1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Enhanced Host Controller Interface (EHCI) driver for USB.
4  *
5  * Maintainer: Alan Stern <stern@rowland.harvard.edu>
6  *
7  * Copyright (c) 2000-2004 by David Brownell
8  */
9 
10 #include <linux/module.h>
11 #include <linux/pci.h>
12 #include <linux/dmapool.h>
13 #include <linux/kernel.h>
14 #include <linux/delay.h>
15 #include <linux/ioport.h>
16 #include <linux/sched.h>
17 #include <linux/vmalloc.h>
18 #include <linux/errno.h>
19 #include <linux/init.h>
20 #include <linux/hrtimer.h>
21 #include <linux/list.h>
22 #include <linux/interrupt.h>
23 #include <linux/usb.h>
24 #include <linux/usb/hcd.h>
25 #include <linux/usb/otg.h>
26 #include <linux/moduleparam.h>
27 #include <linux/dma-mapping.h>
28 #include <linux/debugfs.h>
29 #include <linux/platform_device.h>
30 #include <linux/slab.h>
31 
32 #include <asm/byteorder.h>
33 #include <asm/io.h>
34 #include <asm/irq.h>
35 #include <linux/unaligned.h>
36 
37 #if defined(CONFIG_PPC_PS3)
38 #include <asm/firmware.h>
39 #endif
40 
41 /*-------------------------------------------------------------------------*/
42 
43 /*
44  * EHCI hc_driver implementation ... experimental, incomplete.
45  * Based on the final 1.0 register interface specification.
46  *
47  * USB 2.0 shows up in upcoming www.pcmcia.org technology.
48  * First was PCMCIA, like ISA; then CardBus, which is PCI.
49  * Next comes "CardBay", using USB 2.0 signals.
50  *
51  * Contains additional contributions by Brad Hards, Rory Bolt, and others.
52  * Special thanks to Intel and VIA for providing host controllers to
53  * test this driver on, and Cypress (including In-System Design) for
54  * providing early devices for those host controllers to talk to!
55  */
56 
57 #define DRIVER_AUTHOR "David Brownell"
58 #define DRIVER_DESC "USB 2.0 'Enhanced' Host Controller (EHCI) Driver"
59 
60 static const char	hcd_name [] = "ehci_hcd";
61 
62 
63 #undef EHCI_URB_TRACE
64 
65 /* magic numbers that can affect system performance */
66 #define	EHCI_TUNE_CERR		3	/* 0-3 qtd retries; 0 == don't stop */
67 #define	EHCI_TUNE_RL_HS		4	/* nak throttle; see 4.9 */
68 #define	EHCI_TUNE_RL_TT		0
69 #define	EHCI_TUNE_MULT_HS	1	/* 1-3 transactions/uframe; 4.10.3 */
70 #define	EHCI_TUNE_MULT_TT	1
71 /*
72  * Some drivers think it's safe to schedule isochronous transfers more than
73  * 256 ms into the future (partly as a result of an old bug in the scheduling
74  * code).  In an attempt to avoid trouble, we will use a minimum scheduling
75  * length of 512 frames instead of 256.
76  */
77 #define	EHCI_TUNE_FLS		1	/* (medium) 512-frame schedule */
78 
79 /* Initial IRQ latency:  faster than hw default */
80 static int log2_irq_thresh;		// 0 to 6
81 module_param (log2_irq_thresh, int, S_IRUGO);
82 MODULE_PARM_DESC (log2_irq_thresh, "log2 IRQ latency, 1-64 microframes");
83 
84 /* initial park setting:  slower than hw default */
85 static unsigned park;
86 module_param (park, uint, S_IRUGO);
87 MODULE_PARM_DESC (park, "park setting; 1-3 back-to-back async packets");
88 
89 /* for flakey hardware, ignore overcurrent indicators */
90 static bool ignore_oc;
91 module_param (ignore_oc, bool, S_IRUGO);
92 MODULE_PARM_DESC (ignore_oc, "ignore bogus hardware overcurrent indications");
93 
94 #define	INTR_MASK (STS_IAA | STS_FATAL | STS_PCD | STS_ERR | STS_INT)
95 
96 /*-------------------------------------------------------------------------*/
97 
98 #include "ehci.h"
99 #include "pci-quirks.h"
100 
101 static void compute_tt_budget(u8 budget_table[EHCI_BANDWIDTH_SIZE],
102 		struct ehci_tt *tt);
103 
104 /*
105  * The MosChip MCS9990 controller updates its microframe counter
106  * a little before the frame counter, and occasionally we will read
107  * the invalid intermediate value.  Avoid problems by checking the
108  * microframe number (the low-order 3 bits); if they are 0 then
109  * re-read the register to get the correct value.
110  */
111 static unsigned ehci_moschip_read_frame_index(struct ehci_hcd *ehci)
112 {
113 	unsigned uf;
114 
115 	uf = ehci_readl(ehci, &ehci->regs->frame_index);
116 	if (unlikely((uf & 7) == 0))
117 		uf = ehci_readl(ehci, &ehci->regs->frame_index);
118 	return uf;
119 }
120 
121 static inline unsigned ehci_read_frame_index(struct ehci_hcd *ehci)
122 {
123 	if (ehci->frame_index_bug)
124 		return ehci_moschip_read_frame_index(ehci);
125 	return ehci_readl(ehci, &ehci->regs->frame_index);
126 }
127 
128 #include "ehci-dbg.c"
129 
130 /*-------------------------------------------------------------------------*/
131 
132 /*
133  * ehci_handshake - spin reading hc until handshake completes or fails
134  * @ptr: address of hc register to be read
135  * @mask: bits to look at in result of read
136  * @done: value of those bits when handshake succeeds
137  * @usec: timeout in microseconds
138  *
139  * Returns negative errno, or zero on success
140  *
141  * Success happens when the "mask" bits have the specified value (hardware
142  * handshake done).  There are two failure modes:  "usec" have passed (major
143  * hardware flakeout), or the register reads as all-ones (hardware removed).
144  *
145  * That last failure should_only happen in cases like physical cardbus eject
146  * before driver shutdown. But it also seems to be caused by bugs in cardbus
147  * bridge shutdown:  shutting down the bridge before the devices using it.
148  */
149 int ehci_handshake(struct ehci_hcd *ehci, void __iomem *ptr,
150 		   u32 mask, u32 done, int usec)
151 {
152 	u32	result;
153 
154 	do {
155 		result = ehci_readl(ehci, ptr);
156 		if (result == ~(u32)0)		/* card removed */
157 			return -ENODEV;
158 		result &= mask;
159 		if (result == done)
160 			return 0;
161 		udelay (1);
162 		usec--;
163 	} while (usec > 0);
164 	return -ETIMEDOUT;
165 }
166 EXPORT_SYMBOL_GPL(ehci_handshake);
167 
168 /* check TDI/ARC silicon is in host mode */
169 static int tdi_in_host_mode (struct ehci_hcd *ehci)
170 {
171 	u32		tmp;
172 
173 	tmp = ehci_readl(ehci, &ehci->regs->usbmode);
174 	return (tmp & 3) == USBMODE_CM_HC;
175 }
176 
177 /*
178  * Force HC to halt state from unknown (EHCI spec section 2.3).
