xref: /openbmc/linux/drivers/usb/host/ohci-hcd.c (revision 583ceada)
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/module.h>
78 #include <linux/moduleparam.h>
79 #include <linux/pci.h>
80 #include <linux/kernel.h>
81 #include <linux/delay.h>
82 #include <linux/ioport.h>
83 #include <linux/sched.h>
84 #include <linux/slab.h>
85 #include <linux/smp_lock.h>
86 #include <linux/errno.h>
87 #include <linux/init.h>
88 #include <linux/timer.h>
89 #include <linux/list.h>
90 #include <linux/usb.h>
91 #include <linux/usb/otg.h>
92 #include <linux/dma-mapping.h>
93 #include <linux/dmapool.h>
94 #include <linux/reboot.h>
95 
96 #include <asm/io.h>
97 #include <asm/irq.h>
98 #include <asm/system.h>
99 #include <asm/unaligned.h>
100 #include <asm/byteorder.h>
101 
102 #include "../core/hcd.h"
103 
104 #define DRIVER_VERSION "2006 August 04"
105 #define DRIVER_AUTHOR "Roman Weissgaerber, David Brownell"
106 #define DRIVER_DESC "USB 1.1 'Open' Host Controller (OHCI) Driver"
107 
108 /*-------------------------------------------------------------------------*/
109 
110 #undef OHCI_VERBOSE_DEBUG	/* not always helpful */
111 
112 /* For initializing controller (mask in an HCFS mode too) */
113 #define	OHCI_CONTROL_INIT	OHCI_CTRL_CBSR
114 #define	OHCI_INTR_INIT \
115 		(OHCI_INTR_MIE | OHCI_INTR_RHSC | OHCI_INTR_UE \
116 		| OHCI_INTR_RD | OHCI_INTR_WDH)
117 
118 #ifdef __hppa__
119 /* On PA-RISC, PDC can leave IR set incorrectly; ignore it there. */
120 #define	IR_DISABLE
121 #endif
122 
123 #ifdef CONFIG_ARCH_OMAP
124 /* OMAP doesn't support IR (no SMM; not needed) */
125 #define	IR_DISABLE
126 #endif
127 
128 /*-------------------------------------------------------------------------*/
129 
130 static const char	hcd_name [] = "ohci_hcd";
131 
132 #define	STATECHANGE_DELAY	msecs_to_jiffies(300)
133 
134 #include "ohci.h"
135 
136 static void ohci_dump (struct ohci_hcd *ohci, int verbose);
137 static int ohci_init (struct ohci_hcd *ohci);
138 static void ohci_stop (struct usb_hcd *hcd);
139 
140 #include "ohci-hub.c"
141 #include "ohci-dbg.c"
142 #include "ohci-mem.c"
143 #include "ohci-q.c"
144 
145 
146 /*
147  * On architectures with edge-triggered interrupts we must never return
148  * IRQ_NONE.
149  */
150 #if defined(CONFIG_SA1111)  /* ... or other edge-triggered systems */
151 #define IRQ_NOTMINE	IRQ_HANDLED
152 #else
153 #define IRQ_NOTMINE	IRQ_NONE
154 #endif
155 
156 
157 /* Some boards misreport power switching/overcurrent */
158 static int distrust_firmware = 1;
159 module_param (distrust_firmware, bool, 0);
160 MODULE_PARM_DESC (distrust_firmware,
161 	"true to distrust firmware power/overcurrent setup");
162 
163 /* Some boards leave IR set wrongly, since they fail BIOS/SMM handshakes */
164 static int no_handshake = 0;
165 module_param (no_handshake, bool, 0);
166 MODULE_PARM_DESC (no_handshake, "true (not default) disables BIOS handshake");
167 
168 /*-------------------------------------------------------------------------*/
169 
170 /*
171  * queue up an urb for anything except the root hub
172  */
173 static int ohci_urb_enqueue (
174 	struct usb_hcd	*hcd,
175 	struct usb_host_endpoint *ep,
176 	struct urb	*urb,
177 	gfp_t		mem_flags
178 ) {
179 	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
