/* $Id: divamnt.c,v 1.32.6.10 2005/02/11 19:40:25 armin Exp $
   *
   * Driver for Eicon DIVA Server ISDN cards.
   * Maint module
   *
   * Copyright 2000-2003 by Armin Schindler (mac@melware.de)
   * Copyright 2000-2003 Cytronics & Melware (info@melware.de)
   *
   * This software may be used and distributed according to the terms
   * of the GNU General Public License, incorporated herein by reference.
   */
  
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/kernel.h>
  #include <linux/poll.h>
  #include <linux/mutex.h>
  #include <asm/uaccess.h>
  
  #include "platform.h"
  #include "di_defs.h"
  #include "divasync.h"
  #include "debug_if.h"
  
  static DEFINE_MUTEX(maint_mutex);
  static char *main_revision = "$Revision: 1.32.6.10 $";
  
  static int major;
  
  MODULE_DESCRIPTION("Maint driver for Eicon DIVA Server cards");
  MODULE_AUTHOR("Cytronics & Melware, Eicon Networks");
  MODULE_SUPPORTED_DEVICE("DIVA card driver");
  MODULE_LICENSE("GPL");
  
  static int buffer_length = 128;
  module_param(buffer_length, int, 0);
  static unsigned long diva_dbg_mem = 0;
  module_param(diva_dbg_mem, ulong, 0);
  
  static char *DRIVERNAME =
  	"Eicon DIVA - MAINT module (http://www.melware.net)";
  static char *DRIVERLNAME = "diva_mnt";
  static char *DEVNAME = "DivasMAINT";
  char *DRIVERRELEASE_MNT = "2.0";
  
  static wait_queue_head_t msgwaitq;
  static unsigned long opened;
  static struct timeval start_time;
  
  extern int mntfunc_init(int *, void **, unsigned long);
  extern void mntfunc_finit(void);
  extern int maint_read_write(void __user *buf, int count);
  
  /*
   *  helper functions
   */
  static char *getrev(const char *revision)
  {
  	char *rev;
  	char *p;
  
  	if ((p = strchr(revision, ':'))) {
  		rev = p + 2;
  		p = strchr(rev, '$');
  		*--p = 0;
  	} else
  		rev = "1.0";
  
  	return rev;
  }
  
  /*
   * kernel/user space copy functions
   */
  int diva_os_copy_to_user(void *os_handle, void __user *dst, const void *src,
  			 int length)
  {
  	return (copy_to_user(dst, src, length));
  }
  int diva_os_copy_from_user(void *os_handle, void *dst, const void __user *src,
  			   int length)
  {
  	return (copy_from_user(dst, src, length));
  }
  
  /*
   * get time
   */
  void diva_os_get_time(dword *sec, dword *usec)
  {
  	struct timeval tv;
  
  	do_gettimeofday(&tv);
  
  	if (tv.tv_sec > start_time.tv_sec) {
  		if (start_time.tv_usec > tv.tv_usec) {
  			tv.tv_sec--;
  			tv.tv_usec += 1000000;
  		}
  		*sec = (dword) (tv.tv_sec - start_time.tv_sec);
  		*usec = (dword) (tv.tv_usec - start_time.tv_usec);
  	} else if (tv.tv_sec == start_time.tv_sec) {
  		*sec = 0;
  		if (start_time.tv_usec < tv.tv_usec) {
  			*usec = (dword) (tv.tv_usec - start_time.tv_usec);
  		} else {
  			*usec = 0;
  		}
  	} else {
  		*sec = (dword) tv.tv_sec;
  		*usec = (dword) tv.tv_usec;
  	}
  }
  
