xref: /openbmc/linux/drivers/usb/core/hcd.c (revision 31eeb6b0)
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 #include <linux/kcov.h>
35 
36 #include <linux/phy/phy.h>
37 #include <linux/usb.h>
38 #include <linux/usb/hcd.h>
39 #include <linux/usb/otg.h>
40 
41 #include "usb.h"
42 #include "phy.h"
43 
44 
45 /*-------------------------------------------------------------------------*/
46 
47 /*
48  * USB Host Controller Driver framework
49  *
50  * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
51  * HCD-specific behaviors/bugs.
52  *
53  * This does error checks, tracks devices and urbs, and delegates to a
54  * "hc_driver" only for code (and data) that really needs to know about
55  * hardware differences.  That includes root hub registers, i/o queues,
56  * and so on ... but as little else as possible.
57  *
58  * Shared code includes most of the "root hub" code (these are emulated,
59  * though each HC's hardware works differently) and PCI glue, plus request
60  * tracking overhead.  The HCD code should only block on spinlocks or on
61  * hardware handshaking; blocking on software events (such as other kernel
62  * threads releasing resources, or completing actions) is all generic.
63  *
64  * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
65  * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
66  * only by the hub driver ... and that neither should be seen or used by
67  * usb client device drivers.
68  *
69  * Contributors of ideas or unattributed patches include: David Brownell,
70  * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
71  *
72  * HISTORY:
73  * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
74  *		associated cleanup.  "usb_hcd" still != "usb_bus".
75  * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
76  */
77 
78 /*-------------------------------------------------------------------------*/
79 
80 /* Keep track of which host controller drivers are loaded */
81 unsigned long usb_hcds_loaded;
82 EXPORT_SYMBOL_GPL(usb_hcds_loaded);
83 
84 /* host controllers we manage */
85 DEFINE_IDR (usb_bus_idr);
86 EXPORT_SYMBOL_GPL (usb_bus_idr);
87 
88 /* used when allocating bus numbers */
89 #define USB_MAXBUS		64
90 
91 /* used when updating list of hcds */
92 DEFINE_MUTEX(usb_bus_idr_lock);	/* exported only for usbfs */
93 EXPORT_SYMBOL_GPL (usb_bus_idr_lock);
94 
95 /* used for controlling access to virtual root hubs */
96 static DEFINE_SPINLOCK(hcd_root_hub_lock);
97 
98 /* used when updating an endpoint's URB list */
99 static DEFINE_SPINLOCK(hcd_urb_list_lock);
100 
101 /* used to protect against unlinking URBs after the device is gone */
102 static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
103 
104 /* wait queue for synchronous unlinks */
105 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
106 
107 /*-------------------------------------------------------------------------*/
108 
109 /*
110  * Sharable chunks of root hub code.
111  */
112 
113 /*-------------------------------------------------------------------------*/
114 #define KERNEL_REL	bin2bcd(LINUX_VERSION_MAJOR)
115 #define KERNEL_VER	bin2bcd(LINUX_VERSION_PATCHLEVEL)
116 
117 /* usb 3.1 root hub device descriptor */
118 static const u8 usb31_rh_dev_descriptor[18] = {
119 	0x12,       /*  __u8  bLength; */
120 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
121 	0x10, 0x03, /*  __le16 bcdUSB; v3.1 */
122 
123 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
124 	0x00,	    /*  __u8  bDeviceSubClass; */
125 	0x03,       /*  __u8  bDeviceProtocol; USB 3 hub */
126 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
127 
128 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
129 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
130 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
131 
132 	0x03,       /*  __u8  iManufacturer; */
133 	0x02,       /*  __u8  iProduct; */
134 	0x01,       /*  __u8  iSerialNumber; */
135 	0x01        /*  __u8  bNumConfigurations; */
136 };
137 
138 /* usb 3.0 root hub device descriptor */
139 static const u8 usb3_rh_dev_descriptor[18] = {
140 	0x12,       /*  __u8  bLength; */
141 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
142 	0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
143 
144 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
145 	0x00,	    /*  __u8  bDeviceSubClass; */
146 	0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
147 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
148 
149 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
150 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
151 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
152 
153 	0x03,       /*  __u8  iManufacturer; */
154 	0x02,       /*  __u8  iProduct; */
155 	0x01,       /*  __u8  iSerialNumber; */
156 	0x01        /*  __u8  bNumConfigurations; */
157 };
158 
159 /* usb 2.5 (wireless USB 1.0) root hub device descriptor */
160 static const u8 usb25_rh_dev_descriptor[18] = {
161 	0x12,       /*  __u8  bLength; */
162 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
163 	0x50, 0x02, /*  __le16 bcdUSB; v2.5 */
164 
165 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
166 	0x00,	    /*  __u8  bDeviceSubClass; */
167 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
168 	0xFF,       /*  __u8  bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */
169 
170 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
171 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
172 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
173 
174 	0x03,       /*  __u8  iManufacturer; */
175 	0x02,       /*  __u8  iProduct; */
176 	0x01,       /*  __u8  iSerialNumber; */
177 	0x01        /*  __u8  bNumConfigurations; */
178 };
179 
180 /* usb 2.0 root hub device descriptor */
181 static const u8 usb2_rh_dev_descriptor[18] = {
182 	0x12,       /*  __u8  bLength; */
183 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
184 	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
185 
186 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
187 	0x00,	    /*  __u8  bDeviceSubClass; */
188 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
189 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
190 
191 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
192 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
193 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
194 
195 	0x03,       /*  __u8  iManufacturer; */
196 	0x02,       /*  __u8  iProduct; */
197 	0x01,       /*  __u8  iSerialNumber; */
198 	0x01        /*  __u8  bNumConfigurations; */
199 };
200 
201 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
202 
203 /* usb 1.1 root hub device descriptor */
204 static const u8 usb11_rh_dev_descriptor[18] = {
205 	0x12,       /*  __u8  bLength; */
206 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
207 	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
208 
209 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
210 	0x00,	    /*  __u8  bDeviceSubClass; */
211 	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
212 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
213 
214 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
215 	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
216 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
217 
218 	0x03,       /*  __u8  iManufacturer; */
219 	0x02,       /*  __u8  iProduct; */
220 	0x01,       /*  __u8  iSerialNumber; */
221 	0x01        /*  __u8  bNumConfigurations; */
222 };
223 
224 
225 /*-------------------------------------------------------------------------*/
226 
227 /* Configuration descriptors for our root hubs */
228 
229 static const u8 fs_rh_config_descriptor[] = {
230 
231 	/* one configuration */
232 	0x09,       /*  __u8  bLength; */
233 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
234 	0x19, 0x00, /*  __le16 wTotalLength; */
235 	0x01,       /*  __u8  bNumInterfaces; (1) */
236 	0x01,       /*  __u8  bConfigurationValue; */
237 	0x00,       /*  __u8  iConfiguration; */
238 	0xc0,       /*  __u8  bmAttributes;
239 				 Bit 7: must be set,
240 				     6: Self-powered,
241 				     5: Remote wakeup,
242 				     4..0: resvd */
243 	0x00,       /*  __u8  MaxPower; */
244 
245 	/* USB 1.1:
246 	 * USB 2.0, single TT organization (mandatory):
247 	 *	one interface, protocol 0
248 	 *
249 	 * USB 2.0, multiple TT organization (optional):
250 	 *	two interfaces, protocols 1 (like single TT)
251 	 *	and 2 (multiple TT mode) ... config is
252 	 *	sometimes settable
253 	 *	NOT IMPLEMENTED
254 	 */
255 
256 	/* one interface */
257 	0x09,       /*  __u8  if_bLength; */
258 	USB_DT_INTERFACE,  /* __u8 if_bDescriptorType; Interface */
259 	0x00,       /*  __u8  if_bInterfaceNumber; */
260 	0x00,       /*  __u8  if_bAlternateSetting; */
261 	0x01,       /*  __u8  if_bNumEndpoints; */
262 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
263 	0x00,       /*  __u8  if_bInterfaceSubClass; */
264 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
265 	0x00,       /*  __u8  if_iInterface; */
266 
267 	/* one endpoint (status change endpoint) */
268 	0x07,       /*  __u8  ep_bLength; */
269 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
270 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
271 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
272 	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
273 	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
274 };
275 
276 static const u8 hs_rh_config_descriptor[] = {
277 
278 	/* one configuration */
279 	0x09,       /*  __u8  bLength; */
280 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
281 	0x19, 0x00, /*  __le16 wTotalLength; */
282 	0x01,       /*  __u8  bNumInterfaces; (1) */
283 	0x01,       /*  __u8  bConfigurationValue; */
284 	0x00,       /*  __u8  iConfiguration; */
285 	0xc0,       /*  __u8  bmAttributes;
286 				 Bit 7: must be set,
287 				     6: Self-powered,
288 				     5: Remote wakeup,
289 				     4..0: resvd */
290 	0x00,       /*  __u8  MaxPower; */
291 
292 	/* USB 1.1:
293 	 * USB 2.0, single TT organization (mandatory):
294 	 *	one interface, protocol 0
295 	 *
296 	 * USB 2.0, multiple TT organization (optional):
297 	 *	two interfaces, protocols 1 (like single TT)
298 	 *	and 2 (multiple TT mode) ... config is
299 	 *	sometimes settable
300 	 *	NOT IMPLEMENTED
301 	 */
302 
303 	/* one interface */
304 	0x09,       /*  __u8  if_bLength; */
305 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
306 	0x00,       /*  __u8  if_bInterfaceNumber; */
307 	0x00,       /*  __u8  if_bAlternateSetting; */
308 	0x01,       /*  __u8  if_bNumEndpoints; */
309 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
310 	0x00,       /*  __u8  if_bInterfaceSubClass; */
311 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
312 	0x00,       /*  __u8  if_iInterface; */
313 
314 	/* one endpoint (status change endpoint) */
315 	0x07,       /*  __u8  ep_bLength; */
316 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
317 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
318 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
319 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
320 		     * see hub.c:hub_configure() for details. */
321 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
322 	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
323 };
324 
325 static const u8 ss_rh_config_descriptor[] = {
326 	/* one configuration */
327 	0x09,       /*  __u8  bLength; */
328 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
329 	0x1f, 0x00, /*  __le16 wTotalLength; */
330 	0x01,       /*  __u8  bNumInterfaces; (1) */
331 	0x01,       /*  __u8  bConfigurationValue; */
332 	0x00,       /*  __u8  iConfiguration; */
333 	0xc0,       /*  __u8  bmAttributes;
334 				 Bit 7: must be set,
335 				     6: Self-powered,
336 				     5: Remote wakeup,
337 				     4..0: resvd */
338 	0x00,       /*  __u8  MaxPower; */
339 
340 	/* one interface */
341 	0x09,       /*  __u8  if_bLength; */
342 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
343 	0x00,       /*  __u8  if_bInterfaceNumber; */
344 	0x00,       /*  __u8  if_bAlternateSetting; */
345 	0x01,       /*  __u8  if_bNumEndpoints; */
346 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
347 	0x00,       /*  __u8  if_bInterfaceSubClass; */
348 	0x00,       /*  __u8  if_bInterfaceProtocol; */
349 	0x00,       /*  __u8  if_iInterface; */
350 
351 	/* one endpoint (status change endpoint) */
352 	0x07,       /*  __u8  ep_bLength; */
353 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
354 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
355 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
356 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
357 		     * see hub.c:hub_configure() for details. */
358 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
359 	0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
360 
361 	/* one SuperSpeed endpoint companion descriptor */
362 	0x06,        /* __u8 ss_bLength */
363 	USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */
364 		     /* Companion */
365 	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
366 	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
367 	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
368 };
369 
370 /* authorized_default behaviour:
371  * -1 is authorized for all devices except wireless (old behaviour)
372  * 0 is unauthorized for all devices
373  * 1 is authorized for all devices
374  * 2 is authorized for internal devices
375  */
376 #define USB_AUTHORIZE_WIRED	-1
377 #define USB_AUTHORIZE_NONE	0
378 #define USB_AUTHORIZE_ALL	1
379 #define USB_AUTHORIZE_INTERNAL	2
380 
381 static int authorized_default = USB_AUTHORIZE_WIRED;
382 module_param(authorized_default, int, S_IRUGO|S_IWUSR);
383 MODULE_PARM_DESC(authorized_default,
384 		"Default USB device authorization: 0 is not authorized, 1 is "
385 		"authorized, 2 is authorized for internal devices, -1 is "
386 		"authorized except for wireless USB (default, old behaviour)");
387 /*-------------------------------------------------------------------------*/
388 
389 /**
390  * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
391  * @s: Null-terminated ASCII (actually ISO-8859-1) string
392  * @buf: Buffer for USB string descriptor (header + UTF-16LE)
393  * @len: Length (in bytes; may be odd) of descriptor buffer.
394  *
395  * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
396  * whichever is less.
397  *
398  * Note:
399  * USB String descriptors can contain at most 126 characters; input
400  * strings longer than that are truncated.
401  */
402 static unsigned
403 ascii2desc(char const *s, u8 *buf, unsigned len)
404 {
405 	unsigned n, t = 2 + 2*strlen(s);
406 
407 	if (t > 254)
408 		t = 254;	/* Longest possible UTF string descriptor */
409 	if (len > t)
410 		len = t;
411 
412 	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
413 
414 	n = len;
415 	while (n--) {
416 		*buf++ = t;
417 		if (!n--)
418 			break;
419 		*buf++ = t >> 8;
420 		t = (unsigned char)*s++;
421 	}
422 	return len;
423 }
424 
425 /**
426  * rh_string() - provides string descriptors for root hub
427  * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
428  * @hcd: the host controller for this root hub
429  * @data: buffer for output packet
430  * @len: length of the provided buffer
431  *
432  * Produces either a manufacturer, product or serial number string for the
433  * virtual root hub device.
