xref: /openbmc/linux/drivers/usb/core/hcd.c (revision 6562c9ac)
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  * or have restrictions on addressable DRAM.
1256  * The usb core itself is however optimized for host controllers that can dma
1257  * using regular system memory - like pci devices doing bus mastering.
1258  *
1259  * To support host controllers with limited dma capabilities we provide dma
1260  * bounce buffers. This feature can be enabled by initializing
1261  * hcd->localmem_pool using usb_hcd_setup_local_mem().
1262  *
1263  * The initialized hcd->localmem_pool then tells the usb code to allocate all
1264  * data for dma using the genalloc API.
1265  *
1266  * So, to summarize...
1267  *
1268  * - We need "local" memory, canonical example being
1269  *   a small SRAM on a discrete controller being the
1270  *   only memory that the controller can read ...
1271  *   (a) "normal" kernel memory is no good, and
1272  *   (b) there's not enough to share
1273  *
1274  * - So we use that, even though the primary requirement
1275  *   is that the memory be "local" (hence addressable
1276  *   by that device), not "coherent".
1277  *
1278  */
1279 
1280 static int hcd_alloc_coherent(struct usb_bus *bus,
1281 			      gfp_t mem_flags, dma_addr_t *dma_handle,
1282 			      void **vaddr_handle, size_t size,
1283 			      enum dma_data_direction dir)
1284 {
1285 	unsigned char *vaddr;
1286 
1287 	if (*vaddr_handle == NULL) {
1288 		WARN_ON_ONCE(1);
1289 		return -EFAULT;
1290 	}
1291 
1292 	vaddr = hcd_buffer_alloc(bus, size + sizeof(unsigned long),
1293 				 mem_flags, dma_handle);
1294 	if (!vaddr)
1295 		return -ENOMEM;
1296 
1297 	/*
1298 	 * Store the virtual address of the buffer at the end
1299 	 * of the allocated dma buffer. The size of the buffer
1300 	 * may be uneven so use unaligned functions instead
1301 	 * of just rounding up. It makes sense to optimize for
1302 	 * memory footprint over access speed since the amount
1303 	 * of memory available for dma may be limited.
1304 	 */
1305 	put_unaligned((unsigned long)*vaddr_handle,
1306 		      (unsigned long *)(vaddr + size));
1307 
1308 	if (dir == DMA_TO_DEVICE)
1309 		memcpy(vaddr, *vaddr_handle, size);
1310 
1311 	*vaddr_handle = vaddr;
1312 	return 0;
1313 }
1314 
1315 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1316 			      void **vaddr_handle, size_t size,
1317 			      enum dma_data_direction dir)
1318 {
1319 	unsigned char *vaddr = *vaddr_handle;
1320 
1321 	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1322 
1323 	if (dir == DMA_FROM_DEVICE)
1324 		memcpy(vaddr, *vaddr_handle, size);
1325 
1326 	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1327 
1328 	*vaddr_handle = vaddr;
1329 	*dma_handle = 0;
1330 }
1331 
1332 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1333 {
1334 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1335 	    (urb->transfer_flags & URB_SETUP_MAP_SINGLE))
1336 		dma_unmap_single(hcd->self.sysdev,
1337 				urb->setup_dma,
1338 				sizeof(struct usb_ctrlrequest),
1339 				DMA_TO_DEVICE);
1340 	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1341 		hcd_free_coherent(urb->dev->bus,
1342 				&urb->setup_dma,
1343 				(void **) &urb->setup_packet,
1344 				sizeof(struct usb_ctrlrequest),
1345 				DMA_TO_DEVICE);
1346 
1347 	/* Make it safe to call this routine more than once */
1348 	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1349 }
1350 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1351 
1352 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1353 {
1354 	if (hcd->driver->unmap_urb_for_dma)
1355 		hcd->driver->unmap_urb_for_dma(hcd, urb);
1356 	else
1357 		usb_hcd_unmap_urb_for_dma(hcd, urb);
1358 }
1359 
1360 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1361 {
1362 	enum dma_data_direction dir;
1363 
1364 	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1365 
1366 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1367 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1368 	    (urb->transfer_flags & URB_DMA_MAP_SG))
1369 		dma_unmap_sg(hcd->self.sysdev,
1370 				urb->sg,
1371 				urb->num_sgs,
1372 				dir);
1373 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1374 		 (urb->transfer_flags & URB_DMA_MAP_PAGE))
1375 		dma_unmap_page(hcd->self.sysdev,
1376 				urb->transfer_dma,
1377 				urb->transfer_buffer_length,
1378 				dir);
1379 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1380 		 (urb->transfer_flags & URB_DMA_MAP_SINGLE))
1381 		dma_unmap_single(hcd->self.sysdev,
1382 				urb->transfer_dma,
1383 				urb->transfer_buffer_length,
1384 				dir);
1385 	else if (urb->transfer_flags & URB_MAP_LOCAL)
1386 		hcd_free_coherent(urb->dev->bus,
1387 				&urb->transfer_dma,
1388 				&urb->transfer_buffer,
1389 				urb->transfer_buffer_length,
1390 				dir);
1391 
1392 	/* Make it safe to call this routine more than once */
1393 	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1394 			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1395 }
1396 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1397 
1398 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1399 			   gfp_t mem_flags)
1400 {
1401 	if (hcd->driver->map_urb_for_dma)
1402 		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1403 	else
1404 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1405 }
1406 
1407 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1408 			    gfp_t mem_flags)
1409 {
1410 	enum dma_data_direction dir;
1411 	int ret = 0;
1412 
1413 	/* Map the URB's buffers for DMA access.
1414 	 * Lower level HCD code should use *_dma exclusively,
1415 	 * unless it uses pio or talks to another transport,
1416 	 * or uses the provided scatter gather list for bulk.
1417 	 */
1418 
1419 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1420 		if (hcd->self.uses_pio_for_control)
1421 			return ret;
1422 		if (hcd->localmem_pool) {
1423 			ret = hcd_alloc_coherent(
1424 					urb->dev->bus, mem_flags,
1425 					&urb->setup_dma,
1426 					(void **)&urb->setup_packet,
1427 					sizeof(struct usb_ctrlrequest),
1428 					DMA_TO_DEVICE);
1429 			if (ret)
1430 				return ret;
1431 			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1432 		} else if (hcd_uses_dma(hcd)) {
1433 			if (object_is_on_stack(urb->setup_packet)) {
1434 				WARN_ONCE(1, "setup packet is on stack\n");
1435 				return -EAGAIN;
1436 			}
1437 
1438 			urb->setup_dma = dma_map_single(
1439 					hcd->self.sysdev,
1440 					urb->setup_packet,
1441 					sizeof(struct usb_ctrlrequest),
1442 					DMA_TO_DEVICE);
1443 			if (dma_mapping_error(hcd->self.sysdev,
1444 						urb->setup_dma))
1445 				return -EAGAIN;
1446 			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1447 		}
1448 	}
1449 
1450 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1451 	if (urb->transfer_buffer_length != 0
1452 	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1453 		if (hcd->localmem_pool) {
1454 			ret = hcd_alloc_coherent(
1455 					urb->dev->bus, mem_flags,
1456 					&urb->transfer_dma,
1457 					&urb->transfer_buffer,
1458 					urb->transfer_buffer_length,
1459 					dir);
1460 			if (ret == 0)
1461 				urb->transfer_flags |= URB_MAP_LOCAL;
1462 		} else if (hcd_uses_dma(hcd)) {
1463 			if (urb->num_sgs) {
1464 				int n;
1465 
1466 				/* We don't support sg for isoc transfers ! */
1467 				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1468 					WARN_ON(1);
1469 					return -EINVAL;
1470 				}
1471 
1472 				n = dma_map_sg(
1473 						hcd->self.sysdev,
1474 						urb->sg,
1475 						urb->num_sgs,
1476 						dir);
1477 				if (n <= 0)
1478 					ret = -EAGAIN;
1479 				else
1480 					urb->transfer_flags |= URB_DMA_MAP_SG;
1481 				urb->num_mapped_sgs = n;
1482 				if (n != urb->num_sgs)
1483 					urb->transfer_flags |=
1484 							URB_DMA_SG_COMBINED;
1485 			} else if (urb->sg) {
1486 				struct scatterlist *sg = urb->sg;
1487 				urb->transfer_dma = dma_map_page(
1488 						hcd->self.sysdev,
1489 						sg_page(sg),
1490 						sg->offset,
1491 						urb->transfer_buffer_length,
1492 						dir);
1493 				if (dma_mapping_error(hcd->self.sysdev,
1494 						urb->transfer_dma))
1495 					ret = -EAGAIN;
1496 				else
1497 					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1498 			} else if (object_is_on_stack(urb->transfer_buffer)) {
1499 				WARN_ONCE(1, "transfer buffer is on stack\n");
1500 				ret = -EAGAIN;
1501 			} else {
1502 				urb->transfer_dma = dma_map_single(
1503 						hcd->self.sysdev,
1504 						urb->transfer_buffer,
1505 						urb->transfer_buffer_length,
1506 						dir);
1507 				if (dma_mapping_error(hcd->self.sysdev,
1508 						urb->transfer_dma))
1509 					ret = -EAGAIN;
1510 				else
1511 					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1512 			}
1513 		}
1514 		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1515 				URB_SETUP_MAP_LOCAL)))
1516 			usb_hcd_unmap_urb_for_dma(hcd, urb);
1517 	}
1518 	return ret;
1519 }
1520 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1521 
1522 /*-------------------------------------------------------------------------*/
1523 
1524 /* may be called in any context with a valid urb->dev usecount
1525  * caller surrenders "ownership" of urb
1526  * expects usb_submit_urb() to have sanity checked and conditioned all
1527  * inputs in the urb
1528  */
1529 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1530 {
1531 	int			status;
1532 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1533 
1534 	/* increment urb's reference count as part of giving it to the HCD
1535 	 * (which will control it).  HCD guarantees that it either returns
1536 	 * an error or calls giveback(), but not both.
