xref: /openbmc/linux/drivers/usb/core/hcd.c (revision 6c33a6f4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright Linus Torvalds 1999
4  * (C) Copyright Johannes Erdfelt 1999-2001
5  * (C) Copyright Andreas Gal 1999
6  * (C) Copyright Gregory P. Smith 1999
7  * (C) Copyright Deti Fliegl 1999
8  * (C) Copyright Randy Dunlap 2000
9  * (C) Copyright David Brownell 2000-2002
10  */
11 
12 #include <linux/bcd.h>
13 #include <linux/module.h>
14 #include <linux/version.h>
15 #include <linux/kernel.h>
16 #include <linux/sched/task_stack.h>
17 #include <linux/slab.h>
18 #include <linux/completion.h>
19 #include <linux/utsname.h>
20 #include <linux/mm.h>
21 #include <asm/io.h>
22 #include <linux/device.h>
23 #include <linux/dma-mapping.h>
24 #include <linux/mutex.h>
25 #include <asm/irq.h>
26 #include <asm/byteorder.h>
27 #include <asm/unaligned.h>
28 #include <linux/platform_device.h>
29 #include <linux/workqueue.h>
30 #include <linux/pm_runtime.h>
31 #include <linux/types.h>
32 #include <linux/genalloc.h>
33 #include <linux/io.h>
34 
35 #include <linux/phy/phy.h>
36 #include <linux/usb.h>
37 #include <linux/usb/hcd.h>
38 #include <linux/usb/otg.h>
39 
40 #include "usb.h"
41 #include "phy.h"
42 
43 
44 /*-------------------------------------------------------------------------*/
45 
46 /*
47  * USB Host Controller Driver framework
48  *
49  * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
50  * HCD-specific behaviors/bugs.
51  *
52  * This does error checks, tracks devices and urbs, and delegates to a
53  * "hc_driver" only for code (and data) that really needs to know about
54  * hardware differences.  That includes root hub registers, i/o queues,
55  * and so on ... but as little else as possible.
56  *
57  * Shared code includes most of the "root hub" code (these are emulated,
58  * though each HC's hardware works differently) and PCI glue, plus request
59  * tracking overhead.  The HCD code should only block on spinlocks or on
60  * hardware handshaking; blocking on software events (such as other kernel
61  * threads releasing resources, or completing actions) is all generic.
62  *
63  * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
64  * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
65  * only by the hub driver ... and that neither should be seen or used by
66  * usb client device drivers.
67  *
68  * Contributors of ideas or unattributed patches include: David Brownell,
69  * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
70  *
71  * HISTORY:
72  * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
73  *		associated cleanup.  "usb_hcd" still != "usb_bus".
74  * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
75  */
76 
77 /*-------------------------------------------------------------------------*/
78 
79 /* Keep track of which host controller drivers are loaded */
80 unsigned long usb_hcds_loaded;
81 EXPORT_SYMBOL_GPL(usb_hcds_loaded);
82 
83 /* host controllers we manage */
84 DEFINE_IDR (usb_bus_idr);
85 EXPORT_SYMBOL_GPL (usb_bus_idr);
86 
87 /* used when allocating bus numbers */
88 #define USB_MAXBUS		64
89 
90 /* used when updating list of hcds */
91 DEFINE_MUTEX(usb_bus_idr_lock);	/* exported only for usbfs */
92 EXPORT_SYMBOL_GPL (usb_bus_idr_lock);
93 
94 /* used for controlling access to virtual root hubs */
95 static DEFINE_SPINLOCK(hcd_root_hub_lock);
96 
97 /* used when updating an endpoint's URB list */
98 static DEFINE_SPINLOCK(hcd_urb_list_lock);
99 
100 /* used to protect against unlinking URBs after the device is gone */
101 static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
102 
103 /* wait queue for synchronous unlinks */
104 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
105 
106 /*-------------------------------------------------------------------------*/
107 
108 /*
109  * Sharable chunks of root hub code.
110  */
111 
112 /*-------------------------------------------------------------------------*/
113 #define KERNEL_REL	bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff))
114 #define KERNEL_VER	bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff))
115 
116 /* usb 3.1 root hub device descriptor */
117 static const u8 usb31_rh_dev_descriptor[18] = {
118 	0x12,       /*  __u8  bLength; */
119 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
120 	0x10, 0x03, /*  __le16 bcdUSB; v3.1 */
121 
122 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
123 	0x00,	    /*  __u8  bDeviceSubClass; */
124 	0x03,       /*  __u8  bDeviceProtocol; USB 3 hub */
125 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
126 
127 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
128 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
129 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
130 
131 	0x03,       /*  __u8  iManufacturer; */
132 	0x02,       /*  __u8  iProduct; */
133 	0x01,       /*  __u8  iSerialNumber; */
134 	0x01        /*  __u8  bNumConfigurations; */
135 };
136 
137 /* usb 3.0 root hub device descriptor */
138 static const u8 usb3_rh_dev_descriptor[18] = {
139 	0x12,       /*  __u8  bLength; */
140 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
141 	0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
142 
143 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
144 	0x00,	    /*  __u8  bDeviceSubClass; */
145 	0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
146 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
147 
148 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
149 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
150 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
151 
152 	0x03,       /*  __u8  iManufacturer; */
153 	0x02,       /*  __u8  iProduct; */
154 	0x01,       /*  __u8  iSerialNumber; */
155 	0x01        /*  __u8  bNumConfigurations; */
156 };
157 
158 /* usb 2.5 (wireless USB 1.0) root hub device descriptor */
159 static const u8 usb25_rh_dev_descriptor[18] = {
160 	0x12,       /*  __u8  bLength; */
161 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
162 	0x50, 0x02, /*  __le16 bcdUSB; v2.5 */
163 
164 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
165 	0x00,	    /*  __u8  bDeviceSubClass; */
166 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
167 	0xFF,       /*  __u8  bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */
168 
169 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
170 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
171 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
172 
173 	0x03,       /*  __u8  iManufacturer; */
174 	0x02,       /*  __u8  iProduct; */
175 	0x01,       /*  __u8  iSerialNumber; */
176 	0x01        /*  __u8  bNumConfigurations; */
177 };
178 
179 /* usb 2.0 root hub device descriptor */
180 static const u8 usb2_rh_dev_descriptor[18] = {
181 	0x12,       /*  __u8  bLength; */
182 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
183 	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
184 
185 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
186 	0x00,	    /*  __u8  bDeviceSubClass; */
187 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
188 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
189 
190 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
191 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
192 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
193 
194 	0x03,       /*  __u8  iManufacturer; */
195 	0x02,       /*  __u8  iProduct; */
196 	0x01,       /*  __u8  iSerialNumber; */
197 	0x01        /*  __u8  bNumConfigurations; */
198 };
199 
200 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
201 
202 /* usb 1.1 root hub device descriptor */
203 static const u8 usb11_rh_dev_descriptor[18] = {
204 	0x12,       /*  __u8  bLength; */
205 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
206 	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
207 
208 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
209 	0x00,	    /*  __u8  bDeviceSubClass; */
210 	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
211 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
212 
213 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
214 	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
215 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
216 
217 	0x03,       /*  __u8  iManufacturer; */
218 	0x02,       /*  __u8  iProduct; */
219 	0x01,       /*  __u8  iSerialNumber; */
220 	0x01        /*  __u8  bNumConfigurations; */
221 };
222 
223 
224 /*-------------------------------------------------------------------------*/
225 
226 /* Configuration descriptors for our root hubs */
227 
228 static const u8 fs_rh_config_descriptor[] = {
229 
230 	/* one configuration */
231 	0x09,       /*  __u8  bLength; */
232 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
233 	0x19, 0x00, /*  __le16 wTotalLength; */
234 	0x01,       /*  __u8  bNumInterfaces; (1) */
235 	0x01,       /*  __u8  bConfigurationValue; */
236 	0x00,       /*  __u8  iConfiguration; */
237 	0xc0,       /*  __u8  bmAttributes;
238 				 Bit 7: must be set,
239 				     6: Self-powered,
240 				     5: Remote wakeup,
241 				     4..0: resvd */
242 	0x00,       /*  __u8  MaxPower; */
243 
244 	/* USB 1.1:
245 	 * USB 2.0, single TT organization (mandatory):
246 	 *	one interface, protocol 0
247 	 *
248 	 * USB 2.0, multiple TT organization (optional):
249 	 *	two interfaces, protocols 1 (like single TT)
250 	 *	and 2 (multiple TT mode) ... config is
251 	 *	sometimes settable
252 	 *	NOT IMPLEMENTED
253 	 */
254 
255 	/* one interface */
256 	0x09,       /*  __u8  if_bLength; */
257 	USB_DT_INTERFACE,  /* __u8 if_bDescriptorType; Interface */
258 	0x00,       /*  __u8  if_bInterfaceNumber; */
259 	0x00,       /*  __u8  if_bAlternateSetting; */
260 	0x01,       /*  __u8  if_bNumEndpoints; */
261 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
262 	0x00,       /*  __u8  if_bInterfaceSubClass; */
263 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
264 	0x00,       /*  __u8  if_iInterface; */
265 
266 	/* one endpoint (status change endpoint) */
267 	0x07,       /*  __u8  ep_bLength; */
268 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
269 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
270 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
271 	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
272 	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
273 };
274 
275 static const u8 hs_rh_config_descriptor[] = {
276 
277 	/* one configuration */
278 	0x09,       /*  __u8  bLength; */
279 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
280 	0x19, 0x00, /*  __le16 wTotalLength; */
281 	0x01,       /*  __u8  bNumInterfaces; (1) */
282 	0x01,       /*  __u8  bConfigurationValue; */
283 	0x00,       /*  __u8  iConfiguration; */
284 	0xc0,       /*  __u8  bmAttributes;
285 				 Bit 7: must be set,
286 				     6: Self-powered,
287 				     5: Remote wakeup,
288 				     4..0: resvd */
289 	0x00,       /*  __u8  MaxPower; */
290 
291 	/* USB 1.1:
292 	 * USB 2.0, single TT organization (mandatory):
293 	 *	one interface, protocol 0
294 	 *
295 	 * USB 2.0, multiple TT organization (optional):
296 	 *	two interfaces, protocols 1 (like single TT)
297 	 *	and 2 (multiple TT mode) ... config is
298 	 *	sometimes settable
299 	 *	NOT IMPLEMENTED
300 	 */
301 
302 	/* one interface */
303 	0x09,       /*  __u8  if_bLength; */
304 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
305 	0x00,       /*  __u8  if_bInterfaceNumber; */
306 	0x00,       /*  __u8  if_bAlternateSetting; */
307 	0x01,       /*  __u8  if_bNumEndpoints; */
308 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
309 	0x00,       /*  __u8  if_bInterfaceSubClass; */
310 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
311 	0x00,       /*  __u8  if_iInterface; */
312 
313 	/* one endpoint (status change endpoint) */
314 	0x07,       /*  __u8  ep_bLength; */
315 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
316 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
317 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
318 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
319 		     * see hub.c:hub_configure() for details. */
320 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
321 	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
322 };
323 
324 static const u8 ss_rh_config_descriptor[] = {
325 	/* one configuration */
326 	0x09,       /*  __u8  bLength; */
327 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
328 	0x1f, 0x00, /*  __le16 wTotalLength; */
329 	0x01,       /*  __u8  bNumInterfaces; (1) */
330 	0x01,       /*  __u8  bConfigurationValue; */
331 	0x00,       /*  __u8  iConfiguration; */
332 	0xc0,       /*  __u8  bmAttributes;
333 				 Bit 7: must be set,
334 				     6: Self-powered,
335 				     5: Remote wakeup,
336 				     4..0: resvd */
337 	0x00,       /*  __u8  MaxPower; */
338 
339 	/* one interface */
340 	0x09,       /*  __u8  if_bLength; */
341 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
342 	0x00,       /*  __u8  if_bInterfaceNumber; */
343 	0x00,       /*  __u8  if_bAlternateSetting; */
344 	0x01,       /*  __u8  if_bNumEndpoints; */
345 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
346 	0x00,       /*  __u8  if_bInterfaceSubClass; */
347 	0x00,       /*  __u8  if_bInterfaceProtocol; */
348 	0x00,       /*  __u8  if_iInterface; */
349 
350 	/* one endpoint (status change endpoint) */
351 	0x07,       /*  __u8  ep_bLength; */
352 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
353 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
354 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
355 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
356 		     * see hub.c:hub_configure() for details. */
357 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
358 	0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
359 
360 	/* one SuperSpeed endpoint companion descriptor */
361 	0x06,        /* __u8 ss_bLength */
362 	USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */
363 		     /* Companion */
364 	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
365 	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
366 	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
367 };
368 
369 /* authorized_default behaviour:
370  * -1 is authorized for all devices except wireless (old behaviour)
371  * 0 is unauthorized for all devices
372  * 1 is authorized for all devices
373  * 2 is authorized for internal devices
374  */
375 #define USB_AUTHORIZE_WIRED	-1
376 #define USB_AUTHORIZE_NONE	0
377 #define USB_AUTHORIZE_ALL	1
378 #define USB_AUTHORIZE_INTERNAL	2
379 
380 static int authorized_default = USB_AUTHORIZE_WIRED;
381 module_param(authorized_default, int, S_IRUGO|S_IWUSR);
382 MODULE_PARM_DESC(authorized_default,
383 		"Default USB device authorization: 0 is not authorized, 1 is "
384 		"authorized, 2 is authorized for internal devices, -1 is "
385 		"authorized except for wireless USB (default, old behaviour)");
386 /*-------------------------------------------------------------------------*/
387 
388 /**
389  * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
390  * @s: Null-terminated ASCII (actually ISO-8859-1) string
391  * @buf: Buffer for USB string descriptor (header + UTF-16LE)
392  * @len: Length (in bytes; may be odd) of descriptor buffer.