179  * Must be called with interrupts enabled and the lock not held.
180  */
181 static int ehci_halt (struct ehci_hcd *ehci)
182 {
183 	u32	temp;
184 
185 	spin_lock_irq(&ehci->lock);
186 
187 	/* disable any irqs left enabled by previous code */
188 	ehci_writel(ehci, 0, &ehci->regs->intr_enable);
189 
190 	if (ehci_is_TDI(ehci) && !tdi_in_host_mode(ehci)) {
191 		spin_unlock_irq(&ehci->lock);
192 		return 0;
193 	}
194 
195 	/*
196 	 * This routine gets called during probe before ehci->command
197 	 * has been initialized, so we can't rely on its value.
198 	 */
199 	ehci->command &= ~CMD_RUN;
200 	temp = ehci_readl(ehci, &ehci->regs->command);
201 	temp &= ~(CMD_RUN | CMD_IAAD);
202 	ehci_writel(ehci, temp, &ehci->regs->command);
203 
204 	spin_unlock_irq(&ehci->lock);
205 	synchronize_irq(ehci_to_hcd(ehci)->irq);
206 
207 	return ehci_handshake(ehci, &ehci->regs->status,
208 			  STS_HALT, STS_HALT, 16 * 125);
209 }
210 
211 /* put TDI/ARC silicon into EHCI mode */
212 static void tdi_reset (struct ehci_hcd *ehci)
213 {
214 	u32		tmp;
215 
216 	tmp = ehci_readl(ehci, &ehci->regs->usbmode);
217 	tmp |= USBMODE_CM_HC;
218 	/* The default byte access to MMR space is LE after
219 	 * controller reset. Set the required endian mode
220 	 * for transfer buffers to match the host microprocessor
221 	 */
222 	if (ehci_big_endian_mmio(ehci))
223 		tmp |= USBMODE_BE;
224 	ehci_writel(ehci, tmp, &ehci->regs->usbmode);
225 }
226 
227 /*
228  * Reset a non-running (STS_HALT == 1) controller.
229  * Must be called with interrupts enabled and the lock not held.
230  */
231 int ehci_reset(struct ehci_hcd *ehci)
232 {
233 	int	retval;
234 	u32	command = ehci_readl(ehci, &ehci->regs->command);
235 
236 	/* If the EHCI debug controller is active, special care must be
237 	 * taken before and after a host controller reset */
238 	if (ehci->debug && !dbgp_reset_prep(ehci_to_hcd(ehci)))
239 		ehci->debug = NULL;
240 
241 	command |= CMD_RESET;
242 	dbg_cmd (ehci, "reset", command);
243 	ehci_writel(ehci, command, &ehci->regs->command);
244 	ehci->rh_state = EHCI_RH_HALTED;
245 	ehci->next_statechange = jiffies;
246 	retval = ehci_handshake(ehci, &ehci->regs->command,
247 			    CMD_RESET, 0, 250 * 1000);
248 
249 	if (ehci->has_hostpc) {
250 		ehci_writel(ehci, USBMODE_EX_HC | USBMODE_EX_VBPS,
251 				&ehci->regs->usbmode_ex);
252 		ehci_writel(ehci, TXFIFO_DEFAULT, &ehci->regs->txfill_tuning);
253 	}
254 	if (retval)
255 		return retval;
256 
257 	if (ehci_is_TDI(ehci))
258 		tdi_reset (ehci);
259 
260 	if (ehci->debug)
261 		dbgp_external_startup(ehci_to_hcd(ehci));
262 
263 	ehci->port_c_suspend = ehci->suspended_ports =
264 			ehci->resuming_ports = 0;
265 	return retval;
266 }
267 EXPORT_SYMBOL_GPL(ehci_reset);
268 
269 /*
270  * Idle the controller (turn off the schedules).
271  * Must be called with interrupts enabled and the lock not held.
272  */
273 static void ehci_quiesce (struct ehci_hcd *ehci)
274 {
275 	u32	temp;
276 
277 	if (ehci->rh_state != EHCI_RH_RUNNING)
278 		return;
279 
280 	/* wait for any schedule enables/disables to take effect */
281 	temp = (ehci->command << 10) & (STS_ASS | STS_PSS);
282 	ehci_handshake(ehci, &ehci->regs->status, STS_ASS | STS_PSS, temp,
283 			16 * 125);
284 
285 	/* then disable anything that's still active */
286 	spin_lock_irq(&ehci->lock);
287 	ehci->command &= ~(CMD_ASE | CMD_PSE);
288 	ehci_writel(ehci, ehci->command, &ehci->regs->command);
289 	spin_unlock_irq(&ehci->lock);
290 
291 	/* hardware can take 16 microframes to turn off ... */
292 	ehci_handshake(ehci, &ehci->regs->status, STS_ASS | STS_PSS, 0,
293 			16 * 125);
294 }
295 
296 /*-------------------------------------------------------------------------*/
297 
298 static void end_iaa_cycle(struct ehci_hcd *ehci);
299 static void end_unlink_async(struct ehci_hcd *ehci);
300 static void unlink_empty_async(struct ehci_hcd *ehci);
301 static void ehci_work(struct ehci_hcd *ehci);
302 static void start_unlink_intr(struct ehci_hcd *ehci, struct ehci_qh *qh);
303 static void end_unlink_intr(struct ehci_hcd *ehci, struct ehci_qh *qh);
304 static int ehci_port_power(struct ehci_hcd *ehci, int portnum, bool enable);
305 
306 #include "ehci-timer.c"
307 #include "ehci-hub.c"
308 #include "ehci-mem.c"
309 #include "ehci-q.c"
310 #include "ehci-sched.c"
311 #include "ehci-sysfs.c"
312 
313 /*-------------------------------------------------------------------------*/
314 
315 /* On some systems, leaving remote wakeup enabled prevents system shutdown.
316  * The firmware seems to think that powering off is a wakeup event!
317  * This routine turns off remote wakeup and everything else, on all ports.
318  */
319 static void ehci_turn_off_all_ports(struct ehci_hcd *ehci)
320 {
321 	int	port = HCS_N_PORTS(ehci->hcs_params);
322 
323 	while (port--) {
324 		spin_unlock_irq(&ehci->lock);
325 		ehci_port_power(ehci, port, false);
326 		spin_lock_irq(&ehci->lock);
327 		ehci_writel(ehci, PORT_RWC_BITS,
328 				&ehci->regs->port_status[port]);
329 	}
330 }
331 
332 /*
333  * Halt HC, turn off all ports, and let the BIOS use the companion controllers.
334  * Must be called with interrupts enabled and the lock not held.
335  */
336 static void ehci_silence_controller(struct ehci_hcd *ehci)
337 {
338 	ehci_halt(ehci);
339 
340 	spin_lock_irq(&ehci->lock);
341 	ehci->rh_state = EHCI_RH_HALTED;
342 	ehci_turn_off_all_ports(ehci);
343 
344 	/* make BIOS/etc use companion controller during reboot */
345 	ehci_writel(ehci, 0, &ehci->regs->configured_flag);
346 
347 	/* unblock posted writes */
348 	ehci_readl(ehci, &ehci->regs->configured_flag);
349 	spin_unlock_irq(&ehci->lock);
350 }
351 
352 /* ehci_shutdown kick in for silicon on any bus (not just pci, etc).
