ehci-hcd.c

来自「优龙2410linux2.6.8内核源代码」· C语言 代码 · 共 1,101 行 · 第 1/2 页

	 *
	 * Before this point the HC was idle/ready.  After, khubd
	 * and device drivers may start it running.
	 */
	udev->speed = USB_SPEED_HIGH;
	if (hcd_register_root (udev, hcd) != 0) {
		if (hcd->state == USB_STATE_RUNNING)
			ehci_ready (ehci);
		ehci_reset (ehci);
		usb_put_dev (udev); 
		retval = -ENODEV;
		goto done2;
	}

	writel (INTR_MASK, &ehci->regs->intr_enable); /* Turn On Interrupts */

	create_debug_files (ehci);

	return 0;
}

/* always called by thread; normally rmmod */

static void ehci_stop (struct usb_hcd *hcd)
{
	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
	u8			rh_ports, port;

	ehci_dbg (ehci, "stop\n");

	/* no more interrupts ... */
	if (hcd->state == USB_STATE_RUNNING)
		ehci_ready (ehci);
	if (in_interrupt ()) {		/* must not happen!! */
		ehci_err (ehci, "stopped in_interrupt!\n");
		return;
	}
	del_timer_sync (&ehci->watchdog);

	/* Turn off port power on all root hub ports. */
	rh_ports = HCS_N_PORTS (ehci->hcs_params);
	for (port = 1; port <= rh_ports; port++) {
		ehci_hub_control(hcd, ClearPortFeature, USB_PORT_FEAT_POWER,
			port, NULL, 0);
	}

	ehci_reset (ehci);
	writel (0, &ehci->regs->intr_enable);

	/* let companion controllers work when we aren't */
	writel (0, &ehci->regs->configured_flag);
	unregister_reboot_notifier (&ehci->reboot_notifier);

	remove_debug_files (ehci);

	/* root hub is shut down separately (first, when possible) */
	spin_lock_irq (&ehci->lock);
	if (ehci->async)
		ehci_work (ehci, NULL);
	spin_unlock_irq (&ehci->lock);
	ehci_mem_cleanup (ehci);

#ifdef	EHCI_STATS
	ehci_dbg (ehci, "irq normal %ld err %ld reclaim %ld (lost %ld)\n",
		ehci->stats.normal, ehci->stats.error, ehci->stats.reclaim,
		ehci->stats.lost_iaa);
	ehci_dbg (ehci, "complete %ld unlink %ld\n",
		ehci->stats.complete, ehci->stats.unlink);
#endif

	dbg_status (ehci, "ehci_stop completed", readl (&ehci->regs->status));
}

static int ehci_get_frame (struct usb_hcd *hcd)
{
	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
	return (readl (&ehci->regs->frame_index) >> 3) % ehci->periodic_size;
}

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

#ifdef	CONFIG_PM

/* suspend/resume, section 4.3 */

/* These routines rely on PCI to handle powerdown and wakeup, and
 * transceivers that don't need any software attention to set up
 * the right sort of wakeup.  
 */

static int ehci_suspend (struct usb_hcd *hcd, u32 state)
{
	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);

	while (time_before (jiffies, ehci->next_statechange))
		msleep (100);

#ifdef	CONFIG_USB_SUSPEND
	(void) usb_suspend_device (hcd->self.root_hub, state);
#else
	/* FIXME lock root hub */
	(void) ehci_hub_suspend (hcd);
#endif

	// save (PCI) FLADJ in case of Vaux power loss

	return 0;
}

static int ehci_resume (struct usb_hcd *hcd)
{
	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
	int			retval;

	// maybe restore (PCI) FLADJ

	while (time_before (jiffies, ehci->next_statechange))
		msleep (100);

#ifdef	CONFIG_USB_SUSPEND
	retval = usb_resume_device (hcd->self.root_hub);
#else
	/* FIXME lock root hub */
	retval = ehci_hub_resume (hcd);
#endif
	if (retval == 0)
		hcd->self.controller->power.power_state = 0;
	return retval;
}

