ohci-hub.c 21.3 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825
/*
 * OHCI HCD (Host Controller Driver) for USB.
 *
 * (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
 * (C) Copyright 2000-2004 David Brownell <dbrownell@users.sourceforge.net>
 *
 * This file is licenced under GPL
 */

/*-------------------------------------------------------------------------*/

/*
 * OHCI Root Hub ... the nonsharable stuff
 */

#define dbg_port(hc,label,num,value) \
	ohci_dbg (hc, \
		"%s roothub.portstatus [%d] " \
		"= 0x%08x%s%s%s%s%s%s%s%s%s%s%s%s\n", \
		label, num, temp, \
		(temp & RH_PS_PRSC) ? " PRSC" : "", \
		(temp & RH_PS_OCIC) ? " OCIC" : "", \
		(temp & RH_PS_PSSC) ? " PSSC" : "", \
		(temp & RH_PS_PESC) ? " PESC" : "", \
		(temp & RH_PS_CSC) ? " CSC" : "", \
		\
		(temp & RH_PS_LSDA) ? " LSDA" : "", \
		(temp & RH_PS_PPS) ? " PPS" : "", \
		(temp & RH_PS_PRS) ? " PRS" : "", \
		(temp & RH_PS_POCI) ? " POCI" : "", \
		(temp & RH_PS_PSS) ? " PSS" : "", \
		\
		(temp & RH_PS_PES) ? " PES" : "", \
		(temp & RH_PS_CCS) ? " CCS" : "" \
		);

/*-------------------------------------------------------------------------*/

#define OHCI_SCHED_ENABLES \
	(OHCI_CTRL_CLE|OHCI_CTRL_BLE|OHCI_CTRL_PLE|OHCI_CTRL_IE)

static void dl_done_list (struct ohci_hcd *);
static void finish_unlinks (struct ohci_hcd *, u16);

#ifdef	CONFIG_PM
static int ohci_rh_suspend (struct ohci_hcd *ohci, int autostop)
__releases(ohci->lock)
__acquires(ohci->lock)
{
	int			status = 0;

	ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
	switch (ohci->hc_control & OHCI_CTRL_HCFS) {
	case OHCI_USB_RESUME:
		ohci_dbg (ohci, "resume/suspend?\n");
		ohci->hc_control &= ~OHCI_CTRL_HCFS;
		ohci->hc_control |= OHCI_USB_RESET;
		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
		(void) ohci_readl (ohci, &ohci->regs->control);
		/* FALL THROUGH */
	case OHCI_USB_RESET:
		status = -EBUSY;
		ohci_dbg (ohci, "needs reinit!\n");
		goto done;
	case OHCI_USB_SUSPEND:
		if (!ohci->autostop) {
			ohci_dbg (ohci, "already suspended\n");
			goto done;
		}
	}
	ohci_dbg (ohci, "%s root hub\n",
			autostop ? "auto-stop" : "suspend");

	/* First stop any processing */
	if (!autostop && (ohci->hc_control & OHCI_SCHED_ENABLES)) {
		ohci->hc_control &= ~OHCI_SCHED_ENABLES;
		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
		ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
		ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrstatus);

		/* sched disables take effect on the next frame,
		 * then the last WDH could take 6+ msec
		 */
		ohci_dbg (ohci, "stopping schedules ...\n");
		ohci->autostop = 0;
		spin_unlock_irq (&ohci->lock);
		msleep (8);
		spin_lock_irq (&ohci->lock);
	}
	dl_done_list (ohci);
	finish_unlinks (ohci, ohci_frame_no(ohci));

	/* maybe resume can wake root hub */
	if (ohci_to_hcd(ohci)->self.root_hub->do_remote_wakeup || autostop) {
		ohci->hc_control |= OHCI_CTRL_RWE;
	} else {
		ohci_writel(ohci, OHCI_INTR_RHSC | OHCI_INTR_RD,
				&ohci->regs->intrdisable);
		ohci->hc_control &= ~OHCI_CTRL_RWE;
	}

