xref: /linux/drivers/usb/host/ohci-hcd.c (revision 13abf8130139c2ccd4962a7e5a8902be5e6cb5a7)
1 /*
2  * OHCI HCD (Host Controller Driver) for USB.
3  *
4  * (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
5  * (C) Copyright 2000-2004 David Brownell <dbrownell@users.sourceforge.net>
6  *
7  * [ Initialisation is based on Linus'  ]
8  * [ uhci code and gregs ohci fragments ]
9  * [ (C) Copyright 1999 Linus Torvalds  ]
10  * [ (C) Copyright 1999 Gregory P. Smith]
11  *
12  *
13  * OHCI is the main "non-Intel/VIA" standard for USB 1.1 host controller
14  * interfaces (though some non-x86 Intel chips use it).  It supports
15  * smarter hardware than UHCI.  A download link for the spec available
16  * through the http://www.usb.org website.
17  *
18  * History:
19  *
20  * 2004/03/24 LH7A404 support (Durgesh Pattamatta & Marc Singer)
21  * 2004/02/04 use generic dma_* functions instead of pci_* (dsaxena@plexity.net)
22  * 2003/02/24 show registers in sysfs (Kevin Brosius)
23  *
24  * 2002/09/03 get rid of ed hashtables, rework periodic scheduling and
25  * 	bandwidth accounting; if debugging, show schedules in driverfs
26  * 2002/07/19 fixes to management of ED and schedule state.
27  * 2002/06/09 SA-1111 support (Christopher Hoover)
28  * 2002/06/01 remember frame when HC won't see EDs any more; use that info
29  *	to fix urb unlink races caused by interrupt latency assumptions;
30  *	minor ED field and function naming updates
31  * 2002/01/18 package as a patch for 2.5.3; this should match the
32  *	2.4.17 kernel modulo some bugs being fixed.
33  *
34  * 2001/10/18 merge pmac cleanup (Benjamin Herrenschmidt) and bugfixes
35  *	from post-2.4.5 patches.
36  * 2001/09/20 URB_ZERO_PACKET support; hcca_dma portability, OPTi warning
37  * 2001/09/07 match PCI PM changes, errnos from Linus' tree
38  * 2001/05/05 fork 2.4.5 version into "hcd" framework, cleanup, simplify;
39  *	pbook pci quirks gone (please fix pbook pci sw!) (db)
40  *
41  * 2001/04/08 Identify version on module load (gb)
42  * 2001/03/24 td/ed hashing to remove bus_to_virt (Steve Longerbeam);
43  	pci_map_single (db)
44  * 2001/03/21 td and dev/ed allocation uses new pci_pool API (db)
45  * 2001/03/07 hcca allocation uses pci_alloc_consistent (Steve Longerbeam)
46  *
47  * 2000/09/26 fixed races in removing the private portion of the urb
48  * 2000/09/07 disable bulk and control lists when unlinking the last
49  *	endpoint descriptor in order to avoid unrecoverable errors on
50  *	the Lucent chips. (rwc@sgi)
51  * 2000/08/29 use bandwidth claiming hooks (thanks Randy!), fix some
52  *	urb unlink probs, indentation fixes
53  * 2000/08/11 various oops fixes mostly affecting iso and cleanup from
54  *	device unplugs.
55  * 2000/06/28 use PCI hotplug framework, for better power management
56  *	and for Cardbus support (David Brownell)
57  * 2000/earlier:  fixes for NEC/Lucent chips; suspend/resume handling
58  *	when the controller loses power; handle UE; cleanup; ...
59  *
60  * v5.2 1999/12/07 URB 3rd preview,
61  * v5.1 1999/11/30 URB 2nd preview, cpia, (usb-scsi)
62  * v5.0 1999/11/22 URB Technical preview, Paul Mackerras powerbook susp/resume
63  * 	i386: HUB, Keyboard, Mouse, Printer
64  *
65  * v4.3 1999/10/27 multiple HCs, bulk_request
66  * v4.2 1999/09/05 ISO API alpha, new dev alloc, neg Error-codes
67  * v4.1 1999/08/27 Randy Dunlap's - ISO API first impl.
68  * v4.0 1999/08/18
69  * v3.0 1999/06/25
70  * v2.1 1999/05/09  code clean up
71  * v2.0 1999/05/04
72  * v1.0 1999/04/27 initial release
73  *
74  * This file is licenced under the GPL.
