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cm4040_cs.c

/*
 * A driver for the Omnikey PCMCIA smartcard reader CardMan 4040
 *
 * (c) 2000-2004 Omnikey AG (http://www.omnikey.com/)
 *
 * (C) 2005-2006 Harald Welte <laforge@gnumonks.org>
 *    - add support for poll()
 *    - driver cleanup
 *    - add waitqueues
 *    - adhere to linux kernel coding style and policies
 *    - support 2.6.13 "new style" pcmcia interface
 *    - add class interface for udev device creation
 *
 * The device basically is a USB CCID compliant device that has been
 * attached to an I/O-Mapped FIFO.
 *
 * All rights reserved, Dual BSD/GPL Licensed.
 */

/* #define PCMCIA_DEBUG 6 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/delay.h>
#include <linux/poll.h>
#include <linux/wait.h>
#include <asm/uaccess.h>
#include <asm/io.h>

#include <pcmcia/cs_types.h>
#include <pcmcia/cs.h>
#include <pcmcia/cistpl.h>
#include <pcmcia/cisreg.h>
#include <pcmcia/ciscode.h>
#include <pcmcia/ds.h>

#include "cm4040_cs.h"


#ifdef PCMCIA_DEBUG
#define reader_to_dev(x)      (&handle_to_dev(x->p_dev))
static int pc_debug = PCMCIA_DEBUG;
module_param(pc_debug, int, 0600);
#define DEBUGP(n, rdr, x, args...) do {                     \
      if (pc_debug >= (n))                                  \
            dev_printk(KERN_DEBUG, reader_to_dev(rdr), "%s:" x,   \
                     __FUNCTION__ , ##args);                \
      } while (0)
#else
#define DEBUGP(n, rdr, x, args...)
#endif

static char *version =
"OMNIKEY CardMan 4040 v1.1.0gm5 - All bugs added by Harald Welte";

#define     CCID_DRIVER_BULK_DEFAULT_TIMEOUT    (150*HZ)
#define     CCID_DRIVER_ASYNC_POWERUP_TIMEOUT   (35*HZ)
#define     CCID_DRIVER_MINIMUM_TIMEOUT         (3*HZ)
#define READ_WRITE_BUFFER_SIZE 512
#define POLL_LOOP_COUNT                   1000

/* how often to poll for fifo status change */
#define POLL_PERIOD                       msecs_to_jiffies(10)

static void reader_release(struct pcmcia_device *link);

static int major;
static struct class *cmx_class;

#define           BS_READABLE 0x01
#define           BS_WRITABLE 0x02

struct reader_dev {
      struct pcmcia_device    *p_dev;
      dev_node_t        node;
      wait_queue_head_t devq;
      wait_queue_head_t poll_wait;
      wait_queue_head_t read_wait;
      wait_queue_head_t write_wait;
      unsigned long           buffer_status;
      unsigned long           timeout;
      unsigned char           s_buf[READ_WRITE_BUFFER_SIZE];
      unsigned char           r_buf[READ_WRITE_BUFFER_SIZE];
      struct timer_list       poll_timer;
};

static struct pcmcia_device *dev_table[CM_MAX_DEV];

#ifndef PCMCIA_DEBUG
#define     xoutb outb
#define     xinb  inb
#else
static inline void xoutb(unsigned char val, unsigned short port)
{
      if (pc_debug >= 7)
            printk(KERN_DEBUG "outb(val=%.2x,port=%.4x)\n", val, port);
      outb(val, port);
}

static inline unsigned char xinb(unsigned short port)
{
      unsigned char val;

      val = inb(port);
      if (pc_debug >= 7)
            printk(KERN_DEBUG "%.2x=inb(%.4x)\n", val, port);
      return val;
}
#endif