	/* Suspend hub ... this is the "global (to this bus) suspend" mode,
	 * which doesn't imply ports will first be individually suspended.
	 */
	ohci->hc_control &= ~OHCI_CTRL_HCFS;
	ohci->hc_control |= OHCI_USB_SUSPEND;
	ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
	(void) ohci_readl (ohci, &ohci->regs->control);

	/* no resumes until devices finish suspending */
	if (!autostop) {
		ohci->next_statechange = jiffies + msecs_to_jiffies (5);
		ohci->autostop = 0;
		ohci->rh_state = OHCI_RH_SUSPENDED;
	}

done:
	return status;
}

static inline struct ed *find_head (struct ed *ed)
{
	/* for bulk and control lists */
	while (ed->ed_prev)
		ed = ed->ed_prev;
	return ed;
}

/* caller has locked the root hub */
static int ohci_rh_resume (struct ohci_hcd *ohci)
__releases(ohci->lock)
__acquires(ohci->lock)
{
	struct usb_hcd		*hcd = ohci_to_hcd (ohci);
	u32			temp, enables;
	int			status = -EINPROGRESS;
	int			autostopped = ohci->autostop;

	ohci->autostop = 0;
	ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);

	if (ohci->hc_control & (OHCI_CTRL_IR | OHCI_SCHED_ENABLES)) {
		/* this can happen after resuming a swsusp snapshot */
		if (ohci->rh_state != OHCI_RH_RUNNING) {
			ohci_dbg (ohci, "BIOS/SMM active, control %03x\n",
					ohci->hc_control);
			status = -EBUSY;
		/* this happens when pmcore resumes HC then root */
		} else {
			ohci_dbg (ohci, "duplicate resume\n");
			status = 0;
		}
	} else switch (ohci->hc_control & OHCI_CTRL_HCFS) {
	case OHCI_USB_SUSPEND:
		ohci->hc_control &= ~(OHCI_CTRL_HCFS|OHCI_SCHED_ENABLES);
		ohci->hc_control |= OHCI_USB_RESUME;
		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
		(void) ohci_readl (ohci, &ohci->regs->control);
		ohci_dbg (ohci, "%s root hub\n",
				autostopped ? "auto-start" : "resume");
		break;
	case OHCI_USB_RESUME:
		/* HCFS changes sometime after INTR_RD */
		ohci_dbg(ohci, "%swakeup root hub\n",
				autostopped ? "auto-" : "");
		break;
	case OHCI_USB_OPER:
		/* this can happen after resuming a swsusp snapshot */
		ohci_dbg (ohci, "snapshot resume? reinit\n");
		status = -EBUSY;
		break;
	default:		/* RESET, we lost power */
		ohci_dbg (ohci, "lost power\n");
		status = -EBUSY;
	}
	if (status == -EBUSY) {
		if (!autostopped) {
			spin_unlock_irq (&ohci->lock);
			(void) ohci_init (ohci);
			status = ohci_restart (ohci);

			usb_root_hub_lost_power(hcd->self.root_hub);

			spin_lock_irq (&ohci->lock);
		}
		return status;
	}
	if (status != -EINPROGRESS)
		return status;
	if (autostopped)
		goto skip_resume;
	spin_unlock_irq (&ohci->lock);

	/* Some controllers (lucent erratum) need extra-long delays */
	msleep (20 /* usb 11.5.1.10 */ + 12 /* 32 msec counter */ + 1);

	temp = ohci_readl (ohci, &ohci->regs->control);
	temp &= OHCI_CTRL_HCFS;
	if (temp != OHCI_USB_RESUME) {
		ohci_err (ohci, "controller won't resume\n");
		spin_lock_irq(&ohci->lock);
		return -EBUSY;
	}

	/* disable old schedule state, reinit from scratch */
	ohci_writel (ohci, 0, &ohci->regs->ed_controlhead);
	ohci_writel (ohci, 0, &ohci->regs->ed_controlcurrent);
	ohci_writel (ohci, 0, &ohci->regs->ed_bulkhead);
	ohci_writel (ohci, 0, &ohci->regs->ed_bulkcurrent);
	ohci_writel (ohci, 0, &ohci->regs->ed_periodcurrent);
	ohci_writel (ohci, (u32) ohci->hcca_dma, &ohci->regs->hcca);

