/* Siemens ID Mouse driver v0.6

  
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
    published by the Free Software Foundation; either version 2 of
    the License, or (at your option) any later version.
  
    Copyright (C) 2004-5 by Florian 'Floe' Echtler  <echtler@fs.tum.de>
                        and Andreas  'ad'  Deresch <aderesch@fs.tum.de>
  
    Derived from the USB Skeleton driver 1.1,
    Copyright (C) 2003 Greg Kroah-Hartman (greg@kroah.com)

    Additional information provided by Martin Reising
    <Martin.Reising@natural-computing.de>

  */

  #include <linux/kernel.h>
  #include <linux/errno.h>
  #include <linux/delay.h>

  #include <linux/slab.h>
  #include <linux/module.h>

  #include <linux/completion.h>

  #include <linux/mutex.h>

  #include <asm/uaccess.h>
  #include <linux/usb.h>

  /* image constants */

  #define WIDTH 225

  #define HEIGHT 289
  #define HEADER "P5 225 289 255 "

  #define IMGSIZE ((WIDTH * HEIGHT) + sizeof(HEADER)-1)

  /* version information */
  #define DRIVER_VERSION "0.6"

  #define DRIVER_SHORT   "idmouse"
  #define DRIVER_AUTHOR  "Florian 'Floe' Echtler <echtler@fs.tum.de>"
  #define DRIVER_DESC    "Siemens ID Mouse FingerTIP Sensor Driver"

  /* minor number for misc USB devices */

  #define USB_IDMOUSE_MINOR_BASE 132

  /* vendor and device IDs */
  #define ID_SIEMENS 0x0681
  #define ID_IDMOUSE 0x0005
  #define ID_CHERRY  0x0010
  
  /* device ID table */

  static const struct usb_device_id idmouse_table[] = {

  	{USB_DEVICE(ID_SIEMENS, ID_IDMOUSE)}, /* Siemens ID Mouse (Professional) */
  	{USB_DEVICE(ID_SIEMENS, ID_CHERRY )}, /* Cherry FingerTIP ID Board       */
  	{}                                    /* terminating null entry          */

  };

  /* sensor commands */
  #define FTIP_RESET   0x20
  #define FTIP_ACQUIRE 0x21
  #define FTIP_RELEASE 0x22
  #define FTIP_BLINK   0x23  /* LSB of value = blink pulse width */
  #define FTIP_SCROLL  0x24
  
  #define ftip_command(dev, command, value, index) \
  	usb_control_msg (dev->udev, usb_sndctrlpipe (dev->udev, 0), command, \
  	USB_TYPE_VENDOR | USB_RECIP_ENDPOINT | USB_DIR_OUT, value, index, NULL, 0, 1000)

  MODULE_DEVICE_TABLE(usb, idmouse_table);

  static DEFINE_MUTEX(open_disc_mutex);

  
  /* structure to hold all of our device specific stuff */
  struct usb_idmouse {
  
  	struct usb_device *udev; /* save off the usb device pointer */
  	struct usb_interface *interface; /* the interface for this device */
  
  	unsigned char *bulk_in_buffer; /* the buffer to receive data */

  	size_t bulk_in_size; /* the maximum bulk packet size */
  	size_t orig_bi_size; /* same as above, but reported by the device */

  	__u8 bulk_in_endpointAddr; /* the address of the bulk in endpoint */
  
  	int open; /* if the port is open or not */
  	int present; /* if the device is not disconnected */

  	struct mutex lock; /* locks this structure */

  
  };
  
  /* local function prototypes */
  static ssize_t idmouse_read(struct file *file, char __user *buffer,
  				size_t count, loff_t * ppos);
  
  static int idmouse_open(struct inode *inode, struct file *file);
  static int idmouse_release(struct inode *inode, struct file *file);
  
  static int idmouse_probe(struct usb_interface *interface,
  				const struct usb_device_id *id);
  
  static void idmouse_disconnect(struct usb_interface *interface);

  static int idmouse_suspend(struct usb_interface *intf, pm_message_t message);
  static int idmouse_resume(struct usb_interface *intf);

  
  /* file operation pointers */

  static const struct file_operations idmouse_fops = {

  	.owner = THIS_MODULE,
  	.read = idmouse_read,
  	.open = idmouse_open,
  	.release = idmouse_release,

  	.llseek = default_llseek,

  };

  /* class driver information */

  static struct usb_class_driver idmouse_class = {

  	.name = "idmouse%d",

  	.fops = &idmouse_fops,

  	.minor_base = USB_IDMOUSE_MINOR_BASE,
  };
  
  /* usb specific object needed to register this driver with the usb subsystem */
  static struct usb_driver idmouse_driver = {

  	.name = DRIVER_SHORT,
  	.probe = idmouse_probe,
  	.disconnect = idmouse_disconnect,

  	.suspend = idmouse_suspend,
  	.resume = idmouse_resume,
  	.reset_resume = idmouse_resume,

