driver.c

omap3 linux 2.6 用nocc去除了冗余代码

 * that also specifies the vendor ID.  (Unforunately there isn't a
 * standard macro for creating records like this.)
 *
 * Within those groups, remember that not all combinations are
 * meaningful.  For example, don't give a product version range
 * without vendor and product IDs; or specify a protocol without
 * its associated class and subclass.
 */
const struct usb_device_id *usb_match_id(struct usb_interface *interface,
					 const struct usb_device_id *id)
{
	/* proc_connectinfo in devio.c may call us with id == NULL. */
	if (id == NULL)
		return NULL;

	/* It is important to check that id->driver_info is nonzero,
	   since an entry that is all zeroes except for a nonzero
	   id->driver_info is the way to create an entry that
	   indicates that the driver want to examine every
	   device and interface. */
	for (; id->idVendor || id->bDeviceClass || id->bInterfaceClass ||
	       id->driver_info; id++) {
		if (usb_match_one_id(interface, id))
			return id;
	}

	return NULL;
}
EXPORT_SYMBOL_GPL_FUTURE(usb_match_id);

static int usb_device_match(struct device *dev, struct device_driver *drv)
{
	/* devices and interfaces are handled separately */
	if (is_usb_device(dev)) {

		/* interface drivers never match devices */
		if (!is_usb_device_driver(drv))
			return 0;

		/* TODO: Add real matching code */
		return 1;

	} else {
		struct usb_interface *intf;
		struct usb_driver *usb_drv;
		const struct usb_device_id *id;

		/* device drivers never match interfaces */
		if (is_usb_device_driver(drv))
			return 0;

		intf = to_usb_interface(dev);
		usb_drv = to_usb_driver(drv);

		id = usb_match_id(intf, usb_drv->id_table);
		if (id)
			return 1;

		id = usb_match_dynamic_id(intf, usb_drv);
		if (id)
			return 1;
	}

	return 0;
}

static int usb_uevent(struct device *dev, char **envp, int num_envp,
		      char *buffer, int buffer_size)
{
	struct usb_device *usb_dev;
	int i = 0;
	int length = 0;

	if (!dev)
		return -ENODEV;

	/* driver is often null here; dev_dbg() would oops */
	pr_debug ("usb %s: uevent\n", dev->bus_id);

	if (is_usb_device(dev))
		usb_dev = to_usb_device(dev);
	else {
		struct usb_interface *intf = to_usb_interface(dev);
		usb_dev = interface_to_usbdev(intf);
	}

	if (usb_dev->devnum < 0) {
		pr_debug ("usb %s: already deleted?\n", dev->bus_id);
		return -ENODEV;
	}
	if (!usb_dev->bus) {
		pr_debug ("usb %s: bus removed?\n", dev->bus_id);
		return -ENODEV;
	}

	/* If this is available, userspace programs can directly read
	 * all the device descriptors we don't tell them about.  Or
	 * act as usermode drivers.
	 */
	if (add_uevent_var(envp, num_envp, &i,
			   buffer, buffer_size, &length,
			   "DEVICE=/proc/bus/usb/%03d/%03d",
			   usb_dev->bus->busnum, usb_dev->devnum))
		return -ENOMEM;

	/* per-device configurations are common */
	if (add_uevent_var(envp, num_envp, &i,
			   buffer, buffer_size, &length,
			   "PRODUCT=%x/%x/%x",
			   le16_to_cpu(usb_dev->descriptor.idVendor),
			   le16_to_cpu(usb_dev->descriptor.idProduct),
			   le16_to_cpu(usb_dev->descriptor.bcdDevice)))
		return -ENOMEM;