  /*
   * device node operations
   */
  static unsigned int maint_poll(struct file *file, poll_table *wait)
  {
  	unsigned int mask = 0;
  
  	poll_wait(file, &msgwaitq, wait);
  	mask = POLLOUT | POLLWRNORM;
  	if (file->private_data || diva_dbg_q_length()) {
  		mask |= POLLIN | POLLRDNORM;
  	}
  	return (mask);
  }
  
  static int maint_open(struct inode *ino, struct file *filep)
  {
  	int ret;
  
  	mutex_lock(&maint_mutex);
  	/* only one open is allowed, so we test
  	   it atomically */
  	if (test_and_set_bit(0, &opened))
  		ret = -EBUSY;
  	else {
  		filep->private_data = NULL;
  		ret = nonseekable_open(ino, filep);
  	}
  	mutex_unlock(&maint_mutex);
  	return ret;
  }
  
  static int maint_close(struct inode *ino, struct file *filep)
  {
  	if (filep->private_data) {
  		diva_os_free(0, filep->private_data);
  		filep->private_data = NULL;
  	}
  
  	/* clear 'used' flag */
  	clear_bit(0, &opened);
  
  	return (0);
  }
  
  static ssize_t divas_maint_write(struct file *file, const char __user *buf,
  				 size_t count, loff_t *ppos)
  {
  	return (maint_read_write((char __user *) buf, (int) count));
  }
  
  static ssize_t divas_maint_read(struct file *file, char __user *buf,
  				size_t count, loff_t *ppos)
  {
  	return (maint_read_write(buf, (int) count));
  }
  
  static const struct file_operations divas_maint_fops = {
  	.owner   = THIS_MODULE,
  	.llseek  = no_llseek,
  	.read    = divas_maint_read,
  	.write   = divas_maint_write,
  	.poll    = maint_poll,
  	.open    = maint_open,
  	.release = maint_close
  };
  
  static void divas_maint_unregister_chrdev(void)
  {
  	unregister_chrdev(major, DEVNAME);
  }
  
  static int __init divas_maint_register_chrdev(void)
  {
  	if ((major = register_chrdev(0, DEVNAME, &divas_maint_fops)) < 0)
  	{
  		printk(KERN_ERR "%s: failed to create /dev entry.
  ",
  		       DRIVERLNAME);
  		return (0);
  	}
  
  	return (1);
  }
  
  /*
   * wake up reader
   */
  void diva_maint_wakeup_read(void)
  {
  	wake_up_interruptible(&msgwaitq);
  }
  
  /*
   *  Driver Load
   */
  static int __init maint_init(void)
  {
  	char tmprev[50];
  	int ret = 0;
  	void *buffer = NULL;
  
  	do_gettimeofday(&start_time);
  	init_waitqueue_head(&msgwaitq);
  
  	printk(KERN_INFO "%s
  ", DRIVERNAME);
  	printk(KERN_INFO "%s: Rel:%s  Rev:", DRIVERLNAME, DRIVERRELEASE_MNT);
  	strcpy(tmprev, main_revision);
  	printk("%s  Build: %s 
  ", getrev(tmprev), DIVA_BUILD);
  
  	if (!divas_maint_register_chrdev()) {
  		ret = -EIO;
  		goto out;
  	}
  
  	if (!(mntfunc_init(&buffer_length, &buffer, diva_dbg_mem))) {
  		printk(KERN_ERR "%s: failed to connect to DIDD.
  ",
  		       DRIVERLNAME);
  		divas_maint_unregister_chrdev();
  		ret = -EIO;
  		goto out;
  	}
  
  	printk(KERN_INFO "%s: trace buffer = %p - %d kBytes, %s (Major: %d)
  ",
  	       DRIVERLNAME, buffer, (buffer_length / 1024),
  	       (diva_dbg_mem == 0) ? "internal" : "external", major);
  
  out:
  	return (ret);
  }
  
  /*
  **  Driver Unload
  */
  static void __exit maint_exit(void)
  {
  	divas_maint_unregister_chrdev();
  	mntfunc_finit();
  
  	printk(KERN_INFO "%s: module unloaded.
  ", DRIVERLNAME);
  }
  
  module_init(maint_init);
  module_exit(maint_exit);