/* poll the device fifo status register.  not to be confused with
 * the poll syscall. */
static void cm4040_do_poll(unsigned long dummy)
{
      struct reader_dev *dev = (struct reader_dev *) dummy;
      unsigned int obs = xinb(dev->p_dev->io.BasePort1
                        + REG_OFFSET_BUFFER_STATUS);

      if ((obs & BSR_BULK_IN_FULL)) {
            set_bit(BS_READABLE, &dev->buffer_status);
            DEBUGP(4, dev, "waking up read_wait\n");
            wake_up_interruptible(&dev->read_wait);
      } else
            clear_bit(BS_READABLE, &dev->buffer_status);

      if (!(obs & BSR_BULK_OUT_FULL)) {
            set_bit(BS_WRITABLE, &dev->buffer_status);
            DEBUGP(4, dev, "waking up write_wait\n");
            wake_up_interruptible(&dev->write_wait);
      } else
            clear_bit(BS_WRITABLE, &dev->buffer_status);

      if (dev->buffer_status)
            wake_up_interruptible(&dev->poll_wait);

      mod_timer(&dev->poll_timer, jiffies + POLL_PERIOD);
}

static void cm4040_stop_poll(struct reader_dev *dev)
{
      del_timer_sync(&dev->poll_timer);
}

static int wait_for_bulk_out_ready(struct reader_dev *dev)
{
      int i, rc;
      int iobase = dev->p_dev->io.BasePort1;

      for (i = 0; i < POLL_LOOP_COUNT; i++) {
            if ((xinb(iobase + REG_OFFSET_BUFFER_STATUS)
                & BSR_BULK_OUT_FULL) == 0) {
                  DEBUGP(4, dev, "BulkOut empty (i=%d)\n", i);
                  return 1;
            }
      }

      DEBUGP(4, dev, "wait_event_interruptible_timeout(timeout=%ld\n",
            dev->timeout);
      rc = wait_event_interruptible_timeout(dev->write_wait,
                                    test_and_clear_bit(BS_WRITABLE,
                                           &dev->buffer_status),
                                    dev->timeout);

      if (rc > 0)
            DEBUGP(4, dev, "woke up: BulkOut empty\n");
      else if (rc == 0)
            DEBUGP(4, dev, "woke up: BulkOut full, returning 0 :(\n");
      else if (rc < 0)
            DEBUGP(4, dev, "woke up: signal arrived\n");

      return rc;
}

/* Write to Sync Control Register */
static int write_sync_reg(unsigned char val, struct reader_dev *dev)
{
      int iobase = dev->p_dev->io.BasePort1;
      int rc;

      rc = wait_for_bulk_out_ready(dev);
      if (rc <= 0)
            return rc;

      xoutb(val, iobase + REG_OFFSET_SYNC_CONTROL);
      rc = wait_for_bulk_out_ready(dev);
      if (rc <= 0)
            return rc;

      return 1;
}

static int wait_for_bulk_in_ready(struct reader_dev *dev)
{
      int i, rc;
      int iobase = dev->p_dev->io.BasePort1;

      for (i = 0; i < POLL_LOOP_COUNT; i++) {
            if ((xinb(iobase + REG_OFFSET_BUFFER_STATUS)
                & BSR_BULK_IN_FULL) == BSR_BULK_IN_FULL) {
                  DEBUGP(3, dev, "BulkIn full (i=%d)\n", i);
                  return 1;
            }
      }

      DEBUGP(4, dev, "wait_event_interruptible_timeout(timeout=%ld\n",
            dev->timeout);
      rc = wait_event_interruptible_timeout(dev->read_wait,
                                    test_and_clear_bit(BS_READABLE,
                                          &dev->buffer_status),
                                    dev->timeout);
      if (rc > 0)
            DEBUGP(4, dev, "woke up: BulkIn full\n");
      else if (rc == 0)
            DEBUGP(4, dev, "woke up: BulkIn not full, returning 0 :(\n");
      else if (rc < 0)
            DEBUGP(4, dev, "woke up: signal arrived\n");

      return rc;
}

static ssize_t cm4040_read(struct file *filp, char __user *buf,
                  size_t count, loff_t *ppos)
{
      struct reader_dev *dev = filp->private_data;
      int iobase = dev->p_dev->io.BasePort1;
      size_t bytes_to_read;
      unsigned long i;
      size_t min_bytes_to_read;
      int rc;
      unsigned char uc;