1537 	 */
1538 	usb_get_urb(urb);
1539 	atomic_inc(&urb->use_count);
1540 	atomic_inc(&urb->dev->urbnum);
1541 	usbmon_urb_submit(&hcd->self, urb);
1542 
1543 	/* NOTE requirements on root-hub callers (usbfs and the hub
1544 	 * driver, for now):  URBs' urb->transfer_buffer must be
1545 	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1546 	 * they could clobber root hub response data.  Also, control
1547 	 * URBs must be submitted in process context with interrupts
1548 	 * enabled.
1549 	 */
1550 
1551 	if (is_root_hub(urb->dev)) {
1552 		status = rh_urb_enqueue(hcd, urb);
1553 	} else {
1554 		status = map_urb_for_dma(hcd, urb, mem_flags);
1555 		if (likely(status == 0)) {
1556 			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1557 			if (unlikely(status))
1558 				unmap_urb_for_dma(hcd, urb);
1559 		}
1560 	}
1561 
1562 	if (unlikely(status)) {
1563 		usbmon_urb_submit_error(&hcd->self, urb, status);
1564 		urb->hcpriv = NULL;
1565 		INIT_LIST_HEAD(&urb->urb_list);
1566 		atomic_dec(&urb->use_count);
1567 		/*
1568 		 * Order the write of urb->use_count above before the read
1569 		 * of urb->reject below.  Pairs with the memory barriers in
1570 		 * usb_kill_urb() and usb_poison_urb().
1571 		 */
1572 		smp_mb__after_atomic();
1573 
1574 		atomic_dec(&urb->dev->urbnum);
1575 		if (atomic_read(&urb->reject))
1576 			wake_up(&usb_kill_urb_queue);
1577 		usb_put_urb(urb);
1578 	}
1579 	return status;
1580 }
1581 
1582 /*-------------------------------------------------------------------------*/
1583 
1584 /* this makes the hcd giveback() the urb more quickly, by kicking it
1585  * off hardware queues (which may take a while) and returning it as
1586  * soon as practical.  we've already set up the urb's return status,
1587  * but we can't know if the callback completed already.
1588  */
1589 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1590 {
1591 	int		value;
1592 
1593 	if (is_root_hub(urb->dev))
1594 		value = usb_rh_urb_dequeue(hcd, urb, status);
1595 	else {
1596 
1597 		/* The only reason an HCD might fail this call is if
1598 		 * it has not yet fully queued the urb to begin with.
1599 		 * Such failures should be harmless. */
1600 		value = hcd->driver->urb_dequeue(hcd, urb, status);
1601 	}
1602 	return value;
1603 }
1604 
1605 /*
1606  * called in any context
1607  *
1608  * caller guarantees urb won't be recycled till both unlink()
1609  * and the urb's completion function return
1610  */
1611 int usb_hcd_unlink_urb (struct urb *urb, int status)
1612 {
1613 	struct usb_hcd		*hcd;
1614 	struct usb_device	*udev = urb->dev;
1615 	int			retval = -EIDRM;
1616 	unsigned long		flags;
1617 
1618 	/* Prevent the device and bus from going away while
1619 	 * the unlink is carried out.  If they are already gone
1620 	 * then urb->use_count must be 0, since disconnected
1621 	 * devices can't have any active URBs.
1622 	 */
1623 	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1624 	if (atomic_read(&urb->use_count) > 0) {
1625 		retval = 0;
1626 		usb_get_dev(udev);
1627 	}
1628 	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1629 	if (retval == 0) {
1630 		hcd = bus_to_hcd(urb->dev->bus);
1631 		retval = unlink1(hcd, urb, status);
1632 		if (retval == 0)
1633 			retval = -EINPROGRESS;
1634 		else if (retval != -EIDRM && retval != -EBUSY)
1635 			dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n",
1636 					urb, retval);
1637 		usb_put_dev(udev);
1638 	}
1639 	return retval;
1640 }
1641 
1642 /*-------------------------------------------------------------------------*/
1643 
1644 static void __usb_hcd_giveback_urb(struct urb *urb)
1645 {
1646 	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1647 	struct usb_anchor *anchor = urb->anchor;
1648 	int status = urb->unlinked;
1649 
1650 	urb->hcpriv = NULL;
1651 	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1652 	    urb->actual_length < urb->transfer_buffer_length &&
1653 	    !status))
1654 		status = -EREMOTEIO;
1655 
1656 	unmap_urb_for_dma(hcd, urb);
1657 	usbmon_urb_complete(&hcd->self, urb, status);
1658 	usb_anchor_suspend_wakeups(anchor);
1659 	usb_unanchor_urb(urb);
1660 	if (likely(status == 0))
1661 		usb_led_activity(USB_LED_EVENT_HOST);
1662 
1663 	/* pass ownership to the completion handler */
1664 	urb->status = status;
1665 	/*
1666 	 * This function can be called in task context inside another remote
1667 	 * coverage collection section, but kcov doesn't support that kind of
1668 	 * recursion yet. Only collect coverage in softirq context for now.
1669 	 */
1670 	kcov_remote_start_usb_softirq((u64)urb->dev->bus->busnum);
1671 	urb->complete(urb);
1672 	kcov_remote_stop_softirq();
1673 
1674 	usb_anchor_resume_wakeups(anchor);
1675 	atomic_dec(&urb->use_count);
1676 	/*
1677 	 * Order the write of urb->use_count above before the read
1678 	 * of urb->reject below.  Pairs with the memory barriers in
1679 	 * usb_kill_urb() and usb_poison_urb().
1680 	 */
1681 	smp_mb__after_atomic();
1682 
1683 	if (unlikely(atomic_read(&urb->reject)))
1684 		wake_up(&usb_kill_urb_queue);
1685 	usb_put_urb(urb);
1686 }
1687 
1688 static void usb_giveback_urb_bh(struct tasklet_struct *t)
1689 {
1690 	struct giveback_urb_bh *bh = from_tasklet(bh, t, bh);
1691 	struct list_head local_list;
1692 
1693 	spin_lock_irq(&bh->lock);
1694 	bh->running = true;
1695 	list_replace_init(&bh->head, &local_list);
1696 	spin_unlock_irq(&bh->lock);
1697 
1698 	while (!list_empty(&local_list)) {
1699 		struct urb *urb;
1700 
1701 		urb = list_entry(local_list.next, struct urb, urb_list);
1702 		list_del_init(&urb->urb_list);
1703 		bh->completing_ep = urb->ep;
1704 		__usb_hcd_giveback_urb(urb);
1705 		bh->completing_ep = NULL;
1706 	}
1707 
1708 	/*
1709 	 * giveback new URBs next time to prevent this function
1710 	 * from not exiting for a long time.
1711 	 */
1712 	spin_lock_irq(&bh->lock);
1713 	if (!list_empty(&bh->head)) {
1714 		if (bh->high_prio)
1715 			tasklet_hi_schedule(&bh->bh);
1716 		else
1717 			tasklet_schedule(&bh->bh);
1718 	}
1719 	bh->running = false;
1720 	spin_unlock_irq(&bh->lock);
1721 }
1722 
1723 /**
1724  * usb_hcd_giveback_urb - return URB from HCD to device driver
1725  * @hcd: host controller returning the URB
1726  * @urb: urb being returned to the USB device driver.
1727  * @status: completion status code for the URB.
1728  *
1729  * Context: atomic. The completion callback is invoked in caller's context.
1730  * For HCDs with HCD_BH flag set, the completion callback is invoked in tasklet
1731  * context (except for URBs submitted to the root hub which always complete in
1732  * caller's context).
1733  *
1734  * This hands the URB from HCD to its USB device driver, using its
1735  * completion function.  The HCD has freed all per-urb resources
1736  * (and is done using urb->hcpriv).  It also released all HCD locks;
1737  * the device driver won't cause problems if it frees, modifies,
1738  * or resubmits this URB.
