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
309 	0x00,       /*  __u8  if_bInterfaceSubClass; */
310 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
311 	0x00,       /*  __u8  if_iInterface; */
312 
313 	/* one endpoint (status change endpoint) */
314 	0x07,       /*  __u8  ep_bLength; */
315 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
316 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
317 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
318 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
319 		     * see hub.c:hub_configure() for details. */
320 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
321 	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
322 };
323 
324 static const u8 ss_rh_config_descriptor[] = {
325 	/* one configuration */
326 	0x09,       /*  __u8  bLength; */
327 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
328 	0x1f, 0x00, /*  __le16 wTotalLength; */
329 	0x01,       /*  __u8  bNumInterfaces; (1) */
330 	0x01,       /*  __u8  bConfigurationValue; */
331 	0x00,       /*  __u8  iConfiguration; */
332 	0xc0,       /*  __u8  bmAttributes;
333 				 Bit 7: must be set,
334 				     6: Self-powered,
335 				     5: Remote wakeup,
336 				     4..0: resvd */
337 	0x00,       /*  __u8  MaxPower; */
338 
339 	/* one interface */
340 	0x09,       /*  __u8  if_bLength; */
341 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
342 	0x00,       /*  __u8  if_bInterfaceNumber; */
343 	0x00,       /*  __u8  if_bAlternateSetting; */
344 	0x01,       /*  __u8  if_bNumEndpoints; */
345 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
346 	0x00,       /*  __u8  if_bInterfaceSubClass; */
347 	0x00,       /*  __u8  if_bInterfaceProtocol; */
348 	0x00,       /*  __u8  if_iInterface; */
349 
350 	/* one endpoint (status change endpoint) */
351 	0x07,       /*  __u8  ep_bLength; */
352 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
353 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
354 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
355 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
356 		     * see hub.c:hub_configure() for details. */
357 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
358 	0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
359 
360 	/* one SuperSpeed endpoint companion descriptor */
361 	0x06,        /* __u8 ss_bLength */
362 	USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */
363 		     /* Companion */
364 	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
365 	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
366 	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
367 };
368 
369 /* authorized_default behaviour:
370  * -1 is authorized for all devices except wireless (old behaviour)
371  * 0 is unauthorized for all devices
372  * 1 is authorized for all devices
373  * 2 is authorized for internal devices
374  */
375 #define USB_AUTHORIZE_WIRED	-1
376 #define USB_AUTHORIZE_NONE	0
377 #define USB_AUTHORIZE_ALL	1
378 #define USB_AUTHORIZE_INTERNAL	2
379 
380 static int authorized_default = USB_AUTHORIZE_WIRED;
381 module_param(authorized_default, int, S_IRUGO|S_IWUSR);
382 MODULE_PARM_DESC(authorized_default,
383 		"Default USB device authorization: 0 is not authorized, 1 is "
384 		"authorized, 2 is authorized for internal devices, -1 is "
385 		"authorized except for wireless USB (default, old behaviour)");
386 /*-------------------------------------------------------------------------*/
387 
388 /**
389  * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
390  * @s: Null-terminated ASCII (actually ISO-8859-1) string
391  * @buf: Buffer for USB string descriptor (header + UTF-16LE)
392  * @len: Length (in bytes; may be odd) of descriptor buffer.
393  *
394  * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
395  * whichever is less.
396  *
397  * Note:
398  * USB String descriptors can contain at most 126 characters; input
399  * strings longer than that are truncated.
400  */
401 static unsigned
402 ascii2desc(char const *s, u8 *buf, unsigned len)
403 {
404 	unsigned n, t = 2 + 2*strlen(s);
405 
406 	if (t > 254)
407 		t = 254;	/* Longest possible UTF string descriptor */
408 	if (len > t)
409 		len = t;
410 
411 	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
412 
413 	n = len;
414 	while (n--) {
415 		*buf++ = t;
416 		if (!n--)
417 			break;
418 		*buf++ = t >> 8;
419 		t = (unsigned char)*s++;
420 	}
421 	return len;
422 }
423 
424 /**
425  * rh_string() - provides string descriptors for root hub
426  * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
427  * @hcd: the host controller for this root hub
428  * @data: buffer for output packet
429  * @len: length of the provided buffer
430  *
431  * Produces either a manufacturer, product or serial number string for the
432  * virtual root hub device.
433  *
434  * Return: The number of bytes filled in: the length of the descriptor or
435  * of the provided buffer, whichever is less.
436  */
437 static unsigned
438 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
439 {
440 	char buf[100];
441 	char const *s;
442 	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
443 
444 	/* language ids */
445 	switch (id) {
446 	case 0:
447 		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
448 		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
449 		if (len > 4)
450 			len = 4;
451 		memcpy(data, langids, len);
452 		return len;
453 	case 1:
454 		/* Serial number */
455 		s = hcd->self.bus_name;
456 		break;
457 	case 2:
458 		/* Product name */
459 		s = hcd->product_desc;
460 		break;
461 	case 3:
462 		/* Manufacturer */
463 		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
464 			init_utsname()->release, hcd->driver->description);
465 		s = buf;
466 		break;
467 	default:
468 		/* Can't happen; caller guarantees it */
469 		return 0;
470 	}
471 
472 	return ascii2desc(s, data, len);
473 }
474 
475 
476 /* Root hub control transfers execute synchronously */
477 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
478 {
479 	struct usb_ctrlrequest *cmd;
480 	u16		typeReq, wValue, wIndex, wLength;
481 	u8		*ubuf = urb->transfer_buffer;
482 	unsigned	len = 0;
483 	int		status;
484 	u8		patch_wakeup = 0;
485 	u8		patch_protocol = 0;
486 	u16		tbuf_size;
487 	u8		*tbuf = NULL;
488 	const u8	*bufp;
489 
490 	might_sleep();
491 
492 	spin_lock_irq(&hcd_root_hub_lock);
493 	status = usb_hcd_link_urb_to_ep(hcd, urb);
494 	spin_unlock_irq(&hcd_root_hub_lock);
495 	if (status)
496 		return status;
497 	urb->hcpriv = hcd;	/* Indicate it's queued */
498 
499 	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
500 	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
501 	wValue   = le16_to_cpu (cmd->wValue);
502 	wIndex   = le16_to_cpu (cmd->wIndex);
503 	wLength  = le16_to_cpu (cmd->wLength);
504 
505 	if (wLength > urb->transfer_buffer_length)
506 		goto error;
507 
508 	/*
509 	 * tbuf should be at least as big as the
510 	 * USB hub descriptor.
511 	 */
512 	tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
513 	tbuf = kzalloc(tbuf_size, GFP_KERNEL);
514 	if (!tbuf) {
515 		status = -ENOMEM;
516 		goto err_alloc;
517 	}
518 
519 	bufp = tbuf;
520 
521 
522 	urb->actual_length = 0;
523 	switch (typeReq) {
524 
525 	/* DEVICE REQUESTS */
526 
527 	/* The root hub's remote wakeup enable bit is implemented using
528 	 * driver model wakeup flags.  If this system supports wakeup
529 	 * through USB, userspace may change the default "allow wakeup"
530 	 * policy through sysfs or these calls.
531 	 *
532 	 * Most root hubs support wakeup from downstream devices, for
533 	 * runtime power management (disabling USB clocks and reducing
534 	 * VBUS power usage).  However, not all of them do so; silicon,
535 	 * board, and BIOS bugs here are not uncommon, so these can't
536 	 * be treated quite like external hubs.
537 	 *
538 	 * Likewise, not all root hubs will pass wakeup events upstream,
539 	 * to wake up the whole system.  So don't assume root hub and
540 	 * controller capabilities are identical.
541 	 */
542 
543 	case DeviceRequest | USB_REQ_GET_STATUS:
544 		tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
545 					<< USB_DEVICE_REMOTE_WAKEUP)
546 				| (1 << USB_DEVICE_SELF_POWERED);
547 		tbuf[1] = 0;
548 		len = 2;
549 		break;
550 	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
551 		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
552 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
553 		else
554 			goto error;
555 		break;
556 	case DeviceOutRequest | USB_REQ_SET_FEATURE:
557 		if (device_can_wakeup(&hcd->self.root_hub->dev)
558 				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
559 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
560 		else
561 			goto error;
562 		break;
563 	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
564 		tbuf[0] = 1;
565 		len = 1;
566 			/* FALLTHROUGH */
567 	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
568 		break;
569 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
570 		switch (wValue & 0xff00) {
571 		case USB_DT_DEVICE << 8:
572 			switch (hcd->speed) {
573 			case HCD_USB32:
574 			case HCD_USB31:
575 				bufp = usb31_rh_dev_descriptor;
576 				break;
577 			case HCD_USB3:
578 				bufp = usb3_rh_dev_descriptor;
579 				break;
580 			case HCD_USB25:
581 				bufp = usb25_rh_dev_descriptor;
582 				break;
583 			case HCD_USB2:
584 				bufp = usb2_rh_dev_descriptor;
585 				break;
586 			case HCD_USB11:
587 				bufp = usb11_rh_dev_descriptor;
588 				break;
589 			default:
590 				goto error;
591 			}
592 			len = 18;
593 			if (hcd->has_tt)
594 				patch_protocol = 1;
595 			break;
596 		case USB_DT_CONFIG << 8:
597 			switch (hcd->speed) {
598 			case HCD_USB32:
599 			case HCD_USB31:
600 			case HCD_USB3:
601 				bufp = ss_rh_config_descriptor;
602 				len = sizeof ss_rh_config_descriptor;
603 				break;
604 			case HCD_USB25:
605 			case HCD_USB2:
606 				bufp = hs_rh_config_descriptor;
607 				len = sizeof hs_rh_config_descriptor;
608 				break;
609 			case HCD_USB11:
610 				bufp = fs_rh_config_descriptor;
611 				len = sizeof fs_rh_config_descriptor;
612 				break;
613 			default:
614 				goto error;
615 			}
616 			if (device_can_wakeup(&hcd->self.root_hub->dev))
617 				patch_wakeup = 1;
618 			break;
619 		case USB_DT_STRING << 8:
620 			if ((wValue & 0xff) < 4)
621 				urb->actual_length = rh_string(wValue & 0xff,
622 						hcd, ubuf, wLength);
623 			else /* unsupported IDs --> "protocol stall" */
624 				goto error;
625 			break;
626 		case USB_DT_BOS << 8:
627 			goto nongeneric;
628 		default:
629 			goto error;
630 		}
631 		break;
632 	case DeviceRequest | USB_REQ_GET_INTERFACE:
633 		tbuf[0] = 0;
634 		len = 1;
635 			/* FALLTHROUGH */
636 	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
637 		break;
638 	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
639 		/* wValue == urb->dev->devaddr */
640 		dev_dbg (hcd->self.controller, "root hub device address %d\n",
641 			wValue);
642 		break;
643 
644 	/* INTERFACE REQUESTS (no defined feature/status flags) */
645 
646 	/* ENDPOINT REQUESTS */
647 
648 	case EndpointRequest | USB_REQ_GET_STATUS:
649 		/* ENDPOINT_HALT flag */
650 		tbuf[0] = 0;
651 		tbuf[1] = 0;
652 		len = 2;
653 			/* FALLTHROUGH */
654 	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
655 	case EndpointOutRequest | USB_REQ_SET_FEATURE:
656 		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
657 		break;
658 
659 	/* CLASS REQUESTS (and errors) */
660 
661 	default:
662 nongeneric:
663 		/* non-generic request */
664 		switch (typeReq) {
665 		case GetHubStatus:
666 			len = 4;
667 			break;
668 		case GetPortStatus:
669 			if (wValue == HUB_PORT_STATUS)
670 				len = 4;
671 			else
672 				/* other port status types return 8 bytes */
673 				len = 8;
674 			break;
675 		case GetHubDescriptor:
676 			len = sizeof (struct usb_hub_descriptor);
677 			break;
678 		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
679 			/* len is returned by hub_control */
680 			break;
681 		}
682 		status = hcd->driver->hub_control (hcd,
683 			typeReq, wValue, wIndex,
684 			tbuf, wLength);
685 
686 		if (typeReq == GetHubDescriptor)
687 			usb_hub_adjust_deviceremovable(hcd->self.root_hub,
688 				(struct usb_hub_descriptor *)tbuf);
689 		break;
690 error:
691 		/* "protocol stall" on error */
692 		status = -EPIPE;
693 	}
694 
695 	if (status < 0) {
696 		len = 0;
697 		if (status != -EPIPE) {
698 			dev_dbg (hcd->self.controller,
699 				"CTRL: TypeReq=0x%x val=0x%x "
700 				"idx=0x%x len=%d ==> %d\n",
701 				typeReq, wValue, wIndex,
702 				wLength, status);
703 		}
704 	} else if (status > 0) {
705 		/* hub_control may return the length of data copied. */
706 		len = status;
707 		status = 0;
708 	}
709 	if (len) {
710 		if (urb->transfer_buffer_length < len)
711 			len = urb->transfer_buffer_length;
712 		urb->actual_length = len;
713 		/* always USB_DIR_IN, toward host */
714 		memcpy (ubuf, bufp, len);
715 
716 		/* report whether RH hardware supports remote wakeup */
717 		if (patch_wakeup &&
718 				len > offsetof (struct usb_config_descriptor,
719 						bmAttributes))
720 			((struct usb_config_descriptor *)ubuf)->bmAttributes
721 				|= USB_CONFIG_ATT_WAKEUP;
722 
723 		/* report whether RH hardware has an integrated TT */
724 		if (patch_protocol &&
725 				len > offsetof(struct usb_device_descriptor,
726 						bDeviceProtocol))
727 			((struct usb_device_descriptor *) ubuf)->
728 				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
729 	}
730 
731 	kfree(tbuf);
732  err_alloc:
733 
734 	/* any errors get returned through the urb completion */
735 	spin_lock_irq(&hcd_root_hub_lock);
736 	usb_hcd_unlink_urb_from_ep(hcd, urb);
737 	usb_hcd_giveback_urb(hcd, urb, status);
738 	spin_unlock_irq(&hcd_root_hub_lock);
739 	return 0;
740 }
741 
742 /*-------------------------------------------------------------------------*/
743 
744 /*
745  * Root Hub interrupt transfers are polled using a timer if the
746  * driver requests it; otherwise the driver is responsible for
747  * calling usb_hcd_poll_rh_status() when an event occurs.
