idmouse.c

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/* 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  <[email protected]>
                      and Andreas  'ad'  Deresch <[email protected]>

  Derived from the USB Skeleton driver 1.1,
  Copyright (C) 2003 Greg Kroah-Hartman ([email protected])

  Additional information provided by Martin Reising
  <[email protected]>

*/

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/init.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 <[email protected]>"
#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\n",
        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.\n");
            idmouse_delete(dev);
            return -ENOMEM;
        }
    }

    if (!(dev->bulk_in_endpointAddr)) {
        dev_err(&interface->dev, "Unable to find bulk-in endpoint.\n");
        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, "Unble to allocate minor number.\n");
        usb_set_intfdata(interface, NULL);
        idmouse_delete(dev);
        return result;
    }

    /* be noisy */
    dev_info(&interface->dev,"%s now attached\n",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\n");
}

module_usb_driver(idmouse_driver);

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