W1: be able to manually add and remove slaves
[safe/jmp/linux-2.6] / drivers / w1 / w1.c
index d640c1e..f3be299 100644 (file)
 #include <linux/device.h>
 #include <linux/slab.h>
 #include <linux/sched.h>
+#include <linux/kthread.h>
+#include <linux/freezer.h>
 
 #include <asm/atomic.h>
 
 #include "w1.h"
-#include "w1_io.h"
 #include "w1_log.h"
 #include "w1_int.h"
 #include "w1_family.h"
@@ -45,21 +46,17 @@ MODULE_AUTHOR("Evgeniy Polyakov <johnpol@2ka.mipt.ru>");
 MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol.");
 
 static int w1_timeout = 10;
-static int w1_control_timeout = 1;
 int w1_max_slave_count = 10;
 int w1_max_slave_ttl = 10;
 
 module_param_named(timeout, w1_timeout, int, 0);
-module_param_named(control_timeout, w1_control_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);
+DEFINE_MUTEX(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_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn);
 
 static int w1_master_match(struct device *dev, struct device_driver *drv)
 {
@@ -76,8 +73,6 @@ static void w1_master_release(struct device *dev)
        struct w1_master *md = dev_to_w1_master(dev);
 
        dev_dbg(dev, "%s: Releasing %s.\n", __func__, md->name);
-
-       dev_fini_netlink(md);
        memset(md, 0, sizeof(struct w1_master) + sizeof(struct w1_bus_master));
        kfree(md);
 }
@@ -86,10 +81,10 @@ static void w1_slave_release(struct device *dev)
 {
        struct w1_slave *sl = dev_to_w1_slave(dev);
 
-       dev_dbg(dev, "%s: Releasing %s.\n", __func__, sl->name);
+       printk("%s: Releasing %s.\n", __func__, sl->name);
 
        while (atomic_read(&sl->refcnt)) {
-               dev_dbg(dev, "Waiting for %s to become free: refcnt=%d.\n",
+               printk("Waiting for %s to become free: refcnt=%d.\n",
                                sl->name, atomic_read(&sl->refcnt));
                if (msleep_interruptible(1000))
                        flush_signals(current);
@@ -108,11 +103,12 @@ static ssize_t w1_slave_read_name(struct device *dev, struct device_attribute *a
        return sprintf(buf, "%s\n", sl->name);
 }
 
-static ssize_t w1_slave_read_id(struct kobject *kobj, char *buf, loff_t off, size_t count)
+static ssize_t w1_slave_read_id(struct kobject *kobj,
+                               struct bin_attribute *bin_attr,
+                               char *buf, loff_t off, size_t count)
 {
        struct w1_slave *sl = kobj_to_w1_slave(kobj);
 
-       atomic_inc(&sl->refcnt);
        if (off > 8) {
                count = 0;
        } else {
@@ -121,7 +117,6 @@ static ssize_t w1_slave_read_id(struct kobject *kobj, char *buf, loff_t off, siz
 
                memcpy(buf, (u8 *)&sl->reg_num, count);
        }
-       atomic_dec(&sl->refcnt);
 
        return count;
 }
@@ -133,16 +128,74 @@ static struct bin_attribute w1_slave_attr_bin_id = {
       .attr = {
               .name = "id",
               .mode = S_IRUGO,
-              .owner = THIS_MODULE,
       },
       .size = 8,
       .read = w1_slave_read_id,
 };
 
 /* Default family */
-static struct w1_family w1_default_family;
 
