xref: /openbmc/linux/drivers/usb/core/hcd.c (revision 4eb5928d)
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_CODE >> 16) & 0x0ff))
115 #define KERNEL_VER	bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff))
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  * Completions are called in_interrupt(), but they may or may not
751  * be in_irq().
752  */
753 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
754 {
755 	struct urb	*urb;
756 	int		length;
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 			urb->actual_length = length;
775 			memcpy(urb->transfer_buffer, buffer, length);
776 
777 			usb_hcd_unlink_urb_from_ep(hcd, urb);
778 			usb_hcd_giveback_urb(hcd, urb, 0);
779 		} else {
780 			length = 0;
781 			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
782 		}
783 		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
784 	}
785 
786 	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
787 	 * exceed that limit if HZ is 100. The math is more clunky than
788 	 * maybe expected, this is to make sure that all timers for USB devices
789 	 * fire at the same time to give the CPU a break in between */
790 	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
791 			(length == 0 && hcd->status_urb != NULL))
792 		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
793 }
794 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
795 
796 /* timer callback */
797 static void rh_timer_func (struct timer_list *t)
798 {
799 	struct usb_hcd *_hcd = from_timer(_hcd, t, rh_timer);
800 
801 	usb_hcd_poll_rh_status(_hcd);
802 }
803 
804 /*-------------------------------------------------------------------------*/
805 
806 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
807 {
808 	int		retval;
809 	unsigned long	flags;
810 	unsigned	len = 1 + (urb->dev->maxchild / 8);
811 
812 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
813 	if (hcd->status_urb || urb->transfer_buffer_length < len) {
814 		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
815 		retval = -EINVAL;
816 		goto done;
817 	}
818 
819 	retval = usb_hcd_link_urb_to_ep(hcd, urb);
820 	if (retval)
821 		goto done;
822 
823 	hcd->status_urb = urb;
824 	urb->hcpriv = hcd;	/* indicate it's queued */
825 	if (!hcd->uses_new_polling)
826 		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
827 
828 	/* If a status change has already occurred, report it ASAP */
829 	else if (HCD_POLL_PENDING(hcd))
830 		mod_timer(&hcd->rh_timer, jiffies);
831 	retval = 0;
832  done:
833 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
834 	return retval;
835 }
836 
837 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
838 {
839 	if (usb_endpoint_xfer_int(&urb->ep->desc))
840 		return rh_queue_status (hcd, urb);
841 	if (usb_endpoint_xfer_control(&urb->ep->desc))
842 		return rh_call_control (hcd, urb);
843 	return -EINVAL;
844 }
845 
846 /*-------------------------------------------------------------------------*/
847 
848 /* Unlinks of root-hub control URBs are legal, but they don't do anything
849  * since these URBs always execute synchronously.
850  */
851 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
852 {
853 	unsigned long	flags;
854 	int		rc;
855 
856 	spin_lock_irqsave(&hcd_root_hub_lock, flags);
857 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
858 	if (rc)
859 		goto done;
860 
861 	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
862 		;	/* Do nothing */
863 
864 	} else {				/* Status URB */
865 		if (!hcd->uses_new_polling)
866 			del_timer (&hcd->rh_timer);
867 		if (urb == hcd->status_urb) {
868 			hcd->status_urb = NULL;
869 			usb_hcd_unlink_urb_from_ep(hcd, urb);
870 			usb_hcd_giveback_urb(hcd, urb, status);
871 		}
872 	}
873  done:
874 	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
875 	return rc;
876 }
877 
878 
879 /*-------------------------------------------------------------------------*/
880 
881 /**
882  * usb_bus_init - shared initialization code
883  * @bus: the bus structure being initialized
884  *
885  * This code is used to initialize a usb_bus structure, memory for which is
886  * separately managed.
887  */
888 static void usb_bus_init (struct usb_bus *bus)
889 {
890 	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
891 
892 	bus->devnum_next = 1;
893 
894 	bus->root_hub = NULL;
895 	bus->busnum = -1;
896 	bus->bandwidth_allocated = 0;
897 	bus->bandwidth_int_reqs  = 0;
898 	bus->bandwidth_isoc_reqs = 0;
899 	mutex_init(&bus->devnum_next_mutex);
900 }
901 
902 /*-------------------------------------------------------------------------*/
903 
904 /**
905  * usb_register_bus - registers the USB host controller with the usb core
906  * @bus: pointer to the bus to register
907  * Context: !in_interrupt()
908  *
909  * Assigns a bus number, and links the controller into usbcore data
910  * structures so that it can be seen by scanning the bus list.
911  *
912  * Return: 0 if successful. A negative error code otherwise.
913  */
914 static int usb_register_bus(struct usb_bus *bus)
915 {
916 	int result = -E2BIG;
917 	int busnum;
918 
919 	mutex_lock(&usb_bus_idr_lock);
920 	busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL);
921 	if (busnum < 0) {
922 		pr_err("%s: failed to get bus number\n", usbcore_name);
923 		goto error_find_busnum;
924 	}
925 	bus->busnum = busnum;
926 	mutex_unlock(&usb_bus_idr_lock);
927 
928 	usb_notify_add_bus(bus);
929 
930 	dev_info (bus->controller, "new USB bus registered, assigned bus "
931 		  "number %d\n", bus->busnum);
932 	return 0;
933 
934 error_find_busnum:
935 	mutex_unlock(&usb_bus_idr_lock);
936 	return result;
937 }
938 
939 /**
940  * usb_deregister_bus - deregisters the USB host controller
941  * @bus: pointer to the bus to deregister
942  * Context: !in_interrupt()
943  *
944  * Recycles the bus number, and unlinks the controller from usbcore data
945  * structures so that it won't be seen by scanning the bus list.
946  */
947 static void usb_deregister_bus (struct usb_bus *bus)
948 {
949 	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
950 
951 	/*
952 	 * NOTE: make sure that all the devices are removed by the
953 	 * controller code, as well as having it call this when cleaning
954 	 * itself up
955 	 */
956 	mutex_lock(&usb_bus_idr_lock);
957 	idr_remove(&usb_bus_idr, bus->busnum);
958 	mutex_unlock(&usb_bus_idr_lock);
959 
960 	usb_notify_remove_bus(bus);
961 }
962 
963 /**
964  * register_root_hub - called by usb_add_hcd() to register a root hub
965  * @hcd: host controller for this root hub
966  *
967  * This function registers the root hub with the USB subsystem.  It sets up
968  * the device properly in the device tree and then calls usb_new_device()
969  * to register the usb device.  It also assigns the root hub's USB address
970  * (always 1).
971  *
972  * Return: 0 if successful. A negative error code otherwise.
973  */
974 static int register_root_hub(struct usb_hcd *hcd)
975 {
976 	struct device *parent_dev = hcd->self.controller;
977 	struct usb_device *usb_dev = hcd->self.root_hub;
978 	const int devnum = 1;
979 	int retval;
980 
981 	usb_dev->devnum = devnum;
982 	usb_dev->bus->devnum_next = devnum + 1;
983 	set_bit (devnum, usb_dev->bus->devmap.devicemap);
984 	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
985 
986 	mutex_lock(&usb_bus_idr_lock);
987 
988 	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
989 	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
990 	if (retval != sizeof usb_dev->descriptor) {
991 		mutex_unlock(&usb_bus_idr_lock);
992 		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
993 				dev_name(&usb_dev->dev), retval);
994 		return (retval < 0) ? retval : -EMSGSIZE;
995 	}
996 
997 	if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
998 		retval = usb_get_bos_descriptor(usb_dev);
999 		if (!retval) {
1000 			usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
1001 		} else if (usb_dev->speed >= USB_SPEED_SUPER) {
1002 			mutex_unlock(&usb_bus_idr_lock);
1003 			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1004 					dev_name(&usb_dev->dev), retval);
1005 			return retval;
1006 		}
1007 	}
1008 
1009 	retval = usb_new_device (usb_dev);
1010 	if (retval) {
1011 		dev_err (parent_dev, "can't register root hub for %s, %d\n",
1012 				dev_name(&usb_dev->dev), retval);
1013 	} else {
1014 		spin_lock_irq (&hcd_root_hub_lock);
1015 		hcd->rh_registered = 1;
1016 		spin_unlock_irq (&hcd_root_hub_lock);
1017 
1018 		/* Did the HC die before the root hub was registered? */
1019 		if (HCD_DEAD(hcd))
1020 			usb_hc_died (hcd);	/* This time clean up */
1021 	}
1022 	mutex_unlock(&usb_bus_idr_lock);
1023 
1024 	return retval;
1025 }
1026 
1027 /*
1028  * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1029  * @bus: the bus which the root hub belongs to
1030  * @portnum: the port which is being resumed
1031  *
1032  * HCDs should call this function when they know that a resume signal is
1033  * being sent to a root-hub port.  The root hub will be prevented from
1034  * going into autosuspend until usb_hcd_end_port_resume() is called.
1035  *
1036  * The bus's private lock must be held by the caller.
1037  */
1038 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1039 {
1040 	unsigned bit = 1 << portnum;
1041 
1042 	if (!(bus->resuming_ports & bit)) {
1043 		bus->resuming_ports |= bit;
1044 		pm_runtime_get_noresume(&bus->root_hub->dev);
1045 	}
1046 }
1047 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1048 
1049 /*
1050  * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1051  * @bus: the bus which the root hub belongs to
1052  * @portnum: the port which is being resumed
1053  *
1054  * HCDs should call this function when they know that a resume signal has
1055  * stopped being sent to a root-hub port.  The root hub will be allowed to
1056  * autosuspend again.
1057  *
1058  * The bus's private lock must be held by the caller.