393  *
394  * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
395  * whichever is less.
396  *
397  * Note:
398  * USB String descriptors can contain at most 126 characters; input
399  * strings longer than that are truncated.
400  */
401 static unsigned
402 ascii2desc(char const *s, u8 *buf, unsigned len)
403 {
404 	unsigned n, t = 2 + 2*strlen(s);
405 
406 	if (t > 254)
407 		t = 254;	/* Longest possible UTF string descriptor */
408 	if (len > t)
409 		len = t;
410 
411 	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
412 
413 	n = len;
414 	while (n--) {
415 		*buf++ = t;
416 		if (!n--)
417 			break;
418 		*buf++ = t >> 8;
419 		t = (unsigned char)*s++;
420 	}
421 	return len;
422 }
423 
424 /**
425  * rh_string() - provides string descriptors for root hub
426  * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
427  * @hcd: the host controller for this root hub
428  * @data: buffer for output packet
429  * @len: length of the provided buffer
430  *
431  * Produces either a manufacturer, product or serial number string for the
432  * virtual root hub device.
433  *
434  * Return: The number of bytes filled in: the length of the descriptor or
435  * of the provided buffer, whichever is less.
436  */
437 static unsigned
438 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
439 {
440 	char buf[100];
441 	char const *s;
442 	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
443 
444 	/* language ids */
445 	switch (id) {
446 	case 0:
447 		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
448 		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
449 		if (len > 4)
450 			len = 4;
451 		memcpy(data, langids, len);
452 		return len;
453 	case 1:
454 		/* Serial number */
455 		s = hcd->self.bus_name;
456 		break;
457 	case 2:
458 		/* Product name */
459 		s = hcd->product_desc;
460 		break;
461 	case 3:
462 		/* Manufacturer */
463 		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
464 			init_utsname()->release, hcd->driver->description);
465 		s = buf;
466 		break;
467 	default:
468 		/* Can't happen; caller guarantees it */
469 		return 0;
470 	}
471 
472 	return ascii2desc(s, data, len);
473 }
474 
475 
476 /* Root hub control transfers execute synchronously */
477 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
478 {
479 	struct usb_ctrlrequest *cmd;
480 	u16		typeReq, wValue, wIndex, wLength;
481 	u8		*ubuf = urb->transfer_buffer;
482 	unsigned	len = 0;
483 	int		status;
484 	u8		patch_wakeup = 0;
485 	u8		patch_protocol = 0;
486 	u16		tbuf_size;
487 	u8		*tbuf = NULL;
488 	const u8	*bufp;
489 
490 	might_sleep();
491 
492 	spin_lock_irq(&hcd_root_hub_lock);
493 	status = usb_hcd_link_urb_to_ep(hcd, urb);
494 	spin_unlock_irq(&hcd_root_hub_lock);
495 	if (status)
496 		return status;
497 	urb->hcpriv = hcd;	/* Indicate it's queued */
498 
499 	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
500 	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
501 	wValue   = le16_to_cpu (cmd->wValue);
502 	wIndex   = le16_to_cpu (cmd->wIndex);
503 	wLength  = le16_to_cpu (cmd->wLength);
504 
505 	if (wLength > urb->transfer_buffer_length)
506 		goto error;
507 
508 	/*
509 	 * tbuf should be at least as big as the
510 	 * USB hub descriptor.
511 	 */
512 	tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
513 	tbuf = kzalloc(tbuf_size, GFP_KERNEL);
514 	if (!tbuf) {
515 		status = -ENOMEM;
516 		goto err_alloc;
517 	}
518 
519 	bufp = tbuf;
520 
521 
522 	urb->actual_length = 0;
523 	switch (typeReq) {
524 
525 	/* DEVICE REQUESTS */
526 
527 	/* The root hub's remote wakeup enable bit is implemented using
528 	 * driver model wakeup flags.  If this system supports wakeup
529 	 * through USB, userspace may change the default "allow wakeup"
530 	 * policy through sysfs or these calls.
531 	 *
532 	 * Most root hubs support wakeup from downstream devices, for
533 	 * runtime power management (disabling USB clocks and reducing
534 	 * VBUS power usage).  However, not all of them do so; silicon,
535 	 * board, and BIOS bugs here are not uncommon, so these can't
536 	 * be treated quite like external hubs.
537 	 *
538 	 * Likewise, not all root hubs will pass wakeup events upstream,
539 	 * to wake up the whole system.  So don't assume root hub and
540 	 * controller capabilities are identical.
541 	 */
542 
543 	case DeviceRequest | USB_REQ_GET_STATUS:
544 		tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
545 					<< USB_DEVICE_REMOTE_WAKEUP)
546 				| (1 << USB_DEVICE_SELF_POWERED);
547 		tbuf[1] = 0;
548 		len = 2;
549 		break;
550 	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
551 		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
552 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
553 		else
554 			goto error;
555 		break;
556 	case DeviceOutRequest | USB_REQ_SET_FEATURE:
557 		if (device_can_wakeup(&hcd->self.root_hub->dev)
558 				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
559 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
560 		else
561 			goto error;
562 		break;
563 	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
564 		tbuf[0] = 1;
565 		len = 1;
566 			/* FALLTHROUGH */
567 	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
568 		break;
569 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
570 		switch (wValue & 0xff00) {
571 		case USB_DT_DEVICE << 8:
572 			switch (hcd->speed) {
573 			case HCD_USB32:
574 			case HCD_USB31:
575 				bufp = usb31_rh_dev_descriptor;
576 				break;
577 			case HCD_USB3:
578 				bufp = usb3_rh_dev_descriptor;
579 				break;
580 			case HCD_USB25:
581 				bufp = usb25_rh_dev_descriptor;
582 				break;
583 			case HCD_USB2:
584 				bufp = usb2_rh_dev_descriptor;
585 				break;
586 			case HCD_USB11:
587 				bufp = usb11_rh_dev_descriptor;
588 				break;
589 			default:
590 				goto error;
591 			}
592 			len = 18;
593 			if (hcd->has_tt)
594 				patch_protocol = 1;
595 			break;
596 		case USB_DT_CONFIG << 8:
597 			switch (hcd->speed) {
598 			case HCD_USB32:
599 			case HCD_USB31:
600 			case HCD_USB3:
601 				bufp = ss_rh_config_descriptor;
602 				len = sizeof ss_rh_config_descriptor;
603 				break;
604 			case HCD_USB25:
605 			case HCD_USB2:
606 				bufp = hs_rh_config_descriptor;
607 				len = sizeof hs_rh_config_descriptor;
608 				break;
609 			case HCD_USB11:
610 				bufp = fs_rh_config_descriptor;
611 				len = sizeof fs_rh_config_descriptor;
612 				break;
613 			default:
614 				goto error;
615 			}
616 			if (device_can_wakeup(&hcd->self.root_hub->dev))
617 				patch_wakeup = 1;
618 			break;
619 		case USB_DT_STRING << 8:
620 			if ((wValue & 0xff) < 4)
621 				urb->actual_length = rh_string(wValue & 0xff,
622 						hcd, ubuf, wLength);
623 			else /* unsupported IDs --> "protocol stall" */
624 				goto error;
625 			break;
626 		case USB_DT_BOS << 8:
627 			goto nongeneric;
628 		default:
629 			goto error;
630 		}
631 		break;
632 	case DeviceRequest | USB_REQ_GET_INTERFACE:
633 		tbuf[0] = 0;
634 		len = 1;
635 			/* FALLTHROUGH */
636 	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
637 		break;
638 	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
639 		/* wValue == urb->dev->devaddr */
640 		dev_dbg (hcd->self.controller, "root hub device address %d\n",
641 			wValue);
642 		break;
643 
644 	/* INTERFACE REQUESTS (no defined feature/status flags) */
645 
646 	/* ENDPOINT REQUESTS */
647 
648 	case EndpointRequest | USB_REQ_GET_STATUS:
649 		/* ENDPOINT_HALT flag */
650 		tbuf[0] = 0;
651 		tbuf[1] = 0;
652 		len = 2;
653 			/* FALLTHROUGH */
654 	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
655 	case EndpointOutRequest | USB_REQ_SET_FEATURE:
656 		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
657 		break;
658 
659 	/* CLASS REQUESTS (and errors) */
660 
661 	default:
662 nongeneric:
663 		/* non-generic request */
664 		switch (typeReq) {
665 		case GetHubStatus:
666 			len = 4;
667 			break;
668 		case GetPortStatus:
669 			if (wValue == HUB_PORT_STATUS)
670 				len = 4;
671 			else
672 				/* other port status types return 8 bytes */
673 				len = 8;
674 			break;
675 		case GetHubDescriptor:
676 			len = sizeof (struct usb_hub_descriptor);
677 			break;
678 		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
679 			/* len is returned by hub_control */
680 			break;
681 		}
682 		status = hcd->driver->hub_control (hcd,
683 			typeReq, wValue, wIndex,
684 			tbuf, wLength);
685 
686 		if (typeReq == GetHubDescriptor)
687 			usb_hub_adjust_deviceremovable(hcd->self.root_hub,
688 				(struct usb_hub_descriptor *)tbuf);
689 		break;
690 error:
691 		/* "protocol stall" on error */
692 		status = -EPIPE;
693 	}
694 
695 	if (status < 0) {
696 		len = 0;
697 		if (status != -EPIPE) {
698 			dev_dbg (hcd->self.controller,
699 				"CTRL: TypeReq=0x%x val=0x%x "
700 				"idx=0x%x len=%d ==> %d\n",
701 				typeReq, wValue, wIndex,
702 				wLength, status);
703 		}
704 	} else if (status > 0) {
705 		/* hub_control may return the length of data copied. */
706 		len = status;
707 		status = 0;
708 	}
709 	if (len) {
710 		if (urb->transfer_buffer_length < len)
711 			len = urb->transfer_buffer_length;
712 		urb->actual_length = len;
713 		/* always USB_DIR_IN, toward host */
714 		memcpy (ubuf, bufp, len);
715 
716 		/* report whether RH hardware supports remote wakeup */
717 		if (patch_wakeup &&
718 				len > offsetof (struct usb_config_descriptor,
719 						bmAttributes))
720 			((struct usb_config_descriptor *)ubuf)->bmAttributes
721 				|= USB_CONFIG_ATT_WAKEUP;
722 
723 		/* report whether RH hardware has an integrated TT */
724 		if (patch_protocol &&
725 				len > offsetof(struct usb_device_descriptor,
726 						bDeviceProtocol))
727 			((struct usb_device_descriptor *) ubuf)->
728 				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
729 	}
730 
731 	kfree(tbuf);
732  err_alloc:
733 
734 	/* any errors get returned through the urb completion */
735 	spin_lock_irq(&hcd_root_hub_lock);
736 	usb_hcd_unlink_urb_from_ep(hcd, urb);
737 	usb_hcd_giveback_urb(hcd, urb, status);
738 	spin_unlock_irq(&hcd_root_hub_lock);
739 	return 0;
740 }
741 
742 /*-------------------------------------------------------------------------*/
743 
744 /*
745  * Root Hub interrupt transfers are polled using a timer if the
746  * driver requests it; otherwise the driver is responsible for
747  * calling usb_hcd_poll_rh_status() when an event occurs.
748  *
749  * Completions are called in_interrupt(), but they may or may not
750  * be in_irq().