353  * This forcibly disables dma and IRQs, helping kexec and other cases
354  * where the next system software may expect clean state.
355  */
356 static void ehci_shutdown(struct usb_hcd *hcd)
357 {
358 	struct ehci_hcd	*ehci = hcd_to_ehci(hcd);
359 
360 	/**
361 	 * Protect the system from crashing at system shutdown in cases where
362 	 * usb host is not added yet from OTG controller driver.
363 	 * As ehci_setup() not done yet, so stop accessing registers or
364 	 * variables initialized in ehci_setup()
365 	 */
366 	if (!ehci->sbrn)
367 		return;
368 
369 	spin_lock_irq(&ehci->lock);
370 	ehci->shutdown = true;
371 	ehci->rh_state = EHCI_RH_STOPPING;
372 	ehci->enabled_hrtimer_events = 0;
373 	spin_unlock_irq(&ehci->lock);
374 
375 	ehci_silence_controller(ehci);
376 
377 	hrtimer_cancel(&ehci->hrtimer);
378 }
379 
380 /*-------------------------------------------------------------------------*/
381 
382 /*
383  * ehci_work is called from some interrupts, timers, and so on.
384  * it calls driver completion functions, after dropping ehci->lock.
385  */
386 static void ehci_work (struct ehci_hcd *ehci)
387 {
388 	/* another CPU may drop ehci->lock during a schedule scan while
389 	 * it reports urb completions.  this flag guards against bogus
390 	 * attempts at re-entrant schedule scanning.
391 	 */
392 	if (ehci->scanning) {
393 		ehci->need_rescan = true;
394 		return;
395 	}
396 	ehci->scanning = true;
397 
398  rescan:
399 	ehci->need_rescan = false;
400 	if (ehci->async_count)
401 		scan_async(ehci);
402 	if (ehci->intr_count > 0)
403 		scan_intr(ehci);
404 	if (ehci->isoc_count > 0)
405 		scan_isoc(ehci);
406 	if (ehci->need_rescan)
407 		goto rescan;
408 	ehci->scanning = false;
409 
410 	/* the IO watchdog guards against hardware or driver bugs that
411 	 * misplace IRQs, and should let us run completely without IRQs.
412 	 * such lossage has been observed on both VT6202 and VT8235.
413 	 */
414 	turn_on_io_watchdog(ehci);
415 }
416 
417 /*
418  * Called when the ehci_hcd module is removed.
419  */
420 static void ehci_stop (struct usb_hcd *hcd)
421 {
422 	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
423 
424 	ehci_dbg (ehci, "stop\n");
425 
426 	/* no more interrupts ... */
427 
428 	spin_lock_irq(&ehci->lock);
429 	ehci->enabled_hrtimer_events = 0;
430 	spin_unlock_irq(&ehci->lock);
431 
432 	ehci_quiesce(ehci);
433 	ehci_silence_controller(ehci);
434 	ehci_reset (ehci);
435 
436 	hrtimer_cancel(&ehci->hrtimer);
437 	remove_sysfs_files(ehci);
438 	remove_debug_files (ehci);
439 
440 	/* root hub is shut down separately (first, when possible) */
441 	spin_lock_irq (&ehci->lock);
442 	end_free_itds(ehci);
443 	spin_unlock_irq (&ehci->lock);
444 	ehci_mem_cleanup (ehci);
445 
446 	if (ehci->amd_pll_fix == 1)
447 		usb_amd_dev_put();
448 
449 	dbg_status (ehci, "ehci_stop completed",
450 		    ehci_readl(ehci, &ehci->regs->status));
451 }
452 
453 /* one-time init, only for memory state */
454 static int ehci_init(struct usb_hcd *hcd)
455 {
456 	struct ehci_hcd		*ehci = hcd_to_ehci(hcd);
457 	u32			temp;
458 	int			retval;
459 	u32			hcc_params;
460 	struct ehci_qh_hw	*hw;
461 
462 	spin_lock_init(&ehci->lock);
463 
464 	/*
465 	 * keep io watchdog by default, those good HCDs could turn off it later
466 	 */
467 	ehci->need_io_watchdog = 1;
468 
469 	hrtimer_setup(&ehci->hrtimer, ehci_hrtimer_func, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
470 	ehci->next_hrtimer_event = EHCI_HRTIMER_NO_EVENT;
471 
472 	hcc_params = ehci_readl(ehci, &ehci->caps->hcc_params);
473 
474 	/*
475 	 * by default set standard 80% (== 100 usec/uframe) max periodic
476 	 * bandwidth as required by USB 2.0
477 	 */
478 	ehci->uframe_periodic_max = 100;
479 
480 	/*
481 	 * hw default: 1K periodic list heads, one per frame.
482 	 * periodic_size can shrink by USBCMD update if hcc_params allows.
483 	 */
484 	ehci->periodic_size = DEFAULT_I_TDPS;
485 	INIT_LIST_HEAD(&ehci->async_unlink);
486 	INIT_LIST_HEAD(&ehci->async_idle);
487 	INIT_LIST_HEAD(&ehci->intr_unlink_wait);
488 	INIT_LIST_HEAD(&ehci->intr_unlink);
489 	INIT_LIST_HEAD(&ehci->intr_qh_list);
490 	INIT_LIST_HEAD(&ehci->cached_itd_list);
491 	INIT_LIST_HEAD(&ehci->cached_sitd_list);
492 	INIT_LIST_HEAD(&ehci->tt_list);
493 
494 	if (HCC_PGM_FRAMELISTLEN(hcc_params)) {
495 		/* periodic schedule size can be smaller than default */
496 		switch (EHCI_TUNE_FLS) {
497 		case 0: ehci->periodic_size = 1024; break;
498 		case 1: ehci->periodic_size = 512; break;
499 		case 2: ehci->periodic_size = 256; break;
500 		default:	BUG();
501 		}
502 	}
503 	if ((retval = ehci_mem_init(ehci, GFP_KERNEL)) < 0)
504 		return retval;
505 
506 	/* controllers may cache some of the periodic schedule ... */
507 	if (HCC_ISOC_CACHE(hcc_params))		// full frame cache
508 		ehci->i_thresh = 0;
509 	else					// N microframes cached
510 		ehci->i_thresh = 2 + HCC_ISOC_THRES(hcc_params);
511 
512 	/*
513 	 * dedicate a qh for the async ring head, since we couldn't unlink
514 	 * a 'real' qh without stopping the async schedule [4.8].  use it
515 	 * as the 'reclamation list head' too.
516 	 * its dummy is used in hw_alt_next of many tds, to prevent the qh
517 	 * from automatically advancing to the next td after short reads.