#endif

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

/*
 * ehci_work is called from some interrupts, timers, and so on.
 * it calls driver completion functions, after dropping ehci->lock.
 */
static void ehci_work (struct ehci_hcd *ehci, struct pt_regs *regs)
{
	timer_action_done (ehci, TIMER_IO_WATCHDOG);
	if (ehci->reclaim_ready)
		end_unlink_async (ehci, regs);
	scan_async (ehci, regs);
	if (ehci->next_uframe != -1)
		scan_periodic (ehci, regs);

	/* the IO watchdog guards against hardware or driver bugs that
	 * misplace IRQs, and should let us run completely without IRQs.
	 * such lossage has been observed on both VT6202 and VT8235. 
	 */
	if ((ehci->async->qh_next.ptr != 0) || (ehci->periodic_sched != 0))
		timer_action (ehci, TIMER_IO_WATCHDOG);
}

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

static irqreturn_t ehci_irq (struct usb_hcd *hcd, struct pt_regs *regs)
{
	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
	u32			status;
	int			bh;

	spin_lock (&ehci->lock);

	status = readl (&ehci->regs->status);

	/* e.g. cardbus physical eject */
	if (status == ~(u32) 0) {
		ehci_dbg (ehci, "device removed\n");
		goto dead;
	}

	status &= INTR_MASK;
	if (!status) {			/* irq sharing? */
		spin_unlock(&ehci->lock);
		return IRQ_NONE;
	}

	/* clear (just) interrupts */
	writel (status, &ehci->regs->status);
	readl (&ehci->regs->command);	/* unblock posted write */
	bh = 0;

#ifdef	EHCI_VERBOSE_DEBUG
	/* unrequested/ignored: Frame List Rollover */
	dbg_status (ehci, "irq", status);
#endif

	/* INT, ERR, and IAA interrupt rates can be throttled */

	/* normal [4.15.1.2] or error [4.15.1.1] completion */
	if (likely ((status & (STS_INT|STS_ERR)) != 0)) {
		if (likely ((status & STS_ERR) == 0))
			COUNT (ehci->stats.normal);
		else
			COUNT (ehci->stats.error);
		bh = 1;
	}

	/* complete the unlinking of some qh [4.15.2.3] */
	if (status & STS_IAA) {
		COUNT (ehci->stats.reclaim);
		ehci->reclaim_ready = 1;
		bh = 1;
	}

	/* remote wakeup [4.3.1] */
	if ((status & STS_PCD) && ehci->hcd.remote_wakeup) {
		unsigned	i = HCS_N_PORTS (ehci->hcs_params);

		/* resume root hub? */
		status = readl (&ehci->regs->command);
		if (!(status & CMD_RUN))
			writel (status | CMD_RUN, &ehci->regs->command);

		while (i--) {
			status = readl (&ehci->regs->port_status [i]);
			if (status & PORT_OWNER)
				continue;
			if (!(status & PORT_RESUME)
					|| ehci->reset_done [i] != 0)
				continue;

			/* start 20 msec resume signaling from this port,
			 * and make khubd collect PORT_STAT_C_SUSPEND to
			 * stop that signaling.
			 */
			ehci->reset_done [i] = jiffies + msecs_to_jiffies (20);
			mod_timer (&ehci->hcd.rh_timer,
					ehci->reset_done [i] + 1);
			ehci_dbg (ehci, "port %d remote wakeup\n", i + 1);
		}
	}

	/* PCI errors [4.15.2.4] */
	if (unlikely ((status & STS_FATAL) != 0)) {
		ehci_err (ehci, "fatal error\n");
dead:
		ehci_reset (ehci);
		/* generic layer kills/unlinks all urbs, then
		 * uses ehci_stop to clean up the rest
		 */
		bh = 1;
	}

	if (bh)
		ehci_work (ehci, regs);
	spin_unlock (&ehci->lock);
	return IRQ_HANDLED;
}

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

/*
 * non-error returns are a promise to giveback() the urb later
 * we drop ownership so next owner (or urb unlink) can get it
 *
 * urb + dev is in hcd.self.controller.urb_list
 * we're queueing TDs onto software and hardware lists
 *
 * hcd-specific init for hcpriv hasn't been done yet
 *
 * NOTE:  control, bulk, and interrupt share the same code to append TDs
 * to a (possibly active) QH, and the same QH scanning code.
 */
static int ehci_urb_enqueue (
	struct usb_hcd	*hcd,
	struct urb	*urb,
	int		mem_flags
) {
	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
	struct list_head	qtd_list;