1059  */
1060 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1061 {
1062 	unsigned bit = 1 << portnum;
1063 
1064 	if (bus->resuming_ports & bit) {
1065 		bus->resuming_ports &= ~bit;
1066 		pm_runtime_put_noidle(&bus->root_hub->dev);
1067 	}
1068 }
1069 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1070 
1071 /*-------------------------------------------------------------------------*/
1072 
1073 /**
1074  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1075  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1076  * @is_input: true iff the transaction sends data to the host
1077  * @isoc: true for isochronous transactions, false for interrupt ones
1078  * @bytecount: how many bytes in the transaction.
1079  *
1080  * Return: Approximate bus time in nanoseconds for a periodic transaction.
1081  *
1082  * Note:
1083  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1084  * scheduled in software, this function is only used for such scheduling.
1085  */
1086 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1087 {
1088 	unsigned long	tmp;
1089 
1090 	switch (speed) {
1091 	case USB_SPEED_LOW: 	/* INTR only */
1092 		if (is_input) {
1093 			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1094 			return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1095 		} else {
1096 			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1097 			return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1098 		}
1099 	case USB_SPEED_FULL:	/* ISOC or INTR */
1100 		if (isoc) {
1101 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1102 			return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1103 		} else {
1104 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1105 			return 9107L + BW_HOST_DELAY + tmp;
1106 		}
1107 	case USB_SPEED_HIGH:	/* ISOC or INTR */
1108 		/* FIXME adjust for input vs output */
1109 		if (isoc)
1110 			tmp = HS_NSECS_ISO (bytecount);
1111 		else
1112 			tmp = HS_NSECS (bytecount);
1113 		return tmp;
1114 	default:
1115 		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1116 		return -1;
1117 	}
1118 }
1119 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1120 
1121 
1122 /*-------------------------------------------------------------------------*/
1123 
1124 /*
1125  * Generic HC operations.
1126  */
1127 
1128 /*-------------------------------------------------------------------------*/
1129 
1130 /**
1131  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1132  * @hcd: host controller to which @urb was submitted
1133  * @urb: URB being submitted
1134  *
1135  * Host controller drivers should call this routine in their enqueue()
1136  * method.  The HCD's private spinlock must be held and interrupts must
1137  * be disabled.  The actions carried out here are required for URB
1138  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1139  *
1140  * Return: 0 for no error, otherwise a negative error code (in which case
1141  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1142  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1143  * the private spinlock and returning.
1144  */
1145 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1146 {
1147 	int		rc = 0;
1148 
1149 	spin_lock(&hcd_urb_list_lock);
1150 
1151 	/* Check that the URB isn't being killed */
1152 	if (unlikely(atomic_read(&urb->reject))) {
1153 		rc = -EPERM;
1154 		goto done;
1155 	}
1156 
1157 	if (unlikely(!urb->ep->enabled)) {
1158 		rc = -ENOENT;
1159 		goto done;
1160 	}
1161 
1162 	if (unlikely(!urb->dev->can_submit)) {
1163 		rc = -EHOSTUNREACH;
1164 		goto done;
1165 	}
1166 
1167 	/*
1168 	 * Check the host controller's state and add the URB to the
1169 	 * endpoint's queue.
1170 	 */
1171 	if (HCD_RH_RUNNING(hcd)) {
1172 		urb->unlinked = 0;
1173 		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1174 	} else {
1175 		rc = -ESHUTDOWN;
1176 		goto done;
1177 	}
1178  done:
1179 	spin_unlock(&hcd_urb_list_lock);
1180 	return rc;
1181 }
1182 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1183 
1184 /**
1185  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1186  * @hcd: host controller to which @urb was submitted
1187  * @urb: URB being checked for unlinkability
1188  * @status: error code to store in @urb if the unlink succeeds
1189  *
1190  * Host controller drivers should call this routine in their dequeue()
1191  * method.  The HCD's private spinlock must be held and interrupts must
1192  * be disabled.  The actions carried out here are required for making
1193  * sure than an unlink is valid.
1194  *
1195  * Return: 0 for no error, otherwise a negative error code (in which case
1196  * the dequeue() method must fail).  The possible error codes are:
1197  *
1198  *	-EIDRM: @urb was not submitted or has already completed.
1199  *		The completion function may not have been called yet.
1200  *
1201  *	-EBUSY: @urb has already been unlinked.
1202  */
1203 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1204 		int status)
1205 {
1206 	struct list_head	*tmp;
1207 
1208 	/* insist the urb is still queued */
1209 	list_for_each(tmp, &urb->ep->urb_list) {
1210 		if (tmp == &urb->urb_list)
1211 			break;
1212 	}
1213 	if (tmp != &urb->urb_list)
1214 		return -EIDRM;
1215 
1216 	/* Any status except -EINPROGRESS means something already started to
1217 	 * unlink this URB from the hardware.  So there's no more work to do.
1218 	 */
1219 	if (urb->unlinked)
1220 		return -EBUSY;
1221 	urb->unlinked = status;
1222 	return 0;
1223 }
1224 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1225 
1226 /**
1227  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1228  * @hcd: host controller to which @urb was submitted
1229  * @urb: URB being unlinked
1230  *
1231  * Host controller drivers should call this routine before calling
1232  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1233  * interrupts must be disabled.  The actions carried out here are required
1234  * for URB completion.
1235  */
1236 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1237 {
1238 	/* clear all state linking urb to this dev (and hcd) */
1239 	spin_lock(&hcd_urb_list_lock);
1240 	list_del_init(&urb->urb_list);
1241 	spin_unlock(&hcd_urb_list_lock);
1242 }
1243 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1244 
1245 /*
1246  * Some usb host controllers can only perform dma using a small SRAM area.
1247  * The usb core itself is however optimized for host controllers that can dma
1248  * using regular system memory - like pci devices doing bus mastering.
1249  *
1250  * To support host controllers with limited dma capabilities we provide dma
1251  * bounce buffers. This feature can be enabled by initializing
1252  * hcd->localmem_pool using usb_hcd_setup_local_mem().
1253  *
1254  * The initialized hcd->localmem_pool then tells the usb code to allocate all
1255  * data for dma using the genalloc API.
1256  *
1257  * So, to summarize...
1258  *
1259  * - We need "local" memory, canonical example being
1260  *   a small SRAM on a discrete controller being the
1261  *   only memory that the controller can read ...
1262  *   (a) "normal" kernel memory is no good, and
1263  *   (b) there's not enough to share
1264  *
1265  * - So we use that, even though the primary requirement
1266  *   is that the memory be "local" (hence addressable
1267  *   by that device), not "coherent".
1268  *
1269  */
1270 
1271 static int hcd_alloc_coherent(struct usb_bus *bus,
1272 			      gfp_t mem_flags, dma_addr_t *dma_handle,
1273 			      void **vaddr_handle, size_t size,
1274 			      enum dma_data_direction dir)
1275 {
1276 	unsigned char *vaddr;
1277 
1278 	if (*vaddr_handle == NULL) {
1279 		WARN_ON_ONCE(1);
1280 		return -EFAULT;
1281 	}
1282 
1283 	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1284 				 mem_flags, dma_handle);
1285 	if (!vaddr)
1286 		return -ENOMEM;
1287 
1288 	/*
1289 	 * Store the virtual address of the buffer at the end
1290 	 * of the allocated dma buffer. The size of the buffer
1291 	 * may be uneven so use unaligned functions instead
1292 	 * of just rounding up. It makes sense to optimize for
1293 	 * memory footprint over access speed since the amount
1294 	 * of memory available for dma may be limited.
1295 	 */
1296 	put_unaligned((unsigned long)*vaddr_handle,
1297 		      (unsigned long *)(vaddr + size));
1298 
1299 	if (dir == DMA_TO_DEVICE)
1300 		memcpy(vaddr, *vaddr_handle, size);
1301 
1302 	*vaddr_handle = vaddr;
1303 	return 0;
1304 }
1305 
1306 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1307 			      void **vaddr_handle, size_t size,
1308 			      enum dma_data_direction dir)
1309 {
1310 	unsigned char *vaddr = *vaddr_handle;
1311 
1312 	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1313 
1314 	if (dir == DMA_FROM_DEVICE)
1315 		memcpy(vaddr, *vaddr_handle, size);
1316 
1317 	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1318 
1319 	*vaddr_handle = vaddr;
1320 	*dma_handle = 0;
1321 }
1322 
1323 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1324 {
1325 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1326 	    (urb->transfer_flags & URB_SETUP_MAP_SINGLE))
1327 		dma_unmap_single(hcd->self.sysdev,
1328 				urb->setup_dma,
1329 				sizeof(struct usb_ctrlrequest),
1330 				DMA_TO_DEVICE);
1331 	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1332 		hcd_free_coherent(urb->dev->bus,
1333 				&urb->setup_dma,
1334 				(void **) &urb->setup_packet,
1335 				sizeof(struct usb_ctrlrequest),
1336 				DMA_TO_DEVICE);
1337 
1338 	/* Make it safe to call this routine more than once */
1339 	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1340 }
1341 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1342 
1343 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1344 {
1345 	if (hcd->driver->unmap_urb_for_dma)
1346 		hcd->driver->unmap_urb_for_dma(hcd, urb);
1347 	else
1348 		usb_hcd_unmap_urb_for_dma(hcd, urb);
1349 }
1350 
1351 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1352 {
1353 	enum dma_data_direction dir;
1354 
1355 	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1356 
1357 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1358 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1359 	    (urb->transfer_flags & URB_DMA_MAP_SG))
1360 		dma_unmap_sg(hcd->self.sysdev,
1361 				urb->sg,
1362 				urb->num_sgs,
1363 				dir);
1364 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1365 		 (urb->transfer_flags & URB_DMA_MAP_PAGE))
1366 		dma_unmap_page(hcd->self.sysdev,
1367 				urb->transfer_dma,
1368 				urb->transfer_buffer_length,
1369 				dir);
1370 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1371 		 (urb->transfer_flags & URB_DMA_MAP_SINGLE))
1372 		dma_unmap_single(hcd->self.sysdev,
1373 				urb->transfer_dma,
1374 				urb->transfer_buffer_length,
1375 				dir);
1376 	else if (urb->transfer_flags & URB_MAP_LOCAL)
1377 		hcd_free_coherent(urb->dev->bus,
1378 				&urb->transfer_dma,
1379 				&urb->transfer_buffer,
1380 				urb->transfer_buffer_length,
1381 				dir);
1382 
1383 	/* Make it safe to call this routine more than once */
1384 	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1385 			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1386 }
1387 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1388 
1389 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1390 			   gfp_t mem_flags)
1391 {
1392 	if (hcd->driver->map_urb_for_dma)
1393 		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1394 	else
1395 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1396 }
1397 
1398 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1399 			    gfp_t mem_flags)
1400 {
1401 	enum dma_data_direction dir;
1402 	int ret = 0;
1403 
1404 	/* Map the URB's buffers for DMA access.
