1 files changed, 835 insertions, 0 deletions

diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c
new file mode 100644
index 000000000000..fd630cec0e79
--- /dev/null
+++ b/drivers/w1/w1.c
@@ -0,0 +1,835 @@
+/*
+ * 	w1.c
+ *
+ * Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
+ * 
+ *
+ * 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.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/list.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/timer.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+
+#include <asm/atomic.h>
+
+#include "w1.h"
+#include "w1_io.h"
+#include "w1_log.h"
+#include "w1_int.h"
+#include "w1_family.h"
+#include "w1_netlink.h"
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Evgeniy Polyakov <johnpol@2ka.mipt.ru>");
+MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol.");
+
+static int w1_timeout = 10;
+int w1_max_slave_count = 10;
+int w1_max_slave_ttl = 10;
+
+module_param_named(timeout, w1_timeout, int, 0);
+module_param_named(max_slave_count, w1_max_slave_count, int, 0);
+module_param_named(slave_ttl, w1_max_slave_ttl, int, 0);
+
+DEFINE_SPINLOCK(w1_mlock);
+LIST_HEAD(w1_masters);
+
+static pid_t control_thread;
+static int control_needs_exit;
+static DECLARE_COMPLETION(w1_control_complete);
+
+static int w1_master_match(struct device *dev, struct device_driver *drv)
+{
+	return 1;
+}
+
+static int w1_master_probe(struct device *dev)
+{
+	return -ENODEV;
+}
+
+static int w1_master_remove(struct device *dev)
+{
+	return 0;
+}
+
+static void w1_master_release(struct device *dev)
+{
+	struct w1_master *md = container_of(dev, struct w1_master, dev);
+
+	complete(&md->dev_released);
+}
+
+static void w1_slave_release(struct device *dev)
+{
+	struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
+
+	complete(&sl->dev_released);
+}
+
+static ssize_t w1_default_read_name(struct device *dev, char *buf)
+{
+	return sprintf(buf, "No family registered.\n");
+}
+
+static ssize_t w1_default_read_bin(struct kobject *kobj, char *buf, loff_t off,
+		     size_t count)
+{
+	return sprintf(buf, "No family registered.\n");
+}
+
+static struct bus_type w1_bus_type = {
+	.name = "w1",
+	.match = w1_master_match,
+};
+
+struct device_driver w1_driver = {
+	.name = "w1_driver",
+	.bus = &w1_bus_type,
+	.probe = w1_master_probe,
+	.remove = w1_master_remove,
+};
+
+struct device w1_device = {
+	.parent = NULL,
+	.bus = &w1_bus_type,
+	.bus_id = "w1 bus master",
+	.driver = &w1_driver,
+	.release = &w1_master_release
+};
+
+static struct device_attribute w1_slave_attribute = {
+	.attr = {
+			.name = "name",
+			.mode = S_IRUGO,
+			.owner = THIS_MODULE
+	},
+	.show = &w1_default_read_name,
+};
+
+static struct device_attribute w1_slave_attribute_val = {
+	.attr = {
+			.name = "value",
+			.mode = S_IRUGO,
+			.owner = THIS_MODULE
+	},
+	.show = &w1_default_read_name,
+};
+
+static ssize_t w1_master_attribute_show_name(struct device *dev, char *buf)
+{
+	struct w1_master *md = container_of (dev, struct w1_master, dev);
+	ssize_t count;
+	
+	if (down_interruptible (&md->mutex))
+		return -EBUSY;
+
+	count = sprintf(buf, "%s\n", md->name);
+	
+	up(&md->mutex);
+
+	return count;
+}
+
+static ssize_t w1_master_attribute_show_pointer(struct device *dev, char *buf)
+{