75  */
76 
77 #include <linux/config.h>
78 
79 #ifdef CONFIG_USB_DEBUG
80 #	define DEBUG
81 #else
82 #	undef DEBUG
83 #endif
84 
85 #include <linux/module.h>
86 #include <linux/moduleparam.h>
87 #include <linux/pci.h>
88 #include <linux/kernel.h>
89 #include <linux/delay.h>
90 #include <linux/ioport.h>
91 #include <linux/sched.h>
92 #include <linux/slab.h>
93 #include <linux/smp_lock.h>
94 #include <linux/errno.h>
95 #include <linux/init.h>
96 #include <linux/timer.h>
97 #include <linux/list.h>
98 #include <linux/usb.h>
99 #include <linux/usb_otg.h>
100 #include <linux/dma-mapping.h>
101 #include <linux/dmapool.h>
102 #include <linux/reboot.h>
103 
104 #include <asm/io.h>
105 #include <asm/irq.h>
106 #include <asm/system.h>
107 #include <asm/unaligned.h>
108 #include <asm/byteorder.h>
109 
110 #include "../core/hcd.h"
111 
112 #define DRIVER_VERSION "2005 April 22"
113 #define DRIVER_AUTHOR "Roman Weissgaerber, David Brownell"
114 #define DRIVER_DESC "USB 1.1 'Open' Host Controller (OHCI) Driver"
115 
116 /*-------------------------------------------------------------------------*/
117 
118 // #define OHCI_VERBOSE_DEBUG	/* not always helpful */
119 
120 /* For initializing controller (mask in an HCFS mode too) */
121 #define	OHCI_CONTROL_INIT 	OHCI_CTRL_CBSR
122 #define	OHCI_INTR_INIT \
123 	(OHCI_INTR_MIE | OHCI_INTR_UE | OHCI_INTR_RD | OHCI_INTR_WDH)
124 
125 #ifdef __hppa__
126 /* On PA-RISC, PDC can leave IR set incorrectly; ignore it there. */
127 #define	IR_DISABLE
128 #endif
129 
130 #ifdef CONFIG_ARCH_OMAP
131 /* OMAP doesn't support IR (no SMM; not needed) */
132 #define	IR_DISABLE
133 #endif
134 
135 /*-------------------------------------------------------------------------*/
136 
137 static const char	hcd_name [] = "ohci_hcd";
138 
139 #include "ohci.h"
140 
141 static void ohci_dump (struct ohci_hcd *ohci, int verbose);
142 static int ohci_init (struct ohci_hcd *ohci);
143 static void ohci_stop (struct usb_hcd *hcd);
144 static int ohci_reboot (struct notifier_block *, unsigned long , void *);
145 
146 #include "ohci-hub.c"
147 #include "ohci-dbg.c"
148 #include "ohci-mem.c"
149 #include "ohci-q.c"
150 
151 
152 /*
153  * On architectures with edge-triggered interrupts we must never return
154  * IRQ_NONE.
155  */
156 #if defined(CONFIG_SA1111)  /* ... or other edge-triggered systems */
157 #define IRQ_NOTMINE	IRQ_HANDLED
158 #else
159 #define IRQ_NOTMINE	IRQ_NONE
160 #endif
161 
162 
163 /* Some boards misreport power switching/overcurrent */
164 static int distrust_firmware = 1;
165 module_param (distrust_firmware, bool, 0);
166 MODULE_PARM_DESC (distrust_firmware,
167 	"true to distrust firmware power/overcurrent setup");
168 
169 /* Some boards leave IR set wrongly, since they fail BIOS/SMM handshakes */
170 static int no_handshake = 0;
171 module_param (no_handshake, bool, 0);
172 MODULE_PARM_DESC (no_handshake, "true (not default) disables BIOS handshake");
173 
174 /*-------------------------------------------------------------------------*/
175 
176 /*
177  * queue up an urb for anything except the root hub
178  */
179 static int ohci_urb_enqueue (
180 	struct usb_hcd	*hcd,
181 	struct usb_host_endpoint *ep,
182 	struct urb	*urb,
183 	unsigned	mem_flags
184 ) {
185 	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
186 	struct ed	*ed;
187 	urb_priv_t	*urb_priv;
188 	unsigned int	pipe = urb->pipe;
189 	int		i, size = 0;
190 	unsigned long	flags;
191 	int		retval = 0;
192 
193 #ifdef OHCI_VERBOSE_DEBUG
194 	urb_print (urb, "SUB", usb_pipein (pipe));
195 #endif
196 
197 	/* every endpoint has a ed, locate and maybe (re)initialize it */
198 	if (! (ed = ed_get (ohci, ep, urb->dev, pipe, urb->interval)))
199 		return -ENOMEM;
200 
201 	/* for the private part of the URB we need the number of TDs (size) */
202 	switch (ed->type) {
203 		case PIPE_CONTROL:
204 			/* td_submit_urb() doesn't yet handle these */
205 			if (urb->transfer_buffer_length > 4096)
206 				return -EMSGSIZE;
207 
208 			/* 1 TD for setup, 1 for ACK, plus ... */
209 			size = 2;