	INIT_LIST_HEAD (&qtd_list);

	switch (usb_pipetype (urb->pipe)) {
	// case PIPE_CONTROL:
	// case PIPE_BULK:
	default:
		if (!qh_urb_transaction (ehci, urb, &qtd_list, mem_flags))
			return -ENOMEM;
		return submit_async (ehci, urb, &qtd_list, mem_flags);

	case PIPE_INTERRUPT:
		if (!qh_urb_transaction (ehci, urb, &qtd_list, mem_flags))
			return -ENOMEM;
		return intr_submit (ehci, urb, &qtd_list, mem_flags);

	case PIPE_ISOCHRONOUS:
		if (urb->dev->speed == USB_SPEED_HIGH)
			return itd_submit (ehci, urb, mem_flags);
		else
			return sitd_submit (ehci, urb, mem_flags);
	}
}

/* remove from hardware lists
 * completions normally happen asynchronously
 */

static int ehci_urb_dequeue (struct usb_hcd *hcd, struct urb *urb)
{
	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
	struct ehci_qh		*qh;
	unsigned long		flags;

	spin_lock_irqsave (&ehci->lock, flags);
	switch (usb_pipetype (urb->pipe)) {
	// case PIPE_CONTROL:
	// case PIPE_BULK:
	default:
		qh = (struct ehci_qh *) urb->hcpriv;
		if (!qh)
			break;

		/* if we need to use IAA and it's busy, defer */
		if (qh->qh_state == QH_STATE_LINKED
				&& ehci->reclaim
				&& HCD_IS_RUNNING (ehci->hcd.state)
				) {
			struct ehci_qh		*last;

			for (last = ehci->reclaim;
					last->reclaim;
					last = last->reclaim)
				continue;
			qh->qh_state = QH_STATE_UNLINK_WAIT;
			last->reclaim = qh;

		/* bypass IAA if the hc can't care */
		} else if (!HCD_IS_RUNNING (ehci->hcd.state) && ehci->reclaim)
			end_unlink_async (ehci, NULL);

		/* something else might have unlinked the qh by now */
		if (qh->qh_state == QH_STATE_LINKED)
			start_unlink_async (ehci, qh);
		break;

	case PIPE_INTERRUPT:
		qh = (struct ehci_qh *) urb->hcpriv;
		if (!qh)
			break;
		if (qh->qh_state == QH_STATE_LINKED) {
			/* messy, can spin or block a microframe ... */
			intr_deschedule (ehci, qh, 1);
			/* qh_state == IDLE */
		}
		qh_completions (ehci, qh, NULL);

		/* reschedule QH iff another request is queued */
		if (!list_empty (&qh->qtd_list)
				&& HCD_IS_RUNNING (ehci->hcd.state)) {
			int status;

			status = qh_schedule (ehci, qh);
			spin_unlock_irqrestore (&ehci->lock, flags);

			if (status != 0) {
				// shouldn't happen often, but ...
				// FIXME kill those tds' urbs
				err ("can't reschedule qh %p, err %d",
					qh, status);
			}
			return status;
		}
		break;

	case PIPE_ISOCHRONOUS:
		// itd or sitd ...

		// wait till next completion, do it then.
		// completion irqs can wait up to 1024 msec,
		break;
	}
	spin_unlock_irqrestore (&ehci->lock, flags);
	return 0;
}

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

// bulk qh holds the data toggle

static void
ehci_endpoint_disable (struct usb_hcd *hcd, struct hcd_dev *dev, int ep)
{
	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
	int			epnum;
	unsigned long		flags;
	struct ehci_qh		*qh;

	/* ASSERT:  any requests/urbs are being unlinked */
	/* ASSERT:  nobody can be submitting urbs for this any more */

	epnum = ep & USB_ENDPOINT_NUMBER_MASK;
	if (epnum != 0 && (ep & USB_DIR_IN))
		epnum |= 0x10;

rescan:
	spin_lock_irqsave (&ehci->lock, flags);
	qh = (struct ehci_qh *) dev->ep [epnum];
	if (!qh)
		goto done;

