hub.c

Linux Kernel 2.6.9 for OMAP1710

		case 0x10:
		case 0x18:
			dev_dbg(hub_dev, "no over-current protection\n");
                        break;
	}

	spin_lock_init (&hub->tt.lock);
	INIT_LIST_HEAD (&hub->tt.clear_list);
	INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
	switch (hdev->descriptor.bDeviceProtocol) {
		case 0:
			break;
		case 1:
			dev_dbg(hub_dev, "Single TT\n");
			hub->tt.hub = hdev;
			break;
		case 2:
			ret = usb_set_interface(hdev, 0, 1);
			if (ret == 0) {
				dev_dbg(hub_dev, "TT per port\n");
				hub->tt.multi = 1;
			} else
				dev_err(hub_dev, "Using single TT (err %d)\n",
					ret);
			hub->tt.hub = hdev;
			break;
		default:
			dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
				hdev->descriptor.bDeviceProtocol);
			break;
	}

	switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_TTTT) {
		case 0x00:
			if (hdev->descriptor.bDeviceProtocol != 0)
				dev_dbg(hub_dev, "TT requires at most 8 FS bit times\n");
			break;
		case 0x20:
			dev_dbg(hub_dev, "TT requires at most 16 FS bit times\n");
			break;
		case 0x40:
			dev_dbg(hub_dev, "TT requires at most 24 FS bit times\n");
			break;
		case 0x60:
			dev_dbg(hub_dev, "TT requires at most 32 FS bit times\n");
			break;
	}

	/* probe() zeroes hub->indicator[] */
	if (hub->descriptor->wHubCharacteristics & HUB_CHAR_PORTIND) {
		hub->has_indicators = 1;
		dev_dbg(hub_dev, "Port indicators are supported\n");
	}

	dev_dbg(hub_dev, "power on to power good time: %dms\n",
		hub->descriptor->bPwrOn2PwrGood * 2);

	/* power budgeting mostly matters with bus-powered hubs,
	 * and battery-powered root hubs (may provide just 8 mA).
	 */
	ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
	if (ret < 0) {
		message = "can't get hub status";
		goto fail;
	}
	cpu_to_le16s(&hubstatus);
	if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
		dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
			hub->descriptor->bHubContrCurrent);
		hub->power_budget = (501 - hub->descriptor->bHubContrCurrent)
					/ 2;
		dev_dbg(hub_dev, "%dmA bus power budget for children\n",
			hub->power_budget * 2);
	}


	ret = hub_hub_status(hub, &hubstatus, &hubchange);
	if (ret < 0) {
		message = "can't get hub status";
		goto fail;
	}

	/* local power status reports aren't always correct */
	if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
		dev_dbg(hub_dev, "local power source is %s\n",
			(hubstatus & HUB_STATUS_LOCAL_POWER)
			? "lost (inactive)" : "good");

	if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) == 0)
		dev_dbg(hub_dev, "%sover-current condition exists\n",
			(hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");

	/* Start the interrupt endpoint */
	pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
	maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));

	if (maxp > sizeof(*hub->buffer))
		maxp = sizeof(*hub->buffer);

	hub->urb = usb_alloc_urb(0, GFP_KERNEL);
	if (!hub->urb) {
		message = "couldn't allocate interrupt urb";
		ret = -ENOMEM;
		goto fail;
	}

	usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
		hub, endpoint->bInterval);
	hub->urb->transfer_dma = hub->buffer_dma;
	hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
	ret = usb_submit_urb(hub->urb, GFP_KERNEL);
	if (ret) {
		message = "couldn't submit status urb";
		goto fail;
	}

	/* Wake up khubd */
	wake_up(&khubd_wait);

	/* maybe start cycling the hub leds */
	if (hub->has_indicators && blinkenlights) {
		set_port_led(hdev, 1, HUB_LED_GREEN);
		hub->indicator [0] = INDICATOR_CYCLE;
		schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
	}

	hub_power_on(hub);

	return 0;

fail:
	dev_err (hub_dev, "config failed, %s (err %d)\n",
			message, ret);
	/* hub_disconnect() frees urb and descriptor */
	return ret;
}

static unsigned highspeed_hubs;

static void hub_quiesce(struct usb_hub *hub)
{
	/* stop khubd and related activity */
	hub->quiescing = 1;
	usb_kill_urb(hub->urb);
	if (hub->has_indicators)
		cancel_delayed_work(&hub->leds);
	if (hub->has_indicators || hub->tt.hub)
		flush_scheduled_work();
}