434  *
435  * Return: The number of bytes filled in: the length of the descriptor or
436  * of the provided buffer, whichever is less.
437  */
438 static unsigned
439 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
440 {
441 	char buf[100];
442 	char const *s;
443 	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
444 
445 	/* language ids */
446 	switch (id) {
447 	case 0:
448 		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
449 		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
450 		if (len > 4)
451 			len = 4;
452 		memcpy(data, langids, len);
453 		return len;
454 	case 1:
455 		/* Serial number */
456 		s = hcd->self.bus_name;
457 		break;
458 	case 2:
459 		/* Product name */
460 		s = hcd->product_desc;
461 		break;
462 	case 3:
463 		/* Manufacturer */
464 		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
465 			init_utsname()->release, hcd->driver->description);
466 		s = buf;
467 		break;
468 	default:
469 		/* Can't happen; caller guarantees it */
470 		return 0;
471 	}
472 
473 	return ascii2desc(s, data, len);
474 }
475 
476 
477 /* Root hub control transfers execute synchronously */
478 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
479 {
480 	struct usb_ctrlrequest *cmd;
481 	u16		typeReq, wValue, wIndex, wLength;
482 	u8		*ubuf = urb->transfer_buffer;
483 	unsigned	len = 0;
484 	int		status;
485 	u8		patch_wakeup = 0;
486 	u8		patch_protocol = 0;
487 	u16		tbuf_size;
488 	u8		*tbuf = NULL;
489 	const u8	*bufp;
490 
491 	might_sleep();
492 
493 	spin_lock_irq(&hcd_root_hub_lock);
494 	status = usb_hcd_link_urb_to_ep(hcd, urb);
495 	spin_unlock_irq(&hcd_root_hub_lock);
496 	if (status)
497 		return status;
498 	urb->hcpriv = hcd;	/* Indicate it's queued */
499 
500 	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
501 	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
502 	wValue   = le16_to_cpu (cmd->wValue);
503 	wIndex   = le16_to_cpu (cmd->wIndex);
504 	wLength  = le16_to_cpu (cmd->wLength);
505 
506 	if (wLength > urb->transfer_buffer_length)
507 		goto error;
508 
509 	/*
510 	 * tbuf should be at least as big as the
511 	 * USB hub descriptor.
512 	 */
513 	tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
514 	tbuf = kzalloc(tbuf_size, GFP_KERNEL);
515 	if (!tbuf) {
516 		status = -ENOMEM;
517 		goto err_alloc;
518 	}
519 
520 	bufp = tbuf;
521 
522 
523 	urb->actual_length = 0;
524 	switch (typeReq) {
525 
526 	/* DEVICE REQUESTS */
527 
528 	/* The root hub's remote wakeup enable bit is implemented using
529 	 * driver model wakeup flags.  If this system supports wakeup
530 	 * through USB, userspace may change the default "allow wakeup"
531 	 * policy through sysfs or these calls.
532 	 *
533 	 * Most root hubs support wakeup from downstream devices, for
534 	 * runtime power management (disabling USB clocks and reducing
535 	 * VBUS power usage).  However, not all of them do so; silicon,
536 	 * board, and BIOS bugs here are not uncommon, so these can't
537 	 * be treated quite like external hubs.
538 	 *
539 	 * Likewise, not all root hubs will pass wakeup events upstream,
540 	 * to wake up the whole system.  So don't assume root hub and
541 	 * controller capabilities are identical.
542 	 */
543 
544 	case DeviceRequest | USB_REQ_GET_STATUS:
545 		tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
546 					<< USB_DEVICE_REMOTE_WAKEUP)
547 				| (1 << USB_DEVICE_SELF_POWERED);
548 		tbuf[1] = 0;
549 		len = 2;
550 		break;
551 	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
552 		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
553 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
554 		else
555 			goto error;
556 		break;
557 	case DeviceOutRequest | USB_REQ_SET_FEATURE:
558 		if (device_can_wakeup(&hcd->self.root_hub->dev)
559 				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
560 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
561 		else
562 			goto error;
563 		break;
564 	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
565 		tbuf[0] = 1;
566 		len = 1;
567 		fallthrough;
568 	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
569 		break;
570 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
571 		switch (wValue & 0xff00) {
572 		case USB_DT_DEVICE << 8:
573 			switch (hcd->speed) {
574 			case HCD_USB32:
575 			case HCD_USB31:
576 				bufp = usb31_rh_dev_descriptor;
577 				break;
578 			case HCD_USB3:
579 				bufp = usb3_rh_dev_descriptor;
580 				break;
581 			case HCD_USB25:
582 				bufp = usb25_rh_dev_descriptor;
583 				break;
584 			case HCD_USB2:
585 				bufp = usb2_rh_dev_descriptor;
586 				break;
587 			case HCD_USB11:
588 				bufp = usb11_rh_dev_descriptor;
589 				break;
590 			default:
591 				goto error;
592 			}
593 			len = 18;
594 			if (hcd->has_tt)
595 				patch_protocol = 1;
596 			break;
597 		case USB_DT_CONFIG << 8:
598 			switch (hcd->speed) {
599 			case HCD_USB32:
600 			case HCD_USB31:
601 			case HCD_USB3:
602 				bufp = ss_rh_config_descriptor;
603 				len = sizeof ss_rh_config_descriptor;
604 				break;
605 			case HCD_USB25:
606 			case HCD_USB2:
607 				bufp = hs_rh_config_descriptor;
608 				len = sizeof hs_rh_config_descriptor;
609 				break;
610 			case HCD_USB11:
611 				bufp = fs_rh_config_descriptor;
612 				len = sizeof fs_rh_config_descriptor;
613 				break;
614 			default:
615 				goto error;
616 			}
617 			if (device_can_wakeup(&hcd->self.root_hub->dev))
618 				patch_wakeup = 1;
619 			break;
620 		case USB_DT_STRING << 8:
621 			if ((wValue & 0xff) < 4)
622 				urb->actual_length = rh_string(wValue & 0xff,
623 						hcd, ubuf, wLength);
624 			else /* unsupported IDs --> "protocol stall" */
625 				goto error;
626 			break;
627 		case USB_DT_BOS << 8:
628 			goto nongeneric;
629 		default:
630 			goto error;
631 		}
632 		break;
633 	case DeviceRequest | USB_REQ_GET_INTERFACE:
634 		tbuf[0] = 0;
635 		len = 1;
636 		fallthrough;
637 	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
638 		break;
639 	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
640 		/* wValue == urb->dev->devaddr */
641 		dev_dbg (hcd->self.controller, "root hub device address %d\n",
642 			wValue);
643 		break;
644 
645 	/* INTERFACE REQUESTS (no defined feature/status flags) */
646 
647 	/* ENDPOINT REQUESTS */
648 
649 	case EndpointRequest | USB_REQ_GET_STATUS:
650 		/* ENDPOINT_HALT flag */
651 		tbuf[0] = 0;
652 		tbuf[1] = 0;
653 		len = 2;
654 		fallthrough;
655 	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
656 	case EndpointOutRequest | USB_REQ_SET_FEATURE:
657 		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
658 		break;
659 
660 	/* CLASS REQUESTS (and errors) */
661 
662 	default:
663 nongeneric:
664 		/* non-generic request */
665 		switch (typeReq) {
666 		case GetHubStatus:
667 			len = 4;
668 			break;
669 		case GetPortStatus:
670 			if (wValue == HUB_PORT_STATUS)
671 				len = 4;
672 			else
673 				/* other port status types return 8 bytes */
674 				len = 8;
675 			break;
676 		case GetHubDescriptor:
677 			len = sizeof (struct usb_hub_descriptor);
678 			break;
679 		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
680 			/* len is returned by hub_control */
681 			break;
682 		}
683 		status = hcd->driver->hub_control (hcd,
684 			typeReq, wValue, wIndex,
685 			tbuf, wLength);
686 
687 		if (typeReq == GetHubDescriptor)
688 			usb_hub_adjust_deviceremovable(hcd->self.root_hub,
689 				(struct usb_hub_descriptor *)tbuf);
690 		break;
691 error:
692 		/* "protocol stall" on error */
693 		status = -EPIPE;
694 	}
695 
696 	if (status < 0) {
697 		len = 0;
698 		if (status != -EPIPE) {
699 			dev_dbg (hcd->self.controller,
700 				"CTRL: TypeReq=0x%x val=0x%x "
701 				"idx=0x%x len=%d ==> %d\n",
702 				typeReq, wValue, wIndex,
703 				wLength, status);
704 		}
705 	} else if (status > 0) {
706 		/* hub_control may return the length of data copied. */
707 		len = status;
708 		status = 0;
709 	}
710 	if (len) {
711 		if (urb->transfer_buffer_length < len)
712 			len = urb->transfer_buffer_length;
713 		urb->actual_length = len;
714 		/* always USB_DIR_IN, toward host */
715 		memcpy (ubuf, bufp, len);
716 
717 		/* report whether RH hardware supports remote wakeup */
718 		if (patch_wakeup &&
719 				len > offsetof (struct usb_config_descriptor,
720 						bmAttributes))
721 			((struct usb_config_descriptor *)ubuf)->bmAttributes
722 				|= USB_CONFIG_ATT_WAKEUP;
723 
724 		/* report whether RH hardware has an integrated TT */
725 		if (patch_protocol &&
726 				len > offsetof(struct usb_device_descriptor,
727 						bDeviceProtocol))
728 			((struct usb_device_descriptor *) ubuf)->
729 				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
730 	}
731 
732 	kfree(tbuf);
733  err_alloc:
734 
735 	/* any errors get returned through the urb completion */
736 	spin_lock_irq(&hcd_root_hub_lock);
737 	usb_hcd_unlink_urb_from_ep(hcd, urb);
738 	usb_hcd_giveback_urb(hcd, urb, status);
739 	spin_unlock_irq(&hcd_root_hub_lock);
740 	return 0;
741 }
742 
743 /*-------------------------------------------------------------------------*/
744 
745 /*
746  * Root Hub interrupt transfers are polled using a timer if the
747  * driver requests it; otherwise the driver is responsible for
748  * calling usb_hcd_poll_rh_status() when an event occurs.
749  *
750  * Completion handler may not sleep. See usb_hcd_giveback_urb() for details.
751  */
752 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
753 {
754 	struct urb	*urb;
755 	int		length;
756 	int		status;
757 	unsigned long	flags;
758 	char		buffer[6];	/* Any root hubs with > 31 ports? */
759 
760 	if (unlikely(!hcd->rh_pollable))
761 		return;
762 	if (!hcd->uses_new_polling && !hcd->status_urb)
763 		return;
764 
765 	length = hcd->driver->hub_status_data(hcd, buffer);
766 	if (length > 0) {
767 
768 		/* try to complete the status urb */
769 		spin_lock_irqsave(&hcd_root_hub_lock, flags);
770 		urb = hcd->status_urb;
771 		if (urb) {
772 			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
773 			hcd->status_urb = NULL;
774 			if (urb->transfer_buffer_length >= length) {
775 				status = 0;
776 			} else {
777 				status = -EOVERFLOW;
778 				length = urb->transfer_buffer_length;
779 			}
780 			urb->actual_length = length;
781 			memcpy(urb->transfer_buffer, buffer, length);
782 
783 			usb_hcd_unlink_urb_from_ep(hcd, urb);
784 			usb_hcd_giveback_urb(hcd, urb, status);
785 		} else {
786 			length = 0;
787 			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
788 		}
789 		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
790 	}
791 
792 	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
793 	 * exceed that limit if HZ is 100. The math is more clunky than
794 	 * maybe expected, this is to make sure that all timers for USB devices
795 	 * fire at the same time to give the CPU a break in between */
796 	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
797 			(length == 0 && hcd->status_urb != NULL))
798 		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
799 }
800 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
801 
802 /* timer callback */
803 static void rh_timer_func (struct timer_list *t)
804 {
805 	struct usb_hcd *_hcd = from_timer(_hcd, t, rh_timer);
806 
807 	usb_hcd_poll_rh_status(_hcd);
808 }
809 
810 /*-------------------------------------------------------------------------*/
811 
812 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
813 {
814 	int		retval;
815 	unsigned long	flags;
816 	unsigned	len = 1 + (urb->dev->maxchild / 8);
817 
818 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
819 	if (hcd->status_urb || urb->transfer_buffer_length < len) {
820 		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
821 		retval = -EINVAL;
822 		goto done;
823 	}
824 
825 	retval = usb_hcd_link_urb_to_ep(hcd, urb);
826 	if (retval)
827 		goto done;
828 
829 	hcd->status_urb = urb;
830 	urb->hcpriv = hcd;	/* indicate it's queued */
831 	if (!hcd->uses_new_polling)
832 		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
833 
834 	/* If a status change has already occurred, report it ASAP */
835 	else if (HCD_POLL_PENDING(hcd))
836 		mod_timer(&hcd->rh_timer, jiffies);
837 	retval = 0;
838  done:
839 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
840 	return retval;
841 }
842 
843 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
844 {
845 	if (usb_endpoint_xfer_int(&urb->ep->desc))
846 		return rh_queue_status (hcd, urb);
847 	if (usb_endpoint_xfer_control(&urb->ep->desc))
848 		return rh_call_control (hcd, urb);
849 	return -EINVAL;
850 }
851 
852 /*-------------------------------------------------------------------------*/
853 
854 /* Unlinks of root-hub control URBs are legal, but they don't do anything
855  * since these URBs always execute synchronously.