1739  *
1740  * If @urb was unlinked, the value of @status will be overridden by
1741  * @urb->unlinked.  Erroneous short transfers are detected in case
1742  * the HCD hasn't checked for them.
1743  */
1744 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1745 {
1746 	struct giveback_urb_bh *bh;
1747 	bool running;
1748 
1749 	/* pass status to tasklet via unlinked */
1750 	if (likely(!urb->unlinked))
1751 		urb->unlinked = status;
1752 
1753 	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1754 		__usb_hcd_giveback_urb(urb);
1755 		return;
1756 	}
1757 
1758 	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe))
1759 		bh = &hcd->high_prio_bh;
1760 	else
1761 		bh = &hcd->low_prio_bh;
1762 
1763 	spin_lock(&bh->lock);
1764 	list_add_tail(&urb->urb_list, &bh->head);
1765 	running = bh->running;
1766 	spin_unlock(&bh->lock);
1767 
1768 	if (running)
1769 		;
1770 	else if (bh->high_prio)
1771 		tasklet_hi_schedule(&bh->bh);
1772 	else
1773 		tasklet_schedule(&bh->bh);
1774 }
1775 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1776 
1777 /*-------------------------------------------------------------------------*/
1778 
1779 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1780  * queue to drain completely.  The caller must first insure that no more
1781  * URBs can be submitted for this endpoint.
1782  */
1783 void usb_hcd_flush_endpoint(struct usb_device *udev,
1784 		struct usb_host_endpoint *ep)
1785 {
1786 	struct usb_hcd		*hcd;
1787 	struct urb		*urb;
1788 
1789 	if (!ep)
1790 		return;
1791 	might_sleep();
1792 	hcd = bus_to_hcd(udev->bus);
1793 
1794 	/* No more submits can occur */
1795 	spin_lock_irq(&hcd_urb_list_lock);
1796 rescan:
1797 	list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) {
1798 		int	is_in;
1799 
1800 		if (urb->unlinked)
1801 			continue;
1802 		usb_get_urb (urb);
1803 		is_in = usb_urb_dir_in(urb);
1804 		spin_unlock(&hcd_urb_list_lock);
1805 
1806 		/* kick hcd */
1807 		unlink1(hcd, urb, -ESHUTDOWN);
1808 		dev_dbg (hcd->self.controller,
1809 			"shutdown urb %pK ep%d%s-%s\n",
1810 			urb, usb_endpoint_num(&ep->desc),
1811 			is_in ? "in" : "out",
1812 			usb_ep_type_string(usb_endpoint_type(&ep->desc)));
1813 		usb_put_urb (urb);
1814 
1815 		/* list contents may have changed */
1816 		spin_lock(&hcd_urb_list_lock);
1817 		goto rescan;
1818 	}
1819 	spin_unlock_irq(&hcd_urb_list_lock);
1820 
1821 	/* Wait until the endpoint queue is completely empty */
1822 	while (!list_empty (&ep->urb_list)) {
1823 		spin_lock_irq(&hcd_urb_list_lock);
1824 
1825 		/* The list may have changed while we acquired the spinlock */
1826 		urb = NULL;
1827 		if (!list_empty (&ep->urb_list)) {
1828 			urb = list_entry (ep->urb_list.prev, struct urb,
1829 					urb_list);
1830 			usb_get_urb (urb);
1831 		}
1832 		spin_unlock_irq(&hcd_urb_list_lock);
1833 
1834 		if (urb) {
1835 			usb_kill_urb (urb);
1836 			usb_put_urb (urb);
1837 		}
1838 	}
1839 }
1840 
1841 /**
1842  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1843  *				the bus bandwidth
1844  * @udev: target &usb_device
1845  * @new_config: new configuration to install
1846  * @cur_alt: the current alternate interface setting
1847  * @new_alt: alternate interface setting that is being installed
1848  *
1849  * To change configurations, pass in the new configuration in new_config,
1850  * and pass NULL for cur_alt and new_alt.
1851  *
1852  * To reset a device's configuration (put the device in the ADDRESSED state),
1853  * pass in NULL for new_config, cur_alt, and new_alt.
1854  *
1855  * To change alternate interface settings, pass in NULL for new_config,
1856  * pass in the current alternate interface setting in cur_alt,
1857  * and pass in the new alternate interface setting in new_alt.
1858  *
1859  * Return: An error if the requested bandwidth change exceeds the
1860  * bus bandwidth or host controller internal resources.
1861  */
1862 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1863 		struct usb_host_config *new_config,
1864 		struct usb_host_interface *cur_alt,
1865 		struct usb_host_interface *new_alt)
1866 {
1867 	int num_intfs, i, j;
1868 	struct usb_host_interface *alt = NULL;
1869 	int ret = 0;
1870 	struct usb_hcd *hcd;
1871 	struct usb_host_endpoint *ep;
1872 
1873 	hcd = bus_to_hcd(udev->bus);
1874 	if (!hcd->driver->check_bandwidth)
1875 		return 0;
1876 
1877 	/* Configuration is being removed - set configuration 0 */
1878 	if (!new_config && !cur_alt) {
1879 		for (i = 1; i < 16; ++i) {
1880 			ep = udev->ep_out[i];
1881 			if (ep)
1882 				hcd->driver->drop_endpoint(hcd, udev, ep);
1883 			ep = udev->ep_in[i];
1884 			if (ep)
1885 				hcd->driver->drop_endpoint(hcd, udev, ep);
1886 		}
1887 		hcd->driver->check_bandwidth(hcd, udev);
1888 		return 0;
1889 	}
1890 	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1891 	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1892 	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1893 	 * ok to exclude it.
1894 	 */
1895 	if (new_config) {
1896 		num_intfs = new_config->desc.bNumInterfaces;
1897 		/* Remove endpoints (except endpoint 0, which is always on the
1898 		 * schedule) from the old config from the schedule
1899 		 */
1900 		for (i = 1; i < 16; ++i) {
1901 			ep = udev->ep_out[i];
1902 			if (ep) {
1903 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1904 				if (ret < 0)
1905 					goto reset;
1906 			}
1907 			ep = udev->ep_in[i];
1908 			if (ep) {
1909 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1910 				if (ret < 0)
1911 					goto reset;
1912 			}
1913 		}
1914 		for (i = 0; i < num_intfs; ++i) {
1915 			struct usb_host_interface *first_alt;
1916 			int iface_num;
1917 
1918 			first_alt = &new_config->intf_cache[i]->altsetting[0];
1919 			iface_num = first_alt->desc.bInterfaceNumber;
1920 			/* Set up endpoints for alternate interface setting 0 */
1921 			alt = usb_find_alt_setting(new_config, iface_num, 0);
1922 			if (!alt)
1923 				/* No alt setting 0? Pick the first setting. */
1924 				alt = first_alt;
1925 
1926 			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1927 				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1928 				if (ret < 0)
1929 					goto reset;
1930 			}
1931 		}
1932 	}
1933 	if (cur_alt && new_alt) {
1934 		struct usb_interface *iface = usb_ifnum_to_if(udev,
1935 				cur_alt->desc.bInterfaceNumber);
1936 
1937 		if (!iface)
1938 			return -EINVAL;
1939 		if (iface->resetting_device) {
1940 			/*
1941 			 * The USB core just reset the device, so the xHCI host
1942 			 * and the device will think alt setting 0 is installed.
1943 			 * However, the USB core will pass in the alternate
1944 			 * setting installed before the reset as cur_alt.  Dig
1945 			 * out the alternate setting 0 structure, or the first
1946 			 * alternate setting if a broken device doesn't have alt
1947 			 * setting 0.
1948 			 */
1949 			cur_alt = usb_altnum_to_altsetting(iface, 0);
1950 			if (!cur_alt)
1951 				cur_alt = &iface->altsetting[0];
1952 		}
1953 
1954 		/* Drop all the endpoints in the current alt setting */
1955 		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
1956 			ret = hcd->driver->drop_endpoint(hcd, udev,
1957 					&cur_alt->endpoint[i]);
1958 			if (ret < 0)
1959 				goto reset;
1960 		}
1961 		/* Add all the endpoints in the new alt setting */
1962 		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
1963 			ret = hcd->driver->add_endpoint(hcd, udev,
1964 					&new_alt->endpoint[i]);
1965 			if (ret < 0)
1966 				goto reset;
1967 		}
1968 	}
1969 	ret = hcd->driver->check_bandwidth(hcd, udev);
1970 reset:
1971 	if (ret < 0)
1972 		hcd->driver->reset_bandwidth(hcd, udev);
1973 	return ret;
1974 }
1975 
1976 /* Disables the endpoint: synchronizes with the hcd to make sure all
1977  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
1978  * have been called previously.  Use for set_configuration, set_interface,
1979  * driver removal, physical disconnect.