210 			/* FALLTHROUGH */
211 		// case PIPE_INTERRUPT:
212 		// case PIPE_BULK:
213 		default:
214 			/* one TD for every 4096 Bytes (can be upto 8K) */
215 			size += urb->transfer_buffer_length / 4096;
216 			/* ... and for any remaining bytes ... */
217 			if ((urb->transfer_buffer_length % 4096) != 0)
218 				size++;
219 			/* ... and maybe a zero length packet to wrap it up */
220 			if (size == 0)
221 				size++;
222 			else if ((urb->transfer_flags & URB_ZERO_PACKET) != 0
223 				&& (urb->transfer_buffer_length
224 					% usb_maxpacket (urb->dev, pipe,
225 						usb_pipeout (pipe))) == 0)
226 				size++;
227 			break;
228 		case PIPE_ISOCHRONOUS: /* number of packets from URB */
229 			size = urb->number_of_packets;
230 			break;
231 	}
232 
233 	/* allocate the private part of the URB */
234 	urb_priv = kmalloc (sizeof (urb_priv_t) + size * sizeof (struct td *),
235 			mem_flags);
236 	if (!urb_priv)
237 		return -ENOMEM;
238 	memset (urb_priv, 0, sizeof (urb_priv_t) + size * sizeof (struct td *));
239 	INIT_LIST_HEAD (&urb_priv->pending);
240 	urb_priv->length = size;
241 	urb_priv->ed = ed;
242 
243 	/* allocate the TDs (deferring hash chain updates) */
244 	for (i = 0; i < size; i++) {
245 		urb_priv->td [i] = td_alloc (ohci, mem_flags);
246 		if (!urb_priv->td [i]) {
247 			urb_priv->length = i;
248 			urb_free_priv (ohci, urb_priv);
249 			return -ENOMEM;
250 		}
251 	}
252 
253 	spin_lock_irqsave (&ohci->lock, flags);
254 
255 	/* don't submit to a dead HC */
256 	if (!HC_IS_RUNNING(hcd->state)) {
257 		retval = -ENODEV;
258 		goto fail;
259 	}
260 
261 	/* in case of unlink-during-submit */
262 	spin_lock (&urb->lock);
263 	if (urb->status != -EINPROGRESS) {
264 		spin_unlock (&urb->lock);
265 		urb->hcpriv = urb_priv;
266 		finish_urb (ohci, urb, NULL);
267 		retval = 0;
268 		goto fail;
269 	}
270 
271 	/* schedule the ed if needed */
272 	if (ed->state == ED_IDLE) {
273 		retval = ed_schedule (ohci, ed);
274 		if (retval < 0)
275 			goto fail0;
276 		if (ed->type == PIPE_ISOCHRONOUS) {
277 			u16	frame = ohci_frame_no(ohci);
278 
279 			/* delay a few frames before the first TD */
280 			frame += max_t (u16, 8, ed->interval);
281 			frame &= ~(ed->interval - 1);
282 			frame |= ed->branch;
283 			urb->start_frame = frame;
284 
285 			/* yes, only URB_ISO_ASAP is supported, and
286 			 * urb->start_frame is never used as input.
287 			 */
288 		}
289 	} else if (ed->type == PIPE_ISOCHRONOUS)
290 		urb->start_frame = ed->last_iso + ed->interval;
291 
292 	/* fill the TDs and link them to the ed; and
293 	 * enable that part of the schedule, if needed
294 	 * and update count of queued periodic urbs
295 	 */
296 	urb->hcpriv = urb_priv;
297 	td_submit_urb (ohci, urb);
298 
299 fail0:
300 	spin_unlock (&urb->lock);
301 fail:
302 	if (retval)
303 		urb_free_priv (ohci, urb_priv);
304 	spin_unlock_irqrestore (&ohci->lock, flags);
305 	return retval;
306 }
307 
308 /*
309  * decouple the URB from the HC queues (TDs, urb_priv); it's
310  * already marked using urb->status.  reporting is always done
311  * asynchronously, and we might be dealing with an urb that's
312  * partially transferred, or an ED with other urbs being unlinked.
313  */
314 static int ohci_urb_dequeue (struct usb_hcd *hcd, struct urb *urb)
315 {
316 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
317 	unsigned long		flags;
318 
319 #ifdef OHCI_VERBOSE_DEBUG
320 	urb_print (urb, "UNLINK", 1);
321 #endif
322 
323 	spin_lock_irqsave (&ohci->lock, flags);
324  	if (HC_IS_RUNNING(hcd->state)) {
325 		urb_priv_t  *urb_priv;
326 
327 		/* Unless an IRQ completed the unlink while it was being
328 		 * handed to us, flag it for unlink and giveback, and force
329 		 * some upcoming INTR_SF to call finish_unlinks()
330 		 */
331 		urb_priv = urb->hcpriv;
332 		if (urb_priv) {
333 			if (urb_priv->ed->state == ED_OPER)
334 				start_ed_unlink (ohci, urb_priv->ed);
335 		}
336 	} else {
337 		/*
338 		 * with HC dead, we won't respect hc queue pointers
339 		 * any more ... just clean up every urb's memory.