1405 	 * Lower level HCD code should use *_dma exclusively,
1406 	 * unless it uses pio or talks to another transport,
1407 	 * or uses the provided scatter gather list for bulk.
1408 	 */
1409 
1410 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1411 		if (hcd->self.uses_pio_for_control)
1412 			return ret;
1413 		if (hcd->localmem_pool) {
1414 			ret = hcd_alloc_coherent(
1415 					urb->dev->bus, mem_flags,
1416 					&urb->setup_dma,
1417 					(void **)&urb->setup_packet,
1418 					sizeof(struct usb_ctrlrequest),
1419 					DMA_TO_DEVICE);
1420 			if (ret)
1421 				return ret;
1422 			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1423 		} else if (hcd_uses_dma(hcd)) {
1424 			if (object_is_on_stack(urb->setup_packet)) {
1425 				WARN_ONCE(1, "setup packet is on stack\n");
1426 				return -EAGAIN;
1427 			}
1428 
1429 			urb->setup_dma = dma_map_single(
1430 					hcd->self.sysdev,
1431 					urb->setup_packet,
1432 					sizeof(struct usb_ctrlrequest),
1433 					DMA_TO_DEVICE);
1434 			if (dma_mapping_error(hcd->self.sysdev,
1435 						urb->setup_dma))
1436 				return -EAGAIN;
1437 			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1438 		}
1439 	}
1440 
1441 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1442 	if (urb->transfer_buffer_length != 0
1443 	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1444 		if (hcd->localmem_pool) {
1445 			ret = hcd_alloc_coherent(
1446 					urb->dev->bus, mem_flags,
1447 					&urb->transfer_dma,
1448 					&urb->transfer_buffer,
1449 					urb->transfer_buffer_length,
1450 					dir);
1451 			if (ret == 0)
1452 				urb->transfer_flags |= URB_MAP_LOCAL;
1453 		} else if (hcd_uses_dma(hcd)) {
1454 			if (urb->num_sgs) {
1455 				int n;
1456 
1457 				/* We don't support sg for isoc transfers ! */
1458 				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1459 					WARN_ON(1);
1460 					return -EINVAL;
1461 				}
1462 
1463 				n = dma_map_sg(
1464 						hcd->self.sysdev,
1465 						urb->sg,
1466 						urb->num_sgs,
1467 						dir);
1468 				if (n <= 0)
1469 					ret = -EAGAIN;
1470 				else
1471 					urb->transfer_flags |= URB_DMA_MAP_SG;
1472 				urb->num_mapped_sgs = n;
1473 				if (n != urb->num_sgs)
1474 					urb->transfer_flags |=
1475 							URB_DMA_SG_COMBINED;
1476 			} else if (urb->sg) {
1477 				struct scatterlist *sg = urb->sg;
1478 				urb->transfer_dma = dma_map_page(
1479 						hcd->self.sysdev,
1480 						sg_page(sg),
1481 						sg->offset,
1482 						urb->transfer_buffer_length,
1483 						dir);
1484 				if (dma_mapping_error(hcd->self.sysdev,
1485 						urb->transfer_dma))
1486 					ret = -EAGAIN;
1487 				else
1488 					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1489 			} else if (object_is_on_stack(urb->transfer_buffer)) {
1490 				WARN_ONCE(1, "transfer buffer is on stack\n");
1491 				ret = -EAGAIN;
1492 			} else {
1493 				urb->transfer_dma = dma_map_single(
1494 						hcd->self.sysdev,
1495 						urb->transfer_buffer,
1496 						urb->transfer_buffer_length,
1497 						dir);
1498 				if (dma_mapping_error(hcd->self.sysdev,
1499 						urb->transfer_dma))
1500 					ret = -EAGAIN;
1501 				else
1502 					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1503 			}
1504 		}
1505 		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1506 				URB_SETUP_MAP_LOCAL)))
1507 			usb_hcd_unmap_urb_for_dma(hcd, urb);
1508 	}
1509 	return ret;
1510 }
1511 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1512 
1513 /*-------------------------------------------------------------------------*/
1514 
1515 /* may be called in any context with a valid urb->dev usecount
1516  * caller surrenders "ownership" of urb
1517  * expects usb_submit_urb() to have sanity checked and conditioned all
1518  * inputs in the urb
1519  */
1520 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1521 {
1522 	int			status;
1523 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1524 
1525 	/* increment urb's reference count as part of giving it to the HCD
1526 	 * (which will control it).  HCD guarantees that it either returns
1527 	 * an error or calls giveback(), but not both.
1528 	 */
1529 	usb_get_urb(urb);
1530 	atomic_inc(&urb->use_count);
1531 	atomic_inc(&urb->dev->urbnum);
1532 	usbmon_urb_submit(&hcd->self, urb);
1533 
1534 	/* NOTE requirements on root-hub callers (usbfs and the hub
1535 	 * driver, for now):  URBs' urb->transfer_buffer must be
1536 	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1537 	 * they could clobber root hub response data.  Also, control
1538 	 * URBs must be submitted in process context with interrupts
1539 	 * enabled.
1540 	 */
1541 
1542 	if (is_root_hub(urb->dev)) {
1543 		status = rh_urb_enqueue(hcd, urb);
1544 	} else {
1545 		status = map_urb_for_dma(hcd, urb, mem_flags);
1546 		if (likely(status == 0)) {
1547 			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1548 			if (unlikely(status))
1549 				unmap_urb_for_dma(hcd, urb);
1550 		}
1551 	}
1552 
1553 	if (unlikely(status)) {
1554 		usbmon_urb_submit_error(&hcd->self, urb, status);
1555 		urb->hcpriv = NULL;
1556 		INIT_LIST_HEAD(&urb->urb_list);
1557 		atomic_dec(&urb->use_count);
1558 		atomic_dec(&urb->dev->urbnum);
1559 		if (atomic_read(&urb->reject))
1560 			wake_up(&usb_kill_urb_queue);
1561 		usb_put_urb(urb);
1562 	}
1563 	return status;
1564 }
1565 
1566 /*-------------------------------------------------------------------------*/
1567 
1568 /* this makes the hcd giveback() the urb more quickly, by kicking it
1569  * off hardware queues (which may take a while) and returning it as
1570  * soon as practical.  we've already set up the urb's return status,
1571  * but we can't know if the callback completed already.
1572  */
1573 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1574 {
1575 	int		value;
1576 
1577 	if (is_root_hub(urb->dev))
1578 		value = usb_rh_urb_dequeue(hcd, urb, status);
1579 	else {
1580 
1581 		/* The only reason an HCD might fail this call is if
1582 		 * it has not yet fully queued the urb to begin with.
1583 		 * Such failures should be harmless. */
1584 		value = hcd->driver->urb_dequeue(hcd, urb, status);
1585 	}
1586 	return value;
1587 }
1588 
1589 /*
1590  * called in any context
1591  *
1592  * caller guarantees urb won't be recycled till both unlink()
1593  * and the urb's completion function return
1594  */
1595 int usb_hcd_unlink_urb (struct urb *urb, int status)
1596 {
1597 	struct usb_hcd		*hcd;
1598 	struct usb_device	*udev = urb->dev;
1599 	int			retval = -EIDRM;
1600 	unsigned long		flags;
1601 
1602 	/* Prevent the device and bus from going away while
1603 	 * the unlink is carried out.  If they are already gone
1604 	 * then urb->use_count must be 0, since disconnected
1605 	 * devices can't have any active URBs.