	/* class-based driver binding models */
	if (add_uevent_var(envp, num_envp, &i,
			   buffer, buffer_size, &length,
			   "TYPE=%d/%d/%d",
			   usb_dev->descriptor.bDeviceClass,
			   usb_dev->descriptor.bDeviceSubClass,
			   usb_dev->descriptor.bDeviceProtocol))
		return -ENOMEM;

	if (add_uevent_var(envp, num_envp, &i,
			   buffer, buffer_size, &length,
			   "BUSNUM=%03d",
			   usb_dev->bus->busnum))
		return -ENOMEM;

	if (add_uevent_var(envp, num_envp, &i,
			   buffer, buffer_size, &length,
			   "DEVNUM=%03d",
			   usb_dev->devnum))
		return -ENOMEM;

	envp[i] = NULL;
	return 0;
}


/**
 * usb_register_device_driver - register a USB device (not interface) driver
 * @new_udriver: USB operations for the device driver
 * @owner: module owner of this driver.
 *
 * Registers a USB device driver with the USB core.  The list of
 * unattached devices will be rescanned whenever a new driver is
 * added, allowing the new driver to attach to any recognized devices.
 * Returns a negative error code on failure and 0 on success.
 */
int usb_register_device_driver(struct usb_device_driver *new_udriver,
		struct module *owner)
{
	int retval = 0;

	if (usb_disabled())
		return -ENODEV;

	new_udriver->drvwrap.for_devices = 1;
	new_udriver->drvwrap.driver.name = (char *) new_udriver->name;
	new_udriver->drvwrap.driver.bus = &usb_bus_type;
	new_udriver->drvwrap.driver.probe = usb_probe_device;
	new_udriver->drvwrap.driver.remove = usb_unbind_device;
	new_udriver->drvwrap.driver.owner = owner;

	retval = driver_register(&new_udriver->drvwrap.driver);

	if (!retval) {
		pr_info("%s: registered new device driver %s\n",
			usbcore_name, new_udriver->name);
		usbfs_update_special();
	} else {
		printk(KERN_ERR "%s: error %d registering device "
			"	driver %s\n",
			usbcore_name, retval, new_udriver->name);
	}

	return retval;
}
EXPORT_SYMBOL_GPL(usb_register_device_driver);

/**
 * usb_deregister_device_driver - unregister a USB device (not interface) driver
 * @udriver: USB operations of the device driver to unregister
 * Context: must be able to sleep
 *
 * Unlinks the specified driver from the internal USB driver list.
 */
void usb_deregister_device_driver(struct usb_device_driver *udriver)
{
	pr_info("%s: deregistering device driver %s\n",
			usbcore_name, udriver->name);

	driver_unregister(&udriver->drvwrap.driver);
	usbfs_update_special();
}
EXPORT_SYMBOL_GPL(usb_deregister_device_driver);

/**
 * usb_register_driver - register a USB interface driver
 * @new_driver: USB operations for the interface driver
 * @owner: module owner of this driver.
 * @mod_name: module name string
 *
 * Registers a USB interface driver with the USB core.  The list of
 * unattached interfaces will be rescanned whenever a new driver is
 * added, allowing the new driver to attach to any recognized interfaces.
 * Returns a negative error code on failure and 0 on success.
 *
 * NOTE: if you want your driver to use the USB major number, you must call
 * usb_register_dev() to enable that functionality.  This function no longer
 * takes care of that.
 */
int usb_register_driver(struct usb_driver *new_driver, struct module *owner,
			const char *mod_name)
{
	int retval = 0;

	if (usb_disabled())
		return -ENODEV;

	new_driver->drvwrap.for_devices = 0;
	new_driver->drvwrap.driver.name = (char *) new_driver->name;
	new_driver->drvwrap.driver.bus = &usb_bus_type;
	new_driver->drvwrap.driver.probe = usb_probe_interface;
	new_driver->drvwrap.driver.remove = usb_unbind_interface;
	new_driver->drvwrap.driver.owner = owner;
	new_driver->drvwrap.driver.mod_name = mod_name;
	spin_lock_init(&new_driver->dynids.lock);
	INIT_LIST_HEAD(&new_driver->dynids.list);

	retval = driver_register(&new_driver->drvwrap.driver);

	if (!retval) {
		pr_info("%s: registered new interface driver %s\n",
			usbcore_name, new_driver->name);
		usbfs_update_special();
		usb_create_newid_file(new_driver);
	} else {
		printk(KERN_ERR "%s: error %d registering interface "
			"	driver %s\n",
			usbcore_name, retval, new_driver->name);
	}

	return retval;
}
EXPORT_SYMBOL_GPL_FUTURE(usb_register_driver);