	/* Sometimes PCI D3 suspend trashes frame timings ... */
	periodic_reinit (ohci);

	/* the following code is executed with ohci->lock held and
	 * irqs disabled if and only if autostopped is true
	 */

skip_resume:
	/* interrupts might have been disabled */
	ohci_writel (ohci, OHCI_INTR_INIT, &ohci->regs->intrenable);
	if (ohci->ed_rm_list)
		ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrenable);

	/* Then re-enable operations */
	ohci_writel (ohci, OHCI_USB_OPER, &ohci->regs->control);
	(void) ohci_readl (ohci, &ohci->regs->control);
	if (!autostopped)
		msleep (3);

	temp = ohci->hc_control;
	temp &= OHCI_CTRL_RWC;
	temp |= OHCI_CONTROL_INIT | OHCI_USB_OPER;
	ohci->hc_control = temp;
	ohci_writel (ohci, temp, &ohci->regs->control);
	(void) ohci_readl (ohci, &ohci->regs->control);

	/* TRSMRCY */
	if (!autostopped) {
		msleep (10);
		spin_lock_irq (&ohci->lock);
	}
	/* now ohci->lock is always held and irqs are always disabled */

	/* keep it alive for more than ~5x suspend + resume costs */
	ohci->next_statechange = jiffies + STATECHANGE_DELAY;

	/* maybe turn schedules back on */
	enables = 0;
	temp = 0;
	if (!ohci->ed_rm_list) {
		if (ohci->ed_controltail) {
			ohci_writel (ohci,
					find_head (ohci->ed_controltail)->dma,
					&ohci->regs->ed_controlhead);
			enables |= OHCI_CTRL_CLE;
			temp |= OHCI_CLF;
		}
		if (ohci->ed_bulktail) {
			ohci_writel (ohci, find_head (ohci->ed_bulktail)->dma,
				&ohci->regs->ed_bulkhead);
			enables |= OHCI_CTRL_BLE;
			temp |= OHCI_BLF;
		}
	}
	if (hcd->self.bandwidth_isoc_reqs || hcd->self.bandwidth_int_reqs)
		enables |= OHCI_CTRL_PLE|OHCI_CTRL_IE;
	if (enables) {
		ohci_dbg (ohci, "restarting schedules ... %08x\n", enables);
		ohci->hc_control |= enables;
		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
		if (temp)
			ohci_writel (ohci, temp, &ohci->regs->cmdstatus);
		(void) ohci_readl (ohci, &ohci->regs->control);
	}

	ohci->rh_state = OHCI_RH_RUNNING;
	return 0;
}

static int ohci_bus_suspend (struct usb_hcd *hcd)
{
	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
	int			rc;

	spin_lock_irq (&ohci->lock);

	if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
		rc = -ESHUTDOWN;
	else
		rc = ohci_rh_suspend (ohci, 0);
	spin_unlock_irq (&ohci->lock);
	return rc;
}

static int ohci_bus_resume (struct usb_hcd *hcd)
{
	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
	int			rc;

	if (time_before (jiffies, ohci->next_statechange))
		msleep(5);

	spin_lock_irq (&ohci->lock);

	if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
		rc = -ESHUTDOWN;
	else
		rc = ohci_rh_resume (ohci);
	spin_unlock_irq (&ohci->lock);

	/* poll until we know a device is connected or we autostop */
	if (rc == 0)
		usb_hcd_poll_rh_status(hcd);
	return rc;
}

/* Carry out the final steps of resuming the controller device */
static void ohci_finish_controller_resume(struct usb_hcd *hcd)
{
	struct ohci_hcd		*ohci = hcd_to_ohci(hcd);
	int			port;
	bool			need_reinit = false;