  	.id_table = idmouse_table,

  	.supports_autosuspend = 1,

  };

  static int idmouse_create_image(struct usb_idmouse *dev)
  {

  	int bytes_read;
  	int bulk_read;
  	int result;

  	memcpy(dev->bulk_in_buffer, HEADER, sizeof(HEADER)-1);

  	bytes_read = sizeof(HEADER)-1;

  	/* reset the device and set a fast blink rate */
  	result = ftip_command(dev, FTIP_RELEASE, 0, 0);

  	if (result < 0)

  		goto reset;
  	result = ftip_command(dev, FTIP_BLINK,   1, 0);

  	if (result < 0)

  		goto reset;

  	/* initialize the sensor - sending this command twice */
  	/* significantly reduces the rate of failed reads     */
  	result = ftip_command(dev, FTIP_ACQUIRE, 0, 0);

  	if (result < 0)

  		goto reset;
  	result = ftip_command(dev, FTIP_ACQUIRE, 0, 0);

  	if (result < 0)

  		goto reset;
  
  	/* start the readout - sending this command twice */
  	/* presumably enables the high dynamic range mode */
  	result = ftip_command(dev, FTIP_RESET,   0, 0);

  	if (result < 0)

  		goto reset;
  	result = ftip_command(dev, FTIP_RESET,   0, 0);
  	if (result < 0)
  		goto reset;

  
  	/* loop over a blocking bulk read to get data from the device */
  	while (bytes_read < IMGSIZE) {
  		result = usb_bulk_msg (dev->udev,
  				usb_rcvbulkpipe (dev->udev, dev->bulk_in_endpointAddr),
  				dev->bulk_in_buffer + bytes_read,
  				dev->bulk_in_size, &bulk_read, 5000);

  		if (result < 0) {
  			/* Maybe this error was caused by the increased packet size? */
  			/* Reset to the original value and tell userspace to retry.  */
  			if (dev->bulk_in_size != dev->orig_bi_size) {
  				dev->bulk_in_size = dev->orig_bi_size;
  				result = -EAGAIN;
  			}
  			break;
  		}
  		if (signal_pending(current)) {
  			result = -EINTR;
  			break;
  		}

  		bytes_read += bulk_read;
  	}
  
  	/* reset the device */

  reset:
  	ftip_command(dev, FTIP_RELEASE, 0, 0);
  
  	/* check for valid image */
  	/* right border should be black (0x00) */
  	for (bytes_read = sizeof(HEADER)-1 + WIDTH-1; bytes_read < IMGSIZE; bytes_read += WIDTH)
  		if (dev->bulk_in_buffer[bytes_read] != 0x00)
  			return -EAGAIN;

  	/* lower border should be white (0xFF) */
  	for (bytes_read = IMGSIZE-WIDTH; bytes_read < IMGSIZE-1; bytes_read++)
  		if (dev->bulk_in_buffer[bytes_read] != 0xFF)
  			return -EAGAIN;
  
  	/* should be IMGSIZE == 65040 */

  	dev_dbg(&dev->interface->dev, "read %d bytes fingerprint data
  ",
  		bytes_read);

  	return result;

  }

  /* PM operations are nops as this driver does IO only during open() */
  static int idmouse_suspend(struct usb_interface *intf, pm_message_t message)
  {
  	return 0;
  }
  
  static int idmouse_resume(struct usb_interface *intf)
  {
  	return 0;
  }

  static inline void idmouse_delete(struct usb_idmouse *dev)
  {
  	kfree(dev->bulk_in_buffer);
  	kfree(dev);
  }
  
  static int idmouse_open(struct inode *inode, struct file *file)
  {

  	struct usb_idmouse *dev;

  	struct usb_interface *interface;

  	int result;

  	/* get the interface from minor number and driver information */
  	interface = usb_find_interface (&idmouse_driver, iminor (inode));

  	if (!interface)

  		return -ENODEV;

  	mutex_lock(&open_disc_mutex);

  	/* get the device information block from the interface */
  	dev = usb_get_intfdata(interface);

  	if (!dev) {
  		mutex_unlock(&open_disc_mutex);

  		return -ENODEV;

  	}

  
  	/* lock this device */

  	mutex_lock(&dev->lock);
  	mutex_unlock(&open_disc_mutex);

  
  	/* check if already open */
  	if (dev->open) {
  
  		/* already open, so fail */
  		result = -EBUSY;
  
  	} else {
  
  		/* create a new image and check for success */

  		result = usb_autopm_get_interface(interface);
  		if (result)
  			goto error;

  		result = idmouse_create_image (dev);
  		if (result)
  			goto error;

  		usb_autopm_put_interface(interface);

  
  		/* increment our usage count for the driver */
  		++dev->open;
  
  		/* save our object in the file's private structure */
  		file->private_data = dev;
  
  	} 
  
  error:
  
  	/* unlock this device */

  	mutex_unlock(&dev->lock);

  	return result;
  }
  
  static int idmouse_release(struct inode *inode, struct file *file)
  {
  	struct usb_idmouse *dev;

  	dev = file->private_data;

  	if (dev == NULL)

  		return -ENODEV;

  	mutex_lock(&open_disc_mutex);

