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path: root/drivers/isdn/mISDN/timerdev.c
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Diffstat (limited to 'drivers/isdn/mISDN/timerdev.c')
-rw-r--r--drivers/isdn/mISDN/timerdev.c301
1 files changed, 301 insertions, 0 deletions
diff --git a/drivers/isdn/mISDN/timerdev.c b/drivers/isdn/mISDN/timerdev.c
new file mode 100644
index 00000000000..b5fabc7019d
--- /dev/null
+++ b/drivers/isdn/mISDN/timerdev.c
@@ -0,0 +1,301 @@
+/*
+ *
+ * general timer device for using in ISDN stacks
+ *
+ * Author Karsten Keil <kkeil@novell.com>
+ *
+ * Copyright 2008 by Karsten Keil <kkeil@novell.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/poll.h>
+#include <linux/vmalloc.h>
+#include <linux/timer.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/mISDNif.h>
+
+static int *debug;
+
+
+struct mISDNtimerdev {
+ int next_id;
+ struct list_head pending;
+ struct list_head expired;
+ wait_queue_head_t wait;
+ u_int work;
+ spinlock_t lock; /* protect lists */
+};
+
+struct mISDNtimer {
+ struct list_head list;
+ struct mISDNtimerdev *dev;
+ struct timer_list tl;
+ int id;
+};
+
+static int
+mISDN_open(struct inode *ino, struct file *filep)
+{
+ struct mISDNtimerdev *dev;
+
+ if (*debug & DEBUG_TIMER)
+ printk(KERN_DEBUG "%s(%p,%p)\n", __func__, ino, filep);
+ dev = kmalloc(sizeof(struct mISDNtimerdev) , GFP_KERNEL);
+ if (!dev)
+ return -ENOMEM;
+ dev->next_id = 1;
+ INIT_LIST_HEAD(&dev->pending);
+ INIT_LIST_HEAD(&dev->expired);
+ spin_lock_init(&dev->lock);
+ dev->work = 0;
+ init_waitqueue_head(&dev->wait);
+ filep->private_data = dev;
+ __module_get(THIS_MODULE);
+ return 0;
+}
+
+static int
+mISDN_close(struct inode *ino, struct file *filep)
+{
+ struct mISDNtimerdev *dev = filep->private_data;
+ struct mISDNtimer *timer, *next;
+
+ if (*debug & DEBUG_TIMER)
+ printk(KERN_DEBUG "%s(%p,%p)\n", __func__, ino, filep);
+ list_for_each_entry_safe(timer, next, &dev->pending, list) {
+ del_timer(&timer->tl);
+ kfree(timer);
+ }
+ list_for_each_entry_safe(timer, next, &dev->expired, list) {
+ kfree(timer);
+ }
+ kfree(dev);
+ module_put(THIS_MODULE);
+ return 0;
+}
+
+static ssize_t
+mISDN_read(struct file *filep, char *buf, size_t count, loff_t *off)
+{
+ struct mISDNtimerdev *dev = filep->private_data;
+ struct mISDNtimer *timer;
+ u_long flags;
+ int ret = 0;
+
+ if (*debug & DEBUG_TIMER)
+ printk(KERN_DEBUG "%s(%p, %p, %d, %p)\n", __func__,
+ filep, buf, (int)count, off);
+ if (*off != filep->f_pos)
+ return -ESPIPE;
+
+ if (list_empty(&dev->expired) && (dev->work == 0)) {
+ if (filep->f_flags & O_NONBLOCK)
+ return -EAGAIN;
+ wait_event_interruptible(dev->wait, (dev->work ||
+ !list_empty(&dev->expired)));
+ if (signal_pending(current))
+ return -ERESTARTSYS;
+ }
+ if (count < sizeof(int))
+ return -ENOSPC;
+ if (dev->work)
+ dev->work = 0;
+ if (!list_empty(&dev->expired)) {
+ spin_lock_irqsave(&dev->lock, flags);
+ timer = (struct mISDNtimer *)dev->expired.next;
+ list_del(&timer->list);
+ spin_unlock_irqrestore(&dev->lock, flags);
+ if (put_user(timer->id, (int *)buf))
+ ret = -EFAULT;
+ else
+ ret = sizeof(int);
+ kfree(timer);
+ }
+ return ret;
+}
+
+static loff_t
+mISDN_llseek(struct file *filep, loff_t offset, int orig)
+{
+ return -ESPIPE;
+}
+
+static ssize_t
+mISDN_write(struct file *filep, const char *buf, size_t count, loff_t *off)
+{
+ return -EOPNOTSUPP;
+}
+
+static unsigned int
+mISDN_poll(struct file *filep, poll_table *wait)
+{
+ struct mISDNtimerdev *dev = filep->private_data;