1606 	 */
1607 	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1608 	if (atomic_read(&urb->use_count) > 0) {
1609 		retval = 0;
1610 		usb_get_dev(udev);
1611 	}
1612 	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1613 	if (retval == 0) {
1614 		hcd = bus_to_hcd(urb->dev->bus);
1615 		retval = unlink1(hcd, urb, status);
1616 		if (retval == 0)
1617 			retval = -EINPROGRESS;
1618 		else if (retval != -EIDRM && retval != -EBUSY)
1619 			dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n",
1620 					urb, retval);
1621 		usb_put_dev(udev);
1622 	}
1623 	return retval;
1624 }
1625 
1626 /*-------------------------------------------------------------------------*/
1627 
1628 static void __usb_hcd_giveback_urb(struct urb *urb)
1629 {
1630 	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1631 	struct usb_anchor *anchor = urb->anchor;
1632 	int status = urb->unlinked;
1633 
1634 	urb->hcpriv = NULL;
1635 	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1636 	    urb->actual_length < urb->transfer_buffer_length &&
1637 	    !status))
1638 		status = -EREMOTEIO;
1639 
1640 	unmap_urb_for_dma(hcd, urb);
1641 	usbmon_urb_complete(&hcd->self, urb, status);
1642 	usb_anchor_suspend_wakeups(anchor);
1643 	usb_unanchor_urb(urb);
1644 	if (likely(status == 0))
1645 		usb_led_activity(USB_LED_EVENT_HOST);
1646 
1647 	/* pass ownership to the completion handler */
1648 	urb->status = status;
1649 	kcov_remote_start_usb((u64)urb->dev->bus->busnum);
1650 	urb->complete(urb);
1651 	kcov_remote_stop();
1652 
1653 	usb_anchor_resume_wakeups(anchor);
1654 	atomic_dec(&urb->use_count);
1655 	if (unlikely(atomic_read(&urb->reject)))
1656 		wake_up(&usb_kill_urb_queue);
1657 	usb_put_urb(urb);
1658 }
1659 
1660 static void usb_giveback_urb_bh(unsigned long param)
1661 {
1662 	struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param;
1663 	struct list_head local_list;
1664 
1665 	spin_lock_irq(&bh->lock);
1666 	bh->running = true;
1667  restart:
1668 	list_replace_init(&bh->head, &local_list);
1669 	spin_unlock_irq(&bh->lock);
1670 
1671 	while (!list_empty(&local_list)) {
1672 		struct urb *urb;
1673 
1674 		urb = list_entry(local_list.next, struct urb, urb_list);
1675 		list_del_init(&urb->urb_list);
1676 		bh->completing_ep = urb->ep;
1677 		__usb_hcd_giveback_urb(urb);
1678 		bh->completing_ep = NULL;
1679 	}
1680 
1681 	/* check if there are new URBs to giveback */
1682 	spin_lock_irq(&bh->lock);
1683 	if (!list_empty(&bh->head))
1684 		goto restart;
1685 	bh->running = false;
1686 	spin_unlock_irq(&bh->lock);
1687 }
1688 
1689 /**
1690  * usb_hcd_giveback_urb - return URB from HCD to device driver
1691  * @hcd: host controller returning the URB
1692  * @urb: urb being returned to the USB device driver.
1693  * @status: completion status code for the URB.
1694  * Context: in_interrupt()
1695  *
1696  * This hands the URB from HCD to its USB device driver, using its
1697  * completion function.  The HCD has freed all per-urb resources
1698  * (and is done using urb->hcpriv).  It also released all HCD locks;
1699  * the device driver won't cause problems if it frees, modifies,
1700  * or resubmits this URB.
1701  *
1702  * If @urb was unlinked, the value of @status will be overridden by
1703  * @urb->unlinked.  Erroneous short transfers are detected in case
1704  * the HCD hasn't checked for them.
1705  */
1706 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1707 {
1708 	struct giveback_urb_bh *bh;
1709 	bool running, high_prio_bh;
1710 
1711 	/* pass status to tasklet via unlinked */
1712 	if (likely(!urb->unlinked))
1713 		urb->unlinked = status;
1714 
1715 	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1716 		__usb_hcd_giveback_urb(urb);
1717 		return;
1718 	}
1719 
1720 	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
1721 		bh = &hcd->high_prio_bh;
1722 		high_prio_bh = true;
1723 	} else {
1724 		bh = &hcd->low_prio_bh;
1725 		high_prio_bh = false;
1726 	}
1727 
1728 	spin_lock(&bh->lock);
1729 	list_add_tail(&urb->urb_list, &bh->head);
1730 	running = bh->running;
1731 	spin_unlock(&bh->lock);
1732 
1733 	if (running)
1734 		;
1735 	else if (high_prio_bh)
1736 		tasklet_hi_schedule(&bh->bh);
1737 	else
1738 		tasklet_schedule(&bh->bh);
1739 }
1740 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1741 
1742 /*-------------------------------------------------------------------------*/
1743 
1744 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1745  * queue to drain completely.  The caller must first insure that no more
1746  * URBs can be submitted for this endpoint.
1747  */
1748 void usb_hcd_flush_endpoint(struct usb_device *udev,
1749 		struct usb_host_endpoint *ep)
1750 {
1751 	struct usb_hcd		*hcd;
1752 	struct urb		*urb;
1753 
1754 	if (!ep)
1755 		return;
1756 	might_sleep();
1757 	hcd = bus_to_hcd(udev->bus);
1758 
1759 	/* No more submits can occur */
1760 	spin_lock_irq(&hcd_urb_list_lock);
1761 rescan:
1762 	list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) {
1763 		int	is_in;
1764 
1765 		if (urb->unlinked)
1766 			continue;
1767 		usb_get_urb (urb);
1768 		is_in = usb_urb_dir_in(urb);
1769 		spin_unlock(&hcd_urb_list_lock);
1770 
1771 		/* kick hcd */
1772 		unlink1(hcd, urb, -ESHUTDOWN);
1773 		dev_dbg (hcd->self.controller,
1774 			"shutdown urb %pK ep%d%s-%s\n",
1775 			urb, usb_endpoint_num(&ep->desc),
1776 			is_in ? "in" : "out",
1777 			usb_ep_type_string(usb_endpoint_type(&ep->desc)));
1778 		usb_put_urb (urb);
1779 
1780 		/* list contents may have changed */
1781 		spin_lock(&hcd_urb_list_lock);
1782 		goto rescan;
1783 	}
1784 	spin_unlock_irq(&hcd_urb_list_lock);
1785 
1786 	/* Wait until the endpoint queue is completely empty */
1787 	while (!list_empty (&ep->urb_list)) {
1788 		spin_lock_irq(&hcd_urb_list_lock);
1789 
1790 		/* The list may have changed while we acquired the spinlock */
1791 		urb = NULL;
1792 		if (!list_empty (&ep->urb_list)) {
1793 			urb = list_entry (ep->urb_list.prev, struct urb,
1794 					urb_list);
1795 			usb_get_urb (urb);
1796 		}
1797 		spin_unlock_irq(&hcd_urb_list_lock);
1798 
1799 		if (urb) {
1800 			usb_kill_urb (urb);
1801 			usb_put_urb (urb);
1802 		}
1803 	}
1804 }
1805 
1806 /**
1807  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1808  *				the bus bandwidth
1809  * @udev: target &usb_device
1810  * @new_config: new configuration to install
1811  * @cur_alt: the current alternate interface setting
1812  * @new_alt: alternate interface setting that is being installed
1813  *
1814  * To change configurations, pass in the new configuration in new_config,
1815  * and pass NULL for cur_alt and new_alt.
1816  *
1817  * To reset a device's configuration (put the device in the ADDRESSED state),
1818  * pass in NULL for new_config, cur_alt, and new_alt.
1819  *
1820  * To change alternate interface settings, pass in NULL for new_config,
1821  * pass in the current alternate interface setting in cur_alt,
1822  * and pass in the new alternate interface setting in new_alt.
1823  *
1824  * Return: An error if the requested bandwidth change exceeds the
1825  * bus bandwidth or host controller internal resources.
1826  */
1827 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1828 		struct usb_host_config *new_config,
1829 		struct usb_host_interface *cur_alt,
1830 		struct usb_host_interface *new_alt)
1831 {
1832 	int num_intfs, i, j;
1833 	struct usb_host_interface *alt = NULL;
1834 	int ret = 0;
1835 	struct usb_hcd *hcd;
1836 	struct usb_host_endpoint *ep;
1837 
1838 	hcd = bus_to_hcd(udev->bus);
1839 	if (!hcd->driver->check_bandwidth)
1840 		return 0;
1841 
1842 	/* Configuration is being removed - set configuration 0 */
1843 	if (!new_config && !cur_alt) {
1844 		for (i = 1; i < 16; ++i) {
1845 			ep = udev->ep_out[i];
1846 			if (ep)
1847 				hcd->driver->drop_endpoint(hcd, udev, ep);
1848 			ep = udev->ep_in[i];
1849 			if (ep)
1850 				hcd->driver->drop_endpoint(hcd, udev, ep);
1851 		}
1852 		hcd->driver->check_bandwidth(hcd, udev);
1853 		return 0;
1854 	}
1855 	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1856 	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1857 	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1858 	 * ok to exclude it.
1859 	 */
1860 	if (new_config) {
1861 		num_intfs = new_config->desc.bNumInterfaces;
1862 		/* Remove endpoints (except endpoint 0, which is always on the
1863 		 * schedule) from the old config from the schedule
1864 		 */
1865 		for (i = 1; i < 16; ++i) {
1866 			ep = udev->ep_out[i];
1867 			if (ep) {
1868 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1869 				if (ret < 0)
1870 					goto reset;
1871 			}
1872 			ep = udev->ep_in[i];
1873 			if (ep) {
1874 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1875 				if (ret < 0)
1876 					goto reset;
1877 			}
1878 		}
1879 		for (i = 0; i < num_intfs; ++i) {
1880 			struct usb_host_interface *first_alt;
1881 			int iface_num;
1882 
1883 			first_alt = &new_config->intf_cache[i]->altsetting[0];
1884 			iface_num = first_alt->desc.bInterfaceNumber;
1885 			/* Set up endpoints for alternate interface setting 0 */
1886 			alt = usb_find_alt_setting(new_config, iface_num, 0);
1887 			if (!alt)
1888 				/* No alt setting 0? Pick the first setting. */
1889 				alt = first_alt;
1890 
1891 			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1892 				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1893 				if (ret < 0)
1894 					goto reset;
1895 			}
1896 		}
1897 	}
1898 	if (cur_alt && new_alt) {
1899 		struct usb_interface *iface = usb_ifnum_to_if(udev,
1900 				cur_alt->desc.bInterfaceNumber);
1901 
1902 		if (!iface)
1903 			return -EINVAL;
1904 		if (iface->resetting_device) {
1905 			/*
1906 			 * The USB core just reset the device, so the xHCI host
1907 			 * and the device will think alt setting 0 is installed.