856  */
857 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
858 {
859 	unsigned long	flags;
860 	int		rc;
861 
862 	spin_lock_irqsave(&hcd_root_hub_lock, flags);
863 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
864 	if (rc)
865 		goto done;
866 
867 	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
868 		;	/* Do nothing */
869 
870 	} else {				/* Status URB */
871 		if (!hcd->uses_new_polling)
872 			del_timer (&hcd->rh_timer);
873 		if (urb == hcd->status_urb) {
874 			hcd->status_urb = NULL;
875 			usb_hcd_unlink_urb_from_ep(hcd, urb);
876 			usb_hcd_giveback_urb(hcd, urb, status);
877 		}
878 	}
879  done:
880 	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
881 	return rc;
882 }
883 
884 
885 /*-------------------------------------------------------------------------*/
886 
887 /**
888  * usb_bus_init - shared initialization code
889  * @bus: the bus structure being initialized
890  *
891  * This code is used to initialize a usb_bus structure, memory for which is
892  * separately managed.
893  */
894 static void usb_bus_init (struct usb_bus *bus)
895 {
896 	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
897 
898 	bus->devnum_next = 1;
899 
900 	bus->root_hub = NULL;
901 	bus->busnum = -1;
902 	bus->bandwidth_allocated = 0;
903 	bus->bandwidth_int_reqs  = 0;
904 	bus->bandwidth_isoc_reqs = 0;
905 	mutex_init(&bus->devnum_next_mutex);
906 }
907 
908 /*-------------------------------------------------------------------------*/
909 
910 /**
911  * usb_register_bus - registers the USB host controller with the usb core
912  * @bus: pointer to the bus to register
913  *
914  * Context: task context, might sleep.
915  *
916  * Assigns a bus number, and links the controller into usbcore data
917  * structures so that it can be seen by scanning the bus list.
918  *
919  * Return: 0 if successful. A negative error code otherwise.
920  */
921 static int usb_register_bus(struct usb_bus *bus)
922 {
923 	int result = -E2BIG;
924 	int busnum;
925 
926 	mutex_lock(&usb_bus_idr_lock);
927 	busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL);
928 	if (busnum < 0) {
929 		pr_err("%s: failed to get bus number\n", usbcore_name);
930 		goto error_find_busnum;
931 	}
932 	bus->busnum = busnum;
933 	mutex_unlock(&usb_bus_idr_lock);
934 
935 	usb_notify_add_bus(bus);
936 
937 	dev_info (bus->controller, "new USB bus registered, assigned bus "
938 		  "number %d\n", bus->busnum);
939 	return 0;
940 
941 error_find_busnum:
942 	mutex_unlock(&usb_bus_idr_lock);
943 	return result;
944 }
945 
946 /**
947  * usb_deregister_bus - deregisters the USB host controller
948  * @bus: pointer to the bus to deregister
949  *
950  * Context: task context, might sleep.
951  *
952  * Recycles the bus number, and unlinks the controller from usbcore data
953  * structures so that it won't be seen by scanning the bus list.
954  */
955 static void usb_deregister_bus (struct usb_bus *bus)
956 {
957 	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
958 
959 	/*
960 	 * NOTE: make sure that all the devices are removed by the
961 	 * controller code, as well as having it call this when cleaning
962 	 * itself up
963 	 */
964 	mutex_lock(&usb_bus_idr_lock);
965 	idr_remove(&usb_bus_idr, bus->busnum);
966 	mutex_unlock(&usb_bus_idr_lock);
967 
968 	usb_notify_remove_bus(bus);
969 }
970 
971 /**
972  * register_root_hub - called by usb_add_hcd() to register a root hub
973  * @hcd: host controller for this root hub
974  *
975  * This function registers the root hub with the USB subsystem.  It sets up
976  * the device properly in the device tree and then calls usb_new_device()
977  * to register the usb device.  It also assigns the root hub's USB address
978  * (always 1).
979  *
980  * Return: 0 if successful. A negative error code otherwise.
981  */
982 static int register_root_hub(struct usb_hcd *hcd)
983 {
984 	struct device *parent_dev = hcd->self.controller;
985 	struct usb_device *usb_dev = hcd->self.root_hub;
986 	const int devnum = 1;
987 	int retval;
988 
989 	usb_dev->devnum = devnum;
990 	usb_dev->bus->devnum_next = devnum + 1;
991 	set_bit (devnum, usb_dev->bus->devmap.devicemap);
992 	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
993 
994 	mutex_lock(&usb_bus_idr_lock);
995 
996 	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
997 	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
998 	if (retval != sizeof usb_dev->descriptor) {
999 		mutex_unlock(&usb_bus_idr_lock);
1000 		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
1001 				dev_name(&usb_dev->dev), retval);
1002 		return (retval < 0) ? retval : -EMSGSIZE;
1003 	}
1004 
1005 	if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
1006 		retval = usb_get_bos_descriptor(usb_dev);
1007 		if (!retval) {
1008 			usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
1009 		} else if (usb_dev->speed >= USB_SPEED_SUPER) {
1010 			mutex_unlock(&usb_bus_idr_lock);
1011 			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1012 					dev_name(&usb_dev->dev), retval);
1013 			return retval;
1014 		}
1015 	}
1016 
1017 	retval = usb_new_device (usb_dev);
1018 	if (retval) {
1019 		dev_err (parent_dev, "can't register root hub for %s, %d\n",
1020 				dev_name(&usb_dev->dev), retval);
1021 	} else {
1022 		spin_lock_irq (&hcd_root_hub_lock);
1023 		hcd->rh_registered = 1;
1024 		spin_unlock_irq (&hcd_root_hub_lock);
1025 
1026 		/* Did the HC die before the root hub was registered? */
1027 		if (HCD_DEAD(hcd))
1028 			usb_hc_died (hcd);	/* This time clean up */
1029 	}
1030 	mutex_unlock(&usb_bus_idr_lock);
1031 
1032 	return retval;
1033 }
1034 
1035 /*
1036  * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1037  * @bus: the bus which the root hub belongs to
1038  * @portnum: the port which is being resumed
1039  *
1040  * HCDs should call this function when they know that a resume signal is
1041  * being sent to a root-hub port.  The root hub will be prevented from
1042  * going into autosuspend until usb_hcd_end_port_resume() is called.
1043  *
1044  * The bus's private lock must be held by the caller.
1045  */
1046 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1047 {
1048 	unsigned bit = 1 << portnum;
1049 
1050 	if (!(bus->resuming_ports & bit)) {
1051 		bus->resuming_ports |= bit;
1052 		pm_runtime_get_noresume(&bus->root_hub->dev);
1053 	}
1054 }
1055 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1056 
1057 /*
1058  * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1059  * @bus: the bus which the root hub belongs to
1060  * @portnum: the port which is being resumed
1061  *
1062  * HCDs should call this function when they know that a resume signal has
1063  * stopped being sent to a root-hub port.  The root hub will be allowed to
1064  * autosuspend again.
1065  *
1066  * The bus's private lock must be held by the caller.
1067  */
1068 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1069 {
1070 	unsigned bit = 1 << portnum;
1071 
1072 	if (bus->resuming_ports & bit) {
1073 		bus->resuming_ports &= ~bit;
1074 		pm_runtime_put_noidle(&bus->root_hub->dev);
1075 	}
1076 }
1077 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1078 
1079 /*-------------------------------------------------------------------------*/
1080 
1081 /**
1082  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1083  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1084  * @is_input: true iff the transaction sends data to the host
1085  * @isoc: true for isochronous transactions, false for interrupt ones
1086  * @bytecount: how many bytes in the transaction.
1087  *
1088  * Return: Approximate bus time in nanoseconds for a periodic transaction.
1089  *
1090  * Note:
1091  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1092  * scheduled in software, this function is only used for such scheduling.
1093  */
1094 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1095 {
1096 	unsigned long	tmp;
1097 
1098 	switch (speed) {
1099 	case USB_SPEED_LOW: 	/* INTR only */
1100 		if (is_input) {
1101 			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1102 			return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1103 		} else {
1104 			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1105 			return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1106 		}
1107 	case USB_SPEED_FULL:	/* ISOC or INTR */
1108 		if (isoc) {
1109 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1110 			return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1111 		} else {
1112 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1113 			return 9107L + BW_HOST_DELAY + tmp;
1114 		}
1115 	case USB_SPEED_HIGH:	/* ISOC or INTR */
1116 		/* FIXME adjust for input vs output */
1117 		if (isoc)
1118 			tmp = HS_NSECS_ISO (bytecount);
1119 		else
1120 			tmp = HS_NSECS (bytecount);
1121 		return tmp;
1122 	default:
1123 		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1124 		return -1;
1125 	}
1126 }
1127 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1128 
1129 
1130 /*-------------------------------------------------------------------------*/
1131 
1132 /*
1133  * Generic HC operations.
1134  */
1135 
1136 /*-------------------------------------------------------------------------*/
1137 
1138 /**
1139  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1140  * @hcd: host controller to which @urb was submitted
1141  * @urb: URB being submitted
1142  *
1143  * Host controller drivers should call this routine in their enqueue()
1144  * method.  The HCD's private spinlock must be held and interrupts must
1145  * be disabled.  The actions carried out here are required for URB
1146  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1147  *
1148  * Return: 0 for no error, otherwise a negative error code (in which case
1149  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1150  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1151  * the private spinlock and returning.
1152  */
1153 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1154 {
1155 	int		rc = 0;
1156 
1157 	spin_lock(&hcd_urb_list_lock);
1158 
1159 	/* Check that the URB isn't being killed */
1160 	if (unlikely(atomic_read(&urb->reject))) {
1161 		rc = -EPERM;
1162 		goto done;
1163 	}
1164 
1165 	if (unlikely(!urb->ep->enabled)) {
1166 		rc = -ENOENT;
1167 		goto done;
1168 	}
1169 
1170 	if (unlikely(!urb->dev->can_submit)) {
1171 		rc = -EHOSTUNREACH;
1172 		goto done;
1173 	}
1174 
1175 	/*
1176 	 * Check the host controller's state and add the URB to the
1177 	 * endpoint's queue.
1178 	 */
1179 	if (HCD_RH_RUNNING(hcd)) {
1180 		urb->unlinked = 0;
1181 		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1182 	} else {
1183 		rc = -ESHUTDOWN;
1184 		goto done;
1185 	}
1186  done:
1187 	spin_unlock(&hcd_urb_list_lock);
1188 	return rc;
1189 }
1190 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1191 
1192 /**
1193  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1194  * @hcd: host controller to which @urb was submitted
1195  * @urb: URB being checked for unlinkability
1196  * @status: error code to store in @urb if the unlink succeeds
1197  *
1198  * Host controller drivers should call this routine in their dequeue()
1199  * method.  The HCD's private spinlock must be held and interrupts must
1200  * be disabled.  The actions carried out here are required for making
1201  * sure than an unlink is valid.
1202  *
1203  * Return: 0 for no error, otherwise a negative error code (in which case
1204  * the dequeue() method must fail).  The possible error codes are:
1205  *
1206  *	-EIDRM: @urb was not submitted or has already completed.
1207  *		The completion function may not have been called yet.
1208  *
1209  *	-EBUSY: @urb has already been unlinked.
1210  */
1211 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1212 		int status)
1213 {
1214 	struct list_head	*tmp;
1215 
1216 	/* insist the urb is still queued */
1217 	list_for_each(tmp, &urb->ep->urb_list) {
1218 		if (tmp == &urb->urb_list)
1219 			break;
1220 	}
1221 	if (tmp != &urb->urb_list)
1222 		return -EIDRM;
1223 
1224 	/* Any status except -EINPROGRESS means something already started to
1225 	 * unlink this URB from the hardware.  So there's no more work to do.
1226 	 */
1227 	if (urb->unlinked)
1228 		return -EBUSY;
1229 	urb->unlinked = status;
1230 	return 0;
1231 }
1232 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1233 
1234 /**
1235  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1236  * @hcd: host controller to which @urb was submitted
1237  * @urb: URB being unlinked
1238  *
1239  * Host controller drivers should call this routine before calling
1240  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1241  * interrupts must be disabled.  The actions carried out here are required
1242  * for URB completion.
1243  */
1244 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1245 {
1246 	/* clear all state linking urb to this dev (and hcd) */
1247 	spin_lock(&hcd_urb_list_lock);
1248 	list_del_init(&urb->urb_list);
1249 	spin_unlock(&hcd_urb_list_lock);
1250 }
1251 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1252 
1253 /*
1254  * Some usb host controllers can only perform dma using a small SRAM area.
1255  * The usb core itself is however optimized for host controllers that can dma
1256  * using regular system memory - like pci devices doing bus mastering.
1257  *
1258  * To support host controllers with limited dma capabilities we provide dma
1259  * bounce buffers. This feature can be enabled by initializing
1260  * hcd->localmem_pool using usb_hcd_setup_local_mem().
1261  *
1262  * The initialized hcd->localmem_pool then tells the usb code to allocate all
1263  * data for dma using the genalloc API.
1264  *
1265  * So, to summarize...
1266  *
1267  * - We need "local" memory, canonical example being
1268  *   a small SRAM on a discrete controller being the
1269  *   only memory that the controller can read ...