1980  *
1981  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
1982  * type, maxpacket size, toggle, halt status, and scheduling.
1983  */
1984 void usb_hcd_disable_endpoint(struct usb_device *udev,
1985 		struct usb_host_endpoint *ep)
1986 {
1987 	struct usb_hcd		*hcd;
1988 
1989 	might_sleep();
1990 	hcd = bus_to_hcd(udev->bus);
1991 	if (hcd->driver->endpoint_disable)
1992 		hcd->driver->endpoint_disable(hcd, ep);
1993 }
1994 
1995 /**
1996  * usb_hcd_reset_endpoint - reset host endpoint state
1997  * @udev: USB device.
1998  * @ep:   the endpoint to reset.
1999  *
2000  * Resets any host endpoint state such as the toggle bit, sequence
2001  * number and current window.
2002  */
2003 void usb_hcd_reset_endpoint(struct usb_device *udev,
2004 			    struct usb_host_endpoint *ep)
2005 {
2006 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2007 
2008 	if (hcd->driver->endpoint_reset)
2009 		hcd->driver->endpoint_reset(hcd, ep);
2010 	else {
2011 		int epnum = usb_endpoint_num(&ep->desc);
2012 		int is_out = usb_endpoint_dir_out(&ep->desc);
2013 		int is_control = usb_endpoint_xfer_control(&ep->desc);
2014 
2015 		usb_settoggle(udev, epnum, is_out, 0);
2016 		if (is_control)
2017 			usb_settoggle(udev, epnum, !is_out, 0);
2018 	}
2019 }
2020 
2021 /**
2022  * usb_alloc_streams - allocate bulk endpoint stream IDs.
2023  * @interface:		alternate setting that includes all endpoints.
2024  * @eps:		array of endpoints that need streams.
2025  * @num_eps:		number of endpoints in the array.
2026  * @num_streams:	number of streams to allocate.
2027  * @mem_flags:		flags hcd should use to allocate memory.
2028  *
2029  * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
2030  * Drivers may queue multiple transfers to different stream IDs, which may
2031  * complete in a different order than they were queued.
2032  *
2033  * Return: On success, the number of allocated streams. On failure, a negative
2034  * error code.
2035  */
2036 int usb_alloc_streams(struct usb_interface *interface,
2037 		struct usb_host_endpoint **eps, unsigned int num_eps,
2038 		unsigned int num_streams, gfp_t mem_flags)
2039 {
2040 	struct usb_hcd *hcd;
2041 	struct usb_device *dev;
2042 	int i, ret;
2043 
2044 	dev = interface_to_usbdev(interface);
2045 	hcd = bus_to_hcd(dev->bus);
2046 	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2047 		return -EINVAL;
2048 	if (dev->speed < USB_SPEED_SUPER)
2049 		return -EINVAL;
2050 	if (dev->state < USB_STATE_CONFIGURED)
2051 		return -ENODEV;
2052 
2053 	for (i = 0; i < num_eps; i++) {
2054 		/* Streams only apply to bulk endpoints. */
2055 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2056 			return -EINVAL;
2057 		/* Re-alloc is not allowed */
2058 		if (eps[i]->streams)
2059 			return -EINVAL;
2060 	}
2061 
2062 	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2063 			num_streams, mem_flags);
2064 	if (ret < 0)
2065 		return ret;
2066 
2067 	for (i = 0; i < num_eps; i++)
2068 		eps[i]->streams = ret;
2069 
2070 	return ret;
2071 }
2072 EXPORT_SYMBOL_GPL(usb_alloc_streams);
2073 
2074 /**
2075  * usb_free_streams - free bulk endpoint stream IDs.
2076  * @interface:	alternate setting that includes all endpoints.
2077  * @eps:	array of endpoints to remove streams from.
2078  * @num_eps:	number of endpoints in the array.
2079  * @mem_flags:	flags hcd should use to allocate memory.
2080  *
2081  * Reverts a group of bulk endpoints back to not using stream IDs.
2082  * Can fail if we are given bad arguments, or HCD is broken.
2083  *
2084  * Return: 0 on success. On failure, a negative error code.
2085  */
2086 int usb_free_streams(struct usb_interface *interface,
2087 		struct usb_host_endpoint **eps, unsigned int num_eps,
2088 		gfp_t mem_flags)
2089 {
2090 	struct usb_hcd *hcd;
2091 	struct usb_device *dev;
2092 	int i, ret;
2093 
2094 	dev = interface_to_usbdev(interface);
2095 	hcd = bus_to_hcd(dev->bus);
2096 	if (dev->speed < USB_SPEED_SUPER)
2097 		return -EINVAL;
2098 
2099 	/* Double-free is not allowed */
2100 	for (i = 0; i < num_eps; i++)
2101 		if (!eps[i] || !eps[i]->streams)
2102 			return -EINVAL;
2103 
2104 	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2105 	if (ret < 0)
2106 		return ret;
2107 
2108 	for (i = 0; i < num_eps; i++)
2109 		eps[i]->streams = 0;
2110 
2111 	return ret;
2112 }
2113 EXPORT_SYMBOL_GPL(usb_free_streams);
2114 
2115 /* Protect against drivers that try to unlink URBs after the device
2116  * is gone, by waiting until all unlinks for @udev are finished.
2117  * Since we don't currently track URBs by device, simply wait until
2118  * nothing is running in the locked region of usb_hcd_unlink_urb().
2119  */
2120 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2121 {
2122 	spin_lock_irq(&hcd_urb_unlink_lock);
2123 	spin_unlock_irq(&hcd_urb_unlink_lock);
2124 }
2125 
2126 /*-------------------------------------------------------------------------*/
2127 
2128 /* called in any context */
2129 int usb_hcd_get_frame_number (struct usb_device *udev)
2130 {
2131 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
2132 
2133 	if (!HCD_RH_RUNNING(hcd))
2134 		return -ESHUTDOWN;
2135 	return hcd->driver->get_frame_number (hcd);
2136 }
2137 
2138 /*-------------------------------------------------------------------------*/
2139 #ifdef CONFIG_USB_HCD_TEST_MODE
2140 
2141 static void usb_ehset_completion(struct urb *urb)
2142 {
2143 	struct completion  *done = urb->context;
2144 
2145 	complete(done);
2146 }
2147 /*
2148  * Allocate and initialize a control URB. This request will be used by the
2149  * EHSET SINGLE_STEP_SET_FEATURE test in which the DATA and STATUS stages
2150  * of the GetDescriptor request are sent 15 seconds after the SETUP stage.
2151  * Return NULL if failed.