748  *
749  * Completions are called in_interrupt(), but they may or may not
750  * be in_irq().
751  */
752 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
753 {
754 	struct urb	*urb;
755 	int		length;
756 	unsigned long	flags;
757 	char		buffer[6];	/* Any root hubs with > 31 ports? */
758 
759 	if (unlikely(!hcd->rh_pollable))
760 		return;
761 	if (!hcd->uses_new_polling && !hcd->status_urb)
762 		return;
763 
764 	length = hcd->driver->hub_status_data(hcd, buffer);
765 	if (length > 0) {
766 
767 		/* try to complete the status urb */
768 		spin_lock_irqsave(&hcd_root_hub_lock, flags);
769 		urb = hcd->status_urb;
770 		if (urb) {
771 			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
772 			hcd->status_urb = NULL;
773 			urb->actual_length = length;
774 			memcpy(urb->transfer_buffer, buffer, length);
775 
776 			usb_hcd_unlink_urb_from_ep(hcd, urb);
777 			usb_hcd_giveback_urb(hcd, urb, 0);
778 		} else {
779 			length = 0;
780 			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
781 		}
782 		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
783 	}
784 
785 	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
786 	 * exceed that limit if HZ is 100. The math is more clunky than
787 	 * maybe expected, this is to make sure that all timers for USB devices
788 	 * fire at the same time to give the CPU a break in between */
789 	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
790 			(length == 0 && hcd->status_urb != NULL))
791 		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
792 }
793 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
794 
795 /* timer callback */
796 static void rh_timer_func (struct timer_list *t)
797 {
798 	struct usb_hcd *_hcd = from_timer(_hcd, t, rh_timer);
799 
800 	usb_hcd_poll_rh_status(_hcd);
801 }
802 
803 /*-------------------------------------------------------------------------*/
804 
805 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
806 {
807 	int		retval;
808 	unsigned long	flags;
809 	unsigned	len = 1 + (urb->dev->maxchild / 8);
810 
811 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
812 	if (hcd->status_urb || urb->transfer_buffer_length < len) {
813 		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
814 		retval = -EINVAL;
815 		goto done;
816 	}
817 
818 	retval = usb_hcd_link_urb_to_ep(hcd, urb);
819 	if (retval)
820 		goto done;
821 
822 	hcd->status_urb = urb;
823 	urb->hcpriv = hcd;	/* indicate it's queued */
824 	if (!hcd->uses_new_polling)
825 		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
826 
827 	/* If a status change has already occurred, report it ASAP */
828 	else if (HCD_POLL_PENDING(hcd))
829 		mod_timer(&hcd->rh_timer, jiffies);
830 	retval = 0;
831  done:
832 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
833 	return retval;
834 }
835 
836 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
837 {
838 	if (usb_endpoint_xfer_int(&urb->ep->desc))
839 		return rh_queue_status (hcd, urb);
840 	if (usb_endpoint_xfer_control(&urb->ep->desc))
841 		return rh_call_control (hcd, urb);
842 	return -EINVAL;
843 }
844 
845 /*-------------------------------------------------------------------------*/
846 
847 /* Unlinks of root-hub control URBs are legal, but they don't do anything
848  * since these URBs always execute synchronously.
849  */
850 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
851 {
852 	unsigned long	flags;
853 	int		rc;
854 
855 	spin_lock_irqsave(&hcd_root_hub_lock, flags);
856 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
857 	if (rc)
858 		goto done;
859 
860 	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
861 		;	/* Do nothing */
862 
863 	} else {				/* Status URB */
864 		if (!hcd->uses_new_polling)
865 			del_timer (&hcd->rh_timer);
866 		if (urb == hcd->status_urb) {
867 			hcd->status_urb = NULL;
868 			usb_hcd_unlink_urb_from_ep(hcd, urb);
869 			usb_hcd_giveback_urb(hcd, urb, status);
870 		}
871 	}
872  done:
873 	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
874 	return rc;
875 }
876 
877 
878 /*-------------------------------------------------------------------------*/
879 
880 /**
881  * usb_bus_init - shared initialization code
882  * @bus: the bus structure being initialized
883  *
884  * This code is used to initialize a usb_bus structure, memory for which is
885  * separately managed.
886  */
887 static void usb_bus_init (struct usb_bus *bus)
888 {
889 	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
890 
891 	bus->devnum_next = 1;
892 
893 	bus->root_hub = NULL;
894 	bus->busnum = -1;
895 	bus->bandwidth_allocated = 0;
896 	bus->bandwidth_int_reqs  = 0;
897 	bus->bandwidth_isoc_reqs = 0;
898 	mutex_init(&bus->devnum_next_mutex);
899 }
900 
901 /*-------------------------------------------------------------------------*/
902 
903 /**
904  * usb_register_bus - registers the USB host controller with the usb core
905  * @bus: pointer to the bus to register
906  * Context: !in_interrupt()
907  *
908  * Assigns a bus number, and links the controller into usbcore data
909  * structures so that it can be seen by scanning the bus list.
910  *
911  * Return: 0 if successful. A negative error code otherwise.
912  */
913 static int usb_register_bus(struct usb_bus *bus)
914 {
915 	int result = -E2BIG;
916 	int busnum;
917 
918 	mutex_lock(&usb_bus_idr_lock);
919 	busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL);
920 	if (busnum < 0) {
921 		pr_err("%s: failed to get bus number\n", usbcore_name);
922 		goto error_find_busnum;
923 	}
924 	bus->busnum = busnum;
925 	mutex_unlock(&usb_bus_idr_lock);
926 
927 	usb_notify_add_bus(bus);
928 
929 	dev_info (bus->controller, "new USB bus registered, assigned bus "
930 		  "number %d\n", bus->busnum);
931 	return 0;
932 
933 error_find_busnum:
934 	mutex_unlock(&usb_bus_idr_lock);
935 	return result;
936 }
937 
938 /**
939  * usb_deregister_bus - deregisters the USB host controller
940  * @bus: pointer to the bus to deregister
941  * Context: !in_interrupt()
942  *
943  * Recycles the bus number, and unlinks the controller from usbcore data
944  * structures so that it won't be seen by scanning the bus list.
945  */
946 static void usb_deregister_bus (struct usb_bus *bus)
947 {
948 	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
949 
950 	/*
951 	 * NOTE: make sure that all the devices are removed by the
952 	 * controller code, as well as having it call this when cleaning
953 	 * itself up
954 	 */
955 	mutex_lock(&usb_bus_idr_lock);
956 	idr_remove(&usb_bus_idr, bus->busnum);
957 	mutex_unlock(&usb_bus_idr_lock);
958 
959 	usb_notify_remove_bus(bus);
960 }
961 
962 /**
963  * register_root_hub - called by usb_add_hcd() to register a root hub
964  * @hcd: host controller for this root hub
965  *
966  * This function registers the root hub with the USB subsystem.  It sets up
967  * the device properly in the device tree and then calls usb_new_device()
968  * to register the usb device.  It also assigns the root hub's USB address
969  * (always 1).
970  *
971  * Return: 0 if successful. A negative error code otherwise.
972  */
973 static int register_root_hub(struct usb_hcd *hcd)
974 {
975 	struct device *parent_dev = hcd->self.controller;
976 	struct usb_device *usb_dev = hcd->self.root_hub;
977 	const int devnum = 1;
978 	int retval;
979 
980 	usb_dev->devnum = devnum;
981 	usb_dev->bus->devnum_next = devnum + 1;
982 	set_bit (devnum, usb_dev->bus->devmap.devicemap);
983 	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
984 
985 	mutex_lock(&usb_bus_idr_lock);
986 
987 	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
988 	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
989 	if (retval != sizeof usb_dev->descriptor) {
990 		mutex_unlock(&usb_bus_idr_lock);
991 		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
992 				dev_name(&usb_dev->dev), retval);
993 		return (retval < 0) ? retval : -EMSGSIZE;
994 	}
995 
996 	if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
997 		retval = usb_get_bos_descriptor(usb_dev);
998 		if (!retval) {
999 			usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
1000 		} else if (usb_dev->speed >= USB_SPEED_SUPER) {
1001 			mutex_unlock(&usb_bus_idr_lock);
1002 			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1003 					dev_name(&usb_dev->dev), retval);
1004 			return retval;
1005 		}
1006 	}
1007 
1008 	retval = usb_new_device (usb_dev);
1009 	if (retval) {
1010 		dev_err (parent_dev, "can't register root hub for %s, %d\n",
1011 				dev_name(&usb_dev->dev), retval);
1012 	} else {
1013 		spin_lock_irq (&hcd_root_hub_lock);
1014 		hcd->rh_registered = 1;
1015 		spin_unlock_irq (&hcd_root_hub_lock);
1016 
1017 		/* Did the HC die before the root hub was registered? */
1018 		if (HCD_DEAD(hcd))
1019 			usb_hc_died (hcd);	/* This time clean up */
1020 	}
1021 	mutex_unlock(&usb_bus_idr_lock);
1022 
1023 	return retval;
1024 }
1025 
1026 /*
1027  * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1028  * @bus: the bus which the root hub belongs to
1029  * @portnum: the port which is being resumed
1030  *
1031  * HCDs should call this function when they know that a resume signal is
1032  * being sent to a root-hub port.  The root hub will be prevented from
1033  * going into autosuspend until usb_hcd_end_port_resume() is called.