1270  *   (a) "normal" kernel memory is no good, and
1271  *   (b) there's not enough to share
1272  *
1273  * - So we use that, even though the primary requirement
1274  *   is that the memory be "local" (hence addressable
1275  *   by that device), not "coherent".
1276  *
1277  */
1278 
1279 static int hcd_alloc_coherent(struct usb_bus *bus,
1280 			      gfp_t mem_flags, dma_addr_t *dma_handle,
1281 			      void **vaddr_handle, size_t size,
1282 			      enum dma_data_direction dir)
1283 {
1284 	unsigned char *vaddr;
1285 
1286 	if (*vaddr_handle == NULL) {
1287 		WARN_ON_ONCE(1);
1288 		return -EFAULT;
1289 	}
1290 
1291 	vaddr = hcd_buffer_alloc(bus, size + sizeof(unsigned long),
1292 				 mem_flags, dma_handle);
1293 	if (!vaddr)
1294 		return -ENOMEM;
1295 
1296 	/*
1297 	 * Store the virtual address of the buffer at the end
1298 	 * of the allocated dma buffer. The size of the buffer
1299 	 * may be uneven so use unaligned functions instead
1300 	 * of just rounding up. It makes sense to optimize for
1301 	 * memory footprint over access speed since the amount
1302 	 * of memory available for dma may be limited.
1303 	 */
1304 	put_unaligned((unsigned long)*vaddr_handle,
1305 		      (unsigned long *)(vaddr + size));
1306 
1307 	if (dir == DMA_TO_DEVICE)
1308 		memcpy(vaddr, *vaddr_handle, size);
1309 
1310 	*vaddr_handle = vaddr;
1311 	return 0;
1312 }
1313 
1314 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1315 			      void **vaddr_handle, size_t size,
1316 			      enum dma_data_direction dir)
1317 {
1318 	unsigned char *vaddr = *vaddr_handle;
1319 
1320 	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1321 
1322 	if (dir == DMA_FROM_DEVICE)
1323 		memcpy(vaddr, *vaddr_handle, size);
1324 
1325 	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1326 
1327 	*vaddr_handle = vaddr;
1328 	*dma_handle = 0;
1329 }
1330 
1331 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1332 {
1333 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1334 	    (urb->transfer_flags & URB_SETUP_MAP_SINGLE))
1335 		dma_unmap_single(hcd->self.sysdev,
1336 				urb->setup_dma,
1337 				sizeof(struct usb_ctrlrequest),
1338 				DMA_TO_DEVICE);
1339 	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1340 		hcd_free_coherent(urb->dev->bus,
1341 				&urb->setup_dma,
1342 				(void **) &urb->setup_packet,
1343 				sizeof(struct usb_ctrlrequest),
1344 				DMA_TO_DEVICE);
1345 
1346 	/* Make it safe to call this routine more than once */
1347 	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1348 }
1349 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1350 
1351 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1352 {
1353 	if (hcd->driver->unmap_urb_for_dma)
1354 		hcd->driver->unmap_urb_for_dma(hcd, urb);
1355 	else
1356 		usb_hcd_unmap_urb_for_dma(hcd, urb);
1357 }
1358 
1359 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1360 {
1361 	enum dma_data_direction dir;
1362 
1363 	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1364 
1365 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1366 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1367 	    (urb->transfer_flags & URB_DMA_MAP_SG))
1368 		dma_unmap_sg(hcd->self.sysdev,
1369 				urb->sg,
1370 				urb->num_sgs,
1371 				dir);
1372 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1373 		 (urb->transfer_flags & URB_DMA_MAP_PAGE))
1374 		dma_unmap_page(hcd->self.sysdev,
1375 				urb->transfer_dma,
1376 				urb->transfer_buffer_length,
1377 				dir);
1378 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1379 		 (urb->transfer_flags & URB_DMA_MAP_SINGLE))
1380 		dma_unmap_single(hcd->self.sysdev,
1381 				urb->transfer_dma,
1382 				urb->transfer_buffer_length,
1383 				dir);
1384 	else if (urb->transfer_flags & URB_MAP_LOCAL)
1385 		hcd_free_coherent(urb->dev->bus,
1386 				&urb->transfer_dma,
1387 				&urb->transfer_buffer,
1388 				urb->transfer_buffer_length,
1389 				dir);
1390 
1391 	/* Make it safe to call this routine more than once */
1392 	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1393 			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1394 }
1395 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1396 
1397 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1398 			   gfp_t mem_flags)
1399 {
1400 	if (hcd->driver->map_urb_for_dma)
1401 		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1402 	else
1403 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1404 }
1405 
1406 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1407 			    gfp_t mem_flags)
1408 {
1409 	enum dma_data_direction dir;
1410 	int ret = 0;
1411 
1412 	/* Map the URB's buffers for DMA access.
1413 	 * Lower level HCD code should use *_dma exclusively,
1414 	 * unless it uses pio or talks to another transport,
1415 	 * or uses the provided scatter gather list for bulk.
1416 	 */
1417 
1418 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1419 		if (hcd->self.uses_pio_for_control)
1420 			return ret;
1421 		if (hcd->localmem_pool) {
1422 			ret = hcd_alloc_coherent(
1423 					urb->dev->bus, mem_flags,
1424 					&urb->setup_dma,
1425 					(void **)&urb->setup_packet,
1426 					sizeof(struct usb_ctrlrequest),
1427 					DMA_TO_DEVICE);
1428 			if (ret)
1429 				return ret;
1430 			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1431 		} else if (hcd_uses_dma(hcd)) {
1432 			if (object_is_on_stack(urb->setup_packet)) {
1433 				WARN_ONCE(1, "setup packet is on stack\n");
1434 				return -EAGAIN;
1435 			}
1436 
1437 			urb->setup_dma = dma_map_single(
1438 					hcd->self.sysdev,
1439 					urb->setup_packet,
1440 					sizeof(struct usb_ctrlrequest),
1441 					DMA_TO_DEVICE);
1442 			if (dma_mapping_error(hcd->self.sysdev,
1443 						urb->setup_dma))
1444 				return -EAGAIN;
1445 			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1446 		}
1447 	}
1448 
1449 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1450 	if (urb->transfer_buffer_length != 0
1451 	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1452 		if (hcd->localmem_pool) {
1453 			ret = hcd_alloc_coherent(
1454 					urb->dev->bus, mem_flags,
1455 					&urb->transfer_dma,
1456 					&urb->transfer_buffer,
1457 					urb->transfer_buffer_length,
1458 					dir);
1459 			if (ret == 0)
1460 				urb->transfer_flags |= URB_MAP_LOCAL;
1461 		} else if (hcd_uses_dma(hcd)) {
1462 			if (urb->num_sgs) {
1463 				int n;
1464 
1465 				/* We don't support sg for isoc transfers ! */
1466 				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1467 					WARN_ON(1);
1468 					return -EINVAL;
1469 				}
1470 
1471 				n = dma_map_sg(
1472 						hcd->self.sysdev,
1473 						urb->sg,
1474 						urb->num_sgs,
1475 						dir);
1476 				if (n <= 0)
1477 					ret = -EAGAIN;
1478 				else
1479 					urb->transfer_flags |= URB_DMA_MAP_SG;
1480 				urb->num_mapped_sgs = n;
1481 				if (n != urb->num_sgs)
1482 					urb->transfer_flags |=
1483 							URB_DMA_SG_COMBINED;
1484 			} else if (urb->sg) {
1485 				struct scatterlist *sg = urb->sg;
1486 				urb->transfer_dma = dma_map_page(
1487 						hcd->self.sysdev,
1488 						sg_page(sg),
1489 						sg->offset,
1490 						urb->transfer_buffer_length,
1491 						dir);
1492 				if (dma_mapping_error(hcd->self.sysdev,
1493 						urb->transfer_dma))
1494 					ret = -EAGAIN;
1495 				else
1496 					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1497 			} else if (object_is_on_stack(urb->transfer_buffer)) {
1498 				WARN_ONCE(1, "transfer buffer is on stack\n");
1499 				ret = -EAGAIN;
1500 			} else {
1501 				urb->transfer_dma = dma_map_single(
1502 						hcd->self.sysdev,
1503 						urb->transfer_buffer,
1504 						urb->transfer_buffer_length,
1505 						dir);
1506 				if (dma_mapping_error(hcd->self.sysdev,
1507 						urb->transfer_dma))
1508 					ret = -EAGAIN;
1509 				else
1510 					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1511 			}
1512 		}
1513 		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1514 				URB_SETUP_MAP_LOCAL)))
1515 			usb_hcd_unmap_urb_for_dma(hcd, urb);
1516 	}
1517 	return ret;
1518 }
1519 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1520 
1521 /*-------------------------------------------------------------------------*/
1522 
1523 /* may be called in any context with a valid urb->dev usecount
1524  * caller surrenders "ownership" of urb
1525  * expects usb_submit_urb() to have sanity checked and conditioned all
1526  * inputs in the urb
1527  */
1528 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1529 {
1530 	int			status;
1531 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1532 
1533 	/* increment urb's reference count as part of giving it to the HCD
1534 	 * (which will control it).  HCD guarantees that it either returns
1535 	 * an error or calls giveback(), but not both.
1536 	 */
1537 	usb_get_urb(urb);
1538 	atomic_inc(&urb->use_count);
1539 	atomic_inc(&urb->dev->urbnum);
1540 	usbmon_urb_submit(&hcd->self, urb);
1541 
1542 	/* NOTE requirements on root-hub callers (usbfs and the hub
1543 	 * driver, for now):  URBs' urb->transfer_buffer must be
1544 	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1545 	 * they could clobber root hub response data.  Also, control
1546 	 * URBs must be submitted in process context with interrupts
1547 	 * enabled.
1548 	 */
1549 
1550 	if (is_root_hub(urb->dev)) {
1551 		status = rh_urb_enqueue(hcd, urb);
1552 	} else {
1553 		status = map_urb_for_dma(hcd, urb, mem_flags);
1554 		if (likely(status == 0)) {
1555 			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1556 			if (unlikely(status))
1557 				unmap_urb_for_dma(hcd, urb);
1558 		}
1559 	}
1560 
1561 	if (unlikely(status)) {
1562 		usbmon_urb_submit_error(&hcd->self, urb, status);
1563 		urb->hcpriv = NULL;
1564 		INIT_LIST_HEAD(&urb->urb_list);
1565 		atomic_dec(&urb->use_count);
1566 		atomic_dec(&urb->dev->urbnum);
1567 		if (atomic_read(&urb->reject))
1568 			wake_up(&usb_kill_urb_queue);
1569 		usb_put_urb(urb);
1570 	}
1571 	return status;
1572 }
1573 
1574 /*-------------------------------------------------------------------------*/
1575 
1576 /* this makes the hcd giveback() the urb more quickly, by kicking it
1577  * off hardware queues (which may take a while) and returning it as
1578  * soon as practical.  we've already set up the urb's return status,
1579  * but we can't know if the callback completed already.
1580  */
1581 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1582 {
1583 	int		value;
1584 
1585 	if (is_root_hub(urb->dev))
1586 		value = usb_rh_urb_dequeue(hcd, urb, status);
1587 	else {
1588 
1589 		/* The only reason an HCD might fail this call is if
1590 		 * it has not yet fully queued the urb to begin with.
1591 		 * Such failures should be harmless. */
1592 		value = hcd->driver->urb_dequeue(hcd, urb, status);
1593 	}
1594 	return value;
1595 }
1596 
1597 /*
1598  * called in any context
1599  *
1600  * caller guarantees urb won't be recycled till both unlink()
1601  * and the urb's completion function return
1602  */
1603 int usb_hcd_unlink_urb (struct urb *urb, int status)
1604 {
1605 	struct usb_hcd		*hcd;
1606 	struct usb_device	*udev = urb->dev;
1607 	int			retval = -EIDRM;
1608 	unsigned long		flags;
1609 
1610 	/* Prevent the device and bus from going away while
1611 	 * the unlink is carried out.  If they are already gone
1612 	 * then urb->use_count must be 0, since disconnected
1613 	 * devices can't have any active URBs.
1614 	 */
1615 	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1616 	if (atomic_read(&urb->use_count) > 0) {
1617 		retval = 0;
1618 		usb_get_dev(udev);
1619 	}
1620 	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1621 	if (retval == 0) {
1622 		hcd = bus_to_hcd(urb->dev->bus);
1623 		retval = unlink1(hcd, urb, status);
1624 		if (retval == 0)
1625 			retval = -EINPROGRESS;
1626 		else if (retval != -EIDRM && retval != -EBUSY)
1627 			dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n",
1628 					urb, retval);
1629 		usb_put_dev(udev);
1630 	}
1631 	return retval;
1632 }
1633 
1634 /*-------------------------------------------------------------------------*/
1635 
1636 static void __usb_hcd_giveback_urb(struct urb *urb)
1637 {
1638 	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1639 	struct usb_anchor *anchor = urb->anchor;
1640 	int status = urb->unlinked;
1641 
1642 	urb->hcpriv = NULL;
1643 	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1644 	    urb->actual_length < urb->transfer_buffer_length &&
1645 	    !status))
1646 		status = -EREMOTEIO;
1647 
1648 	unmap_urb_for_dma(hcd, urb);
1649 	usbmon_urb_complete(&hcd->self, urb, status);
1650 	usb_anchor_suspend_wakeups(anchor);
1651 	usb_unanchor_urb(urb);
1652 	if (likely(status == 0))
1653 		usb_led_activity(USB_LED_EVENT_HOST);
1654 
1655 	/* pass ownership to the completion handler */
1656 	urb->status = status;
1657 	/*
1658 	 * This function can be called in task context inside another remote
1659 	 * coverage collection section, but kcov doesn't support that kind of
1660 	 * recursion yet. Only collect coverage in softirq context for now.