2152  */
2153 static struct urb *request_single_step_set_feature_urb(
2154 	struct usb_device	*udev,
2155 	void			*dr,
2156 	void			*buf,
2157 	struct completion	*done)
2158 {
2159 	struct urb *urb;
2160 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2161 	struct usb_host_endpoint *ep;
2162 
2163 	urb = usb_alloc_urb(0, GFP_KERNEL);
2164 	if (!urb)
2165 		return NULL;
2166 
2167 	urb->pipe = usb_rcvctrlpipe(udev, 0);
2168 	ep = (usb_pipein(urb->pipe) ? udev->ep_in : udev->ep_out)
2169 				[usb_pipeendpoint(urb->pipe)];
2170 	if (!ep) {
2171 		usb_free_urb(urb);
2172 		return NULL;
2173 	}
2174 
2175 	urb->ep = ep;
2176 	urb->dev = udev;
2177 	urb->setup_packet = (void *)dr;
2178 	urb->transfer_buffer = buf;
2179 	urb->transfer_buffer_length = USB_DT_DEVICE_SIZE;
2180 	urb->complete = usb_ehset_completion;
2181 	urb->status = -EINPROGRESS;
2182 	urb->actual_length = 0;
2183 	urb->transfer_flags = URB_DIR_IN;
2184 	usb_get_urb(urb);
2185 	atomic_inc(&urb->use_count);
2186 	atomic_inc(&urb->dev->urbnum);
2187 	if (map_urb_for_dma(hcd, urb, GFP_KERNEL)) {
2188 		usb_put_urb(urb);
2189 		usb_free_urb(urb);
2190 		return NULL;
2191 	}
2192 
2193 	urb->context = done;
2194 	return urb;
2195 }
2196 
2197 int ehset_single_step_set_feature(struct usb_hcd *hcd, int port)
2198 {
2199 	int retval = -ENOMEM;
2200 	struct usb_ctrlrequest *dr;
2201 	struct urb *urb;
2202 	struct usb_device *udev;
2203 	struct usb_device_descriptor *buf;
2204 	DECLARE_COMPLETION_ONSTACK(done);
2205 
2206 	/* Obtain udev of the rhub's child port */
2207 	udev = usb_hub_find_child(hcd->self.root_hub, port);
2208 	if (!udev) {
2209 		dev_err(hcd->self.controller, "No device attached to the RootHub\n");
2210 		return -ENODEV;
2211 	}
2212 	buf = kmalloc(USB_DT_DEVICE_SIZE, GFP_KERNEL);
2213 	if (!buf)
2214 		return -ENOMEM;
2215 
2216 	dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
2217 	if (!dr) {
2218 		kfree(buf);
2219 		return -ENOMEM;
2220 	}
2221 
2222 	/* Fill Setup packet for GetDescriptor */
2223 	dr->bRequestType = USB_DIR_IN;
2224 	dr->bRequest = USB_REQ_GET_DESCRIPTOR;
2225 	dr->wValue = cpu_to_le16(USB_DT_DEVICE << 8);
2226 	dr->wIndex = 0;
2227 	dr->wLength = cpu_to_le16(USB_DT_DEVICE_SIZE);
2228 	urb = request_single_step_set_feature_urb(udev, dr, buf, &done);
2229 	if (!urb)
2230 		goto cleanup;
2231 
2232 	/* Submit just the SETUP stage */
2233 	retval = hcd->driver->submit_single_step_set_feature(hcd, urb, 1);
2234 	if (retval)
2235 		goto out1;
2236 	if (!wait_for_completion_timeout(&done, msecs_to_jiffies(2000))) {
2237 		usb_kill_urb(urb);
2238 		retval = -ETIMEDOUT;
2239 		dev_err(hcd->self.controller,
2240 			"%s SETUP stage timed out on ep0\n", __func__);
2241 		goto out1;
2242 	}
2243 	msleep(15 * 1000);
2244 
2245 	/* Complete remaining DATA and STATUS stages using the same URB */
2246 	urb->status = -EINPROGRESS;
2247 	usb_get_urb(urb);
2248 	atomic_inc(&urb->use_count);
2249 	atomic_inc(&urb->dev->urbnum);
2250 	retval = hcd->driver->submit_single_step_set_feature(hcd, urb, 0);
2251 	if (!retval && !wait_for_completion_timeout(&done,
2252 						msecs_to_jiffies(2000))) {
2253 		usb_kill_urb(urb);
2254 		retval = -ETIMEDOUT;
2255 		dev_err(hcd->self.controller,
2256 			"%s IN stage timed out on ep0\n", __func__);
2257 	}
2258 out1:
2259 	usb_free_urb(urb);
2260 cleanup:
2261 	kfree(dr);
2262 	kfree(buf);
2263 	return retval;
2264 }
2265 EXPORT_SYMBOL_GPL(ehset_single_step_set_feature);
2266 #endif /* CONFIG_USB_HCD_TEST_MODE */
2267 
2268 /*-------------------------------------------------------------------------*/
2269 
2270 #ifdef	CONFIG_PM
2271 
2272 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2273 {
2274 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2275 	int		status;
2276 	int		old_state = hcd->state;
2277 
2278 	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2279 			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2280 			rhdev->do_remote_wakeup);
2281 	if (HCD_DEAD(hcd)) {
2282 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2283 		return 0;
2284 	}
2285 
2286 	if (!hcd->driver->bus_suspend) {
2287 		status = -ENOENT;
2288 	} else {
2289 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2290 		hcd->state = HC_STATE_QUIESCING;
2291 		status = hcd->driver->bus_suspend(hcd);
2292 	}
2293 	if (status == 0) {
2294 		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2295 		hcd->state = HC_STATE_SUSPENDED;
2296 
2297 		if (!PMSG_IS_AUTO(msg))
2298 			usb_phy_roothub_suspend(hcd->self.sysdev,
2299 						hcd->phy_roothub);
2300 
2301 		/* Did we race with a root-hub wakeup event? */
2302 		if (rhdev->do_remote_wakeup) {
2303 			char	buffer[6];
2304 
2305 			status = hcd->driver->hub_status_data(hcd, buffer);
2306 			if (status != 0) {
2307 				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2308 				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2309 				status = -EBUSY;
2310 			}
2311 		}
2312 	} else {
2313 		spin_lock_irq(&hcd_root_hub_lock);
2314 		if (!HCD_DEAD(hcd)) {
2315 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2316 			hcd->state = old_state;
2317 		}
2318 		spin_unlock_irq(&hcd_root_hub_lock);
2319 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2320 				"suspend", status);
2321 	}
2322 	return status;
2323 }
2324 
2325 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2326 {
2327 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2328 	int		status;
2329 	int		old_state = hcd->state;
2330 
2331 	dev_dbg(&rhdev->dev, "usb %sresume\n",
2332 			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2333 	if (HCD_DEAD(hcd)) {
2334 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2335 		return 0;
2336 	}
2337 
2338 	if (!PMSG_IS_AUTO(msg)) {
2339 		status = usb_phy_roothub_resume(hcd->self.sysdev,
2340 						hcd->phy_roothub);
2341 		if (status)
2342 			return status;
2343 	}
2344 
2345 	if (!hcd->driver->bus_resume)
2346 		return -ENOENT;
2347 	if (HCD_RH_RUNNING(hcd))
2348 		return 0;
2349 
2350 	hcd->state = HC_STATE_RESUMING;
2351 	status = hcd->driver->bus_resume(hcd);
2352 	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2353 	if (status == 0)
2354 		status = usb_phy_roothub_calibrate(hcd->phy_roothub);
2355 
2356 	if (status == 0) {
2357 		struct usb_device *udev;
2358 		int port1;
2359 
2360 		spin_lock_irq(&hcd_root_hub_lock);
2361 		if (!HCD_DEAD(hcd)) {
2362 			usb_set_device_state(rhdev, rhdev->actconfig
2363 					? USB_STATE_CONFIGURED
2364 					: USB_STATE_ADDRESS);
2365 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2366 			hcd->state = HC_STATE_RUNNING;
2367 		}
2368 		spin_unlock_irq(&hcd_root_hub_lock);
2369 
2370 		/*
2371 		 * Check whether any of the enabled ports on the root hub are
2372 		 * unsuspended.  If they are then a TRSMRCY delay is needed
2373 		 * (this is what the USB-2 spec calls a "global resume").
2374 		 * Otherwise we can skip the delay.
2375 		 */
2376 		usb_hub_for_each_child(rhdev, port1, udev) {
2377 			if (udev->state != USB_STATE_NOTATTACHED &&
2378 					!udev->port_is_suspended) {
2379 				usleep_range(10000, 11000);	/* TRSMRCY */
2380 				break;
2381 			}
2382 		}
2383 	} else {
2384 		hcd->state = old_state;
2385 		usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub);
2386 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2387 				"resume", status);
2388 		if (status != -ESHUTDOWN)
2389 			usb_hc_died(hcd);
2390 	}
2391 	return status;
2392 }
2393 
2394 /* Workqueue routine for root-hub remote wakeup */
2395 static void hcd_resume_work(struct work_struct *work)
2396 {
2397 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2398 	struct usb_device *udev = hcd->self.root_hub;
2399 
2400 	usb_remote_wakeup(udev);
2401 }
2402 
2403 /**
2404  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2405  * @hcd: host controller for this root hub
2406  *
2407  * The USB host controller calls this function when its root hub is
2408  * suspended (with the remote wakeup feature enabled) and a remote
2409  * wakeup request is received.  The routine submits a workqueue request
2410  * to resume the root hub (that is, manage its downstream ports again).
2411  */
2412 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2413 {
2414 	unsigned long flags;
2415 
2416 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2417 	if (hcd->rh_registered) {
2418 		pm_wakeup_event(&hcd->self.root_hub->dev, 0);
2419 		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2420 		queue_work(pm_wq, &hcd->wakeup_work);
2421 	}
2422 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2423 }
2424 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2425 
2426 #endif	/* CONFIG_PM */
2427 
2428 /*-------------------------------------------------------------------------*/
2429 
2430 #ifdef	CONFIG_USB_OTG
2431 
2432 /**
2433  * usb_bus_start_enum - start immediate enumeration (for OTG)
2434  * @bus: the bus (must use hcd framework)
2435  * @port_num: 1-based number of port; usually bus->otg_port
2436  * Context: atomic
2437  *
2438  * Starts enumeration, with an immediate reset followed later by
2439  * hub_wq identifying and possibly configuring the device.
2440  * This is needed by OTG controller drivers, where it helps meet
2441  * HNP protocol timing requirements for starting a port reset.
2442  *
2443  * Return: 0 if successful.
2444  */
2445 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2446 {
2447 	struct usb_hcd		*hcd;
2448 	int			status = -EOPNOTSUPP;
2449 
2450 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2451 	 * boards with root hubs hooked up to internal devices (instead of
2452 	 * just the OTG port) may need more attention to resetting...
2453 	 */
2454 	hcd = bus_to_hcd(bus);
2455 	if (port_num && hcd->driver->start_port_reset)
2456 		status = hcd->driver->start_port_reset(hcd, port_num);
2457 
2458 	/* allocate hub_wq shortly after (first) root port reset finishes;
2459 	 * it may issue others, until at least 50 msecs have passed.
