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);