1034  *
1035  * The bus's private lock must be held by the caller.
1036  */
1037 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1038 {
1039 	unsigned bit = 1 << portnum;
1040 
1041 	if (!(bus->resuming_ports & bit)) {
1042 		bus->resuming_ports |= bit;
1043 		pm_runtime_get_noresume(&bus->root_hub->dev);
1044 	}
1045 }
1046 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1047 
1048 /*
1049  * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1050  * @bus: the bus which the root hub belongs to
1051  * @portnum: the port which is being resumed
1052  *
1053  * HCDs should call this function when they know that a resume signal has
1054  * stopped being sent to a root-hub port.  The root hub will be allowed to
1055  * autosuspend again.
1056  *
1057  * The bus's private lock must be held by the caller.
1058  */
1059 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1060 {
1061 	unsigned bit = 1 << portnum;
1062 
1063 	if (bus->resuming_ports & bit) {
1064 		bus->resuming_ports &= ~bit;
1065 		pm_runtime_put_noidle(&bus->root_hub->dev);
1066 	}
1067 }
1068 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1069 
1070 /*-------------------------------------------------------------------------*/
1071 
1072 /**
1073  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1074  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1075  * @is_input: true iff the transaction sends data to the host
1076  * @isoc: true for isochronous transactions, false for interrupt ones
1077  * @bytecount: how many bytes in the transaction.
1078  *
1079  * Return: Approximate bus time in nanoseconds for a periodic transaction.
1080  *
1081  * Note:
1082  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1083  * scheduled in software, this function is only used for such scheduling.
1084  */
1085 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1086 {
1087 	unsigned long	tmp;
1088 
1089 	switch (speed) {
1090 	case USB_SPEED_LOW: 	/* INTR only */
1091 		if (is_input) {
1092 			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1093 			return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1094 		} else {
1095 			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1096 			return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1097 		}
1098 	case USB_SPEED_FULL:	/* ISOC or INTR */
1099 		if (isoc) {
1100 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1101 			return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1102 		} else {
1103 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1104 			return 9107L + BW_HOST_DELAY + tmp;
1105 		}
1106 	case USB_SPEED_HIGH:	/* ISOC or INTR */
1107 		/* FIXME adjust for input vs output */
1108 		if (isoc)
1109 			tmp = HS_NSECS_ISO (bytecount);
1110 		else
1111 			tmp = HS_NSECS (bytecount);
1112 		return tmp;
1113 	default:
1114 		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1115 		return -1;
1116 	}
1117 }
1118 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1119 
1120 
1121 /*-------------------------------------------------------------------------*/
1122 
1123 /*
1124  * Generic HC operations.
1125  */
1126 
1127 /*-------------------------------------------------------------------------*/
1128 
1129 /**
1130  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1131  * @hcd: host controller to which @urb was submitted
1132  * @urb: URB being submitted
1133  *
1134  * Host controller drivers should call this routine in their enqueue()
1135  * method.  The HCD's private spinlock must be held and interrupts must
1136  * be disabled.  The actions carried out here are required for URB
1137  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1138  *
1139  * Return: 0 for no error, otherwise a negative error code (in which case
1140  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1141  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1142  * the private spinlock and returning.
1143  */
1144 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1145 {
1146 	int		rc = 0;
1147 
1148 	spin_lock(&hcd_urb_list_lock);
1149 
1150 	/* Check that the URB isn't being killed */
1151 	if (unlikely(atomic_read(&urb->reject))) {
1152 		rc = -EPERM;
1153 		goto done;
1154 	}
1155 
1156 	if (unlikely(!urb->ep->enabled)) {
1157 		rc = -ENOENT;
1158 		goto done;
1159 	}
1160 
1161 	if (unlikely(!urb->dev->can_submit)) {
1162 		rc = -EHOSTUNREACH;
1163 		goto done;
1164 	}
1165 
1166 	/*
1167 	 * Check the host controller's state and add the URB to the
1168 	 * endpoint's queue.
1169 	 */
1170 	if (HCD_RH_RUNNING(hcd)) {
1171 		urb->unlinked = 0;
1172 		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1173 	} else {
1174 		rc = -ESHUTDOWN;
1175 		goto done;
1176 	}
1177  done:
1178 	spin_unlock(&hcd_urb_list_lock);
1179 	return rc;
1180 }
1181 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1182 
1183 /**
1184  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1185  * @hcd: host controller to which @urb was submitted
1186  * @urb: URB being checked for unlinkability
1187  * @status: error code to store in @urb if the unlink succeeds
1188  *
1189  * Host controller drivers should call this routine in their dequeue()
1190  * method.  The HCD's private spinlock must be held and interrupts must
1191  * be disabled.  The actions carried out here are required for making
1192  * sure than an unlink is valid.
1193  *
1194  * Return: 0 for no error, otherwise a negative error code (in which case
1195  * the dequeue() method must fail).  The possible error codes are:
1196  *
1197  *	-EIDRM: @urb was not submitted or has already completed.
1198  *		The completion function may not have been called yet.
1199  *
1200  *	-EBUSY: @urb has already been unlinked.
1201  */
1202 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1203 		int status)
1204 {
1205 	struct list_head	*tmp;
1206 
1207 	/* insist the urb is still queued */
1208 	list_for_each(tmp, &urb->ep->urb_list) {
1209 		if (tmp == &urb->urb_list)
1210 			break;
1211 	}
1212 	if (tmp != &urb->urb_list)
1213 		return -EIDRM;
1214 
1215 	/* Any status except -EINPROGRESS means something already started to
1216 	 * unlink this URB from the hardware.  So there's no more work to do.
1217 	 */
1218 	if (urb->unlinked)
1219 		return -EBUSY;
1220 	urb->unlinked = status;
1221 	return 0;
1222 }
1223 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1224 
1225 /**
1226  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1227  * @hcd: host controller to which @urb was submitted
1228  * @urb: URB being unlinked
1229  *
1230  * Host controller drivers should call this routine before calling
1231  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1232  * interrupts must be disabled.  The actions carried out here are required
1233  * for URB completion.
1234  */
1235 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1236 {
1237 	/* clear all state linking urb to this dev (and hcd) */
1238 	spin_lock(&hcd_urb_list_lock);
1239 	list_del_init(&urb->urb_list);
1240 	spin_unlock(&hcd_urb_list_lock);
1241 }
1242 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1243 
1244 /*
1245  * Some usb host controllers can only perform dma using a small SRAM area.
1246  * The usb core itself is however optimized for host controllers that can dma
1247  * using regular system memory - like pci devices doing bus mastering.
1248  *
1249  * To support host controllers with limited dma capabilities we provide dma
1250  * bounce buffers. This feature can be enabled by initializing
1251  * hcd->localmem_pool using usb_hcd_setup_local_mem().
1252  *
1253  * The initialized hcd->localmem_pool then tells the usb code to allocate all
1254  * data for dma using the genalloc API.
1255  *
1256  * So, to summarize...
1257  *
1258  * - We need "local" memory, canonical example being
1259  *   a small SRAM on a discrete controller being the
1260  *   only memory that the controller can read ...
1261  *   (a) "normal" kernel memory is no good, and
1262  *   (b) there's not enough to share
1263  *
1264  * - So we use that, even though the primary requirement
1265  *   is that the memory be "local" (hence addressable
1266  *   by that device), not "coherent".
1267  *
1268  */
1269 
1270 static int hcd_alloc_coherent(struct usb_bus *bus,
1271 			      gfp_t mem_flags, dma_addr_t *dma_handle,
1272 			      void **vaddr_handle, size_t size,
1273 			      enum dma_data_direction dir)
1274 {
1275 	unsigned char *vaddr;
1276 
1277 	if (*vaddr_handle == NULL) {
1278 		WARN_ON_ONCE(1);
1279 		return -EFAULT;
1280 	}
1281 
1282 	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1283 				 mem_flags, dma_handle);
1284 	if (!vaddr)
1285 		return -ENOMEM;
1286 
1287 	/*
1288 	 * Store the virtual address of the buffer at the end
1289 	 * of the allocated dma buffer. The size of the buffer
1290 	 * may be uneven so use unaligned functions instead
1291 	 * of just rounding up. It makes sense to optimize for
1292 	 * memory footprint over access speed since the amount
1293 	 * of memory available for dma may be limited.
1294 	 */
1295 	put_unaligned((unsigned long)*vaddr_handle,
1296 		      (unsigned long *)(vaddr + size));
1297 
1298 	if (dir == DMA_TO_DEVICE)
1299 		memcpy(vaddr, *vaddr_handle, size);
1300 
1301 	*vaddr_handle = vaddr;
1302 	return 0;
1303 }
1304 
1305 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1306 			      void **vaddr_handle, size_t size,
1307 			      enum dma_data_direction dir)
1308 {
1309 	unsigned char *vaddr = *vaddr_handle;
1310 
1311 	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1312 
1313 	if (dir == DMA_FROM_DEVICE)
1314 		memcpy(vaddr, *vaddr_handle, size);
1315 
1316 	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1317 
1318 	*vaddr_handle = vaddr;
1319 	*dma_handle = 0;
1320 }
1321 
1322 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1323 {
1324 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1325 	    (urb->transfer_flags & URB_SETUP_MAP_SINGLE))
1326 		dma_unmap_single(hcd->self.sysdev,
1327 				urb->setup_dma,
1328 				sizeof(struct usb_ctrlrequest),
1329 				DMA_TO_DEVICE);
1330 	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1331 		hcd_free_coherent(urb->dev->bus,
1332 				&urb->setup_dma,
1333 				(void **) &urb->setup_packet,
1334 				sizeof(struct usb_ctrlrequest),
1335 				DMA_TO_DEVICE);
1336 
1337 	/* Make it safe to call this routine more than once */
1338 	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1339 }
1340 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1341 
1342 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1343 {
1344 	if (hcd->driver->unmap_urb_for_dma)
1345 		hcd->driver->unmap_urb_for_dma(hcd, urb);
1346 	else
1347 		usb_hcd_unmap_urb_for_dma(hcd, urb);
1348 }
1349 
1350 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1351 {
1352 	enum dma_data_direction dir;
1353 
1354 	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1355 
1356 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1357 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1358 	    (urb->transfer_flags & URB_DMA_MAP_SG))
1359 		dma_unmap_sg(hcd->self.sysdev,
1360 				urb->sg,
1361 				urb->num_sgs,
1362 				dir);
1363 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1364 		 (urb->transfer_flags & URB_DMA_MAP_PAGE))
1365 		dma_unmap_page(hcd->self.sysdev,
1366 				urb->transfer_dma,
1367 				urb->transfer_buffer_length,
1368 				dir);
1369 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1370 		 (urb->transfer_flags & URB_DMA_MAP_SINGLE))
1371 		dma_unmap_single(hcd->self.sysdev,
1372 				urb->transfer_dma,
1373 				urb->transfer_buffer_length,
1374 				dir);
1375 	else if (urb->transfer_flags & URB_MAP_LOCAL)
1376 		hcd_free_coherent(urb->dev->bus,
1377 				&urb->transfer_dma,
1378 				&urb->transfer_buffer,
1379 				urb->transfer_buffer_length,
1380 				dir);
1381 
1382 	/* Make it safe to call this routine more than once */
1383 	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1384 			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1385 }
1386 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1387 
1388 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1389 			   gfp_t mem_flags)
1390 {
1391 	if (hcd->driver->map_urb_for_dma)
1392 		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1393 	else
1394 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1395 }
1396 
1397 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1398 			    gfp_t mem_flags)
1399 {
1400 	enum dma_data_direction dir;
1401 	int ret = 0;
1402 
1403 	/* Map the URB's buffers for DMA access.