2460 	 */
2461 	if (status == 0)
2462 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2463 	return status;
2464 }
2465 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2466 
2467 #endif
2468 
2469 /*-------------------------------------------------------------------------*/
2470 
2471 /**
2472  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2473  * @irq: the IRQ being raised
2474  * @__hcd: pointer to the HCD whose IRQ is being signaled
2475  *
2476  * If the controller isn't HALTed, calls the driver's irq handler.
2477  * Checks whether the controller is now dead.
2478  *
2479  * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2480  */
2481 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2482 {
2483 	struct usb_hcd		*hcd = __hcd;
2484 	irqreturn_t		rc;
2485 
2486 	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2487 		rc = IRQ_NONE;
2488 	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2489 		rc = IRQ_NONE;
2490 	else
2491 		rc = IRQ_HANDLED;
2492 
2493 	return rc;
2494 }
2495 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2496 
2497 /*-------------------------------------------------------------------------*/
2498 
2499 /* Workqueue routine for when the root-hub has died. */
2500 static void hcd_died_work(struct work_struct *work)
2501 {
2502 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, died_work);
2503 	static char *env[] = {
2504 		"ERROR=DEAD",
2505 		NULL
2506 	};
2507 
2508 	/* Notify user space that the host controller has died */
2509 	kobject_uevent_env(&hcd->self.root_hub->dev.kobj, KOBJ_OFFLINE, env);
2510 }
2511 
2512 /**
2513  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2514  * @hcd: pointer to the HCD representing the controller
2515  *
2516  * This is called by bus glue to report a USB host controller that died
2517  * while operations may still have been pending.  It's called automatically
2518  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2519  *
2520  * Only call this function with the primary HCD.
2521  */
2522 void usb_hc_died (struct usb_hcd *hcd)
2523 {
2524 	unsigned long flags;
2525 
2526 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2527 
2528 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2529 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2530 	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2531 	if (hcd->rh_registered) {
2532 		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2533 
2534 		/* make hub_wq clean up old urbs and devices */
2535 		usb_set_device_state (hcd->self.root_hub,
2536 				USB_STATE_NOTATTACHED);
2537 		usb_kick_hub_wq(hcd->self.root_hub);
2538 	}
2539 	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2540 		hcd = hcd->shared_hcd;
2541 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2542 		set_bit(HCD_FLAG_DEAD, &hcd->flags);
2543 		if (hcd->rh_registered) {
2544 			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2545 
2546 			/* make hub_wq clean up old urbs and devices */
2547 			usb_set_device_state(hcd->self.root_hub,
2548 					USB_STATE_NOTATTACHED);
2549 			usb_kick_hub_wq(hcd->self.root_hub);
2550 		}
2551 	}
2552 
2553 	/* Handle the case where this function gets called with a shared HCD */
2554 	if (usb_hcd_is_primary_hcd(hcd))
2555 		schedule_work(&hcd->died_work);
2556 	else
2557 		schedule_work(&hcd->primary_hcd->died_work);
2558 
2559 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2560 	/* Make sure that the other roothub is also deallocated. */
2561 }
2562 EXPORT_SYMBOL_GPL (usb_hc_died);
2563 
2564 /*-------------------------------------------------------------------------*/
2565 
2566 static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2567 {
2568 
2569 	spin_lock_init(&bh->lock);
2570 	INIT_LIST_HEAD(&bh->head);
2571 	tasklet_setup(&bh->bh, usb_giveback_urb_bh);
2572 }
2573 
2574 struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
2575 		struct device *sysdev, struct device *dev, const char *bus_name,
2576 		struct usb_hcd *primary_hcd)
2577 {
2578 	struct usb_hcd *hcd;
2579 
2580 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2581 	if (!hcd)
2582 		return NULL;
2583 	if (primary_hcd == NULL) {
2584 		hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex),
2585 				GFP_KERNEL);
2586 		if (!hcd->address0_mutex) {
2587 			kfree(hcd);
2588 			dev_dbg(dev, "hcd address0 mutex alloc failed\n");
2589 			return NULL;
2590 		}
2591 		mutex_init(hcd->address0_mutex);
2592 		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2593 				GFP_KERNEL);
2594 		if (!hcd->bandwidth_mutex) {
2595 			kfree(hcd->address0_mutex);
2596 			kfree(hcd);
2597 			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2598 			return NULL;
2599 		}
2600 		mutex_init(hcd->bandwidth_mutex);
2601 		dev_set_drvdata(dev, hcd);
2602 	} else {
2603 		mutex_lock(&usb_port_peer_mutex);
2604 		hcd->address0_mutex = primary_hcd->address0_mutex;
2605 		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2606 		hcd->primary_hcd = primary_hcd;
2607 		primary_hcd->primary_hcd = primary_hcd;
2608 		hcd->shared_hcd = primary_hcd;
2609 		primary_hcd->shared_hcd = hcd;
2610 		mutex_unlock(&usb_port_peer_mutex);
2611 	}
2612 
2613 	kref_init(&hcd->kref);
2614 
2615 	usb_bus_init(&hcd->self);
2616 	hcd->self.controller = dev;
2617 	hcd->self.sysdev = sysdev;
2618 	hcd->self.bus_name = bus_name;
2619 
2620 	timer_setup(&hcd->rh_timer, rh_timer_func, 0);
2621 #ifdef CONFIG_PM
2622 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2623 #endif
2624 
2625 	INIT_WORK(&hcd->died_work, hcd_died_work);
2626 
2627 	hcd->driver = driver;
2628 	hcd->speed = driver->flags & HCD_MASK;
2629 	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2630 			"USB Host Controller";
2631 	return hcd;
2632 }
2633 EXPORT_SYMBOL_GPL(__usb_create_hcd);
2634 
2635 /**
2636  * usb_create_shared_hcd - create and initialize an HCD structure
2637  * @driver: HC driver that will use this hcd
2638  * @dev: device for this HC, stored in hcd->self.controller
2639  * @bus_name: value to store in hcd->self.bus_name
2640  * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2641  *              PCI device.  Only allocate certain resources for the primary HCD
2642  *
2643  * Context: task context, might sleep.
2644  *
2645  * Allocate a struct usb_hcd, with extra space at the end for the
2646  * HC driver's private data.  Initialize the generic members of the
2647  * hcd structure.
2648  *
2649  * Return: On success, a pointer to the created and initialized HCD structure.
2650  * On failure (e.g. if memory is unavailable), %NULL.
2651  */
2652 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2653 		struct device *dev, const char *bus_name,
2654 		struct usb_hcd *primary_hcd)
2655 {
2656 	return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd);
2657 }
2658 EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2659 
2660 /**
2661  * usb_create_hcd - create and initialize an HCD structure
2662  * @driver: HC driver that will use this hcd
2663  * @dev: device for this HC, stored in hcd->self.controller
2664  * @bus_name: value to store in hcd->self.bus_name
2665  *
2666  * Context: task context, might sleep.
2667  *
2668  * Allocate a struct usb_hcd, with extra space at the end for the
2669  * HC driver's private data.  Initialize the generic members of the
2670  * hcd structure.
2671  *
2672  * Return: On success, a pointer to the created and initialized HCD
2673  * structure. On failure (e.g. if memory is unavailable), %NULL.
2674  */
2675 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2676 		struct device *dev, const char *bus_name)
2677 {
2678 	return __usb_create_hcd(driver, dev, dev, bus_name, NULL);
2679 }
2680 EXPORT_SYMBOL_GPL(usb_create_hcd);
2681 
2682 /*
2683  * Roothubs that share one PCI device must also share the bandwidth mutex.
2684  * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2685  * deallocated.
2686  *
2687  * Make sure to deallocate the bandwidth_mutex only when the last HCD is
2688  * freed.  When hcd_release() is called for either hcd in a peer set,
2689  * invalidate the peer's ->shared_hcd and ->primary_hcd pointers.