518 	 */
519 	ehci->async->qh_next.qh = NULL;
520 	hw = ehci->async->hw;
521 	hw->hw_next = QH_NEXT(ehci, ehci->async->qh_dma);
522 	hw->hw_info1 = cpu_to_hc32(ehci, QH_HEAD);
523 #if defined(CONFIG_PPC_PS3)
524 	hw->hw_info1 |= cpu_to_hc32(ehci, QH_INACTIVATE);
525 #endif
526 	hw->hw_token = cpu_to_hc32(ehci, QTD_STS_HALT);
527 	hw->hw_qtd_next = EHCI_LIST_END(ehci);
528 	ehci->async->qh_state = QH_STATE_LINKED;
529 	hw->hw_alt_next = QTD_NEXT(ehci, ehci->async->dummy->qtd_dma);
530 
531 	/* clear interrupt enables, set irq latency */
532 	if (log2_irq_thresh < 0 || log2_irq_thresh > 6)
533 		log2_irq_thresh = 0;
534 	temp = 1 << (16 + log2_irq_thresh);
535 	if (HCC_PER_PORT_CHANGE_EVENT(hcc_params)) {
536 		ehci->has_ppcd = 1;
537 		ehci_dbg(ehci, "enable per-port change event\n");
538 		temp |= CMD_PPCEE;
539 	}
540 	if (HCC_CANPARK(hcc_params)) {
541 		/* HW default park == 3, on hardware that supports it (like
542 		 * NVidia and ALI silicon), maximizes throughput on the async
543 		 * schedule by avoiding QH fetches between transfers.
544 		 *
545 		 * With fast usb storage devices and NForce2, "park" seems to
546 		 * make problems:  throughput reduction (!), data errors...
547 		 */
548 		if (park) {
549 			park = min_t(unsigned int, park, 3);
550 			temp |= CMD_PARK;
551 			temp |= park << 8;
552 		}
553 		ehci_dbg(ehci, "park %d\n", park);
554 	}
555 	if (HCC_PGM_FRAMELISTLEN(hcc_params)) {
556 		/* periodic schedule size can be smaller than default */
557 		temp &= ~(3 << 2);
558 		temp |= (EHCI_TUNE_FLS << 2);
559 	}
560 	ehci->command = temp;
561 
562 	/* Accept arbitrarily long scatter-gather lists */
563 	if (!hcd->localmem_pool)
564 		hcd->self.sg_tablesize = ~0;
565 
566 	/* Prepare for unlinking active QHs */
567 	ehci->old_current = ~0;
568 	return 0;
569 }
570 
571 /* start HC running; it's halted, ehci_init() has been run (once) */
572 static int ehci_run (struct usb_hcd *hcd)
573 {
574 	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
575 	u32			temp;
576 	u32			hcc_params;
577 	int			rc;
578 
579 	hcd->uses_new_polling = 1;
580 
581 	/* EHCI spec section 4.1 */
582 
583 	ehci_writel(ehci, ehci->periodic_dma, &ehci->regs->frame_list);
584 	ehci_writel(ehci, (u32)ehci->async->qh_dma, &ehci->regs->async_next);
585 
586 	/*
587 	 * hcc_params controls whether ehci->regs->segment must (!!!)
588 	 * be used; it constrains QH/ITD/SITD and QTD locations.
589 	 * dma_pool consistent memory always uses segment zero.
590 	 * streaming mappings for I/O buffers, like dma_map_single(),
591 	 * can return segments above 4GB, if the device allows.
592 	 *
593 	 * NOTE:  the dma mask is visible through dev->dma_mask, so
594 	 * drivers can pass this info along ... like NETIF_F_HIGHDMA,
595 	 * Scsi_Host.highmem_io, and so forth.  It's readonly to all
596 	 * host side drivers though.
597 	 */
598 	hcc_params = ehci_readl(ehci, &ehci->caps->hcc_params);
599 	if (HCC_64BIT_ADDR(hcc_params)) {
600 		ehci_writel(ehci, 0, &ehci->regs->segment);
601 #if 0
602 // this is deeply broken on almost all architectures
603 		if (!dma_set_mask(hcd->self.controller, DMA_BIT_MASK(64)))
604 			ehci_info(ehci, "enabled 64bit DMA\n");
605 #endif
606 	}
607 
608 
609 	// Philips, Intel, and maybe others need CMD_RUN before the
610 	// root hub will detect new devices (why?); NEC doesn't
611 	ehci->command &= ~(CMD_LRESET|CMD_IAAD|CMD_PSE|CMD_ASE|CMD_RESET);
612 	ehci->command |= CMD_RUN;
613 	ehci_writel(ehci, ehci->command, &ehci->regs->command);
614 	dbg_cmd (ehci, "init", ehci->command);
615 
616 	/*
617 	 * Start, enabling full USB 2.0 functionality ... usb 1.1 devices
618 	 * are explicitly handed to companion controller(s), so no TT is
619 	 * involved with the root hub.  (Except where one is integrated,
620 	 * and there's no companion controller unless maybe for USB OTG.)
621 	 *
622 	 * Turning on the CF flag will transfer ownership of all ports
623 	 * from the companions to the EHCI controller.  If any of the
624 	 * companions are in the middle of a port reset at the time, it
625 	 * could cause trouble.  Write-locking ehci_cf_port_reset_rwsem
626 	 * guarantees that no resets are in progress.  After we set CF,
627 	 * a short delay lets the hardware catch up; new resets shouldn't
628 	 * be started before the port switching actions could complete.
629 	 */
630 	down_write(&ehci_cf_port_reset_rwsem);
631 	ehci->rh_state = EHCI_RH_RUNNING;
632 	ehci_writel(ehci, FLAG_CF, &ehci->regs->configured_flag);
633 
634 	/* Wait until HC become operational */
635 	ehci_readl(ehci, &ehci->regs->command);	/* unblock posted writes */
636 	msleep(5);
637 
638 	/* For Aspeed, STS_HALT also depends on ASS/PSS status.
639 	 * Check CMD_RUN instead.
640 	 */
641 	if (ehci->is_aspeed)
642 		rc = ehci_handshake(ehci, &ehci->regs->command, CMD_RUN,
643 				    1, 100 * 1000);
644 	else
645 		rc = ehci_handshake(ehci, &ehci->regs->status, STS_HALT,
646 				    0, 100 * 1000);
647 
648 	up_write(&ehci_cf_port_reset_rwsem);
649 
650 	if (rc) {
651 		ehci_err(ehci, "USB %x.%x, controller refused to start: %d\n",
652 			 ((ehci->sbrn & 0xf0)>>4), (ehci->sbrn & 0x0f), rc);
653 		return rc;
654 	}
655 
656 	ehci->last_periodic_enable = ktime_get_real();
657 
658 	temp = HC_VERSION(ehci, ehci_readl(ehci, &ehci->caps->hc_capbase));
659 	ehci_info (ehci,
660 		"USB %x.%x started, EHCI %x.%02x%s\n",
661 		((ehci->sbrn & 0xf0)>>4), (ehci->sbrn & 0x0f),
662 		temp >> 8, temp & 0xff,
663 		(ignore_oc || ehci->spurious_oc) ? ", overcurrent ignored" : "");
664 
665 	ehci_writel(ehci, INTR_MASK,
666 		    &ehci->regs->intr_enable); /* Turn On Interrupts */
667 
668 	/* GRR this is run-once init(), being done every time the HC starts.
669 	 * So long as they're part of class devices, we can't do it init()
670 	 * since the class device isn't created that early.
