xref: /openbmc/linux/drivers/usb/core/hcd.c (revision 64c70b1c)
1 /*
2  * (C) Copyright Linus Torvalds 1999
3  * (C) Copyright Johannes Erdfelt 1999-2001
4  * (C) Copyright Andreas Gal 1999
5  * (C) Copyright Gregory P. Smith 1999
6  * (C) Copyright Deti Fliegl 1999
7  * (C) Copyright Randy Dunlap 2000
8  * (C) Copyright David Brownell 2000-2002
9  *
10  * This program is free software; you can redistribute it and/or modify it
11  * under the terms of the GNU General Public License as published by the
12  * Free Software Foundation; either version 2 of the License, or (at your
13  * option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful, but
16  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
17  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
18  * for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software Foundation,
22  * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23  */
24 
25 #include <linux/module.h>
26 #include <linux/version.h>
27 #include <linux/kernel.h>
28 #include <linux/slab.h>
29 #include <linux/completion.h>
30 #include <linux/utsname.h>
31 #include <linux/mm.h>
32 #include <asm/io.h>
33 #include <asm/scatterlist.h>
34 #include <linux/device.h>
35 #include <linux/dma-mapping.h>
36 #include <linux/mutex.h>
37 #include <asm/irq.h>
38 #include <asm/byteorder.h>
39 #include <linux/platform_device.h>
40 #include <linux/workqueue.h>
41 
42 #include <linux/usb.h>
43 
44 #include "usb.h"
45 #include "hcd.h"
46 #include "hub.h"
47 
48 
49 /*-------------------------------------------------------------------------*/
50 
51 /*
52  * USB Host Controller Driver framework
53  *
54  * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
55  * HCD-specific behaviors/bugs.
56  *
57  * This does error checks, tracks devices and urbs, and delegates to a
58  * "hc_driver" only for code (and data) that really needs to know about
59  * hardware differences.  That includes root hub registers, i/o queues,
60  * and so on ... but as little else as possible.
61  *
62  * Shared code includes most of the "root hub" code (these are emulated,
63  * though each HC's hardware works differently) and PCI glue, plus request
64  * tracking overhead.  The HCD code should only block on spinlocks or on
65  * hardware handshaking; blocking on software events (such as other kernel
66  * threads releasing resources, or completing actions) is all generic.
67  *
68  * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
69  * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
70  * only by the hub driver ... and that neither should be seen or used by
71  * usb client device drivers.
72  *
73  * Contributors of ideas or unattributed patches include: David Brownell,
74  * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
75  *
76  * HISTORY:
77  * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
78  *		associated cleanup.  "usb_hcd" still != "usb_bus".
79  * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
80  */
81 
82 /*-------------------------------------------------------------------------*/
83 
84 /* host controllers we manage */
85 LIST_HEAD (usb_bus_list);
86 EXPORT_SYMBOL_GPL (usb_bus_list);
87 
88 /* used when allocating bus numbers */
89 #define USB_MAXBUS		64
90 struct usb_busmap {
91 	unsigned long busmap [USB_MAXBUS / (8*sizeof (unsigned long))];
92 };
93 static struct usb_busmap busmap;
94 
95 /* used when updating list of hcds */
96 DEFINE_MUTEX(usb_bus_list_lock);	/* exported only for usbfs */
97 EXPORT_SYMBOL_GPL (usb_bus_list_lock);
98 
99 /* used for controlling access to virtual root hubs */
100 static DEFINE_SPINLOCK(hcd_root_hub_lock);
101 
102 /* used when updating hcd data */
103 static DEFINE_SPINLOCK(hcd_data_lock);
104 
105 /* wait queue for synchronous unlinks */
106 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
107 
108 /*-------------------------------------------------------------------------*/
109 
110 /*
111  * Sharable chunks of root hub code.
112  */
113 
114 /*-------------------------------------------------------------------------*/
115 
116 #define KERNEL_REL	((LINUX_VERSION_CODE >> 16) & 0x0ff)
117 #define KERNEL_VER	((LINUX_VERSION_CODE >> 8) & 0x0ff)
118 
119 /* usb 2.0 root hub device descriptor */
120 static const u8 usb2_rh_dev_descriptor [18] = {
121 	0x12,       /*  __u8  bLength; */
122 	0x01,       /*  __u8  bDescriptorType; Device */
123 	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
124 
125 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
126 	0x00,	    /*  __u8  bDeviceSubClass; */
127 	0x01,       /*  __u8  bDeviceProtocol; [ usb 2.0 single TT ]*/
128 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
129 
130 	0x00, 0x00, /*  __le16 idVendor; */
131  	0x00, 0x00, /*  __le16 idProduct; */
132 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
133 
134 	0x03,       /*  __u8  iManufacturer; */
135 	0x02,       /*  __u8  iProduct; */
136 	0x01,       /*  __u8  iSerialNumber; */
137 	0x01        /*  __u8  bNumConfigurations; */
138 };
139 
140 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
141 
142 /* usb 1.1 root hub device descriptor */
143 static const u8 usb11_rh_dev_descriptor [18] = {
144 	0x12,       /*  __u8  bLength; */
145 	0x01,       /*  __u8  bDescriptorType; Device */
146 	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
147 
148 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
149 	0x00,	    /*  __u8  bDeviceSubClass; */
150 	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
151 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
152 
153 	0x00, 0x00, /*  __le16 idVendor; */
154  	0x00, 0x00, /*  __le16 idProduct; */
155 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
156 
157 	0x03,       /*  __u8  iManufacturer; */
158 	0x02,       /*  __u8  iProduct; */
159 	0x01,       /*  __u8  iSerialNumber; */
160 	0x01        /*  __u8  bNumConfigurations; */
161 };
162 
163 
164 /*-------------------------------------------------------------------------*/
165 
166 /* Configuration descriptors for our root hubs */
167 
168 static const u8 fs_rh_config_descriptor [] = {
169 
170 	/* one configuration */
171 	0x09,       /*  __u8  bLength; */
172 	0x02,       /*  __u8  bDescriptorType; Configuration */
173 	0x19, 0x00, /*  __le16 wTotalLength; */
174 	0x01,       /*  __u8  bNumInterfaces; (1) */
175 	0x01,       /*  __u8  bConfigurationValue; */
176 	0x00,       /*  __u8  iConfiguration; */
177 	0xc0,       /*  __u8  bmAttributes;
178 				 Bit 7: must be set,
179 				     6: Self-powered,
180 				     5: Remote wakeup,
181 				     4..0: resvd */
182 	0x00,       /*  __u8  MaxPower; */
183 
184 	/* USB 1.1:
185 	 * USB 2.0, single TT organization (mandatory):
186 	 *	one interface, protocol 0
187 	 *
188 	 * USB 2.0, multiple TT organization (optional):
