hcd.c

来自「omap3 linux 2.6 用nocc去除了冗余代码」· C语言 代码 · 共 1,743 行 · 第 1/4 页

/**
 * usb_hcd_resume_root_hub - called by HCD to resume its root hub 
 * @hcd: host controller for this root hub
 *
 * The USB host controller calls this function when its root hub is
 * suspended (with the remote wakeup feature enabled) and a remote
 * wakeup request is received.  The routine submits a workqueue request
 * to resume the root hub (that is, manage its downstream ports again).
 */
void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
{
	unsigned long flags;

	spin_lock_irqsave (&hcd_root_hub_lock, flags);
	if (hcd->rh_registered)
		queue_work(ksuspend_usb_wq, &hcd->wakeup_work);
	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
}
EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);


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


/**
 * usb_bus_start_enum - start immediate enumeration (for OTG)
 * @bus: the bus (must use hcd framework)
 * @port_num: 1-based number of port; usually bus->otg_port
 * Context: in_interrupt()
 *
 * Starts enumeration, with an immediate reset followed later by
 * khubd identifying and possibly configuring the device.
 * This is needed by OTG controller drivers, where it helps meet
 * HNP protocol timing requirements for starting a port reset.
 */
int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
{
	struct usb_hcd		*hcd;
	int			status = -EOPNOTSUPP;

	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
	 * boards with root hubs hooked up to internal devices (instead of
	 * just the OTG port) may need more attention to resetting...
	 */
	hcd = container_of (bus, struct usb_hcd, self);
	if (port_num && hcd->driver->start_port_reset)
		status = hcd->driver->start_port_reset(hcd, port_num);

	/* run khubd shortly after (first) root port reset finishes;
	 * it may issue others, until at least 50 msecs have passed.
	 */
	if (status == 0)
		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
	return status;
}
EXPORT_SYMBOL (usb_bus_start_enum);


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

/**
 * usb_hcd_giveback_urb - return URB from HCD to device driver
 * @hcd: host controller returning the URB
 * @urb: urb being returned to the USB device driver.
 * Context: in_interrupt()
 *
 * This hands the URB from HCD to its USB device driver, using its
 * completion function.  The HCD has freed all per-urb resources
 * (and is done using urb->hcpriv).  It also released all HCD locks;
 * the device driver won't cause problems if it frees, modifies,
 * or resubmits this URB.
 */
void usb_hcd_giveback_urb (struct usb_hcd *hcd, struct urb *urb)
{
	int at_root_hub;

	at_root_hub = (urb->dev == hcd->self.root_hub);
	urb_unlink (urb);

	/* lower level hcd code should use *_dma exclusively if the
	 * host controller does DMA */
	if (hcd->self.uses_dma && !at_root_hub) {
		if (usb_pipecontrol (urb->pipe)
			&& !(urb->transfer_flags & URB_NO_SETUP_DMA_MAP))
			dma_unmap_single (hcd->self.controller, urb->setup_dma,
					sizeof (struct usb_ctrlrequest),
					DMA_TO_DEVICE);
		if (urb->transfer_buffer_length != 0
			&& !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP))
			dma_unmap_single (hcd->self.controller, 
					urb->transfer_dma,
					urb->transfer_buffer_length,
					usb_pipein (urb->pipe)
					    ? DMA_FROM_DEVICE
					    : DMA_TO_DEVICE);
	}

	usbmon_urb_complete (&hcd->self, urb);
	/* pass ownership to the completion handler */
	urb->complete (urb);
	atomic_dec (&urb->use_count);
	if (unlikely (urb->reject))
		wake_up (&usb_kill_urb_queue);
	usb_put_urb (urb);
}
EXPORT_SYMBOL (usb_hcd_giveback_urb);

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

/**
 * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
 * @irq: the IRQ being raised
 * @__hcd: pointer to the HCD whose IRQ is being signaled
 * @r: saved hardware registers
 *
 * If the controller isn't HALTed, calls the driver's irq handler.
 * Checks whether the controller is now dead.
 */
irqreturn_t usb_hcd_irq (int irq, void *__hcd)
{
	struct usb_hcd		*hcd = __hcd;
	int			start = hcd->state;

	if (unlikely(start == HC_STATE_HALT ||
	    !test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)))
		return IRQ_NONE;
	if (hcd->driver->irq (hcd) == IRQ_NONE)
		return IRQ_NONE;

	set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);

	if (unlikely(hcd->state == HC_STATE_HALT))
		usb_hc_died (hcd);
	return IRQ_HANDLED;
}