+	struct w1_master *md = container_of(dev, struct w1_master, dev);
+	ssize_t count;
+	
+	if (down_interruptible(&md->mutex))
+		return -EBUSY;
+
+	count = sprintf(buf, "0x%p\n", md->bus_master);
+	
+	up(&md->mutex);
+	return count;
+}
+
+static ssize_t w1_master_attribute_show_timeout(struct device *dev, char *buf)
+{
+	ssize_t count;
+	count = sprintf(buf, "%d\n", w1_timeout);
+	return count;
+}
+
+static ssize_t w1_master_attribute_show_max_slave_count(struct device *dev, char *buf)
+{
+	struct w1_master *md = container_of(dev, struct w1_master, dev);
+	ssize_t count;
+	
+	if (down_interruptible(&md->mutex))
+		return -EBUSY;
+
+	count = sprintf(buf, "%d\n", md->max_slave_count);
+	
+	up(&md->mutex);
+	return count;
+}
+
+static ssize_t w1_master_attribute_show_attempts(struct device *dev, char *buf)
+{
+	struct w1_master *md = container_of(dev, struct w1_master, dev);
+	ssize_t count;
+	
+	if (down_interruptible(&md->mutex))
+		return -EBUSY;
+
+	count = sprintf(buf, "%lu\n", md->attempts);
+	
+	up(&md->mutex);
+	return count;
+}
+
+static ssize_t w1_master_attribute_show_slave_count(struct device *dev, char *buf)
+{
+	struct w1_master *md = container_of(dev, struct w1_master, dev);
+	ssize_t count;
+	
+	if (down_interruptible(&md->mutex))
+		return -EBUSY;
+
+	count = sprintf(buf, "%d\n", md->slave_count);
+	
+	up(&md->mutex);
+	return count;
+}
+
+static ssize_t w1_master_attribute_show_slaves(struct device *dev, char *buf)
+
+{
+	struct w1_master *md = container_of(dev, struct w1_master, dev);
+	int c = PAGE_SIZE;
+
+	if (down_interruptible(&md->mutex))
+		return -EBUSY;
+
+	if (md->slave_count == 0)
+		c -= snprintf(buf + PAGE_SIZE - c, c, "not found.\n");
+	else {
+		struct list_head *ent, *n;
+		struct w1_slave *sl;
+
+		list_for_each_safe(ent, n, &md->slist) {
+			sl = list_entry(ent, struct w1_slave, w1_slave_entry);
+
+ 			c -= snprintf(buf + PAGE_SIZE - c, c, "%s\n", sl->name);
+		}
+	}
+
+	up(&md->mutex);
+
+	return PAGE_SIZE - c;
+}
+
+static struct device_attribute w1_master_attribute_slaves = {
+	.attr = {
+ 			.name = "w1_master_slaves",
+			.mode = S_IRUGO,
+			.owner = THIS_MODULE,
+	},
+ 	.show = &w1_master_attribute_show_slaves,
+};
+static struct device_attribute w1_master_attribute_slave_count = {
+	.attr = {
+			.name = "w1_master_slave_count",
+			.mode = S_IRUGO,
+			.owner = THIS_MODULE
+	},
+	.show = &w1_master_attribute_show_slave_count,
+};
+static struct device_attribute w1_master_attribute_attempts = {
+	.attr = {
+			.name = "w1_master_attempts",
+			.mode = S_IRUGO,
+			.owner = THIS_MODULE
+	},
+	.show = &w1_master_attribute_show_attempts,
+};
+static struct device_attribute w1_master_attribute_max_slave_count = {
+	.attr = {
+			.name = "w1_master_max_slave_count",
+			.mode = S_IRUGO,
+			.owner = THIS_MODULE
+	},
+	.show = &w1_master_attribute_show_max_slave_count,
+};
+static struct device_attribute w1_master_attribute_timeout = {
+	.attr = {
+			.name = "w1_master_timeout",
+			.mode = S_IRUGO,
+			.owner = THIS_MODULE
+	},
+	.show = &w1_master_attribute_show_timeout,
+};
+static struct device_attribute w1_master_attribute_pointer = {
+	.attr = {
+			.name = "w1_master_pointer",
+			.mode = S_IRUGO,
+			.owner = THIS_MODULE
+	},
+	.show = &w1_master_attribute_show_pointer,
+};
+static struct device_attribute w1_master_attribute_name = {