189 	 *	two interfaces, protocols 1 (like single TT)
190 	 *	and 2 (multiple TT mode) ... config is
191 	 *	sometimes settable
192 	 *	NOT IMPLEMENTED
193 	 */
194 
195 	/* one interface */
196 	0x09,       /*  __u8  if_bLength; */
197 	0x04,       /*  __u8  if_bDescriptorType; Interface */
198 	0x00,       /*  __u8  if_bInterfaceNumber; */
199 	0x00,       /*  __u8  if_bAlternateSetting; */
200 	0x01,       /*  __u8  if_bNumEndpoints; */
201 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
202 	0x00,       /*  __u8  if_bInterfaceSubClass; */
203 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
204 	0x00,       /*  __u8  if_iInterface; */
205 
206 	/* one endpoint (status change endpoint) */
207 	0x07,       /*  __u8  ep_bLength; */
208 	0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
209 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
210  	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
211  	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
212 	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
213 };
214 
215 static const u8 hs_rh_config_descriptor [] = {
216 
217 	/* one configuration */
218 	0x09,       /*  __u8  bLength; */
219 	0x02,       /*  __u8  bDescriptorType; Configuration */
220 	0x19, 0x00, /*  __le16 wTotalLength; */
221 	0x01,       /*  __u8  bNumInterfaces; (1) */
222 	0x01,       /*  __u8  bConfigurationValue; */
223 	0x00,       /*  __u8  iConfiguration; */
224 	0xc0,       /*  __u8  bmAttributes;
225 				 Bit 7: must be set,
226 				     6: Self-powered,
227 				     5: Remote wakeup,
228 				     4..0: resvd */
229 	0x00,       /*  __u8  MaxPower; */
230 
231 	/* USB 1.1:
232 	 * USB 2.0, single TT organization (mandatory):
233 	 *	one interface, protocol 0
234 	 *
235 	 * USB 2.0, multiple TT organization (optional):
236 	 *	two interfaces, protocols 1 (like single TT)
237 	 *	and 2 (multiple TT mode) ... config is
238 	 *	sometimes settable
239 	 *	NOT IMPLEMENTED
240 	 */
241 
242 	/* one interface */
243 	0x09,       /*  __u8  if_bLength; */
244 	0x04,       /*  __u8  if_bDescriptorType; Interface */
245 	0x00,       /*  __u8  if_bInterfaceNumber; */
246 	0x00,       /*  __u8  if_bAlternateSetting; */
247 	0x01,       /*  __u8  if_bNumEndpoints; */
248 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
249 	0x00,       /*  __u8  if_bInterfaceSubClass; */
250 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
251 	0x00,       /*  __u8  if_iInterface; */
252 
253 	/* one endpoint (status change endpoint) */
254 	0x07,       /*  __u8  ep_bLength; */
255 	0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
256 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
257  	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
258 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
259 		     * see hub.c:hub_configure() for details. */
260 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
261 	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
262 };
263 
264 /*-------------------------------------------------------------------------*/
265 
266 /*
267  * helper routine for returning string descriptors in UTF-16LE
268  * input can actually be ISO-8859-1; ASCII is its 7-bit subset
269  */
270 static int ascii2utf (char *s, u8 *utf, int utfmax)
271 {
272 	int retval;
273 
274 	for (retval = 0; *s && utfmax > 1; utfmax -= 2, retval += 2) {
275 		*utf++ = *s++;
276 		*utf++ = 0;
277 	}
278 	if (utfmax > 0) {
279 		*utf = *s;
280 		++retval;
281 	}
282 	return retval;
283 }
284 
285 /*
286  * rh_string - provides manufacturer, product and serial strings for root hub
287  * @id: the string ID number (1: serial number, 2: product, 3: vendor)
288  * @hcd: the host controller for this root hub
289  * @type: string describing our driver
290  * @data: return packet in UTF-16 LE
291  * @len: length of the return packet
292  *
293  * Produces either a manufacturer, product or serial number string for the
294  * virtual root hub device.
295  */
296 static int rh_string (
297 	int		id,
298 	struct usb_hcd	*hcd,
299 	u8		*data,
300 	int		len
301 ) {
302 	char buf [100];
303 
304 	// language ids
305 	if (id == 0) {
306 		buf[0] = 4;    buf[1] = 3;	/* 4 bytes string data */
307 		buf[2] = 0x09; buf[3] = 0x04;	/* MSFT-speak for "en-us" */
308 		len = min (len, 4);
309 		memcpy (data, buf, len);
310 		return len;
311 
312 	// serial number
313 	} else if (id == 1) {
314 		strlcpy (buf, hcd->self.bus_name, sizeof buf);
315 
316 	// product description
317 	} else if (id == 2) {
318 		strlcpy (buf, hcd->product_desc, sizeof buf);
319 
320  	// id 3 == vendor description
321 	} else if (id == 3) {
322 		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
323 			init_utsname()->release, hcd->driver->description);
324 
325 	// unsupported IDs --> "protocol stall"
326 	} else
327 		return -EPIPE;
328 
329 	switch (len) {		/* All cases fall through */
330 	default:
331 		len = 2 + ascii2utf (buf, data + 2, len - 2);
332 	case 2:
333 		data [1] = 3;	/* type == string */
334 	case 1:
335 		data [0] = 2 * (strlen (buf) + 1);
336 	case 0:
337 		;		/* Compiler wants a statement here */
338 	}
339 	return len;
340 }
341 
342 
343 /* Root hub control transfers execute synchronously */
344 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
345 {
346 	struct usb_ctrlrequest *cmd;
347  	u16		typeReq, wValue, wIndex, wLength;
348 	u8		*ubuf = urb->transfer_buffer;
349 	u8		tbuf [sizeof (struct usb_hub_descriptor)]
350 		__attribute__((aligned(4)));
351 	const u8	*bufp = tbuf;
352 	int		len = 0;
353 	int		patch_wakeup = 0;
354 	unsigned long	flags;
355 	int		status = 0;
356 	int		n;
357 
358 	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
359 	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
360 	wValue   = le16_to_cpu (cmd->wValue);
361 	wIndex   = le16_to_cpu (cmd->wIndex);
362 	wLength  = le16_to_cpu (cmd->wLength);
363 
364 	if (wLength > urb->transfer_buffer_length)
365 		goto error;
366 
367 	urb->actual_length = 0;
368 	switch (typeReq) {
369 
370 	/* DEVICE REQUESTS */
371 
372 	/* The root hub's remote wakeup enable bit is implemented using
373 	 * driver model wakeup flags.  If this system supports wakeup
374 	 * through USB, userspace may change the default "allow wakeup"
375 	 * policy through sysfs or these calls.
376 	 *
377 	 * Most root hubs support wakeup from downstream devices, for
378 	 * runtime power management (disabling USB clocks and reducing
379 	 * VBUS power usage).  However, not all of them do so; silicon,
380 	 * board, and BIOS bugs here are not uncommon, so these can't
381 	 * be treated quite like external hubs.
382 	 *
383 	 * Likewise, not all root hubs will pass wakeup events upstream,
384 	 * to wake up the whole system.  So don't assume root hub and
385 	 * controller capabilities are identical.