180 	struct ed	*ed;
181 	urb_priv_t	*urb_priv;
182 	unsigned int	pipe = urb->pipe;
183 	int		i, size = 0;
184 	unsigned long	flags;
185 	int		retval = 0;
186 
187 #ifdef OHCI_VERBOSE_DEBUG
188 	urb_print (urb, "SUB", usb_pipein (pipe));
189 #endif
190 
191 	/* every endpoint has a ed, locate and maybe (re)initialize it */
192 	if (! (ed = ed_get (ohci, ep, urb->dev, pipe, urb->interval)))
193 		return -ENOMEM;
194 
195 	/* for the private part of the URB we need the number of TDs (size) */
196 	switch (ed->type) {
197 		case PIPE_CONTROL:
198 			/* td_submit_urb() doesn't yet handle these */
199 			if (urb->transfer_buffer_length > 4096)
200 				return -EMSGSIZE;
201 
202 			/* 1 TD for setup, 1 for ACK, plus ... */
203 			size = 2;
204 			/* FALLTHROUGH */
205 		// case PIPE_INTERRUPT:
206 		// case PIPE_BULK:
207 		default:
208 			/* one TD for every 4096 Bytes (can be upto 8K) */
209 			size += urb->transfer_buffer_length / 4096;
210 			/* ... and for any remaining bytes ... */
211 			if ((urb->transfer_buffer_length % 4096) != 0)
212 				size++;
213 			/* ... and maybe a zero length packet to wrap it up */
214 			if (size == 0)
215 				size++;
216 			else if ((urb->transfer_flags & URB_ZERO_PACKET) != 0
217 				&& (urb->transfer_buffer_length
218 					% usb_maxpacket (urb->dev, pipe,
219 						usb_pipeout (pipe))) == 0)
220 				size++;
221 			break;
222 		case PIPE_ISOCHRONOUS: /* number of packets from URB */
223 			size = urb->number_of_packets;
224 			break;
225 	}
226 
227 	/* allocate the private part of the URB */
228 	urb_priv = kmalloc (sizeof (urb_priv_t) + size * sizeof (struct td *),
229 			mem_flags);
230 	if (!urb_priv)
231 		return -ENOMEM;
232 	memset (urb_priv, 0, sizeof (urb_priv_t) + size * sizeof (struct td *));
233 	INIT_LIST_HEAD (&urb_priv->pending);
234 	urb_priv->length = size;
235 	urb_priv->ed = ed;
236 
237 	/* allocate the TDs (deferring hash chain updates) */
238 	for (i = 0; i < size; i++) {
239 		urb_priv->td [i] = td_alloc (ohci, mem_flags);
240 		if (!urb_priv->td [i]) {
241 			urb_priv->length = i;
242 			urb_free_priv (ohci, urb_priv);
243 			return -ENOMEM;
244 		}
245 	}
246 
247 	spin_lock_irqsave (&ohci->lock, flags);
248 
249 	/* don't submit to a dead HC */
250 	if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)) {
251 		retval = -ENODEV;
252 		goto fail;
253 	}
254 	if (!HC_IS_RUNNING(hcd->state)) {
255 		retval = -ENODEV;
256 		goto fail;
257 	}
258 
259 	/* in case of unlink-during-submit */
260 	spin_lock (&urb->lock);
261 	if (urb->status != -EINPROGRESS) {
262 		spin_unlock (&urb->lock);
263 		urb->hcpriv = urb_priv;
264 		finish_urb (ohci, urb);
265 		retval = 0;
266 		goto fail;
267 	}
268 
269 	/* schedule the ed if needed */
270 	if (ed->state == ED_IDLE) {
271 		retval = ed_schedule (ohci, ed);
272 		if (retval < 0)
273 			goto fail0;
274 		if (ed->type == PIPE_ISOCHRONOUS) {
275 			u16	frame = ohci_frame_no(ohci);
276 
277 			/* delay a few frames before the first TD */
278 			frame += max_t (u16, 8, ed->interval);
279 			frame &= ~(ed->interval - 1);
280 			frame |= ed->branch;
281 			urb->start_frame = frame;
282 
283 			/* yes, only URB_ISO_ASAP is supported, and
284 			 * urb->start_frame is never used as input.