	/* See if the controller is already running or has been reset */
	ohci->hc_control = ohci_readl(ohci, &ohci->regs->control);
	if (ohci->hc_control & (OHCI_CTRL_IR | OHCI_SCHED_ENABLES)) {
		need_reinit = true;
	} else {
		switch (ohci->hc_control & OHCI_CTRL_HCFS) {
		case OHCI_USB_OPER:
		case OHCI_USB_RESET:
			need_reinit = true;
		}
	}

	/* If needed, reinitialize and suspend the root hub */
	if (need_reinit) {
		spin_lock_irq(&ohci->lock);
		ohci_rh_resume(ohci);
		ohci_rh_suspend(ohci, 0);
		spin_unlock_irq(&ohci->lock);
	}

	/* Normally just turn on port power and enable interrupts */
	else {
		ohci_dbg(ohci, "powerup ports\n");
		for (port = 0; port < ohci->num_ports; port++)
			ohci_writel(ohci, RH_PS_PPS,
					&ohci->regs->roothub.portstatus[port]);

		ohci_writel(ohci, OHCI_INTR_MIE, &ohci->regs->intrenable);
		ohci_readl(ohci, &ohci->regs->intrenable);
		msleep(20);
	}

	usb_hcd_resume_root_hub(hcd);
}

/* Carry out polling-, autostop-, and autoresume-related state changes */
static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
		int any_connected, int rhsc_status)
{
	int	poll_rh = 1;
	int	rhsc_enable;

	/* Some broken controllers never turn off RHSC in the interrupt
	 * status register.  For their sake we won't re-enable RHSC
	 * interrupts if the interrupt bit is already active.
	 */
	rhsc_enable = ohci_readl(ohci, &ohci->regs->intrenable) &
			OHCI_INTR_RHSC;

	switch (ohci->hc_control & OHCI_CTRL_HCFS) {
	case OHCI_USB_OPER:
		/* If no status changes are pending, enable RHSC interrupts. */
		if (!rhsc_enable && !rhsc_status && !changed) {
			rhsc_enable = OHCI_INTR_RHSC;
			ohci_writel(ohci, rhsc_enable, &ohci->regs->intrenable);
		}

		/* Keep on polling until we know a device is connected
		 * and RHSC is enabled, or until we autostop.
		 */
		if (!ohci->autostop) {
			if (any_connected ||
					!device_may_wakeup(&ohci_to_hcd(ohci)
						->self.root_hub->dev)) {
				if (rhsc_enable)
					poll_rh = 0;
			} else {
				ohci->autostop = 1;
				ohci->next_statechange = jiffies + HZ;
			}

		/* if no devices have been attached for one second, autostop */
		} else {
			if (changed || any_connected) {
				ohci->autostop = 0;
				ohci->next_statechange = jiffies +
						STATECHANGE_DELAY;
			} else if (time_after_eq(jiffies,
						ohci->next_statechange)
					&& !ohci->ed_rm_list
					&& !(ohci->hc_control &
						OHCI_SCHED_ENABLES)) {
				ohci_rh_suspend(ohci, 1);
				if (rhsc_enable)
					poll_rh = 0;
			}
		}
		break;

	case OHCI_USB_SUSPEND:
	case OHCI_USB_RESUME:
		/* if there is a port change, autostart or ask to be resumed */
		if (changed) {
			if (ohci->autostop)
				ohci_rh_resume(ohci);
			else
				usb_hcd_resume_root_hub(ohci_to_hcd(ohci));

		/* If remote wakeup is disabled, stop polling */
		} else if (!ohci->autostop &&
				!ohci_to_hcd(ohci)->self.root_hub->
					do_remote_wakeup) {
			poll_rh = 0;

		} else {
			/* If no status changes are pending,
			 * enable RHSC interrupts
			 */
			if (!rhsc_enable && !rhsc_status) {
				rhsc_enable = OHCI_INTR_RHSC;
				ohci_writel(ohci, rhsc_enable,
						&ohci->regs->intrenable);
			}
			/* Keep polling until RHSC is enabled */
			if (rhsc_enable)
				poll_rh = 0;
		}
		break;
	}
	return poll_rh;
}