1661 	 */
1662 	kcov_remote_start_usb_softirq((u64)urb->dev->bus->busnum);
1663 	urb->complete(urb);
1664 	kcov_remote_stop_softirq();
1665 
1666 	usb_anchor_resume_wakeups(anchor);
1667 	atomic_dec(&urb->use_count);
1668 	if (unlikely(atomic_read(&urb->reject)))
1669 		wake_up(&usb_kill_urb_queue);
1670 	usb_put_urb(urb);
1671 }
1672 
1673 static void usb_giveback_urb_bh(struct tasklet_struct *t)
1674 {
1675 	struct giveback_urb_bh *bh = from_tasklet(bh, t, bh);
1676 	struct list_head local_list;
1677 
1678 	spin_lock_irq(&bh->lock);
1679 	bh->running = true;
1680  restart:
1681 	list_replace_init(&bh->head, &local_list);
1682 	spin_unlock_irq(&bh->lock);
1683 
1684 	while (!list_empty(&local_list)) {
1685 		struct urb *urb;
1686 
1687 		urb = list_entry(local_list.next, struct urb, urb_list);
1688 		list_del_init(&urb->urb_list);
1689 		bh->completing_ep = urb->ep;
1690 		__usb_hcd_giveback_urb(urb);
1691 		bh->completing_ep = NULL;
1692 	}
1693 
1694 	/* check if there are new URBs to giveback */
1695 	spin_lock_irq(&bh->lock);
1696 	if (!list_empty(&bh->head))
1697 		goto restart;
1698 	bh->running = false;
1699 	spin_unlock_irq(&bh->lock);
1700 }
1701 
1702 /**
1703  * usb_hcd_giveback_urb - return URB from HCD to device driver
1704  * @hcd: host controller returning the URB
1705  * @urb: urb being returned to the USB device driver.
1706  * @status: completion status code for the URB.
1707  *
1708  * Context: atomic. The completion callback is invoked in caller's context.
1709  * For HCDs with HCD_BH flag set, the completion callback is invoked in tasklet
1710  * context (except for URBs submitted to the root hub which always complete in
1711  * caller's context).
1712  *
1713  * This hands the URB from HCD to its USB device driver, using its
1714  * completion function.  The HCD has freed all per-urb resources
1715  * (and is done using urb->hcpriv).  It also released all HCD locks;
1716  * the device driver won't cause problems if it frees, modifies,
1717  * or resubmits this URB.
1718  *
1719  * If @urb was unlinked, the value of @status will be overridden by
1720  * @urb->unlinked.  Erroneous short transfers are detected in case
1721  * the HCD hasn't checked for them.
1722  */
1723 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1724 {
1725 	struct giveback_urb_bh *bh;
1726 	bool running, high_prio_bh;
1727 
1728 	/* pass status to tasklet via unlinked */
1729 	if (likely(!urb->unlinked))
1730 		urb->unlinked = status;
1731 
1732 	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1733 		__usb_hcd_giveback_urb(urb);
1734 		return;
1735 	}
1736 
1737 	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
1738 		bh = &hcd->high_prio_bh;
1739 		high_prio_bh = true;
1740 	} else {
1741 		bh = &hcd->low_prio_bh;
1742 		high_prio_bh = false;
1743 	}
1744 
1745 	spin_lock(&bh->lock);
1746 	list_add_tail(&urb->urb_list, &bh->head);
1747 	running = bh->running;
1748 	spin_unlock(&bh->lock);
1749 
1750 	if (running)
1751 		;
1752 	else if (high_prio_bh)
1753 		tasklet_hi_schedule(&bh->bh);
1754 	else
1755 		tasklet_schedule(&bh->bh);
1756 }
1757 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1758 
1759 /*-------------------------------------------------------------------------*/
1760 
1761 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1762  * queue to drain completely.  The caller must first insure that no more
1763  * URBs can be submitted for this endpoint.
1764  */
1765 void usb_hcd_flush_endpoint(struct usb_device *udev,
1766 		struct usb_host_endpoint *ep)
1767 {
1768 	struct usb_hcd		*hcd;
1769 	struct urb		*urb;
1770 
1771 	if (!ep)
1772 		return;
1773 	might_sleep();
1774 	hcd = bus_to_hcd(udev->bus);
1775 
1776 	/* No more submits can occur */
1777 	spin_lock_irq(&hcd_urb_list_lock);
1778 rescan:
1779 	list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) {
1780 		int	is_in;
1781 
1782 		if (urb->unlinked)
1783 			continue;
1784 		usb_get_urb (urb);
1785 		is_in = usb_urb_dir_in(urb);
1786 		spin_unlock(&hcd_urb_list_lock);
1787 
1788 		/* kick hcd */
1789 		unlink1(hcd, urb, -ESHUTDOWN);
1790 		dev_dbg (hcd->self.controller,
1791 			"shutdown urb %pK ep%d%s-%s\n",
1792 			urb, usb_endpoint_num(&ep->desc),
1793 			is_in ? "in" : "out",
1794 			usb_ep_type_string(usb_endpoint_type(&ep->desc)));
1795 		usb_put_urb (urb);
1796 
1797 		/* list contents may have changed */
1798 		spin_lock(&hcd_urb_list_lock);
1799 		goto rescan;
1800 	}
1801 	spin_unlock_irq(&hcd_urb_list_lock);
1802 
1803 	/* Wait until the endpoint queue is completely empty */
1804 	while (!list_empty (&ep->urb_list)) {
1805 		spin_lock_irq(&hcd_urb_list_lock);
1806 
1807 		/* The list may have changed while we acquired the spinlock */
1808 		urb = NULL;
1809 		if (!list_empty (&ep->urb_list)) {
1810 			urb = list_entry (ep->urb_list.prev, struct urb,
1811 					urb_list);
1812 			usb_get_urb (urb);
1813 		}
1814 		spin_unlock_irq(&hcd_urb_list_lock);
1815 
1816 		if (urb) {
1817 			usb_kill_urb (urb);
1818 			usb_put_urb (urb);
1819 		}
1820 	}
1821 }
1822 
1823 /**
1824  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1825  *				the bus bandwidth
1826  * @udev: target &usb_device
1827  * @new_config: new configuration to install
1828  * @cur_alt: the current alternate interface setting
1829  * @new_alt: alternate interface setting that is being installed
1830  *
1831  * To change configurations, pass in the new configuration in new_config,
1832  * and pass NULL for cur_alt and new_alt.
1833  *
1834  * To reset a device's configuration (put the device in the ADDRESSED state),
1835  * pass in NULL for new_config, cur_alt, and new_alt.
1836  *
1837  * To change alternate interface settings, pass in NULL for new_config,
1838  * pass in the current alternate interface setting in cur_alt,
1839  * and pass in the new alternate interface setting in new_alt.
1840  *
1841  * Return: An error if the requested bandwidth change exceeds the
1842  * bus bandwidth or host controller internal resources.
1843  */
1844 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1845 		struct usb_host_config *new_config,
1846 		struct usb_host_interface *cur_alt,
1847 		struct usb_host_interface *new_alt)
1848 {
1849 	int num_intfs, i, j;
1850 	struct usb_host_interface *alt = NULL;
1851 	int ret = 0;
1852 	struct usb_hcd *hcd;
1853 	struct usb_host_endpoint *ep;
1854 
1855 	hcd = bus_to_hcd(udev->bus);
1856 	if (!hcd->driver->check_bandwidth)
1857 		return 0;
1858 
1859 	/* Configuration is being removed - set configuration 0 */
1860 	if (!new_config && !cur_alt) {
1861 		for (i = 1; i < 16; ++i) {
1862 			ep = udev->ep_out[i];
1863 			if (ep)
1864 				hcd->driver->drop_endpoint(hcd, udev, ep);
1865 			ep = udev->ep_in[i];
1866 			if (ep)
1867 				hcd->driver->drop_endpoint(hcd, udev, ep);
1868 		}
1869 		hcd->driver->check_bandwidth(hcd, udev);
1870 		return 0;
1871 	}
1872 	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1873 	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1874 	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1875 	 * ok to exclude it.
1876 	 */
1877 	if (new_config) {
1878 		num_intfs = new_config->desc.bNumInterfaces;
1879 		/* Remove endpoints (except endpoint 0, which is always on the
1880 		 * schedule) from the old config from the schedule
1881 		 */
1882 		for (i = 1; i < 16; ++i) {
1883 			ep = udev->ep_out[i];
1884 			if (ep) {
1885 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1886 				if (ret < 0)
1887 					goto reset;
1888 			}
1889 			ep = udev->ep_in[i];
1890 			if (ep) {
1891 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1892 				if (ret < 0)
1893 					goto reset;
1894 			}
1895 		}
1896 		for (i = 0; i < num_intfs; ++i) {
1897 			struct usb_host_interface *first_alt;
1898 			int iface_num;
1899 
1900 			first_alt = &new_config->intf_cache[i]->altsetting[0];
1901 			iface_num = first_alt->desc.bInterfaceNumber;
1902 			/* Set up endpoints for alternate interface setting 0 */
1903 			alt = usb_find_alt_setting(new_config, iface_num, 0);
1904 			if (!alt)
1905 				/* No alt setting 0? Pick the first setting. */
1906 				alt = first_alt;
1907 
1908 			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1909 				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1910 				if (ret < 0)
1911 					goto reset;
1912 			}
1913 		}
1914 	}
1915 	if (cur_alt && new_alt) {
1916 		struct usb_interface *iface = usb_ifnum_to_if(udev,
1917 				cur_alt->desc.bInterfaceNumber);
1918 
1919 		if (!iface)
1920 			return -EINVAL;
1921 		if (iface->resetting_device) {
1922 			/*
1923 			 * The USB core just reset the device, so the xHCI host
1924 			 * and the device will think alt setting 0 is installed.
1925 			 * However, the USB core will pass in the alternate
1926 			 * setting installed before the reset as cur_alt.  Dig
1927 			 * out the alternate setting 0 structure, or the first
1928 			 * alternate setting if a broken device doesn't have alt
1929 			 * setting 0.
1930 			 */
1931 			cur_alt = usb_altnum_to_altsetting(iface, 0);
1932 			if (!cur_alt)
1933 				cur_alt = &iface->altsetting[0];
1934 		}
1935 
1936 		/* Drop all the endpoints in the current alt setting */
1937 		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
1938 			ret = hcd->driver->drop_endpoint(hcd, udev,
1939 					&cur_alt->endpoint[i]);
1940 			if (ret < 0)
1941 				goto reset;
1942 		}
1943 		/* Add all the endpoints in the new alt setting */
1944 		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
1945 			ret = hcd->driver->add_endpoint(hcd, udev,
1946 					&new_alt->endpoint[i]);
1947 			if (ret < 0)
1948 				goto reset;
1949 		}
1950 	}
1951 	ret = hcd->driver->check_bandwidth(hcd, udev);
1952 reset:
1953 	if (ret < 0)
1954 		hcd->driver->reset_bandwidth(hcd, udev);
1955 	return ret;
1956 }
1957 
1958 /* Disables the endpoint: synchronizes with the hcd to make sure all
1959  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
1960  * have been called previously.  Use for set_configuration, set_interface,
1961  * driver removal, physical disconnect.
1962  *
1963  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
1964  * type, maxpacket size, toggle, halt status, and scheduling.
1965  */
1966 void usb_hcd_disable_endpoint(struct usb_device *udev,
1967 		struct usb_host_endpoint *ep)
1968 {
1969 	struct usb_hcd		*hcd;
1970 
1971 	might_sleep();
1972 	hcd = bus_to_hcd(udev->bus);
1973 	if (hcd->driver->endpoint_disable)
1974 		hcd->driver->endpoint_disable(hcd, ep);
1975 }
1976 
1977 /**
1978  * usb_hcd_reset_endpoint - reset host endpoint state
1979  * @udev: USB device.
1980  * @ep:   the endpoint to reset.
1981  *
1982  * Resets any host endpoint state such as the toggle bit, sequence
1983  * number and current window.
1984  */
1985 void usb_hcd_reset_endpoint(struct usb_device *udev,
1986 			    struct usb_host_endpoint *ep)
1987 {
1988 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1989 
1990 	if (hcd->driver->endpoint_reset)
1991 		hcd->driver->endpoint_reset(hcd, ep);
1992 	else {
1993 		int epnum = usb_endpoint_num(&ep->desc);
1994 		int is_out = usb_endpoint_dir_out(&ep->desc);
1995 		int is_control = usb_endpoint_xfer_control(&ep->desc);
1996 
1997 		usb_settoggle(udev, epnum, is_out, 0);
1998 		if (is_control)
1999 			usb_settoggle(udev, epnum, !is_out, 0);
2000 	}
2001 }
2002 
2003 /**
2004  * usb_alloc_streams - allocate bulk endpoint stream IDs.
2005  * @interface:		alternate setting that includes all endpoints.
2006  * @eps:		array of endpoints that need streams.
2007  * @num_eps:		number of endpoints in the array.
2008  * @num_streams:	number of streams to allocate.
2009  * @mem_flags:		flags hcd should use to allocate memory.
2010  *
2011  * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
2012  * Drivers may queue multiple transfers to different stream IDs, which may
2013  * complete in a different order than they were queued.