285 			 */
286 		}
287 	} else if (ed->type == PIPE_ISOCHRONOUS)
288 		urb->start_frame = ed->last_iso + ed->interval;
289 
290 	/* fill the TDs and link them to the ed; and
291 	 * enable that part of the schedule, if needed
292 	 * and update count of queued periodic urbs
293 	 */
294 	urb->hcpriv = urb_priv;
295 	td_submit_urb (ohci, urb);
296 
297 fail0:
298 	spin_unlock (&urb->lock);
299 fail:
300 	if (retval)
301 		urb_free_priv (ohci, urb_priv);
302 	spin_unlock_irqrestore (&ohci->lock, flags);
303 	return retval;
304 }
305 
306 /*
307  * decouple the URB from the HC queues (TDs, urb_priv); it's
308  * already marked using urb->status.  reporting is always done
309  * asynchronously, and we might be dealing with an urb that's
310  * partially transferred, or an ED with other urbs being unlinked.
311  */
312 static int ohci_urb_dequeue (struct usb_hcd *hcd, struct urb *urb)
313 {
314 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
315 	unsigned long		flags;
316 
317 #ifdef OHCI_VERBOSE_DEBUG
318 	urb_print (urb, "UNLINK", 1);
319 #endif
320 
321 	spin_lock_irqsave (&ohci->lock, flags);
322  	if (HC_IS_RUNNING(hcd->state)) {
323 		urb_priv_t  *urb_priv;
324 
325 		/* Unless an IRQ completed the unlink while it was being
326 		 * handed to us, flag it for unlink and giveback, and force
327 		 * some upcoming INTR_SF to call finish_unlinks()
328 		 */
329 		urb_priv = urb->hcpriv;
330 		if (urb_priv) {
331 			if (urb_priv->ed->state == ED_OPER)
332 				start_ed_unlink (ohci, urb_priv->ed);
333 		}
334 	} else {
335 		/*
336 		 * with HC dead, we won't respect hc queue pointers
337 		 * any more ... just clean up every urb's memory.
338 		 */
339 		if (urb->hcpriv)
340 			finish_urb (ohci, urb);
341 	}
342 	spin_unlock_irqrestore (&ohci->lock, flags);
343 	return 0;
344 }
345 
346 /*-------------------------------------------------------------------------*/
347 
348 /* frees config/altsetting state for endpoints,
349  * including ED memory, dummy TD, and bulk/intr data toggle
350  */
351 
352 static void
353 ohci_endpoint_disable (struct usb_hcd *hcd, struct usb_host_endpoint *ep)
354 {
355 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
356 	unsigned long		flags;
357 	struct ed		*ed = ep->hcpriv;
358 	unsigned		limit = 1000;
359 
360 	/* ASSERT:  any requests/urbs are being unlinked */
361 	/* ASSERT:  nobody can be submitting urbs for this any more */
362 
363 	if (!ed)
364 		return;
365 
366 rescan:
367 	spin_lock_irqsave (&ohci->lock, flags);
368 
369 	if (!HC_IS_RUNNING (hcd->state)) {
370 sanitize:
371 		ed->state = ED_IDLE;
372 		finish_unlinks (ohci, 0);
373 	}
374 
375 	switch (ed->state) {
376 	case ED_UNLINK:		/* wait for hw to finish? */
377 		/* major IRQ delivery trouble loses INTR_SF too... */
378 		if (limit-- == 0) {
379 			ohci_warn (ohci, "IRQ INTR_SF lossage\n");
380 			goto sanitize;
381 		}
382 		spin_unlock_irqrestore (&ohci->lock, flags);
383 		schedule_timeout_uninterruptible(1);
384 		goto rescan;
385 	case ED_IDLE:		/* fully unlinked */
386 		if (list_empty (&ed->td_list)) {
387 			td_free (ohci, ed->dummy);
388 			ed_free (ohci, ed);
389 			break;
390 		}
391 		/* else FALL THROUGH */
392 	default:
393 		/* caller was supposed to have unlinked any requests;
394 		 * that's not our job.  can't recover; must leak ed.
395 		 */
396 		ohci_err (ohci, "leak ed %p (#%02x) state %d%s\n",
397 			ed, ep->desc.bEndpointAddress, ed->state,
398 			list_empty (&ed->td_list) ? "" : " (has tds)");
399 		td_free (ohci, ed->dummy);
400 		break;
401 	}
402 	ep->hcpriv = NULL;
403 	spin_unlock_irqrestore (&ohci->lock, flags);
404 	return;
405 }
406 
407 static int ohci_get_frame (struct usb_hcd *hcd)
408 {
409 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
410 
411 	return ohci_frame_no(ohci);
412 }
413 
414 static void ohci_usb_reset (struct ohci_hcd *ohci)
415 {
416 	ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
417 	ohci->hc_control &= OHCI_CTRL_RWC;
418 	ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
419 }
420 
421 /* ohci_shutdown forcibly disables IRQs and DMA, helping kexec and
422  * other cases where the next software may expect clean state from the
423  * "firmware".  this is bus-neutral, unlike shutdown() methods.