#else	/* CONFIG_PM */

static inline int ohci_rh_resume(struct ohci_hcd *ohci)
{
	return 0;
}

/* Carry out polling-related state changes.
 * autostop isn't used when CONFIG_PM is turned off.
 */
static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
		int any_connected, int rhsc_status)
{
	/* If RHSC is enabled, don't poll */
	if (ohci_readl(ohci, &ohci->regs->intrenable) & OHCI_INTR_RHSC)
		return 0;

	/* If status changes are pending, continue polling.
	 * Conversely, if no status changes are pending but the RHSC
	 * status bit was set, then RHSC may be broken so continue polling.
	 */
	if (changed || rhsc_status)
		return 1;

	/* It's safe to re-enable RHSC interrupts */
	ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrenable);
	return 0;
}

#endif	/* CONFIG_PM */

/*-------------------------------------------------------------------------*/

/* build "status change" packet (one or two bytes) from HC registers */

static int
ohci_hub_status_data (struct usb_hcd *hcd, char *buf)
{
	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
	int		i, changed = 0, length = 1;
	int		any_connected = 0;
	int		rhsc_status;
	unsigned long	flags;

	spin_lock_irqsave (&ohci->lock, flags);
	if (!HCD_HW_ACCESSIBLE(hcd))
		goto done;

	/* undocumented erratum seen on at least rev D */
	if ((ohci->flags & OHCI_QUIRK_AMD756)
			&& (roothub_a (ohci) & RH_A_NDP) > MAX_ROOT_PORTS) {
		ohci_warn (ohci, "bogus NDP, rereads as NDP=%d\n",
			  ohci_readl (ohci, &ohci->regs->roothub.a) & RH_A_NDP);
		/* retry later; "should not happen" */
		goto done;
	}

	/* init status */
	if (roothub_status (ohci) & (RH_HS_LPSC | RH_HS_OCIC))
		buf [0] = changed = 1;
	else
		buf [0] = 0;
	if (ohci->num_ports > 7) {
		buf [1] = 0;
		length++;
	}

	/* Clear the RHSC status flag before reading the port statuses */
	ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrstatus);
	rhsc_status = ohci_readl(ohci, &ohci->regs->intrstatus) &
			OHCI_INTR_RHSC;

	/* look at each port */
	for (i = 0; i < ohci->num_ports; i++) {
		u32	status = roothub_portstatus (ohci, i);

		/* can't autostop if ports are connected */
		any_connected |= (status & RH_PS_CCS);

		if (status & (RH_PS_CSC | RH_PS_PESC | RH_PS_PSSC
				| RH_PS_OCIC | RH_PS_PRSC)) {
			changed = 1;
			if (i < 7)
			    buf [0] |= 1 << (i + 1);
			else
			    buf [1] |= 1 << (i - 7);
		}
	}

	if (ohci_root_hub_state_changes(ohci, changed,
			any_connected, rhsc_status))
		set_bit(HCD_FLAG_POLL_RH, &hcd->flags);
	else
		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);


done:
	spin_unlock_irqrestore (&ohci->lock, flags);

	return changed ? length : 0;
}

/*-------------------------------------------------------------------------*/

static void
ohci_hub_descriptor (
	struct ohci_hcd			*ohci,
	struct usb_hub_descriptor	*desc
) {
	u32		rh = roothub_a (ohci);
	u16		temp;

	desc->bDescriptorType = 0x29;
	desc->bPwrOn2PwrGood = (rh & RH_A_POTPGT) >> 24;
	desc->bHubContrCurrent = 0;

	desc->bNbrPorts = ohci->num_ports;
	temp = 1 + (ohci->num_ports / 8);
	desc->bDescLength = 7 + 2 * temp;

	temp = 0;
	if (rh & RH_A_NPS)		/* no power switching? */
	    temp |= 0x0002;
	if (rh & RH_A_PSM)		/* per-port power switching? */
	    temp |= 0x0001;
	if (rh & RH_A_NOCP)		/* no overcurrent reporting? */
	    temp |= 0x0010;
	else if (rh & RH_A_OCPM)	/* per-port overcurrent reporting? */
	    temp |= 0x0008;
	desc->wHubCharacteristics = (__force __u16)cpu_to_hc16(ohci, temp);