+ unsigned int mask = POLLERR;
+
+ if (*debug & DEBUG_TIMER)
+ printk(KERN_DEBUG "%s(%p, %p)\n", __func__, filep, wait);
+ if (dev) {
+ poll_wait(filep, &dev->wait, wait);
+ mask = 0;
+ if (dev->work || !list_empty(&dev->expired))
+ mask |= (POLLIN | POLLRDNORM);
+ if (*debug & DEBUG_TIMER)
+ printk(KERN_DEBUG "%s work(%d) empty(%d)\n", __func__,
+ dev->work, list_empty(&dev->expired));
+ }
+ return mask;
+}
+
+static void
+dev_expire_timer(struct mISDNtimer *timer)
+{
+ u_long flags;
+
+ spin_lock_irqsave(&timer->dev->lock, flags);
+ list_del(&timer->list);
+ list_add_tail(&timer->list, &timer->dev->expired);
+ spin_unlock_irqrestore(&timer->dev->lock, flags);
+ wake_up_interruptible(&timer->dev->wait);
+}
+
+static int
+misdn_add_timer(struct mISDNtimerdev *dev, int timeout)
+{
+ int id;
+ u_long flags;
+ struct mISDNtimer *timer;
+
+ if (!timeout) {
+ dev->work = 1;
+ wake_up_interruptible(&dev->wait);
+ id = 0;
+ } else {
+ timer = kzalloc(sizeof(struct mISDNtimer), GFP_KERNEL);
+ if (!timer)
+ return -ENOMEM;
+ spin_lock_irqsave(&dev->lock, flags);
+ timer->id = dev->next_id++;
+ if (dev->next_id < 0)
+ dev->next_id = 1;
+ list_add_tail(&timer->list, &dev->pending);
+ spin_unlock_irqrestore(&dev->lock, flags);
+ timer->dev = dev;
+ timer->tl.data = (long)timer;
+ timer->tl.function = (void *) dev_expire_timer;
+ init_timer(&timer->tl);
+ timer->tl.expires = jiffies + ((HZ * (u_long)timeout) / 1000);
+ add_timer(&timer->tl);
+ id = timer->id;
+ }
+ return id;
+}
+
+static int
+misdn_del_timer(struct mISDNtimerdev *dev, int id)
+{
+ u_long flags;
+ struct mISDNtimer *timer;
+ int ret = 0;
+
+ spin_lock_irqsave(&dev->lock, flags);
+ list_for_each_entry(timer, &dev->pending, list) {
+ if (timer->id == id) {
+ list_del_init(&timer->list);
+ del_timer(&timer->tl);
+ ret = timer->id;
+ kfree(timer);
+ goto unlock;
+ }
+ }
+unlock:
+ spin_unlock_irqrestore(&dev->lock, flags);
+ return ret;
+}
+
+static int
+mISDN_ioctl(struct inode *inode, struct file *filep, unsigned int cmd,
+ unsigned long arg)
+{
+ struct mISDNtimerdev *dev = filep->private_data;
+ int id, tout, ret = 0;
+
+
+ if (*debug & DEBUG_TIMER)
+ printk(KERN_DEBUG "%s(%p, %x, %lx)\n", __func__,
+ filep, cmd, arg);
+ switch (cmd) {
+ case IMADDTIMER:
+ if (get_user(tout, (int __user *)arg)) {
+ ret = -EFAULT;
+ break;
+ }
+ id = misdn_add_timer(dev, tout);
+ if (*debug & DEBUG_TIMER)
+ printk(KERN_DEBUG "%s add %d id %d\n", __func__,
+ tout, id);
+ if (id < 0) {
+ ret = id;
+ break;
+ }
+ if (put_user(id, (int __user *)arg))
+ ret = -EFAULT;
+ break;
+ case IMDELTIMER:
+ if (get_user(id, (int __user *)arg)) {
+ ret = -EFAULT;
+ break;
+ }
+ if (*debug & DEBUG_TIMER)
+ printk(KERN_DEBUG "%s del id %d\n", __func__, id);
+ id = misdn_del_timer(dev, id);
+ if (put_user(id, (int __user *)arg))
+ ret = -EFAULT;
+ break;
+ default:
+ ret = -EINVAL;
+ }
+ return ret;
+}
+
+static struct file_operations mISDN_fops = {
+ .llseek = mISDN_llseek,
+ .read = mISDN_read,
+ .write = mISDN_write,
+ .poll = mISDN_poll,
+ .ioctl = mISDN_ioctl,
+ .open = mISDN_open,
+ .release = mISDN_close,
+};
+
+static struct miscdevice mISDNtimer = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "mISDNtimer",
+ .fops = &mISDN_fops,
+};
+
+int
+mISDN_inittimer(int *deb)
+{
+ int err;
+
+ debug = deb;
+ err = misc_register(&mISDNtimer);
+ if (err)
+ printk(KERN_WARNING "mISDN: Could not register timer device\n");
+ return err;
+}
+
+void mISDN_timer_cleanup(void)
+{
+ misc_deregister(&mISDNtimer);
+}