424  */
425 static void
426 ohci_shutdown (struct usb_hcd *hcd)
427 {
428 	struct ohci_hcd *ohci;
429 
430 	ohci = hcd_to_ohci (hcd);
431 	ohci_writel (ohci, OHCI_INTR_MIE, &ohci->regs->intrdisable);
432 	ohci_usb_reset (ohci);
433 	/* flush the writes */
434 	(void) ohci_readl (ohci, &ohci->regs->control);
435 }
436 
437 /*-------------------------------------------------------------------------*
438  * HC functions
439  *-------------------------------------------------------------------------*/
440 
441 /* init memory, and kick BIOS/SMM off */
442 
443 static int ohci_init (struct ohci_hcd *ohci)
444 {
445 	int ret;
446 	struct usb_hcd *hcd = ohci_to_hcd(ohci);
447 
448 	disable (ohci);
449 	ohci->regs = hcd->regs;
450 
451 	/* REVISIT this BIOS handshake is now moved into PCI "quirks", and
452 	 * was never needed for most non-PCI systems ... remove the code?
453 	 */
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 
486 	/* flush the writes, and save key bits like RWC */
487 	if (ohci_readl (ohci, &ohci->regs->control) & OHCI_CTRL_RWC)
488 		ohci->hc_control |= OHCI_CTRL_RWC;
489 
490 	/* Read the number of ports unless overridden */
491 	if (ohci->num_ports == 0)
492 		ohci->num_ports = roothub_a(ohci) & RH_A_NDP;
493 
494 	if (ohci->hcca)
495 		return 0;
496 
497 	ohci->hcca = dma_alloc_coherent (hcd->self.controller,
498 			sizeof *ohci->hcca, &ohci->hcca_dma, 0);
499 	if (!ohci->hcca)
500 		return -ENOMEM;
501 
502 	if ((ret = ohci_mem_init (ohci)) < 0)
503 		ohci_stop (hcd);
504 	else {
505 		create_debug_files (ohci);
506 	}
507 
508 	return ret;
509 }
510 
511 /*-------------------------------------------------------------------------*/
512 
513 /* Start an OHCI controller, set the BUS operational
514  * resets USB and controller
515  * enable interrupts
516  */
517 static int ohci_run (struct ohci_hcd *ohci)
518 {
519   	u32			mask, temp;
520 	int			first = ohci->fminterval == 0;
521 	struct usb_hcd		*hcd = ohci_to_hcd(ohci);
522 
523 	disable (ohci);
524 
525 	/* boot firmware should have set this up (5.1.1.3.1) */
526 	if (first) {
527 
528 		temp = ohci_readl (ohci, &ohci->regs->fminterval);
529 		ohci->fminterval = temp & 0x3fff;
530 		if (ohci->fminterval != FI)
531 			ohci_dbg (ohci, "fminterval delta %d\n",
532 				ohci->fminterval - FI);
533 		ohci->fminterval |= FSMP (ohci->fminterval) << 16;
534 		/* also: power/overcurrent flags in roothub.a */
535 	}
536 
537   	/* Reset USB nearly "by the book".  RemoteWakeupConnected was
538 	 * saved if boot firmware (BIOS/SMM/...) told us it's connected,
539 	 * or if bus glue did the same (e.g. for PCI add-in cards with
540 	 * PCI PM support).