	/* ports removable, and usb 1.0 legacy PortPwrCtrlMask */
	rh = roothub_b (ohci);
	memset(desc->u.hs.DeviceRemovable, 0xff,
			sizeof(desc->u.hs.DeviceRemovable));
	desc->u.hs.DeviceRemovable[0] = rh & RH_B_DR;
	if (ohci->num_ports > 7) {
		desc->u.hs.DeviceRemovable[1] = (rh & RH_B_DR) >> 8;
		desc->u.hs.DeviceRemovable[2] = 0xff;
	} else
		desc->u.hs.DeviceRemovable[1] = 0xff;
}

/*-------------------------------------------------------------------------*/

#ifdef	CONFIG_USB_OTG

static int ohci_start_port_reset (struct usb_hcd *hcd, unsigned port)
{
	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
	u32			status;

	if (!port)
		return -EINVAL;
	port--;

	/* start port reset before HNP protocol times out */
	status = ohci_readl(ohci, &ohci->regs->roothub.portstatus [port]);
	if (!(status & RH_PS_CCS))
		return -ENODEV;

	/* khubd will finish the reset later */
	ohci_writel(ohci, RH_PS_PRS, &ohci->regs->roothub.portstatus [port]);
	return 0;
}

#else

#define	ohci_start_port_reset		NULL

#endif

/*-------------------------------------------------------------------------*/


/* See usb 7.1.7.5:  root hubs must issue at least 50 msec reset signaling,
 * not necessarily continuous ... to guard against resume signaling.
 * The short timeout is safe for non-root hubs, and is backward-compatible
 * with earlier Linux hosts.
 */
#ifdef	CONFIG_USB_SUSPEND
#define	PORT_RESET_MSEC		50
#else
#define	PORT_RESET_MSEC		10
#endif

/* this timer value might be vendor-specific ... */
#define	PORT_RESET_HW_MSEC	10

/* wrap-aware logic morphed from <linux/jiffies.h> */
#define tick_before(t1,t2) ((s16)(((s16)(t1))-((s16)(t2))) < 0)

/* called from some task, normally khubd */
static inline int root_port_reset (struct ohci_hcd *ohci, unsigned port)
{
	__hc32 __iomem *portstat = &ohci->regs->roothub.portstatus [port];
	u32	temp = 0;
	u16	now = ohci_readl(ohci, &ohci->regs->fmnumber);
	u16	reset_done = now + PORT_RESET_MSEC;
	int	limit_1 = DIV_ROUND_UP(PORT_RESET_MSEC, PORT_RESET_HW_MSEC);

	/* build a "continuous enough" reset signal, with up to
	 * 3msec gap between pulses.  scheduler HZ==100 must work;
	 * this might need to be deadline-scheduled.
	 */
	do {
		int limit_2;

		/* spin until any current reset finishes */
		limit_2 = PORT_RESET_HW_MSEC * 2;
		while (--limit_2 >= 0) {
			temp = ohci_readl (ohci, portstat);
			/* handle e.g. CardBus eject */
			if (temp == ~(u32)0)
				return -ESHUTDOWN;
			if (!(temp & RH_PS_PRS))
				break;
			udelay (500);
		}

		/* timeout (a hardware error) has been observed when
		 * EHCI sets CF while this driver is resetting a port;
		 * presumably other disconnect paths might do it too.
		 */
		if (limit_2 < 0) {
			ohci_dbg(ohci,
				"port[%d] reset timeout, stat %08x\n",
				port, temp);
			break;
		}

		if (!(temp & RH_PS_CCS))
			break;
		if (temp & RH_PS_PRSC)
			ohci_writel (ohci, RH_PS_PRSC, portstat);

		/* start the next reset, sleep till it's probably done */
		ohci_writel (ohci, RH_PS_PRS, portstat);
		msleep(PORT_RESET_HW_MSEC);
		now = ohci_readl(ohci, &ohci->regs->fmnumber);
	} while (tick_before(now, reset_done) && --limit_1 >= 0);