2690  */
2691 static void hcd_release(struct kref *kref)
2692 {
2693 	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2694 
2695 	mutex_lock(&usb_port_peer_mutex);
2696 	if (hcd->shared_hcd) {
2697 		struct usb_hcd *peer = hcd->shared_hcd;
2698 
2699 		peer->shared_hcd = NULL;
2700 		peer->primary_hcd = NULL;
2701 	} else {
2702 		kfree(hcd->address0_mutex);
2703 		kfree(hcd->bandwidth_mutex);
2704 	}
2705 	mutex_unlock(&usb_port_peer_mutex);
2706 	kfree(hcd);
2707 }
2708 
2709 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2710 {
2711 	if (hcd)
2712 		kref_get (&hcd->kref);
2713 	return hcd;
2714 }
2715 EXPORT_SYMBOL_GPL(usb_get_hcd);
2716 
2717 void usb_put_hcd (struct usb_hcd *hcd)
2718 {
2719 	if (hcd)
2720 		kref_put (&hcd->kref, hcd_release);
2721 }
2722 EXPORT_SYMBOL_GPL(usb_put_hcd);
2723 
2724 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2725 {
2726 	if (!hcd->primary_hcd)
2727 		return 1;
2728 	return hcd == hcd->primary_hcd;
2729 }
2730 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2731 
2732 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2733 {
2734 	if (!hcd->driver->find_raw_port_number)
2735 		return port1;
2736 
2737 	return hcd->driver->find_raw_port_number(hcd, port1);
2738 }
2739 
2740 static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2741 		unsigned int irqnum, unsigned long irqflags)
2742 {
2743 	int retval;
2744 
2745 	if (hcd->driver->irq) {
2746 
2747 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2748 				hcd->driver->description, hcd->self.busnum);
2749 		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2750 				hcd->irq_descr, hcd);
2751 		if (retval != 0) {
2752 			dev_err(hcd->self.controller,
2753 					"request interrupt %d failed\n",
2754 					irqnum);
2755 			return retval;
2756 		}
2757 		hcd->irq = irqnum;
2758 		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2759 				(hcd->driver->flags & HCD_MEMORY) ?
2760 					"io mem" : "io port",
2761 				(unsigned long long)hcd->rsrc_start);
2762 	} else {
2763 		hcd->irq = 0;
2764 		if (hcd->rsrc_start)
2765 			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2766 					(hcd->driver->flags & HCD_MEMORY) ?
2767 						"io mem" : "io port",
2768 					(unsigned long long)hcd->rsrc_start);
2769 	}
2770 	return 0;
2771 }
2772 
2773 /*
2774  * Before we free this root hub, flush in-flight peering attempts
2775  * and disable peer lookups
2776  */
2777 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2778 {
2779 	struct usb_device *rhdev;
2780 
2781 	mutex_lock(&usb_port_peer_mutex);
2782 	rhdev = hcd->self.root_hub;
2783 	hcd->self.root_hub = NULL;
2784 	mutex_unlock(&usb_port_peer_mutex);
2785 	usb_put_dev(rhdev);
2786 }
2787 
2788 /**
2789  * usb_stop_hcd - Halt the HCD
2790  * @hcd: the usb_hcd that has to be halted
2791  *
2792  * Stop the root-hub polling timer and invoke the HCD's ->stop callback.
2793  */
2794 static void usb_stop_hcd(struct usb_hcd *hcd)
2795 {
2796 	hcd->rh_pollable = 0;
2797 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2798 	del_timer_sync(&hcd->rh_timer);
2799 
2800 	hcd->driver->stop(hcd);
2801 	hcd->state = HC_STATE_HALT;
2802 
2803 	/* In case the HCD restarted the timer, stop it again. */
2804 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2805 	del_timer_sync(&hcd->rh_timer);
2806 }
2807 
2808 /**
2809  * usb_add_hcd - finish generic HCD structure initialization and register
2810  * @hcd: the usb_hcd structure to initialize
2811  * @irqnum: Interrupt line to allocate
2812  * @irqflags: Interrupt type flags
2813  *
2814  * Finish the remaining parts of generic HCD initialization: allocate the
2815  * buffers of consistent memory, register the bus, request the IRQ line,
2816  * and call the driver's reset() and start() routines.
2817  */
2818 int usb_add_hcd(struct usb_hcd *hcd,
2819 		unsigned int irqnum, unsigned long irqflags)
2820 {
2821 	int retval;
2822 	struct usb_device *rhdev;
2823 	struct usb_hcd *shared_hcd;
2824 
2825 	if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) {
2826 		hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev);
2827 		if (IS_ERR(hcd->phy_roothub))
2828 			return PTR_ERR(hcd->phy_roothub);
2829 
2830 		retval = usb_phy_roothub_init(hcd->phy_roothub);
2831 		if (retval)
2832 			return retval;
2833 
2834 		retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2835 						  PHY_MODE_USB_HOST_SS);
2836 		if (retval)
2837 			retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2838 							  PHY_MODE_USB_HOST);
2839 		if (retval)
2840 			goto err_usb_phy_roothub_power_on;
2841 
2842 		retval = usb_phy_roothub_power_on(hcd->phy_roothub);
2843 		if (retval)
2844 			goto err_usb_phy_roothub_power_on;
2845 	}
2846 
2847 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2848 
2849 	switch (authorized_default) {
2850 	case USB_AUTHORIZE_NONE:
2851 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_NONE;
2852 		break;
2853 
2854 	case USB_AUTHORIZE_ALL:
2855 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_ALL;
2856 		break;
2857 
2858 	case USB_AUTHORIZE_INTERNAL:
2859 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_INTERNAL;
2860 		break;
2861 
2862 	case USB_AUTHORIZE_WIRED:
2863 	default:
2864 		hcd->dev_policy = hcd->wireless ?
2865 			USB_DEVICE_AUTHORIZE_NONE : USB_DEVICE_AUTHORIZE_ALL;
2866 		break;
2867 	}
2868 
2869 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2870 
2871 	/* per default all interfaces are authorized */
2872 	set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
2873 
2874 	/* HC is in reset state, but accessible.  Now do the one-time init,
2875 	 * bottom up so that hcds can customize the root hubs before hub_wq
2876 	 * starts talking to them.  (Note, bus id is assigned early too.)
2877 	 */
2878 	retval = hcd_buffer_create(hcd);
2879 	if (retval != 0) {
2880 		dev_dbg(hcd->self.sysdev, "pool alloc failed\n");
2881 		goto err_create_buf;
2882 	}
2883 
2884 	retval = usb_register_bus(&hcd->self);
2885 	if (retval < 0)
2886 		goto err_register_bus;
2887 
2888 	rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2889 	if (rhdev == NULL) {
2890 		dev_err(hcd->self.sysdev, "unable to allocate root hub\n");
2891 		retval = -ENOMEM;
2892 		goto err_allocate_root_hub;
2893 	}
2894 	mutex_lock(&usb_port_peer_mutex);
2895 	hcd->self.root_hub = rhdev;
2896 	mutex_unlock(&usb_port_peer_mutex);
2897 
2898 	rhdev->rx_lanes = 1;
2899 	rhdev->tx_lanes = 1;
2900 	rhdev->ssp_rate = USB_SSP_GEN_UNKNOWN;
2901 
2902 	switch (hcd->speed) {
2903 	case HCD_USB11:
2904 		rhdev->speed = USB_SPEED_FULL;
2905 		break;
2906 	case HCD_USB2:
2907 		rhdev->speed = USB_SPEED_HIGH;
2908 		break;
2909 	case HCD_USB25:
2910 		rhdev->speed = USB_SPEED_WIRELESS;
2911 		break;
2912 	case HCD_USB3:
2913 		rhdev->speed = USB_SPEED_SUPER;
2914 		break;
2915 	case HCD_USB32:
2916 		rhdev->rx_lanes = 2;
2917 		rhdev->tx_lanes = 2;
2918 		rhdev->ssp_rate = USB_SSP_GEN_2x2;
2919 		rhdev->speed = USB_SPEED_SUPER_PLUS;
2920 		break;
2921 	case HCD_USB31:
2922 		rhdev->ssp_rate = USB_SSP_GEN_2x1;
2923 		rhdev->speed = USB_SPEED_SUPER_PLUS;
2924 		break;
2925 	default:
2926 		retval = -EINVAL;
2927 		goto err_set_rh_speed;
2928 	}
2929 
2930 	/* wakeup flag init defaults to "everything works" for root hubs,
2931 	 * but drivers can override it in reset() if needed, along with
2932 	 * recording the overall controller's system wakeup capability.
2933 	 */
2934 	device_set_wakeup_capable(&rhdev->dev, 1);
2935 
2936 	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2937 	 * registered.  But since the controller can die at any time,
2938 	 * let's initialize the flag before touching the hardware.
2939 	 */
2940 	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2941 
2942 	/* "reset" is misnamed; its role is now one-time init. the controller
2943 	 * should already have been reset (and boot firmware kicked off etc).
2944 	 */
2945 	if (hcd->driver->reset) {
2946 		retval = hcd->driver->reset(hcd);
2947 		if (retval < 0) {
2948 			dev_err(hcd->self.controller, "can't setup: %d\n",
2949 					retval);
2950 			goto err_hcd_driver_setup;
2951 		}
2952 	}
2953 	hcd->rh_pollable = 1;
2954 
2955 	retval = usb_phy_roothub_calibrate(hcd->phy_roothub);
2956 	if (retval)
2957 		goto err_hcd_driver_setup;
2958 
2959 	/* NOTE: root hub and controller capabilities may not be the same */
2960 	if (device_can_wakeup(hcd->self.controller)
2961 			&& device_can_wakeup(&hcd->self.root_hub->dev))
2962 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2963 
2964 	/* initialize tasklets */
2965 	init_giveback_urb_bh(&hcd->high_prio_bh);
2966 	hcd->high_prio_bh.high_prio = true;
2967 	init_giveback_urb_bh(&hcd->low_prio_bh);
2968 
2969 	/* enable irqs just before we start the controller,
2970 	 * if the BIOS provides legacy PCI irqs.