      DEBUGP(2, dev, "-> cm4040_read(%s,%d)\n", current->comm, current->pid);

      if (count == 0)
            return 0;

      if (count < 10)
            return -EFAULT;

      if (filp->f_flags & O_NONBLOCK) {
            DEBUGP(4, dev, "filep->f_flags O_NONBLOCK set\n");
            DEBUGP(2, dev, "<- cm4040_read (failure)\n");
            return -EAGAIN;
      }

      if (!pcmcia_dev_present(dev->p_dev))
            return -ENODEV;

      for (i = 0; i < 5; i++) {
            rc = wait_for_bulk_in_ready(dev);
            if (rc <= 0) {
                  DEBUGP(5, dev, "wait_for_bulk_in_ready rc=%.2x\n", rc);
                  DEBUGP(2, dev, "<- cm4040_read (failed)\n");
                  if (rc == -ERESTARTSYS)
                        return rc;
                  return -EIO;
            }
            dev->r_buf[i] = xinb(iobase + REG_OFFSET_BULK_IN);
#ifdef PCMCIA_DEBUG
            if (pc_debug >= 6)
                  printk(KERN_DEBUG "%lu:%2x ", i, dev->r_buf[i]);
      }
      printk("\n");
#else
      }
#endif

      bytes_to_read = 5 + le32_to_cpu(*(__le32 *)&dev->r_buf[1]);

      DEBUGP(6, dev, "BytesToRead=%lu\n", bytes_to_read);

      min_bytes_to_read = min(count, bytes_to_read + 5);
      min_bytes_to_read = min_t(size_t, min_bytes_to_read, READ_WRITE_BUFFER_SIZE);

      DEBUGP(6, dev, "Min=%lu\n", min_bytes_to_read);

      for (i = 0; i < (min_bytes_to_read-5); i++) {
            rc = wait_for_bulk_in_ready(dev);
            if (rc <= 0) {
                  DEBUGP(5, dev, "wait_for_bulk_in_ready rc=%.2x\n", rc);
                  DEBUGP(2, dev, "<- cm4040_read (failed)\n");
                  if (rc == -ERESTARTSYS)
                        return rc;
                  return -EIO;
            }
            dev->r_buf[i+5] = xinb(iobase + REG_OFFSET_BULK_IN);
#ifdef PCMCIA_DEBUG
            if (pc_debug >= 6)
                  printk(KERN_DEBUG "%lu:%2x ", i, dev->r_buf[i]);
      }
      printk("\n");
#else
      }
#endif

      *ppos = min_bytes_to_read;
      if (copy_to_user(buf, dev->r_buf, min_bytes_to_read))
            return -EFAULT;

      rc = wait_for_bulk_in_ready(dev);
      if (rc <= 0) {
            DEBUGP(5, dev, "wait_for_bulk_in_ready rc=%.2x\n", rc);
            DEBUGP(2, dev, "<- cm4040_read (failed)\n");
            if (rc == -ERESTARTSYS)
                  return rc;
            return -EIO;
      }

      rc = write_sync_reg(SCR_READER_TO_HOST_DONE, dev);
      if (rc <= 0) {
            DEBUGP(5, dev, "write_sync_reg c=%.2x\n", rc);
            DEBUGP(2, dev, "<- cm4040_read (failed)\n");
            if (rc == -ERESTARTSYS)
                  return rc;
            else
                  return -EIO;
      }

      uc = xinb(iobase + REG_OFFSET_BULK_IN);

      DEBUGP(2, dev, "<- cm4040_read (successfully)\n");
      return min_bytes_to_read;
}

static ssize_t cm4040_write(struct file *filp, const char __user *buf,
                   size_t count, loff_t *ppos)
{
      struct reader_dev *dev = filp->private_data;
      int iobase = dev->p_dev->io.BasePort1;
      ssize_t rc;
      int i;
      unsigned int bytes_to_write;

      DEBUGP(2, dev, "-> cm4040_write(%s,%d)\n", current->comm, current->pid);

      if (count == 0) {
            DEBUGP(2, dev, "<- cm4040_write empty read (successfully)\n");
            return 0;
      }

      if ((count < 5) || (count > READ_WRITE_BUFFER_SIZE)) {
            DEBUGP(2, dev, "<- cm4040_write buffersize=%Zd < 5\n", count);
            return -EIO;
      }

      if (filp->f_flags & O_NONBLOCK) {
            DEBUGP(4, dev, "filep->f_flags O_NONBLOCK set\n");
            DEBUGP(4, dev, "<- cm4040_write (failure)\n");
            return -EAGAIN;
      }