386 	 */
387 
388 	case DeviceRequest | USB_REQ_GET_STATUS:
389 		tbuf [0] = (device_may_wakeup(&hcd->self.root_hub->dev)
390 					<< USB_DEVICE_REMOTE_WAKEUP)
391 				| (1 << USB_DEVICE_SELF_POWERED);
392 		tbuf [1] = 0;
393 		len = 2;
394 		break;
395 	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
396 		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
397 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
398 		else
399 			goto error;
400 		break;
401 	case DeviceOutRequest | USB_REQ_SET_FEATURE:
402 		if (device_can_wakeup(&hcd->self.root_hub->dev)
403 				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
404 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
405 		else
406 			goto error;
407 		break;
408 	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
409 		tbuf [0] = 1;
410 		len = 1;
411 			/* FALLTHROUGH */
412 	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
413 		break;
414 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
415 		switch (wValue & 0xff00) {
416 		case USB_DT_DEVICE << 8:
417 			if (hcd->driver->flags & HCD_USB2)
418 				bufp = usb2_rh_dev_descriptor;
419 			else if (hcd->driver->flags & HCD_USB11)
420 				bufp = usb11_rh_dev_descriptor;
421 			else
422 				goto error;
423 			len = 18;
424 			break;
425 		case USB_DT_CONFIG << 8:
426 			if (hcd->driver->flags & HCD_USB2) {
427 				bufp = hs_rh_config_descriptor;
428 				len = sizeof hs_rh_config_descriptor;
429 			} else {
430 				bufp = fs_rh_config_descriptor;
431 				len = sizeof fs_rh_config_descriptor;
432 			}
433 			if (device_can_wakeup(&hcd->self.root_hub->dev))
434 				patch_wakeup = 1;
435 			break;
436 		case USB_DT_STRING << 8:
437 			n = rh_string (wValue & 0xff, hcd, ubuf, wLength);
438 			if (n < 0)
439 				goto error;
440 			urb->actual_length = n;
441 			break;
442 		default:
443 			goto error;
444 		}
445 		break;
446 	case DeviceRequest | USB_REQ_GET_INTERFACE:
447 		tbuf [0] = 0;
448 		len = 1;
449 			/* FALLTHROUGH */
450 	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
451 		break;
452 	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
453 		// wValue == urb->dev->devaddr
454 		dev_dbg (hcd->self.controller, "root hub device address %d\n",
455 			wValue);
456 		break;
457 
458 	/* INTERFACE REQUESTS (no defined feature/status flags) */
459 
460 	/* ENDPOINT REQUESTS */
461 
462 	case EndpointRequest | USB_REQ_GET_STATUS:
463 		// ENDPOINT_HALT flag
464 		tbuf [0] = 0;
465 		tbuf [1] = 0;
466 		len = 2;
467 			/* FALLTHROUGH */
468 	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
469 	case EndpointOutRequest | USB_REQ_SET_FEATURE:
470 		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
471 		break;
472 
473 	/* CLASS REQUESTS (and errors) */
474 
475 	default:
476 		/* non-generic request */
477 		switch (typeReq) {
478 		case GetHubStatus:
479 		case GetPortStatus:
480 			len = 4;
481 			break;
482 		case GetHubDescriptor:
483 			len = sizeof (struct usb_hub_descriptor);
484 			break;
485 		}
486 		status = hcd->driver->hub_control (hcd,
487 			typeReq, wValue, wIndex,
488 			tbuf, wLength);
489 		break;
490 error:
491 		/* "protocol stall" on error */
492 		status = -EPIPE;
493 	}
494 
495 	if (status) {
496 		len = 0;
497 		if (status != -EPIPE) {
498 			dev_dbg (hcd->self.controller,
499 				"CTRL: TypeReq=0x%x val=0x%x "
500 				"idx=0x%x len=%d ==> %d\n",
501 				typeReq, wValue, wIndex,
502 				wLength, status);
503 		}
504 	}
505 	if (len) {
506 		if (urb->transfer_buffer_length < len)
507 			len = urb->transfer_buffer_length;
508 		urb->actual_length = len;
509 		// always USB_DIR_IN, toward host
510 		memcpy (ubuf, bufp, len);
511 
512 		/* report whether RH hardware supports remote wakeup */
513 		if (patch_wakeup &&
514 				len > offsetof (struct usb_config_descriptor,
515 						bmAttributes))
516 			((struct usb_config_descriptor *)ubuf)->bmAttributes
517 				|= USB_CONFIG_ATT_WAKEUP;
518 	}
519 
520 	/* any errors get returned through the urb completion */
521 	local_irq_save (flags);
522 	spin_lock (&urb->lock);
523 	if (urb->status == -EINPROGRESS)
524 		urb->status = status;
525 	spin_unlock (&urb->lock);
526 	usb_hcd_giveback_urb (hcd, urb);
527 	local_irq_restore (flags);
528 	return 0;
529 }
530 
531 /*-------------------------------------------------------------------------*/
532 
533 /*
534  * Root Hub interrupt transfers are polled using a timer if the
535  * driver requests it; otherwise the driver is responsible for
536  * calling usb_hcd_poll_rh_status() when an event occurs.
537  *
538  * Completions are called in_interrupt(), but they may or may not
539  * be in_irq().
540  */
541 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
542 {
543 	struct urb	*urb;
544 	int		length;
545 	unsigned long	flags;
546 	char		buffer[4];	/* Any root hubs with > 31 ports? */
547 
548 	if (unlikely(!hcd->rh_registered))
549 		return;
550 	if (!hcd->uses_new_polling && !hcd->status_urb)
551 		return;
552 
553 	length = hcd->driver->hub_status_data(hcd, buffer);
554 	if (length > 0) {
555 
556 		/* try to complete the status urb */
557 		local_irq_save (flags);
558 		spin_lock(&hcd_root_hub_lock);
559 		urb = hcd->status_urb;
560 		if (urb) {
561 			spin_lock(&urb->lock);
562 			if (urb->status == -EINPROGRESS) {
563 				hcd->poll_pending = 0;
564 				hcd->status_urb = NULL;
565 				urb->status = 0;
566 				urb->hcpriv = NULL;
567 				urb->actual_length = length;
568 				memcpy(urb->transfer_buffer, buffer, length);
569 			} else		/* urb has been unlinked */
570 				length = 0;
571 			spin_unlock(&urb->lock);
572 		} else
573 			length = 0;
574 		spin_unlock(&hcd_root_hub_lock);
575 
576 		/* local irqs are always blocked in completions */
577 		if (length > 0)
578 			usb_hcd_giveback_urb (hcd, urb);
579 		else
580 			hcd->poll_pending = 1;
581 		local_irq_restore (flags);
582 	}
583 
584 	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
585 	 * exceed that limit if HZ is 100. */
586 	if (hcd->uses_new_polling ? hcd->poll_rh :
587 			(length == 0 && hcd->status_urb != NULL))
588 		mod_timer (&hcd->rh_timer, jiffies + msecs_to_jiffies(250));
589 }
590 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
591 
592 /* timer callback */
593 static void rh_timer_func (unsigned long _hcd)
594 {
595 	usb_hcd_poll_rh_status((struct usb_hcd *) _hcd);
596 }
597 
598 /*-------------------------------------------------------------------------*/
599 
600 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
601 {
602 	int		retval;
603 	unsigned long	flags;
604 	int		len = 1 + (urb->dev->maxchild / 8);
605 
606 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
607 	if (urb->status != -EINPROGRESS)	/* already unlinked */
608 		retval = urb->status;
609 	else if (hcd->status_urb || urb->transfer_buffer_length < len) {
610 		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
611 		retval = -EINVAL;
612 	} else {
613 		hcd->status_urb = urb;
614 		urb->hcpriv = hcd;	/* indicate it's queued */
615 
616 		if (!hcd->uses_new_polling)
617 			mod_timer (&hcd->rh_timer, jiffies +
618 					msecs_to_jiffies(250));
619 
620 		/* If a status change has already occurred, report it ASAP */
621 		else if (hcd->poll_pending)
622 			mod_timer (&hcd->rh_timer, jiffies);
623 		retval = 0;
624 	}
625 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
626 	return retval;
627 }
628 
629 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
630 {
631 	if (usb_pipeint (urb->pipe))
632 		return rh_queue_status (hcd, urb);
633 	if (usb_pipecontrol (urb->pipe))
634 		return rh_call_control (hcd, urb);
635 	return -EINVAL;
636 }
637 
638 /*-------------------------------------------------------------------------*/
639 
640 /* Unlinks of root-hub control URBs are legal, but they don't do anything
641  * since these URBs always execute synchronously.
642  */
643 static int usb_rh_urb_dequeue (struct usb_hcd *hcd, struct urb *urb)
644 {
645 	unsigned long	flags;
646 
647 	if (usb_pipeendpoint(urb->pipe) == 0) {	/* Control URB */
648 		;	/* Do nothing */
649 
650 	} else {				/* Status URB */
651 		if (!hcd->uses_new_polling)
652 			del_timer (&hcd->rh_timer);
653 		local_irq_save (flags);
654 		spin_lock (&hcd_root_hub_lock);
655 		if (urb == hcd->status_urb) {
656 			hcd->status_urb = NULL;
657 			urb->hcpriv = NULL;
658 		} else
659 			urb = NULL;		/* wasn't fully queued */
660 		spin_unlock (&hcd_root_hub_lock);
661 		if (urb)
662 			usb_hcd_giveback_urb (hcd, urb);
663 		local_irq_restore (flags);
664 	}
665 
666 	return 0;
667 }
668 
669 /*-------------------------------------------------------------------------*/
670 
671 static struct class *usb_host_class;
672 
673 int usb_host_init(void)
674 {
675 	int retval = 0;
676 
677 	usb_host_class = class_create(THIS_MODULE, "usb_host");
678 	if (IS_ERR(usb_host_class))
679 		retval = PTR_ERR(usb_host_class);
680 	return retval;
681 }
682 
683 void usb_host_cleanup(void)
684 {
685 	class_destroy(usb_host_class);
686 }
687 
688 /**
689  * usb_bus_init - shared initialization code
690  * @bus: the bus structure being initialized
691  *
692  * This code is used to initialize a usb_bus structure, memory for which is
693  * separately managed.