	/* endpoints can be iso streams.  for now, we don't
	 * accelerate iso completions ... so spin a while.
	 */
	if (qh->hw_info1 == 0) {
		ehci_vdbg (ehci, "iso delay\n");
		goto idle_timeout;
	}

	if (!HCD_IS_RUNNING (ehci->hcd.state))
		qh->qh_state = QH_STATE_IDLE;
	switch (qh->qh_state) {
	case QH_STATE_UNLINK:		/* wait for hw to finish? */
idle_timeout:
		spin_unlock_irqrestore (&ehci->lock, flags);
		set_current_state (TASK_UNINTERRUPTIBLE);
		schedule_timeout (1);
		goto rescan;
	case QH_STATE_IDLE:		/* fully unlinked */
		if (list_empty (&qh->qtd_list)) {
			qh_put (qh);
			break;
		}
		/* else FALL THROUGH */
	default:
		/* caller was supposed to have unlinked any requests;
		 * that's not our job.  just leak this memory.
		 */
		ehci_err (ehci, "qh %p (#%d) state %d%s\n",
			qh, epnum, qh->qh_state,
			list_empty (&qh->qtd_list) ? "" : "(has tds)");
		break;
	}
	dev->ep[epnum] = NULL;
done:
	spin_unlock_irqrestore (&ehci->lock, flags);
	return;
}

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

static const struct hc_driver ehci_driver = {
	.description =		hcd_name,

	/*
	 * generic hardware linkage
	 */
	.irq =			ehci_irq,
	.flags =		HCD_MEMORY | HCD_USB2,

	/*
	 * basic lifecycle operations
	 */
	.reset =		ehci_hc_reset,
	.start =		ehci_start,
#ifdef	CONFIG_PM
	.suspend =		ehci_suspend,
	.resume =		ehci_resume,
#endif
	.stop =			ehci_stop,

	/*
	 * memory lifecycle (except per-request)
	 */
	.hcd_alloc =		ehci_hcd_alloc,
	.hcd_free =		ehci_hcd_free,

	/*
	 * managing i/o requests and associated device resources
	 */
	.urb_enqueue =		ehci_urb_enqueue,
	.urb_dequeue =		ehci_urb_dequeue,
	.endpoint_disable =	ehci_endpoint_disable,

	/*
	 * scheduling support
	 */
	.get_frame_number =	ehci_get_frame,

	/*
	 * root hub support
	 */
	.hub_status_data =	ehci_hub_status_data,
	.hub_control =		ehci_hub_control,
	.hub_suspend =		ehci_hub_suspend,
	.hub_resume =		ehci_hub_resume,
};

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

/* EHCI 1.0 doesn't require PCI */

#ifdef	CONFIG_PCI

/* PCI driver selection metadata; PCI hotplugging uses this */
static const struct pci_device_id pci_ids [] = { {
	/* handle any USB 2.0 EHCI controller */
	PCI_DEVICE_CLASS(((PCI_CLASS_SERIAL_USB << 8) | 0x20), ~0),
	.driver_data =	(unsigned long) &ehci_driver,
	},
	{ /* end: all zeroes */ }
};
MODULE_DEVICE_TABLE (pci, pci_ids);

/* pci driver glue; this is a "new style" PCI driver module */
static struct pci_driver ehci_pci_driver = {
	.name =		(char *) hcd_name,
	.id_table =	pci_ids,

	.probe =	usb_hcd_pci_probe,
	.remove =	usb_hcd_pci_remove,

#ifdef	CONFIG_PM
	.suspend =	usb_hcd_pci_suspend,
	.resume =	usb_hcd_pci_resume,
#endif
};

#endif	/* PCI */


#define DRIVER_INFO DRIVER_VERSION " " DRIVER_DESC

MODULE_DESCRIPTION (DRIVER_INFO);
MODULE_AUTHOR (DRIVER_AUTHOR);
MODULE_LICENSE ("GPL");

static int __init init (void) 
{
	if (usb_disabled())
		return -ENODEV;

	pr_debug ("%s: block sizes: qh %Zd qtd %Zd itd %Zd sitd %Zd\n",
		hcd_name,
		sizeof (struct ehci_qh), sizeof (struct ehci_qtd),
		sizeof (struct ehci_itd), sizeof (struct ehci_sitd));

	return pci_module_init (&ehci_pci_driver);
}
module_init (init);

static void __exit cleanup (void) 
{	
	pci_unregister_driver (&ehci_pci_driver);
}
module_exit (cleanup);