2014  *
2015  * Return: On success, the number of allocated streams. On failure, a negative
2016  * error code.
2017  */
2018 int usb_alloc_streams(struct usb_interface *interface,
2019 		struct usb_host_endpoint **eps, unsigned int num_eps,
2020 		unsigned int num_streams, gfp_t mem_flags)
2021 {
2022 	struct usb_hcd *hcd;
2023 	struct usb_device *dev;
2024 	int i, ret;
2025 
2026 	dev = interface_to_usbdev(interface);
2027 	hcd = bus_to_hcd(dev->bus);
2028 	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2029 		return -EINVAL;
2030 	if (dev->speed < USB_SPEED_SUPER)
2031 		return -EINVAL;
2032 	if (dev->state < USB_STATE_CONFIGURED)
2033 		return -ENODEV;
2034 
2035 	for (i = 0; i < num_eps; i++) {
2036 		/* Streams only apply to bulk endpoints. */
2037 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2038 			return -EINVAL;
2039 		/* Re-alloc is not allowed */
2040 		if (eps[i]->streams)
2041 			return -EINVAL;
2042 	}
2043 
2044 	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2045 			num_streams, mem_flags);
2046 	if (ret < 0)
2047 		return ret;
2048 
2049 	for (i = 0; i < num_eps; i++)
2050 		eps[i]->streams = ret;
2051 
2052 	return ret;
2053 }
2054 EXPORT_SYMBOL_GPL(usb_alloc_streams);
2055 
2056 /**
2057  * usb_free_streams - free bulk endpoint stream IDs.
2058  * @interface:	alternate setting that includes all endpoints.
2059  * @eps:	array of endpoints to remove streams from.
2060  * @num_eps:	number of endpoints in the array.
2061  * @mem_flags:	flags hcd should use to allocate memory.
2062  *
2063  * Reverts a group of bulk endpoints back to not using stream IDs.
2064  * Can fail if we are given bad arguments, or HCD is broken.
2065  *
2066  * Return: 0 on success. On failure, a negative error code.
2067  */
2068 int usb_free_streams(struct usb_interface *interface,
2069 		struct usb_host_endpoint **eps, unsigned int num_eps,
2070 		gfp_t mem_flags)
2071 {
2072 	struct usb_hcd *hcd;
2073 	struct usb_device *dev;
2074 	int i, ret;
2075 
2076 	dev = interface_to_usbdev(interface);
2077 	hcd = bus_to_hcd(dev->bus);
2078 	if (dev->speed < USB_SPEED_SUPER)
2079 		return -EINVAL;
2080 
2081 	/* Double-free is not allowed */
2082 	for (i = 0; i < num_eps; i++)
2083 		if (!eps[i] || !eps[i]->streams)
2084 			return -EINVAL;
2085 
2086 	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2087 	if (ret < 0)
2088 		return ret;
2089 
2090 	for (i = 0; i < num_eps; i++)
2091 		eps[i]->streams = 0;
2092 
2093 	return ret;
2094 }
2095 EXPORT_SYMBOL_GPL(usb_free_streams);
2096 
2097 /* Protect against drivers that try to unlink URBs after the device
2098  * is gone, by waiting until all unlinks for @udev are finished.
2099  * Since we don't currently track URBs by device, simply wait until
2100  * nothing is running in the locked region of usb_hcd_unlink_urb().
2101  */
2102 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2103 {
2104 	spin_lock_irq(&hcd_urb_unlink_lock);
2105 	spin_unlock_irq(&hcd_urb_unlink_lock);
2106 }
2107 
2108 /*-------------------------------------------------------------------------*/
2109 
2110 /* called in any context */
2111 int usb_hcd_get_frame_number (struct usb_device *udev)
2112 {
2113 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
2114 
2115 	if (!HCD_RH_RUNNING(hcd))
2116 		return -ESHUTDOWN;
2117 	return hcd->driver->get_frame_number (hcd);
2118 }
2119 
2120 /*-------------------------------------------------------------------------*/
2121 #ifdef CONFIG_USB_HCD_TEST_MODE
2122 
2123 static void usb_ehset_completion(struct urb *urb)
2124 {
2125 	struct completion  *done = urb->context;
2126 
2127 	complete(done);
2128 }
2129 /*
2130  * Allocate and initialize a control URB. This request will be used by the
2131  * EHSET SINGLE_STEP_SET_FEATURE test in which the DATA and STATUS stages
2132  * of the GetDescriptor request are sent 15 seconds after the SETUP stage.
2133  * Return NULL if failed.
2134  */
2135 static struct urb *request_single_step_set_feature_urb(
2136 	struct usb_device	*udev,
2137 	void			*dr,
2138 	void			*buf,
2139 	struct completion	*done)
2140 {
2141 	struct urb *urb;
2142 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2143 	struct usb_host_endpoint *ep;
2144 
2145 	urb = usb_alloc_urb(0, GFP_KERNEL);
2146 	if (!urb)
2147 		return NULL;
2148 
2149 	urb->pipe = usb_rcvctrlpipe(udev, 0);
2150 	ep = (usb_pipein(urb->pipe) ? udev->ep_in : udev->ep_out)
2151 				[usb_pipeendpoint(urb->pipe)];
2152 	if (!ep) {
2153 		usb_free_urb(urb);
2154 		return NULL;
2155 	}
2156 
2157 	urb->ep = ep;
2158 	urb->dev = udev;
2159 	urb->setup_packet = (void *)dr;
2160 	urb->transfer_buffer = buf;
2161 	urb->transfer_buffer_length = USB_DT_DEVICE_SIZE;
2162 	urb->complete = usb_ehset_completion;
2163 	urb->status = -EINPROGRESS;
2164 	urb->actual_length = 0;
2165 	urb->transfer_flags = URB_DIR_IN;
2166 	usb_get_urb(urb);
2167 	atomic_inc(&urb->use_count);
2168 	atomic_inc(&urb->dev->urbnum);
2169 	if (map_urb_for_dma(hcd, urb, GFP_KERNEL)) {
2170 		usb_put_urb(urb);
2171 		usb_free_urb(urb);
2172 		return NULL;
2173 	}
2174 
2175 	urb->context = done;
2176 	return urb;
2177 }
2178 
2179 int ehset_single_step_set_feature(struct usb_hcd *hcd, int port)
2180 {
2181 	int retval = -ENOMEM;
2182 	struct usb_ctrlrequest *dr;
2183 	struct urb *urb;
2184 	struct usb_device *udev;
2185 	struct usb_device_descriptor *buf;
2186 	DECLARE_COMPLETION_ONSTACK(done);
2187 
2188 	/* Obtain udev of the rhub's child port */
2189 	udev = usb_hub_find_child(hcd->self.root_hub, port);
2190 	if (!udev) {
2191 		dev_err(hcd->self.controller, "No device attached to the RootHub\n");
2192 		return -ENODEV;
2193 	}
2194 	buf = kmalloc(USB_DT_DEVICE_SIZE, GFP_KERNEL);
2195 	if (!buf)
2196 		return -ENOMEM;
2197 
2198 	dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
2199 	if (!dr) {
2200 		kfree(buf);
2201 		return -ENOMEM;
2202 	}
2203 
2204 	/* Fill Setup packet for GetDescriptor */
2205 	dr->bRequestType = USB_DIR_IN;
2206 	dr->bRequest = USB_REQ_GET_DESCRIPTOR;
2207 	dr->wValue = cpu_to_le16(USB_DT_DEVICE << 8);
2208 	dr->wIndex = 0;
2209 	dr->wLength = cpu_to_le16(USB_DT_DEVICE_SIZE);
2210 	urb = request_single_step_set_feature_urb(udev, dr, buf, &done);
2211 	if (!urb)
2212 		goto cleanup;
2213 
2214 	/* Submit just the SETUP stage */
2215 	retval = hcd->driver->submit_single_step_set_feature(hcd, urb, 1);
2216 	if (retval)
2217 		goto out1;
2218 	if (!wait_for_completion_timeout(&done, msecs_to_jiffies(2000))) {
2219 		usb_kill_urb(urb);
2220 		retval = -ETIMEDOUT;
2221 		dev_err(hcd->self.controller,
2222 			"%s SETUP stage timed out on ep0\n", __func__);
2223 		goto out1;
2224 	}
2225 	msleep(15 * 1000);
2226 
2227 	/* Complete remaining DATA and STATUS stages using the same URB */
2228 	urb->status = -EINPROGRESS;
2229 	usb_get_urb(urb);
2230 	atomic_inc(&urb->use_count);
2231 	atomic_inc(&urb->dev->urbnum);
2232 	retval = hcd->driver->submit_single_step_set_feature(hcd, urb, 0);
2233 	if (!retval && !wait_for_completion_timeout(&done,
2234 						msecs_to_jiffies(2000))) {
2235 		usb_kill_urb(urb);
2236 		retval = -ETIMEDOUT;
2237 		dev_err(hcd->self.controller,
2238 			"%s IN stage timed out on ep0\n", __func__);
2239 	}
2240 out1:
2241 	usb_free_urb(urb);
2242 cleanup:
2243 	kfree(dr);
2244 	kfree(buf);
2245 	return retval;
2246 }
2247 EXPORT_SYMBOL_GPL(ehset_single_step_set_feature);
2248 #endif /* CONFIG_USB_HCD_TEST_MODE */
2249 
2250 /*-------------------------------------------------------------------------*/
2251 
2252 #ifdef	CONFIG_PM
2253 
2254 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2255 {
2256 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2257 	int		status;
2258 	int		old_state = hcd->state;
2259 
2260 	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2261 			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2262 			rhdev->do_remote_wakeup);
2263 	if (HCD_DEAD(hcd)) {
2264 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2265 		return 0;
2266 	}
2267 
2268 	if (!hcd->driver->bus_suspend) {
2269 		status = -ENOENT;
2270 	} else {
2271 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2272 		hcd->state = HC_STATE_QUIESCING;
2273 		status = hcd->driver->bus_suspend(hcd);
2274 	}
2275 	if (status == 0) {
2276 		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2277 		hcd->state = HC_STATE_SUSPENDED;
2278 
2279 		if (!PMSG_IS_AUTO(msg))
2280 			usb_phy_roothub_suspend(hcd->self.sysdev,
2281 						hcd->phy_roothub);
2282 
2283 		/* Did we race with a root-hub wakeup event? */
2284 		if (rhdev->do_remote_wakeup) {
2285 			char	buffer[6];
2286 
2287 			status = hcd->driver->hub_status_data(hcd, buffer);
2288 			if (status != 0) {
2289 				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2290 				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2291 				status = -EBUSY;
2292 			}
2293 		}
2294 	} else {
2295 		spin_lock_irq(&hcd_root_hub_lock);
2296 		if (!HCD_DEAD(hcd)) {
2297 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2298 			hcd->state = old_state;
2299 		}
2300 		spin_unlock_irq(&hcd_root_hub_lock);
2301 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2302 				"suspend", status);
2303 	}
2304 	return status;
2305 }
2306 
2307 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2308 {
2309 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2310 	int		status;
2311 	int		old_state = hcd->state;
2312 
2313 	dev_dbg(&rhdev->dev, "usb %sresume\n",
2314 			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2315 	if (HCD_DEAD(hcd)) {
2316 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2317 		return 0;
2318 	}
2319 
2320 	if (!PMSG_IS_AUTO(msg)) {
2321 		status = usb_phy_roothub_resume(hcd->self.sysdev,
2322 						hcd->phy_roothub);
2323 		if (status)
2324 			return status;
2325 	}
2326 
2327 	if (!hcd->driver->bus_resume)
2328 		return -ENOENT;
2329 	if (HCD_RH_RUNNING(hcd))
2330 		return 0;
2331 
2332 	hcd->state = HC_STATE_RESUMING;
2333 	status = hcd->driver->bus_resume(hcd);
2334 	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2335 	if (status == 0)
2336 		status = usb_phy_roothub_calibrate(hcd->phy_roothub);
2337 
2338 	if (status == 0) {
2339 		struct usb_device *udev;
2340 		int port1;
2341 
2342 		spin_lock_irq(&hcd_root_hub_lock);
2343 		if (!HCD_DEAD(hcd)) {
2344 			usb_set_device_state(rhdev, rhdev->actconfig
2345 					? USB_STATE_CONFIGURED
2346 					: USB_STATE_ADDRESS);
2347 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2348 			hcd->state = HC_STATE_RUNNING;
2349 		}
2350 		spin_unlock_irq(&hcd_root_hub_lock);
2351 
2352 		/*
2353 		 * Check whether any of the enabled ports on the root hub are
2354 		 * unsuspended.  If they are then a TRSMRCY delay is needed
2355 		 * (this is what the USB-2 spec calls a "global resume").
2356 		 * Otherwise we can skip the delay.
2357 		 */
2358 		usb_hub_for_each_child(rhdev, port1, udev) {
2359 			if (udev->state != USB_STATE_NOTATTACHED &&
2360 					!udev->port_is_suspended) {
2361 				usleep_range(10000, 11000);	/* TRSMRCY */
2362 				break;
2363 			}
2364 		}
2365 	} else {
2366 		hcd->state = old_state;
2367 		usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub);
2368 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2369 				"resume", status);
2370 		if (status != -ESHUTDOWN)
2371 			usb_hc_died(hcd);
2372 	}
2373 	return status;
2374 }
2375 
2376 /* Workqueue routine for root-hub remote wakeup */
2377 static void hcd_resume_work(struct work_struct *work)
2378 {
2379 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2380 	struct usb_device *udev = hcd->self.root_hub;
2381 
2382 	usb_remote_wakeup(udev);
2383 }
2384 
2385 /**
2386  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2387  * @hcd: host controller for this root hub
2388  *
2389  * The USB host controller calls this function when its root hub is
2390  * suspended (with the remote wakeup feature enabled) and a remote
2391  * wakeup request is received.  The routine submits a workqueue request
2392  * to resume the root hub (that is, manage its downstream ports again).