751  */
752 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
753 {
754 	struct urb	*urb;
755 	int		length;
756 	unsigned long	flags;
757 	char		buffer[6];	/* Any root hubs with > 31 ports? */
758 
759 	if (unlikely(!hcd->rh_pollable))
760 		return;
761 	if (!hcd->uses_new_polling && !hcd->status_urb)
762 		return;
763 
764 	length = hcd->driver->hub_status_data(hcd, buffer);
765 	if (length > 0) {
766 
767 		/* try to complete the status urb */
768 		spin_lock_irqsave(&hcd_root_hub_lock, flags);
769 		urb = hcd->status_urb;
770 		if (urb) {
771 			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
772 			hcd->status_urb = NULL;
773 			urb->actual_length = length;
774 			memcpy(urb->transfer_buffer, buffer, length);
775 
776 			usb_hcd_unlink_urb_from_ep(hcd, urb);
777 			usb_hcd_giveback_urb(hcd, urb, 0);
778 		} else {
779 			length = 0;
780 			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
781 		}
782 		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
783 	}
784 
785 	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
786 	 * exceed that limit if HZ is 100. The math is more clunky than
787 	 * maybe expected, this is to make sure that all timers for USB devices
788 	 * fire at the same time to give the CPU a break in between */
789 	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
790 			(length == 0 && hcd->status_urb != NULL))
791 		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
792 }
793 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
794 
795 /* timer callback */
796 static void rh_timer_func (struct timer_list *t)
797 {
798 	struct usb_hcd *_hcd = from_timer(_hcd, t, rh_timer);
799 
800 	usb_hcd_poll_rh_status(_hcd);
801 }
802 
803 /*-------------------------------------------------------------------------*/
804 
805 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
806 {
807 	int		retval;
808 	unsigned long	flags;
809 	unsigned	len = 1 + (urb->dev->maxchild / 8);
810 
811 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
812 	if (hcd->status_urb || urb->transfer_buffer_length < len) {
813 		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
814 		retval = -EINVAL;
815 		goto done;
816 	}
817 
818 	retval = usb_hcd_link_urb_to_ep(hcd, urb);
819 	if (retval)
820 		goto done;
821 
822 	hcd->status_urb = urb;
823 	urb->hcpriv = hcd;	/* indicate it's queued */
824 	if (!hcd->uses_new_polling)
825 		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
826 
827 	/* If a status change has already occurred, report it ASAP */
828 	else if (HCD_POLL_PENDING(hcd))
829 		mod_timer(&hcd->rh_timer, jiffies);
830 	retval = 0;
831  done:
832 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
833 	return retval;
834 }
835 
836 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
837 {
838 	if (usb_endpoint_xfer_int(&urb->ep->desc))
839 		return rh_queue_status (hcd, urb);
840 	if (usb_endpoint_xfer_control(&urb->ep->desc))
841 		return rh_call_control (hcd, urb);
842 	return -EINVAL;
843 }
844 
845 /*-------------------------------------------------------------------------*/
846 
847 /* Unlinks of root-hub control URBs are legal, but they don't do anything
848  * since these URBs always execute synchronously.
849  */
850 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
851 {
852 	unsigned long	flags;
853 	int		rc;
854 
855 	spin_lock_irqsave(&hcd_root_hub_lock, flags);
856 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
857 	if (rc)
858 		goto done;
859 
860 	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
861 		;	/* Do nothing */
862 
863 	} else {				/* Status URB */
864 		if (!hcd->uses_new_polling)
865 			del_timer (&hcd->rh_timer);
866 		if (urb == hcd->status_urb) {
867 			hcd->status_urb = NULL;
868 			usb_hcd_unlink_urb_from_ep(hcd, urb);
869 			usb_hcd_giveback_urb(hcd, urb, status);
870 		}
871 	}
872  done:
873 	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
874 	return rc;
875 }
876 
877 
878 /*-------------------------------------------------------------------------*/
879 
880 /**
881  * usb_bus_init - shared initialization code
882  * @bus: the bus structure being initialized
883  *
884  * This code is used to initialize a usb_bus structure, memory for which is
885  * separately managed.
886  */
887 static void usb_bus_init (struct usb_bus *bus)
888 {
889 	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
890 
891 	bus->devnum_next = 1;
892 
893 	bus->root_hub = NULL;
894 	bus->busnum = -1;
895 	bus->bandwidth_allocated = 0;
896 	bus->bandwidth_int_reqs  = 0;
897 	bus->bandwidth_isoc_reqs = 0;
898 	mutex_init(&bus->devnum_next_mutex);
899 }
900 
901 /*-------------------------------------------------------------------------*/
902 
903 /**
904  * usb_register_bus - registers the USB host controller with the usb core
905  * @bus: pointer to the bus to register
906  * Context: !in_interrupt()
907  *
908  * Assigns a bus number, and links the controller into usbcore data
909  * structures so that it can be seen by scanning the bus list.
910  *
911  * Return: 0 if successful. A negative error code otherwise.
912  */
913 static int usb_register_bus(struct usb_bus *bus)
914 {
915 	int result = -E2BIG;
916 	int busnum;
917 
918 	mutex_lock(&usb_bus_idr_lock);
919 	busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL);
920 	if (busnum < 0) {
921 		pr_err("%s: failed to get bus number\n", usbcore_name);
922 		goto error_find_busnum;
923 	}
924 	bus->busnum = busnum;
925 	mutex_unlock(&usb_bus_idr_lock);
926 
927 	usb_notify_add_bus(bus);
928 
929 	dev_info (bus->controller, "new USB bus registered, assigned bus "
930 		  "number %d\n", bus->busnum);
931 	return 0;
932 
933 error_find_busnum:
934 	mutex_unlock(&usb_bus_idr_lock);
935 	return result;
936 }
937 
938 /**
939  * usb_deregister_bus - deregisters the USB host controller
940  * @bus: pointer to the bus to deregister
941  * Context: !in_interrupt()
942  *
943  * Recycles the bus number, and unlinks the controller from usbcore data
944  * structures so that it won't be seen by scanning the bus list.
945  */
946 static void usb_deregister_bus (struct usb_bus *bus)
947 {
948 	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
949 
950 	/*
951 	 * NOTE: make sure that all the devices are removed by the
952 	 * controller code, as well as having it call this when cleaning
953 	 * itself up
954 	 */
955 	mutex_lock(&usb_bus_idr_lock);
956 	idr_remove(&usb_bus_idr, bus->busnum);
957 	mutex_unlock(&usb_bus_idr_lock);
958 
959 	usb_notify_remove_bus(bus);
960 }
961 
962 /**
963  * register_root_hub - called by usb_add_hcd() to register a root hub
964  * @hcd: host controller for this root hub
965  *
966  * This function registers the root hub with the USB subsystem.  It sets up
967  * the device properly in the device tree and then calls usb_new_device()
968  * to register the usb device.  It also assigns the root hub's USB address
969  * (always 1).
970  *
971  * Return: 0 if successful. A negative error code otherwise.
972  */
973 static int register_root_hub(struct usb_hcd *hcd)
974 {
975 	struct device *parent_dev = hcd->self.controller;
976 	struct usb_device *usb_dev = hcd->self.root_hub;
977 	const int devnum = 1;
978 	int retval;
979 
980 	usb_dev->devnum = devnum;
981 	usb_dev->bus->devnum_next = devnum + 1;
982 	set_bit (devnum, usb_dev->bus->devmap.devicemap);
983 	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
984 
985 	mutex_lock(&usb_bus_idr_lock);
986 
987 	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
988 	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
989 	if (retval != sizeof usb_dev->descriptor) {
990 		mutex_unlock(&usb_bus_idr_lock);
991 		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
992 				dev_name(&usb_dev->dev), retval);
993 		return (retval < 0) ? retval : -EMSGSIZE;
994 	}
995 
996 	if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
997 		retval = usb_get_bos_descriptor(usb_dev);
998 		if (!retval) {
999 			usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
1000 		} else if (usb_dev->speed >= USB_SPEED_SUPER) {
1001 			mutex_unlock(&usb_bus_idr_lock);
1002 			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1003 					dev_name(&usb_dev->dev), retval);
1004 			return retval;
1005 		}
1006 	}
1007 
1008 	retval = usb_new_device (usb_dev);
1009 	if (retval) {
1010 		dev_err (parent_dev, "can't register root hub for %s, %d\n",
1011 				dev_name(&usb_dev->dev), retval);
1012 	} else {
1013 		spin_lock_irq (&hcd_root_hub_lock);
1014 		hcd->rh_registered = 1;
1015 		spin_unlock_irq (&hcd_root_hub_lock);
1016 
1017 		/* Did the HC die before the root hub was registered? */
1018 		if (HCD_DEAD(hcd))
1019 			usb_hc_died (hcd);	/* This time clean up */
1020 	}
1021 	mutex_unlock(&usb_bus_idr_lock);
1022 
1023 	return retval;
1024 }
1025 
1026 /*
1027  * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1028  * @bus: the bus which the root hub belongs to
1029  * @portnum: the port which is being resumed
1030  *
1031  * HCDs should call this function when they know that a resume signal is
1032  * being sent to a root-hub port.  The root hub will be prevented from
1033  * going into autosuspend until usb_hcd_end_port_resume() is called.
1034  *
1035  * The bus's private lock must be held by the caller.
1036  */
1037 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1038 {
1039 	unsigned bit = 1 << portnum;
1040 
1041 	if (!(bus->resuming_ports & bit)) {
1042 		bus->resuming_ports |= bit;
1043 		pm_runtime_get_noresume(&bus->root_hub->dev);
1044 	}
1045 }
1046 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1047 
1048 /*
1049  * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1050  * @bus: the bus which the root hub belongs to
1051  * @portnum: the port which is being resumed
1052  *
1053  * HCDs should call this function when they know that a resume signal has
1054  * stopped being sent to a root-hub port.  The root hub will be allowed to
1055  * autosuspend again.
1056  *
1057  * The bus's private lock must be held by the caller.
1058  */
1059 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1060 {
1061 	unsigned bit = 1 << portnum;
1062 
1063 	if (bus->resuming_ports & bit) {
1064 		bus->resuming_ports &= ~bit;
1065 		pm_runtime_put_noidle(&bus->root_hub->dev);
1066 	}
1067 }
1068 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1069 
1070 /*-------------------------------------------------------------------------*/
1071 
1072 /**
1073  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1074  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1075  * @is_input: true iff the transaction sends data to the host
1076  * @isoc: true for isochronous transactions, false for interrupt ones
1077  * @bytecount: how many bytes in the transaction.
1078  *
1079  * Return: Approximate bus time in nanoseconds for a periodic transaction.
1080  *
1081  * Note:
1082  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1083  * scheduled in software, this function is only used for such scheduling.
1084  */
1085 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1086 {
1087 	unsigned long	tmp;
1088 
1089 	switch (speed) {
1090 	case USB_SPEED_LOW: 	/* INTR only */
1091 		if (is_input) {
1092 			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1093 			return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1094 		} else {
1095 			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1096 			return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1097 		}
1098 	case USB_SPEED_FULL:	/* ISOC or INTR */
1099 		if (isoc) {
1100 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1101 			return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1102 		} else {
1103 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1104 			return 9107L + BW_HOST_DELAY + tmp;
1105 		}
1106 	case USB_SPEED_HIGH:	/* ISOC or INTR */
1107 		/* FIXME adjust for input vs output */
1108 		if (isoc)
1109 			tmp = HS_NSECS_ISO (bytecount);
1110 		else
1111 			tmp = HS_NSECS (bytecount);
1112 		return tmp;
1113 	default:
1114 		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1115 		return -1;
1116 	}
1117 }
1118 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1119 
1120 
1121 /*-------------------------------------------------------------------------*/
1122 
1123 /*
1124  * Generic HC operations.
1125  */
1126 
1127 /*-------------------------------------------------------------------------*/
1128 
1129 /**
1130  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1131  * @hcd: host controller to which @urb was submitted
1132  * @urb: URB being submitted
1133  *
1134  * Host controller drivers should call this routine in their enqueue()
1135  * method.  The HCD's private spinlock must be held and interrupts must
1136  * be disabled.  The actions carried out here are required for URB
1137  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1138  *
1139  * Return: 0 for no error, otherwise a negative error code (in which case
1140  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1141  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1142  * the private spinlock and returning.
1143  */
1144 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1145 {
1146 	int		rc = 0;
1147 
1148 	spin_lock(&hcd_urb_list_lock);
1149 
1150 	/* Check that the URB isn't being killed */
1151 	if (unlikely(atomic_read(&urb->reject))) {
1152 		rc = -EPERM;
1153 		goto done;
1154 	}
1155 
1156 	if (unlikely(!urb->ep->enabled)) {
1157 		rc = -ENOENT;
1158 		goto done;
1159 	}
1160 
1161 	if (unlikely(!urb->dev->can_submit)) {
1162 		rc = -EHOSTUNREACH;
1163 		goto done;
1164 	}
1165 
1166 	/*
1167 	 * Check the host controller's state and add the URB to the
1168 	 * endpoint's queue.