/**
 * usb_deregister - unregister a USB interface driver
 * @driver: USB operations of the interface driver to unregister
 * Context: must be able to sleep
 *
 * Unlinks the specified driver from the internal USB driver list.
 *
 * NOTE: If you called usb_register_dev(), you still need to call
 * usb_deregister_dev() to clean up your driver's allocated minor numbers,
 * this * call will no longer do it for you.
 */
void usb_deregister(struct usb_driver *driver)
{
	pr_info("%s: deregistering interface driver %s\n",
			usbcore_name, driver->name);

	usb_remove_newid_file(driver);
	usb_free_dynids(driver);
	driver_unregister(&driver->drvwrap.driver);

	usbfs_update_special();
}
EXPORT_SYMBOL_GPL_FUTURE(usb_deregister);


/* Caller has locked udev's pm_mutex */
static int usb_suspend_device(struct usb_device *udev, pm_message_t msg)
{
	struct usb_device_driver	*udriver;
	int				status = 0;

	if (udev->state == USB_STATE_NOTATTACHED ||
			udev->state == USB_STATE_SUSPENDED)
		goto done;

	/* For devices that don't have a driver, we do a standard suspend. */
	if (udev->dev.driver == NULL) {
		udev->do_remote_wakeup = 0;
		status = usb_port_suspend(udev);
		goto done;
	}

	udriver = to_usb_device_driver(udev->dev.driver);
	status = udriver->suspend(udev, msg);

done:
	// dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status);
	if (status == 0)
		udev->dev.power.power_state.event = msg.event;
	return status;
}

/* Caller has locked udev's pm_mutex */
static int usb_resume_device(struct usb_device *udev)
{
	struct usb_device_driver	*udriver;
	int				status = 0;

	if (udev->state == USB_STATE_NOTATTACHED ||
			udev->state != USB_STATE_SUSPENDED)
		goto done;

	/* Can't resume it if it doesn't have a driver. */
	if (udev->dev.driver == NULL) {
		status = -ENOTCONN;
		goto done;
	}

	udriver = to_usb_device_driver(udev->dev.driver);
	status = udriver->resume(udev);

done:
	// dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status);
	if (status == 0) {
		udev->autoresume_disabled = 0;
		udev->dev.power.power_state.event = PM_EVENT_ON;
	}
	return status;
}

/* Caller has locked intf's usb_device's pm mutex */
static int usb_suspend_interface(struct usb_interface *intf, pm_message_t msg)
{
	struct usb_driver	*driver;
	int			status = 0;

	/* with no hardware, USB interfaces only use FREEZE and ON states */
	if (interface_to_usbdev(intf)->state == USB_STATE_NOTATTACHED ||
			!is_active(intf))
		goto done;

	if (intf->condition == USB_INTERFACE_UNBOUND)	/* This can't happen */
		goto done;
	driver = to_usb_driver(intf->dev.driver);

	if (driver->suspend && driver->resume) {
		status = driver->suspend(intf, msg);
		if (status == 0)
			mark_quiesced(intf);
		else if (!interface_to_usbdev(intf)->auto_pm)
			dev_err(&intf->dev, "%s error %d\n",
					"suspend", status);
	} else {
		// FIXME else if there's no suspend method, disconnect...
		// Not possible if auto_pm is set...
		dev_warn(&intf->dev, "no suspend for driver %s?\n",
				driver->name);
		mark_quiesced(intf);
	}

done:
	// dev_dbg(&intf->dev, "%s: status %d\n", __FUNCTION__, status);
	if (status == 0)
		intf->dev.power.power_state.event = msg.event;
	return status;
}

/* Caller has locked intf's usb_device's pm_mutex */
static int usb_resume_interface(struct usb_interface *intf)
{
	struct usb_driver	*driver;
	int			status = 0;

	if (interface_to_usbdev(intf)->state == USB_STATE_NOTATTACHED ||
			is_active(intf))
		goto done;