      if (!pcmcia_dev_present(dev->p_dev))
            return -ENODEV;

      bytes_to_write = count;
      if (copy_from_user(dev->s_buf, buf, bytes_to_write))
            return -EFAULT;

      switch (dev->s_buf[0]) {
            case CMD_PC_TO_RDR_XFRBLOCK:
            case CMD_PC_TO_RDR_SECURE:
            case CMD_PC_TO_RDR_TEST_SECURE:
            case CMD_PC_TO_RDR_OK_SECURE:
                  dev->timeout = CCID_DRIVER_BULK_DEFAULT_TIMEOUT;
                  break;

            case CMD_PC_TO_RDR_ICCPOWERON:
                  dev->timeout = CCID_DRIVER_ASYNC_POWERUP_TIMEOUT;
                  break;

            case CMD_PC_TO_RDR_GETSLOTSTATUS:
            case CMD_PC_TO_RDR_ICCPOWEROFF:
            case CMD_PC_TO_RDR_GETPARAMETERS:
            case CMD_PC_TO_RDR_RESETPARAMETERS:
            case CMD_PC_TO_RDR_SETPARAMETERS:
            case CMD_PC_TO_RDR_ESCAPE:
            case CMD_PC_TO_RDR_ICCCLOCK:
            default:
                  dev->timeout = CCID_DRIVER_MINIMUM_TIMEOUT;
                  break;
      }

      rc = write_sync_reg(SCR_HOST_TO_READER_START, dev);
      if (rc <= 0) {
            DEBUGP(5, dev, "write_sync_reg c=%.2Zx\n", rc);
            DEBUGP(2, dev, "<- cm4040_write (failed)\n");
            if (rc == -ERESTARTSYS)
                  return rc;
            else
                  return -EIO;
      }

      DEBUGP(4, dev, "start \n");

      for (i = 0; i < bytes_to_write; i++) {
            rc = wait_for_bulk_out_ready(dev);
            if (rc <= 0) {
                  DEBUGP(5, dev, "wait_for_bulk_out_ready rc=%.2Zx\n",
                         rc);
                  DEBUGP(2, dev, "<- cm4040_write (failed)\n");
                  if (rc == -ERESTARTSYS)
                        return rc;
                  else
                        return -EIO;
            }

            xoutb(dev->s_buf[i],iobase + REG_OFFSET_BULK_OUT);
      }
      DEBUGP(4, dev, "end\n");

      rc = write_sync_reg(SCR_HOST_TO_READER_DONE, dev);

      if (rc <= 0) {
            DEBUGP(5, dev, "write_sync_reg c=%.2Zx\n", rc);
            DEBUGP(2, dev, "<- cm4040_write (failed)\n");
            if (rc == -ERESTARTSYS)
                  return rc;
            else
                  return -EIO;
      }

      DEBUGP(2, dev, "<- cm4040_write (successfully)\n");
      return count;
}

static unsigned int cm4040_poll(struct file *filp, poll_table *wait)
{
      struct reader_dev *dev = filp->private_data;
      unsigned int mask = 0;

      poll_wait(filp, &dev->poll_wait, wait);

      if (test_and_clear_bit(BS_READABLE, &dev->buffer_status))
            mask |= POLLIN | POLLRDNORM;
      if (test_and_clear_bit(BS_WRITABLE, &dev->buffer_status))
            mask |= POLLOUT | POLLWRNORM;

      DEBUGP(2, dev, "<- cm4040_poll(%u)\n", mask);

      return mask;
}

static int cm4040_open(struct inode *inode, struct file *filp)
{
      struct reader_dev *dev;
      struct pcmcia_device *link;
      int minor = iminor(inode);

      if (minor >= CM_MAX_DEV)
            return -ENODEV;

      link = dev_table[minor];
      if (link == NULL || !pcmcia_dev_present(link))
            return -ENODEV;

      if (link->open)
            return -EBUSY;

      dev = link->priv;
      filp->private_data = dev;

      if (filp->f_flags & O_NONBLOCK) {
            DEBUGP(4, dev, "filep->f_flags O_NONBLOCK set\n");
            return -EAGAIN;
      }

      link->open = 1;

      dev->poll_timer.data = (unsigned long) dev;
      mod_timer(&dev->poll_timer, jiffies + POLL_PERIOD);