	/* caller synchronizes using PRSC ... and handles PRS
	 * still being set when this returns.
	 */

	return 0;
}

static int ohci_hub_control (
	struct usb_hcd	*hcd,
	u16		typeReq,
	u16		wValue,
	u16		wIndex,
	char		*buf,
	u16		wLength
) {
	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
	int		ports = ohci->num_ports;
	u32		temp;
	int		retval = 0;

	if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
		return -ESHUTDOWN;

	switch (typeReq) {
	case ClearHubFeature:
		switch (wValue) {
		case C_HUB_OVER_CURRENT:
			ohci_writel (ohci, RH_HS_OCIC,
					&ohci->regs->roothub.status);
		case C_HUB_LOCAL_POWER:
			break;
		default:
			goto error;
		}
		break;
	case ClearPortFeature:
		if (!wIndex || wIndex > ports)
			goto error;
		wIndex--;

		switch (wValue) {
		case USB_PORT_FEAT_ENABLE:
			temp = RH_PS_CCS;
			break;
		case USB_PORT_FEAT_C_ENABLE:
			temp = RH_PS_PESC;
			break;
		case USB_PORT_FEAT_SUSPEND:
			temp = RH_PS_POCI;
			break;
		case USB_PORT_FEAT_C_SUSPEND:
			temp = RH_PS_PSSC;
			break;
		case USB_PORT_FEAT_POWER:
			temp = RH_PS_LSDA;
			break;
		case USB_PORT_FEAT_C_CONNECTION:
			temp = RH_PS_CSC;
			break;
		case USB_PORT_FEAT_C_OVER_CURRENT:
			temp = RH_PS_OCIC;
			break;
		case USB_PORT_FEAT_C_RESET:
			temp = RH_PS_PRSC;
			break;
		default:
			goto error;
		}
		ohci_writel (ohci, temp,
				&ohci->regs->roothub.portstatus [wIndex]);
		// ohci_readl (ohci, &ohci->regs->roothub.portstatus [wIndex]);
		break;
	case GetHubDescriptor:
		ohci_hub_descriptor (ohci, (struct usb_hub_descriptor *) buf);
		break;
	case GetHubStatus:
		temp = roothub_status (ohci) & ~(RH_HS_CRWE | RH_HS_DRWE);
		put_unaligned_le32(temp, buf);
		break;
	case GetPortStatus:
		if (!wIndex || wIndex > ports)
			goto error;
		wIndex--;
		temp = roothub_portstatus (ohci, wIndex);
		put_unaligned_le32(temp, buf);

#ifndef	OHCI_VERBOSE_DEBUG
	if (*(u16*)(buf+2))	/* only if wPortChange is interesting */
#endif
		dbg_port (ohci, "GetStatus", wIndex, temp);
		break;
	case SetHubFeature:
		switch (wValue) {
		case C_HUB_OVER_CURRENT:
			// FIXME:  this can be cleared, yes?
		case C_HUB_LOCAL_POWER:
			break;
		default:
			goto error;
		}
		break;
	case SetPortFeature:
		if (!wIndex || wIndex > ports)
			goto error;
		wIndex--;
		switch (wValue) {
		case USB_PORT_FEAT_SUSPEND:
#ifdef	CONFIG_USB_OTG
			if (hcd->self.otg_port == (wIndex + 1)
					&& hcd->self.b_hnp_enable)
				ohci->start_hnp(ohci);
			else
#endif
			ohci_writel (ohci, RH_PS_PSS,
				&ohci->regs->roothub.portstatus [wIndex]);
			break;
		case USB_PORT_FEAT_POWER:
			ohci_writel (ohci, RH_PS_PPS,
				&ohci->regs->roothub.portstatus [wIndex]);
			break;
		case USB_PORT_FEAT_RESET:
			retval = root_port_reset (ohci, wIndex);
			break;
		default:
			goto error;
		}
		break;

	default:
error:
		/* "protocol stall" on error */
		retval = -EPIPE;
	}
	return retval;
}