2971 	 */
2972 	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2973 		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2974 		if (retval)
2975 			goto err_request_irq;
2976 	}
2977 
2978 	hcd->state = HC_STATE_RUNNING;
2979 	retval = hcd->driver->start(hcd);
2980 	if (retval < 0) {
2981 		dev_err(hcd->self.controller, "startup error %d\n", retval);
2982 		goto err_hcd_driver_start;
2983 	}
2984 
2985 	/* starting here, usbcore will pay attention to the shared HCD roothub */
2986 	shared_hcd = hcd->shared_hcd;
2987 	if (!usb_hcd_is_primary_hcd(hcd) && shared_hcd && HCD_DEFER_RH_REGISTER(shared_hcd)) {
2988 		retval = register_root_hub(shared_hcd);
2989 		if (retval != 0)
2990 			goto err_register_root_hub;
2991 
2992 		if (shared_hcd->uses_new_polling && HCD_POLL_RH(shared_hcd))
2993 			usb_hcd_poll_rh_status(shared_hcd);
2994 	}
2995 
2996 	/* starting here, usbcore will pay attention to this root hub */
2997 	if (!HCD_DEFER_RH_REGISTER(hcd)) {
2998 		retval = register_root_hub(hcd);
2999 		if (retval != 0)
3000 			goto err_register_root_hub;
3001 
3002 		if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
3003 			usb_hcd_poll_rh_status(hcd);
3004 	}
3005 
3006 	return retval;
3007 
3008 err_register_root_hub:
3009 	usb_stop_hcd(hcd);
3010 err_hcd_driver_start:
3011 	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
3012 		free_irq(irqnum, hcd);
3013 err_request_irq:
3014 err_hcd_driver_setup:
3015 err_set_rh_speed:
3016 	usb_put_invalidate_rhdev(hcd);
3017 err_allocate_root_hub:
3018 	usb_deregister_bus(&hcd->self);
3019 err_register_bus:
3020 	hcd_buffer_destroy(hcd);
3021 err_create_buf:
3022 	usb_phy_roothub_power_off(hcd->phy_roothub);
3023 err_usb_phy_roothub_power_on:
3024 	usb_phy_roothub_exit(hcd->phy_roothub);
3025 
3026 	return retval;
3027 }
3028 EXPORT_SYMBOL_GPL(usb_add_hcd);
3029 
3030 /**
3031  * usb_remove_hcd - shutdown processing for generic HCDs
3032  * @hcd: the usb_hcd structure to remove
3033  *
3034  * Context: task context, might sleep.
3035  *
3036  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
3037  * invoking the HCD's stop() method.
3038  */
3039 void usb_remove_hcd(struct usb_hcd *hcd)
3040 {
3041 	struct usb_device *rhdev;
3042 	bool rh_registered;
3043 
3044 	if (!hcd) {
3045 		pr_debug("%s: hcd is NULL\n", __func__);
3046 		return;
3047 	}
3048 	rhdev = hcd->self.root_hub;
3049 
3050 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
3051 
3052 	usb_get_dev(rhdev);
3053 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
3054 	if (HC_IS_RUNNING (hcd->state))
3055 		hcd->state = HC_STATE_QUIESCING;
3056 
3057 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
3058 	spin_lock_irq (&hcd_root_hub_lock);
3059 	rh_registered = hcd->rh_registered;
3060 	hcd->rh_registered = 0;
3061 	spin_unlock_irq (&hcd_root_hub_lock);
3062 
3063 #ifdef CONFIG_PM
3064 	cancel_work_sync(&hcd->wakeup_work);
3065 #endif
3066 	cancel_work_sync(&hcd->died_work);
3067 
3068 	mutex_lock(&usb_bus_idr_lock);
3069 	if (rh_registered)
3070 		usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
3071 	mutex_unlock(&usb_bus_idr_lock);
3072 
3073 	/*
3074 	 * tasklet_kill() isn't needed here because:
3075 	 * - driver's disconnect() called from usb_disconnect() should
3076 	 *   make sure its URBs are completed during the disconnect()
3077 	 *   callback
3078 	 *
3079 	 * - it is too late to run complete() here since driver may have
3080 	 *   been removed already now
3081 	 */
3082 
3083 	/* Prevent any more root-hub status calls from the timer.
3084 	 * The HCD might still restart the timer (if a port status change
3085 	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
3086 	 * the hub_status_data() callback.
3087 	 */
3088 	usb_stop_hcd(hcd);
3089 
3090 	if (usb_hcd_is_primary_hcd(hcd)) {
3091 		if (hcd->irq > 0)
3092 			free_irq(hcd->irq, hcd);
3093 	}
3094 
3095 	usb_deregister_bus(&hcd->self);
3096 	hcd_buffer_destroy(hcd);
3097 
3098 	usb_phy_roothub_power_off(hcd->phy_roothub);
3099 	usb_phy_roothub_exit(hcd->phy_roothub);
3100 
3101 	usb_put_invalidate_rhdev(hcd);
3102 	hcd->flags = 0;
3103 }
3104 EXPORT_SYMBOL_GPL(usb_remove_hcd);
3105 
3106 void
3107 usb_hcd_platform_shutdown(struct platform_device *dev)
3108 {
3109 	struct usb_hcd *hcd = platform_get_drvdata(dev);
3110 
3111 	/* No need for pm_runtime_put(), we're shutting down */
3112 	pm_runtime_get_sync(&dev->dev);
3113 
3114 	if (hcd->driver->shutdown)
3115 		hcd->driver->shutdown(hcd);
3116 }
3117 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
3118 
3119 int usb_hcd_setup_local_mem(struct usb_hcd *hcd, phys_addr_t phys_addr,
3120 			    dma_addr_t dma, size_t size)
3121 {
3122 	int err;
3123 	void *local_mem;
3124 
3125 	hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, 4,
3126 						  dev_to_node(hcd->self.sysdev),
3127 						  dev_name(hcd->self.sysdev));
3128 	if (IS_ERR(hcd->localmem_pool))
3129 		return PTR_ERR(hcd->localmem_pool);
3130 
3131 	/*
3132 	 * if a physical SRAM address was passed, map it, otherwise
3133 	 * allocate system memory as a buffer.
3134 	 */
3135 	if (phys_addr)
3136 		local_mem = devm_memremap(hcd->self.sysdev, phys_addr,
3137 					  size, MEMREMAP_WC);
3138 	else
3139 		local_mem = dmam_alloc_attrs(hcd->self.sysdev, size, &dma,
3140 					     GFP_KERNEL,
3141 					     DMA_ATTR_WRITE_COMBINE);
3142 
3143 	if (IS_ERR(local_mem))
3144 		return PTR_ERR(local_mem);
3145 
3146 	/*
3147 	 * Here we pass a dma_addr_t but the arg type is a phys_addr_t.
3148 	 * It's not backed by system memory and thus there's no kernel mapping
3149 	 * for it.
3150 	 */
3151 	err = gen_pool_add_virt(hcd->localmem_pool, (unsigned long)local_mem,
3152 				dma, size, dev_to_node(hcd->self.sysdev));
3153 	if (err < 0) {
3154 		dev_err(hcd->self.sysdev, "gen_pool_add_virt failed with %d\n",
3155 			err);
3156 		return err;
3157 	}
3158 
3159 	return 0;
3160 }
3161 EXPORT_SYMBOL_GPL(usb_hcd_setup_local_mem);
3162 
3163 /*-------------------------------------------------------------------------*/
3164 
3165 #if IS_ENABLED(CONFIG_USB_MON)
3166 
3167 const struct usb_mon_operations *mon_ops;
3168 
3169 /*
3170  * The registration is unlocked.
3171  * We do it this way because we do not want to lock in hot paths.
3172  *
3173  * Notice that the code is minimally error-proof. Because usbmon needs
3174  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
3175  */
3176 
3177 int usb_mon_register(const struct usb_mon_operations *ops)
3178 {
3179 
3180 	if (mon_ops)
3181 		return -EBUSY;
3182 
3183 	mon_ops = ops;
3184 	mb();
3185 	return 0;
3186 }
3187 EXPORT_SYMBOL_GPL (usb_mon_register);
3188 
3189 void usb_mon_deregister (void)
3190 {
3191 
3192 	if (mon_ops == NULL) {
3193 		printk(KERN_ERR "USB: monitor was not registered\n");
3194 		return;
3195 	}
3196 	mon_ops = NULL;
3197 	mb();
3198 }
3199 EXPORT_SYMBOL_GPL (usb_mon_deregister);
3200 
3201 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
3202