541 	 */
542 	ohci_dbg (ohci, "resetting from state '%s', control = 0x%x\n",
543 			hcfs2string (ohci->hc_control & OHCI_CTRL_HCFS),
544 			ohci_readl (ohci, &ohci->regs->control));
545 	if ((ohci->hc_control & OHCI_CTRL_RWC) != 0
546 			&& !device_may_wakeup(hcd->self.controller))
547 		device_init_wakeup(hcd->self.controller, 1);
548 
549 	switch (ohci->hc_control & OHCI_CTRL_HCFS) {
550 	case OHCI_USB_OPER:
551 		temp = 0;
552 		break;
553 	case OHCI_USB_SUSPEND:
554 	case OHCI_USB_RESUME:
555 		ohci->hc_control &= OHCI_CTRL_RWC;
556 		ohci->hc_control |= OHCI_USB_RESUME;
557 		temp = 10 /* msec wait */;
558 		break;
559 	// case OHCI_USB_RESET:
560 	default:
561 		ohci->hc_control &= OHCI_CTRL_RWC;
562 		ohci->hc_control |= OHCI_USB_RESET;
563 		temp = 50 /* msec wait */;
564 		break;
565 	}
566 	ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
567 	// flush the writes
568 	(void) ohci_readl (ohci, &ohci->regs->control);
569 	msleep(temp);
570 	temp = roothub_a (ohci);
571 	if (!(temp & RH_A_NPS)) {
572 		/* power down each port */
573 		for (temp = 0; temp < ohci->num_ports; temp++)
574 			ohci_writel (ohci, RH_PS_LSDA,
575 				&ohci->regs->roothub.portstatus [temp]);
576 	}
577 	// flush those writes
578 	(void) ohci_readl (ohci, &ohci->regs->control);
579 	memset (ohci->hcca, 0, sizeof (struct ohci_hcca));
580 
581 	/* 2msec timelimit here means no irqs/preempt */
582 	spin_lock_irq (&ohci->lock);
583 
584 retry:
585 	/* HC Reset requires max 10 us delay */
586 	ohci_writel (ohci, OHCI_HCR,  &ohci->regs->cmdstatus);
587 	temp = 30;	/* ... allow extra time */
588 	while ((ohci_readl (ohci, &ohci->regs->cmdstatus) & OHCI_HCR) != 0) {
589 		if (--temp == 0) {
590 			spin_unlock_irq (&ohci->lock);
591 			ohci_err (ohci, "USB HC reset timed out!\n");
592 			return -1;
593 		}
594 		udelay (1);
595 	}
596 
597 	/* now we're in the SUSPEND state ... must go OPERATIONAL
598 	 * within 2msec else HC enters RESUME
599 	 *
600 	 * ... but some hardware won't init fmInterval "by the book"
601 	 * (SiS, OPTi ...), so reset again instead.  SiS doesn't need
602 	 * this if we write fmInterval after we're OPERATIONAL.
603 	 * Unclear about ALi, ServerWorks, and others ... this could
604 	 * easily be a longstanding bug in chip init on Linux.
605 	 */
606 	if (ohci->flags & OHCI_QUIRK_INITRESET) {
607 		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
608 		// flush those writes
609 		(void) ohci_readl (ohci, &ohci->regs->control);
610 	}
611 
612 	/* Tell the controller where the control and bulk lists are
613 	 * The lists are empty now. */
614 	ohci_writel (ohci, 0, &ohci->regs->ed_controlhead);
615 	ohci_writel (ohci, 0, &ohci->regs->ed_bulkhead);
616 
617 	/* a reset clears this */
618 	ohci_writel (ohci, (u32) ohci->hcca_dma, &ohci->regs->hcca);
619 
620 	periodic_reinit (ohci);
621 
622 	/* some OHCI implementations are finicky about how they init.
623 	 * bogus values here mean not even enumeration could work.
624 	 */
625 	if ((ohci_readl (ohci, &ohci->regs->fminterval) & 0x3fff0000) == 0
626 			|| !ohci_readl (ohci, &ohci->regs->periodicstart)) {
627 		if (!(ohci->flags & OHCI_QUIRK_INITRESET)) {
628 			ohci->flags |= OHCI_QUIRK_INITRESET;
629 			ohci_dbg (ohci, "enabling initreset quirk\n");
630 			goto retry;
631 		}
632 		spin_unlock_irq (&ohci->lock);
633 		ohci_err (ohci, "init err (%08x %04x)\n",
634 			ohci_readl (ohci, &ohci->regs->fminterval),
635 			ohci_readl (ohci, &ohci->regs->periodicstart));
636 		return -EOVERFLOW;
637 	}
638 
639 	/* use rhsc irqs after khubd is fully initialized */
640 	hcd->poll_rh = 1;
641 	hcd->uses_new_polling = 1;
642 
643 	/* start controller operations */
644 	ohci->hc_control &= OHCI_CTRL_RWC;
645 	ohci->hc_control |= OHCI_CONTROL_INIT | OHCI_USB_OPER;
646 	ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
647 	hcd->state = HC_STATE_RUNNING;
648 
649 	/* wake on ConnectStatusChange, matching external hubs */
650 	ohci_writel (ohci, RH_HS_DRWE, &ohci->regs->roothub.status);
651 
652 	/* Choose the interrupts we care about now, others later on demand */
653 	mask = OHCI_INTR_INIT;
654 	ohci_writel (ohci, ~0, &ohci->regs->intrstatus);
655 	ohci_writel (ohci, mask, &ohci->regs->intrenable);
656 
657 	/* handle root hub init quirks ... */
658 	temp = roothub_a (ohci);
659 	temp &= ~(RH_A_PSM | RH_A_OCPM);
660 	if (ohci->flags & OHCI_QUIRK_SUPERIO) {
661 		/* NSC 87560 and maybe others */
662 		temp |= RH_A_NOCP;
663 		temp &= ~(RH_A_POTPGT | RH_A_NPS);
664 		ohci_writel (ohci, temp, &ohci->regs->roothub.a);
665 	} else if ((ohci->flags & OHCI_QUIRK_AMD756) || distrust_firmware) {
666 		/* hub power always on; required for AMD-756 and some
667 		 * Mac platforms.  ganged overcurrent reporting, if any.