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

/**
 * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
 * @hcd: pointer to the HCD representing the controller
 *
 * This is called by bus glue to report a USB host controller that died
 * while operations may still have been pending.  It's called automatically
 * by the PCI glue, so only glue for non-PCI busses should need to call it. 
 */
void usb_hc_died (struct usb_hcd *hcd)
{
	unsigned long flags;

	dev_err (hcd->self.controller, "HC died; cleaning up\n");

	spin_lock_irqsave (&hcd_root_hub_lock, flags);
	if (hcd->rh_registered) {
		hcd->poll_rh = 0;

		/* make khubd clean up old urbs and devices */
		usb_set_device_state (hcd->self.root_hub,
				USB_STATE_NOTATTACHED);
		usb_kick_khubd (hcd->self.root_hub);
	}
	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
}
EXPORT_SYMBOL_GPL (usb_hc_died);

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

/**
 * usb_create_hcd - create and initialize an HCD structure
 * @driver: HC driver that will use this hcd
 * @dev: device for this HC, stored in hcd->self.controller
 * @bus_name: value to store in hcd->self.bus_name
 * Context: !in_interrupt()
 *
 * Allocate a struct usb_hcd, with extra space at the end for the
 * HC driver's private data.  Initialize the generic members of the
 * hcd structure.
 *
 * If memory is unavailable, returns NULL.
 */
struct usb_hcd *usb_create_hcd (const struct hc_driver *driver,
		struct device *dev, char *bus_name)
{
	struct usb_hcd *hcd;

	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
	if (!hcd) {
		dev_dbg (dev, "hcd alloc failed\n");
		return NULL;
	}
	dev_set_drvdata(dev, hcd);
	kref_init(&hcd->kref);

	usb_bus_init(&hcd->self);
	hcd->self.controller = dev;
	hcd->self.bus_name = bus_name;
	hcd->self.uses_dma = (dev->dma_mask != NULL);

	init_timer(&hcd->rh_timer);
	hcd->rh_timer.function = rh_timer_func;
	hcd->rh_timer.data = (unsigned long) hcd;
	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);

	hcd->driver = driver;
	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
			"USB Host Controller";

	return hcd;
}
EXPORT_SYMBOL (usb_create_hcd);

static void hcd_release (struct kref *kref)
{
	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);

	kfree(hcd);
}

struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
{
	if (hcd)
		kref_get (&hcd->kref);
	return hcd;
}
EXPORT_SYMBOL (usb_get_hcd);

void usb_put_hcd (struct usb_hcd *hcd)
{
	if (hcd)
		kref_put (&hcd->kref, hcd_release);
}
EXPORT_SYMBOL (usb_put_hcd);

/**
 * usb_add_hcd - finish generic HCD structure initialization and register
 * @hcd: the usb_hcd structure to initialize
 * @irqnum: Interrupt line to allocate
 * @irqflags: Interrupt type flags
 *
 * Finish the remaining parts of generic HCD initialization: allocate the
 * buffers of consistent memory, register the bus, request the IRQ line,
 * and call the driver's reset() and start() routines.
 */
int usb_add_hcd(struct usb_hcd *hcd,
		unsigned int irqnum, unsigned long irqflags)
{
	int retval;
	struct usb_device *rhdev;

	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);

	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);

	/* HC is in reset state, but accessible.  Now do the one-time init,
	 * bottom up so that hcds can customize the root hubs before khubd
	 * starts talking to them.  (Note, bus id is assigned early too.)
	 */
	if ((retval = hcd_buffer_create(hcd)) != 0) {
		dev_dbg(hcd->self.controller, "pool alloc failed\n");
		return retval;
	}

	if ((retval = usb_register_bus(&hcd->self)) < 0)
		goto err_register_bus;

	if ((rhdev = usb_alloc_dev(NULL, &hcd->self, 0)) == NULL) {
		dev_err(hcd->self.controller, "unable to allocate root hub\n");
		retval = -ENOMEM;
		goto err_allocate_root_hub;
	}
	rhdev->speed = (hcd->driver->flags & HCD_USB2) ? USB_SPEED_HIGH :
			USB_SPEED_FULL;
	hcd->self.root_hub = rhdev;

	/* wakeup flag init defaults to "everything works" for root hubs,
	 * but drivers can override it in reset() if needed, along with
	 * recording the overall controller's system wakeup capability.
	 */
	device_init_wakeup(&rhdev->dev, 1);