340 		 */
341 		if (urb->hcpriv)
342 			finish_urb (ohci, urb, NULL);
343 	}
344 	spin_unlock_irqrestore (&ohci->lock, flags);
345 	return 0;
346 }
347 
348 /*-------------------------------------------------------------------------*/
349 
350 /* frees config/altsetting state for endpoints,
351  * including ED memory, dummy TD, and bulk/intr data toggle
352  */
353 
354 static void
355 ohci_endpoint_disable (struct usb_hcd *hcd, struct usb_host_endpoint *ep)
356 {
357 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
358 	unsigned long		flags;
359 	struct ed		*ed = ep->hcpriv;
360 	unsigned		limit = 1000;
361 
362 	/* ASSERT:  any requests/urbs are being unlinked */
363 	/* ASSERT:  nobody can be submitting urbs for this any more */
364 
365 	if (!ed)
366 		return;
367 
368 rescan:
369 	spin_lock_irqsave (&ohci->lock, flags);
370 
371 	if (!HC_IS_RUNNING (hcd->state)) {
372 sanitize:
373 		ed->state = ED_IDLE;
374 		finish_unlinks (ohci, 0, NULL);
375 	}
376 
377 	switch (ed->state) {
378 	case ED_UNLINK:		/* wait for hw to finish? */
379 		/* major IRQ delivery trouble loses INTR_SF too... */
380 		if (limit-- == 0) {
381 			ohci_warn (ohci, "IRQ INTR_SF lossage\n");
382 			goto sanitize;
383 		}
384 		spin_unlock_irqrestore (&ohci->lock, flags);
385 		set_current_state (TASK_UNINTERRUPTIBLE);
386 		schedule_timeout (1);
387 		goto rescan;
388 	case ED_IDLE:		/* fully unlinked */
389 		if (list_empty (&ed->td_list)) {
390 			td_free (ohci, ed->dummy);
391 			ed_free (ohci, ed);
392 			break;
393 		}
394 		/* else FALL THROUGH */
395 	default:
396 		/* caller was supposed to have unlinked any requests;
397 		 * that's not our job.  can't recover; must leak ed.
398 		 */
399 		ohci_err (ohci, "leak ed %p (#%02x) state %d%s\n",
400 			ed, ep->desc.bEndpointAddress, ed->state,
401 			list_empty (&ed->td_list) ? "" : " (has tds)");
402 		td_free (ohci, ed->dummy);
403 		break;
404 	}
405 	ep->hcpriv = NULL;
406 	spin_unlock_irqrestore (&ohci->lock, flags);
407 	return;
408 }
409 
410 static int ohci_get_frame (struct usb_hcd *hcd)
411 {
412 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
413 
414 	return ohci_frame_no(ohci);
415 }
416 
417 static void ohci_usb_reset (struct ohci_hcd *ohci)
418 {
419 	ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
420 	ohci->hc_control &= OHCI_CTRL_RWC;
421 	ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
422 }
423 
424 /* reboot notifier forcibly disables IRQs and DMA, helping kexec and
425  * other cases where the next software may expect clean state from the
426  * "firmware".  this is bus-neutral, unlike shutdown() methods.
427  */
428 static int
429 ohci_reboot (struct notifier_block *block, unsigned long code, void *null)
430 {
431 	struct ohci_hcd *ohci;
432 
433 	ohci = container_of (block, struct ohci_hcd, reboot_notifier);
434 	ohci_writel (ohci, OHCI_INTR_MIE, &ohci->regs->intrdisable);
435 	ohci_usb_reset (ohci);
436 	/* flush the writes */
437 	(void) ohci_readl (ohci, &ohci->regs->control);
438 	return 0;
439 }
440 
441 /*-------------------------------------------------------------------------*
442  * HC functions
443  *-------------------------------------------------------------------------*/
444 
445 /* init memory, and kick BIOS/SMM off */
446 
447 static int ohci_init (struct ohci_hcd *ohci)
448 {
449 	int ret;
450 
451 	disable (ohci);
452 	ohci->regs = ohci_to_hcd(ohci)->regs;
453 	ohci->next_statechange = jiffies;
454 
455 #ifndef IR_DISABLE
456 	/* SMM owns the HC?  not for long! */
457 	if (!no_handshake && ohci_readl (ohci,
458 					&ohci->regs->control) & OHCI_CTRL_IR) {
459 		u32 temp;
460 
461 		ohci_dbg (ohci, "USB HC TakeOver from BIOS/SMM\n");
462 
463 		/* this timeout is arbitrary.  we make it long, so systems
464 		 * depending on usb keyboards may be usable even if the
465 		 * BIOS/SMM code seems pretty broken.