668 		 */
669 		temp |= RH_A_NPS;
670 		ohci_writel (ohci, temp, &ohci->regs->roothub.a);
671 	}
672 	ohci_writel (ohci, RH_HS_LPSC, &ohci->regs->roothub.status);
673 	ohci_writel (ohci, (temp & RH_A_NPS) ? 0 : RH_B_PPCM,
674 						&ohci->regs->roothub.b);
675 	// flush those writes
676 	(void) ohci_readl (ohci, &ohci->regs->control);
677 
678 	ohci->next_statechange = jiffies + STATECHANGE_DELAY;
679 	spin_unlock_irq (&ohci->lock);
680 
681 	// POTPGT delay is bits 24-31, in 2 ms units.
682 	mdelay ((temp >> 23) & 0x1fe);
683 	hcd->state = HC_STATE_RUNNING;
684 
685 	ohci_dump (ohci, 1);
686 
687 	return 0;
688 }
689 
690 /*-------------------------------------------------------------------------*/
691 
692 /* an interrupt happens */
693 
694 static irqreturn_t ohci_irq (struct usb_hcd *hcd)
695 {
696 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
697 	struct ohci_regs __iomem *regs = ohci->regs;
698  	int			ints;
699 
700 	/* we can eliminate a (slow) ohci_readl()
701 	   if _only_ WDH caused this irq */
702 	if ((ohci->hcca->done_head != 0)
703 			&& ! (hc32_to_cpup (ohci, &ohci->hcca->done_head)
704 				& 0x01)) {
705 		ints =  OHCI_INTR_WDH;
706 
707 	/* cardbus/... hardware gone before remove() */
708 	} else if ((ints = ohci_readl (ohci, &regs->intrstatus)) == ~(u32)0) {
709 		disable (ohci);
710 		ohci_dbg (ohci, "device removed!\n");
711 		return IRQ_HANDLED;
712 
713 	/* interrupt for some other device? */
714 	} else if ((ints &= ohci_readl (ohci, &regs->intrenable)) == 0) {
715 		return IRQ_NOTMINE;
716 	}
717 
718 	if (ints & OHCI_INTR_UE) {
719 		disable (ohci);
720 		ohci_err (ohci, "OHCI Unrecoverable Error, disabled\n");
721 		// e.g. due to PCI Master/Target Abort
722 
723 		ohci_dump (ohci, 1);
724 		ohci_usb_reset (ohci);
725 	}
726 
727 	if (ints & OHCI_INTR_RHSC) {
728 		ohci_vdbg(ohci, "rhsc\n");
729 		ohci->next_statechange = jiffies + STATECHANGE_DELAY;
730 		ohci_writel(ohci, OHCI_INTR_RD | OHCI_INTR_RHSC,
731 				&regs->intrstatus);
732 		usb_hcd_poll_rh_status(hcd);
733 	}
734 
735 	/* For connect and disconnect events, we expect the controller
736 	 * to turn on RHSC along with RD.  But for remote wakeup events
737 	 * this might not happen.