-static int w1_uevent(struct device *dev, char **envp, int num_envp, char *buffer, int buffer_size);
+static ssize_t w1_default_write(struct kobject *kobj,
+                               struct bin_attribute *bin_attr,
+                               char *buf, loff_t off, size_t count)
+{
+       struct w1_slave *sl = kobj_to_w1_slave(kobj);
+
+       mutex_lock(&sl->master->mutex);
+       if (w1_reset_select_slave(sl)) {
+               count = 0;
+               goto out_up;
+       }
+
+       w1_write_block(sl->master, buf, count);
+
+out_up:
+       mutex_unlock(&sl->master->mutex);
+       return count;
+}
+
+static ssize_t w1_default_read(struct kobject *kobj,
+                              struct bin_attribute *bin_attr,
+                              char *buf, loff_t off, size_t count)
+{
+       struct w1_slave *sl = kobj_to_w1_slave(kobj);
+
+       mutex_lock(&sl->master->mutex);
+       w1_read_block(sl->master, buf, count);
+       mutex_unlock(&sl->master->mutex);
+       return count;
+}
+
+static struct bin_attribute w1_default_attr = {
+      .attr = {
+              .name = "rw",
+              .mode = S_IRUGO | S_IWUSR,
+      },
+      .size = PAGE_SIZE,
+      .read = w1_default_read,
+      .write = w1_default_write,
+};
+
+static int w1_default_add_slave(struct w1_slave *sl)
+{
+       return sysfs_create_bin_file(&sl->dev.kobj, &w1_default_attr);
+}
+
+static void w1_default_remove_slave(struct w1_slave *sl)
+{
+       sysfs_remove_bin_file(&sl->dev.kobj, &w1_default_attr);
+}
+
+static struct w1_family_ops w1_default_fops = {
+       .add_slave      = w1_default_add_slave,
+       .remove_slave   = w1_default_remove_slave,
+};
+
+static struct w1_family w1_default_family = {
+       .fops = &w1_default_fops,
+};
+
+static int w1_uevent(struct device *dev, struct kobj_uevent_env *env);
 
 static struct bus_type w1_bus_type = {
        .name = "w1",
@@ -184,12 +237,9 @@ static ssize_t w1_master_attribute_show_name(struct device *dev, struct device_a
        struct w1_master *md = dev_to_w1_master(dev);
        ssize_t count;
 
-       if (down_interruptible (&md->mutex))
-               return -EBUSY;
-
+       mutex_lock(&md->mutex);
        count = sprintf(buf, "%s\n", md->name);
-
-       up(&md->mutex);
+       mutex_unlock(&md->mutex);
 
        return count;
 }
@@ -198,14 +248,16 @@ static ssize_t w1_master_attribute_store_search(struct device * dev,
                                                struct device_attribute *attr,
                                                const char * buf, size_t count)
 {
+       long tmp;
        struct w1_master *md = dev_to_w1_master(dev);
 
-       if (down_interruptible (&md->mutex))
-               return -EBUSY;
-
-       md->search_count = simple_strtol(buf, NULL, 0);
+       if (strict_strtol(buf, 0, &tmp) == -EINVAL)
+               return -EINVAL;
 
-       up(&md->mutex);
+       mutex_lock(&md->mutex);
+       md->search_count = tmp;
+       mutex_unlock(&md->mutex);
+       wake_up_process(md->thread);
 
        return count;
 }
@@ -217,27 +269,53 @@ static ssize_t w1_master_attribute_show_search(struct device *dev,
        struct w1_master *md = dev_to_w1_master(dev);
        ssize_t count;
 
-       if (down_interruptible (&md->mutex))
-               return -EBUSY;
-
+       mutex_lock(&md->mutex);
        count = sprintf(buf, "%d\n", md->search_count);
+       mutex_unlock(&md->mutex);
 
-       up(&md->mutex);
+       return count;
+}
+
+static ssize_t w1_master_attribute_store_pullup(struct device *dev,
+                                               struct device_attribute *attr,
+                                               const char *buf, size_t count)
+{
+       long tmp;
+       struct w1_master *md = dev_to_w1_master(dev);
+
+       if (strict_strtol(buf, 0, &tmp) == -EINVAL)
+               return -EINVAL;
+
+       mutex_lock(&md->mutex);
+       md->enable_pullup = tmp;
+       mutex_unlock(&md->mutex);
+       wake_up_process(md->thread);
 
        return count;
 }
 
-static ssize_t w1_master_attribute_show_pointer(struct device *dev, struct device_attribute *attr, char *buf)
+static ssize_t w1_master_attribute_show_pullup(struct device *dev,
+                                              struct device_attribute *attr,
+                                              char *buf)
 {
        struct w1_master *md = dev_to_w1_master(dev);
        ssize_t count;
 