466 		 */
467 		temp = 500;	/* arbitrary: five seconds */
468 
469 		ohci_writel (ohci, OHCI_INTR_OC, &ohci->regs->intrenable);
470 		ohci_writel (ohci, OHCI_OCR, &ohci->regs->cmdstatus);
471 		while (ohci_readl (ohci, &ohci->regs->control) & OHCI_CTRL_IR) {
472 			msleep (10);
473 			if (--temp == 0) {
474 				ohci_err (ohci, "USB HC takeover failed!"
475 					"  (BIOS/SMM bug)\n");
476 				return -EBUSY;
477 			}
478 		}
479 		ohci_usb_reset (ohci);
480 	}
481 #endif
482 
483 	/* Disable HC interrupts */
484 	ohci_writel (ohci, OHCI_INTR_MIE, &ohci->regs->intrdisable);
485 	// flush the writes
486 	(void) ohci_readl (ohci, &ohci->regs->control);
487 
488 	if (ohci->hcca)
489 		return 0;
490 
491 	ohci->hcca = dma_alloc_coherent (ohci_to_hcd(ohci)->self.controller,
492 			sizeof *ohci->hcca, &ohci->hcca_dma, 0);
493 	if (!ohci->hcca)
494 		return -ENOMEM;
495 
496 	if ((ret = ohci_mem_init (ohci)) < 0)
497 		ohci_stop (ohci_to_hcd(ohci));
498 
499 	return ret;
500 
501 }
502 
503 /*-------------------------------------------------------------------------*/
504 
505 /* Start an OHCI controller, set the BUS operational
506  * resets USB and controller
507  * enable interrupts
508  */
509 static int ohci_run (struct ohci_hcd *ohci)
510 {
511   	u32			mask, temp;
512 	int			first = ohci->fminterval == 0;
513 
514 	disable (ohci);
515 
516 	/* boot firmware should have set this up (5.1.1.3.1) */
517 	if (first) {
518 
519 		temp = ohci_readl (ohci, &ohci->regs->fminterval);
520 		ohci->fminterval = temp & 0x3fff;
521 		if (ohci->fminterval != FI)
522 			ohci_dbg (ohci, "fminterval delta %d\n",
523 				ohci->fminterval - FI);
524 		ohci->fminterval |= FSMP (ohci->fminterval) << 16;
525 		/* also: power/overcurrent flags in roothub.a */
526 	}
527 
528   	/* Reset USB nearly "by the book".  RemoteWakeupConnected
529 	 * saved if boot firmware (BIOS/SMM/...) told us it's connected
530 	 * (for OHCI integrated on mainboard, it normally is)
531 	 */
532 	ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
533 	ohci_dbg (ohci, "resetting from state '%s', control = 0x%x\n",
534 			hcfs2string (ohci->hc_control & OHCI_CTRL_HCFS),
535 			ohci->hc_control);
536 
537 	if (ohci->hc_control & OHCI_CTRL_RWC
538 			&& !(ohci->flags & OHCI_QUIRK_AMD756))
539 		ohci_to_hcd(ohci)->can_wakeup = 1;
540 
541 	switch (ohci->hc_control & OHCI_CTRL_HCFS) {
542 	case OHCI_USB_OPER:
543 		temp = 0;
544 		break;
545 	case OHCI_USB_SUSPEND:
546 	case OHCI_USB_RESUME:
547 		ohci->hc_control &= OHCI_CTRL_RWC;
548 		ohci->hc_control |= OHCI_USB_RESUME;
549 		temp = 10 /* msec wait */;
550 		break;
551 	// case OHCI_USB_RESET:
552 	default:
553 		ohci->hc_control &= OHCI_CTRL_RWC;
554 		ohci->hc_control |= OHCI_USB_RESET;
555 		temp = 50 /* msec wait */;
556 		break;
557 	}
558 	ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
559 	// flush the writes
560 	(void) ohci_readl (ohci, &ohci->regs->control);
561 	msleep(temp);
562 	temp = roothub_a (ohci);
563 	if (!(temp & RH_A_NPS)) {
564 		unsigned ports = temp & RH_A_NDP;
565 
566 		/* power down each port */
567 		for (temp = 0; temp < ports; temp++)
568 			ohci_writel (ohci, RH_PS_LSDA,
569 				&ohci->regs->roothub.portstatus [temp]);
570 	}
571 	// flush those writes
572 	(void) ohci_readl (ohci, &ohci->regs->control);
573 	memset (ohci->hcca, 0, sizeof (struct ohci_hcca));
574 
575 	/* 2msec timelimit here means no irqs/preempt */
576 	spin_lock_irq (&ohci->lock);
577 
578 retry:
579 	/* HC Reset requires max 10 us delay */
580 	ohci_writel (ohci, OHCI_HCR,  &ohci->regs->cmdstatus);
581 	temp = 30;	/* ... allow extra time */
582 	while ((ohci_readl (ohci, &ohci->regs->cmdstatus) & OHCI_HCR) != 0) {
583 		if (--temp == 0) {
584 			spin_unlock_irq (&ohci->lock);
585 			ohci_err (ohci, "USB HC reset timed out!\n");
586 			return -1;
587 		}
588 		udelay (1);
589 	}
590 
591 	/* now we're in the SUSPEND state ... must go OPERATIONAL
592 	 * within 2msec else HC enters RESUME
593 	 *
594 	 * ... but some hardware won't init fmInterval "by the book"
595 	 * (SiS, OPTi ...), so reset again instead.  SiS doesn't need
596 	 * this if we write fmInterval after we're OPERATIONAL.