1169 	 */
1170 	if (HCD_RH_RUNNING(hcd)) {
1171 		urb->unlinked = 0;
1172 		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1173 	} else {
1174 		rc = -ESHUTDOWN;
1175 		goto done;
1176 	}
1177  done:
1178 	spin_unlock(&hcd_urb_list_lock);
1179 	return rc;
1180 }
1181 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1182 
1183 /**
1184  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1185  * @hcd: host controller to which @urb was submitted
1186  * @urb: URB being checked for unlinkability
1187  * @status: error code to store in @urb if the unlink succeeds
1188  *
1189  * Host controller drivers should call this routine in their dequeue()
1190  * method.  The HCD's private spinlock must be held and interrupts must
1191  * be disabled.  The actions carried out here are required for making
1192  * sure than an unlink is valid.
1193  *
1194  * Return: 0 for no error, otherwise a negative error code (in which case
1195  * the dequeue() method must fail).  The possible error codes are:
1196  *
1197  *	-EIDRM: @urb was not submitted or has already completed.
1198  *		The completion function may not have been called yet.
1199  *
1200  *	-EBUSY: @urb has already been unlinked.
1201  */
1202 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1203 		int status)
1204 {
1205 	struct list_head	*tmp;
1206 
1207 	/* insist the urb is still queued */
1208 	list_for_each(tmp, &urb->ep->urb_list) {
1209 		if (tmp == &urb->urb_list)
1210 			break;
1211 	}
1212 	if (tmp != &urb->urb_list)
1213 		return -EIDRM;
1214 
1215 	/* Any status except -EINPROGRESS means something already started to
1216 	 * unlink this URB from the hardware.  So there's no more work to do.
1217 	 */
1218 	if (urb->unlinked)
1219 		return -EBUSY;
1220 	urb->unlinked = status;
1221 	return 0;
1222 }
1223 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1224 
1225 /**
1226  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1227  * @hcd: host controller to which @urb was submitted
1228  * @urb: URB being unlinked
1229  *
1230  * Host controller drivers should call this routine before calling
1231  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1232  * interrupts must be disabled.  The actions carried out here are required
1233  * for URB completion.
1234  */
1235 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1236 {
1237 	/* clear all state linking urb to this dev (and hcd) */
1238 	spin_lock(&hcd_urb_list_lock);
1239 	list_del_init(&urb->urb_list);
1240 	spin_unlock(&hcd_urb_list_lock);
1241 }
1242 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1243 
1244 /*
1245  * Some usb host controllers can only perform dma using a small SRAM area.
1246  * The usb core itself is however optimized for host controllers that can dma
1247  * using regular system memory - like pci devices doing bus mastering.
1248  *
1249  * To support host controllers with limited dma capabilities we provide dma
1250  * bounce buffers. This feature can be enabled by initializing
1251  * hcd->localmem_pool using usb_hcd_setup_local_mem().
1252  *
1253  * The initialized hcd->localmem_pool then tells the usb code to allocate all
1254  * data for dma using the genalloc API.
1255  *
1256  * So, to summarize...
1257  *
1258  * - We need "local" memory, canonical example being
1259  *   a small SRAM on a discrete controller being the
1260  *   only memory that the controller can read ...
1261  *   (a) "normal" kernel memory is no good, and
1262  *   (b) there's not enough to share
1263  *
1264  * - So we use that, even though the primary requirement
1265  *   is that the memory be "local" (hence addressable
1266  *   by that device), not "coherent".
1267  *
1268  */
1269 
1270 static int hcd_alloc_coherent(struct usb_bus *bus,
1271 			      gfp_t mem_flags, dma_addr_t *dma_handle,
1272 			      void **vaddr_handle, size_t size,
1273 			      enum dma_data_direction dir)
1274 {
1275 	unsigned char *vaddr;
1276 
1277 	if (*vaddr_handle == NULL) {
1278 		WARN_ON_ONCE(1);
1279 		return -EFAULT;
1280 	}
1281 
1282 	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1283 				 mem_flags, dma_handle);
1284 	if (!vaddr)
1285 		return -ENOMEM;
1286 
1287 	/*
1288 	 * Store the virtual address of the buffer at the end
1289 	 * of the allocated dma buffer. The size of the buffer
1290 	 * may be uneven so use unaligned functions instead
1291 	 * of just rounding up. It makes sense to optimize for
1292 	 * memory footprint over access speed since the amount
1293 	 * of memory available for dma may be limited.
1294 	 */
1295 	put_unaligned((unsigned long)*vaddr_handle,
1296 		      (unsigned long *)(vaddr + size));
1297 
1298 	if (dir == DMA_TO_DEVICE)
1299 		memcpy(vaddr, *vaddr_handle, size);
1300 
1301 	*vaddr_handle = vaddr;
1302 	return 0;
1303 }
1304 
1305 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1306 			      void **vaddr_handle, size_t size,
1307 			      enum dma_data_direction dir)
1308 {
1309 	unsigned char *vaddr = *vaddr_handle;
1310 
1311 	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1312 
1313 	if (dir == DMA_FROM_DEVICE)
1314 		memcpy(vaddr, *vaddr_handle, size);
1315 
1316 	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1317 
1318 	*vaddr_handle = vaddr;
1319 	*dma_handle = 0;
1320 }
1321 
1322 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1323 {
1324 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1325 	    (urb->transfer_flags & URB_SETUP_MAP_SINGLE))
1326 		dma_unmap_single(hcd->self.sysdev,
1327 				urb->setup_dma,
1328 				sizeof(struct usb_ctrlrequest),
1329 				DMA_TO_DEVICE);
1330 	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1331 		hcd_free_coherent(urb->dev->bus,
1332 				&urb->setup_dma,
1333 				(void **) &urb->setup_packet,
1334 				sizeof(struct usb_ctrlrequest),
1335 				DMA_TO_DEVICE);
1336 
1337 	/* Make it safe to call this routine more than once */
1338 	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1339 }
1340 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1341 
1342 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1343 {
1344 	if (hcd->driver->unmap_urb_for_dma)
1345 		hcd->driver->unmap_urb_for_dma(hcd, urb);
1346 	else
1347 		usb_hcd_unmap_urb_for_dma(hcd, urb);
1348 }
1349 
1350 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1351 {
1352 	enum dma_data_direction dir;
1353 
1354 	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1355 
1356 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1357 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1358 	    (urb->transfer_flags & URB_DMA_MAP_SG))
1359 		dma_unmap_sg(hcd->self.sysdev,
1360 				urb->sg,
1361 				urb->num_sgs,
1362 				dir);
1363 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1364 		 (urb->transfer_flags & URB_DMA_MAP_PAGE))
1365 		dma_unmap_page(hcd->self.sysdev,
1366 				urb->transfer_dma,
1367 				urb->transfer_buffer_length,
1368 				dir);
1369 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1370 		 (urb->transfer_flags & URB_DMA_MAP_SINGLE))
1371 		dma_unmap_single(hcd->self.sysdev,
1372 				urb->transfer_dma,
1373 				urb->transfer_buffer_length,
1374 				dir);
1375 	else if (urb->transfer_flags & URB_MAP_LOCAL)
1376 		hcd_free_coherent(urb->dev->bus,
1377 				&urb->transfer_dma,
1378 				&urb->transfer_buffer,
1379 				urb->transfer_buffer_length,
1380 				dir);
1381 
1382 	/* Make it safe to call this routine more than once */
1383 	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1384 			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1385 }
1386 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1387 
1388 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1389 			   gfp_t mem_flags)
1390 {
1391 	if (hcd->driver->map_urb_for_dma)
1392 		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1393 	else
1394 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1395 }
1396 
1397 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1398 			    gfp_t mem_flags)
1399 {
1400 	enum dma_data_direction dir;
1401 	int ret = 0;
1402 
1403 	/* Map the URB's buffers for DMA access.
1404 	 * Lower level HCD code should use *_dma exclusively,
1405 	 * unless it uses pio or talks to another transport,
1406 	 * or uses the provided scatter gather list for bulk.
1407 	 */
1408 
1409 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1410 		if (hcd->self.uses_pio_for_control)
1411 			return ret;
1412 		if (hcd->localmem_pool) {
1413 			ret = hcd_alloc_coherent(
1414 					urb->dev->bus, mem_flags,
1415 					&urb->setup_dma,
1416 					(void **)&urb->setup_packet,
1417 					sizeof(struct usb_ctrlrequest),
1418 					DMA_TO_DEVICE);
1419 			if (ret)
1420 				return ret;
1421 			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1422 		} else if (hcd_uses_dma(hcd)) {
1423 			if (object_is_on_stack(urb->setup_packet)) {
1424 				WARN_ONCE(1, "setup packet is on stack\n");
1425 				return -EAGAIN;
1426 			}
1427 
1428 			urb->setup_dma = dma_map_single(
1429 					hcd->self.sysdev,
1430 					urb->setup_packet,
1431 					sizeof(struct usb_ctrlrequest),
1432 					DMA_TO_DEVICE);
1433 			if (dma_mapping_error(hcd->self.sysdev,
1434 						urb->setup_dma))
1435 				return -EAGAIN;
1436 			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1437 		}
1438 	}
1439 
1440 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1441 	if (urb->transfer_buffer_length != 0
1442 	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1443 		if (hcd->localmem_pool) {
1444 			ret = hcd_alloc_coherent(
1445 					urb->dev->bus, mem_flags,
1446 					&urb->transfer_dma,
1447 					&urb->transfer_buffer,
1448 					urb->transfer_buffer_length,
1449 					dir);
1450 			if (ret == 0)
1451 				urb->transfer_flags |= URB_MAP_LOCAL;
1452 		} else if (hcd_uses_dma(hcd)) {
1453 			if (urb->num_sgs) {
1454 				int n;
1455 
1456 				/* We don't support sg for isoc transfers ! */
1457 				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1458 					WARN_ON(1);
1459 					return -EINVAL;
1460 				}
1461 
1462 				n = dma_map_sg(
1463 						hcd->self.sysdev,
1464 						urb->sg,
1465 						urb->num_sgs,
1466 						dir);
1467 				if (n <= 0)
1468 					ret = -EAGAIN;
1469 				else
1470 					urb->transfer_flags |= URB_DMA_MAP_SG;
1471 				urb->num_mapped_sgs = n;
1472 				if (n != urb->num_sgs)
1473 					urb->transfer_flags |=
1474 							URB_DMA_SG_COMBINED;
1475 			} else if (urb->sg) {
1476 				struct scatterlist *sg = urb->sg;
1477 				urb->transfer_dma = dma_map_page(
1478 						hcd->self.sysdev,
1479 						sg_page(sg),
1480 						sg->offset,
1481 						urb->transfer_buffer_length,
1482 						dir);
1483 				if (dma_mapping_error(hcd->self.sysdev,
1484 						urb->transfer_dma))
1485 					ret = -EAGAIN;
1486 				else
1487 					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1488 			} else if (object_is_on_stack(urb->transfer_buffer)) {
1489 				WARN_ONCE(1, "transfer buffer is on stack\n");
1490 				ret = -EAGAIN;
1491 			} else {
1492 				urb->transfer_dma = dma_map_single(
1493 						hcd->self.sysdev,
1494 						urb->transfer_buffer,
1495 						urb->transfer_buffer_length,
1496 						dir);
1497 				if (dma_mapping_error(hcd->self.sysdev,
1498 						urb->transfer_dma))
1499 					ret = -EAGAIN;
1500 				else
1501 					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1502 			}
1503 		}
1504 		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1505 				URB_SETUP_MAP_LOCAL)))
1506 			usb_hcd_unmap_urb_for_dma(hcd, urb);
1507 	}
1508 	return ret;
1509 }
1510 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1511 
1512 /*-------------------------------------------------------------------------*/
1513 
1514 /* may be called in any context with a valid urb->dev usecount
1515  * caller surrenders "ownership" of urb
1516  * expects usb_submit_urb() to have sanity checked and conditioned all
1517  * inputs in the urb
1518  */
1519 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1520 {
1521 	int			status;
1522 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1523 
1524 	/* increment urb's reference count as part of giving it to the HCD
1525 	 * (which will control it).  HCD guarantees that it either returns
1526 	 * an error or calls giveback(), but not both.
1527 	 */
1528 	usb_get_urb(urb);
1529 	atomic_inc(&urb->use_count);
1530 	atomic_inc(&urb->dev->urbnum);
1531 	usbmon_urb_submit(&hcd->self, urb);
1532 
1533 	/* NOTE requirements on root-hub callers (usbfs and the hub
1534 	 * driver, for now):  URBs' urb->transfer_buffer must be
1535 	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1536 	 * they could clobber root hub response data.  Also, control
1537 	 * URBs must be submitted in process context with interrupts
1538 	 * enabled.