1908 			 * However, the USB core will pass in the alternate
1909 			 * setting installed before the reset as cur_alt.  Dig
1910 			 * out the alternate setting 0 structure, or the first
1911 			 * alternate setting if a broken device doesn't have alt
1912 			 * setting 0.
1913 			 */
1914 			cur_alt = usb_altnum_to_altsetting(iface, 0);
1915 			if (!cur_alt)
1916 				cur_alt = &iface->altsetting[0];
1917 		}
1918 
1919 		/* Drop all the endpoints in the current alt setting */
1920 		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
1921 			ret = hcd->driver->drop_endpoint(hcd, udev,
1922 					&cur_alt->endpoint[i]);
1923 			if (ret < 0)
1924 				goto reset;
1925 		}
1926 		/* Add all the endpoints in the new alt setting */
1927 		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
1928 			ret = hcd->driver->add_endpoint(hcd, udev,
1929 					&new_alt->endpoint[i]);
1930 			if (ret < 0)
1931 				goto reset;
1932 		}
1933 	}
1934 	ret = hcd->driver->check_bandwidth(hcd, udev);
1935 reset:
1936 	if (ret < 0)
1937 		hcd->driver->reset_bandwidth(hcd, udev);
1938 	return ret;
1939 }
1940 
1941 /* Disables the endpoint: synchronizes with the hcd to make sure all
1942  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
1943  * have been called previously.  Use for set_configuration, set_interface,
1944  * driver removal, physical disconnect.
1945  *
1946  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
1947  * type, maxpacket size, toggle, halt status, and scheduling.
1948  */
1949 void usb_hcd_disable_endpoint(struct usb_device *udev,
1950 		struct usb_host_endpoint *ep)
1951 {
1952 	struct usb_hcd		*hcd;
1953 
1954 	might_sleep();
1955 	hcd = bus_to_hcd(udev->bus);
1956 	if (hcd->driver->endpoint_disable)
1957 		hcd->driver->endpoint_disable(hcd, ep);
1958 }
1959 
1960 /**
1961  * usb_hcd_reset_endpoint - reset host endpoint state
1962  * @udev: USB device.
1963  * @ep:   the endpoint to reset.
1964  *
1965  * Resets any host endpoint state such as the toggle bit, sequence
1966  * number and current window.
1967  */
1968 void usb_hcd_reset_endpoint(struct usb_device *udev,
1969 			    struct usb_host_endpoint *ep)
1970 {
1971 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1972 
1973 	if (hcd->driver->endpoint_reset)
1974 		hcd->driver->endpoint_reset(hcd, ep);
1975 	else {
1976 		int epnum = usb_endpoint_num(&ep->desc);
1977 		int is_out = usb_endpoint_dir_out(&ep->desc);
1978 		int is_control = usb_endpoint_xfer_control(&ep->desc);
1979 
1980 		usb_settoggle(udev, epnum, is_out, 0);
1981 		if (is_control)
1982 			usb_settoggle(udev, epnum, !is_out, 0);
1983 	}
1984 }
1985 
1986 /**
1987  * usb_alloc_streams - allocate bulk endpoint stream IDs.
1988  * @interface:		alternate setting that includes all endpoints.
1989  * @eps:		array of endpoints that need streams.
1990  * @num_eps:		number of endpoints in the array.
1991  * @num_streams:	number of streams to allocate.
1992  * @mem_flags:		flags hcd should use to allocate memory.
1993  *
1994  * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
1995  * Drivers may queue multiple transfers to different stream IDs, which may
1996  * complete in a different order than they were queued.
1997  *
1998  * Return: On success, the number of allocated streams. On failure, a negative
1999  * error code.
2000  */
2001 int usb_alloc_streams(struct usb_interface *interface,
2002 		struct usb_host_endpoint **eps, unsigned int num_eps,
2003 		unsigned int num_streams, gfp_t mem_flags)
2004 {
2005 	struct usb_hcd *hcd;
2006 	struct usb_device *dev;
2007 	int i, ret;
2008 
2009 	dev = interface_to_usbdev(interface);
2010 	hcd = bus_to_hcd(dev->bus);
2011 	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2012 		return -EINVAL;
2013 	if (dev->speed < USB_SPEED_SUPER)
2014 		return -EINVAL;
2015 	if (dev->state < USB_STATE_CONFIGURED)
2016 		return -ENODEV;
2017 
2018 	for (i = 0; i < num_eps; i++) {
2019 		/* Streams only apply to bulk endpoints. */
2020 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2021 			return -EINVAL;
2022 		/* Re-alloc is not allowed */
2023 		if (eps[i]->streams)
2024 			return -EINVAL;
2025 	}
2026 
2027 	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2028 			num_streams, mem_flags);
2029 	if (ret < 0)
2030 		return ret;
2031 
2032 	for (i = 0; i < num_eps; i++)
2033 		eps[i]->streams = ret;
2034 
2035 	return ret;
2036 }
2037 EXPORT_SYMBOL_GPL(usb_alloc_streams);
2038 
2039 /**
2040  * usb_free_streams - free bulk endpoint stream IDs.
2041  * @interface:	alternate setting that includes all endpoints.
2042  * @eps:	array of endpoints to remove streams from.
2043  * @num_eps:	number of endpoints in the array.
2044  * @mem_flags:	flags hcd should use to allocate memory.
2045  *
2046  * Reverts a group of bulk endpoints back to not using stream IDs.
2047  * Can fail if we are given bad arguments, or HCD is broken.
2048  *
2049  * Return: 0 on success. On failure, a negative error code.
2050  */
2051 int usb_free_streams(struct usb_interface *interface,
2052 		struct usb_host_endpoint **eps, unsigned int num_eps,
2053 		gfp_t mem_flags)
2054 {
2055 	struct usb_hcd *hcd;
2056 	struct usb_device *dev;
2057 	int i, ret;
2058 
2059 	dev = interface_to_usbdev(interface);
2060 	hcd = bus_to_hcd(dev->bus);
2061 	if (dev->speed < USB_SPEED_SUPER)
2062 		return -EINVAL;
2063 
2064 	/* Double-free is not allowed */
2065 	for (i = 0; i < num_eps; i++)
2066 		if (!eps[i] || !eps[i]->streams)
2067 			return -EINVAL;
2068 
2069 	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2070 	if (ret < 0)
2071 		return ret;
2072 
2073 	for (i = 0; i < num_eps; i++)
2074 		eps[i]->streams = 0;
2075 
2076 	return ret;
2077 }
2078 EXPORT_SYMBOL_GPL(usb_free_streams);
2079 
2080 /* Protect against drivers that try to unlink URBs after the device
2081  * is gone, by waiting until all unlinks for @udev are finished.
2082  * Since we don't currently track URBs by device, simply wait until
2083  * nothing is running in the locked region of usb_hcd_unlink_urb().
2084  */
2085 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2086 {
2087 	spin_lock_irq(&hcd_urb_unlink_lock);
2088 	spin_unlock_irq(&hcd_urb_unlink_lock);
2089 }
2090 
2091 /*-------------------------------------------------------------------------*/
2092 
2093 /* called in any context */
2094 int usb_hcd_get_frame_number (struct usb_device *udev)
2095 {
2096 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
2097 
2098 	if (!HCD_RH_RUNNING(hcd))
2099 		return -ESHUTDOWN;
2100 	return hcd->driver->get_frame_number (hcd);
2101 }
2102 
2103 /*-------------------------------------------------------------------------*/
2104 
2105 #ifdef	CONFIG_PM
2106 
2107 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2108 {
2109 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2110 	int		status;
2111 	int		old_state = hcd->state;
2112 
2113 	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2114 			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2115 			rhdev->do_remote_wakeup);
2116 	if (HCD_DEAD(hcd)) {
2117 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2118 		return 0;
2119 	}
2120 
2121 	if (!hcd->driver->bus_suspend) {
2122 		status = -ENOENT;
2123 	} else {
2124 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2125 		hcd->state = HC_STATE_QUIESCING;
2126 		status = hcd->driver->bus_suspend(hcd);
2127 	}
2128 	if (status == 0) {
2129 		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2130 		hcd->state = HC_STATE_SUSPENDED;
2131 
2132 		if (!PMSG_IS_AUTO(msg))
2133 			usb_phy_roothub_suspend(hcd->self.sysdev,
2134 						hcd->phy_roothub);
2135 
2136 		/* Did we race with a root-hub wakeup event? */
2137 		if (rhdev->do_remote_wakeup) {
2138 			char	buffer[6];
2139 
2140 			status = hcd->driver->hub_status_data(hcd, buffer);
2141 			if (status != 0) {
2142 				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2143 				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2144 				status = -EBUSY;
2145 			}
2146 		}
2147 	} else {
2148 		spin_lock_irq(&hcd_root_hub_lock);
2149 		if (!HCD_DEAD(hcd)) {
2150 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2151 			hcd->state = old_state;
2152 		}
2153 		spin_unlock_irq(&hcd_root_hub_lock);
2154 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2155 				"suspend", status);
2156 	}
2157 	return status;
2158 }
2159 
2160 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2161 {
2162 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2163 	int		status;
2164 	int		old_state = hcd->state;
2165 
2166 	dev_dbg(&rhdev->dev, "usb %sresume\n",
2167 			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2168 	if (HCD_DEAD(hcd)) {
2169 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2170 		return 0;
2171 	}
2172 
2173 	if (!PMSG_IS_AUTO(msg)) {
2174 		status = usb_phy_roothub_resume(hcd->self.sysdev,
2175 						hcd->phy_roothub);
2176 		if (status)
2177 			return status;
2178 	}
2179 
2180 	if (!hcd->driver->bus_resume)
2181 		return -ENOENT;
2182 	if (HCD_RH_RUNNING(hcd))
2183 		return 0;
2184 
2185 	hcd->state = HC_STATE_RESUMING;
2186 	status = hcd->driver->bus_resume(hcd);
2187 	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2188 	if (status == 0)
2189 		status = usb_phy_roothub_calibrate(hcd->phy_roothub);
2190 
2191 	if (status == 0) {
2192 		struct usb_device *udev;
2193 		int port1;
2194 
2195 		spin_lock_irq(&hcd_root_hub_lock);
2196 		if (!HCD_DEAD(hcd)) {
2197 			usb_set_device_state(rhdev, rhdev->actconfig
2198 					? USB_STATE_CONFIGURED
2199 					: USB_STATE_ADDRESS);
2200 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2201 			hcd->state = HC_STATE_RUNNING;
2202 		}
2203 		spin_unlock_irq(&hcd_root_hub_lock);
2204 
2205 		/*
2206 		 * Check whether any of the enabled ports on the root hub are
2207 		 * unsuspended.  If they are then a TRSMRCY delay is needed
2208 		 * (this is what the USB-2 spec calls a "global resume").