694  */
695 static void usb_bus_init (struct usb_bus *bus)
696 {
697 	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
698 
699 	bus->devnum_next = 1;
700 
701 	bus->root_hub = NULL;
702 	bus->busnum = -1;
703 	bus->bandwidth_allocated = 0;
704 	bus->bandwidth_int_reqs  = 0;
705 	bus->bandwidth_isoc_reqs = 0;
706 
707 	INIT_LIST_HEAD (&bus->bus_list);
708 }
709 
710 /*-------------------------------------------------------------------------*/
711 
712 /**
713  * usb_register_bus - registers the USB host controller with the usb core
714  * @bus: pointer to the bus to register
715  * Context: !in_interrupt()
716  *
717  * Assigns a bus number, and links the controller into usbcore data
718  * structures so that it can be seen by scanning the bus list.
719  */
720 static int usb_register_bus(struct usb_bus *bus)
721 {
722 	int busnum;
723 
724 	mutex_lock(&usb_bus_list_lock);
725 	busnum = find_next_zero_bit (busmap.busmap, USB_MAXBUS, 1);
726 	if (busnum < USB_MAXBUS) {
727 		set_bit (busnum, busmap.busmap);
728 		bus->busnum = busnum;
729 	} else {
730 		printk (KERN_ERR "%s: too many buses\n", usbcore_name);
731 		mutex_unlock(&usb_bus_list_lock);
732 		return -E2BIG;
733 	}
734 
735 	bus->class_dev = class_device_create(usb_host_class, NULL, MKDEV(0,0),
736 					     bus->controller, "usb_host%d", busnum);
737 	if (IS_ERR(bus->class_dev)) {
738 		clear_bit(busnum, busmap.busmap);
739 		mutex_unlock(&usb_bus_list_lock);
740 		return PTR_ERR(bus->class_dev);
741 	}
742 
743 	class_set_devdata(bus->class_dev, bus);
744 
745 	/* Add it to the local list of buses */
746 	list_add (&bus->bus_list, &usb_bus_list);
747 	mutex_unlock(&usb_bus_list_lock);
748 
749 	usb_notify_add_bus(bus);
750 
751 	dev_info (bus->controller, "new USB bus registered, assigned bus number %d\n", bus->busnum);
752 	return 0;
753 }
754 
755 /**
756  * usb_deregister_bus - deregisters the USB host controller
757  * @bus: pointer to the bus to deregister
758  * Context: !in_interrupt()
759  *
760  * Recycles the bus number, and unlinks the controller from usbcore data
761  * structures so that it won't be seen by scanning the bus list.
762  */
763 static void usb_deregister_bus (struct usb_bus *bus)
764 {
765 	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
766 
767 	/*
768 	 * NOTE: make sure that all the devices are removed by the
769 	 * controller code, as well as having it call this when cleaning
770 	 * itself up
771 	 */
772 	mutex_lock(&usb_bus_list_lock);
773 	list_del (&bus->bus_list);
774 	mutex_unlock(&usb_bus_list_lock);
775 
776 	usb_notify_remove_bus(bus);
777 
778 	clear_bit (bus->busnum, busmap.busmap);
779 
780 	class_device_unregister(bus->class_dev);
781 }
782 
783 /**
784  * register_root_hub - called by usb_add_hcd() to register a root hub
785  * @hcd: host controller for this root hub
786  *
787  * This function registers the root hub with the USB subsystem.  It sets up
788  * the device properly in the device tree and then calls usb_new_device()
789  * to register the usb device.  It also assigns the root hub's USB address
790  * (always 1).
791  */
792 static int register_root_hub(struct usb_hcd *hcd)
793 {
794 	struct device *parent_dev = hcd->self.controller;
795 	struct usb_device *usb_dev = hcd->self.root_hub;
796 	const int devnum = 1;
797 	int retval;
798 
799 	usb_dev->devnum = devnum;
800 	usb_dev->bus->devnum_next = devnum + 1;
801 	memset (&usb_dev->bus->devmap.devicemap, 0,
802 			sizeof usb_dev->bus->devmap.devicemap);
803 	set_bit (devnum, usb_dev->bus->devmap.devicemap);
804 	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
805 
806 	mutex_lock(&usb_bus_list_lock);
807 
808 	usb_dev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
809 	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
810 	if (retval != sizeof usb_dev->descriptor) {
811 		mutex_unlock(&usb_bus_list_lock);
812 		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
813 				usb_dev->dev.bus_id, retval);
814 		return (retval < 0) ? retval : -EMSGSIZE;
815 	}
816 
817 	retval = usb_new_device (usb_dev);
818 	if (retval) {
819 		dev_err (parent_dev, "can't register root hub for %s, %d\n",
820 				usb_dev->dev.bus_id, retval);
821 	}
822 	mutex_unlock(&usb_bus_list_lock);
823 
824 	if (retval == 0) {
825 		spin_lock_irq (&hcd_root_hub_lock);
826 		hcd->rh_registered = 1;
827 		spin_unlock_irq (&hcd_root_hub_lock);
828 
829 		/* Did the HC die before the root hub was registered? */
830 		if (hcd->state == HC_STATE_HALT)
831 			usb_hc_died (hcd);	/* This time clean up */
832 	}
833 
834 	return retval;
835 }
836 
837 void usb_enable_root_hub_irq (struct usb_bus *bus)
838 {
839 	struct usb_hcd *hcd;
840 
841 	hcd = container_of (bus, struct usb_hcd, self);
842 	if (hcd->driver->hub_irq_enable && hcd->state != HC_STATE_HALT)
843 		hcd->driver->hub_irq_enable (hcd);
844 }
845 
846 
847 /*-------------------------------------------------------------------------*/
848 
849 /**
850  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
851  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
852  * @is_input: true iff the transaction sends data to the host
853  * @isoc: true for isochronous transactions, false for interrupt ones
854  * @bytecount: how many bytes in the transaction.
855  *
856  * Returns approximate bus time in nanoseconds for a periodic transaction.
857  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
858  * scheduled in software, this function is only used for such scheduling.
859  */
860 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
861 {
862 	unsigned long	tmp;
863 
864 	switch (speed) {
865 	case USB_SPEED_LOW: 	/* INTR only */
866 		if (is_input) {
867 			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
868 			return (64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp);
869 		} else {
870 			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
871 			return (64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp);
872 		}
873 	case USB_SPEED_FULL:	/* ISOC or INTR */
874 		if (isoc) {
875 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
876 			return (((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp);
877 		} else {
878 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
879 			return (9107L + BW_HOST_DELAY + tmp);
880 		}
881 	case USB_SPEED_HIGH:	/* ISOC or INTR */
882 		// FIXME adjust for input vs output
883 		if (isoc)
884 			tmp = HS_NSECS_ISO (bytecount);
885 		else
886 			tmp = HS_NSECS (bytecount);
887 		return tmp;
888 	default:
889 		pr_debug ("%s: bogus device speed!\n", usbcore_name);
890 		return -1;
891 	}
892 }
893 EXPORT_SYMBOL (usb_calc_bus_time);
894 
895 
896 /*-------------------------------------------------------------------------*/
897 
898 /*
899  * Generic HC operations.
900  */
901 
902 /*-------------------------------------------------------------------------*/
903 
904 static void urb_unlink (struct urb *urb)
905 {
906 	unsigned long		flags;
907 
908 	/* clear all state linking urb to this dev (and hcd) */
909 
910 	spin_lock_irqsave (&hcd_data_lock, flags);
911 	list_del_init (&urb->urb_list);
912 	spin_unlock_irqrestore (&hcd_data_lock, flags);
913 }
914 
915 
916 /* may be called in any context with a valid urb->dev usecount
917  * caller surrenders "ownership" of urb
918  * expects usb_submit_urb() to have sanity checked and conditioned all
919  * inputs in the urb
920  */
921 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
922 {
923 	int			status;
924 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
925 	struct usb_host_endpoint *ep;
926 	unsigned long		flags;
927 
928 	if (!hcd)
929 		return -ENODEV;
930 
931 	usbmon_urb_submit(&hcd->self, urb);
932 
933 	/*
934 	 * Atomically queue the urb,  first to our records, then to the HCD.