671 	 */
672 	create_debug_files(ehci);
673 	create_sysfs_files(ehci);
674 
675 	return 0;
676 }
677 
678 int ehci_setup(struct usb_hcd *hcd)
679 {
680 	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
681 	int retval;
682 
683 	ehci->regs = (void __iomem *)ehci->caps +
684 	    HC_LENGTH(ehci, ehci_readl(ehci, &ehci->caps->hc_capbase));
685 	dbg_hcs_params(ehci, "reset");
686 	dbg_hcc_params(ehci, "reset");
687 
688 	/* cache this readonly data; minimize chip reads */
689 	ehci->hcs_params = ehci_readl(ehci, &ehci->caps->hcs_params);
690 
691 	ehci->sbrn = HCD_USB2;
692 
693 	/* data structure init */
694 	retval = ehci_init(hcd);
695 	if (retval)
696 		return retval;
697 
698 	retval = ehci_halt(ehci);
699 	if (retval) {
700 		ehci_mem_cleanup(ehci);
701 		return retval;
702 	}
703 
704 	ehci_reset(ehci);
705 
706 	return 0;
707 }
708 EXPORT_SYMBOL_GPL(ehci_setup);
709 
710 /*-------------------------------------------------------------------------*/
711 
712 static irqreturn_t ehci_irq (struct usb_hcd *hcd)
713 {
714 	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
715 	u32			status, current_status, masked_status, pcd_status = 0;
716 	u32			cmd;
717 	int			bh;
718 
719 	spin_lock(&ehci->lock);
720 
721 	status = 0;
722 	current_status = ehci_readl(ehci, &ehci->regs->status);
723 restart:
724 
725 	/* e.g. cardbus physical eject */
726 	if (current_status == ~(u32) 0) {
727 		ehci_dbg (ehci, "device removed\n");
728 		goto dead;
729 	}
730 	status |= current_status;
731 
732 	/*
733 	 * We don't use STS_FLR, but some controllers don't like it to
734 	 * remain on, so mask it out along with the other status bits.
735 	 */
736 	masked_status = current_status & (INTR_MASK | STS_FLR);
737 
738 	/* Shared IRQ? */
739 	if (!masked_status || unlikely(ehci->rh_state == EHCI_RH_HALTED)) {
740 		spin_unlock(&ehci->lock);
741 		return IRQ_NONE;
742 	}
743 
744 	/* clear (just) interrupts */
745 	ehci_writel(ehci, masked_status, &ehci->regs->status);
746 
747 	/* For edge interrupts, don't race with an interrupt bit being raised */
748 	current_status = ehci_readl(ehci, &ehci->regs->status);
749 	if (current_status & INTR_MASK)
750 		goto restart;
751 
752 	cmd = ehci_readl(ehci, &ehci->regs->command);
753 	bh = 0;
754 
755 	/* normal [4.15.1.2] or error [4.15.1.1] completion */
756 	if (likely ((status & (STS_INT|STS_ERR)) != 0)) {
757 		if (likely ((status & STS_ERR) == 0)) {
758 			INCR(ehci->stats.normal);
759 		} else {
760 			/* Force to check port status */
761 			if (ehci->has_ci_pec_bug)
762 				status |= STS_PCD;
763 			INCR(ehci->stats.error);
764 		}
765 		bh = 1;
766 	}
767 
768 	/* complete the unlinking of some qh [4.15.2.3] */
769 	if (status & STS_IAA) {
770 
771 		/* Turn off the IAA watchdog */
772 		ehci->enabled_hrtimer_events &= ~BIT(EHCI_HRTIMER_IAA_WATCHDOG);
773 
774 		/*
775 		 * Mild optimization: Allow another IAAD to reset the
776 		 * hrtimer, if one occurs before the next expiration.
777 		 * In theory we could always cancel the hrtimer, but
778 		 * tests show that about half the time it will be reset
779 		 * for some other event anyway.
780 		 */
781 		if (ehci->next_hrtimer_event == EHCI_HRTIMER_IAA_WATCHDOG)
782 			++ehci->next_hrtimer_event;
783 
784 		/* guard against (alleged) silicon errata */
785 		if (cmd & CMD_IAAD)
786 			ehci_dbg(ehci, "IAA with IAAD still set?\n");
787 		if (ehci->iaa_in_progress)
788 			INCR(ehci->stats.iaa);
789 		end_iaa_cycle(ehci);
790 	}
791 
792 	/* remote wakeup [4.3.1] */
793 	if (status & STS_PCD) {
794 		unsigned	i = HCS_N_PORTS (ehci->hcs_params);
795 		u32		ppcd = ~0;
796 
797 		/* kick root hub later */
798 		pcd_status = status;
799 
800 		/* resume root hub? */
801 		if (ehci->rh_state == EHCI_RH_SUSPENDED)
802 			usb_hcd_resume_root_hub(hcd);
803 
804 		/* get per-port change detect bits */
805 		if (ehci->has_ppcd)
806 			ppcd = status >> 16;
807 
808 		while (i--) {
809 			int pstatus;
810 
811 			/* leverage per-port change bits feature */
812 			if (!(ppcd & (1 << i)))
813 				continue;
814 			pstatus = ehci_readl(ehci,
815 					 &ehci->regs->port_status[i]);
816 
817 			if (pstatus & PORT_OWNER)
818 				continue;
819 			if (!(test_bit(i, &ehci->suspended_ports) &&
820 					((pstatus & PORT_RESUME) ||
821 						!(pstatus & PORT_SUSPEND)) &&
822 					(pstatus & PORT_PE) &&
823 					ehci->reset_done[i] == 0))
824 				continue;
825 
826 			/* start USB_RESUME_TIMEOUT msec resume signaling from
827 			 * this port, and make hub_wq collect
828 			 * PORT_STAT_C_SUSPEND to stop that signaling.
829 			 */
830 			ehci->reset_done[i] = jiffies +
831 				msecs_to_jiffies(USB_RESUME_TIMEOUT);
832 			set_bit(i, &ehci->resuming_ports);
833 			ehci_dbg (ehci, "port %d remote wakeup\n", i + 1);
834 			usb_hcd_start_port_resume(&hcd->self, i);
835 			mod_timer(&hcd->rh_timer, ehci->reset_done[i]);
836 		}
837 	}
838 
839 	/* PCI errors [4.15.2.4] */
840 	if (unlikely ((status & STS_FATAL) != 0)) {
841 		ehci_err(ehci, "fatal error\n");
842 		dbg_cmd(ehci, "fatal", cmd);
843 		dbg_status(ehci, "fatal", status);
844 dead:
845 		usb_hc_died(hcd);
846 
847 		/* Don't let the controller do anything more */
848 		ehci->shutdown = true;
849 		ehci->rh_state = EHCI_RH_STOPPING;
850 		ehci->command &= ~(CMD_RUN | CMD_ASE | CMD_PSE);
851 		ehci_writel(ehci, ehci->command, &ehci->regs->command);
852 		ehci_writel(ehci, 0, &ehci->regs->intr_enable);
853 		ehci_handle_controller_death(ehci);
854 
855 		/* Handle completions when the controller stops */
856 		bh = 0;
857 	}
858 
859 	if (bh)
860 		ehci_work (ehci);
861 	spin_unlock(&ehci->lock);
862 	if (pcd_status)
863 		usb_hcd_poll_rh_status(hcd);
864 	return IRQ_HANDLED;
865 }
866 
867 /*-------------------------------------------------------------------------*/
868 
869 /*
870  * non-error returns are a promise to giveback() the urb later
871  * we drop ownership so next owner (or urb unlink) can get it
872  *
873  * urb + dev is in hcd.self.controller.urb_list
874  * we're queueing TDs onto software and hardware lists
875  *
876  * hcd-specific init for hcpriv hasn't been done yet
877  *
878  * NOTE:  control, bulk, and interrupt share the same code to append TDs
879  * to a (possibly active) QH, and the same QH scanning code.