2209 		 * Otherwise we can skip the delay.
2210 		 */
2211 		usb_hub_for_each_child(rhdev, port1, udev) {
2212 			if (udev->state != USB_STATE_NOTATTACHED &&
2213 					!udev->port_is_suspended) {
2214 				usleep_range(10000, 11000);	/* TRSMRCY */
2215 				break;
2216 			}
2217 		}
2218 	} else {
2219 		hcd->state = old_state;
2220 		usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub);
2221 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2222 				"resume", status);
2223 		if (status != -ESHUTDOWN)
2224 			usb_hc_died(hcd);
2225 	}
2226 	return status;
2227 }
2228 
2229 /* Workqueue routine for root-hub remote wakeup */
2230 static void hcd_resume_work(struct work_struct *work)
2231 {
2232 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2233 	struct usb_device *udev = hcd->self.root_hub;
2234 
2235 	usb_remote_wakeup(udev);
2236 }
2237 
2238 /**
2239  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2240  * @hcd: host controller for this root hub
2241  *
2242  * The USB host controller calls this function when its root hub is
2243  * suspended (with the remote wakeup feature enabled) and a remote
2244  * wakeup request is received.  The routine submits a workqueue request
2245  * to resume the root hub (that is, manage its downstream ports again).
2246  */
2247 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2248 {
2249 	unsigned long flags;
2250 
2251 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2252 	if (hcd->rh_registered) {
2253 		pm_wakeup_event(&hcd->self.root_hub->dev, 0);
2254 		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2255 		queue_work(pm_wq, &hcd->wakeup_work);
2256 	}
2257 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2258 }
2259 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2260 
2261 #endif	/* CONFIG_PM */
2262 
2263 /*-------------------------------------------------------------------------*/
2264 
2265 #ifdef	CONFIG_USB_OTG
2266 
2267 /**
2268  * usb_bus_start_enum - start immediate enumeration (for OTG)
2269  * @bus: the bus (must use hcd framework)
2270  * @port_num: 1-based number of port; usually bus->otg_port
2271  * Context: in_interrupt()
2272  *
2273  * Starts enumeration, with an immediate reset followed later by
2274  * hub_wq identifying and possibly configuring the device.
2275  * This is needed by OTG controller drivers, where it helps meet
2276  * HNP protocol timing requirements for starting a port reset.
2277  *
2278  * Return: 0 if successful.
2279  */
2280 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2281 {
2282 	struct usb_hcd		*hcd;
2283 	int			status = -EOPNOTSUPP;
2284 
2285 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2286 	 * boards with root hubs hooked up to internal devices (instead of
2287 	 * just the OTG port) may need more attention to resetting...
2288 	 */
2289 	hcd = bus_to_hcd(bus);
2290 	if (port_num && hcd->driver->start_port_reset)
2291 		status = hcd->driver->start_port_reset(hcd, port_num);
2292 
2293 	/* allocate hub_wq shortly after (first) root port reset finishes;
2294 	 * it may issue others, until at least 50 msecs have passed.
2295 	 */
2296 	if (status == 0)
2297 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2298 	return status;
2299 }
2300 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2301 
2302 #endif
2303 
2304 /*-------------------------------------------------------------------------*/
2305 
2306 /**
2307  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2308  * @irq: the IRQ being raised
2309  * @__hcd: pointer to the HCD whose IRQ is being signaled
2310  *
2311  * If the controller isn't HALTed, calls the driver's irq handler.
2312  * Checks whether the controller is now dead.
2313  *
2314  * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2315  */
2316 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2317 {
2318 	struct usb_hcd		*hcd = __hcd;
2319 	irqreturn_t		rc;
2320 
2321 	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2322 		rc = IRQ_NONE;
2323 	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2324 		rc = IRQ_NONE;
2325 	else
2326 		rc = IRQ_HANDLED;
2327 
2328 	return rc;
2329 }
2330 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2331 
2332 /*-------------------------------------------------------------------------*/
2333 
2334 /* Workqueue routine for when the root-hub has died. */
2335 static void hcd_died_work(struct work_struct *work)
2336 {
2337 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, died_work);
2338 	static char *env[] = {
2339 		"ERROR=DEAD",
2340 		NULL
2341 	};
2342 
2343 	/* Notify user space that the host controller has died */
2344 	kobject_uevent_env(&hcd->self.root_hub->dev.kobj, KOBJ_OFFLINE, env);
2345 }
2346 
2347 /**
2348  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2349  * @hcd: pointer to the HCD representing the controller
2350  *
2351  * This is called by bus glue to report a USB host controller that died
2352  * while operations may still have been pending.  It's called automatically
2353  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2354  *
2355  * Only call this function with the primary HCD.
2356  */
2357 void usb_hc_died (struct usb_hcd *hcd)
2358 {
2359 	unsigned long flags;
2360 
2361 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2362 
2363 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2364 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2365 	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2366 	if (hcd->rh_registered) {
2367 		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2368 
2369 		/* make hub_wq clean up old urbs and devices */
2370 		usb_set_device_state (hcd->self.root_hub,
2371 				USB_STATE_NOTATTACHED);
2372 		usb_kick_hub_wq(hcd->self.root_hub);
2373 	}
2374 	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2375 		hcd = hcd->shared_hcd;
2376 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2377 		set_bit(HCD_FLAG_DEAD, &hcd->flags);
2378 		if (hcd->rh_registered) {
2379 			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2380 
2381 			/* make hub_wq clean up old urbs and devices */
2382 			usb_set_device_state(hcd->self.root_hub,
2383 					USB_STATE_NOTATTACHED);
2384 			usb_kick_hub_wq(hcd->self.root_hub);
2385 		}
2386 	}
2387 
2388 	/* Handle the case where this function gets called with a shared HCD */
2389 	if (usb_hcd_is_primary_hcd(hcd))
2390 		schedule_work(&hcd->died_work);
2391 	else
2392 		schedule_work(&hcd->primary_hcd->died_work);
2393 
2394 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2395 	/* Make sure that the other roothub is also deallocated. */
2396 }
2397 EXPORT_SYMBOL_GPL (usb_hc_died);
2398 
2399 /*-------------------------------------------------------------------------*/
2400 
2401 static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2402 {
2403 
2404 	spin_lock_init(&bh->lock);
2405 	INIT_LIST_HEAD(&bh->head);
2406 	tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh);
2407 }
2408 
2409 struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
2410 		struct device *sysdev, struct device *dev, const char *bus_name,
2411 		struct usb_hcd *primary_hcd)
2412 {
2413 	struct usb_hcd *hcd;
2414 
2415 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2416 	if (!hcd)
2417 		return NULL;
2418 	if (primary_hcd == NULL) {
2419 		hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex),
2420 				GFP_KERNEL);
2421 		if (!hcd->address0_mutex) {
2422 			kfree(hcd);
2423 			dev_dbg(dev, "hcd address0 mutex alloc failed\n");
2424 			return NULL;
2425 		}
2426 		mutex_init(hcd->address0_mutex);
2427 		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2428 				GFP_KERNEL);
2429 		if (!hcd->bandwidth_mutex) {
2430 			kfree(hcd->address0_mutex);
2431 			kfree(hcd);
2432 			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2433 			return NULL;
2434 		}
2435 		mutex_init(hcd->bandwidth_mutex);
2436 		dev_set_drvdata(dev, hcd);
2437 	} else {
2438 		mutex_lock(&usb_port_peer_mutex);
2439 		hcd->address0_mutex = primary_hcd->address0_mutex;
2440 		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2441 		hcd->primary_hcd = primary_hcd;
2442 		primary_hcd->primary_hcd = primary_hcd;
2443 		hcd->shared_hcd = primary_hcd;
2444 		primary_hcd->shared_hcd = hcd;
2445 		mutex_unlock(&usb_port_peer_mutex);
2446 	}
2447 
2448 	kref_init(&hcd->kref);
2449 
2450 	usb_bus_init(&hcd->self);
2451 	hcd->self.controller = dev;
2452 	hcd->self.sysdev = sysdev;
2453 	hcd->self.bus_name = bus_name;
2454 
2455 	timer_setup(&hcd->rh_timer, rh_timer_func, 0);
2456 #ifdef CONFIG_PM
2457 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2458 #endif
2459 
2460 	INIT_WORK(&hcd->died_work, hcd_died_work);
2461 
2462 	hcd->driver = driver;
2463 	hcd->speed = driver->flags & HCD_MASK;
2464 	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2465 			"USB Host Controller";
2466 	return hcd;
2467 }
2468 EXPORT_SYMBOL_GPL(__usb_create_hcd);
2469 
2470 /**
2471  * usb_create_shared_hcd - create and initialize an HCD structure
2472  * @driver: HC driver that will use this hcd
2473  * @dev: device for this HC, stored in hcd->self.controller
2474  * @bus_name: value to store in hcd->self.bus_name
2475  * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2476  *              PCI device.  Only allocate certain resources for the primary HCD
2477  * Context: !in_interrupt()
2478  *
2479  * Allocate a struct usb_hcd, with extra space at the end for the
2480  * HC driver's private data.  Initialize the generic members of the
2481  * hcd structure.