597 	 * Unclear about ALi, ServerWorks, and others ... this could
598 	 * easily be a longstanding bug in chip init on Linux.
599 	 */
600 	if (ohci->flags & OHCI_QUIRK_INITRESET) {
601 		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
602 		// flush those writes
603 		(void) ohci_readl (ohci, &ohci->regs->control);
604 	}
605 
606 	/* Tell the controller where the control and bulk lists are
607 	 * The lists are empty now. */
608 	ohci_writel (ohci, 0, &ohci->regs->ed_controlhead);
609 	ohci_writel (ohci, 0, &ohci->regs->ed_bulkhead);
610 
611 	/* a reset clears this */
612 	ohci_writel (ohci, (u32) ohci->hcca_dma, &ohci->regs->hcca);
613 
614 	periodic_reinit (ohci);
615 
616 	/* some OHCI implementations are finicky about how they init.
617 	 * bogus values here mean not even enumeration could work.
618 	 */
619 	if ((ohci_readl (ohci, &ohci->regs->fminterval) & 0x3fff0000) == 0
620 			|| !ohci_readl (ohci, &ohci->regs->periodicstart)) {
621 		if (!(ohci->flags & OHCI_QUIRK_INITRESET)) {
622 			ohci->flags |= OHCI_QUIRK_INITRESET;
623 			ohci_dbg (ohci, "enabling initreset quirk\n");
624 			goto retry;
625 		}
626 		spin_unlock_irq (&ohci->lock);
627 		ohci_err (ohci, "init err (%08x %04x)\n",
628 			ohci_readl (ohci, &ohci->regs->fminterval),
629 			ohci_readl (ohci, &ohci->regs->periodicstart));
630 		return -EOVERFLOW;
631 	}
632 
633  	/* start controller operations */
634 	ohci->hc_control &= OHCI_CTRL_RWC;
635  	ohci->hc_control |= OHCI_CONTROL_INIT | OHCI_USB_OPER;
636  	ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
637 	ohci_to_hcd(ohci)->state = HC_STATE_RUNNING;
638 
639 	/* wake on ConnectStatusChange, matching external hubs */
640 	ohci_writel (ohci, RH_HS_DRWE, &ohci->regs->roothub.status);
641 
642 	/* Choose the interrupts we care about now, others later on demand */
643 	mask = OHCI_INTR_INIT;
644 	ohci_writel (ohci, mask, &ohci->regs->intrstatus);
645 	ohci_writel (ohci, mask, &ohci->regs->intrenable);
646 
647 	/* handle root hub init quirks ... */
648 	temp = roothub_a (ohci);
649 	temp &= ~(RH_A_PSM | RH_A_OCPM);
650 	if (ohci->flags & OHCI_QUIRK_SUPERIO) {
651 		/* NSC 87560 and maybe others */
652 		temp |= RH_A_NOCP;
653 		temp &= ~(RH_A_POTPGT | RH_A_NPS);
654 		ohci_writel (ohci, temp, &ohci->regs->roothub.a);
655 	} else if ((ohci->flags & OHCI_QUIRK_AMD756) || distrust_firmware) {
656 		/* hub power always on; required for AMD-756 and some
657 		 * Mac platforms.  ganged overcurrent reporting, if any.
658 		 */
659 		temp |= RH_A_NPS;
660 		ohci_writel (ohci, temp, &ohci->regs->roothub.a);
661 	}
662 	ohci_writel (ohci, RH_HS_LPSC, &ohci->regs->roothub.status);
663 	ohci_writel (ohci, (temp & RH_A_NPS) ? 0 : RH_B_PPCM,
664 						&ohci->regs->roothub.b);
665 	// flush those writes
666 	(void) ohci_readl (ohci, &ohci->regs->control);
667 
668 	spin_unlock_irq (&ohci->lock);
669 
670 	// POTPGT delay is bits 24-31, in 2 ms units.