  	/* lock our device */

  	mutex_lock(&dev->lock);

  
  	/* are we really open? */
  	if (dev->open <= 0) {

  		mutex_unlock(&dev->lock);
  		mutex_unlock(&open_disc_mutex);

  		return -ENODEV;
  	}
  
  	--dev->open;
  
  	if (!dev->present) {
  		/* the device was unplugged before the file was released */

  		mutex_unlock(&dev->lock);
  		mutex_unlock(&open_disc_mutex);

  		idmouse_delete(dev);

  	} else {

  		mutex_unlock(&dev->lock);
  		mutex_unlock(&open_disc_mutex);

  	}

  	return 0;
  }
  
  static ssize_t idmouse_read(struct file *file, char __user *buffer, size_t count,
  				loff_t * ppos)
  {

  	struct usb_idmouse *dev = file->private_data;

  	int result;

  	/* lock this object */

  	mutex_lock(&dev->lock);

  	/* verify that the device wasn't unplugged */

  	if (!dev->present) {

  		mutex_unlock(&dev->lock);

  		return -ENODEV;
  	}

  	result = simple_read_from_buffer(buffer, count, ppos,
  					dev->bulk_in_buffer, IMGSIZE);

  	/* unlock the device */

  	mutex_unlock(&dev->lock);

  	return result;
  }
  
  static int idmouse_probe(struct usb_interface *interface,
  				const struct usb_device_id *id)
  {
  	struct usb_device *udev = interface_to_usbdev(interface);

  	struct usb_idmouse *dev;

  	struct usb_host_interface *iface_desc;
  	struct usb_endpoint_descriptor *endpoint;

  	int result;
  
  	/* check if we have gotten the data or the hid interface */
  	iface_desc = &interface->altsetting[0];
  	if (iface_desc->desc.bInterfaceClass != 0x0A)
  		return -ENODEV;
  
  	/* allocate memory for our device state and initialize it */

  	dev = kzalloc(sizeof(*dev), GFP_KERNEL);

  	if (dev == NULL)
  		return -ENOMEM;

  	mutex_init(&dev->lock);

  	dev->udev = udev;
  	dev->interface = interface;
  
  	/* set up the endpoint information - use only the first bulk-in endpoint */
  	endpoint = &iface_desc->endpoint[0].desc;

  	if (!dev->bulk_in_endpointAddr && usb_endpoint_is_bulk_in(endpoint)) {

  		/* we found a bulk in endpoint */

  		dev->orig_bi_size = usb_endpoint_maxp(endpoint);

  		dev->bulk_in_size = 0x200; /* works _much_ faster */

  		dev->bulk_in_endpointAddr = endpoint->bEndpointAddress;
  		dev->bulk_in_buffer =

  			kmalloc(IMGSIZE + dev->bulk_in_size, GFP_KERNEL);

  
  		if (!dev->bulk_in_buffer) {

  			dev_err(&interface->dev, "Unable to allocate input buffer.
  ");

  			idmouse_delete(dev);
  			return -ENOMEM;
  		}
  	}
  
  	if (!(dev->bulk_in_endpointAddr)) {

  		dev_err(&interface->dev, "Unable to find bulk-in endpoint.
  ");

  		idmouse_delete(dev);
  		return -ENODEV;
  	}
  	/* allow device read, write and ioctl */
  	dev->present = 1;
  
  	/* we can register the device now, as it is ready */
  	usb_set_intfdata(interface, dev);
  	result = usb_register_dev(interface, &idmouse_class);
  	if (result) {
  		/* something prevented us from registering this device */

  		dev_err(&interface->dev, "Unable to allocate minor number.
  ");

  		usb_set_intfdata(interface, NULL);
  		idmouse_delete(dev);
  		return result;
  	}
  
  	/* be noisy */
  	dev_info(&interface->dev,"%s now attached
  ",DRIVER_DESC);
  
  	return 0;
  }
  
  static void idmouse_disconnect(struct usb_interface *interface)
  {
  	struct usb_idmouse *dev;

  	/* get device structure */
  	dev = usb_get_intfdata(interface);

  	/* give back our minor */
  	usb_deregister_dev(interface, &idmouse_class);

  	mutex_lock(&open_disc_mutex);
  	usb_set_intfdata(interface, NULL);
  	/* lock the device */
  	mutex_lock(&dev->lock);
  	mutex_unlock(&open_disc_mutex);

  	/* prevent device read, write and ioctl */
  	dev->present = 0;

  	/* if the device is opened, idmouse_release will clean this up */

  	if (!dev->open) {

  		mutex_unlock(&dev->lock);

  		idmouse_delete(dev);

  	} else {
  		/* unlock */

  		mutex_unlock(&dev->lock);

  	}

  	dev_info(&interface->dev, "disconnected
  ");

  }

  module_usb_driver(idmouse_driver);

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