2482  *
2483  * Return: On success, a pointer to the created and initialized HCD structure.
2484  * On failure (e.g. if memory is unavailable), %NULL.
2485  */
2486 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2487 		struct device *dev, const char *bus_name,
2488 		struct usb_hcd *primary_hcd)
2489 {
2490 	return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd);
2491 }
2492 EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2493 
2494 /**
2495  * usb_create_hcd - create and initialize an HCD structure
2496  * @driver: HC driver that will use this hcd
2497  * @dev: device for this HC, stored in hcd->self.controller
2498  * @bus_name: value to store in hcd->self.bus_name
2499  * Context: !in_interrupt()
2500  *
2501  * Allocate a struct usb_hcd, with extra space at the end for the
2502  * HC driver's private data.  Initialize the generic members of the
2503  * hcd structure.
2504  *
2505  * Return: On success, a pointer to the created and initialized HCD
2506  * structure. On failure (e.g. if memory is unavailable), %NULL.
2507  */
2508 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2509 		struct device *dev, const char *bus_name)
2510 {
2511 	return __usb_create_hcd(driver, dev, dev, bus_name, NULL);
2512 }
2513 EXPORT_SYMBOL_GPL(usb_create_hcd);
2514 
2515 /*
2516  * Roothubs that share one PCI device must also share the bandwidth mutex.
2517  * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2518  * deallocated.
2519  *
2520  * Make sure to deallocate the bandwidth_mutex only when the last HCD is
2521  * freed.  When hcd_release() is called for either hcd in a peer set,
2522  * invalidate the peer's ->shared_hcd and ->primary_hcd pointers.
2523  */
2524 static void hcd_release(struct kref *kref)
2525 {
2526 	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2527 
2528 	mutex_lock(&usb_port_peer_mutex);
2529 	if (hcd->shared_hcd) {
2530 		struct usb_hcd *peer = hcd->shared_hcd;
2531 
2532 		peer->shared_hcd = NULL;
2533 		peer->primary_hcd = NULL;
2534 	} else {
2535 		kfree(hcd->address0_mutex);
2536 		kfree(hcd->bandwidth_mutex);
2537 	}
2538 	mutex_unlock(&usb_port_peer_mutex);
2539 	kfree(hcd);
2540 }
2541 
2542 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2543 {
2544 	if (hcd)
2545 		kref_get (&hcd->kref);
2546 	return hcd;
2547 }
2548 EXPORT_SYMBOL_GPL(usb_get_hcd);
2549 
2550 void usb_put_hcd (struct usb_hcd *hcd)
2551 {
2552 	if (hcd)
2553 		kref_put (&hcd->kref, hcd_release);
2554 }
2555 EXPORT_SYMBOL_GPL(usb_put_hcd);
2556 
2557 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2558 {
2559 	if (!hcd->primary_hcd)
2560 		return 1;
2561 	return hcd == hcd->primary_hcd;
2562 }
2563 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2564 
2565 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2566 {
2567 	if (!hcd->driver->find_raw_port_number)
2568 		return port1;
2569 
2570 	return hcd->driver->find_raw_port_number(hcd, port1);
2571 }
2572 
2573 static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2574 		unsigned int irqnum, unsigned long irqflags)
2575 {
2576 	int retval;
2577 
2578 	if (hcd->driver->irq) {
2579 
2580 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2581 				hcd->driver->description, hcd->self.busnum);
2582 		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2583 				hcd->irq_descr, hcd);
2584 		if (retval != 0) {
2585 			dev_err(hcd->self.controller,
2586 					"request interrupt %d failed\n",
2587 					irqnum);
2588 			return retval;
2589 		}
2590 		hcd->irq = irqnum;
2591 		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2592 				(hcd->driver->flags & HCD_MEMORY) ?
2593 					"io mem" : "io base",
2594 					(unsigned long long)hcd->rsrc_start);
2595 	} else {
2596 		hcd->irq = 0;
2597 		if (hcd->rsrc_start)
2598 			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2599 					(hcd->driver->flags & HCD_MEMORY) ?
2600 					"io mem" : "io base",
2601 					(unsigned long long)hcd->rsrc_start);
2602 	}
2603 	return 0;
2604 }
2605 
2606 /*
2607  * Before we free this root hub, flush in-flight peering attempts
2608  * and disable peer lookups
2609  */
2610 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2611 {
2612 	struct usb_device *rhdev;
2613 
2614 	mutex_lock(&usb_port_peer_mutex);
2615 	rhdev = hcd->self.root_hub;
2616 	hcd->self.root_hub = NULL;
2617 	mutex_unlock(&usb_port_peer_mutex);
2618 	usb_put_dev(rhdev);
2619 }
2620 
2621 /**
2622  * usb_add_hcd - finish generic HCD structure initialization and register
2623  * @hcd: the usb_hcd structure to initialize
2624  * @irqnum: Interrupt line to allocate
2625  * @irqflags: Interrupt type flags
2626  *
2627  * Finish the remaining parts of generic HCD initialization: allocate the
2628  * buffers of consistent memory, register the bus, request the IRQ line,
2629  * and call the driver's reset() and start() routines.
2630  */
2631 int usb_add_hcd(struct usb_hcd *hcd,
2632 		unsigned int irqnum, unsigned long irqflags)
2633 {
2634 	int retval;
2635 	struct usb_device *rhdev;
2636 
2637 	if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) {
2638 		hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev);
2639 		if (IS_ERR(hcd->phy_roothub))
2640 			return PTR_ERR(hcd->phy_roothub);
2641 
2642 		retval = usb_phy_roothub_init(hcd->phy_roothub);
2643 		if (retval)
2644 			return retval;
2645 
2646 		retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2647 						  PHY_MODE_USB_HOST_SS);
2648 		if (retval)
2649 			retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2650 							  PHY_MODE_USB_HOST);
2651 		if (retval)
2652 			goto err_usb_phy_roothub_power_on;
2653 
2654 		retval = usb_phy_roothub_power_on(hcd->phy_roothub);
2655 		if (retval)
2656 			goto err_usb_phy_roothub_power_on;
2657 	}
2658 
2659 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2660 
2661 	switch (authorized_default) {
2662 	case USB_AUTHORIZE_NONE:
2663 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_NONE;
2664 		break;
2665 
2666 	case USB_AUTHORIZE_ALL:
2667 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_ALL;
2668 		break;
2669 
2670 	case USB_AUTHORIZE_INTERNAL:
2671 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_INTERNAL;
2672 		break;
2673 
2674 	case USB_AUTHORIZE_WIRED:
2675 	default:
2676 		hcd->dev_policy = hcd->wireless ?
2677 			USB_DEVICE_AUTHORIZE_NONE : USB_DEVICE_AUTHORIZE_ALL;
2678 		break;
2679 	}
2680 
2681 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2682 
2683 	/* per default all interfaces are authorized */
2684 	set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
2685 
2686 	/* HC is in reset state, but accessible.  Now do the one-time init,
2687 	 * bottom up so that hcds can customize the root hubs before hub_wq
2688 	 * starts talking to them.  (Note, bus id is assigned early too.)
2689 	 */
2690 	retval = hcd_buffer_create(hcd);
2691 	if (retval != 0) {
2692 		dev_dbg(hcd->self.sysdev, "pool alloc failed\n");
2693 		goto err_create_buf;
2694 	}
2695 
2696 	retval = usb_register_bus(&hcd->self);
2697 	if (retval < 0)
2698 		goto err_register_bus;
2699 
2700 	rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2701 	if (rhdev == NULL) {
2702 		dev_err(hcd->self.sysdev, "unable to allocate root hub\n");
2703 		retval = -ENOMEM;
2704 		goto err_allocate_root_hub;
2705 	}
2706 	mutex_lock(&usb_port_peer_mutex);
2707 	hcd->self.root_hub = rhdev;
2708 	mutex_unlock(&usb_port_peer_mutex);
2709 
2710 	rhdev->rx_lanes = 1;
2711 	rhdev->tx_lanes = 1;
2712 
2713 	switch (hcd->speed) {
2714 	case HCD_USB11:
2715 		rhdev->speed = USB_SPEED_FULL;
2716 		break;
2717 	case HCD_USB2:
2718 		rhdev->speed = USB_SPEED_HIGH;
2719 		break;
2720 	case HCD_USB25:
2721 		rhdev->speed = USB_SPEED_WIRELESS;
2722 		break;
2723 	case HCD_USB3:
2724 		rhdev->speed = USB_SPEED_SUPER;
2725 		break;
2726 	case HCD_USB32:
2727 		rhdev->rx_lanes = 2;
2728 		rhdev->tx_lanes = 2;
2729 		fallthrough;
2730 	case HCD_USB31:
2731 		rhdev->speed = USB_SPEED_SUPER_PLUS;
2732 		break;
2733 	default:
2734 		retval = -EINVAL;
2735 		goto err_set_rh_speed;
2736 	}
2737 
2738 	/* wakeup flag init defaults to "everything works" for root hubs,
2739 	 * but drivers can override it in reset() if needed, along with
2740 	 * recording the overall controller's system wakeup capability.