671 	mdelay ((temp >> 23) & 0x1fe);
672 	ohci_to_hcd(ohci)->state = HC_STATE_RUNNING;
673 
674 	ohci_dump (ohci, 1);
675 
676 	if (ohci_to_hcd(ohci)->self.root_hub == NULL) {
677 		register_reboot_notifier (&ohci->reboot_notifier);
678 		create_debug_files (ohci);
679 	}
680 
681 	return 0;
682 }
683 
684 /*-------------------------------------------------------------------------*/
685 
686 /* an interrupt happens */
687 
688 static irqreturn_t ohci_irq (struct usb_hcd *hcd, struct pt_regs *ptregs)
689 {
690 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
691 	struct ohci_regs __iomem *regs = ohci->regs;
692  	int			ints;
693 
694 	/* we can eliminate a (slow) ohci_readl()
695 	   if _only_ WDH caused this irq */
696 	if ((ohci->hcca->done_head != 0)
697 			&& ! (hc32_to_cpup (ohci, &ohci->hcca->done_head)
698 				& 0x01)) {
699 		ints =  OHCI_INTR_WDH;
700 
701 	/* cardbus/... hardware gone before remove() */
702 	} else if ((ints = ohci_readl (ohci, &regs->intrstatus)) == ~(u32)0) {
703 		disable (ohci);
704 		ohci_dbg (ohci, "device removed!\n");
705 		return IRQ_HANDLED;
706 
707 	/* interrupt for some other device? */
708 	} else if ((ints &= ohci_readl (ohci, &regs->intrenable)) == 0) {
709 		return IRQ_NOTMINE;
710 	}
711 
712 	if (ints & OHCI_INTR_UE) {
713 		disable (ohci);
714 		ohci_err (ohci, "OHCI Unrecoverable Error, disabled\n");
715 		// e.g. due to PCI Master/Target Abort
716 
717 		ohci_dump (ohci, 1);
718 		ohci_usb_reset (ohci);
719 	}
720 
721 	if (ints & OHCI_INTR_RD) {
722 		ohci_vdbg (ohci, "resume detect\n");
723 		if (hcd->state != HC_STATE_QUIESCING)
724 			schedule_work(&ohci->rh_resume);
725 	}
726 
727 	if (ints & OHCI_INTR_WDH) {
728 		if (HC_IS_RUNNING(hcd->state))
729 			ohci_writel (ohci, OHCI_INTR_WDH, &regs->intrdisable);
730 		spin_lock (&ohci->lock);
731 		dl_done_list (ohci, ptregs);
732 		spin_unlock (&ohci->lock);
733 		if (HC_IS_RUNNING(hcd->state))
734 			ohci_writel (ohci, OHCI_INTR_WDH, &regs->intrenable);
735 	}
736 
737 	/* could track INTR_SO to reduce available PCI/... bandwidth */
738 
739 	/* handle any pending URB/ED unlinks, leaving INTR_SF enabled
740 	 * when there's still unlinking to be done (next frame).
741 	 */
742 	spin_lock (&ohci->lock);
743 	if (ohci->ed_rm_list)
744 		finish_unlinks (ohci, ohci_frame_no(ohci), ptregs);
745 	if ((ints & OHCI_INTR_SF) != 0 && !ohci->ed_rm_list
746 			&& HC_IS_RUNNING(hcd->state))
747 		ohci_writel (ohci, OHCI_INTR_SF, &regs->intrdisable);
748 	spin_unlock (&ohci->lock);
749 
750 	if (HC_IS_RUNNING(hcd->state)) {
751 		ohci_writel (ohci, ints, &regs->intrstatus);
752 		ohci_writel (ohci, OHCI_INTR_MIE, &regs->intrenable);
753 		// flush those writes
754 		(void) ohci_readl (ohci, &ohci->regs->control);
755 	}
756 
757 	return IRQ_HANDLED;
758 }
759 
760 /*-------------------------------------------------------------------------*/
761 
762 static void ohci_stop (struct usb_hcd *hcd)
763 {
764 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
765 
766 	ohci_dbg (ohci, "stop %s controller (state 0x%02x)\n",
767 		hcfs2string (ohci->hc_control & OHCI_CTRL_HCFS),
768 		hcd->state);
769 	ohci_dump (ohci, 1);
770 
771 	flush_scheduled_work();
772 
773 	ohci_usb_reset (ohci);
774 	ohci_writel (ohci, OHCI_INTR_MIE, &ohci->regs->intrdisable);
775 
776 	remove_debug_files (ohci);
777 	unregister_reboot_notifier (&ohci->reboot_notifier);
778 	ohci_mem_cleanup (ohci);
779 	if (ohci->hcca) {
780 		dma_free_coherent (hcd->self.controller,
781 				sizeof *ohci->hcca,
782 				ohci->hcca, ohci->hcca_dma);
783 		ohci->hcca = NULL;
784 		ohci->hcca_dma = 0;
785 	}
786 }
787 
788 /*-------------------------------------------------------------------------*/
789 
790 /* must not be called from interrupt context */
791 
792 #if	defined(CONFIG_USB_SUSPEND) || defined(CONFIG_PM)
793 
794 static int ohci_restart (struct ohci_hcd *ohci)
795 {
796 	int temp;
797 	int i;
798 	struct urb_priv *priv;
799 	struct usb_device *root = ohci_to_hcd(ohci)->self.root_hub;
800 
801 	/* mark any devices gone, so they do nothing till khubd disconnects.
