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ohci-hub.c

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    ohci-hub.c 20.19 KiB
    /*
     * 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" : "" \
    		);
    
    /*-------------------------------------------------------------------------*/
    
    /* hcd->hub_irq_enable() */
    static void ohci_rhsc_enable (struct usb_hcd *hcd)
    {
    	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
    
    	spin_lock_irq(&ohci->lock);
    	if (!ohci->autostop)
    		del_timer(&hcd->rh_timer);	/* Prevent next poll */
    	ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrenable);
    	spin_unlock_irq(&ohci->lock);
    }
    
    #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;
    	}
    
    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 (hcd->state == HC_STATE_RESUMING) {
    			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);
    	}
    
    	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(!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)))
    		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(!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)))
    		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);
    		hcd->state = HC_STATE_RESUMING;
    		ohci_rh_resume(ohci);
    		hcd->state = HC_STATE_QUIESCING;
    		ohci_rh_suspend(ohci, 0);
    		hcd->state = HC_STATE_SUSPENDED;
    		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);
    	}
    }
    
    /* 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	poll_rh = 1;
    
    	switch (ohci->hc_control & OHCI_CTRL_HCFS) {
    
    	case OHCI_USB_OPER:
    		/* keep on polling until we know a device is connected
    		 * and RHSC is enabled */
    		if (!ohci->autostop) {
    			if (any_connected ||
    					!device_may_wakeup(&ohci_to_hcd(ohci)
    						->self.root_hub->dev)) {
    				if (ohci_readl(ohci, &ohci->regs->intrenable) &
    						OHCI_INTR_RHSC)
    					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);
    			}
    		}
    		break;
    
    	/* if there is a port change, autostart or ask to be resumed */
    	case OHCI_USB_SUSPEND:
    	case OHCI_USB_RESUME:
    		if (changed) {
    			if (ohci->autostop)
    				ohci_rh_resume(ohci);
    			else
    				usb_hcd_resume_root_hub(ohci_to_hcd(ohci));
    		} else {
    			/* everything is idle, no need for polling */
    			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	poll_rh = 1;
    
    	/* keep on polling until RHSC is enabled */
    	if (ohci_readl(ohci, &ohci->regs->intrenable) & OHCI_INTR_RHSC)
    		poll_rh = 0;
    	return poll_rh;
    }
    
    #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;
    	unsigned long	flags;
    
    	spin_lock_irqsave (&ohci->lock, flags);
    	if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags))
    		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++;
    	}
    
    	/* 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);
    		}
    	}
    
    	hcd->poll_rh = ohci_root_hub_state_changes(ohci, changed,
    			any_connected);
    
    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);
    
    	/* two bitmaps:  ports removable, and usb 1.0 legacy PortPwrCtrlMask */
    	rh = roothub_b (ohci);
    	memset(desc->bitmap, 0xff, sizeof(desc->bitmap));
    	desc->bitmap [0] = rh & RH_B_DR;
    	if (ohci->num_ports > 7) {
    		desc->bitmap [1] = (rh & RH_B_DR) >> 8;
    		desc->bitmap [2] = 0xff;
    	} else
    		desc->bitmap [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;
    }
    
    static void start_hnp(struct ohci_hcd *ohci);
    
    #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 = hcd_to_bus (hcd)->root_hub->maxchild;
    	u32		temp;
    	int		retval = 0;
    
    	if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)))
    		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)
    				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;
    }