935 	 * Access to urb->status is controlled by urb->lock ... changes on
936 	 * i/o completion (normal or fault) or unlinking.
937 	 */
938 
939 	// FIXME:  verify that quiescing hc works right (RH cleans up)
940 
941 	spin_lock_irqsave (&hcd_data_lock, flags);
942 	ep = (usb_pipein(urb->pipe) ? urb->dev->ep_in : urb->dev->ep_out)
943 			[usb_pipeendpoint(urb->pipe)];
944 	if (unlikely (!ep))
945 		status = -ENOENT;
946 	else if (unlikely (urb->reject))
947 		status = -EPERM;
948 	else switch (hcd->state) {
949 	case HC_STATE_RUNNING:
950 	case HC_STATE_RESUMING:
951 doit:
952 		list_add_tail (&urb->urb_list, &ep->urb_list);
953 		status = 0;
954 		break;
955 	case HC_STATE_SUSPENDED:
956 		/* HC upstream links (register access, wakeup signaling) can work
957 		 * even when the downstream links (and DMA etc) are quiesced; let
958 		 * usbcore talk to the root hub.
959 		 */
960 		if (hcd->self.controller->power.power_state.event == PM_EVENT_ON
961 				&& urb->dev->parent == NULL)
962 			goto doit;
963 		/* FALL THROUGH */
964 	default:
965 		status = -ESHUTDOWN;
966 		break;
967 	}
968 	spin_unlock_irqrestore (&hcd_data_lock, flags);
969 	if (status) {
970 		INIT_LIST_HEAD (&urb->urb_list);
971 		usbmon_urb_submit_error(&hcd->self, urb, status);
972 		return status;
973 	}
974 
975 	/* increment urb's reference count as part of giving it to the HCD
976 	 * (which now controls it).  HCD guarantees that it either returns
977 	 * an error or calls giveback(), but not both.
978 	 */
979 	urb = usb_get_urb (urb);
980 	atomic_inc (&urb->use_count);
981 
982 	if (urb->dev == hcd->self.root_hub) {
983 		/* NOTE:  requirement on hub callers (usbfs and the hub
984 		 * driver, for now) that URBs' urb->transfer_buffer be
985 		 * valid and usb_buffer_{sync,unmap}() not be needed, since
986 		 * they could clobber root hub response data.
987 		 */
988 		status = rh_urb_enqueue (hcd, urb);
989 		goto done;
990 	}
991 
992 	/* lower level hcd code should use *_dma exclusively,
993 	 * unless it uses pio or talks to another transport.
994 	 */
995 	if (hcd->self.uses_dma) {
996 		if (usb_pipecontrol (urb->pipe)
997 			&& !(urb->transfer_flags & URB_NO_SETUP_DMA_MAP))
998 			urb->setup_dma = dma_map_single (
999 					hcd->self.controller,
1000 					urb->setup_packet,
1001 					sizeof (struct usb_ctrlrequest),
1002 					DMA_TO_DEVICE);
1003 		if (urb->transfer_buffer_length != 0
1004 			&& !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP))
1005 			urb->transfer_dma = dma_map_single (
1006 					hcd->self.controller,
1007 					urb->transfer_buffer,
1008 					urb->transfer_buffer_length,
1009 					usb_pipein (urb->pipe)
1010 					    ? DMA_FROM_DEVICE
1011 					    : DMA_TO_DEVICE);
1012 	}
1013 
1014 	status = hcd->driver->urb_enqueue (hcd, ep, urb, mem_flags);
1015 done:
1016 	if (unlikely (status)) {
1017 		urb_unlink (urb);
1018 		atomic_dec (&urb->use_count);
1019 		if (urb->reject)
1020 			wake_up (&usb_kill_urb_queue);
1021 		usbmon_urb_submit_error(&hcd->self, urb, status);
1022 		usb_put_urb (urb);
1023 	}
1024 	return status;
1025 }
1026 
1027 /*-------------------------------------------------------------------------*/
1028 
1029 /* called in any context */
1030 int usb_hcd_get_frame_number (struct usb_device *udev)
1031 {
1032 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
1033 
1034 	if (!HC_IS_RUNNING (hcd->state))
1035 		return -ESHUTDOWN;
1036 	return hcd->driver->get_frame_number (hcd);
1037 }
1038 
1039 /*-------------------------------------------------------------------------*/
1040 
1041 /* this makes the hcd giveback() the urb more quickly, by kicking it
1042  * off hardware queues (which may take a while) and returning it as
1043  * soon as practical.  we've already set up the urb's return status,
1044  * but we can't know if the callback completed already.
1045  */
1046 static int
1047 unlink1 (struct usb_hcd *hcd, struct urb *urb)
1048 {
1049 	int		value;
1050 
1051 	if (urb->dev == hcd->self.root_hub)
1052 		value = usb_rh_urb_dequeue (hcd, urb);
1053 	else {
1054 
1055 		/* The only reason an HCD might fail this call is if
1056 		 * it has not yet fully queued the urb to begin with.
1057 		 * Such failures should be harmless. */
1058 		value = hcd->driver->urb_dequeue (hcd, urb);
1059 	}
1060 
1061 	if (value != 0)
1062 		dev_dbg (hcd->self.controller, "dequeue %p --> %d\n",
1063 				urb, value);
1064 	return value;
1065 }
1066 
1067 /*
1068  * called in any context
1069  *
1070  * caller guarantees urb won't be recycled till both unlink()
1071  * and the urb's completion function return
1072  */
1073 int usb_hcd_unlink_urb (struct urb *urb, int status)
1074 {
1075 	struct usb_host_endpoint	*ep;
1076 	struct usb_hcd			*hcd = NULL;
1077 	struct device			*sys = NULL;
1078 	unsigned long			flags;
1079 	struct list_head		*tmp;
1080 	int				retval;
1081 
1082 	if (!urb)
1083 		return -EINVAL;
1084 	if (!urb->dev || !urb->dev->bus)
1085 		return -ENODEV;
1086 	ep = (usb_pipein(urb->pipe) ? urb->dev->ep_in : urb->dev->ep_out)
1087 			[usb_pipeendpoint(urb->pipe)];
1088 	if (!ep)
1089 		return -ENODEV;
1090 
1091 	/*
1092 	 * we contend for urb->status with the hcd core,
1093 	 * which changes it while returning the urb.
1094 	 *
1095 	 * Caller guaranteed that the urb pointer hasn't been freed, and
1096 	 * that it was submitted.  But as a rule it can't know whether or
1097 	 * not it's already been unlinked ... so we respect the reversed
1098 	 * lock sequence needed for the usb_hcd_giveback_urb() code paths
1099 	 * (urb lock, then hcd_data_lock) in case some other CPU is now
1100 	 * unlinking it.
1101 	 */
1102 	spin_lock_irqsave (&urb->lock, flags);
1103 	spin_lock (&hcd_data_lock);
1104 
1105 	sys = &urb->dev->dev;
1106 	hcd = bus_to_hcd(urb->dev->bus);
1107 	if (hcd == NULL) {
1108 		retval = -ENODEV;
1109 		goto done;
1110 	}
1111 
1112 	/* insist the urb is still queued */
1113 	list_for_each(tmp, &ep->urb_list) {
1114 		if (tmp == &urb->urb_list)
1115 			break;
1116 	}
1117 	if (tmp != &urb->urb_list) {
1118 		retval = -EIDRM;
1119 		goto done;
1120 	}
1121 
1122 	/* Any status except -EINPROGRESS means something already started to
1123 	 * unlink this URB from the hardware.  So there's no more work to do.