802 	 * recycle any "live" eds/tds (and urbs) right away.
803 	 * later, khubd disconnect processing will recycle the other state,
804 	 * (either as disconnect/reconnect, or maybe someday as a reset).
805 	 */
806 	spin_lock_irq(&ohci->lock);
807 	disable (ohci);
808 	for (i = 0; i < root->maxchild; i++) {
809 		if (root->children [i])
810 			usb_set_device_state (root->children[i],
811 				USB_STATE_NOTATTACHED);
812 	}
813 	if (!list_empty (&ohci->pending))
814 		ohci_dbg(ohci, "abort schedule...\n");
815 	list_for_each_entry (priv, &ohci->pending, pending) {
816 		struct urb	*urb = priv->td[0]->urb;
817 		struct ed	*ed = priv->ed;
818 
819 		switch (ed->state) {
820 		case ED_OPER:
821 			ed->state = ED_UNLINK;
822 			ed->hwINFO |= cpu_to_hc32(ohci, ED_DEQUEUE);
823 			ed_deschedule (ohci, ed);
824 
825 			ed->ed_next = ohci->ed_rm_list;
826 			ed->ed_prev = NULL;
827 			ohci->ed_rm_list = ed;
828 			/* FALLTHROUGH */
829 		case ED_UNLINK:
830 			break;
831 		default:
832 			ohci_dbg(ohci, "bogus ed %p state %d\n",
833 					ed, ed->state);
834 		}
835 
836 		spin_lock (&urb->lock);
837 		urb->status = -ESHUTDOWN;
838 		spin_unlock (&urb->lock);
839 	}
840 	finish_unlinks (ohci, 0, NULL);
841 	spin_unlock_irq(&ohci->lock);
842 
843 	/* paranoia, in case that didn't work: */
844 
845 	/* empty the interrupt branches */
846 	for (i = 0; i < NUM_INTS; i++) ohci->load [i] = 0;
847 	for (i = 0; i < NUM_INTS; i++) ohci->hcca->int_table [i] = 0;
848 
849 	/* no EDs to remove */
850 	ohci->ed_rm_list = NULL;
851 
852 	/* empty control and bulk lists */
853 	ohci->ed_controltail = NULL;
854 	ohci->ed_bulktail    = NULL;
855 
856 	if ((temp = ohci_run (ohci)) < 0) {
857 		ohci_err (ohci, "can't restart, %d\n", temp);
858 		return temp;
859 	} else {
860 		/* here we "know" root ports should always stay powered,
861 		 * and that if we try to turn them back on the root hub
862 		 * will respond to CSC processing.
863 		 */
864 		i = roothub_a (ohci) & RH_A_NDP;
865 		while (i--)
866 			ohci_writel (ohci, RH_PS_PSS,
867 				&ohci->regs->roothub.portstatus [temp]);
868 		ohci_dbg (ohci, "restart complete\n");
869 	}
870 	return 0;
871 }
872 #endif
873 
874 /*-------------------------------------------------------------------------*/
875 
876 #define DRIVER_INFO DRIVER_VERSION " " DRIVER_DESC
877 
878 MODULE_AUTHOR (DRIVER_AUTHOR);
879 MODULE_DESCRIPTION (DRIVER_INFO);
880 MODULE_LICENSE ("GPL");
881 
882 #ifdef CONFIG_PCI
883 #include "ohci-pci.c"
884 #endif
885 
886 #ifdef CONFIG_SA1111
887 #include "ohci-sa1111.c"
888 #endif
889 
890 #ifdef CONFIG_ARCH_S3C2410
891 #include "ohci-s3c2410.c"
892 #endif
893 
894 #ifdef CONFIG_ARCH_OMAP
895 #include "ohci-omap.c"
896 #endif
897 
898 #ifdef CONFIG_ARCH_LH7A404
899 #include "ohci-lh7a404.c"
900 #endif
901 
902 #ifdef CONFIG_PXA27x
903 #include "ohci-pxa27x.c"
904 #endif
905 
906 #ifdef CONFIG_SOC_AU1X00
907 #include "ohci-au1xxx.c"
908 #endif
909 
910 #ifdef CONFIG_USB_OHCI_HCD_PPC_SOC
911 #include "ohci-ppc-soc.c"
912 #endif
913 
914 #if !(defined(CONFIG_PCI) \
915       || defined(CONFIG_SA1111) \
916       || defined(CONFIG_ARCH_S3C2410) \
917       || defined(CONFIG_ARCH_OMAP) \
918       || defined (CONFIG_ARCH_LH7A404) \
919       || defined (CONFIG_PXA27x) \
920       || defined (CONFIG_SOC_AU1X00) \
921       || defined (CONFIG_USB_OHCI_HCD_PPC_SOC) \
922 	)
923 #error "missing bus glue for ohci-hcd"
924 #endif
925