1404 	 * Lower level HCD code should use *_dma exclusively,
1405 	 * unless it uses pio or talks to another transport,
1406 	 * or uses the provided scatter gather list for bulk.
1407 	 */
1408 
1409 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1410 		if (hcd->self.uses_pio_for_control)
1411 			return ret;
1412 		if (hcd_uses_dma(hcd)) {
1413 			if (is_vmalloc_addr(urb->setup_packet)) {
1414 				WARN_ONCE(1, "setup packet is not dma capable\n");
1415 				return -EAGAIN;
1416 			} else if (object_is_on_stack(urb->setup_packet)) {
1417 				WARN_ONCE(1, "setup packet is on stack\n");
1418 				return -EAGAIN;
1419 			}
1420 
1421 			urb->setup_dma = dma_map_single(
1422 					hcd->self.sysdev,
1423 					urb->setup_packet,
1424 					sizeof(struct usb_ctrlrequest),
1425 					DMA_TO_DEVICE);
1426 			if (dma_mapping_error(hcd->self.sysdev,
1427 						urb->setup_dma))
1428 				return -EAGAIN;
1429 			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1430 		} else if (hcd->localmem_pool) {
1431 			ret = hcd_alloc_coherent(
1432 					urb->dev->bus, mem_flags,
1433 					&urb->setup_dma,
1434 					(void **)&urb->setup_packet,
1435 					sizeof(struct usb_ctrlrequest),
1436 					DMA_TO_DEVICE);
1437 			if (ret)
1438 				return ret;
1439 			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1440 		}
1441 	}
1442 
1443 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1444 	if (urb->transfer_buffer_length != 0
1445 	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1446 		if (hcd_uses_dma(hcd)) {
1447 			if (urb->num_sgs) {
1448 				int n;
1449 
1450 				/* We don't support sg for isoc transfers ! */
1451 				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1452 					WARN_ON(1);
1453 					return -EINVAL;
1454 				}
1455 
1456 				n = dma_map_sg(
1457 						hcd->self.sysdev,
1458 						urb->sg,
1459 						urb->num_sgs,
1460 						dir);
1461 				if (n <= 0)
1462 					ret = -EAGAIN;
1463 				else
1464 					urb->transfer_flags |= URB_DMA_MAP_SG;
1465 				urb->num_mapped_sgs = n;
1466 				if (n != urb->num_sgs)
1467 					urb->transfer_flags |=
1468 							URB_DMA_SG_COMBINED;
1469 			} else if (urb->sg) {
1470 				struct scatterlist *sg = urb->sg;
1471 				urb->transfer_dma = dma_map_page(
1472 						hcd->self.sysdev,
1473 						sg_page(sg),
1474 						sg->offset,
1475 						urb->transfer_buffer_length,
1476 						dir);
1477 				if (dma_mapping_error(hcd->self.sysdev,
1478 						urb->transfer_dma))
1479 					ret = -EAGAIN;
1480 				else
1481 					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1482 			} else if (is_vmalloc_addr(urb->transfer_buffer)) {
1483 				WARN_ONCE(1, "transfer buffer not dma capable\n");
1484 				ret = -EAGAIN;
1485 			} else if (object_is_on_stack(urb->transfer_buffer)) {
1486 				WARN_ONCE(1, "transfer buffer is on stack\n");
1487 				ret = -EAGAIN;
1488 			} else {
1489 				urb->transfer_dma = dma_map_single(
1490 						hcd->self.sysdev,
1491 						urb->transfer_buffer,
1492 						urb->transfer_buffer_length,
1493 						dir);
1494 				if (dma_mapping_error(hcd->self.sysdev,
1495 						urb->transfer_dma))
1496 					ret = -EAGAIN;
1497 				else
1498 					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1499 			}
1500 		} else if (hcd->localmem_pool) {
1501 			ret = hcd_alloc_coherent(
1502 					urb->dev->bus, mem_flags,
1503 					&urb->transfer_dma,
1504 					&urb->transfer_buffer,
1505 					urb->transfer_buffer_length,
1506 					dir);
1507 			if (ret == 0)
1508 				urb->transfer_flags |= URB_MAP_LOCAL;
1509 		}
1510 		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1511 				URB_SETUP_MAP_LOCAL)))
1512 			usb_hcd_unmap_urb_for_dma(hcd, urb);
1513 	}
1514 	return ret;
1515 }
1516 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1517 
1518 /*-------------------------------------------------------------------------*/
1519 
1520 /* may be called in any context with a valid urb->dev usecount
1521  * caller surrenders "ownership" of urb
1522  * expects usb_submit_urb() to have sanity checked and conditioned all
1523  * inputs in the urb
1524  */
1525 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1526 {
1527 	int			status;
1528 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1529 
1530 	/* increment urb's reference count as part of giving it to the HCD
1531 	 * (which will control it).  HCD guarantees that it either returns
1532 	 * an error or calls giveback(), but not both.
1533 	 */
1534 	usb_get_urb(urb);
1535 	atomic_inc(&urb->use_count);
1536 	atomic_inc(&urb->dev->urbnum);
1537 	usbmon_urb_submit(&hcd->self, urb);
1538 
1539 	/* NOTE requirements on root-hub callers (usbfs and the hub
1540 	 * driver, for now):  URBs' urb->transfer_buffer must be
1541 	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1542 	 * they could clobber root hub response data.  Also, control
1543 	 * URBs must be submitted in process context with interrupts
1544 	 * enabled.
1545 	 */
1546 
1547 	if (is_root_hub(urb->dev)) {
1548 		status = rh_urb_enqueue(hcd, urb);
1549 	} else {
1550 		status = map_urb_for_dma(hcd, urb, mem_flags);
1551 		if (likely(status == 0)) {
1552 			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1553 			if (unlikely(status))
1554 				unmap_urb_for_dma(hcd, urb);
1555 		}
1556 	}
1557 
1558 	if (unlikely(status)) {
1559 		usbmon_urb_submit_error(&hcd->self, urb, status);
1560 		urb->hcpriv = NULL;
1561 		INIT_LIST_HEAD(&urb->urb_list);
1562 		atomic_dec(&urb->use_count);
1563 		atomic_dec(&urb->dev->urbnum);
1564 		if (atomic_read(&urb->reject))
1565 			wake_up(&usb_kill_urb_queue);
1566 		usb_put_urb(urb);
1567 	}
1568 	return status;
1569 }
1570 
1571 /*-------------------------------------------------------------------------*/
1572 
1573 /* this makes the hcd giveback() the urb more quickly, by kicking it
1574  * off hardware queues (which may take a while) and returning it as
1575  * soon as practical.  we've already set up the urb's return status,
1576  * but we can't know if the callback completed already.
1577  */
1578 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1579 {
1580 	int		value;
1581 
1582 	if (is_root_hub(urb->dev))
1583 		value = usb_rh_urb_dequeue(hcd, urb, status);
1584 	else {
1585 
1586 		/* The only reason an HCD might fail this call is if
1587 		 * it has not yet fully queued the urb to begin with.
1588 		 * Such failures should be harmless. */
1589 		value = hcd->driver->urb_dequeue(hcd, urb, status);
1590 	}
1591 	return value;
1592 }
1593 
1594 /*
1595  * called in any context
1596  *
1597  * caller guarantees urb won't be recycled till both unlink()
1598  * and the urb's completion function return
1599  */
1600 int usb_hcd_unlink_urb (struct urb *urb, int status)
1601 {
1602 	struct usb_hcd		*hcd;
1603 	struct usb_device	*udev = urb->dev;
1604 	int			retval = -EIDRM;
1605 	unsigned long		flags;
1606 
1607 	/* Prevent the device and bus from going away while
1608 	 * the unlink is carried out.  If they are already gone
1609 	 * then urb->use_count must be 0, since disconnected
1610 	 * devices can't have any active URBs.
1611 	 */
1612 	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1613 	if (atomic_read(&urb->use_count) > 0) {
1614 		retval = 0;
1615 		usb_get_dev(udev);
1616 	}
1617 	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1618 	if (retval == 0) {
1619 		hcd = bus_to_hcd(urb->dev->bus);
1620 		retval = unlink1(hcd, urb, status);
1621 		if (retval == 0)
1622 			retval = -EINPROGRESS;
1623 		else if (retval != -EIDRM && retval != -EBUSY)
1624 			dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n",
1625 					urb, retval);
1626 		usb_put_dev(udev);
1627 	}
1628 	return retval;
1629 }
1630 
1631 /*-------------------------------------------------------------------------*/
1632 
1633 static void __usb_hcd_giveback_urb(struct urb *urb)
1634 {
1635 	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1636 	struct usb_anchor *anchor = urb->anchor;
1637 	int status = urb->unlinked;
1638 
1639 	urb->hcpriv = NULL;
1640 	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1641 	    urb->actual_length < urb->transfer_buffer_length &&
1642 	    !status))
1643 		status = -EREMOTEIO;
1644 
1645 	unmap_urb_for_dma(hcd, urb);
1646 	usbmon_urb_complete(&hcd->self, urb, status);
1647 	usb_anchor_suspend_wakeups(anchor);
1648 	usb_unanchor_urb(urb);
1649 	if (likely(status == 0))
1650 		usb_led_activity(USB_LED_EVENT_HOST);
1651 
1652 	/* pass ownership to the completion handler */
1653 	urb->status = status;
1654 	urb->complete(urb);
1655 
1656 	usb_anchor_resume_wakeups(anchor);
1657 	atomic_dec(&urb->use_count);
1658 	if (unlikely(atomic_read(&urb->reject)))
1659 		wake_up(&usb_kill_urb_queue);
1660 	usb_put_urb(urb);
1661 }
1662 
1663 static void usb_giveback_urb_bh(unsigned long param)
1664 {
1665 	struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param;
1666 	struct list_head local_list;
1667 
1668 	spin_lock_irq(&bh->lock);
1669 	bh->running = true;
1670  restart:
1671 	list_replace_init(&bh->head, &local_list);
1672 	spin_unlock_irq(&bh->lock);
1673 
1674 	while (!list_empty(&local_list)) {
1675 		struct urb *urb;
1676 
1677 		urb = list_entry(local_list.next, struct urb, urb_list);
1678 		list_del_init(&urb->urb_list);
1679 		bh->completing_ep = urb->ep;
1680 		__usb_hcd_giveback_urb(urb);
1681 		bh->completing_ep = NULL;
1682 	}
1683 
1684 	/* check if there are new URBs to giveback */
1685 	spin_lock_irq(&bh->lock);
1686 	if (!list_empty(&bh->head))
1687 		goto restart;
1688 	bh->running = false;
1689 	spin_unlock_irq(&bh->lock);
1690 }
1691 
1692 /**
1693  * usb_hcd_giveback_urb - return URB from HCD to device driver
1694  * @hcd: host controller returning the URB
1695  * @urb: urb being returned to the USB device driver.