2741 	 */
2742 	device_set_wakeup_capable(&rhdev->dev, 1);
2743 
2744 	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2745 	 * registered.  But since the controller can die at any time,
2746 	 * let's initialize the flag before touching the hardware.
2747 	 */
2748 	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2749 
2750 	/* "reset" is misnamed; its role is now one-time init. the controller
2751 	 * should already have been reset (and boot firmware kicked off etc).
2752 	 */
2753 	if (hcd->driver->reset) {
2754 		retval = hcd->driver->reset(hcd);
2755 		if (retval < 0) {
2756 			dev_err(hcd->self.controller, "can't setup: %d\n",
2757 					retval);
2758 			goto err_hcd_driver_setup;
2759 		}
2760 	}
2761 	hcd->rh_pollable = 1;
2762 
2763 	retval = usb_phy_roothub_calibrate(hcd->phy_roothub);
2764 	if (retval)
2765 		goto err_hcd_driver_setup;
2766 
2767 	/* NOTE: root hub and controller capabilities may not be the same */
2768 	if (device_can_wakeup(hcd->self.controller)
2769 			&& device_can_wakeup(&hcd->self.root_hub->dev))
2770 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2771 
2772 	/* initialize tasklets */
2773 	init_giveback_urb_bh(&hcd->high_prio_bh);
2774 	init_giveback_urb_bh(&hcd->low_prio_bh);
2775 
2776 	/* enable irqs just before we start the controller,
2777 	 * if the BIOS provides legacy PCI irqs.
2778 	 */
2779 	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2780 		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2781 		if (retval)
2782 			goto err_request_irq;
2783 	}
2784 
2785 	hcd->state = HC_STATE_RUNNING;
2786 	retval = hcd->driver->start(hcd);
2787 	if (retval < 0) {
2788 		dev_err(hcd->self.controller, "startup error %d\n", retval);
2789 		goto err_hcd_driver_start;
2790 	}
2791 
2792 	/* starting here, usbcore will pay attention to this root hub */
2793 	retval = register_root_hub(hcd);
2794 	if (retval != 0)
2795 		goto err_register_root_hub;
2796 
2797 	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2798 		usb_hcd_poll_rh_status(hcd);
2799 
2800 	return retval;
2801 
2802 err_register_root_hub:
2803 	hcd->rh_pollable = 0;
2804 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2805 	del_timer_sync(&hcd->rh_timer);
2806 	hcd->driver->stop(hcd);
2807 	hcd->state = HC_STATE_HALT;
2808 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2809 	del_timer_sync(&hcd->rh_timer);
2810 err_hcd_driver_start:
2811 	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2812 		free_irq(irqnum, hcd);
2813 err_request_irq:
2814 err_hcd_driver_setup:
2815 err_set_rh_speed:
2816 	usb_put_invalidate_rhdev(hcd);
2817 err_allocate_root_hub:
2818 	usb_deregister_bus(&hcd->self);
2819 err_register_bus:
2820 	hcd_buffer_destroy(hcd);
2821 err_create_buf:
2822 	usb_phy_roothub_power_off(hcd->phy_roothub);
2823 err_usb_phy_roothub_power_on:
2824 	usb_phy_roothub_exit(hcd->phy_roothub);
2825 
2826 	return retval;
2827 }
2828 EXPORT_SYMBOL_GPL(usb_add_hcd);
2829 
2830 /**
2831  * usb_remove_hcd - shutdown processing for generic HCDs
2832  * @hcd: the usb_hcd structure to remove
2833  * Context: !in_interrupt()
2834  *
2835  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2836  * invoking the HCD's stop() method.
2837  */
2838 void usb_remove_hcd(struct usb_hcd *hcd)
2839 {
2840 	struct usb_device *rhdev = hcd->self.root_hub;
2841 
2842 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2843 
2844 	usb_get_dev(rhdev);
2845 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2846 	if (HC_IS_RUNNING (hcd->state))
2847 		hcd->state = HC_STATE_QUIESCING;
2848 
2849 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2850 	spin_lock_irq (&hcd_root_hub_lock);
2851 	hcd->rh_registered = 0;
2852 	spin_unlock_irq (&hcd_root_hub_lock);
2853 
2854 #ifdef CONFIG_PM
2855 	cancel_work_sync(&hcd->wakeup_work);
2856 #endif
2857 	cancel_work_sync(&hcd->died_work);
2858 
2859 	mutex_lock(&usb_bus_idr_lock);
2860 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2861 	mutex_unlock(&usb_bus_idr_lock);
2862 
2863 	/*
2864 	 * tasklet_kill() isn't needed here because:
2865 	 * - driver's disconnect() called from usb_disconnect() should
2866 	 *   make sure its URBs are completed during the disconnect()
2867 	 *   callback
2868 	 *
2869 	 * - it is too late to run complete() here since driver may have
2870 	 *   been removed already now
2871 	 */
2872 
2873 	/* Prevent any more root-hub status calls from the timer.
2874 	 * The HCD might still restart the timer (if a port status change
2875 	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
2876 	 * the hub_status_data() callback.
2877 	 */
2878 	hcd->rh_pollable = 0;
2879 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2880 	del_timer_sync(&hcd->rh_timer);
2881 
2882 	hcd->driver->stop(hcd);
2883 	hcd->state = HC_STATE_HALT;
2884 
2885 	/* In case the HCD restarted the timer, stop it again. */
2886 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2887 	del_timer_sync(&hcd->rh_timer);
2888 
2889 	if (usb_hcd_is_primary_hcd(hcd)) {
2890 		if (hcd->irq > 0)
2891 			free_irq(hcd->irq, hcd);
2892 	}
2893 
2894 	usb_deregister_bus(&hcd->self);
2895 	hcd_buffer_destroy(hcd);
2896 
2897 	usb_phy_roothub_power_off(hcd->phy_roothub);
2898 	usb_phy_roothub_exit(hcd->phy_roothub);
2899 
2900 	usb_put_invalidate_rhdev(hcd);
2901 	hcd->flags = 0;
2902 }
2903 EXPORT_SYMBOL_GPL(usb_remove_hcd);
2904 
2905 void
2906 usb_hcd_platform_shutdown(struct platform_device *dev)
2907 {
2908 	struct usb_hcd *hcd = platform_get_drvdata(dev);
2909 
2910 	/* No need for pm_runtime_put(), we're shutting down */
2911 	pm_runtime_get_sync(&dev->dev);
2912 
2913 	if (hcd->driver->shutdown)
2914 		hcd->driver->shutdown(hcd);
2915 }
2916 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
2917 
2918 int usb_hcd_setup_local_mem(struct usb_hcd *hcd, phys_addr_t phys_addr,
2919 			    dma_addr_t dma, size_t size)
2920 {
2921 	int err;
2922 	void *local_mem;
2923 
2924 	hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, 4,
2925 						  dev_to_node(hcd->self.sysdev),
2926 						  dev_name(hcd->self.sysdev));
2927 	if (IS_ERR(hcd->localmem_pool))
2928 		return PTR_ERR(hcd->localmem_pool);
2929 
2930 	local_mem = devm_memremap(hcd->self.sysdev, phys_addr,
2931 				  size, MEMREMAP_WC);
2932 	if (IS_ERR(local_mem))
2933 		return PTR_ERR(local_mem);
2934 
2935 	/*
2936 	 * Here we pass a dma_addr_t but the arg type is a phys_addr_t.
2937 	 * It's not backed by system memory and thus there's no kernel mapping
2938 	 * for it.
2939 	 */
2940 	err = gen_pool_add_virt(hcd->localmem_pool, (unsigned long)local_mem,
2941 				dma, size, dev_to_node(hcd->self.sysdev));
2942 	if (err < 0) {
2943 		dev_err(hcd->self.sysdev, "gen_pool_add_virt failed with %d\n",
2944 			err);
2945 		return err;
2946 	}
2947 
2948 	return 0;
2949 }
2950 EXPORT_SYMBOL_GPL(usb_hcd_setup_local_mem);
2951 
2952 /*-------------------------------------------------------------------------*/
2953 
2954 #if IS_ENABLED(CONFIG_USB_MON)
2955 
2956 const struct usb_mon_operations *mon_ops;
2957 
2958 /*
2959  * The registration is unlocked.
2960  * We do it this way because we do not want to lock in hot paths.
2961  *
2962  * Notice that the code is minimally error-proof. Because usbmon needs
2963  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
2964  */
2965 
2966 int usb_mon_register(const struct usb_mon_operations *ops)
2967 {
2968 
2969 	if (mon_ops)
2970 		return -EBUSY;
2971 
2972 	mon_ops = ops;
2973 	mb();
2974 	return 0;
2975 }
2976 EXPORT_SYMBOL_GPL (usb_mon_register);
2977 
2978 void usb_mon_deregister (void)
2979 {
2980 
2981 	if (mon_ops == NULL) {
2982 		printk(KERN_ERR "USB: monitor was not registered\n");
2983 		return;
2984 	}
2985 	mon_ops = NULL;
2986 	mb();
2987 }
2988 EXPORT_SYMBOL_GPL (usb_mon_deregister);
2989 
2990 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
2991