1124 	 */
1125 	if (urb->status != -EINPROGRESS) {
1126 		retval = -EBUSY;
1127 		goto done;
1128 	}
1129 
1130 	/* IRQ setup can easily be broken so that USB controllers
1131 	 * never get completion IRQs ... maybe even the ones we need to
1132 	 * finish unlinking the initial failed usb_set_address()
1133 	 * or device descriptor fetch.
1134 	 */
1135 	if (!test_bit(HCD_FLAG_SAW_IRQ, &hcd->flags)
1136 	    && hcd->self.root_hub != urb->dev) {
1137 		dev_warn (hcd->self.controller, "Unlink after no-IRQ?  "
1138 			"Controller is probably using the wrong IRQ."
1139 			"\n");
1140 		set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
1141 	}
1142 
1143 	urb->status = status;
1144 
1145 	spin_unlock (&hcd_data_lock);
1146 	spin_unlock_irqrestore (&urb->lock, flags);
1147 
1148 	retval = unlink1 (hcd, urb);
1149 	if (retval == 0)
1150 		retval = -EINPROGRESS;
1151 	return retval;
1152 
1153 done:
1154 	spin_unlock (&hcd_data_lock);
1155 	spin_unlock_irqrestore (&urb->lock, flags);
1156 	if (retval != -EIDRM && sys && sys->driver)
1157 		dev_dbg (sys, "hcd_unlink_urb %p fail %d\n", urb, retval);
1158 	return retval;
1159 }
1160 
1161 /*-------------------------------------------------------------------------*/
1162 
1163 /* disables the endpoint: cancels any pending urbs, then synchronizes with
1164  * the hcd to make sure all endpoint state is gone from hardware, and then
1165  * waits until the endpoint's queue is completely drained. use for
1166  * set_configuration, set_interface, driver removal, physical disconnect.
1167  *
1168  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
1169  * type, maxpacket size, toggle, halt status, and scheduling.
1170  */
1171 void usb_hcd_endpoint_disable (struct usb_device *udev,
1172 		struct usb_host_endpoint *ep)
1173 {
1174 	struct usb_hcd		*hcd;
1175 	struct urb		*urb;
1176 
1177 	hcd = bus_to_hcd(udev->bus);
1178 	local_irq_disable ();
1179 
1180 	/* ep is already gone from udev->ep_{in,out}[]; no more submits */
1181 rescan:
1182 	spin_lock (&hcd_data_lock);
1183 	list_for_each_entry (urb, &ep->urb_list, urb_list) {
1184 		int	tmp;
1185 
1186 		/* the urb may already have been unlinked */
1187 		if (urb->status != -EINPROGRESS)
1188 			continue;
1189 		usb_get_urb (urb);
1190 		spin_unlock (&hcd_data_lock);
1191 
1192 		spin_lock (&urb->lock);
1193 		tmp = urb->status;
1194 		if (tmp == -EINPROGRESS)
1195 			urb->status = -ESHUTDOWN;
1196 		spin_unlock (&urb->lock);
1197 
1198 		/* kick hcd unless it's already returning this */
1199 		if (tmp == -EINPROGRESS) {
1200 			tmp = urb->pipe;
1201 			unlink1 (hcd, urb);
1202 			dev_dbg (hcd->self.controller,
1203 				"shutdown urb %p pipe %08x ep%d%s%s\n",
1204 				urb, tmp, usb_pipeendpoint (tmp),
1205 				(tmp & USB_DIR_IN) ? "in" : "out",
1206 				({ char *s; \
1207 				 switch (usb_pipetype (tmp)) { \
1208 				 case PIPE_CONTROL:	s = ""; break; \
1209 				 case PIPE_BULK:	s = "-bulk"; break; \
1210 				 case PIPE_INTERRUPT:	s = "-intr"; break; \
1211 				 default: 		s = "-iso"; break; \
1212 				}; s;}));
1213 		}
1214 		usb_put_urb (urb);
1215 
1216 		/* list contents may have changed */
1217 		goto rescan;
1218 	}
1219 	spin_unlock (&hcd_data_lock);
1220 	local_irq_enable ();
1221 
1222 	/* synchronize with the hardware, so old configuration state
1223 	 * clears out immediately (and will be freed).
1224 	 */
1225 	might_sleep ();
1226 	if (hcd->driver->endpoint_disable)
1227 		hcd->driver->endpoint_disable (hcd, ep);
1228 
1229 	/* Wait until the endpoint queue is completely empty.  Most HCDs
1230 	 * will have done this already in their endpoint_disable method,
1231 	 * but some might not.  And there could be root-hub control URBs
1232 	 * still pending since they aren't affected by the HCDs'
1233 	 * endpoint_disable methods.
1234 	 */
1235 	while (!list_empty (&ep->urb_list)) {
1236 		spin_lock_irq (&hcd_data_lock);
1237 
1238 		/* The list may have changed while we acquired the spinlock */
1239 		urb = NULL;
1240 		if (!list_empty (&ep->urb_list)) {
1241 			urb = list_entry (ep->urb_list.prev, struct urb,
1242 					urb_list);
1243 			usb_get_urb (urb);
1244 		}
1245 		spin_unlock_irq (&hcd_data_lock);
1246 
1247 		if (urb) {
1248 			usb_kill_urb (urb);
1249 			usb_put_urb (urb);
1250 		}
1251 	}
1252 }
1253 
1254 /*-------------------------------------------------------------------------*/
1255 
1256 #ifdef	CONFIG_PM
1257 
1258 int hcd_bus_suspend (struct usb_bus *bus)
1259 {
1260 	struct usb_hcd		*hcd;
1261 	int			status;
1262 
1263 	hcd = container_of (bus, struct usb_hcd, self);
1264 	if (!hcd->driver->bus_suspend)
1265 		return -ENOENT;
1266 	hcd->state = HC_STATE_QUIESCING;
1267 	status = hcd->driver->bus_suspend (hcd);
1268 	if (status == 0)
1269 		hcd->state = HC_STATE_SUSPENDED;
1270 	else
1271 		dev_dbg(&bus->root_hub->dev, "%s fail, err %d\n",
1272 				"suspend", status);
1273 	return status;
1274 }
1275 
1276 int hcd_bus_resume (struct usb_bus *bus)
1277 {
1278 	struct usb_hcd		*hcd;
1279 	int			status;
1280 
1281 	hcd = container_of (bus, struct usb_hcd, self);
1282 	if (!hcd->driver->bus_resume)
1283 		return -ENOENT;
1284 	if (hcd->state == HC_STATE_RUNNING)
1285 		return 0;
1286 	hcd->state = HC_STATE_RESUMING;
1287 	status = hcd->driver->bus_resume (hcd);
1288 	if (status == 0)
1289 		hcd->state = HC_STATE_RUNNING;
1290 	else {
1291 		dev_dbg(&bus->root_hub->dev, "%s fail, err %d\n",
1292 				"resume", status);
1293 		usb_hc_died(hcd);
1294 	}
1295 	return status;
1296 }
1297 
1298 /* Workqueue routine for root-hub remote wakeup */
1299 static void hcd_resume_work(struct work_struct *work)
1300 {
1301 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
1302 	struct usb_device *udev = hcd->self.root_hub;
1303 
1304 	usb_lock_device(udev);
1305 	usb_mark_last_busy(udev);
1306 	usb_external_resume_device(udev);
1307 	usb_unlock_device(udev);
1308 }
1309 
1310 /**
1311  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
1312  * @hcd: host controller for this root hub
1313  *
1314  * The USB host controller calls this function when its root hub is
1315  * suspended (with the remote wakeup feature enabled) and a remote
1316  * wakeup request is received.  The routine submits a workqueue request
1317  * to resume the root hub (that is, manage its downstream ports again).