1696  * @status: completion status code for the URB.
1697  * Context: in_interrupt()
1698  *
1699  * This hands the URB from HCD to its USB device driver, using its
1700  * completion function.  The HCD has freed all per-urb resources
1701  * (and is done using urb->hcpriv).  It also released all HCD locks;
1702  * the device driver won't cause problems if it frees, modifies,
1703  * or resubmits this URB.
1704  *
1705  * If @urb was unlinked, the value of @status will be overridden by
1706  * @urb->unlinked.  Erroneous short transfers are detected in case
1707  * the HCD hasn't checked for them.
1708  */
1709 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1710 {
1711 	struct giveback_urb_bh *bh;
1712 	bool running, high_prio_bh;
1713 
1714 	/* pass status to tasklet via unlinked */
1715 	if (likely(!urb->unlinked))
1716 		urb->unlinked = status;
1717 
1718 	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1719 		__usb_hcd_giveback_urb(urb);
1720 		return;
1721 	}
1722 
1723 	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
1724 		bh = &hcd->high_prio_bh;
1725 		high_prio_bh = true;
1726 	} else {
1727 		bh = &hcd->low_prio_bh;
1728 		high_prio_bh = false;
1729 	}
1730 
1731 	spin_lock(&bh->lock);
1732 	list_add_tail(&urb->urb_list, &bh->head);
1733 	running = bh->running;
1734 	spin_unlock(&bh->lock);
1735 
1736 	if (running)
1737 		;
1738 	else if (high_prio_bh)
1739 		tasklet_hi_schedule(&bh->bh);
1740 	else
1741 		tasklet_schedule(&bh->bh);
1742 }
1743 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1744 
1745 /*-------------------------------------------------------------------------*/
1746 
1747 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1748  * queue to drain completely.  The caller must first insure that no more
1749  * URBs can be submitted for this endpoint.
1750  */
1751 void usb_hcd_flush_endpoint(struct usb_device *udev,
1752 		struct usb_host_endpoint *ep)
1753 {
1754 	struct usb_hcd		*hcd;
1755 	struct urb		*urb;
1756 
1757 	if (!ep)
1758 		return;
1759 	might_sleep();
1760 	hcd = bus_to_hcd(udev->bus);
1761 
1762 	/* No more submits can occur */
1763 	spin_lock_irq(&hcd_urb_list_lock);
1764 rescan:
1765 	list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) {
1766 		int	is_in;
1767 
1768 		if (urb->unlinked)
1769 			continue;
1770 		usb_get_urb (urb);
1771 		is_in = usb_urb_dir_in(urb);
1772 		spin_unlock(&hcd_urb_list_lock);
1773 
1774 		/* kick hcd */
1775 		unlink1(hcd, urb, -ESHUTDOWN);
1776 		dev_dbg (hcd->self.controller,
1777 			"shutdown urb %pK ep%d%s-%s\n",
1778 			urb, usb_endpoint_num(&ep->desc),
1779 			is_in ? "in" : "out",
1780 			usb_ep_type_string(usb_endpoint_type(&ep->desc)));
1781 		usb_put_urb (urb);
1782 
1783 		/* list contents may have changed */
1784 		spin_lock(&hcd_urb_list_lock);
1785 		goto rescan;
1786 	}
1787 	spin_unlock_irq(&hcd_urb_list_lock);
1788 
1789 	/* Wait until the endpoint queue is completely empty */
1790 	while (!list_empty (&ep->urb_list)) {
1791 		spin_lock_irq(&hcd_urb_list_lock);
1792 
1793 		/* The list may have changed while we acquired the spinlock */
1794 		urb = NULL;
1795 		if (!list_empty (&ep->urb_list)) {
1796 			urb = list_entry (ep->urb_list.prev, struct urb,
1797 					urb_list);
1798 			usb_get_urb (urb);
1799 		}
1800 		spin_unlock_irq(&hcd_urb_list_lock);
1801 
1802 		if (urb) {
1803 			usb_kill_urb (urb);
1804 			usb_put_urb (urb);
1805 		}
1806 	}
1807 }
1808 
1809 /**
1810  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1811  *				the bus bandwidth
1812  * @udev: target &usb_device
1813  * @new_config: new configuration to install
1814  * @cur_alt: the current alternate interface setting
1815  * @new_alt: alternate interface setting that is being installed
1816  *
1817  * To change configurations, pass in the new configuration in new_config,
1818  * and pass NULL for cur_alt and new_alt.
1819  *
1820  * To reset a device's configuration (put the device in the ADDRESSED state),
1821  * pass in NULL for new_config, cur_alt, and new_alt.
1822  *
1823  * To change alternate interface settings, pass in NULL for new_config,
1824  * pass in the current alternate interface setting in cur_alt,
1825  * and pass in the new alternate interface setting in new_alt.
1826  *
1827  * Return: An error if the requested bandwidth change exceeds the
1828  * bus bandwidth or host controller internal resources.
1829  */
1830 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1831 		struct usb_host_config *new_config,
1832 		struct usb_host_interface *cur_alt,
1833 		struct usb_host_interface *new_alt)
1834 {
1835 	int num_intfs, i, j;
1836 	struct usb_host_interface *alt = NULL;
1837 	int ret = 0;
1838 	struct usb_hcd *hcd;
1839 	struct usb_host_endpoint *ep;
1840 
1841 	hcd = bus_to_hcd(udev->bus);
1842 	if (!hcd->driver->check_bandwidth)
1843 		return 0;
1844 
1845 	/* Configuration is being removed - set configuration 0 */
1846 	if (!new_config && !cur_alt) {
1847 		for (i = 1; i < 16; ++i) {
1848 			ep = udev->ep_out[i];
1849 			if (ep)
1850 				hcd->driver->drop_endpoint(hcd, udev, ep);
1851 			ep = udev->ep_in[i];
1852 			if (ep)
1853 				hcd->driver->drop_endpoint(hcd, udev, ep);
1854 		}
1855 		hcd->driver->check_bandwidth(hcd, udev);
1856 		return 0;
1857 	}
1858 	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1859 	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1860 	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1861 	 * ok to exclude it.
1862 	 */
1863 	if (new_config) {
1864 		num_intfs = new_config->desc.bNumInterfaces;
1865 		/* Remove endpoints (except endpoint 0, which is always on the
1866 		 * schedule) from the old config from the schedule
1867 		 */
1868 		for (i = 1; i < 16; ++i) {
1869 			ep = udev->ep_out[i];
1870 			if (ep) {
1871 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1872 				if (ret < 0)
1873 					goto reset;
1874 			}
1875 			ep = udev->ep_in[i];
1876 			if (ep) {
1877 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1878 				if (ret < 0)
1879 					goto reset;
1880 			}
1881 		}
1882 		for (i = 0; i < num_intfs; ++i) {
1883 			struct usb_host_interface *first_alt;
1884 			int iface_num;
1885 
1886 			first_alt = &new_config->intf_cache[i]->altsetting[0];
1887 			iface_num = first_alt->desc.bInterfaceNumber;
1888 			/* Set up endpoints for alternate interface setting 0 */
1889 			alt = usb_find_alt_setting(new_config, iface_num, 0);
1890 			if (!alt)
1891 				/* No alt setting 0? Pick the first setting. */
1892 				alt = first_alt;
1893 
1894 			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1895 				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1896 				if (ret < 0)
1897 					goto reset;
1898 			}
1899 		}
1900 	}
1901 	if (cur_alt && new_alt) {
1902 		struct usb_interface *iface = usb_ifnum_to_if(udev,
1903 				cur_alt->desc.bInterfaceNumber);
1904 
1905 		if (!iface)
1906 			return -EINVAL;
1907 		if (iface->resetting_device) {
1908 			/*
1909 			 * The USB core just reset the device, so the xHCI host
1910 			 * and the device will think alt setting 0 is installed.
1911 			 * However, the USB core will pass in the alternate
1912 			 * setting installed before the reset as cur_alt.  Dig
1913 			 * out the alternate setting 0 structure, or the first
1914 			 * alternate setting if a broken device doesn't have alt
1915 			 * setting 0.
1916 			 */
1917 			cur_alt = usb_altnum_to_altsetting(iface, 0);
1918 			if (!cur_alt)
1919 				cur_alt = &iface->altsetting[0];
1920 		}
1921 
1922 		/* Drop all the endpoints in the current alt setting */
1923 		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
1924 			ret = hcd->driver->drop_endpoint(hcd, udev,
1925 					&cur_alt->endpoint[i]);
1926 			if (ret < 0)
1927 				goto reset;
1928 		}
1929 		/* Add all the endpoints in the new alt setting */
1930 		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
1931 			ret = hcd->driver->add_endpoint(hcd, udev,
1932 					&new_alt->endpoint[i]);
1933 			if (ret < 0)
1934 				goto reset;
1935 		}
1936 	}
1937 	ret = hcd->driver->check_bandwidth(hcd, udev);
1938 reset:
1939 	if (ret < 0)
1940 		hcd->driver->reset_bandwidth(hcd, udev);
1941 	return ret;
1942 }
1943 
1944 /* Disables the endpoint: synchronizes with the hcd to make sure all
1945  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
1946  * have been called previously.  Use for set_configuration, set_interface,
1947  * driver removal, physical disconnect.
1948  *
1949  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
1950  * type, maxpacket size, toggle, halt status, and scheduling.
1951  */
1952 void usb_hcd_disable_endpoint(struct usb_device *udev,
1953 		struct usb_host_endpoint *ep)
1954 {
1955 	struct usb_hcd		*hcd;
1956 
1957 	might_sleep();
1958 	hcd = bus_to_hcd(udev->bus);
1959 	if (hcd->driver->endpoint_disable)
1960 		hcd->driver->endpoint_disable(hcd, ep);
1961 }
1962 
1963 /**
1964  * usb_hcd_reset_endpoint - reset host endpoint state
1965  * @udev: USB device.
1966  * @ep:   the endpoint to reset.
1967  *
1968  * Resets any host endpoint state such as the toggle bit, sequence
1969  * number and current window.
1970  */
1971 void usb_hcd_reset_endpoint(struct usb_device *udev,
1972 			    struct usb_host_endpoint *ep)
1973 {
1974 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1975 
1976 	if (hcd->driver->endpoint_reset)
1977 		hcd->driver->endpoint_reset(hcd, ep);
1978 	else {
1979 		int epnum = usb_endpoint_num(&ep->desc);
1980 		int is_out = usb_endpoint_dir_out(&ep->desc);
1981 		int is_control = usb_endpoint_xfer_control(&ep->desc);
1982 
1983 		usb_settoggle(udev, epnum, is_out, 0);
1984 		if (is_control)
1985 			usb_settoggle(udev, epnum, !is_out, 0);
1986 	}
1987 }
1988 
1989 /**
1990  * usb_alloc_streams - allocate bulk endpoint stream IDs.
1991  * @interface:		alternate setting that includes all endpoints.
1992  * @eps:		array of endpoints that need streams.
1993  * @num_eps:		number of endpoints in the array.
1994  * @num_streams:	number of streams to allocate.
1995  * @mem_flags:		flags hcd should use to allocate memory.
1996  *
1997  * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
1998  * Drivers may queue multiple transfers to different stream IDs, which may
1999  * complete in a different order than they were queued.