1539 	 */
1540 
1541 	if (is_root_hub(urb->dev)) {
1542 		status = rh_urb_enqueue(hcd, urb);
1543 	} else {
1544 		status = map_urb_for_dma(hcd, urb, mem_flags);
1545 		if (likely(status == 0)) {
1546 			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1547 			if (unlikely(status))
1548 				unmap_urb_for_dma(hcd, urb);
1549 		}
1550 	}
1551 
1552 	if (unlikely(status)) {
1553 		usbmon_urb_submit_error(&hcd->self, urb, status);
1554 		urb->hcpriv = NULL;
1555 		INIT_LIST_HEAD(&urb->urb_list);
1556 		atomic_dec(&urb->use_count);
1557 		atomic_dec(&urb->dev->urbnum);
1558 		if (atomic_read(&urb->reject))
1559 			wake_up(&usb_kill_urb_queue);
1560 		usb_put_urb(urb);
1561 	}
1562 	return status;
1563 }
1564 
1565 /*-------------------------------------------------------------------------*/
1566 
1567 /* this makes the hcd giveback() the urb more quickly, by kicking it
1568  * off hardware queues (which may take a while) and returning it as
1569  * soon as practical.  we've already set up the urb's return status,
1570  * but we can't know if the callback completed already.
1571  */
1572 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1573 {
1574 	int		value;
1575 
1576 	if (is_root_hub(urb->dev))
1577 		value = usb_rh_urb_dequeue(hcd, urb, status);
1578 	else {
1579 
1580 		/* The only reason an HCD might fail this call is if
1581 		 * it has not yet fully queued the urb to begin with.
1582 		 * Such failures should be harmless. */
1583 		value = hcd->driver->urb_dequeue(hcd, urb, status);
1584 	}
1585 	return value;
1586 }
1587 
1588 /*
1589  * called in any context
1590  *
1591  * caller guarantees urb won't be recycled till both unlink()
1592  * and the urb's completion function return
1593  */
1594 int usb_hcd_unlink_urb (struct urb *urb, int status)
1595 {
1596 	struct usb_hcd		*hcd;
1597 	struct usb_device	*udev = urb->dev;
1598 	int			retval = -EIDRM;
1599 	unsigned long		flags;
1600 
1601 	/* Prevent the device and bus from going away while
1602 	 * the unlink is carried out.  If they are already gone
1603 	 * then urb->use_count must be 0, since disconnected
1604 	 * devices can't have any active URBs.
1605 	 */
1606 	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1607 	if (atomic_read(&urb->use_count) > 0) {
1608 		retval = 0;
1609 		usb_get_dev(udev);
1610 	}
1611 	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1612 	if (retval == 0) {
1613 		hcd = bus_to_hcd(urb->dev->bus);
1614 		retval = unlink1(hcd, urb, status);
1615 		if (retval == 0)
1616 			retval = -EINPROGRESS;
1617 		else if (retval != -EIDRM && retval != -EBUSY)
1618 			dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n",
1619 					urb, retval);
1620 		usb_put_dev(udev);
1621 	}
1622 	return retval;
1623 }
1624 
1625 /*-------------------------------------------------------------------------*/
1626 
1627 static void __usb_hcd_giveback_urb(struct urb *urb)
1628 {
1629 	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1630 	struct usb_anchor *anchor = urb->anchor;
1631 	int status = urb->unlinked;
1632 
1633 	urb->hcpriv = NULL;
1634 	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1635 	    urb->actual_length < urb->transfer_buffer_length &&
1636 	    !status))
1637 		status = -EREMOTEIO;
1638 
1639 	unmap_urb_for_dma(hcd, urb);
1640 	usbmon_urb_complete(&hcd->self, urb, status);
1641 	usb_anchor_suspend_wakeups(anchor);
1642 	usb_unanchor_urb(urb);
1643 	if (likely(status == 0))
1644 		usb_led_activity(USB_LED_EVENT_HOST);
1645 
1646 	/* pass ownership to the completion handler */
1647 	urb->status = status;
1648 	urb->complete(urb);
1649 
1650 	usb_anchor_resume_wakeups(anchor);
1651 	atomic_dec(&urb->use_count);
1652 	if (unlikely(atomic_read(&urb->reject)))
1653 		wake_up(&usb_kill_urb_queue);
1654 	usb_put_urb(urb);
1655 }
1656 
1657 static void usb_giveback_urb_bh(unsigned long param)
1658 {
1659 	struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param;
1660 	struct list_head local_list;
1661 
1662 	spin_lock_irq(&bh->lock);
1663 	bh->running = true;
1664  restart:
1665 	list_replace_init(&bh->head, &local_list);
1666 	spin_unlock_irq(&bh->lock);
1667 
1668 	while (!list_empty(&local_list)) {
1669 		struct urb *urb;
1670 
1671 		urb = list_entry(local_list.next, struct urb, urb_list);
1672 		list_del_init(&urb->urb_list);
1673 		bh->completing_ep = urb->ep;
1674 		__usb_hcd_giveback_urb(urb);
1675 		bh->completing_ep = NULL;
1676 	}
1677 
1678 	/* check if there are new URBs to giveback */
1679 	spin_lock_irq(&bh->lock);
1680 	if (!list_empty(&bh->head))
1681 		goto restart;
1682 	bh->running = false;
1683 	spin_unlock_irq(&bh->lock);
1684 }
1685 
1686 /**
1687  * usb_hcd_giveback_urb - return URB from HCD to device driver
1688  * @hcd: host controller returning the URB
1689  * @urb: urb being returned to the USB device driver.
1690  * @status: completion status code for the URB.
1691  * Context: in_interrupt()
1692  *
1693  * This hands the URB from HCD to its USB device driver, using its
1694  * completion function.  The HCD has freed all per-urb resources
1695  * (and is done using urb->hcpriv).  It also released all HCD locks;
1696  * the device driver won't cause problems if it frees, modifies,
1697  * or resubmits this URB.
1698  *
1699  * If @urb was unlinked, the value of @status will be overridden by
1700  * @urb->unlinked.  Erroneous short transfers are detected in case
1701  * the HCD hasn't checked for them.
1702  */
1703 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1704 {
1705 	struct giveback_urb_bh *bh;
1706 	bool running, high_prio_bh;
1707 
1708 	/* pass status to tasklet via unlinked */
1709 	if (likely(!urb->unlinked))
1710 		urb->unlinked = status;
1711 
1712 	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1713 		__usb_hcd_giveback_urb(urb);
1714 		return;
1715 	}
1716 
1717 	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
1718 		bh = &hcd->high_prio_bh;
1719 		high_prio_bh = true;
1720 	} else {
1721 		bh = &hcd->low_prio_bh;
1722 		high_prio_bh = false;
1723 	}
1724 
1725 	spin_lock(&bh->lock);
1726 	list_add_tail(&urb->urb_list, &bh->head);
1727 	running = bh->running;
1728 	spin_unlock(&bh->lock);
1729 
1730 	if (running)
1731 		;
1732 	else if (high_prio_bh)
1733 		tasklet_hi_schedule(&bh->bh);
1734 	else
1735 		tasklet_schedule(&bh->bh);
1736 }
1737 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1738 
1739 /*-------------------------------------------------------------------------*/
1740 
1741 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1742  * queue to drain completely.  The caller must first insure that no more
1743  * URBs can be submitted for this endpoint.
1744  */
1745 void usb_hcd_flush_endpoint(struct usb_device *udev,
1746 		struct usb_host_endpoint *ep)
1747 {
1748 	struct usb_hcd		*hcd;
1749 	struct urb		*urb;
1750 
1751 	if (!ep)
1752 		return;
1753 	might_sleep();
1754 	hcd = bus_to_hcd(udev->bus);
1755 
1756 	/* No more submits can occur */
1757 	spin_lock_irq(&hcd_urb_list_lock);
1758 rescan:
1759 	list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) {
1760 		int	is_in;
1761 
1762 		if (urb->unlinked)
1763 			continue;
1764 		usb_get_urb (urb);
1765 		is_in = usb_urb_dir_in(urb);
1766 		spin_unlock(&hcd_urb_list_lock);
1767 
1768 		/* kick hcd */
1769 		unlink1(hcd, urb, -ESHUTDOWN);
1770 		dev_dbg (hcd->self.controller,
1771 			"shutdown urb %pK ep%d%s-%s\n",
1772 			urb, usb_endpoint_num(&ep->desc),
1773 			is_in ? "in" : "out",
1774 			usb_ep_type_string(usb_endpoint_type(&ep->desc)));
1775 		usb_put_urb (urb);
1776 
1777 		/* list contents may have changed */
1778 		spin_lock(&hcd_urb_list_lock);
1779 		goto rescan;
1780 	}
1781 	spin_unlock_irq(&hcd_urb_list_lock);
1782 
1783 	/* Wait until the endpoint queue is completely empty */
1784 	while (!list_empty (&ep->urb_list)) {
1785 		spin_lock_irq(&hcd_urb_list_lock);
1786 
1787 		/* The list may have changed while we acquired the spinlock */
1788 		urb = NULL;
1789 		if (!list_empty (&ep->urb_list)) {
1790 			urb = list_entry (ep->urb_list.prev, struct urb,
1791 					urb_list);
1792 			usb_get_urb (urb);
1793 		}
1794 		spin_unlock_irq(&hcd_urb_list_lock);
1795 
1796 		if (urb) {
1797 			usb_kill_urb (urb);
1798 			usb_put_urb (urb);
1799 		}
1800 	}
1801 }
1802 
1803 /**
1804  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1805  *				the bus bandwidth
1806  * @udev: target &usb_device
1807  * @new_config: new configuration to install
1808  * @cur_alt: the current alternate interface setting
1809  * @new_alt: alternate interface setting that is being installed
1810  *
1811  * To change configurations, pass in the new configuration in new_config,
1812  * and pass NULL for cur_alt and new_alt.
1813  *
1814  * To reset a device's configuration (put the device in the ADDRESSED state),
1815  * pass in NULL for new_config, cur_alt, and new_alt.
1816  *
1817  * To change alternate interface settings, pass in NULL for new_config,
1818  * pass in the current alternate interface setting in cur_alt,
1819  * and pass in the new alternate interface setting in new_alt.
1820  *
1821  * Return: An error if the requested bandwidth change exceeds the
1822  * bus bandwidth or host controller internal resources.
1823  */
1824 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1825 		struct usb_host_config *new_config,
1826 		struct usb_host_interface *cur_alt,
1827 		struct usb_host_interface *new_alt)
1828 {
1829 	int num_intfs, i, j;
1830 	struct usb_host_interface *alt = NULL;
1831 	int ret = 0;
1832 	struct usb_hcd *hcd;
1833 	struct usb_host_endpoint *ep;
1834 
1835 	hcd = bus_to_hcd(udev->bus);
1836 	if (!hcd->driver->check_bandwidth)
1837 		return 0;
1838 
1839 	/* Configuration is being removed - set configuration 0 */
1840 	if (!new_config && !cur_alt) {
1841 		for (i = 1; i < 16; ++i) {
1842 			ep = udev->ep_out[i];
1843 			if (ep)
1844 				hcd->driver->drop_endpoint(hcd, udev, ep);
1845 			ep = udev->ep_in[i];
1846 			if (ep)
1847 				hcd->driver->drop_endpoint(hcd, udev, ep);
1848 		}
1849 		hcd->driver->check_bandwidth(hcd, udev);
1850 		return 0;
1851 	}
1852 	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1853 	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1854 	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1855 	 * ok to exclude it.
1856 	 */
1857 	if (new_config) {
1858 		num_intfs = new_config->desc.bNumInterfaces;
1859 		/* Remove endpoints (except endpoint 0, which is always on the
1860 		 * schedule) from the old config from the schedule
1861 		 */
1862 		for (i = 1; i < 16; ++i) {
1863 			ep = udev->ep_out[i];
1864 			if (ep) {
1865 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1866 				if (ret < 0)
1867 					goto reset;
1868 			}
1869 			ep = udev->ep_in[i];
1870 			if (ep) {
1871 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1872 				if (ret < 0)
1873 					goto reset;
1874 			}
1875 		}
1876 		for (i = 0; i < num_intfs; ++i) {
1877 			struct usb_host_interface *first_alt;
1878 			int iface_num;
1879 
1880 			first_alt = &new_config->intf_cache[i]->altsetting[0];
1881 			iface_num = first_alt->desc.bInterfaceNumber;
1882 			/* Set up endpoints for alternate interface setting 0 */
1883 			alt = usb_find_alt_setting(new_config, iface_num, 0);
1884 			if (!alt)
1885 				/* No alt setting 0? Pick the first setting. */
1886 				alt = first_alt;
1887 
1888 			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1889 				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1890 				if (ret < 0)
1891 					goto reset;
1892 			}
1893 		}
1894 	}
1895 	if (cur_alt && new_alt) {
1896 		struct usb_interface *iface = usb_ifnum_to_if(udev,
1897 				cur_alt->desc.bInterfaceNumber);
1898 
1899 		if (!iface)
1900 			return -EINVAL;
1901 		if (iface->resetting_device) {
1902 			/*
1903 			 * The USB core just reset the device, so the xHCI host
1904 			 * and the device will think alt setting 0 is installed.