880  */
881 static int ehci_urb_enqueue (
882 	struct usb_hcd	*hcd,
883 	struct urb	*urb,
884 	gfp_t		mem_flags
885 ) {
886 	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
887 	struct list_head	qtd_list;
888 
889 	INIT_LIST_HEAD (&qtd_list);
890 
891 	switch (usb_pipetype (urb->pipe)) {
892 	case PIPE_CONTROL:
893 		/* qh_completions() code doesn't handle all the fault cases
894 		 * in multi-TD control transfers.  Even 1KB is rare anyway.
895 		 */
896 		if (urb->transfer_buffer_length > (16 * 1024))
897 			return -EMSGSIZE;
898 		fallthrough;
899 	/* case PIPE_BULK: */
900 	default:
901 		if (!qh_urb_transaction (ehci, urb, &qtd_list, mem_flags))
902 			return -ENOMEM;
903 		return submit_async(ehci, urb, &qtd_list, mem_flags);
904 
905 	case PIPE_INTERRUPT:
906 		if (!qh_urb_transaction (ehci, urb, &qtd_list, mem_flags))
907 			return -ENOMEM;
908 		return intr_submit(ehci, urb, &qtd_list, mem_flags);
909 
910 	case PIPE_ISOCHRONOUS:
911 		if (urb->dev->speed == USB_SPEED_HIGH)
912 			return itd_submit (ehci, urb, mem_flags);
913 		else
914 			return sitd_submit (ehci, urb, mem_flags);
915 	}
916 }
917 
918 /* remove from hardware lists
919  * completions normally happen asynchronously
920  */
921 
922 static int ehci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
923 {
924 	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
925 	struct ehci_qh		*qh;
926 	unsigned long		flags;
927 	int			rc;
928 
929 	spin_lock_irqsave (&ehci->lock, flags);
930 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
931 	if (rc)
932 		goto done;
933 
934 	if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) {
935 		/*
936 		 * We don't expedite dequeue for isochronous URBs.
937 		 * Just wait until they complete normally or their
938 		 * time slot expires.
939 		 */
940 	} else {
941 		qh = (struct ehci_qh *) urb->hcpriv;
942 		qh->unlink_reason |= QH_UNLINK_REQUESTED;
943 		switch (qh->qh_state) {
944 		case QH_STATE_LINKED:
945 			if (usb_pipetype(urb->pipe) == PIPE_INTERRUPT)
946 				start_unlink_intr(ehci, qh);
947 			else
948 				start_unlink_async(ehci, qh);
949 			break;
950 		case QH_STATE_COMPLETING:
951 			qh->dequeue_during_giveback = 1;
952 			break;
953 		case QH_STATE_UNLINK:
954 		case QH_STATE_UNLINK_WAIT:
955 			/* already started */
956 			break;
957 		case QH_STATE_IDLE:
958 			/* QH might be waiting for a Clear-TT-Buffer */
959 			qh_completions(ehci, qh);
960 			break;
961 		}
962 	}
963 done:
964 	spin_unlock_irqrestore (&ehci->lock, flags);
965 	return rc;
966 }
967 
968 /*-------------------------------------------------------------------------*/
969 
970 // bulk qh holds the data toggle
971 
972 static void
973 ehci_endpoint_disable (struct usb_hcd *hcd, struct usb_host_endpoint *ep)
974 {
975 	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
976 	unsigned long		flags;
977 	struct ehci_qh		*qh;
978 
979 	/* ASSERT:  any requests/urbs are being unlinked */
980 	/* ASSERT:  nobody can be submitting urbs for this any more */
981 
982 rescan:
983 	spin_lock_irqsave (&ehci->lock, flags);
984 	qh = ep->hcpriv;
985 	if (!qh)
986 		goto done;
987 
988 	/* endpoints can be iso streams.  for now, we don't
989 	 * accelerate iso completions ... so spin a while.
990 	 */
991 	if (qh->hw == NULL) {
992 		struct ehci_iso_stream	*stream = ep->hcpriv;
993 
994 		if (!list_empty(&stream->td_list))
995 			goto idle_timeout;
996 
997 		/* BUG_ON(!list_empty(&stream->free_list)); */
998 		reserve_release_iso_bandwidth(ehci, stream, -1);
999 		kfree(stream);
1000 		goto done;
1001 	}
1002 
1003 	qh->unlink_reason |= QH_UNLINK_REQUESTED;
1004 	switch (qh->qh_state) {
1005 	case QH_STATE_LINKED:
1006 		if (list_empty(&qh->qtd_list))
1007 			qh->unlink_reason |= QH_UNLINK_QUEUE_EMPTY;
1008 		else
1009 			WARN_ON(1);
1010 		if (usb_endpoint_type(&ep->desc) != USB_ENDPOINT_XFER_INT)
1011 			start_unlink_async(ehci, qh);
1012 		else
1013 			start_unlink_intr(ehci, qh);
1014 		fallthrough;
1015 	case QH_STATE_COMPLETING:	/* already in unlinking */
1016 	case QH_STATE_UNLINK:		/* wait for hw to finish? */
1017 	case QH_STATE_UNLINK_WAIT:
1018 idle_timeout:
1019 		spin_unlock_irqrestore (&ehci->lock, flags);
1020 		schedule_timeout_uninterruptible(1);
1021 		goto rescan;
1022 	case QH_STATE_IDLE:		/* fully unlinked */
1023 		if (qh->clearing_tt)
1024 			goto idle_timeout;
1025 		if (list_empty (&qh->qtd_list)) {
1026 			if (qh->ps.bw_uperiod)
1027 				reserve_release_intr_bandwidth(ehci, qh, -1);
1028 			qh_destroy(ehci, qh);
1029 			break;
1030 		}
1031 		fallthrough;
1032 	default:
1033 		/* caller was supposed to have unlinked any requests;
1034 		 * that's not our job.  just leak this memory.
1035 		 */
1036 		ehci_err (ehci, "qh %p (#%02x) state %d%s\n",
1037 			qh, ep->desc.bEndpointAddress, qh->qh_state,
1038 			list_empty (&qh->qtd_list) ? "" : "(has tds)");
1039 		break;
1040 	}
1041  done:
1042 	ep->hcpriv = NULL;
1043 	spin_unlock_irqrestore (&ehci->lock, flags);
1044 }
1045 
1046 static void
1047 ehci_endpoint_reset(struct usb_hcd *hcd, struct usb_host_endpoint *ep)
1048 {
1049 	struct ehci_hcd		*ehci = hcd_to_ehci(hcd);
1050 	struct ehci_qh		*qh;
1051 	int			eptype = usb_endpoint_type(&ep->desc);
1052 	int			epnum = usb_endpoint_num(&ep->desc);
1053 	int			is_out = usb_endpoint_dir_out(&ep->desc);
1054 	unsigned long		flags;
1055 
1056 	if (eptype != USB_ENDPOINT_XFER_BULK && eptype != USB_ENDPOINT_XFER_INT)
1057 		return;
1058 
1059 	spin_lock_irqsave(&ehci->lock, flags);
1060 	qh = ep->hcpriv;
1061 
1062 	/* For Bulk and Interrupt endpoints we maintain the toggle state
1063 	 * in the hardware; the toggle bits in udev aren't used at all.