+	.attr = {
+			.name = "w1_master_name",
+			.mode = S_IRUGO,
+			.owner = THIS_MODULE
+	},
+	.show = &w1_master_attribute_show_name,
+};
+
+static struct bin_attribute w1_slave_bin_attribute = {
+	.attr = {
+		 	.name = "w1_slave",
+		 	.mode = S_IRUGO,
+			.owner = THIS_MODULE,
+	},
+	.size = W1_SLAVE_DATA_SIZE,
+	.read = &w1_default_read_bin,
+};
+
+static int __w1_attach_slave_device(struct w1_slave *sl)
+{
+	int err;
+
+	sl->dev.parent = &sl->master->dev;
+	sl->dev.driver = sl->master->driver;
+	sl->dev.bus = &w1_bus_type;
+	sl->dev.release = &w1_slave_release;
+
+	snprintf(&sl->dev.bus_id[0], sizeof(sl->dev.bus_id),
+		  "%02x-%012llx",
+		  (unsigned int) sl->reg_num.family,
+		  (unsigned long long) sl->reg_num.id);
+	snprintf (&sl->name[0], sizeof(sl->name),
+		  "%02x-%012llx",
+		  (unsigned int) sl->reg_num.family,
+		  (unsigned long long) sl->reg_num.id);
+
+	dev_dbg(&sl->dev, "%s: registering %s.\n", __func__,
+		&sl->dev.bus_id[0]);
+
+	err = device_register(&sl->dev);
+	if (err < 0) {
+		dev_err(&sl->dev,
+			 "Device registration [%s] failed. err=%d\n",
+			 sl->dev.bus_id, err);
+		return err;
+	}
+
+	memcpy(&sl->attr_bin, &w1_slave_bin_attribute, sizeof(sl->attr_bin));
+	memcpy(&sl->attr_name, &w1_slave_attribute, sizeof(sl->attr_name));
+	memcpy(&sl->attr_val, &w1_slave_attribute_val, sizeof(sl->attr_val));
+	
+	sl->attr_bin.read = sl->family->fops->rbin;
+	sl->attr_name.show = sl->family->fops->rname;
+	sl->attr_val.show = sl->family->fops->rval;
+	sl->attr_val.attr.name = sl->family->fops->rvalname;
+
+	err = device_create_file(&sl->dev, &sl->attr_name);
+	if (err < 0) {
+		dev_err(&sl->dev,
+			 "sysfs file creation for [%s] failed. err=%d\n",
+			 sl->dev.bus_id, err);
+		device_unregister(&sl->dev);
+		return err;
+	}
+
+	err = device_create_file(&sl->dev, &sl->attr_val);
+	if (err < 0) {
+		dev_err(&sl->dev,
+			 "sysfs file creation for [%s] failed. err=%d\n",
+			 sl->dev.bus_id, err);
+		device_remove_file(&sl->dev, &sl->attr_name);
+		device_unregister(&sl->dev);
+		return err;
+	}
+
+	err = sysfs_create_bin_file(&sl->dev.kobj, &sl->attr_bin);
+	if (err < 0) {
+		dev_err(&sl->dev,
+			 "sysfs file creation for [%s] failed. err=%d\n",
+			 sl->dev.bus_id, err);
+		device_remove_file(&sl->dev, &sl->attr_name);
+		device_remove_file(&sl->dev, &sl->attr_val);
+		device_unregister(&sl->dev);
+		return err;
+	}
+
+	list_add_tail(&sl->w1_slave_entry, &sl->master->slist);
+
+	return 0;
+}
+
+static int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
+{
+	struct w1_slave *sl;
+	struct w1_family *f;
+	int err;
+	struct w1_netlink_msg msg;
+
+	sl = kmalloc(sizeof(struct w1_slave), GFP_KERNEL);
+	if (!sl) {
+		dev_err(&dev->dev,
+			 "%s: failed to allocate new slave device.\n",
+			 __func__);
+		return -ENOMEM;
+	}
+
+	memset(sl, 0, sizeof(*sl));
+
+	sl->owner = THIS_MODULE;
+	sl->master = dev;
+	set_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags);
+
+	memcpy(&sl->reg_num, rn, sizeof(sl->reg_num));
+	atomic_set(&sl->refcnt, 0);
+	init_completion(&sl->dev_released);
+
+	spin_lock(&w1_flock);
+	f = w1_family_registered(rn->family);
+	if (!f) {
+		spin_unlock(&w1_flock);
+		dev_info(&dev->dev, "Family %x for %02x.%012llx.%02x is not registered.\n",
+			  rn->family, rn->family,