1905 			 * However, the USB core will pass in the alternate
1906 			 * setting installed before the reset as cur_alt.  Dig
1907 			 * out the alternate setting 0 structure, or the first
1908 			 * alternate setting if a broken device doesn't have alt
1909 			 * setting 0.
1910 			 */
1911 			cur_alt = usb_altnum_to_altsetting(iface, 0);
1912 			if (!cur_alt)
1913 				cur_alt = &iface->altsetting[0];
1914 		}
1915 
1916 		/* Drop all the endpoints in the current alt setting */
1917 		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
1918 			ret = hcd->driver->drop_endpoint(hcd, udev,
1919 					&cur_alt->endpoint[i]);
1920 			if (ret < 0)
1921 				goto reset;
1922 		}
1923 		/* Add all the endpoints in the new alt setting */
1924 		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
1925 			ret = hcd->driver->add_endpoint(hcd, udev,
1926 					&new_alt->endpoint[i]);
1927 			if (ret < 0)
1928 				goto reset;
1929 		}
1930 	}
1931 	ret = hcd->driver->check_bandwidth(hcd, udev);
1932 reset:
1933 	if (ret < 0)
1934 		hcd->driver->reset_bandwidth(hcd, udev);
1935 	return ret;
1936 }
1937 
1938 /* Disables the endpoint: synchronizes with the hcd to make sure all
1939  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
1940  * have been called previously.  Use for set_configuration, set_interface,
1941  * driver removal, physical disconnect.
1942  *
1943  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
1944  * type, maxpacket size, toggle, halt status, and scheduling.
1945  */
1946 void usb_hcd_disable_endpoint(struct usb_device *udev,
1947 		struct usb_host_endpoint *ep)
1948 {
1949 	struct usb_hcd		*hcd;
1950 
1951 	might_sleep();
1952 	hcd = bus_to_hcd(udev->bus);
1953 	if (hcd->driver->endpoint_disable)
1954 		hcd->driver->endpoint_disable(hcd, ep);
1955 }
1956 
1957 /**
1958  * usb_hcd_reset_endpoint - reset host endpoint state
1959  * @udev: USB device.
1960  * @ep:   the endpoint to reset.
1961  *
1962  * Resets any host endpoint state such as the toggle bit, sequence
1963  * number and current window.
1964  */
1965 void usb_hcd_reset_endpoint(struct usb_device *udev,
1966 			    struct usb_host_endpoint *ep)
1967 {
1968 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1969 
1970 	if (hcd->driver->endpoint_reset)
1971 		hcd->driver->endpoint_reset(hcd, ep);
1972 	else {
1973 		int epnum = usb_endpoint_num(&ep->desc);
1974 		int is_out = usb_endpoint_dir_out(&ep->desc);
1975 		int is_control = usb_endpoint_xfer_control(&ep->desc);
1976 
1977 		usb_settoggle(udev, epnum, is_out, 0);
1978 		if (is_control)
1979 			usb_settoggle(udev, epnum, !is_out, 0);
1980 	}
1981 }
1982 
1983 /**
1984  * usb_alloc_streams - allocate bulk endpoint stream IDs.
1985  * @interface:		alternate setting that includes all endpoints.
1986  * @eps:		array of endpoints that need streams.
1987  * @num_eps:		number of endpoints in the array.
1988  * @num_streams:	number of streams to allocate.
1989  * @mem_flags:		flags hcd should use to allocate memory.
1990  *
1991  * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
1992  * Drivers may queue multiple transfers to different stream IDs, which may
1993  * complete in a different order than they were queued.
1994  *
1995  * Return: On success, the number of allocated streams. On failure, a negative
1996  * error code.
1997  */
1998 int usb_alloc_streams(struct usb_interface *interface,
1999 		struct usb_host_endpoint **eps, unsigned int num_eps,
2000 		unsigned int num_streams, gfp_t mem_flags)
2001 {
2002 	struct usb_hcd *hcd;
2003 	struct usb_device *dev;
2004 	int i, ret;
2005 
2006 	dev = interface_to_usbdev(interface);
2007 	hcd = bus_to_hcd(dev->bus);
2008 	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2009 		return -EINVAL;
2010 	if (dev->speed < USB_SPEED_SUPER)
2011 		return -EINVAL;
2012 	if (dev->state < USB_STATE_CONFIGURED)
2013 		return -ENODEV;
2014 
2015 	for (i = 0; i < num_eps; i++) {
2016 		/* Streams only apply to bulk endpoints. */
2017 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2018 			return -EINVAL;
2019 		/* Re-alloc is not allowed */
2020 		if (eps[i]->streams)
2021 			return -EINVAL;
2022 	}
2023 
2024 	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2025 			num_streams, mem_flags);
2026 	if (ret < 0)
2027 		return ret;
2028 
2029 	for (i = 0; i < num_eps; i++)
2030 		eps[i]->streams = ret;
2031 
2032 	return ret;
2033 }
2034 EXPORT_SYMBOL_GPL(usb_alloc_streams);
2035 
2036 /**
2037  * usb_free_streams - free bulk endpoint stream IDs.
2038  * @interface:	alternate setting that includes all endpoints.
2039  * @eps:	array of endpoints to remove streams from.
2040  * @num_eps:	number of endpoints in the array.
2041  * @mem_flags:	flags hcd should use to allocate memory.
2042  *
2043  * Reverts a group of bulk endpoints back to not using stream IDs.
2044  * Can fail if we are given bad arguments, or HCD is broken.
2045  *
2046  * Return: 0 on success. On failure, a negative error code.
2047  */
2048 int usb_free_streams(struct usb_interface *interface,
2049 		struct usb_host_endpoint **eps, unsigned int num_eps,
2050 		gfp_t mem_flags)
2051 {
2052 	struct usb_hcd *hcd;
2053 	struct usb_device *dev;
2054 	int i, ret;
2055 
2056 	dev = interface_to_usbdev(interface);
2057 	hcd = bus_to_hcd(dev->bus);
2058 	if (dev->speed < USB_SPEED_SUPER)
2059 		return -EINVAL;
2060 
2061 	/* Double-free is not allowed */
2062 	for (i = 0; i < num_eps; i++)
2063 		if (!eps[i] || !eps[i]->streams)
2064 			return -EINVAL;
2065 
2066 	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2067 	if (ret < 0)
2068 		return ret;
2069 
2070 	for (i = 0; i < num_eps; i++)
2071 		eps[i]->streams = 0;
2072 
2073 	return ret;
2074 }
2075 EXPORT_SYMBOL_GPL(usb_free_streams);
2076 
2077 /* Protect against drivers that try to unlink URBs after the device
2078  * is gone, by waiting until all unlinks for @udev are finished.
2079  * Since we don't currently track URBs by device, simply wait until
2080  * nothing is running in the locked region of usb_hcd_unlink_urb().
2081  */
2082 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2083 {
2084 	spin_lock_irq(&hcd_urb_unlink_lock);
2085 	spin_unlock_irq(&hcd_urb_unlink_lock);
2086 }
2087 
2088 /*-------------------------------------------------------------------------*/
2089 
2090 /* called in any context */
2091 int usb_hcd_get_frame_number (struct usb_device *udev)
2092 {
2093 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
2094 
2095 	if (!HCD_RH_RUNNING(hcd))
2096 		return -ESHUTDOWN;
2097 	return hcd->driver->get_frame_number (hcd);
2098 }
2099 
2100 /*-------------------------------------------------------------------------*/
2101 
2102 #ifdef	CONFIG_PM
2103 
2104 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2105 {
2106 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2107 	int		status;
2108 	int		old_state = hcd->state;
2109 
2110 	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2111 			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2112 			rhdev->do_remote_wakeup);
2113 	if (HCD_DEAD(hcd)) {
2114 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2115 		return 0;
2116 	}
2117 
2118 	if (!hcd->driver->bus_suspend) {
2119 		status = -ENOENT;
2120 	} else {
2121 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2122 		hcd->state = HC_STATE_QUIESCING;
2123 		status = hcd->driver->bus_suspend(hcd);
2124 	}
2125 	if (status == 0) {
2126 		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2127 		hcd->state = HC_STATE_SUSPENDED;
2128 
2129 		if (!PMSG_IS_AUTO(msg))
2130 			usb_phy_roothub_suspend(hcd->self.sysdev,
2131 						hcd->phy_roothub);
2132 
2133 		/* Did we race with a root-hub wakeup event? */
2134 		if (rhdev->do_remote_wakeup) {
2135 			char	buffer[6];
2136 
2137 			status = hcd->driver->hub_status_data(hcd, buffer);
2138 			if (status != 0) {
2139 				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2140 				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2141 				status = -EBUSY;
2142 			}
2143 		}
2144 	} else {
2145 		spin_lock_irq(&hcd_root_hub_lock);
2146 		if (!HCD_DEAD(hcd)) {
2147 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2148 			hcd->state = old_state;
2149 		}
2150 		spin_unlock_irq(&hcd_root_hub_lock);
2151 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2152 				"suspend", status);
2153 	}
2154 	return status;
2155 }
2156 
2157 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2158 {
2159 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2160 	int		status;
2161 	int		old_state = hcd->state;
2162 
2163 	dev_dbg(&rhdev->dev, "usb %sresume\n",
2164 			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2165 	if (HCD_DEAD(hcd)) {
2166 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2167 		return 0;
2168 	}
2169 
2170 	if (!PMSG_IS_AUTO(msg)) {
2171 		status = usb_phy_roothub_resume(hcd->self.sysdev,
2172 						hcd->phy_roothub);
2173 		if (status)
2174 			return status;
2175 	}
2176 
2177 	if (!hcd->driver->bus_resume)
2178 		return -ENOENT;
2179 	if (HCD_RH_RUNNING(hcd))
2180 		return 0;
2181 
2182 	hcd->state = HC_STATE_RESUMING;
2183 	status = hcd->driver->bus_resume(hcd);
2184 	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2185 	if (status == 0)
2186 		status = usb_phy_roothub_calibrate(hcd->phy_roothub);
2187 
2188 	if (status == 0) {
2189 		struct usb_device *udev;
2190 		int port1;
2191 
2192 		spin_lock_irq(&hcd_root_hub_lock);
2193 		if (!HCD_DEAD(hcd)) {
2194 			usb_set_device_state(rhdev, rhdev->actconfig
2195 					? USB_STATE_CONFIGURED
2196 					: USB_STATE_ADDRESS);
2197 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2198 			hcd->state = HC_STATE_RUNNING;
2199 		}
2200 		spin_unlock_irq(&hcd_root_hub_lock);
2201 
2202 		/*
2203 		 * Check whether any of the enabled ports on the root hub are
2204 		 * unsuspended.  If they are then a TRSMRCY delay is needed
2205 		 * (this is what the USB-2 spec calls a "global resume").
2206 		 * Otherwise we can skip the delay.
2207 		 */
2208 		usb_hub_for_each_child(rhdev, port1, udev) {
2209 			if (udev->state != USB_STATE_NOTATTACHED &&
2210 					!udev->port_is_suspended) {
2211 				usleep_range(10000, 11000);	/* TRSMRCY */
2212 				break;
2213 			}
2214 		}
2215 	} else {
2216 		hcd->state = old_state;
2217 		usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub);
2218 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2219 				"resume", status);
2220 		if (status != -ESHUTDOWN)
2221 			usb_hc_died(hcd);
2222 	}
2223 	return status;
2224 }
2225 
2226 /* Workqueue routine for root-hub remote wakeup */
2227 static void hcd_resume_work(struct work_struct *work)
2228 {
2229 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2230 	struct usb_device *udev = hcd->self.root_hub;
2231 
2232 	usb_remote_wakeup(udev);
2233 }
2234 
2235 /**
2236  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2237  * @hcd: host controller for this root hub
2238  *
2239  * The USB host controller calls this function when its root hub is
2240  * suspended (with the remote wakeup feature enabled) and a remote
2241  * wakeup request is received.  The routine submits a workqueue request
2242  * to resume the root hub (that is, manage its downstream ports again).