      DEBUGP(2, dev, "<- cm4040_open (successfully)\n");
      return nonseekable_open(inode, filp);
}

static int cm4040_close(struct inode *inode, struct file *filp)
{
      struct reader_dev *dev = filp->private_data;
      struct pcmcia_device *link;
      int minor = iminor(inode);

      DEBUGP(2, dev, "-> cm4040_close(maj/min=%d.%d)\n", imajor(inode),
            iminor(inode));

      if (minor >= CM_MAX_DEV)
            return -ENODEV;

      link = dev_table[minor];
      if (link == NULL)
            return -ENODEV;

      cm4040_stop_poll(dev);

      link->open = 0;
      wake_up(&dev->devq);

      DEBUGP(2, dev, "<- cm4040_close\n");
      return 0;
}

static void cm4040_reader_release(struct pcmcia_device *link)
{
      struct reader_dev *dev = link->priv;

      DEBUGP(3, dev, "-> cm4040_reader_release\n");
      while (link->open) {
            DEBUGP(3, dev, KERN_INFO MODULE_NAME ": delaying release "
                   "until process has terminated\n");
            wait_event(dev->devq, (link->open == 0));
      }
      DEBUGP(3, dev, "<- cm4040_reader_release\n");
      return;
}

static int reader_config(struct pcmcia_device *link, int devno)
{
      struct reader_dev *dev;
      tuple_t tuple;
      cisparse_t parse;
      u_char buf[64];
      int fail_fn, fail_rc;
      int rc;

      tuple.Attributes = 0;
      tuple.TupleData = buf;
      tuple.TupleDataMax = sizeof(buf);
      tuple.TupleOffset = 0;

      link->io.BasePort2 = 0;
      link->io.NumPorts2 = 0;
      link->io.Attributes2 = 0;
      tuple.DesiredTuple = CISTPL_CFTABLE_ENTRY;
      for (rc = pcmcia_get_first_tuple(link, &tuple);
           rc == CS_SUCCESS;
           rc = pcmcia_get_next_tuple(link, &tuple)) {
            rc = pcmcia_get_tuple_data(link, &tuple);
            if (rc != CS_SUCCESS)
                  continue;
            rc = pcmcia_parse_tuple(link, &tuple, &parse);
            if (rc != CS_SUCCESS)
                  continue;

            link->conf.ConfigIndex = parse.cftable_entry.index;

            if (!parse.cftable_entry.io.nwin)
                  continue;

            link->io.BasePort1 = parse.cftable_entry.io.win[0].base;
            link->io.NumPorts1 = parse.cftable_entry.io.win[0].len;
            link->io.Attributes1 = IO_DATA_PATH_WIDTH_AUTO;
            if (!(parse.cftable_entry.io.flags & CISTPL_IO_8BIT))
                  link->io.Attributes1 = IO_DATA_PATH_WIDTH_16;
            if (!(parse.cftable_entry.io.flags & CISTPL_IO_16BIT))
                  link->io.Attributes1 = IO_DATA_PATH_WIDTH_8;
            link->io.IOAddrLines = parse.cftable_entry.io.flags
                                    & CISTPL_IO_LINES_MASK;
            rc = pcmcia_request_io(link, &link->io);

            dev_printk(KERN_INFO, &handle_to_dev(link), "foo");
            if (rc == CS_SUCCESS)
                  break;
            else
                  dev_printk(KERN_INFO, &handle_to_dev(link),
                           "pcmcia_request_io failed 0x%x\n", rc);
      }
      if (rc != CS_SUCCESS)
            goto cs_release;

      link->conf.IntType = 00000002;

      if ((fail_rc = pcmcia_request_configuration(link,&link->conf))
                                                !=CS_SUCCESS) {
            fail_fn = RequestConfiguration;
            dev_printk(KERN_INFO, &handle_to_dev(link),
                     "pcmcia_request_configuration failed 0x%x\n",
                     fail_rc);
            goto cs_release;
      }

      dev = link->priv;
      sprintf(dev->node.dev_name, DEVICE_NAME "%d", devno);
      dev->node.major = major;
      dev->node.minor = devno;
      dev->node.next = &dev->node;