2393  */
2394 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2395 {
2396 	unsigned long flags;
2397 
2398 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2399 	if (hcd->rh_registered) {
2400 		pm_wakeup_event(&hcd->self.root_hub->dev, 0);
2401 		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2402 		queue_work(pm_wq, &hcd->wakeup_work);
2403 	}
2404 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2405 }
2406 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2407 
2408 #endif	/* CONFIG_PM */
2409 
2410 /*-------------------------------------------------------------------------*/
2411 
2412 #ifdef	CONFIG_USB_OTG
2413 
2414 /**
2415  * usb_bus_start_enum - start immediate enumeration (for OTG)
2416  * @bus: the bus (must use hcd framework)
2417  * @port_num: 1-based number of port; usually bus->otg_port
2418  * Context: atomic
2419  *
2420  * Starts enumeration, with an immediate reset followed later by
2421  * hub_wq identifying and possibly configuring the device.
2422  * This is needed by OTG controller drivers, where it helps meet
2423  * HNP protocol timing requirements for starting a port reset.
2424  *
2425  * Return: 0 if successful.
2426  */
2427 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2428 {
2429 	struct usb_hcd		*hcd;
2430 	int			status = -EOPNOTSUPP;
2431 
2432 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2433 	 * boards with root hubs hooked up to internal devices (instead of
2434 	 * just the OTG port) may need more attention to resetting...
2435 	 */
2436 	hcd = bus_to_hcd(bus);
2437 	if (port_num && hcd->driver->start_port_reset)
2438 		status = hcd->driver->start_port_reset(hcd, port_num);
2439 
2440 	/* allocate hub_wq shortly after (first) root port reset finishes;
2441 	 * it may issue others, until at least 50 msecs have passed.
2442 	 */
2443 	if (status == 0)
2444 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2445 	return status;
2446 }
2447 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2448 
2449 #endif
2450 
2451 /*-------------------------------------------------------------------------*/
2452 
2453 /**
2454  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2455  * @irq: the IRQ being raised
2456  * @__hcd: pointer to the HCD whose IRQ is being signaled
2457  *
2458  * If the controller isn't HALTed, calls the driver's irq handler.
2459  * Checks whether the controller is now dead.
2460  *
2461  * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2462  */
2463 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2464 {
2465 	struct usb_hcd		*hcd = __hcd;
2466 	irqreturn_t		rc;
2467 
2468 	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2469 		rc = IRQ_NONE;
2470 	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2471 		rc = IRQ_NONE;
2472 	else
2473 		rc = IRQ_HANDLED;
2474 
2475 	return rc;
2476 }
2477 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2478 
2479 /*-------------------------------------------------------------------------*/
2480 
2481 /* Workqueue routine for when the root-hub has died. */
2482 static void hcd_died_work(struct work_struct *work)
2483 {
2484 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, died_work);
2485 	static char *env[] = {
2486 		"ERROR=DEAD",
2487 		NULL
2488 	};
2489 
2490 	/* Notify user space that the host controller has died */
2491 	kobject_uevent_env(&hcd->self.root_hub->dev.kobj, KOBJ_OFFLINE, env);
2492 }
2493 
2494 /**
2495  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2496  * @hcd: pointer to the HCD representing the controller
2497  *
2498  * This is called by bus glue to report a USB host controller that died
2499  * while operations may still have been pending.  It's called automatically
2500  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2501  *
2502  * Only call this function with the primary HCD.
2503  */
2504 void usb_hc_died (struct usb_hcd *hcd)
2505 {
2506 	unsigned long flags;
2507 
2508 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2509 
2510 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2511 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2512 	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2513 	if (hcd->rh_registered) {
2514 		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2515 
2516 		/* make hub_wq clean up old urbs and devices */
2517 		usb_set_device_state (hcd->self.root_hub,
2518 				USB_STATE_NOTATTACHED);
2519 		usb_kick_hub_wq(hcd->self.root_hub);
2520 	}
2521 	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2522 		hcd = hcd->shared_hcd;
2523 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2524 		set_bit(HCD_FLAG_DEAD, &hcd->flags);
2525 		if (hcd->rh_registered) {
2526 			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2527 
2528 			/* make hub_wq clean up old urbs and devices */
2529 			usb_set_device_state(hcd->self.root_hub,
2530 					USB_STATE_NOTATTACHED);
2531 			usb_kick_hub_wq(hcd->self.root_hub);
2532 		}
2533 	}
2534 
2535 	/* Handle the case where this function gets called with a shared HCD */
2536 	if (usb_hcd_is_primary_hcd(hcd))
2537 		schedule_work(&hcd->died_work);
2538 	else
2539 		schedule_work(&hcd->primary_hcd->died_work);
2540 
2541 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2542 	/* Make sure that the other roothub is also deallocated. */
2543 }
2544 EXPORT_SYMBOL_GPL (usb_hc_died);
2545 
2546 /*-------------------------------------------------------------------------*/
2547 
2548 static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2549 {
2550 
2551 	spin_lock_init(&bh->lock);
2552 	INIT_LIST_HEAD(&bh->head);
2553 	tasklet_setup(&bh->bh, usb_giveback_urb_bh);
2554 }
2555 
2556 struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
2557 		struct device *sysdev, struct device *dev, const char *bus_name,
2558 		struct usb_hcd *primary_hcd)
2559 {
2560 	struct usb_hcd *hcd;
2561 
2562 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2563 	if (!hcd)
2564 		return NULL;
2565 	if (primary_hcd == NULL) {
2566 		hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex),
2567 				GFP_KERNEL);
2568 		if (!hcd->address0_mutex) {
2569 			kfree(hcd);
2570 			dev_dbg(dev, "hcd address0 mutex alloc failed\n");
2571 			return NULL;
2572 		}
2573 		mutex_init(hcd->address0_mutex);
2574 		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2575 				GFP_KERNEL);
2576 		if (!hcd->bandwidth_mutex) {
2577 			kfree(hcd->address0_mutex);
2578 			kfree(hcd);
2579 			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2580 			return NULL;
2581 		}
2582 		mutex_init(hcd->bandwidth_mutex);
2583 		dev_set_drvdata(dev, hcd);
2584 	} else {
2585 		mutex_lock(&usb_port_peer_mutex);
2586 		hcd->address0_mutex = primary_hcd->address0_mutex;
2587 		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2588 		hcd->primary_hcd = primary_hcd;
2589 		primary_hcd->primary_hcd = primary_hcd;
2590 		hcd->shared_hcd = primary_hcd;
2591 		primary_hcd->shared_hcd = hcd;
2592 		mutex_unlock(&usb_port_peer_mutex);
2593 	}
2594 
2595 	kref_init(&hcd->kref);
2596 
2597 	usb_bus_init(&hcd->self);
2598 	hcd->self.controller = dev;
2599 	hcd->self.sysdev = sysdev;
2600 	hcd->self.bus_name = bus_name;
2601 
2602 	timer_setup(&hcd->rh_timer, rh_timer_func, 0);
2603 #ifdef CONFIG_PM
2604 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2605 #endif
2606 
2607 	INIT_WORK(&hcd->died_work, hcd_died_work);
2608 
2609 	hcd->driver = driver;
2610 	hcd->speed = driver->flags & HCD_MASK;
2611 	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2612 			"USB Host Controller";
2613 	return hcd;
2614 }
2615 EXPORT_SYMBOL_GPL(__usb_create_hcd);
2616 
2617 /**
2618  * usb_create_shared_hcd - create and initialize an HCD structure
2619  * @driver: HC driver that will use this hcd
2620  * @dev: device for this HC, stored in hcd->self.controller
2621  * @bus_name: value to store in hcd->self.bus_name
2622  * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2623  *              PCI device.  Only allocate certain resources for the primary HCD
2624  *
2625  * Context: task context, might sleep.
2626  *
2627  * Allocate a struct usb_hcd, with extra space at the end for the
2628  * HC driver's private data.  Initialize the generic members of the
2629  * hcd structure.
2630  *
2631  * Return: On success, a pointer to the created and initialized HCD structure.
2632  * On failure (e.g. if memory is unavailable), %NULL.
2633  */
2634 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2635 		struct device *dev, const char *bus_name,
2636 		struct usb_hcd *primary_hcd)
2637 {
2638 	return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd);
2639 }
2640 EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2641 
2642 /**
2643  * usb_create_hcd - create and initialize an HCD structure
2644  * @driver: HC driver that will use this hcd
2645  * @dev: device for this HC, stored in hcd->self.controller
2646  * @bus_name: value to store in hcd->self.bus_name
2647  *
2648  * Context: task context, might sleep.
2649  *
2650  * Allocate a struct usb_hcd, with extra space at the end for the
2651  * HC driver's private data.  Initialize the generic members of the
2652  * hcd structure.
2653  *
2654  * Return: On success, a pointer to the created and initialized HCD
2655  * structure. On failure (e.g. if memory is unavailable), %NULL.
2656  */
2657 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2658 		struct device *dev, const char *bus_name)
2659 {
2660 	return __usb_create_hcd(driver, dev, dev, bus_name, NULL);
2661 }
2662 EXPORT_SYMBOL_GPL(usb_create_hcd);
2663 
2664 /*
2665  * Roothubs that share one PCI device must also share the bandwidth mutex.
2666  * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2667  * deallocated.
2668  *
2669  * Make sure to deallocate the bandwidth_mutex only when the last HCD is
2670  * freed.  When hcd_release() is called for either hcd in a peer set,
2671  * invalidate the peer's ->shared_hcd and ->primary_hcd pointers.
2672  */
2673 static void hcd_release(struct kref *kref)
2674 {
2675 	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2676 
2677 	mutex_lock(&usb_port_peer_mutex);
2678 	if (hcd->shared_hcd) {
2679 		struct usb_hcd *peer = hcd->shared_hcd;
2680 
2681 		peer->shared_hcd = NULL;
2682 		peer->primary_hcd = NULL;
2683 	} else {
2684 		kfree(hcd->address0_mutex);
2685 		kfree(hcd->bandwidth_mutex);
2686 	}
2687 	mutex_unlock(&usb_port_peer_mutex);
2688 	kfree(hcd);
2689 }
2690 
2691 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2692 {
2693 	if (hcd)
2694 		kref_get (&hcd->kref);
2695 	return hcd;
2696 }
2697 EXPORT_SYMBOL_GPL(usb_get_hcd);
2698 
2699 void usb_put_hcd (struct usb_hcd *hcd)
2700 {
2701 	if (hcd)
2702 		kref_put (&hcd->kref, hcd_release);
2703 }
2704 EXPORT_SYMBOL_GPL(usb_put_hcd);
2705 
2706 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2707 {
2708 	if (!hcd->primary_hcd)
2709 		return 1;
2710 	return hcd == hcd->primary_hcd;
2711 }
2712 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2713 
2714 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2715 {
2716 	if (!hcd->driver->find_raw_port_number)
2717 		return port1;
2718 
2719 	return hcd->driver->find_raw_port_number(hcd, port1);
2720 }
2721 
2722 static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2723 		unsigned int irqnum, unsigned long irqflags)
2724 {
2725 	int retval;
2726 
2727 	if (hcd->driver->irq) {
2728 
2729 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2730 				hcd->driver->description, hcd->self.busnum);
2731 		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2732 				hcd->irq_descr, hcd);
2733 		if (retval != 0) {
2734 			dev_err(hcd->self.controller,
2735 					"request interrupt %d failed\n",
2736 					irqnum);
2737 			return retval;
2738 		}
2739 		hcd->irq = irqnum;
2740 		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2741 				(hcd->driver->flags & HCD_MEMORY) ?
2742 					"io mem" : "io port",
2743 				(unsigned long long)hcd->rsrc_start);
2744 	} else {
2745 		hcd->irq = 0;
2746 		if (hcd->rsrc_start)
2747 			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2748 					(hcd->driver->flags & HCD_MEMORY) ?
2749 						"io mem" : "io port",
2750 					(unsigned long long)hcd->rsrc_start);
2751 	}
2752 	return 0;
2753 }
2754 
2755 /*
2756  * Before we free this root hub, flush in-flight peering attempts
2757  * and disable peer lookups
2758  */
2759 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2760 {
2761 	struct usb_device *rhdev;
2762 
2763 	mutex_lock(&usb_port_peer_mutex);
2764 	rhdev = hcd->self.root_hub;
2765 	hcd->self.root_hub = NULL;
2766 	mutex_unlock(&usb_port_peer_mutex);
2767 	usb_put_dev(rhdev);
2768 }
2769 
2770 /**
2771  * usb_stop_hcd - Halt the HCD
2772  * @hcd: the usb_hcd that has to be halted
2773  *
2774  * Stop the root-hub polling timer and invoke the HCD's ->stop callback.