738 	 */
739 	else if (ints & OHCI_INTR_RD) {
740 		ohci_vdbg(ohci, "resume detect\n");
741 		ohci_writel(ohci, OHCI_INTR_RD, &regs->intrstatus);
742 		hcd->poll_rh = 1;
743 		if (ohci->autostop) {
744 			spin_lock (&ohci->lock);
745 			ohci_rh_resume (ohci);
746 			spin_unlock (&ohci->lock);
747 		} else
748 			usb_hcd_resume_root_hub(hcd);
749 	}
750 
751 	if (ints & OHCI_INTR_WDH) {
752 		if (HC_IS_RUNNING(hcd->state))
753 			ohci_writel (ohci, OHCI_INTR_WDH, &regs->intrdisable);
754 		spin_lock (&ohci->lock);
755 		dl_done_list (ohci);
756 		spin_unlock (&ohci->lock);
757 		if (HC_IS_RUNNING(hcd->state))
758 			ohci_writel (ohci, OHCI_INTR_WDH, &regs->intrenable);
759 	}
760 
761 	/* could track INTR_SO to reduce available PCI/... bandwidth */
762 
763 	/* handle any pending URB/ED unlinks, leaving INTR_SF enabled
764 	 * when there's still unlinking to be done (next frame).
765 	 */
766 	spin_lock (&ohci->lock);
767 	if (ohci->ed_rm_list)
768 		finish_unlinks (ohci, ohci_frame_no(ohci));
769 	if ((ints & OHCI_INTR_SF) != 0 && !ohci->ed_rm_list
770 			&& HC_IS_RUNNING(hcd->state))
771 		ohci_writel (ohci, OHCI_INTR_SF, &regs->intrdisable);
772 	spin_unlock (&ohci->lock);
773 
774 	if (HC_IS_RUNNING(hcd->state)) {
775 		ohci_writel (ohci, ints, &regs->intrstatus);
776 		ohci_writel (ohci, OHCI_INTR_MIE, &regs->intrenable);
777 		// flush those writes
778 		(void) ohci_readl (ohci, &ohci->regs->control);
779 	}
780 
781 	return IRQ_HANDLED;
782 }
783 
784 /*-------------------------------------------------------------------------*/
785 
786 static void ohci_stop (struct usb_hcd *hcd)
787 {
788 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
789 
790 	ohci_dbg (ohci, "stop %s controller (state 0x%02x)\n",
791 		hcfs2string (ohci->hc_control & OHCI_CTRL_HCFS),
792 		hcd->state);
793 	ohci_dump (ohci, 1);
794 
795 	flush_scheduled_work();
796 
797 	ohci_usb_reset (ohci);
798 	ohci_writel (ohci, OHCI_INTR_MIE, &ohci->regs->intrdisable);
799 	free_irq(hcd->irq, hcd);
800 	hcd->irq = -1;
801 
802 	remove_debug_files (ohci);
803 	ohci_mem_cleanup (ohci);
804 	if (ohci->hcca) {
805 		dma_free_coherent (hcd->self.controller,
806 				sizeof *ohci->hcca,
807 				ohci->hcca, ohci->hcca_dma);
808 		ohci->hcca = NULL;
809 		ohci->hcca_dma = 0;
810 	}
811 }
812 
813 /*-------------------------------------------------------------------------*/
814 
815 /* must not be called from interrupt context */
816 
817 #ifdef	CONFIG_PM
818 
819 static int ohci_restart (struct ohci_hcd *ohci)
820 {
821 	int temp;
822 	int i;
823 	struct urb_priv *priv;
824 
825 	/* mark any devices gone, so they do nothing till khubd disconnects.
826 	 * recycle any "live" eds/tds (and urbs) right away.
827 	 * later, khubd disconnect processing will recycle the other state,
828 	 * (either as disconnect/reconnect, or maybe someday as a reset).