	/* Don't let autoresume interfere with unbinding */
	if (intf->condition == USB_INTERFACE_UNBINDING)
		goto done;

	/* Can't resume it if it doesn't have a driver. */
	if (intf->condition == USB_INTERFACE_UNBOUND) {
		status = -ENOTCONN;
		goto done;
	}
	driver = to_usb_driver(intf->dev.driver);

	if (driver->resume) {
		status = driver->resume(intf);
		if (status)
			dev_err(&intf->dev, "%s error %d\n",
					"resume", status);
		else
			mark_active(intf);
	} else {
		dev_warn(&intf->dev, "no resume for driver %s?\n",
				driver->name);
		mark_active(intf);
	}

done:
	// dev_dbg(&intf->dev, "%s: status %d\n", __FUNCTION__, status);
	if (status == 0)
		intf->dev.power.power_state.event = PM_EVENT_ON;
	return status;
}


/* Internal routine to check whether we may autosuspend a device. */
static int autosuspend_check(struct usb_device *udev)
{
	int			i;
	struct usb_interface	*intf;
	unsigned long		suspend_time;

	/* For autosuspend, fail fast if anything is in use or autosuspend
	 * is disabled.  Also fail if any interfaces require remote wakeup
	 * but it isn't available.
	 */
	udev->do_remote_wakeup = device_may_wakeup(&udev->dev);
	if (udev->pm_usage_cnt > 0)
		return -EBUSY;
	if (udev->autosuspend_delay < 0 || udev->autosuspend_disabled)
		return -EPERM;

	suspend_time = udev->last_busy + udev->autosuspend_delay;
	if (udev->actconfig) {
		for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
			intf = udev->actconfig->interface[i];
			if (!is_active(intf))
				continue;
			if (intf->pm_usage_cnt > 0)
				return -EBUSY;
			if (intf->needs_remote_wakeup &&
					!udev->do_remote_wakeup) {
				dev_dbg(&udev->dev, "remote wakeup needed "
						"for autosuspend\n");
				return -EOPNOTSUPP;
			}
		}
	}

	/* If everything is okay but the device hasn't been idle for long
	 * enough, queue a delayed autosuspend request.
	 */
	if (time_after(suspend_time, jiffies)) {
		if (!timer_pending(&udev->autosuspend.timer)) {

			/* The value of jiffies may change between the
			 * time_after() comparison above and the subtraction
			 * below.  That's okay; the system behaves sanely
			 * when a timer is registered for the present moment
			 * or for the past.
			 */
			queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend,
					suspend_time - jiffies);
			}
		return -EAGAIN;
	}
	return 0;
}


/**
 * usb_suspend_both - suspend a USB device and its interfaces
 * @udev: the usb_device to suspend
 * @msg: Power Management message describing this state transition
 *
 * This is the central routine for suspending USB devices.  It calls the
 * suspend methods for all the interface drivers in @udev and then calls
 * the suspend method for @udev itself.  If an error occurs at any stage,
 * all the interfaces which were suspended are resumed so that they remain
 * in the same state as the device.
 *
 * If an autosuspend is in progress (@udev->auto_pm is set), the routine
 * checks first to make sure that neither the device itself or any of its
 * active interfaces is in use (pm_usage_cnt is greater than 0).  If they
 * are, the autosuspend fails.
 *
 * If the suspend succeeds, the routine recursively queues an autosuspend
 * request for @udev's parent device, thereby propagating the change up
 * the device tree.  If all of the parent's children are now suspended,
 * the parent will autosuspend in turn.
 *
 * The suspend method calls are subject to mutual exclusion under control
 * of @udev's pm_mutex.  Many of these calls are also under the protection
 * of @udev's device lock (including all requests originating outside the
 * USB subsystem), but autosuspend requests generated by a child device or
 * interface driver may not be.  Usbcore will insure that the method calls
 * do not arrive during bind, unbind, or reset operations.  However, drivers
 * must be prepared to handle suspend calls arriving at unpredictable times.
 * The only way to block such calls is to do an autoresume (preventing
 * autosuspends) while holding @udev's device lock (preventing outside
 * suspends).
 *