} else {
                                        s = NULL;
                                }
-                               ret = down_interruptible(&dev->sem);
+                               ret = mutex_lock_interruptible(&dev->mtx);
                                if( ret ) return ret;
                                if ((s = isdn_net_new(s, NULL))) {
                                        if (copy_to_user(argp, s, strlen(s) + 1)){
                                        }
                                } else
                                        ret = -ENODEV;
-                               up(&dev->sem);
+                               mutex_unlock(&dev->mtx);
                                return ret;
                        case IIOCNETASL:
                                /* Add a slave to a network-interface */
                                                return -EFAULT;
                                } else
                                        return -EINVAL;
-                               ret = down_interruptible(&dev->sem);
+                               ret = mutex_lock_interruptible(&dev->mtx);
                                if( ret ) return ret;
                                if ((s = isdn_net_newslave(bname))) {
                                        if (copy_to_user(argp, s, strlen(s) + 1)){
                                        }
                                } else
                                        ret = -ENODEV;
-                               up(&dev->sem);
+                               mutex_unlock(&dev->mtx);
                                return ret;
                        case IIOCNETDIF:
                                /* Delete a network-interface */
                                if (arg) {
                                        if (copy_from_user(name, argp, sizeof(name)))
                                                return -EFAULT;
-                                       ret = down_interruptible(&dev->sem);
+                                       ret = mutex_lock_interruptible(&dev->mtx);
                                        if( ret ) return ret;
                                        ret = isdn_net_rm(name);
-                                       up(&dev->sem);
+                                       mutex_unlock(&dev->mtx);
                                        return ret;
                                } else
                                        return -EINVAL;
                                if (arg) {
                                        if (copy_from_user(&phone, argp, sizeof(phone)))
                                                return -EFAULT;
-                                       ret = down_interruptible(&dev->sem);
+                                       ret = mutex_lock_interruptible(&dev->mtx);
                                        if( ret ) return ret;
                                        ret = isdn_net_addphone(&phone);
-                                       up(&dev->sem);
+                                       mutex_unlock(&dev->mtx);
                                        return ret;
                                } else
                                        return -EINVAL;
                                if (arg) {
                                        if (copy_from_user(&phone, argp, sizeof(phone)))
                                                return -EFAULT;
-                                       ret = down_interruptible(&dev->sem);
+                                       ret = mutex_lock_interruptible(&dev->mtx);
                                        if( ret ) return ret;
                                        ret = isdn_net_getphones(&phone, argp);
-                                       up(&dev->sem);
+                                       mutex_unlock(&dev->mtx);
                                        return ret;
                                } else
                                        return -EINVAL;
                                if (arg) {
                                        if (copy_from_user(&phone, argp, sizeof(phone)))
                                                return -EFAULT;
-                                       ret = down_interruptible(&dev->sem);
+                                       ret = mutex_lock_interruptible(&dev->mtx);
                                        if( ret ) return ret;
                                        ret = isdn_net_delphone(&phone);
-                                       up(&dev->sem);
+                                       mutex_unlock(&dev->mtx);
                                        return ret;
                                } else
                                        return -EINVAL;
 #ifdef MODULE
        dev->owner = THIS_MODULE;
 #endif
-       init_MUTEX(&dev->sem);
+       mutex_init(&dev->mtx);
        init_waitqueue_head(&dev->info_waitq);
        for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
                dev->drvmap[i] = -1;
 
 #include <linux/etherdevice.h>
 #include <linux/skbuff.h>
 #include <linux/tcp.h>
+#include <linux/mutex.h>
 
 #define ISDN_TTY_MAJOR    43
 #define ISDN_TTYAUX_MAJOR 44
        int               v110emu[ISDN_MAX_CHANNELS]; /* V.110 emulator-mode 0=none */
        atomic_t          v110use[ISDN_MAX_CHANNELS]; /* Usage-Semaphore for stream */
        isdn_v110_stream  *v110[ISDN_MAX_CHANNELS];   /* V.110 private data         */
-       struct semaphore  sem;                        /* serialize list access*/
+       struct mutex      mtx;                        /* serialize list access*/
        unsigned long     global_features;
 } isdn_dev;