+			  (unsigned long long)rn->id, rn->crc);
+		kfree(sl);
+		return -ENODEV;
+	}
+	__w1_family_get(f);
+	spin_unlock(&w1_flock);
+
+	sl->family = f;
+
+
+	err = __w1_attach_slave_device(sl);
+	if (err < 0) {
+		dev_err(&dev->dev, "%s: Attaching %s failed.\n", __func__,
+			 sl->name);
+		w1_family_put(sl->family);
+		kfree(sl);
+		return err;
+	}
+
+	sl->ttl = dev->slave_ttl;
+	dev->slave_count++;
+
+	memcpy(&msg.id.id, rn, sizeof(msg.id.id));
+	msg.type = W1_SLAVE_ADD;
+	w1_netlink_send(dev, &msg);
+
+	return 0;
+}
+
+static void w1_slave_detach(struct w1_slave *sl)
+{
+	struct w1_netlink_msg msg;
+	
+	dev_info(&sl->dev, "%s: detaching %s.\n", __func__, sl->name);
+
+	while (atomic_read(&sl->refcnt)) {
+		printk(KERN_INFO "Waiting for %s to become free: refcnt=%d.\n",
+				sl->name, atomic_read(&sl->refcnt));
+
+		if (msleep_interruptible(1000))
+			flush_signals(current);
+	}
+
+	sysfs_remove_bin_file (&sl->dev.kobj, &sl->attr_bin);
+	device_remove_file(&sl->dev, &sl->attr_name);
+	device_remove_file(&sl->dev, &sl->attr_val);
+	device_unregister(&sl->dev);
+	w1_family_put(sl->family);
+
+	memcpy(&msg.id.id, &sl->reg_num, sizeof(msg.id.id));
+	msg.type = W1_SLAVE_REMOVE;
+	w1_netlink_send(sl->master, &msg);
+}
+
+static struct w1_master *w1_search_master(unsigned long data)
+{
+	struct w1_master *dev;
+	int found = 0;
+	
+	spin_lock_irq(&w1_mlock);
+	list_for_each_entry(dev, &w1_masters, w1_master_entry) {
+		if (dev->bus_master->data == data) {
+			found = 1;
+			atomic_inc(&dev->refcnt);
+			break;
+		}
+	}
+	spin_unlock_irq(&w1_mlock);
+
+	return (found)?dev:NULL;
+}
+
+void w1_slave_found(unsigned long data, u64 rn)
+{
+	int slave_count;
+	struct w1_slave *sl;
+	struct list_head *ent;
+	struct w1_reg_num *tmp;
+	int family_found = 0;
+	struct w1_master *dev;
+
+	dev = w1_search_master(data);
+	if (!dev) {
+		printk(KERN_ERR "Failed to find w1 master device for data %08lx, it is impossible.\n",
+				data);
+		return;
+	}
+	
+	tmp = (struct w1_reg_num *) &rn;
+
+	slave_count = 0;
+	list_for_each(ent, &dev->slist) {
+
+		sl = list_entry(ent, struct w1_slave, w1_slave_entry);
+
+		if (sl->reg_num.family == tmp->family &&
+		    sl->reg_num.id == tmp->id &&
+		    sl->reg_num.crc == tmp->crc) {
+			set_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags);
+			break;
+		}
+		else if (sl->reg_num.family == tmp->family) {
+			family_found = 1;
+			break;
+		}
+
+		slave_count++;
+	}
+
+		if (slave_count == dev->slave_count && rn ) {
+			tmp = cpu_to_le64(rn);
+			if(((rn >> 56) & 0xff) == w1_calc_crc8((u8 *)&tmp, 7))
+				w1_attach_slave_device(dev, (struct w1_reg_num *) &rn);
+	}
+			
+	atomic_dec(&dev->refcnt);
+}
+
+void w1_search(struct w1_master *dev)
+{
+	u64 last, rn, tmp;
+	int i, count = 0;
+	int last_family_desc, last_zero, last_device;
+	int search_bit, id_bit, comp_bit, desc_bit;
+
+	search_bit = id_bit = comp_bit = 0;
+	rn = tmp = last = 0;
+	last_device = last_zero = last_family_desc = 0;
+
+	desc_bit = 64;
+
+	while (!(id_bit && comp_bit) && !last_device
+		&& count++ < dev->max_slave_count) {
+		last = rn;
+		rn = 0;
+
+		last_family_desc = 0;
+
+		/*
+		 * Reset bus and all 1-wire device state machines
+		 * so they can respond to our requests.
+		 *
+		 * Return 0 - device(s) present, 1 - no devices present.