1064 	 * When an endpoint is reset by usb_clear_halt() we must reset
1065 	 * the toggle bit in the QH.
1066 	 */
1067 	if (qh) {
1068 		if (!list_empty(&qh->qtd_list)) {
1069 			WARN_ONCE(1, "clear_halt for a busy endpoint\n");
1070 		} else {
1071 			/* The toggle value in the QH can't be updated
1072 			 * while the QH is active.  Unlink it now;
1073 			 * re-linking will call qh_refresh().
1074 			 */
1075 			usb_settoggle(qh->ps.udev, epnum, is_out, 0);
1076 			qh->unlink_reason |= QH_UNLINK_REQUESTED;
1077 			if (eptype == USB_ENDPOINT_XFER_BULK)
1078 				start_unlink_async(ehci, qh);
1079 			else
1080 				start_unlink_intr(ehci, qh);
1081 		}
1082 	}
1083 	spin_unlock_irqrestore(&ehci->lock, flags);
1084 }
1085 
1086 static int ehci_get_frame (struct usb_hcd *hcd)
1087 {
1088 	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
1089 	return (ehci_read_frame_index(ehci) >> 3) % ehci->periodic_size;
1090 }
1091 
1092 /*-------------------------------------------------------------------------*/
1093 
1094 /* Device addition and removal */
1095 
1096 static void ehci_remove_device(struct usb_hcd *hcd, struct usb_device *udev)
1097 {
1098 	struct ehci_hcd		*ehci = hcd_to_ehci(hcd);
1099 
1100 	spin_lock_irq(&ehci->lock);
1101 	drop_tt(udev);
1102 	spin_unlock_irq(&ehci->lock);
1103 }
1104 
1105 /*-------------------------------------------------------------------------*/
1106 
1107 #ifdef	CONFIG_PM
1108 
1109 /* Clear wakeup signal locked in zhaoxin platform when device plug in. */
1110 static void ehci_zx_wakeup_clear(struct ehci_hcd *ehci)
1111 {
1112 	u32 __iomem	*reg = &ehci->regs->port_status[4];
1113 	u32 		t1 = ehci_readl(ehci, reg);
1114 
1115 	t1 &= (u32)~0xf0000;
1116 	t1 |= PORT_TEST_FORCE;
1117 	ehci_writel(ehci, t1, reg);
1118 	t1 = ehci_readl(ehci, reg);
1119 	msleep(1);
1120 	t1 &= (u32)~0xf0000;
1121 	ehci_writel(ehci, t1, reg);
1122 	ehci_readl(ehci, reg);
1123 	msleep(1);
1124 	t1 = ehci_readl(ehci, reg);
1125 	ehci_writel(ehci, t1 | PORT_CSC, reg);
1126 	ehci_readl(ehci, reg);
1127 }
1128 
1129 /* suspend/resume, section 4.3 */
1130 
1131 /* These routines handle the generic parts of controller suspend/resume */
1132 
1133 int ehci_suspend(struct usb_hcd *hcd, bool do_wakeup)
1134 {
1135 	struct ehci_hcd		*ehci = hcd_to_ehci(hcd);
1136 
1137 	if (time_before(jiffies, ehci->next_statechange))
1138 		msleep(10);
1139 
1140 	/*
1141 	 * Root hub was already suspended.  Disable IRQ emission and
1142 	 * mark HW unaccessible.  The PM and USB cores make sure that
1143 	 * the root hub is either suspended or stopped.
1144 	 */
1145 	ehci_prepare_ports_for_controller_suspend(ehci, do_wakeup);
1146 
1147 	spin_lock_irq(&ehci->lock);
1148 	ehci_writel(ehci, 0, &ehci->regs->intr_enable);
1149 	(void) ehci_readl(ehci, &ehci->regs->intr_enable);
1150 
1151 	clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1152 	spin_unlock_irq(&ehci->lock);
1153 
1154 	synchronize_irq(hcd->irq);
1155 
1156 	/* Check for race with a wakeup request */
1157 	if (do_wakeup && HCD_WAKEUP_PENDING(hcd)) {
1158 		ehci_resume(hcd, false);
1159 		return -EBUSY;
1160 	}
1161 
1162 	return 0;
1163 }
1164 EXPORT_SYMBOL_GPL(ehci_suspend);
1165 
1166 /* Returns 0 if power was preserved, 1 if power was lost */
1167 int ehci_resume(struct usb_hcd *hcd, bool force_reset)
1168 {
1169 	struct ehci_hcd		*ehci = hcd_to_ehci(hcd);
1170 
1171 	if (time_before(jiffies, ehci->next_statechange))
1172 		msleep(100);
1173 
1174 	/* Mark hardware accessible again as we are back to full power by now */
1175 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1176 
1177 	if (ehci->shutdown)
1178 		return 0;		/* Controller is dead */
1179 
1180 	if (ehci->zx_wakeup_clear_needed)
1181 		ehci_zx_wakeup_clear(ehci);
1182 
1183 	/*
1184 	 * If CF is still set and reset isn't forced
1185 	 * then we maintained suspend power.
1186 	 * Just undo the effect of ehci_suspend().
1187 	 */
1188 	if (ehci_readl(ehci, &ehci->regs->configured_flag) == FLAG_CF &&
1189 			!force_reset) {
1190 		int	mask = INTR_MASK;
1191 
1192 		ehci_prepare_ports_for_controller_resume(ehci);
1193 
1194 		spin_lock_irq(&ehci->lock);
1195 		if (ehci->shutdown)
1196 			goto skip;
1197 
1198 		if (!hcd->self.root_hub->do_remote_wakeup)
1199 			mask &= ~STS_PCD;
1200 		ehci_writel(ehci, mask, &ehci->regs->intr_enable);
1201 		ehci_readl(ehci, &ehci->regs->intr_enable);
1202  skip:
1203 		spin_unlock_irq(&ehci->lock);
1204 		return 0;
1205 	}
1206 
1207 	/*
1208 	 * Else reset, to cope with power loss or resume from hibernation
1209 	 * having let the firmware kick in during reboot.
1210 	 */
1211 	usb_root_hub_lost_power(hcd->self.root_hub);
1212 	(void) ehci_halt(ehci);
1213 	(void) ehci_reset(ehci);
1214 
1215 	spin_lock_irq(&ehci->lock);
1216 	if (ehci->shutdown)
1217 		goto skip;
1218 
1219 	ehci_writel(ehci, ehci->command, &ehci->regs->command);
1220 	ehci_writel(ehci, FLAG_CF, &ehci->regs->configured_flag);
1221 	ehci_readl(ehci, &ehci->regs->command);	/* unblock posted writes */
1222 
1223 	ehci->rh_state = EHCI_RH_SUSPENDED;
1224 	spin_unlock_irq(&ehci->lock);
1225 
1226 	return 1;
1227 }
1228 EXPORT_SYMBOL_GPL(ehci_resume);
1229 
1230 #endif
1231 
1232 /*-------------------------------------------------------------------------*/
1233 
1234 /*
1235  * Generic structure: This gets copied for platform drivers so that
1236  * individual entries can be overridden as needed.