	/* "reset" is misnamed; its role is now one-time init. the controller
	 * should already have been reset (and boot firmware kicked off etc).
	 */
	if (hcd->driver->reset && (retval = hcd->driver->reset(hcd)) < 0) {
		dev_err(hcd->self.controller, "can't setup\n");
		goto err_hcd_driver_setup;
	}

	/* NOTE: root hub and controller capabilities may not be the same */
	if (device_can_wakeup(hcd->self.controller)
			&& device_can_wakeup(&hcd->self.root_hub->dev))
		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");

	/* enable irqs just before we start the controller */
	if (hcd->driver->irq) {
		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
				hcd->driver->description, hcd->self.busnum);
		if ((retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
				hcd->irq_descr, hcd)) != 0) {
			dev_err(hcd->self.controller,
					"request interrupt %d failed\n", irqnum);
			goto err_request_irq;
		}
		hcd->irq = irqnum;
		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
				(hcd->driver->flags & HCD_MEMORY) ?
					"io mem" : "io base",
					(unsigned long long)hcd->rsrc_start);
	} else {
		hcd->irq = -1;
		if (hcd->rsrc_start)
			dev_info(hcd->self.controller, "%s 0x%08llx\n",
					(hcd->driver->flags & HCD_MEMORY) ?
					"io mem" : "io base",
					(unsigned long long)hcd->rsrc_start);
	}

	if ((retval = hcd->driver->start(hcd)) < 0) {
		dev_err(hcd->self.controller, "startup error %d\n", retval);
		goto err_hcd_driver_start;
	}

	/* starting here, usbcore will pay attention to this root hub */
	rhdev->bus_mA = min(500u, hcd->power_budget);
	if ((retval = register_root_hub(hcd)) != 0)
		goto err_register_root_hub;

	if (hcd->uses_new_polling && hcd->poll_rh)
		usb_hcd_poll_rh_status(hcd);
	return retval;

err_register_root_hub:
	hcd->driver->stop(hcd);
err_hcd_driver_start:
	if (hcd->irq >= 0)
		free_irq(irqnum, hcd);
err_request_irq:
err_hcd_driver_setup:
	hcd->self.root_hub = NULL;
	usb_put_dev(rhdev);
err_allocate_root_hub:
	usb_deregister_bus(&hcd->self);
err_register_bus:
	hcd_buffer_destroy(hcd);
	return retval;
} 
EXPORT_SYMBOL (usb_add_hcd);

/**
 * usb_remove_hcd - shutdown processing for generic HCDs
 * @hcd: the usb_hcd structure to remove
 * Context: !in_interrupt()
 *
 * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
 * invoking the HCD's stop() method.
 */
void usb_remove_hcd(struct usb_hcd *hcd)
{
	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);

	if (HC_IS_RUNNING (hcd->state))
		hcd->state = HC_STATE_QUIESCING;

	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
	spin_lock_irq (&hcd_root_hub_lock);
	hcd->rh_registered = 0;
	spin_unlock_irq (&hcd_root_hub_lock);

	cancel_work_sync(&hcd->wakeup_work);

	mutex_lock(&usb_bus_list_lock);
	usb_disconnect(&hcd->self.root_hub);
	mutex_unlock(&usb_bus_list_lock);

	hcd->driver->stop(hcd);
	hcd->state = HC_STATE_HALT;

	hcd->poll_rh = 0;
	del_timer_sync(&hcd->rh_timer);

	if (hcd->irq >= 0)
		free_irq(hcd->irq, hcd);
	usb_deregister_bus(&hcd->self);
	hcd_buffer_destroy(hcd);
}
EXPORT_SYMBOL (usb_remove_hcd);

void
usb_hcd_platform_shutdown(struct platform_device* dev)
{
	struct usb_hcd *hcd = platform_get_drvdata(dev);

	if (hcd->driver->shutdown)
		hcd->driver->shutdown(hcd);
}
EXPORT_SYMBOL (usb_hcd_platform_shutdown);

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


struct usb_mon_operations *mon_ops;

/*
 * The registration is unlocked.
 * We do it this way because we do not want to lock in hot paths.
 *
 * Notice that the code is minimally error-proof. Because usbmon needs
 * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
 */
 
int usb_mon_register (struct usb_mon_operations *ops)
{

	if (mon_ops)
		return -EBUSY;

	mon_ops = ops;
	mb();
	return 0;
}
EXPORT_SYMBOL_GPL (usb_mon_register);

void usb_mon_deregister (void)
{

	if (mon_ops == NULL) {
		printk(KERN_ERR "USB: monitor was not registered\n");
		return;
	}
	mon_ops = NULL;
	mb();
}
EXPORT_SYMBOL_GPL (usb_mon_deregister);