#ifdef	CONFIG_USB_SUSPEND

static void hub_reactivate(struct usb_hub *hub)
{
	int	status;

	hub->quiescing = 0;
	status = usb_submit_urb(hub->urb, GFP_NOIO);
	if (status < 0)
		dev_err(&hub->intf->dev, "reactivate --> %d\n", status);
	if (hub->has_indicators && blinkenlights)
		schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
}

#endif

static void hub_disconnect(struct usb_interface *intf)
{
	struct usb_hub *hub = usb_get_intfdata (intf);
	struct usb_device *hdev;

	if (!hub)
		return;
	hdev = hub->hdev;

	if (hdev->speed == USB_SPEED_HIGH)
		highspeed_hubs--;

	usb_set_intfdata (intf, NULL);

	hub_quiesce(hub);
	usb_free_urb(hub->urb);
	hub->urb = NULL;

	spin_lock_irq(&hub_event_lock);
	list_del_init(&hub->event_list);
	spin_unlock_irq(&hub_event_lock);

	if (hub->descriptor) {
		kfree(hub->descriptor);
		hub->descriptor = NULL;
	}

	if (hub->status) {
		kfree(hub->status);
		hub->status = NULL;
	}

	if (hub->buffer) {
		usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
				hub->buffer_dma);
		hub->buffer = NULL;
	}

	/* Free the memory */
	kfree(hub);
}

static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
	struct usb_host_interface *desc;
	struct usb_endpoint_descriptor *endpoint;
	struct usb_device *hdev;
	struct usb_hub *hub;
	struct device *hub_dev;

	desc = intf->cur_altsetting;
	hdev = interface_to_usbdev(intf);
	hub_dev = &intf->dev;

	/* Some hubs have a subclass of 1, which AFAICT according to the */
	/*  specs is not defined, but it works */
	if ((desc->desc.bInterfaceSubClass != 0) &&
	    (desc->desc.bInterfaceSubClass != 1)) {
descriptor_error:
		dev_err (hub_dev, "bad descriptor, ignoring hub\n");
		return -EIO;
	}

	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
	if (desc->desc.bNumEndpoints != 1)
		goto descriptor_error;

	endpoint = &desc->endpoint[0].desc;

	/* Output endpoint? Curiouser and curiouser.. */
	if (!(endpoint->bEndpointAddress & USB_DIR_IN))
		goto descriptor_error;

	/* If it's not an interrupt endpoint, we'd better punt! */
	if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
			!= USB_ENDPOINT_XFER_INT)
		goto descriptor_error;

	/* We found a hub */
	dev_info (hub_dev, "USB hub found\n");

	hub = kmalloc(sizeof(*hub), GFP_KERNEL);
	if (!hub) {
		dev_dbg (hub_dev, "couldn't kmalloc hub struct\n");
		return -ENOMEM;
	}

	memset(hub, 0, sizeof(*hub));

	INIT_LIST_HEAD(&hub->event_list);
	hub->intf = intf;
	hub->hdev = hdev;
	INIT_WORK(&hub->leds, led_work, hub);

	usb_set_intfdata (intf, hub);

	if (hdev->speed == USB_SPEED_HIGH)
		highspeed_hubs++;

	if (hub_configure(hub, endpoint) >= 0)
		return 0;

	hub_disconnect (intf);
	return -ENODEV;
}

static int
hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
{
	struct usb_device *hdev = interface_to_usbdev (intf);

	/* assert ifno == 0 (part of hub spec) */
	switch (code) {
	case USBDEVFS_HUB_PORTINFO: {
		struct usbdevfs_hub_portinfo *info = user_data;
		unsigned long flags;
		int i;

		spin_lock_irqsave(&hub_event_lock, flags);
		if (hdev->devnum <= 0)
			info->nports = 0;
		else {
			info->nports = hdev->maxchild;
			for (i = 0; i < info->nports; i++) {
				if (hdev->children[i] == NULL)
					info->port[i] = 0;
				else
					info->port[i] =
						hdev->children[i]->devnum;
			}
		}
		spin_unlock_irqrestore(&hub_event_lock, flags);

		return info->nports + 1;
		}

	default:
		return -ENOSYS;
	}
}

/* caller has locked the hub and must own the device lock */
static int hub_reset(struct usb_hub *hub)
{
	struct usb_device *hdev = hub->hdev;
	int i;

	/* Disconnect any attached devices */
	for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
		if (hdev->children[i])
			usb_disconnect(&hdev->children[i]);
	}