1318  */
1319 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
1320 {
1321 	unsigned long flags;
1322 
1323 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
1324 	if (hcd->rh_registered)
1325 		queue_work(ksuspend_usb_wq, &hcd->wakeup_work);
1326 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
1327 }
1328 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
1329 
1330 #endif
1331 
1332 /*-------------------------------------------------------------------------*/
1333 
1334 #ifdef	CONFIG_USB_OTG
1335 
1336 /**
1337  * usb_bus_start_enum - start immediate enumeration (for OTG)
1338  * @bus: the bus (must use hcd framework)
1339  * @port_num: 1-based number of port; usually bus->otg_port
1340  * Context: in_interrupt()
1341  *
1342  * Starts enumeration, with an immediate reset followed later by
1343  * khubd identifying and possibly configuring the device.
1344  * This is needed by OTG controller drivers, where it helps meet
1345  * HNP protocol timing requirements for starting a port reset.
1346  */
1347 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
1348 {
1349 	struct usb_hcd		*hcd;
1350 	int			status = -EOPNOTSUPP;
1351 
1352 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
1353 	 * boards with root hubs hooked up to internal devices (instead of
1354 	 * just the OTG port) may need more attention to resetting...
1355 	 */
1356 	hcd = container_of (bus, struct usb_hcd, self);
1357 	if (port_num && hcd->driver->start_port_reset)
1358 		status = hcd->driver->start_port_reset(hcd, port_num);
1359 
1360 	/* run khubd shortly after (first) root port reset finishes;
1361 	 * it may issue others, until at least 50 msecs have passed.
1362 	 */
1363 	if (status == 0)
1364 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
1365 	return status;
1366 }
1367 EXPORT_SYMBOL (usb_bus_start_enum);
1368 
1369 #endif
1370 
1371 /*-------------------------------------------------------------------------*/
1372 
1373 /**
1374  * usb_hcd_giveback_urb - return URB from HCD to device driver
1375  * @hcd: host controller returning the URB
1376  * @urb: urb being returned to the USB device driver.
1377  * Context: in_interrupt()
1378  *
1379  * This hands the URB from HCD to its USB device driver, using its
1380  * completion function.  The HCD has freed all per-urb resources
1381  * (and is done using urb->hcpriv).  It also released all HCD locks;
1382  * the device driver won't cause problems if it frees, modifies,
1383  * or resubmits this URB.
1384  */
1385 void usb_hcd_giveback_urb (struct usb_hcd *hcd, struct urb *urb)
1386 {
1387 	int at_root_hub;
1388 
1389 	at_root_hub = (urb->dev == hcd->self.root_hub);
1390 	urb_unlink (urb);
1391 
1392 	/* lower level hcd code should use *_dma exclusively if the
1393 	 * host controller does DMA */
1394 	if (hcd->self.uses_dma && !at_root_hub) {
1395 		if (usb_pipecontrol (urb->pipe)
1396 			&& !(urb->transfer_flags & URB_NO_SETUP_DMA_MAP))
1397 			dma_unmap_single (hcd->self.controller, urb->setup_dma,
1398 					sizeof (struct usb_ctrlrequest),
1399 					DMA_TO_DEVICE);
1400 		if (urb->transfer_buffer_length != 0
1401 			&& !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP))
1402 			dma_unmap_single (hcd->self.controller,
1403 					urb->transfer_dma,
1404 					urb->transfer_buffer_length,
1405 					usb_pipein (urb->pipe)
1406 					    ? DMA_FROM_DEVICE
1407 					    : DMA_TO_DEVICE);
1408 	}
1409 
1410 	usbmon_urb_complete (&hcd->self, urb);
1411 	/* pass ownership to the completion handler */
1412 	urb->complete (urb);
1413 	atomic_dec (&urb->use_count);
1414 	if (unlikely (urb->reject))
1415 		wake_up (&usb_kill_urb_queue);
1416 	usb_put_urb (urb);
1417 }
1418 EXPORT_SYMBOL (usb_hcd_giveback_urb);
1419 
1420 /*-------------------------------------------------------------------------*/
1421 
1422 /**
1423  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
1424  * @irq: the IRQ being raised
1425  * @__hcd: pointer to the HCD whose IRQ is being signaled
1426  * @r: saved hardware registers
1427  *
1428  * If the controller isn't HALTed, calls the driver's irq handler.
1429  * Checks whether the controller is now dead.
1430  */
1431 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
1432 {
1433 	struct usb_hcd		*hcd = __hcd;
1434 	int			start = hcd->state;
1435 
1436 	if (unlikely(start == HC_STATE_HALT ||
1437 	    !test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)))
1438 		return IRQ_NONE;
1439 	if (hcd->driver->irq (hcd) == IRQ_NONE)
1440 		return IRQ_NONE;
1441 
1442 	set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
1443 
1444 	if (unlikely(hcd->state == HC_STATE_HALT))
1445 		usb_hc_died (hcd);
1446 	return IRQ_HANDLED;
1447 }
1448 
1449 /*-------------------------------------------------------------------------*/
1450 
1451 /**
1452  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
1453  * @hcd: pointer to the HCD representing the controller
1454  *
1455  * This is called by bus glue to report a USB host controller that died
1456  * while operations may still have been pending.  It's called automatically
1457  * by the PCI glue, so only glue for non-PCI busses should need to call it.
1458  */
1459 void usb_hc_died (struct usb_hcd *hcd)
1460 {
1461 	unsigned long flags;
1462 
1463 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
1464 
1465 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
1466 	if (hcd->rh_registered) {
1467 		hcd->poll_rh = 0;
1468 
1469 		/* make khubd clean up old urbs and devices */
1470 		usb_set_device_state (hcd->self.root_hub,
1471 				USB_STATE_NOTATTACHED);
1472 		usb_kick_khubd (hcd->self.root_hub);
1473 	}
1474 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
1475 }
1476 EXPORT_SYMBOL_GPL (usb_hc_died);
1477 
1478 /*-------------------------------------------------------------------------*/
1479 
1480 /**
1481  * usb_create_hcd - create and initialize an HCD structure
1482  * @driver: HC driver that will use this hcd
1483  * @dev: device for this HC, stored in hcd->self.controller
1484  * @bus_name: value to store in hcd->self.bus_name
1485  * Context: !in_interrupt()
1486  *
1487  * Allocate a struct usb_hcd, with extra space at the end for the
1488  * HC driver's private data.  Initialize the generic members of the
1489  * hcd structure.
1490  *
1491  * If memory is unavailable, returns NULL.
1492  */
1493 struct usb_hcd *usb_create_hcd (const struct hc_driver *driver,
1494 		struct device *dev, char *bus_name)
1495 {
1496 	struct usb_hcd *hcd;
1497 
1498 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
1499 	if (!hcd) {
1500 		dev_dbg (dev, "hcd alloc failed\n");
1501 		return NULL;
1502 	}
1503 	dev_set_drvdata(dev, hcd);
1504 	kref_init(&hcd->kref);
1505 
1506 	usb_bus_init(&hcd->self);
1507 	hcd->self.controller = dev;
1508 	hcd->self.bus_name = bus_name;
1509 	hcd->self.uses_dma = (dev->dma_mask != NULL);
1510 
1511 	init_timer(&hcd->rh_timer);
1512 	hcd->rh_timer.function = rh_timer_func;
1513 	hcd->rh_timer.data = (unsigned long) hcd;
1514 #ifdef CONFIG_PM
1515 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
1516 #endif
1517 
1518 	hcd->driver = driver;
1519 	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
1520 			"USB Host Controller";
1521 
1522 	return hcd;
1523 }
1524 EXPORT_SYMBOL (usb_create_hcd);
1525 
1526 static void hcd_release (struct kref *kref)
1527 {
1528 	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
1529 
1530 	kfree(hcd);
1531 }
1532 
1533 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
1534 {
1535 	if (hcd)
1536 		kref_get (&hcd->kref);
1537 	return hcd;
1538 }
1539 EXPORT_SYMBOL (usb_get_hcd);
1540 
1541 void usb_put_hcd (struct usb_hcd *hcd)
1542 {
1543 	if (hcd)
1544 		kref_put (&hcd->kref, hcd_release);
1545 }
1546 EXPORT_SYMBOL (usb_put_hcd);
1547 
1548 /**
1549  * usb_add_hcd - finish generic HCD structure initialization and register
1550  * @hcd: the usb_hcd structure to initialize
1551  * @irqnum: Interrupt line to allocate
1552  * @irqflags: Interrupt type flags
1553  *
1554  * Finish the remaining parts of generic HCD initialization: allocate the
1555  * buffers of consistent memory, register the bus, request the IRQ line,
1556  * and call the driver's reset() and start() routines.