-       if (down_interruptible(&md->mutex))
-               return -EBUSY;
+       mutex_lock(&md->mutex);
+       count = sprintf(buf, "%d\n", md->enable_pullup);
+       mutex_unlock(&md->mutex);
 
-       count = sprintf(buf, "0x%p\n", md->bus_master);
+       return count;
+}
+
+static ssize_t w1_master_attribute_show_pointer(struct device *dev, struct device_attribute *attr, char *buf)
+{
+       struct w1_master *md = dev_to_w1_master(dev);
+       ssize_t count;
 
-       up(&md->mutex);
+       mutex_lock(&md->mutex);
+       count = sprintf(buf, "0x%p\n", md->bus_master);
+       mutex_unlock(&md->mutex);
        return count;
 }
 
@@ -253,12 +331,9 @@ static ssize_t w1_master_attribute_show_max_slave_count(struct device *dev, stru
        struct w1_master *md = dev_to_w1_master(dev);
        ssize_t count;
 
-       if (down_interruptible(&md->mutex))
-               return -EBUSY;
-
+       mutex_lock(&md->mutex);
        count = sprintf(buf, "%d\n", md->max_slave_count);
-
-       up(&md->mutex);
+       mutex_unlock(&md->mutex);
        return count;
 }
 
@@ -267,12 +342,9 @@ static ssize_t w1_master_attribute_show_attempts(struct device *dev, struct devi
        struct w1_master *md = dev_to_w1_master(dev);
        ssize_t count;
 
-       if (down_interruptible(&md->mutex))
-               return -EBUSY;
-
+       mutex_lock(&md->mutex);
        count = sprintf(buf, "%lu\n", md->attempts);
-
-       up(&md->mutex);
+       mutex_unlock(&md->mutex);
        return count;
 }
 
@@ -281,22 +353,19 @@ static ssize_t w1_master_attribute_show_slave_count(struct device *dev, struct d
        struct w1_master *md = dev_to_w1_master(dev);
        ssize_t count;
 
-       if (down_interruptible(&md->mutex))
-               return -EBUSY;
-
+       mutex_lock(&md->mutex);
        count = sprintf(buf, "%d\n", md->slave_count);
-
-       up(&md->mutex);
+       mutex_unlock(&md->mutex);
        return count;
 }
 
-static ssize_t w1_master_attribute_show_slaves(struct device *dev, struct device_attribute *attr, char *buf)
+static ssize_t w1_master_attribute_show_slaves(struct device *dev,
+       struct device_attribute *attr, char *buf)
 {
        struct w1_master *md = dev_to_w1_master(dev);
        int c = PAGE_SIZE;
 
-       if (down_interruptible(&md->mutex))
-               return -EBUSY;
+       mutex_lock(&md->mutex);
 
        if (md->slave_count == 0)
                c -= snprintf(buf + PAGE_SIZE - c, c, "not found.\n");
@@ -311,11 +380,140 @@ static ssize_t w1_master_attribute_show_slaves(struct device *dev, struct device
                }
        }
 
-       up(&md->mutex);
+       mutex_unlock(&md->mutex);
 