	/* Attempt to reset the hub */
	if (hub->urb)
		usb_kill_urb(hub->urb);
	else
		return -1;

	if (__usb_reset_device(hdev))
		return -1;

	hub->urb->dev = hdev;                                                    
	if (usb_submit_urb(hub->urb, GFP_KERNEL))
		return -1;

	hub_power_on(hub);

	return 0;
}

/* caller has locked the hub */
/* FIXME!  This routine should be subsumed into hub_reset */
static void hub_start_disconnect(struct usb_device *hdev)
{
	struct usb_device *parent = hdev->parent;
	int i;

	/* Find the device pointer to disconnect */
	if (parent) {
		for (i = 0; i < parent->maxchild; i++) {
			if (parent->children[i] == hdev) {
				usb_disconnect(&parent->children[i]);
				return;
			}
		}
	}

	dev_err(&hdev->dev, "cannot disconnect hub!\n");
}


static void recursively_mark_NOTATTACHED(struct usb_device *udev)
{
	int i;

	for (i = 0; i < udev->maxchild; ++i) {
		if (udev->children[i])
			recursively_mark_NOTATTACHED(udev->children[i]);
	}
	udev->state = USB_STATE_NOTATTACHED;
}

/* grab device/port lock, returning index of that port (zero based).
 * protects the upstream link used by this device from concurrent
 * tree operations like suspend, resume, reset, and disconnect, which
 * apply to everything downstream of a given port.
 */
static int locktree(struct usb_device *udev)
{
	int			t;
	struct usb_device	*hdev;

	if (!udev)
		return -ENODEV;

	/* root hub is always the first lock in the series */
	hdev = udev->parent;
	if (!hdev) {
		down(&udev->serialize);
		return 0;
	}

	/* on the path from root to us, lock everything from
	 * top down, dropping parent locks when not needed
	 *
	 * NOTE: if disconnect were to ignore the locking, we'd need
	 * to get extra refcounts to everything since hdev->children
	 * and udev->parent could be invalidated while we work...
	 */
	t = locktree(hdev);
	if (t < 0)
		return t;
	spin_lock_irq(&device_state_lock);
	for (t = 0; t < hdev->maxchild; t++) {
		if (hdev->children[t] == udev) {
			/* everything is fail-fast once disconnect
			 * processing starts
			 */
			if (udev->state == USB_STATE_NOTATTACHED)
				break;

			/* when everyone grabs locks top->bottom,
			 * non-overlapping work may be concurrent
			 */
			spin_unlock_irq(&device_state_lock);
			down(&udev->serialize);
			up(&hdev->serialize);
			return t;
		}
	}
	spin_unlock_irq(&device_state_lock);
	up(&hdev->serialize);
	return -ENODEV;
}

/**
 * usb_set_device_state - change a device's current state (usbcore-internal)
 * @udev: pointer to device whose state should be changed
 * @new_state: new state value to be stored
 *
 * udev->state is _not_ protected by the device lock.  This
 * is so that devices can be marked as disconnected as soon as possible,
 * without having to wait for the semaphore to be released.  Instead,
 * changes to the state must be protected by the device_state_lock spinlock.
 *
 * Once a device has been added to the device tree, all changes to its state
 * should be made using this routine.  The state should _not_ be set directly.
 *
 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
 * Otherwise udev->state is set to new_state, and if new_state is
 * USB_STATE_NOTATTACHED then all of udev's descendant's states are also set
 * to USB_STATE_NOTATTACHED.
 */
void usb_set_device_state(struct usb_device *udev,
		enum usb_device_state new_state)
{
	unsigned long flags;

	spin_lock_irqsave(&device_state_lock, flags);
	if (udev->state == USB_STATE_NOTATTACHED)
		;	/* do nothing */
	else if (new_state != USB_STATE_NOTATTACHED)
		udev->state = new_state;
	else
		recursively_mark_NOTATTACHED(udev);
	spin_unlock_irqrestore(&device_state_lock, flags);
}


static void choose_address(struct usb_device *udev)
{
	int		devnum;
	struct usb_bus	*bus = udev->bus;

	/* If khubd ever becomes multithreaded, this will need a lock */

	/* Try to allocate the next devnum beginning at bus->devnum_next. */
	devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
			bus->devnum_next);
	if (devnum >= 128)
		devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);

	bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);

	if (devnum < 128) {
		set_bit(devnum, bus->devmap.devicemap);
		udev->devnum = devnum;
	}
}

static void release_address(struct usb_device *udev)
{
	if (udev->devnum > 0) {
		clear_bit(udev->devnum, udev->bus->devmap.devicemap);
		udev->devnum = -1;
	}
}

/**
 * usb_disconnect - disconnect a device (usbcore-internal)
 * @pdev: pointer to device being disconnected, into a locked hub
 * Context: !in_interrupt ()