2000  *
2001  * Return: On success, the number of allocated streams. On failure, a negative
2002  * error code.
2003  */
2004 int usb_alloc_streams(struct usb_interface *interface,
2005 		struct usb_host_endpoint **eps, unsigned int num_eps,
2006 		unsigned int num_streams, gfp_t mem_flags)
2007 {
2008 	struct usb_hcd *hcd;
2009 	struct usb_device *dev;
2010 	int i, ret;
2011 
2012 	dev = interface_to_usbdev(interface);
2013 	hcd = bus_to_hcd(dev->bus);
2014 	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2015 		return -EINVAL;
2016 	if (dev->speed < USB_SPEED_SUPER)
2017 		return -EINVAL;
2018 	if (dev->state < USB_STATE_CONFIGURED)
2019 		return -ENODEV;
2020 
2021 	for (i = 0; i < num_eps; i++) {
2022 		/* Streams only apply to bulk endpoints. */
2023 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2024 			return -EINVAL;
2025 		/* Re-alloc is not allowed */
2026 		if (eps[i]->streams)
2027 			return -EINVAL;
2028 	}
2029 
2030 	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2031 			num_streams, mem_flags);
2032 	if (ret < 0)
2033 		return ret;
2034 
2035 	for (i = 0; i < num_eps; i++)
2036 		eps[i]->streams = ret;
2037 
2038 	return ret;
2039 }
2040 EXPORT_SYMBOL_GPL(usb_alloc_streams);
2041 
2042 /**
2043  * usb_free_streams - free bulk endpoint stream IDs.
2044  * @interface:	alternate setting that includes all endpoints.
2045  * @eps:	array of endpoints to remove streams from.
2046  * @num_eps:	number of endpoints in the array.
2047  * @mem_flags:	flags hcd should use to allocate memory.
2048  *
2049  * Reverts a group of bulk endpoints back to not using stream IDs.
2050  * Can fail if we are given bad arguments, or HCD is broken.
2051  *
2052  * Return: 0 on success. On failure, a negative error code.
2053  */
2054 int usb_free_streams(struct usb_interface *interface,
2055 		struct usb_host_endpoint **eps, unsigned int num_eps,
2056 		gfp_t mem_flags)
2057 {
2058 	struct usb_hcd *hcd;
2059 	struct usb_device *dev;
2060 	int i, ret;
2061 
2062 	dev = interface_to_usbdev(interface);
2063 	hcd = bus_to_hcd(dev->bus);
2064 	if (dev->speed < USB_SPEED_SUPER)
2065 		return -EINVAL;
2066 
2067 	/* Double-free is not allowed */
2068 	for (i = 0; i < num_eps; i++)
2069 		if (!eps[i] || !eps[i]->streams)
2070 			return -EINVAL;
2071 
2072 	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2073 	if (ret < 0)
2074 		return ret;
2075 
2076 	for (i = 0; i < num_eps; i++)
2077 		eps[i]->streams = 0;
2078 
2079 	return ret;
2080 }
2081 EXPORT_SYMBOL_GPL(usb_free_streams);
2082 
2083 /* Protect against drivers that try to unlink URBs after the device
2084  * is gone, by waiting until all unlinks for @udev are finished.
2085  * Since we don't currently track URBs by device, simply wait until
2086  * nothing is running in the locked region of usb_hcd_unlink_urb().
2087  */
2088 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2089 {
2090 	spin_lock_irq(&hcd_urb_unlink_lock);
2091 	spin_unlock_irq(&hcd_urb_unlink_lock);
2092 }
2093 
2094 /*-------------------------------------------------------------------------*/
2095 
2096 /* called in any context */
2097 int usb_hcd_get_frame_number (struct usb_device *udev)
2098 {
2099 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
2100 
2101 	if (!HCD_RH_RUNNING(hcd))
2102 		return -ESHUTDOWN;
2103 	return hcd->driver->get_frame_number (hcd);
2104 }
2105 
2106 /*-------------------------------------------------------------------------*/
2107 
2108 #ifdef	CONFIG_PM
2109 
2110 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2111 {
2112 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2113 	int		status;
2114 	int		old_state = hcd->state;
2115 
2116 	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2117 			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2118 			rhdev->do_remote_wakeup);
2119 	if (HCD_DEAD(hcd)) {
2120 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2121 		return 0;
2122 	}
2123 
2124 	if (!hcd->driver->bus_suspend) {
2125 		status = -ENOENT;
2126 	} else {
2127 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2128 		hcd->state = HC_STATE_QUIESCING;
2129 		status = hcd->driver->bus_suspend(hcd);
2130 	}
2131 	if (status == 0) {
2132 		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2133 		hcd->state = HC_STATE_SUSPENDED;
2134 
2135 		if (!PMSG_IS_AUTO(msg))
2136 			usb_phy_roothub_suspend(hcd->self.sysdev,
2137 						hcd->phy_roothub);
2138 
2139 		/* Did we race with a root-hub wakeup event? */
2140 		if (rhdev->do_remote_wakeup) {
2141 			char	buffer[6];
2142 
2143 			status = hcd->driver->hub_status_data(hcd, buffer);
2144 			if (status != 0) {
2145 				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2146 				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2147 				status = -EBUSY;
2148 			}
2149 		}
2150 	} else {
2151 		spin_lock_irq(&hcd_root_hub_lock);
2152 		if (!HCD_DEAD(hcd)) {
2153 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2154 			hcd->state = old_state;
2155 		}
2156 		spin_unlock_irq(&hcd_root_hub_lock);
2157 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2158 				"suspend", status);
2159 	}
2160 	return status;
2161 }
2162 
2163 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2164 {
2165 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2166 	int		status;
2167 	int		old_state = hcd->state;
2168 
2169 	dev_dbg(&rhdev->dev, "usb %sresume\n",
2170 			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2171 	if (HCD_DEAD(hcd)) {
2172 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2173 		return 0;
2174 	}
2175 
2176 	if (!PMSG_IS_AUTO(msg)) {
2177 		status = usb_phy_roothub_resume(hcd->self.sysdev,
2178 						hcd->phy_roothub);
2179 		if (status)
2180 			return status;
2181 	}
2182 
2183 	if (!hcd->driver->bus_resume)
2184 		return -ENOENT;
2185 	if (HCD_RH_RUNNING(hcd))
2186 		return 0;
2187 
2188 	hcd->state = HC_STATE_RESUMING;
2189 	status = hcd->driver->bus_resume(hcd);
2190 	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2191 	if (status == 0)
2192 		status = usb_phy_roothub_calibrate(hcd->phy_roothub);
2193 
2194 	if (status == 0) {
2195 		struct usb_device *udev;
2196 		int port1;
2197 
2198 		spin_lock_irq(&hcd_root_hub_lock);
2199 		if (!HCD_DEAD(hcd)) {
2200 			usb_set_device_state(rhdev, rhdev->actconfig
2201 					? USB_STATE_CONFIGURED
2202 					: USB_STATE_ADDRESS);
2203 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2204 			hcd->state = HC_STATE_RUNNING;
2205 		}
2206 		spin_unlock_irq(&hcd_root_hub_lock);
2207 
2208 		/*
2209 		 * Check whether any of the enabled ports on the root hub are
2210 		 * unsuspended.  If they are then a TRSMRCY delay is needed
2211 		 * (this is what the USB-2 spec calls a "global resume").
2212 		 * Otherwise we can skip the delay.
2213 		 */
2214 		usb_hub_for_each_child(rhdev, port1, udev) {
2215 			if (udev->state != USB_STATE_NOTATTACHED &&
2216 					!udev->port_is_suspended) {
2217 				usleep_range(10000, 11000);	/* TRSMRCY */
2218 				break;
2219 			}
2220 		}
2221 	} else {
2222 		hcd->state = old_state;
2223 		usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub);
2224 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2225 				"resume", status);
2226 		if (status != -ESHUTDOWN)
2227 			usb_hc_died(hcd);
2228 	}
2229 	return status;
2230 }
2231 
2232 /* Workqueue routine for root-hub remote wakeup */
2233 static void hcd_resume_work(struct work_struct *work)
2234 {
2235 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2236 	struct usb_device *udev = hcd->self.root_hub;
2237 
2238 	usb_remote_wakeup(udev);
2239 }
2240 
2241 /**
2242  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2243  * @hcd: host controller for this root hub
2244  *
2245  * The USB host controller calls this function when its root hub is
2246  * suspended (with the remote wakeup feature enabled) and a remote
2247  * wakeup request is received.  The routine submits a workqueue request
2248  * to resume the root hub (that is, manage its downstream ports again).
2249  */
2250 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2251 {
2252 	unsigned long flags;
2253 
2254 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2255 	if (hcd->rh_registered) {
2256 		pm_wakeup_event(&hcd->self.root_hub->dev, 0);
2257 		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2258 		queue_work(pm_wq, &hcd->wakeup_work);
2259 	}
2260 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2261 }
2262 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2263 
2264 #endif	/* CONFIG_PM */
2265 
2266 /*-------------------------------------------------------------------------*/
2267 
2268 #ifdef	CONFIG_USB_OTG
2269 
2270 /**
2271  * usb_bus_start_enum - start immediate enumeration (for OTG)
2272  * @bus: the bus (must use hcd framework)
2273  * @port_num: 1-based number of port; usually bus->otg_port
2274  * Context: in_interrupt()
2275  *
2276  * Starts enumeration, with an immediate reset followed later by
2277  * hub_wq identifying and possibly configuring the device.
2278  * This is needed by OTG controller drivers, where it helps meet
2279  * HNP protocol timing requirements for starting a port reset.
2280  *
2281  * Return: 0 if successful.
2282  */
2283 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2284 {
2285 	struct usb_hcd		*hcd;
2286 	int			status = -EOPNOTSUPP;
2287 
2288 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2289 	 * boards with root hubs hooked up to internal devices (instead of
2290 	 * just the OTG port) may need more attention to resetting...
2291 	 */
2292 	hcd = bus_to_hcd(bus);
2293 	if (port_num && hcd->driver->start_port_reset)
2294 		status = hcd->driver->start_port_reset(hcd, port_num);
2295 
2296 	/* allocate hub_wq shortly after (first) root port reset finishes;
2297 	 * it may issue others, until at least 50 msecs have passed.
2298 	 */
2299 	if (status == 0)
2300 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2301 	return status;
2302 }
2303 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2304 
2305 #endif
2306 
2307 /*-------------------------------------------------------------------------*/
2308 
2309 /**
2310  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2311  * @irq: the IRQ being raised
2312  * @__hcd: pointer to the HCD whose IRQ is being signaled
2313  *
2314  * If the controller isn't HALTed, calls the driver's irq handler.
2315  * Checks whether the controller is now dead.
2316  *
2317  * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2318  */
2319 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2320 {
2321 	struct usb_hcd		*hcd = __hcd;
2322 	irqreturn_t		rc;
2323 
2324 	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2325 		rc = IRQ_NONE;
2326 	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2327 		rc = IRQ_NONE;
2328 	else
2329 		rc = IRQ_HANDLED;
2330 
2331 	return rc;
2332 }
2333 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2334 
2335 /*-------------------------------------------------------------------------*/
2336 
2337 /* Workqueue routine for when the root-hub has died. */
2338 static void hcd_died_work(struct work_struct *work)
2339 {
2340 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, died_work);
2341 	static char *env[] = {
2342 		"ERROR=DEAD",
2343 		NULL
2344 	};
2345 
2346 	/* Notify user space that the host controller has died */
2347 	kobject_uevent_env(&hcd->self.root_hub->dev.kobj, KOBJ_OFFLINE, env);
2348 }
2349 
2350 /**
2351  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2352  * @hcd: pointer to the HCD representing the controller
2353  *
2354  * This is called by bus glue to report a USB host controller that died
2355  * while operations may still have been pending.  It's called automatically
2356  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2357  *
2358  * Only call this function with the primary HCD.