1237  */
1238 
1239 static const struct hc_driver ehci_hc_driver = {
1240 	.description =		hcd_name,
1241 	.product_desc =		"EHCI Host Controller",
1242 	.hcd_priv_size =	sizeof(struct ehci_hcd),
1243 
1244 	/*
1245 	 * generic hardware linkage
1246 	 */
1247 	.irq =			ehci_irq,
1248 	.flags =		HCD_MEMORY | HCD_DMA | HCD_USB2 | HCD_BH,
1249 
1250 	/*
1251 	 * basic lifecycle operations
1252 	 */
1253 	.reset =		ehci_setup,
1254 	.start =		ehci_run,
1255 	.stop =			ehci_stop,
1256 	.shutdown =		ehci_shutdown,
1257 
1258 	/*
1259 	 * managing i/o requests and associated device resources
1260 	 */
1261 	.urb_enqueue =		ehci_urb_enqueue,
1262 	.urb_dequeue =		ehci_urb_dequeue,
1263 	.endpoint_disable =	ehci_endpoint_disable,
1264 	.endpoint_reset =	ehci_endpoint_reset,
1265 	.clear_tt_buffer_complete =	ehci_clear_tt_buffer_complete,
1266 
1267 	/*
1268 	 * scheduling support
1269 	 */
1270 	.get_frame_number =	ehci_get_frame,
1271 
1272 	/*
1273 	 * root hub support
1274 	 */
1275 	.hub_status_data =	ehci_hub_status_data,
1276 	.hub_control =		ehci_hub_control,
1277 	.bus_suspend =		ehci_bus_suspend,
1278 	.bus_resume =		ehci_bus_resume,
1279 	.relinquish_port =	ehci_relinquish_port,
1280 	.port_handed_over =	ehci_port_handed_over,
1281 	.get_resuming_ports =	ehci_get_resuming_ports,
1282 
1283 	/*
1284 	 * device support
1285 	 */
1286 	.free_dev =		ehci_remove_device,
1287 #ifdef CONFIG_USB_HCD_TEST_MODE
1288 	/* EH SINGLE_STEP_SET_FEATURE test support */
1289 	.submit_single_step_set_feature	= ehci_submit_single_step_set_feature,
1290 #endif
1291 };
1292 
1293 void ehci_init_driver(struct hc_driver *drv,
1294 		const struct ehci_driver_overrides *over)
1295 {
1296 	/* Copy the generic table to drv and then apply the overrides */
1297 	*drv = ehci_hc_driver;
1298 
1299 	if (over) {
1300 		drv->hcd_priv_size += over->extra_priv_size;
1301 		if (over->reset)
1302 			drv->reset = over->reset;
1303 		if (over->port_power)
1304 			drv->port_power = over->port_power;
1305 	}
1306 }
1307 EXPORT_SYMBOL_GPL(ehci_init_driver);
1308 
1309 /*-------------------------------------------------------------------------*/
1310 
1311 MODULE_DESCRIPTION(DRIVER_DESC);
1312 MODULE_AUTHOR (DRIVER_AUTHOR);
1313 MODULE_LICENSE ("GPL");
1314 
1315 #ifdef CONFIG_USB_EHCI_SH
1316 #include "ehci-sh.c"
1317 #endif
1318 
1319 #ifdef CONFIG_PPC_PS3
1320 #include "ehci-ps3.c"
1321 #endif
1322 
1323 #ifdef CONFIG_USB_EHCI_HCD_PPC_OF
1324 #include "ehci-ppc-of.c"
1325 #endif
1326 
1327 #ifdef CONFIG_XPS_USB_HCD_XILINX
1328 #include "ehci-xilinx-of.c"
1329 #endif
1330 
1331 #ifdef CONFIG_SPARC_LEON
1332 #include "ehci-grlib.c"
1333 #endif
1334 
1335 static struct platform_driver * const platform_drivers[] = {
1336 #ifdef CONFIG_USB_EHCI_SH
1337 	&ehci_hcd_sh_driver,
1338 #endif
1339 #ifdef CONFIG_USB_EHCI_HCD_PPC_OF
1340 	&ehci_hcd_ppc_of_driver,
1341 #endif
1342 #ifdef CONFIG_XPS_USB_HCD_XILINX
1343 	&ehci_hcd_xilinx_of_driver,
1344 #endif
1345 #ifdef CONFIG_SPARC_LEON
1346 	&ehci_grlib_driver,
1347 #endif
1348 };
1349 
1350 static int __init ehci_hcd_init(void)
1351 {
1352 	int retval = 0;
1353 
1354 	if (usb_disabled())
1355 		return -ENODEV;
1356 
1357 	set_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
1358 	if (test_bit(USB_UHCI_LOADED, &usb_hcds_loaded) ||
1359 			test_bit(USB_OHCI_LOADED, &usb_hcds_loaded))
1360 		printk(KERN_WARNING "Warning! ehci_hcd should always be loaded"
1361 				" before uhci_hcd and ohci_hcd, not after\n");
1362 
1363 	pr_debug("%s: block sizes: qh %zd qtd %zd itd %zd sitd %zd\n",
1364 		 hcd_name,
1365 		 sizeof(struct ehci_qh), sizeof(struct ehci_qtd),
1366 		 sizeof(struct ehci_itd), sizeof(struct ehci_sitd));
1367 
1368 #ifdef CONFIG_DYNAMIC_DEBUG
1369 	ehci_debug_root = debugfs_create_dir("ehci", usb_debug_root);
1370 #endif
1371 
1372 	retval = platform_register_drivers(platform_drivers, ARRAY_SIZE(platform_drivers));
1373 	if (retval < 0)
1374 		goto clean0;
1375 
1376 #ifdef CONFIG_PPC_PS3
1377 	retval = ps3_ehci_driver_register(&ps3_ehci_driver);
1378 	if (retval < 0)
1379 		goto clean1;
1380 #endif
1381 
1382 	return 0;
1383 
1384 #ifdef CONFIG_PPC_PS3
1385 clean1:
1386 #endif
1387 	platform_unregister_drivers(platform_drivers, ARRAY_SIZE(platform_drivers));
1388 clean0:
1389 #ifdef CONFIG_DYNAMIC_DEBUG
1390 	debugfs_remove(ehci_debug_root);
1391 	ehci_debug_root = NULL;
1392 #endif
1393 	clear_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
1394 	return retval;
1395 }
1396 module_init(ehci_hcd_init);
1397 
1398 static void __exit ehci_hcd_cleanup(void)
1399 {
1400 #ifdef CONFIG_PPC_PS3
1401 	ps3_ehci_driver_unregister(&ps3_ehci_driver);
1402 #endif
1403 	platform_unregister_drivers(platform_drivers, ARRAY_SIZE(platform_drivers));
1404 #ifdef CONFIG_DYNAMIC_DEBUG
1405 	debugfs_remove(ehci_debug_root);
1406 #endif
1407 	clear_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
1408 }
1409 module_exit(ehci_hcd_cleanup);
1410