+		 */
+		if (w1_reset_bus(dev)) {
+			dev_info(&dev->dev, "No devices present on the wire.\n");
+			break;
+		}
+
+#if 1
+		w1_write_8(dev, W1_SEARCH);
+		for (i = 0; i < 64; ++i) {
+			/*
+			 * Read 2 bits from bus.
+			 * All who don't sleep must send ID bit and COMPLEMENT ID bit.
+			 * They actually are ANDed between all senders.
+			 */
+			id_bit = w1_touch_bit(dev, 1);
+			comp_bit = w1_touch_bit(dev, 1);
+
+			if (id_bit && comp_bit)
+				break;
+
+			if (id_bit == 0 && comp_bit == 0) {
+				if (i == desc_bit)
+					search_bit = 1;
+				else if (i > desc_bit)
+					search_bit = 0;
+				else
+					search_bit = ((last >> i) & 0x1);
+
+				if (search_bit == 0) {
+					last_zero = i;
+					if (last_zero < 9)
+						last_family_desc = last_zero;
+				}
+
+			}
+			else
+				search_bit = id_bit;
+
+			tmp = search_bit;
+			rn |= (tmp << i);
+
+			/*
+			 * Write 1 bit to bus
+			 * and make all who don't have "search_bit" in "i"'th position
+			 * in it's registration number sleep.
+			 */
+			if (dev->bus_master->touch_bit)
+				w1_touch_bit(dev, search_bit);
+			else
+				w1_write_bit(dev, search_bit);
+
+		}
+#endif
+
+		if (desc_bit == last_zero)
+			last_device = 1;
+
+		desc_bit = last_zero;
+	
+		w1_slave_found(dev->bus_master->data, rn);
+	}
+}
+
+int w1_create_master_attributes(struct w1_master *dev)
+{
+	if (	device_create_file(&dev->dev, &w1_master_attribute_slaves) < 0 ||
+		device_create_file(&dev->dev, &w1_master_attribute_slave_count) < 0 ||
+		device_create_file(&dev->dev, &w1_master_attribute_attempts) < 0 ||
+		device_create_file(&dev->dev, &w1_master_attribute_max_slave_count) < 0 ||
+		device_create_file(&dev->dev, &w1_master_attribute_timeout) < 0||
+		device_create_file(&dev->dev, &w1_master_attribute_pointer) < 0||
+		device_create_file(&dev->dev, &w1_master_attribute_name) < 0)
+		return -EINVAL;
+
+	return 0;
+}
+
+void w1_destroy_master_attributes(struct w1_master *dev)
+{
+	device_remove_file(&dev->dev, &w1_master_attribute_slaves);
+	device_remove_file(&dev->dev, &w1_master_attribute_slave_count);
+	device_remove_file(&dev->dev, &w1_master_attribute_attempts);
+	device_remove_file(&dev->dev, &w1_master_attribute_max_slave_count);
+	device_remove_file(&dev->dev, &w1_master_attribute_timeout);
+	device_remove_file(&dev->dev, &w1_master_attribute_pointer);
+	device_remove_file(&dev->dev, &w1_master_attribute_name);
+}
+
+
+int w1_control(void *data)
+{
+	struct w1_slave *sl;
+	struct w1_master *dev;
+	struct list_head *ent, *ment, *n, *mn;
+	int err, have_to_wait = 0;
+
+	daemonize("w1_control");
+	allow_signal(SIGTERM);
+
+	while (!control_needs_exit || have_to_wait) {
+		have_to_wait = 0;
+
+		try_to_freeze(PF_FREEZE);
+		msleep_interruptible(w1_timeout * 1000);
+
+		if (signal_pending(current))
+			flush_signals(current);
+
+		list_for_each_safe(ment, mn, &w1_masters) {
+			dev = list_entry(ment, struct w1_master, w1_master_entry);
+
+			if (!control_needs_exit && !dev->need_exit)
+				continue;
+			/*
+			 * Little race: we can create thread but not set the flag.
+			 * Get a chance for external process to set flag up.