2359  */
2360 void usb_hc_died (struct usb_hcd *hcd)
2361 {
2362 	unsigned long flags;
2363 
2364 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2365 
2366 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2367 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2368 	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2369 	if (hcd->rh_registered) {
2370 		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2371 
2372 		/* make hub_wq clean up old urbs and devices */
2373 		usb_set_device_state (hcd->self.root_hub,
2374 				USB_STATE_NOTATTACHED);
2375 		usb_kick_hub_wq(hcd->self.root_hub);
2376 	}
2377 	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2378 		hcd = hcd->shared_hcd;
2379 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2380 		set_bit(HCD_FLAG_DEAD, &hcd->flags);
2381 		if (hcd->rh_registered) {
2382 			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2383 
2384 			/* make hub_wq clean up old urbs and devices */
2385 			usb_set_device_state(hcd->self.root_hub,
2386 					USB_STATE_NOTATTACHED);
2387 			usb_kick_hub_wq(hcd->self.root_hub);
2388 		}
2389 	}
2390 
2391 	/* Handle the case where this function gets called with a shared HCD */
2392 	if (usb_hcd_is_primary_hcd(hcd))
2393 		schedule_work(&hcd->died_work);
2394 	else
2395 		schedule_work(&hcd->primary_hcd->died_work);
2396 
2397 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2398 	/* Make sure that the other roothub is also deallocated. */
2399 }
2400 EXPORT_SYMBOL_GPL (usb_hc_died);
2401 
2402 /*-------------------------------------------------------------------------*/
2403 
2404 static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2405 {
2406 
2407 	spin_lock_init(&bh->lock);
2408 	INIT_LIST_HEAD(&bh->head);
2409 	tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh);
2410 }
2411 
2412 struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
2413 		struct device *sysdev, struct device *dev, const char *bus_name,
2414 		struct usb_hcd *primary_hcd)
2415 {
2416 	struct usb_hcd *hcd;
2417 
2418 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2419 	if (!hcd)
2420 		return NULL;
2421 	if (primary_hcd == NULL) {
2422 		hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex),
2423 				GFP_KERNEL);
2424 		if (!hcd->address0_mutex) {
2425 			kfree(hcd);
2426 			dev_dbg(dev, "hcd address0 mutex alloc failed\n");
2427 			return NULL;
2428 		}
2429 		mutex_init(hcd->address0_mutex);
2430 		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2431 				GFP_KERNEL);
2432 		if (!hcd->bandwidth_mutex) {
2433 			kfree(hcd->address0_mutex);
2434 			kfree(hcd);
2435 			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2436 			return NULL;
2437 		}
2438 		mutex_init(hcd->bandwidth_mutex);
2439 		dev_set_drvdata(dev, hcd);
2440 	} else {
2441 		mutex_lock(&usb_port_peer_mutex);
2442 		hcd->address0_mutex = primary_hcd->address0_mutex;
2443 		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2444 		hcd->primary_hcd = primary_hcd;
2445 		primary_hcd->primary_hcd = primary_hcd;
2446 		hcd->shared_hcd = primary_hcd;
2447 		primary_hcd->shared_hcd = hcd;
2448 		mutex_unlock(&usb_port_peer_mutex);
2449 	}
2450 
2451 	kref_init(&hcd->kref);
2452 
2453 	usb_bus_init(&hcd->self);
2454 	hcd->self.controller = dev;
2455 	hcd->self.sysdev = sysdev;
2456 	hcd->self.bus_name = bus_name;
2457 
2458 	timer_setup(&hcd->rh_timer, rh_timer_func, 0);
2459 #ifdef CONFIG_PM
2460 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2461 #endif
2462 
2463 	INIT_WORK(&hcd->died_work, hcd_died_work);
2464 
2465 	hcd->driver = driver;
2466 	hcd->speed = driver->flags & HCD_MASK;
2467 	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2468 			"USB Host Controller";
2469 	return hcd;
2470 }
2471 EXPORT_SYMBOL_GPL(__usb_create_hcd);
2472 
2473 /**
2474  * usb_create_shared_hcd - create and initialize an HCD structure
2475  * @driver: HC driver that will use this hcd
2476  * @dev: device for this HC, stored in hcd->self.controller
2477  * @bus_name: value to store in hcd->self.bus_name
2478  * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2479  *              PCI device.  Only allocate certain resources for the primary HCD
2480  * Context: !in_interrupt()
2481  *
2482  * Allocate a struct usb_hcd, with extra space at the end for the
2483  * HC driver's private data.  Initialize the generic members of the
2484  * hcd structure.
2485  *
2486  * Return: On success, a pointer to the created and initialized HCD structure.
2487  * On failure (e.g. if memory is unavailable), %NULL.
2488  */
2489 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2490 		struct device *dev, const char *bus_name,
2491 		struct usb_hcd *primary_hcd)
2492 {
2493 	return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd);
2494 }
2495 EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2496 
2497 /**
2498  * usb_create_hcd - create and initialize an HCD structure
2499  * @driver: HC driver that will use this hcd
2500  * @dev: device for this HC, stored in hcd->self.controller
2501  * @bus_name: value to store in hcd->self.bus_name
2502  * Context: !in_interrupt()
2503  *
2504  * Allocate a struct usb_hcd, with extra space at the end for the
2505  * HC driver's private data.  Initialize the generic members of the
2506  * hcd structure.
2507  *
2508  * Return: On success, a pointer to the created and initialized HCD
2509  * structure. On failure (e.g. if memory is unavailable), %NULL.
2510  */
2511 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2512 		struct device *dev, const char *bus_name)
2513 {
2514 	return __usb_create_hcd(driver, dev, dev, bus_name, NULL);
2515 }
2516 EXPORT_SYMBOL_GPL(usb_create_hcd);
2517 
2518 /*
2519  * Roothubs that share one PCI device must also share the bandwidth mutex.
2520  * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2521  * deallocated.
2522  *
2523  * Make sure to deallocate the bandwidth_mutex only when the last HCD is
2524  * freed.  When hcd_release() is called for either hcd in a peer set,
2525  * invalidate the peer's ->shared_hcd and ->primary_hcd pointers.
2526  */
2527 static void hcd_release(struct kref *kref)
2528 {
2529 	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2530 
2531 	mutex_lock(&usb_port_peer_mutex);
2532 	if (hcd->shared_hcd) {
2533 		struct usb_hcd *peer = hcd->shared_hcd;
2534 
2535 		peer->shared_hcd = NULL;
2536 		peer->primary_hcd = NULL;
2537 	} else {
2538 		kfree(hcd->address0_mutex);
2539 		kfree(hcd->bandwidth_mutex);
2540 	}
2541 	mutex_unlock(&usb_port_peer_mutex);
2542 	kfree(hcd);
2543 }
2544 
2545 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2546 {
2547 	if (hcd)
2548 		kref_get (&hcd->kref);
2549 	return hcd;
2550 }
2551 EXPORT_SYMBOL_GPL(usb_get_hcd);
2552 
2553 void usb_put_hcd (struct usb_hcd *hcd)
2554 {
2555 	if (hcd)
2556 		kref_put (&hcd->kref, hcd_release);
2557 }
2558 EXPORT_SYMBOL_GPL(usb_put_hcd);
2559 
2560 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2561 {
2562 	if (!hcd->primary_hcd)
2563 		return 1;
2564 	return hcd == hcd->primary_hcd;
2565 }
2566 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2567 
2568 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2569 {
2570 	if (!hcd->driver->find_raw_port_number)
2571 		return port1;
2572 
2573 	return hcd->driver->find_raw_port_number(hcd, port1);
2574 }
2575 
2576 static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2577 		unsigned int irqnum, unsigned long irqflags)
2578 {
2579 	int retval;
2580 
2581 	if (hcd->driver->irq) {
2582 
2583 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2584 				hcd->driver->description, hcd->self.busnum);
2585 		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2586 				hcd->irq_descr, hcd);
2587 		if (retval != 0) {
2588 			dev_err(hcd->self.controller,
2589 					"request interrupt %d failed\n",
2590 					irqnum);
2591 			return retval;
2592 		}
2593 		hcd->irq = irqnum;
2594 		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2595 				(hcd->driver->flags & HCD_MEMORY) ?
2596 					"io mem" : "io base",
2597 					(unsigned long long)hcd->rsrc_start);
2598 	} else {
2599 		hcd->irq = 0;
2600 		if (hcd->rsrc_start)
2601 			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2602 					(hcd->driver->flags & HCD_MEMORY) ?
2603 					"io mem" : "io base",
2604 					(unsigned long long)hcd->rsrc_start);
2605 	}
2606 	return 0;
2607 }
2608 
2609 /*
2610  * Before we free this root hub, flush in-flight peering attempts
2611  * and disable peer lookups
2612  */
2613 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2614 {
2615 	struct usb_device *rhdev;
2616 
2617 	mutex_lock(&usb_port_peer_mutex);
2618 	rhdev = hcd->self.root_hub;
2619 	hcd->self.root_hub = NULL;
2620 	mutex_unlock(&usb_port_peer_mutex);
2621 	usb_put_dev(rhdev);
2622 }
2623 
2624 /**
2625  * usb_add_hcd - finish generic HCD structure initialization and register
2626  * @hcd: the usb_hcd structure to initialize
2627  * @irqnum: Interrupt line to allocate
2628  * @irqflags: Interrupt type flags
2629  *
2630  * Finish the remaining parts of generic HCD initialization: allocate the
2631  * buffers of consistent memory, register the bus, request the IRQ line,
2632  * and call the driver's reset() and start() routines.
2633  */
2634 int usb_add_hcd(struct usb_hcd *hcd,
2635 		unsigned int irqnum, unsigned long irqflags)
2636 {
2637 	int retval;
2638 	struct usb_device *rhdev;
2639 
2640 	if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) {
2641 		hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev);
2642 		if (IS_ERR(hcd->phy_roothub))
2643 			return PTR_ERR(hcd->phy_roothub);
2644 
2645 		retval = usb_phy_roothub_init(hcd->phy_roothub);
2646 		if (retval)
2647 			return retval;
2648 
2649 		retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2650 						  PHY_MODE_USB_HOST_SS);
2651 		if (retval)
2652 			retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2653 							  PHY_MODE_USB_HOST);
2654 		if (retval)
2655 			goto err_usb_phy_roothub_power_on;
2656 
2657 		retval = usb_phy_roothub_power_on(hcd->phy_roothub);
2658 		if (retval)
2659 			goto err_usb_phy_roothub_power_on;
2660 	}
2661 
2662 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2663 
2664 	switch (authorized_default) {
2665 	case USB_AUTHORIZE_NONE:
2666 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_NONE;
2667 		break;
2668 
2669 	case USB_AUTHORIZE_ALL:
2670 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_ALL;
2671 		break;
2672 
2673 	case USB_AUTHORIZE_INTERNAL:
2674 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_INTERNAL;
2675 		break;
2676 
2677 	case USB_AUTHORIZE_WIRED:
2678 	default:
2679 		hcd->dev_policy = hcd->wireless ?