2243  */
2244 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2245 {
2246 	unsigned long flags;
2247 
2248 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2249 	if (hcd->rh_registered) {
2250 		pm_wakeup_event(&hcd->self.root_hub->dev, 0);
2251 		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2252 		queue_work(pm_wq, &hcd->wakeup_work);
2253 	}
2254 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2255 }
2256 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2257 
2258 #endif	/* CONFIG_PM */
2259 
2260 /*-------------------------------------------------------------------------*/
2261 
2262 #ifdef	CONFIG_USB_OTG
2263 
2264 /**
2265  * usb_bus_start_enum - start immediate enumeration (for OTG)
2266  * @bus: the bus (must use hcd framework)
2267  * @port_num: 1-based number of port; usually bus->otg_port
2268  * Context: in_interrupt()
2269  *
2270  * Starts enumeration, with an immediate reset followed later by
2271  * hub_wq identifying and possibly configuring the device.
2272  * This is needed by OTG controller drivers, where it helps meet
2273  * HNP protocol timing requirements for starting a port reset.
2274  *
2275  * Return: 0 if successful.
2276  */
2277 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2278 {
2279 	struct usb_hcd		*hcd;
2280 	int			status = -EOPNOTSUPP;
2281 
2282 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2283 	 * boards with root hubs hooked up to internal devices (instead of
2284 	 * just the OTG port) may need more attention to resetting...
2285 	 */
2286 	hcd = bus_to_hcd(bus);
2287 	if (port_num && hcd->driver->start_port_reset)
2288 		status = hcd->driver->start_port_reset(hcd, port_num);
2289 
2290 	/* allocate hub_wq shortly after (first) root port reset finishes;
2291 	 * it may issue others, until at least 50 msecs have passed.
2292 	 */
2293 	if (status == 0)
2294 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2295 	return status;
2296 }
2297 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2298 
2299 #endif
2300 
2301 /*-------------------------------------------------------------------------*/
2302 
2303 /**
2304  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2305  * @irq: the IRQ being raised
2306  * @__hcd: pointer to the HCD whose IRQ is being signaled
2307  *
2308  * If the controller isn't HALTed, calls the driver's irq handler.
2309  * Checks whether the controller is now dead.
2310  *
2311  * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2312  */
2313 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2314 {
2315 	struct usb_hcd		*hcd = __hcd;
2316 	irqreturn_t		rc;
2317 
2318 	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2319 		rc = IRQ_NONE;
2320 	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2321 		rc = IRQ_NONE;
2322 	else
2323 		rc = IRQ_HANDLED;
2324 
2325 	return rc;
2326 }
2327 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2328 
2329 /*-------------------------------------------------------------------------*/
2330 
2331 /* Workqueue routine for when the root-hub has died. */
2332 static void hcd_died_work(struct work_struct *work)
2333 {
2334 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, died_work);
2335 	static char *env[] = {
2336 		"ERROR=DEAD",
2337 		NULL
2338 	};
2339 
2340 	/* Notify user space that the host controller has died */
2341 	kobject_uevent_env(&hcd->self.root_hub->dev.kobj, KOBJ_OFFLINE, env);
2342 }
2343 
2344 /**
2345  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2346  * @hcd: pointer to the HCD representing the controller
2347  *
2348  * This is called by bus glue to report a USB host controller that died
2349  * while operations may still have been pending.  It's called automatically
2350  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2351  *
2352  * Only call this function with the primary HCD.
2353  */
2354 void usb_hc_died (struct usb_hcd *hcd)
2355 {
2356 	unsigned long flags;
2357 
2358 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2359 
2360 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2361 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2362 	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2363 	if (hcd->rh_registered) {
2364 		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2365 
2366 		/* make hub_wq clean up old urbs and devices */
2367 		usb_set_device_state (hcd->self.root_hub,
2368 				USB_STATE_NOTATTACHED);
2369 		usb_kick_hub_wq(hcd->self.root_hub);
2370 	}
2371 	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2372 		hcd = hcd->shared_hcd;
2373 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2374 		set_bit(HCD_FLAG_DEAD, &hcd->flags);
2375 		if (hcd->rh_registered) {
2376 			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2377 
2378 			/* make hub_wq clean up old urbs and devices */
2379 			usb_set_device_state(hcd->self.root_hub,
2380 					USB_STATE_NOTATTACHED);
2381 			usb_kick_hub_wq(hcd->self.root_hub);
2382 		}
2383 	}
2384 
2385 	/* Handle the case where this function gets called with a shared HCD */
2386 	if (usb_hcd_is_primary_hcd(hcd))
2387 		schedule_work(&hcd->died_work);
2388 	else
2389 		schedule_work(&hcd->primary_hcd->died_work);
2390 
2391 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2392 	/* Make sure that the other roothub is also deallocated. */
2393 }
2394 EXPORT_SYMBOL_GPL (usb_hc_died);
2395 
2396 /*-------------------------------------------------------------------------*/
2397 
2398 static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2399 {
2400 
2401 	spin_lock_init(&bh->lock);
2402 	INIT_LIST_HEAD(&bh->head);
2403 	tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh);
2404 }
2405 
2406 struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
2407 		struct device *sysdev, struct device *dev, const char *bus_name,
2408 		struct usb_hcd *primary_hcd)
2409 {
2410 	struct usb_hcd *hcd;
2411 
2412 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2413 	if (!hcd)
2414 		return NULL;
2415 	if (primary_hcd == NULL) {
2416 		hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex),
2417 				GFP_KERNEL);
2418 		if (!hcd->address0_mutex) {
2419 			kfree(hcd);
2420 			dev_dbg(dev, "hcd address0 mutex alloc failed\n");
2421 			return NULL;
2422 		}
2423 		mutex_init(hcd->address0_mutex);
2424 		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2425 				GFP_KERNEL);
2426 		if (!hcd->bandwidth_mutex) {
2427 			kfree(hcd->address0_mutex);
2428 			kfree(hcd);
2429 			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2430 			return NULL;
2431 		}
2432 		mutex_init(hcd->bandwidth_mutex);
2433 		dev_set_drvdata(dev, hcd);
2434 	} else {
2435 		mutex_lock(&usb_port_peer_mutex);
2436 		hcd->address0_mutex = primary_hcd->address0_mutex;
2437 		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2438 		hcd->primary_hcd = primary_hcd;
2439 		primary_hcd->primary_hcd = primary_hcd;
2440 		hcd->shared_hcd = primary_hcd;
2441 		primary_hcd->shared_hcd = hcd;
2442 		mutex_unlock(&usb_port_peer_mutex);
2443 	}
2444 
2445 	kref_init(&hcd->kref);
2446 
2447 	usb_bus_init(&hcd->self);
2448 	hcd->self.controller = dev;
2449 	hcd->self.sysdev = sysdev;
2450 	hcd->self.bus_name = bus_name;
2451 
2452 	timer_setup(&hcd->rh_timer, rh_timer_func, 0);
2453 #ifdef CONFIG_PM
2454 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2455 #endif
2456 
2457 	INIT_WORK(&hcd->died_work, hcd_died_work);
2458 
2459 	hcd->driver = driver;
2460 	hcd->speed = driver->flags & HCD_MASK;
2461 	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2462 			"USB Host Controller";
2463 	return hcd;
2464 }
2465 EXPORT_SYMBOL_GPL(__usb_create_hcd);
2466 
2467 /**
2468  * usb_create_shared_hcd - create and initialize an HCD structure
2469  * @driver: HC driver that will use this hcd
2470  * @dev: device for this HC, stored in hcd->self.controller
2471  * @bus_name: value to store in hcd->self.bus_name
2472  * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2473  *              PCI device.  Only allocate certain resources for the primary HCD
2474  * Context: !in_interrupt()
2475  *
2476  * Allocate a struct usb_hcd, with extra space at the end for the
2477  * HC driver's private data.  Initialize the generic members of the
2478  * hcd structure.
2479  *
2480  * Return: On success, a pointer to the created and initialized HCD structure.
2481  * On failure (e.g. if memory is unavailable), %NULL.
2482  */
2483 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2484 		struct device *dev, const char *bus_name,
2485 		struct usb_hcd *primary_hcd)
2486 {
2487 	return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd);
2488 }
2489 EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2490 
2491 /**
2492  * usb_create_hcd - create and initialize an HCD structure
2493  * @driver: HC driver that will use this hcd
2494  * @dev: device for this HC, stored in hcd->self.controller
2495  * @bus_name: value to store in hcd->self.bus_name
2496  * Context: !in_interrupt()
2497  *
2498  * Allocate a struct usb_hcd, with extra space at the end for the
2499  * HC driver's private data.  Initialize the generic members of the
2500  * hcd structure.
2501  *
2502  * Return: On success, a pointer to the created and initialized HCD
2503  * structure. On failure (e.g. if memory is unavailable), %NULL.
2504  */
2505 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2506 		struct device *dev, const char *bus_name)
2507 {
2508 	return __usb_create_hcd(driver, dev, dev, bus_name, NULL);
2509 }
2510 EXPORT_SYMBOL_GPL(usb_create_hcd);
2511 
2512 /*
2513  * Roothubs that share one PCI device must also share the bandwidth mutex.
2514  * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2515  * deallocated.
2516  *
2517  * Make sure to deallocate the bandwidth_mutex only when the last HCD is
2518  * freed.  When hcd_release() is called for either hcd in a peer set,
2519  * invalidate the peer's ->shared_hcd and ->primary_hcd pointers.
2520  */
2521 static void hcd_release(struct kref *kref)
2522 {
2523 	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2524 
2525 	mutex_lock(&usb_port_peer_mutex);
2526 	if (hcd->shared_hcd) {
2527 		struct usb_hcd *peer = hcd->shared_hcd;
2528 
2529 		peer->shared_hcd = NULL;
2530 		peer->primary_hcd = NULL;
2531 	} else {
2532 		kfree(hcd->address0_mutex);
2533 		kfree(hcd->bandwidth_mutex);
2534 	}
2535 	mutex_unlock(&usb_port_peer_mutex);
2536 	kfree(hcd);
2537 }
2538 
2539 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2540 {
2541 	if (hcd)
2542 		kref_get (&hcd->kref);
2543 	return hcd;
2544 }
2545 EXPORT_SYMBOL_GPL(usb_get_hcd);
2546 
2547 void usb_put_hcd (struct usb_hcd *hcd)
2548 {
2549 	if (hcd)
2550 		kref_put (&hcd->kref, hcd_release);
2551 }
2552 EXPORT_SYMBOL_GPL(usb_put_hcd);
2553 
2554 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2555 {
2556 	if (!hcd->primary_hcd)
2557 		return 1;
2558 	return hcd == hcd->primary_hcd;
2559 }
2560 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2561 
2562 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2563 {
2564 	if (!hcd->driver->find_raw_port_number)
2565 		return port1;
2566 
2567 	return hcd->driver->find_raw_port_number(hcd, port1);
2568 }
2569 
2570 static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2571 		unsigned int irqnum, unsigned long irqflags)
2572 {
2573 	int retval;
2574 
2575 	if (hcd->driver->irq) {
2576 
2577 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2578 				hcd->driver->description, hcd->self.busnum);
2579 		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2580 				hcd->irq_descr, hcd);
2581 		if (retval != 0) {
2582 			dev_err(hcd->self.controller,
2583 					"request interrupt %d failed\n",
2584 					irqnum);
2585 			return retval;
2586 		}
2587 		hcd->irq = irqnum;
2588 		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2589 				(hcd->driver->flags & HCD_MEMORY) ?
2590 					"io mem" : "io base",
2591 					(unsigned long long)hcd->rsrc_start);
2592 	} else {
2593 		hcd->irq = 0;
2594 		if (hcd->rsrc_start)
2595 			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2596 					(hcd->driver->flags & HCD_MEMORY) ?
2597 					"io mem" : "io base",
2598 					(unsigned long long)hcd->rsrc_start);
2599 	}
2600 	return 0;
2601 }
2602 
2603 /*
2604  * Before we free this root hub, flush in-flight peering attempts
2605  * and disable peer lookups
2606  */
2607 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2608 {
2609 	struct usb_device *rhdev;
2610 
2611 	mutex_lock(&usb_port_peer_mutex);
2612 	rhdev = hcd->self.root_hub;
2613 	hcd->self.root_hub = NULL;
2614 	mutex_unlock(&usb_port_peer_mutex);
2615 	usb_put_dev(rhdev);
2616 }
2617 
2618 /**
2619  * usb_add_hcd - finish generic HCD structure initialization and register
2620  * @hcd: the usb_hcd structure to initialize
2621  * @irqnum: Interrupt line to allocate
2622  * @irqflags: Interrupt type flags
2623  *
2624  * Finish the remaining parts of generic HCD initialization: allocate the
2625  * buffers of consistent memory, register the bus, request the IRQ line,
2626  * and call the driver's reset() and start() routines.