+			 */
+			if (!dev->initialized) {
+				have_to_wait = 1;
+				continue;
+			}
+
+			spin_lock(&w1_mlock);
+			list_del(&dev->w1_master_entry);
+			spin_unlock(&w1_mlock);
+
+			if (control_needs_exit) {
+				dev->need_exit = 1;
+
+				err = kill_proc(dev->kpid, SIGTERM, 1);
+				if (err)
+					dev_err(&dev->dev,
+						 "Failed to send signal to w1 kernel thread %d.\n",
+						 dev->kpid);
+			}
+
+			wait_for_completion(&dev->dev_exited);
+
+			list_for_each_safe(ent, n, &dev->slist) {
+				sl = list_entry(ent, struct w1_slave, w1_slave_entry);
+
+				if (!sl)
+					dev_warn(&dev->dev,
+						  "%s: slave entry is NULL.\n",
+						  __func__);
+				else {
+					list_del(&sl->w1_slave_entry);
+
+					w1_slave_detach(sl);
+					kfree(sl);
+				}
+			}
+			w1_destroy_master_attributes(dev);
+			atomic_dec(&dev->refcnt);
+		}
+	}
+
+	complete_and_exit(&w1_control_complete, 0);
+}
+
+int w1_process(void *data)
+{
+	struct w1_master *dev = (struct w1_master *) data;
+	struct list_head *ent, *n;
+	struct w1_slave *sl;
+
+	daemonize("%s", dev->name);
+	allow_signal(SIGTERM);
+
+	while (!dev->need_exit) {
+		try_to_freeze(PF_FREEZE);
+		msleep_interruptible(w1_timeout * 1000);
+
+		if (signal_pending(current))
+			flush_signals(current);
+
+		if (dev->need_exit)
+			break;
+
+		if (!dev->initialized)
+			continue;
+
+		if (down_interruptible(&dev->mutex))
+			continue;
+
+		list_for_each_safe(ent, n, &dev->slist) {
+			sl = list_entry(ent, struct w1_slave, w1_slave_entry);
+
+			if (sl)
+				clear_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags);
+		}
+		
+		w1_search_devices(dev, w1_slave_found);
+
+		list_for_each_safe(ent, n, &dev->slist) {
+			sl = list_entry(ent, struct w1_slave, w1_slave_entry);
+
+			if (sl && !test_bit(W1_SLAVE_ACTIVE, (unsigned long *)&sl->flags) && !--sl->ttl) {
+				list_del (&sl->w1_slave_entry);
+
+				w1_slave_detach (sl);
+				kfree (sl);
+
+				dev->slave_count--;
+			}
+			else if (test_bit(W1_SLAVE_ACTIVE, (unsigned long *)&sl->flags))
+				sl->ttl = dev->slave_ttl;
+		}
+		up(&dev->mutex);
+	}
+
+	atomic_dec(&dev->refcnt);
+	complete_and_exit(&dev->dev_exited, 0);
+
+	return 0;
+}
+
+int w1_init(void)
+{
+	int retval;
+
+	printk(KERN_INFO "Driver for 1-wire Dallas network protocol.\n");
+
+	retval = bus_register(&w1_bus_type);
+	if (retval) {
+		printk(KERN_ERR "Failed to register bus. err=%d.\n", retval);
+		goto err_out_exit_init;
+	}
+
+	retval = driver_register(&w1_driver);
+	if (retval) {
+		printk(KERN_ERR
+			"Failed to register master driver. err=%d.\n",
+			retval);
+		goto err_out_bus_unregister;
+	}
+
+	control_thread = kernel_thread(&w1_control, NULL, 0);
+	if (control_thread < 0) {
+		printk(KERN_ERR "Failed to create control thread. err=%d\n",
+			control_thread);
+		retval = control_thread;
+		goto err_out_driver_unregister;
+	}
+
+	return 0;
+
+err_out_driver_unregister:
+	driver_unregister(&w1_driver);
+
+err_out_bus_unregister:
+	bus_unregister(&w1_bus_type);
+
+err_out_exit_init:
+	return retval;
+}
+
+void w1_fini(void)
+{
+	struct w1_master *dev;
+	struct list_head *ent, *n;
+
+	list_for_each_safe(ent, n, &w1_masters) {
+		dev = list_entry(ent, struct w1_master, w1_master_entry);
+		__w1_remove_master_device(dev);
+	}
+
+	control_needs_exit = 1;
+
+	wait_for_completion(&w1_control_complete);
+
+	driver_unregister(&w1_driver);
+	bus_unregister(&w1_bus_type);
+}
+
+module_init(w1_init);
+module_exit(w1_fini);