829 	 */
830 	spin_lock_irq(&ohci->lock);
831 	disable (ohci);
832 	usb_root_hub_lost_power(ohci_to_hcd(ohci)->self.root_hub);
833 	if (!list_empty (&ohci->pending))
834 		ohci_dbg(ohci, "abort schedule...\n");
835 	list_for_each_entry (priv, &ohci->pending, pending) {
836 		struct urb	*urb = priv->td[0]->urb;
837 		struct ed	*ed = priv->ed;
838 
839 		switch (ed->state) {
840 		case ED_OPER:
841 			ed->state = ED_UNLINK;
842 			ed->hwINFO |= cpu_to_hc32(ohci, ED_DEQUEUE);
843 			ed_deschedule (ohci, ed);
844 
845 			ed->ed_next = ohci->ed_rm_list;
846 			ed->ed_prev = NULL;
847 			ohci->ed_rm_list = ed;
848 			/* FALLTHROUGH */
849 		case ED_UNLINK:
850 			break;
851 		default:
852 			ohci_dbg(ohci, "bogus ed %p state %d\n",
853 					ed, ed->state);
854 		}
855 
856 		spin_lock (&urb->lock);
857 		urb->status = -ESHUTDOWN;
858 		spin_unlock (&urb->lock);
859 	}
860 	finish_unlinks (ohci, 0);
861 	spin_unlock_irq(&ohci->lock);
862 
863 	/* paranoia, in case that didn't work: */
864 
865 	/* empty the interrupt branches */
866 	for (i = 0; i < NUM_INTS; i++) ohci->load [i] = 0;
867 	for (i = 0; i < NUM_INTS; i++) ohci->hcca->int_table [i] = 0;
868 
869 	/* no EDs to remove */
870 	ohci->ed_rm_list = NULL;
871 
872 	/* empty control and bulk lists */
873 	ohci->ed_controltail = NULL;
874 	ohci->ed_bulktail    = NULL;
875 
876 	if ((temp = ohci_run (ohci)) < 0) {
877 		ohci_err (ohci, "can't restart, %d\n", temp);
878 		return temp;
879 	} else {
880 		/* here we "know" root ports should always stay powered,
881 		 * and that if we try to turn them back on the root hub
882 		 * will respond to CSC processing.
883 		 */
884 		i = ohci->num_ports;
885 		while (i--)
886 			ohci_writel (ohci, RH_PS_PSS,
887 				&ohci->regs->roothub.portstatus [i]);
888 		ohci_dbg (ohci, "restart complete\n");
889 	}
890 	return 0;
891 }
892 #endif
893 
894 /*-------------------------------------------------------------------------*/
895 
896 #define DRIVER_INFO DRIVER_VERSION " " DRIVER_DESC
897 
898 MODULE_AUTHOR (DRIVER_AUTHOR);
899 MODULE_DESCRIPTION (DRIVER_INFO);
900 MODULE_LICENSE ("GPL");
901 
902 #ifdef CONFIG_PCI
903 #include "ohci-pci.c"
904 #endif
905 
906 #ifdef CONFIG_SA1111
907 #include "ohci-sa1111.c"
908 #endif
909 
910 #ifdef CONFIG_ARCH_S3C2410
911 #include "ohci-s3c2410.c"
912 #endif
913 
914 #ifdef CONFIG_ARCH_OMAP
915 #include "ohci-omap.c"
916 #endif
917 
918 #ifdef CONFIG_ARCH_LH7A404
919 #include "ohci-lh7a404.c"
920 #endif
921 
922 #ifdef CONFIG_PXA27x
923 #include "ohci-pxa27x.c"
924 #endif
925 
926 #ifdef CONFIG_ARCH_EP93XX
927 #include "ohci-ep93xx.c"
928 #endif
929 
930 #ifdef CONFIG_SOC_AU1X00
931 #include "ohci-au1xxx.c"
932 #endif
933 
934 #ifdef CONFIG_USB_OHCI_HCD_PPC_SOC
935 #include "ohci-ppc-soc.c"
936 #endif
937 
938 #if defined(CONFIG_ARCH_AT91RM9200) || defined(CONFIG_ARCH_AT91SAM9261)
939 #include "ohci-at91.c"
940 #endif
941 
942 #ifdef CONFIG_ARCH_PNX4008
943 #include "ohci-pnx4008.c"
944 #endif
945 
946 #if !(defined(CONFIG_PCI) \
947       || defined(CONFIG_SA1111) \
948       || defined(CONFIG_ARCH_S3C2410) \
949       || defined(CONFIG_ARCH_OMAP) \
950       || defined (CONFIG_ARCH_LH7A404) \
951       || defined (CONFIG_PXA27x) \
952       || defined (CONFIG_ARCH_EP93XX) \
953       || defined (CONFIG_SOC_AU1X00) \
954       || defined (CONFIG_USB_OHCI_HCD_PPC_SOC) \
955       || defined (CONFIG_ARCH_AT91RM9200) \
956       || defined (CONFIG_ARCH_AT91SAM9261) \
957       || defined (CONFIG_ARCH_PNX4008) \
958 	)
959 #error "missing bus glue for ohci-hcd"
960 #endif
961