2627  */
2628 int usb_add_hcd(struct usb_hcd *hcd,
2629 		unsigned int irqnum, unsigned long irqflags)
2630 {
2631 	int retval;
2632 	struct usb_device *rhdev;
2633 
2634 	if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) {
2635 		hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev);
2636 		if (IS_ERR(hcd->phy_roothub))
2637 			return PTR_ERR(hcd->phy_roothub);
2638 
2639 		retval = usb_phy_roothub_init(hcd->phy_roothub);
2640 		if (retval)
2641 			return retval;
2642 
2643 		retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2644 						  PHY_MODE_USB_HOST_SS);
2645 		if (retval)
2646 			retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2647 							  PHY_MODE_USB_HOST);
2648 		if (retval)
2649 			goto err_usb_phy_roothub_power_on;
2650 
2651 		retval = usb_phy_roothub_power_on(hcd->phy_roothub);
2652 		if (retval)
2653 			goto err_usb_phy_roothub_power_on;
2654 	}
2655 
2656 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2657 
2658 	switch (authorized_default) {
2659 	case USB_AUTHORIZE_NONE:
2660 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_NONE;
2661 		break;
2662 
2663 	case USB_AUTHORIZE_ALL:
2664 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_ALL;
2665 		break;
2666 
2667 	case USB_AUTHORIZE_INTERNAL:
2668 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_INTERNAL;
2669 		break;
2670 
2671 	case USB_AUTHORIZE_WIRED:
2672 	default:
2673 		hcd->dev_policy = hcd->wireless ?
2674 			USB_DEVICE_AUTHORIZE_NONE : USB_DEVICE_AUTHORIZE_ALL;
2675 		break;
2676 	}
2677 
2678 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2679 
2680 	/* per default all interfaces are authorized */
2681 	set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
2682 
2683 	/* HC is in reset state, but accessible.  Now do the one-time init,
2684 	 * bottom up so that hcds can customize the root hubs before hub_wq
2685 	 * starts talking to them.  (Note, bus id is assigned early too.)
2686 	 */
2687 	retval = hcd_buffer_create(hcd);
2688 	if (retval != 0) {
2689 		dev_dbg(hcd->self.sysdev, "pool alloc failed\n");
2690 		goto err_create_buf;
2691 	}
2692 
2693 	retval = usb_register_bus(&hcd->self);
2694 	if (retval < 0)
2695 		goto err_register_bus;
2696 
2697 	rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2698 	if (rhdev == NULL) {
2699 		dev_err(hcd->self.sysdev, "unable to allocate root hub\n");
2700 		retval = -ENOMEM;
2701 		goto err_allocate_root_hub;
2702 	}
2703 	mutex_lock(&usb_port_peer_mutex);
2704 	hcd->self.root_hub = rhdev;
2705 	mutex_unlock(&usb_port_peer_mutex);
2706 
2707 	rhdev->rx_lanes = 1;
2708 	rhdev->tx_lanes = 1;
2709 
2710 	switch (hcd->speed) {
2711 	case HCD_USB11:
2712 		rhdev->speed = USB_SPEED_FULL;
2713 		break;
2714 	case HCD_USB2:
2715 		rhdev->speed = USB_SPEED_HIGH;
2716 		break;
2717 	case HCD_USB25:
2718 		rhdev->speed = USB_SPEED_WIRELESS;
2719 		break;
2720 	case HCD_USB3:
2721 		rhdev->speed = USB_SPEED_SUPER;
2722 		break;
2723 	case HCD_USB32:
2724 		rhdev->rx_lanes = 2;
2725 		rhdev->tx_lanes = 2;
2726 		/* fall through */
2727 	case HCD_USB31:
2728 		rhdev->speed = USB_SPEED_SUPER_PLUS;
2729 		break;
2730 	default:
2731 		retval = -EINVAL;
2732 		goto err_set_rh_speed;
2733 	}
2734 
2735 	/* wakeup flag init defaults to "everything works" for root hubs,
2736 	 * but drivers can override it in reset() if needed, along with
2737 	 * recording the overall controller's system wakeup capability.
2738 	 */
2739 	device_set_wakeup_capable(&rhdev->dev, 1);
2740 
2741 	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2742 	 * registered.  But since the controller can die at any time,
2743 	 * let's initialize the flag before touching the hardware.
2744 	 */
2745 	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2746 
2747 	/* "reset" is misnamed; its role is now one-time init. the controller
2748 	 * should already have been reset (and boot firmware kicked off etc).
2749 	 */
2750 	if (hcd->driver->reset) {
2751 		retval = hcd->driver->reset(hcd);
2752 		if (retval < 0) {
2753 			dev_err(hcd->self.controller, "can't setup: %d\n",
2754 					retval);
2755 			goto err_hcd_driver_setup;
2756 		}
2757 	}
2758 	hcd->rh_pollable = 1;
2759 
2760 	retval = usb_phy_roothub_calibrate(hcd->phy_roothub);
2761 	if (retval)
2762 		goto err_hcd_driver_setup;
2763 
2764 	/* NOTE: root hub and controller capabilities may not be the same */
2765 	if (device_can_wakeup(hcd->self.controller)
2766 			&& device_can_wakeup(&hcd->self.root_hub->dev))
2767 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2768 
2769 	/* initialize tasklets */
2770 	init_giveback_urb_bh(&hcd->high_prio_bh);
2771 	init_giveback_urb_bh(&hcd->low_prio_bh);
2772 
2773 	/* enable irqs just before we start the controller,
2774 	 * if the BIOS provides legacy PCI irqs.
2775 	 */
2776 	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2777 		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2778 		if (retval)
2779 			goto err_request_irq;
2780 	}
2781 
2782 	hcd->state = HC_STATE_RUNNING;
2783 	retval = hcd->driver->start(hcd);
2784 	if (retval < 0) {
2785 		dev_err(hcd->self.controller, "startup error %d\n", retval);
2786 		goto err_hcd_driver_start;
2787 	}
2788 
2789 	/* starting here, usbcore will pay attention to this root hub */
2790 	retval = register_root_hub(hcd);
2791 	if (retval != 0)
2792 		goto err_register_root_hub;
2793 
2794 	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2795 		usb_hcd_poll_rh_status(hcd);
2796 
2797 	return retval;
2798 
2799 err_register_root_hub:
2800 	hcd->rh_pollable = 0;
2801 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2802 	del_timer_sync(&hcd->rh_timer);
2803 	hcd->driver->stop(hcd);
2804 	hcd->state = HC_STATE_HALT;
2805 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2806 	del_timer_sync(&hcd->rh_timer);
2807 err_hcd_driver_start:
2808 	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2809 		free_irq(irqnum, hcd);
2810 err_request_irq:
2811 err_hcd_driver_setup:
2812 err_set_rh_speed:
2813 	usb_put_invalidate_rhdev(hcd);
2814 err_allocate_root_hub:
2815 	usb_deregister_bus(&hcd->self);
2816 err_register_bus:
2817 	hcd_buffer_destroy(hcd);
2818 err_create_buf:
2819 	usb_phy_roothub_power_off(hcd->phy_roothub);
2820 err_usb_phy_roothub_power_on:
2821 	usb_phy_roothub_exit(hcd->phy_roothub);
2822 
2823 	return retval;
2824 }
2825 EXPORT_SYMBOL_GPL(usb_add_hcd);
2826 
2827 /**
2828  * usb_remove_hcd - shutdown processing for generic HCDs
2829  * @hcd: the usb_hcd structure to remove
2830  * Context: !in_interrupt()
2831  *
2832  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2833  * invoking the HCD's stop() method.
2834  */
2835 void usb_remove_hcd(struct usb_hcd *hcd)
2836 {
2837 	struct usb_device *rhdev = hcd->self.root_hub;
2838 
2839 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2840 
2841 	usb_get_dev(rhdev);
2842 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2843 	if (HC_IS_RUNNING (hcd->state))
2844 		hcd->state = HC_STATE_QUIESCING;
2845 
2846 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2847 	spin_lock_irq (&hcd_root_hub_lock);
2848 	hcd->rh_registered = 0;
2849 	spin_unlock_irq (&hcd_root_hub_lock);
2850 
2851 #ifdef CONFIG_PM
2852 	cancel_work_sync(&hcd->wakeup_work);
2853 #endif
2854 	cancel_work_sync(&hcd->died_work);
2855 
2856 	mutex_lock(&usb_bus_idr_lock);
2857 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2858 	mutex_unlock(&usb_bus_idr_lock);
2859 
2860 	/*
2861 	 * tasklet_kill() isn't needed here because:
2862 	 * - driver's disconnect() called from usb_disconnect() should
2863 	 *   make sure its URBs are completed during the disconnect()
2864 	 *   callback
2865 	 *
2866 	 * - it is too late to run complete() here since driver may have
2867 	 *   been removed already now
2868 	 */
2869 
2870 	/* Prevent any more root-hub status calls from the timer.
2871 	 * The HCD might still restart the timer (if a port status change
2872 	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
2873 	 * the hub_status_data() callback.
2874 	 */
2875 	hcd->rh_pollable = 0;
2876 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2877 	del_timer_sync(&hcd->rh_timer);
2878 
2879 	hcd->driver->stop(hcd);
2880 	hcd->state = HC_STATE_HALT;
2881 
2882 	/* In case the HCD restarted the timer, stop it again. */
2883 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2884 	del_timer_sync(&hcd->rh_timer);
2885 
2886 	if (usb_hcd_is_primary_hcd(hcd)) {
2887 		if (hcd->irq > 0)
2888 			free_irq(hcd->irq, hcd);
2889 	}
2890 
2891 	usb_deregister_bus(&hcd->self);
2892 	hcd_buffer_destroy(hcd);
2893 
2894 	usb_phy_roothub_power_off(hcd->phy_roothub);
2895 	usb_phy_roothub_exit(hcd->phy_roothub);
2896 
2897 	usb_put_invalidate_rhdev(hcd);
2898 	hcd->flags = 0;
2899 }
2900 EXPORT_SYMBOL_GPL(usb_remove_hcd);
2901 
2902 void
2903 usb_hcd_platform_shutdown(struct platform_device *dev)
2904 {
2905 	struct usb_hcd *hcd = platform_get_drvdata(dev);
2906 
2907 	/* No need for pm_runtime_put(), we're shutting down */
2908 	pm_runtime_get_sync(&dev->dev);
2909 
2910 	if (hcd->driver->shutdown)
2911 		hcd->driver->shutdown(hcd);
2912 }
2913 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
2914 
2915 int usb_hcd_setup_local_mem(struct usb_hcd *hcd, phys_addr_t phys_addr,
2916 			    dma_addr_t dma, size_t size)
2917 {
2918 	int err;
2919 	void *local_mem;
2920 
2921 	hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, 4,
2922 						  dev_to_node(hcd->self.sysdev),
2923 						  dev_name(hcd->self.sysdev));
2924 	if (IS_ERR(hcd->localmem_pool))
2925 		return PTR_ERR(hcd->localmem_pool);
2926 
2927 	local_mem = devm_memremap(hcd->self.sysdev, phys_addr,
2928 				  size, MEMREMAP_WC);
2929 	if (IS_ERR(local_mem))
2930 		return PTR_ERR(local_mem);
2931 
2932 	/*
2933 	 * Here we pass a dma_addr_t but the arg type is a phys_addr_t.
2934 	 * It's not backed by system memory and thus there's no kernel mapping
2935 	 * for it.
2936 	 */
2937 	err = gen_pool_add_virt(hcd->localmem_pool, (unsigned long)local_mem,
2938 				dma, size, dev_to_node(hcd->self.sysdev));
2939 	if (err < 0) {
2940 		dev_err(hcd->self.sysdev, "gen_pool_add_virt failed with %d\n",
2941 			err);
2942 		return err;
2943 	}
2944 
2945 	return 0;
2946 }
2947 EXPORT_SYMBOL_GPL(usb_hcd_setup_local_mem);
2948 
2949 /*-------------------------------------------------------------------------*/
2950 
2951 #if IS_ENABLED(CONFIG_USB_MON)
2952 
2953 const struct usb_mon_operations *mon_ops;
2954 
2955 /*
2956  * The registration is unlocked.
2957  * We do it this way because we do not want to lock in hot paths.
2958  *
2959  * Notice that the code is minimally error-proof. Because usbmon needs
2960  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
2961  */
2962 
2963 int usb_mon_register(const struct usb_mon_operations *ops)
2964 {
2965 
2966 	if (mon_ops)
2967 		return -EBUSY;
2968 
2969 	mon_ops = ops;
2970 	mb();
2971 	return 0;
2972 }
2973 EXPORT_SYMBOL_GPL (usb_mon_register);
2974 
2975 void usb_mon_deregister (void)
2976 {
2977 
2978 	if (mon_ops == NULL) {
2979 		printk(KERN_ERR "USB: monitor was not registered\n");
2980 		return;
2981 	}
2982 	mon_ops = NULL;
2983 	mb();
2984 }
2985 EXPORT_SYMBOL_GPL (usb_mon_deregister);
2986 
2987 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
2988