      DEBUGP(2, dev, "device " DEVICE_NAME "%d at 0x%.4x-0x%.4x\n", devno,
            link->io.BasePort1, link->io.BasePort1+link->io.NumPorts1);
      DEBUGP(2, dev, "<- reader_config (succ)\n");

      return 0;

cs_release:
      reader_release(link);
      return -ENODEV;
}

static void reader_release(struct pcmcia_device *link)
{
      cm4040_reader_release(link);
      pcmcia_disable_device(link);
}

static int reader_probe(struct pcmcia_device *link)
{
      struct reader_dev *dev;
      int i, ret;

      for (i = 0; i < CM_MAX_DEV; i++) {
            if (dev_table[i] == NULL)
                  break;
      }

      if (i == CM_MAX_DEV)
            return -ENODEV;

      dev = kzalloc(sizeof(struct reader_dev), GFP_KERNEL);
      if (dev == NULL)
            return -ENOMEM;

      dev->timeout = CCID_DRIVER_MINIMUM_TIMEOUT;
      dev->buffer_status = 0;

      link->priv = dev;
      dev->p_dev = link;

      link->conf.IntType = INT_MEMORY_AND_IO;
      dev_table[i] = link;

      init_waitqueue_head(&dev->devq);
      init_waitqueue_head(&dev->poll_wait);
      init_waitqueue_head(&dev->read_wait);
      init_waitqueue_head(&dev->write_wait);
      setup_timer(&dev->poll_timer, cm4040_do_poll, 0);

      ret = reader_config(link, i);
      if (ret) {
            dev_table[i] = NULL;
            kfree(dev);
            return ret;
      }

      device_create(cmx_class, NULL, MKDEV(major, i), "cmx%d", i);

      return 0;
}

static void reader_detach(struct pcmcia_device *link)
{
      struct reader_dev *dev = link->priv;
      int devno;

      /* find device */
      for (devno = 0; devno < CM_MAX_DEV; devno++) {
            if (dev_table[devno] == link)
                  break;
      }
      if (devno == CM_MAX_DEV)
            return;

      reader_release(link);

      dev_table[devno] = NULL;
      kfree(dev);

      device_destroy(cmx_class, MKDEV(major, devno));

      return;
}

static const struct file_operations reader_fops = {
      .owner            = THIS_MODULE,
      .read       = cm4040_read,
      .write            = cm4040_write,
      .open       = cm4040_open,
      .release    = cm4040_close,
      .poll       = cm4040_poll,
};

static struct pcmcia_device_id cm4040_ids[] = {
      PCMCIA_DEVICE_MANF_CARD(0x0223, 0x0200),
      PCMCIA_DEVICE_PROD_ID12("OMNIKEY", "CardMan 4040",
                        0xE32CDD8C, 0x8F23318B),
      PCMCIA_DEVICE_NULL,
};
MODULE_DEVICE_TABLE(pcmcia, cm4040_ids);

static struct pcmcia_driver reader_driver = {
      .owner            = THIS_MODULE,
      .drv        = {
            .name = "cm4040_cs",
      },
      .probe            = reader_probe,
      .remove           = reader_detach,
      .id_table   = cm4040_ids,
};

static int __init cm4040_init(void)
{
      int rc;

      printk(KERN_INFO "%s\n", version);
      cmx_class = class_create(THIS_MODULE, "cardman_4040");
      if (IS_ERR(cmx_class))
            return PTR_ERR(cmx_class);

      major = register_chrdev(0, DEVICE_NAME, &reader_fops);
      if (major < 0) {
            printk(KERN_WARNING MODULE_NAME
                  ": could not get major number\n");
            class_destroy(cmx_class);
            return major;
      }

      rc = pcmcia_register_driver(&reader_driver);
      if (rc < 0) {
            unregister_chrdev(major, DEVICE_NAME);
            class_destroy(cmx_class);
            return rc;
      }

      return 0;
}

static void __exit cm4040_exit(void)
{
      printk(KERN_INFO MODULE_NAME ": unloading\n");
      pcmcia_unregister_driver(&reader_driver);
      unregister_chrdev(major, DEVICE_NAME);
      class_destroy(cmx_class);
}

module_init(cm4040_init);
module_exit(cm4040_exit);
MODULE_LICENSE("Dual BSD/GPL");

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