2775  */
2776 static void usb_stop_hcd(struct usb_hcd *hcd)
2777 {
2778 	hcd->rh_pollable = 0;
2779 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2780 	del_timer_sync(&hcd->rh_timer);
2781 
2782 	hcd->driver->stop(hcd);
2783 	hcd->state = HC_STATE_HALT;
2784 
2785 	/* In case the HCD restarted the timer, stop it again. */
2786 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2787 	del_timer_sync(&hcd->rh_timer);
2788 }
2789 
2790 /**
2791  * usb_add_hcd - finish generic HCD structure initialization and register
2792  * @hcd: the usb_hcd structure to initialize
2793  * @irqnum: Interrupt line to allocate
2794  * @irqflags: Interrupt type flags
2795  *
2796  * Finish the remaining parts of generic HCD initialization: allocate the
2797  * buffers of consistent memory, register the bus, request the IRQ line,
2798  * and call the driver's reset() and start() routines.
2799  */
2800 int usb_add_hcd(struct usb_hcd *hcd,
2801 		unsigned int irqnum, unsigned long irqflags)
2802 {
2803 	int retval;
2804 	struct usb_device *rhdev;
2805 
2806 	if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) {
2807 		hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev);
2808 		if (IS_ERR(hcd->phy_roothub))
2809 			return PTR_ERR(hcd->phy_roothub);
2810 
2811 		retval = usb_phy_roothub_init(hcd->phy_roothub);
2812 		if (retval)
2813 			return retval;
2814 
2815 		retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2816 						  PHY_MODE_USB_HOST_SS);
2817 		if (retval)
2818 			retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2819 							  PHY_MODE_USB_HOST);
2820 		if (retval)
2821 			goto err_usb_phy_roothub_power_on;
2822 
2823 		retval = usb_phy_roothub_power_on(hcd->phy_roothub);
2824 		if (retval)
2825 			goto err_usb_phy_roothub_power_on;
2826 	}
2827 
2828 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2829 
2830 	switch (authorized_default) {
2831 	case USB_AUTHORIZE_NONE:
2832 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_NONE;
2833 		break;
2834 
2835 	case USB_AUTHORIZE_ALL:
2836 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_ALL;
2837 		break;
2838 
2839 	case USB_AUTHORIZE_INTERNAL:
2840 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_INTERNAL;
2841 		break;
2842 
2843 	case USB_AUTHORIZE_WIRED:
2844 	default:
2845 		hcd->dev_policy = hcd->wireless ?
2846 			USB_DEVICE_AUTHORIZE_NONE : USB_DEVICE_AUTHORIZE_ALL;
2847 		break;
2848 	}
2849 
2850 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2851 
2852 	/* per default all interfaces are authorized */
2853 	set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
2854 
2855 	/* HC is in reset state, but accessible.  Now do the one-time init,
2856 	 * bottom up so that hcds can customize the root hubs before hub_wq
2857 	 * starts talking to them.  (Note, bus id is assigned early too.)
2858 	 */
2859 	retval = hcd_buffer_create(hcd);
2860 	if (retval != 0) {
2861 		dev_dbg(hcd->self.sysdev, "pool alloc failed\n");
2862 		goto err_create_buf;
2863 	}
2864 
2865 	retval = usb_register_bus(&hcd->self);
2866 	if (retval < 0)
2867 		goto err_register_bus;
2868 
2869 	rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2870 	if (rhdev == NULL) {
2871 		dev_err(hcd->self.sysdev, "unable to allocate root hub\n");
2872 		retval = -ENOMEM;
2873 		goto err_allocate_root_hub;
2874 	}
2875 	mutex_lock(&usb_port_peer_mutex);
2876 	hcd->self.root_hub = rhdev;
2877 	mutex_unlock(&usb_port_peer_mutex);
2878 
2879 	rhdev->rx_lanes = 1;
2880 	rhdev->tx_lanes = 1;
2881 	rhdev->ssp_rate = USB_SSP_GEN_UNKNOWN;
2882 
2883 	switch (hcd->speed) {
2884 	case HCD_USB11:
2885 		rhdev->speed = USB_SPEED_FULL;
2886 		break;
2887 	case HCD_USB2:
2888 		rhdev->speed = USB_SPEED_HIGH;
2889 		break;
2890 	case HCD_USB25:
2891 		rhdev->speed = USB_SPEED_WIRELESS;
2892 		break;
2893 	case HCD_USB3:
2894 		rhdev->speed = USB_SPEED_SUPER;
2895 		break;
2896 	case HCD_USB32:
2897 		rhdev->rx_lanes = 2;
2898 		rhdev->tx_lanes = 2;
2899 		rhdev->ssp_rate = USB_SSP_GEN_2x2;
2900 		rhdev->speed = USB_SPEED_SUPER_PLUS;
2901 		break;
2902 	case HCD_USB31:
2903 		rhdev->ssp_rate = USB_SSP_GEN_2x1;
2904 		rhdev->speed = USB_SPEED_SUPER_PLUS;
2905 		break;
2906 	default:
2907 		retval = -EINVAL;
2908 		goto err_set_rh_speed;
2909 	}
2910 
2911 	/* wakeup flag init defaults to "everything works" for root hubs,
2912 	 * but drivers can override it in reset() if needed, along with
2913 	 * recording the overall controller's system wakeup capability.
2914 	 */
2915 	device_set_wakeup_capable(&rhdev->dev, 1);
2916 
2917 	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2918 	 * registered.  But since the controller can die at any time,
2919 	 * let's initialize the flag before touching the hardware.
2920 	 */
2921 	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2922 
2923 	/* "reset" is misnamed; its role is now one-time init. the controller
2924 	 * should already have been reset (and boot firmware kicked off etc).
2925 	 */
2926 	if (hcd->driver->reset) {
2927 		retval = hcd->driver->reset(hcd);
2928 		if (retval < 0) {
2929 			dev_err(hcd->self.controller, "can't setup: %d\n",
2930 					retval);
2931 			goto err_hcd_driver_setup;
2932 		}
2933 	}
2934 	hcd->rh_pollable = 1;
2935 
2936 	retval = usb_phy_roothub_calibrate(hcd->phy_roothub);
2937 	if (retval)
2938 		goto err_hcd_driver_setup;
2939 
2940 	/* NOTE: root hub and controller capabilities may not be the same */
2941 	if (device_can_wakeup(hcd->self.controller)
2942 			&& device_can_wakeup(&hcd->self.root_hub->dev))
2943 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2944 
2945 	/* initialize tasklets */
2946 	init_giveback_urb_bh(&hcd->high_prio_bh);
2947 	init_giveback_urb_bh(&hcd->low_prio_bh);
2948 
2949 	/* enable irqs just before we start the controller,
2950 	 * if the BIOS provides legacy PCI irqs.
2951 	 */
2952 	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2953 		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2954 		if (retval)
2955 			goto err_request_irq;
2956 	}
2957 
2958 	hcd->state = HC_STATE_RUNNING;
2959 	retval = hcd->driver->start(hcd);
2960 	if (retval < 0) {
2961 		dev_err(hcd->self.controller, "startup error %d\n", retval);
2962 		goto err_hcd_driver_start;
2963 	}
2964 
2965 	/* starting here, usbcore will pay attention to this root hub */
2966 	retval = register_root_hub(hcd);
2967 	if (retval != 0)
2968 		goto err_register_root_hub;
2969 
2970 	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2971 		usb_hcd_poll_rh_status(hcd);
2972 
2973 	return retval;
2974 
2975 err_register_root_hub:
2976 	usb_stop_hcd(hcd);
2977 err_hcd_driver_start:
2978 	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2979 		free_irq(irqnum, hcd);
2980 err_request_irq:
2981 err_hcd_driver_setup:
2982 err_set_rh_speed:
2983 	usb_put_invalidate_rhdev(hcd);
2984 err_allocate_root_hub:
2985 	usb_deregister_bus(&hcd->self);
2986 err_register_bus:
2987 	hcd_buffer_destroy(hcd);
2988 err_create_buf:
2989 	usb_phy_roothub_power_off(hcd->phy_roothub);
2990 err_usb_phy_roothub_power_on:
2991 	usb_phy_roothub_exit(hcd->phy_roothub);
2992 
2993 	return retval;
2994 }
2995 EXPORT_SYMBOL_GPL(usb_add_hcd);
2996 
2997 /**
2998  * usb_remove_hcd - shutdown processing for generic HCDs
2999  * @hcd: the usb_hcd structure to remove
3000  *
3001  * Context: task context, might sleep.
3002  *
3003  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
3004  * invoking the HCD's stop() method.
3005  */
3006 void usb_remove_hcd(struct usb_hcd *hcd)
3007 {
3008 	struct usb_device *rhdev = hcd->self.root_hub;
3009 
3010 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
3011 
3012 	usb_get_dev(rhdev);
3013 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
3014 	if (HC_IS_RUNNING (hcd->state))
3015 		hcd->state = HC_STATE_QUIESCING;
3016 
3017 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
3018 	spin_lock_irq (&hcd_root_hub_lock);
3019 	hcd->rh_registered = 0;
3020 	spin_unlock_irq (&hcd_root_hub_lock);
3021 
3022 #ifdef CONFIG_PM
3023 	cancel_work_sync(&hcd->wakeup_work);
3024 #endif
3025 	cancel_work_sync(&hcd->died_work);
3026 
3027 	mutex_lock(&usb_bus_idr_lock);
3028 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
3029 	mutex_unlock(&usb_bus_idr_lock);
3030 
3031 	/*
3032 	 * tasklet_kill() isn't needed here because:
3033 	 * - driver's disconnect() called from usb_disconnect() should
3034 	 *   make sure its URBs are completed during the disconnect()
3035 	 *   callback
3036 	 *
3037 	 * - it is too late to run complete() here since driver may have
3038 	 *   been removed already now
3039 	 */
3040 
3041 	/* Prevent any more root-hub status calls from the timer.
3042 	 * The HCD might still restart the timer (if a port status change
3043 	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
3044 	 * the hub_status_data() callback.
3045 	 */
3046 	usb_stop_hcd(hcd);
3047 
3048 	if (usb_hcd_is_primary_hcd(hcd)) {
3049 		if (hcd->irq > 0)
3050 			free_irq(hcd->irq, hcd);
3051 	}
3052 
3053 	usb_deregister_bus(&hcd->self);
3054 	hcd_buffer_destroy(hcd);
3055 
3056 	usb_phy_roothub_power_off(hcd->phy_roothub);
3057 	usb_phy_roothub_exit(hcd->phy_roothub);
3058 
3059 	usb_put_invalidate_rhdev(hcd);
3060 	hcd->flags = 0;
3061 }
3062 EXPORT_SYMBOL_GPL(usb_remove_hcd);
3063 
3064 void
3065 usb_hcd_platform_shutdown(struct platform_device *dev)
3066 {
3067 	struct usb_hcd *hcd = platform_get_drvdata(dev);
3068 
3069 	/* No need for pm_runtime_put(), we're shutting down */
3070 	pm_runtime_get_sync(&dev->dev);
3071 
3072 	if (hcd->driver->shutdown)
3073 		hcd->driver->shutdown(hcd);
3074 }
3075 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
3076 
3077 int usb_hcd_setup_local_mem(struct usb_hcd *hcd, phys_addr_t phys_addr,
3078 			    dma_addr_t dma, size_t size)
3079 {
3080 	int err;
3081 	void *local_mem;
3082 
3083 	hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, 4,
3084 						  dev_to_node(hcd->self.sysdev),
3085 						  dev_name(hcd->self.sysdev));
3086 	if (IS_ERR(hcd->localmem_pool))
3087 		return PTR_ERR(hcd->localmem_pool);
3088 
3089 	local_mem = devm_memremap(hcd->self.sysdev, phys_addr,
3090 				  size, MEMREMAP_WC);
3091 	if (IS_ERR(local_mem))
3092 		return PTR_ERR(local_mem);
3093 
3094 	/*
3095 	 * Here we pass a dma_addr_t but the arg type is a phys_addr_t.
3096 	 * It's not backed by system memory and thus there's no kernel mapping
3097 	 * for it.
3098 	 */
3099 	err = gen_pool_add_virt(hcd->localmem_pool, (unsigned long)local_mem,
3100 				dma, size, dev_to_node(hcd->self.sysdev));
3101 	if (err < 0) {
3102 		dev_err(hcd->self.sysdev, "gen_pool_add_virt failed with %d\n",
3103 			err);
3104 		return err;
3105 	}
3106 
3107 	return 0;
3108 }
3109 EXPORT_SYMBOL_GPL(usb_hcd_setup_local_mem);
3110 
3111 /*-------------------------------------------------------------------------*/
3112 
3113 #if IS_ENABLED(CONFIG_USB_MON)
3114 
3115 const struct usb_mon_operations *mon_ops;
3116 
3117 /*
3118  * The registration is unlocked.
3119  * We do it this way because we do not want to lock in hot paths.
3120  *
3121  * Notice that the code is minimally error-proof. Because usbmon needs
3122  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
3123  */
3124 
3125 int usb_mon_register(const struct usb_mon_operations *ops)
3126 {
3127 
3128 	if (mon_ops)
3129 		return -EBUSY;
3130 
3131 	mon_ops = ops;
3132 	mb();
3133 	return 0;
3134 }
3135 EXPORT_SYMBOL_GPL (usb_mon_register);
3136 
3137 void usb_mon_deregister (void)
3138 {
3139 
3140 	if (mon_ops == NULL) {
3141 		printk(KERN_ERR "USB: monitor was not registered\n");
3142 		return;
3143 	}
3144 	mon_ops = NULL;
3145 	mb();
3146 }
3147 EXPORT_SYMBOL_GPL (usb_mon_deregister);
3148 
3149 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
3150