1557  */
1558 int usb_add_hcd(struct usb_hcd *hcd,
1559 		unsigned int irqnum, unsigned long irqflags)
1560 {
1561 	int retval;
1562 	struct usb_device *rhdev;
1563 
1564 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
1565 
1566 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1567 
1568 	/* HC is in reset state, but accessible.  Now do the one-time init,
1569 	 * bottom up so that hcds can customize the root hubs before khubd
1570 	 * starts talking to them.  (Note, bus id is assigned early too.)
1571 	 */
1572 	if ((retval = hcd_buffer_create(hcd)) != 0) {
1573 		dev_dbg(hcd->self.controller, "pool alloc failed\n");
1574 		return retval;
1575 	}
1576 
1577 	if ((retval = usb_register_bus(&hcd->self)) < 0)
1578 		goto err_register_bus;
1579 
1580 	if ((rhdev = usb_alloc_dev(NULL, &hcd->self, 0)) == NULL) {
1581 		dev_err(hcd->self.controller, "unable to allocate root hub\n");
1582 		retval = -ENOMEM;
1583 		goto err_allocate_root_hub;
1584 	}
1585 	rhdev->speed = (hcd->driver->flags & HCD_USB2) ? USB_SPEED_HIGH :
1586 			USB_SPEED_FULL;
1587 	hcd->self.root_hub = rhdev;
1588 
1589 	/* wakeup flag init defaults to "everything works" for root hubs,
1590 	 * but drivers can override it in reset() if needed, along with
1591 	 * recording the overall controller's system wakeup capability.
1592 	 */
1593 	device_init_wakeup(&rhdev->dev, 1);
1594 
1595 	/* "reset" is misnamed; its role is now one-time init. the controller
1596 	 * should already have been reset (and boot firmware kicked off etc).
1597 	 */
1598 	if (hcd->driver->reset && (retval = hcd->driver->reset(hcd)) < 0) {
1599 		dev_err(hcd->self.controller, "can't setup\n");
1600 		goto err_hcd_driver_setup;
1601 	}
1602 
1603 	/* NOTE: root hub and controller capabilities may not be the same */
1604 	if (device_can_wakeup(hcd->self.controller)
1605 			&& device_can_wakeup(&hcd->self.root_hub->dev))
1606 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
1607 
1608 	/* enable irqs just before we start the controller */
1609 	if (hcd->driver->irq) {
1610 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
1611 				hcd->driver->description, hcd->self.busnum);
1612 		if ((retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
1613 				hcd->irq_descr, hcd)) != 0) {
1614 			dev_err(hcd->self.controller,
1615 					"request interrupt %d failed\n", irqnum);
1616 			goto err_request_irq;
1617 		}
1618 		hcd->irq = irqnum;
1619 		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
1620 				(hcd->driver->flags & HCD_MEMORY) ?
1621 					"io mem" : "io base",
1622 					(unsigned long long)hcd->rsrc_start);
1623 	} else {
1624 		hcd->irq = -1;
1625 		if (hcd->rsrc_start)
1626 			dev_info(hcd->self.controller, "%s 0x%08llx\n",
1627 					(hcd->driver->flags & HCD_MEMORY) ?
1628 					"io mem" : "io base",
1629 					(unsigned long long)hcd->rsrc_start);
1630 	}
1631 
1632 	if ((retval = hcd->driver->start(hcd)) < 0) {
1633 		dev_err(hcd->self.controller, "startup error %d\n", retval);
1634 		goto err_hcd_driver_start;
1635 	}
1636 
1637 	/* starting here, usbcore will pay attention to this root hub */
1638 	rhdev->bus_mA = min(500u, hcd->power_budget);
1639 	if ((retval = register_root_hub(hcd)) != 0)
1640 		goto err_register_root_hub;
1641 
1642 	if (hcd->uses_new_polling && hcd->poll_rh)
1643 		usb_hcd_poll_rh_status(hcd);
1644 	return retval;
1645 
1646 err_register_root_hub:
1647 	hcd->driver->stop(hcd);
1648 err_hcd_driver_start:
1649 	if (hcd->irq >= 0)
1650 		free_irq(irqnum, hcd);
1651 err_request_irq:
1652 err_hcd_driver_setup:
1653 	hcd->self.root_hub = NULL;
1654 	usb_put_dev(rhdev);
1655 err_allocate_root_hub:
1656 	usb_deregister_bus(&hcd->self);
1657 err_register_bus:
1658 	hcd_buffer_destroy(hcd);
1659 	return retval;
1660 }
1661 EXPORT_SYMBOL (usb_add_hcd);
1662 
1663 /**
1664  * usb_remove_hcd - shutdown processing for generic HCDs
1665  * @hcd: the usb_hcd structure to remove
1666  * Context: !in_interrupt()
1667  *
1668  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
1669  * invoking the HCD's stop() method.
1670  */
1671 void usb_remove_hcd(struct usb_hcd *hcd)
1672 {
1673 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
1674 
1675 	if (HC_IS_RUNNING (hcd->state))
1676 		hcd->state = HC_STATE_QUIESCING;
1677 
1678 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
1679 	spin_lock_irq (&hcd_root_hub_lock);
1680 	hcd->rh_registered = 0;
1681 	spin_unlock_irq (&hcd_root_hub_lock);
1682 
1683 #ifdef CONFIG_PM
1684 	cancel_work_sync(&hcd->wakeup_work);
1685 #endif
1686 
1687 	mutex_lock(&usb_bus_list_lock);
1688 	usb_disconnect(&hcd->self.root_hub);
1689 	mutex_unlock(&usb_bus_list_lock);
1690 
1691 	hcd->driver->stop(hcd);
1692 	hcd->state = HC_STATE_HALT;
1693 
1694 	hcd->poll_rh = 0;
1695 	del_timer_sync(&hcd->rh_timer);
1696 
1697 	if (hcd->irq >= 0)
1698 		free_irq(hcd->irq, hcd);
1699 	usb_deregister_bus(&hcd->self);
1700 	hcd_buffer_destroy(hcd);
1701 }
1702 EXPORT_SYMBOL (usb_remove_hcd);
1703 
1704 void
1705 usb_hcd_platform_shutdown(struct platform_device* dev)
1706 {
1707 	struct usb_hcd *hcd = platform_get_drvdata(dev);
1708 
1709 	if (hcd->driver->shutdown)
1710 		hcd->driver->shutdown(hcd);
1711 }
1712 EXPORT_SYMBOL (usb_hcd_platform_shutdown);
1713 
1714 /*-------------------------------------------------------------------------*/
1715 
1716 #if defined(CONFIG_USB_MON)
1717 
1718 struct usb_mon_operations *mon_ops;
1719 
1720 /*
1721  * The registration is unlocked.
1722  * We do it this way because we do not want to lock in hot paths.
1723  *
1724  * Notice that the code is minimally error-proof. Because usbmon needs
1725  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
1726  */
1727 
1728 int usb_mon_register (struct usb_mon_operations *ops)
1729 {
1730 
1731 	if (mon_ops)
1732 		return -EBUSY;
1733 
1734 	mon_ops = ops;
1735 	mb();
1736 	return 0;
1737 }
1738 EXPORT_SYMBOL_GPL (usb_mon_register);
1739 
1740 void usb_mon_deregister (void)
1741 {
1742 
1743 	if (mon_ops == NULL) {
1744 		printk(KERN_ERR "USB: monitor was not registered\n");
1745 		return;
1746 	}
1747 	mon_ops = NULL;
1748 	mb();
1749 }
1750 EXPORT_SYMBOL_GPL (usb_mon_deregister);
1751 
1752 #endif /* CONFIG_USB_MON */
1753