2680 			USB_DEVICE_AUTHORIZE_NONE : USB_DEVICE_AUTHORIZE_ALL;
2681 		break;
2682 	}
2683 
2684 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2685 
2686 	/* per default all interfaces are authorized */
2687 	set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
2688 
2689 	/* HC is in reset state, but accessible.  Now do the one-time init,
2690 	 * bottom up so that hcds can customize the root hubs before hub_wq
2691 	 * starts talking to them.  (Note, bus id is assigned early too.)
2692 	 */
2693 	retval = hcd_buffer_create(hcd);
2694 	if (retval != 0) {
2695 		dev_dbg(hcd->self.sysdev, "pool alloc failed\n");
2696 		goto err_create_buf;
2697 	}
2698 
2699 	retval = usb_register_bus(&hcd->self);
2700 	if (retval < 0)
2701 		goto err_register_bus;
2702 
2703 	rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2704 	if (rhdev == NULL) {
2705 		dev_err(hcd->self.sysdev, "unable to allocate root hub\n");
2706 		retval = -ENOMEM;
2707 		goto err_allocate_root_hub;
2708 	}
2709 	mutex_lock(&usb_port_peer_mutex);
2710 	hcd->self.root_hub = rhdev;
2711 	mutex_unlock(&usb_port_peer_mutex);
2712 
2713 	rhdev->rx_lanes = 1;
2714 	rhdev->tx_lanes = 1;
2715 
2716 	switch (hcd->speed) {
2717 	case HCD_USB11:
2718 		rhdev->speed = USB_SPEED_FULL;
2719 		break;
2720 	case HCD_USB2:
2721 		rhdev->speed = USB_SPEED_HIGH;
2722 		break;
2723 	case HCD_USB25:
2724 		rhdev->speed = USB_SPEED_WIRELESS;
2725 		break;
2726 	case HCD_USB3:
2727 		rhdev->speed = USB_SPEED_SUPER;
2728 		break;
2729 	case HCD_USB32:
2730 		rhdev->rx_lanes = 2;
2731 		rhdev->tx_lanes = 2;
2732 		/* fall through */
2733 	case HCD_USB31:
2734 		rhdev->speed = USB_SPEED_SUPER_PLUS;
2735 		break;
2736 	default:
2737 		retval = -EINVAL;
2738 		goto err_set_rh_speed;
2739 	}
2740 
2741 	/* wakeup flag init defaults to "everything works" for root hubs,
2742 	 * but drivers can override it in reset() if needed, along with
2743 	 * recording the overall controller's system wakeup capability.
2744 	 */
2745 	device_set_wakeup_capable(&rhdev->dev, 1);
2746 
2747 	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2748 	 * registered.  But since the controller can die at any time,
2749 	 * let's initialize the flag before touching the hardware.
2750 	 */
2751 	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2752 
2753 	/* "reset" is misnamed; its role is now one-time init. the controller
2754 	 * should already have been reset (and boot firmware kicked off etc).
2755 	 */
2756 	if (hcd->driver->reset) {
2757 		retval = hcd->driver->reset(hcd);
2758 		if (retval < 0) {
2759 			dev_err(hcd->self.controller, "can't setup: %d\n",
2760 					retval);
2761 			goto err_hcd_driver_setup;
2762 		}
2763 	}
2764 	hcd->rh_pollable = 1;
2765 
2766 	retval = usb_phy_roothub_calibrate(hcd->phy_roothub);
2767 	if (retval)
2768 		goto err_hcd_driver_setup;
2769 
2770 	/* NOTE: root hub and controller capabilities may not be the same */
2771 	if (device_can_wakeup(hcd->self.controller)
2772 			&& device_can_wakeup(&hcd->self.root_hub->dev))
2773 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2774 
2775 	/* initialize tasklets */
2776 	init_giveback_urb_bh(&hcd->high_prio_bh);
2777 	init_giveback_urb_bh(&hcd->low_prio_bh);
2778 
2779 	/* enable irqs just before we start the controller,
2780 	 * if the BIOS provides legacy PCI irqs.
2781 	 */
2782 	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2783 		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2784 		if (retval)
2785 			goto err_request_irq;
2786 	}
2787 
2788 	hcd->state = HC_STATE_RUNNING;
2789 	retval = hcd->driver->start(hcd);
2790 	if (retval < 0) {
2791 		dev_err(hcd->self.controller, "startup error %d\n", retval);
2792 		goto err_hcd_driver_start;
2793 	}
2794 
2795 	/* starting here, usbcore will pay attention to this root hub */
2796 	retval = register_root_hub(hcd);
2797 	if (retval != 0)
2798 		goto err_register_root_hub;
2799 
2800 	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2801 		usb_hcd_poll_rh_status(hcd);
2802 
2803 	return retval;
2804 
2805 err_register_root_hub:
2806 	hcd->rh_pollable = 0;
2807 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2808 	del_timer_sync(&hcd->rh_timer);
2809 	hcd->driver->stop(hcd);
2810 	hcd->state = HC_STATE_HALT;
2811 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2812 	del_timer_sync(&hcd->rh_timer);
2813 err_hcd_driver_start:
2814 	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2815 		free_irq(irqnum, hcd);
2816 err_request_irq:
2817 err_hcd_driver_setup:
2818 err_set_rh_speed:
2819 	usb_put_invalidate_rhdev(hcd);
2820 err_allocate_root_hub:
2821 	usb_deregister_bus(&hcd->self);
2822 err_register_bus:
2823 	hcd_buffer_destroy(hcd);
2824 err_create_buf:
2825 	usb_phy_roothub_power_off(hcd->phy_roothub);
2826 err_usb_phy_roothub_power_on:
2827 	usb_phy_roothub_exit(hcd->phy_roothub);
2828 
2829 	return retval;
2830 }
2831 EXPORT_SYMBOL_GPL(usb_add_hcd);
2832 
2833 /**
2834  * usb_remove_hcd - shutdown processing for generic HCDs
2835  * @hcd: the usb_hcd structure to remove
2836  * Context: !in_interrupt()
2837  *
2838  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2839  * invoking the HCD's stop() method.
2840  */
2841 void usb_remove_hcd(struct usb_hcd *hcd)
2842 {
2843 	struct usb_device *rhdev = hcd->self.root_hub;
2844 
2845 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2846 
2847 	usb_get_dev(rhdev);
2848 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2849 	if (HC_IS_RUNNING (hcd->state))
2850 		hcd->state = HC_STATE_QUIESCING;
2851 
2852 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2853 	spin_lock_irq (&hcd_root_hub_lock);
2854 	hcd->rh_registered = 0;
2855 	spin_unlock_irq (&hcd_root_hub_lock);
2856 
2857 #ifdef CONFIG_PM
2858 	cancel_work_sync(&hcd->wakeup_work);
2859 #endif
2860 	cancel_work_sync(&hcd->died_work);
2861 
2862 	mutex_lock(&usb_bus_idr_lock);
2863 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2864 	mutex_unlock(&usb_bus_idr_lock);
2865 
2866 	/*
2867 	 * tasklet_kill() isn't needed here because:
2868 	 * - driver's disconnect() called from usb_disconnect() should
2869 	 *   make sure its URBs are completed during the disconnect()
2870 	 *   callback
2871 	 *
2872 	 * - it is too late to run complete() here since driver may have
2873 	 *   been removed already now
2874 	 */
2875 
2876 	/* Prevent any more root-hub status calls from the timer.
2877 	 * The HCD might still restart the timer (if a port status change
2878 	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
2879 	 * the hub_status_data() callback.
2880 	 */
2881 	hcd->rh_pollable = 0;
2882 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2883 	del_timer_sync(&hcd->rh_timer);
2884 
2885 	hcd->driver->stop(hcd);
2886 	hcd->state = HC_STATE_HALT;
2887 
2888 	/* In case the HCD restarted the timer, stop it again. */
2889 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2890 	del_timer_sync(&hcd->rh_timer);
2891 
2892 	if (usb_hcd_is_primary_hcd(hcd)) {
2893 		if (hcd->irq > 0)
2894 			free_irq(hcd->irq, hcd);
2895 	}
2896 
2897 	usb_deregister_bus(&hcd->self);
2898 	hcd_buffer_destroy(hcd);
2899 
2900 	usb_phy_roothub_power_off(hcd->phy_roothub);
2901 	usb_phy_roothub_exit(hcd->phy_roothub);
2902 
2903 	usb_put_invalidate_rhdev(hcd);
2904 	hcd->flags = 0;
2905 }
2906 EXPORT_SYMBOL_GPL(usb_remove_hcd);
2907 
2908 void
2909 usb_hcd_platform_shutdown(struct platform_device *dev)
2910 {
2911 	struct usb_hcd *hcd = platform_get_drvdata(dev);
2912 
2913 	/* No need for pm_runtime_put(), we're shutting down */
2914 	pm_runtime_get_sync(&dev->dev);
2915 
2916 	if (hcd->driver->shutdown)
2917 		hcd->driver->shutdown(hcd);
2918 }
2919 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
2920 
2921 int usb_hcd_setup_local_mem(struct usb_hcd *hcd, phys_addr_t phys_addr,
2922 			    dma_addr_t dma, size_t size)
2923 {
2924 	int err;
2925 	void *local_mem;
2926 
2927 	hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, 4,
2928 						  dev_to_node(hcd->self.sysdev),
2929 						  dev_name(hcd->self.sysdev));
2930 	if (IS_ERR(hcd->localmem_pool))
2931 		return PTR_ERR(hcd->localmem_pool);
2932 
2933 	local_mem = devm_memremap(hcd->self.sysdev, phys_addr,
2934 				  size, MEMREMAP_WC);
2935 	if (IS_ERR(local_mem))
2936 		return PTR_ERR(local_mem);
2937 
2938 	/*
2939 	 * Here we pass a dma_addr_t but the arg type is a phys_addr_t.
2940 	 * It's not backed by system memory and thus there's no kernel mapping
2941 	 * for it.
2942 	 */
2943 	err = gen_pool_add_virt(hcd->localmem_pool, (unsigned long)local_mem,
2944 				dma, size, dev_to_node(hcd->self.sysdev));
2945 	if (err < 0) {
2946 		dev_err(hcd->self.sysdev, "gen_pool_add_virt failed with %d\n",
2947 			err);
2948 		return err;
2949 	}
2950 
2951 	return 0;
2952 }
2953 EXPORT_SYMBOL_GPL(usb_hcd_setup_local_mem);
2954 
2955 /*-------------------------------------------------------------------------*/
2956 
2957 #if IS_ENABLED(CONFIG_USB_MON)
2958 
2959 const struct usb_mon_operations *mon_ops;
2960 
2961 /*
2962  * The registration is unlocked.
2963  * We do it this way because we do not want to lock in hot paths.
2964  *
2965  * Notice that the code is minimally error-proof. Because usbmon needs
2966  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
2967  */
2968 
2969 int usb_mon_register(const struct usb_mon_operations *ops)
2970 {
2971 
2972 	if (mon_ops)
2973 		return -EBUSY;
2974 
2975 	mon_ops = ops;
2976 	mb();
2977 	return 0;
2978 }
2979 EXPORT_SYMBOL_GPL (usb_mon_register);
2980 
2981 void usb_mon_deregister (void)
2982 {
2983 
2984 	if (mon_ops == NULL) {
2985 		printk(KERN_ERR "USB: monitor was not registered\n");
2986 		return;
2987 	}
2988 	mon_ops = NULL;
2989 	mb();
2990 }
2991 EXPORT_SYMBOL_GPL (usb_mon_deregister);
2992 
2993 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
2994