        return PAGE_SIZE - c;
 }
 
+static ssize_t w1_master_attribute_show_add(struct device *dev,
+       struct device_attribute *attr, char *buf)
+{
+       int c = PAGE_SIZE;
+       c -= snprintf(buf+PAGE_SIZE - c, c,
+               "write device id xx-xxxxxxxxxxxx to add slave\n");
+       return PAGE_SIZE - c;
+}
+
+static int w1_atoreg_num(struct device *dev, const char *buf, size_t count,
+       struct w1_reg_num *rn)
+{
+       unsigned int family;
+       unsigned long long id;
+       int i;
+       u64 rn64_le;
+
+       /* The CRC value isn't read from the user because the sysfs directory
+        * doesn't include it and most messages from the bus search don't
+        * print it either.  It would be unreasonable for the user to then
+        * provide it.
+        */
+       const char *error_msg = "bad slave string format, expecting "
+               "ff-dddddddddddd\n";
+
+       if (buf[2] != '-') {
+               dev_err(dev, "%s", error_msg);
+               return -EINVAL;
+       }
+       i = sscanf(buf, "%02x-%012llx", &family, &id);
+       if (i != 2) {
+               dev_err(dev, "%s", error_msg);
+               return -EINVAL;
+       }
+       rn->family = family;
+       rn->id = id;
+
+       rn64_le = cpu_to_le64(*(u64 *)rn);
+       rn->crc = w1_calc_crc8((u8 *)&rn64_le, 7);
+
+#if 0
+       dev_info(dev, "With CRC device is %02x.%012llx.%02x.\n",
+                 rn->family, (unsigned long long)rn->id, rn->crc);
+#endif
+
+       return 0;
+}
+
+/* Searches the slaves in the w1_master and returns a pointer or NULL.
+ * Note: must hold the mutex
+ */
+static struct w1_slave *w1_slave_search_device(struct w1_master *dev,
+       struct w1_reg_num *rn)
+{
+       struct w1_slave *sl;
+       list_for_each_entry(sl, &dev->slist, w1_slave_entry) {
+               if (sl->reg_num.family == rn->family &&
+                               sl->reg_num.id == rn->id &&
+                               sl->reg_num.crc == rn->crc) {
+                       return sl;
+               }
+       }
+       return NULL;
+}
+
+static ssize_t w1_master_attribute_store_add(struct device *dev,
+                                               struct device_attribute *attr,
+                                               const char *buf, size_t count)
+{
+       struct w1_master *md = dev_to_w1_master(dev);
+       struct w1_reg_num rn;
+       struct w1_slave *sl;
+       ssize_t result = count;
+
+       if (w1_atoreg_num(dev, buf, count, &rn))
+               return -EINVAL;
+
+       mutex_lock(&md->mutex);
+       sl = w1_slave_search_device(md, &rn);
+       /* It would be nice to do a targeted search one the one-wire bus
+        * for the new device to see if it is out there or not.  But the
+        * current search doesn't support that.
+        */
+       if (sl) {
+               dev_info(dev, "Device %s already exists\n", sl->name);
+               result = -EINVAL;
+       } else {
+               w1_attach_slave_device(md, &rn);
+       }
+       mutex_unlock(&md->mutex);
+
+       return result;
+}
+
+static ssize_t w1_master_attribute_show_remove(struct device *dev,
+       struct device_attribute *attr, char *buf)
+{
+       int c = PAGE_SIZE;
+       c -= snprintf(buf+PAGE_SIZE - c, c,
+               "write device id xx-xxxxxxxxxxxx to remove slave\n");
+       return PAGE_SIZE - c;
+}
+
+static ssize_t w1_master_attribute_store_remove(struct device *dev,
+                                               struct device_attribute *attr,
+                                               const char *buf, size_t count)
+{
+       struct w1_master *md = dev_to_w1_master(dev);
+       struct w1_reg_num rn;
+       struct w1_slave *sl;
+       ssize_t result = count;
+
+       if (w1_atoreg_num(dev, buf, count, &rn))
+               return -EINVAL;
+
+       mutex_lock(&md->mutex);
+       sl = w1_slave_search_device(md, &rn);
+       if (sl) {
+               w1_slave_detach(sl);
+       } else {
+               dev_info(dev, "Device %02x-%012llx doesn't exists\n", rn.family,
+                       (unsigned long long)rn.id);
+               result = -EINVAL;
+       }
+       mutex_unlock(&md->mutex);
+
+       return result;
+}
+
 #define W1_MASTER_ATTR_RO(_name, _mode)                                \
        struct device_attribute w1_master_attribute_##_name =   \
                __ATTR(w1_master_##_name, _mode,                \
@@ -335,6 +533,9 @@ static W1_MASTER_ATTR_RO(attempts, S_IRUGO);
 static W1_MASTER_ATTR_RO(timeout, S_IRUGO);
 static W1_MASTER_ATTR_RO(pointer, S_IRUGO);
 static W1_MASTER_ATTR_RW(search, S_IRUGO | S_IWUGO);
+static W1_MASTER_ATTR_RW(pullup, S_IRUGO | S_IWUGO);
+static W1_MASTER_ATTR_RW(add, S_IRUGO | S_IWUGO);
+static W1_MASTER_ATTR_RW(remove, S_IRUGO | S_IWUGO);
 
 static struct attribute *w1_master_default_attrs[] = {
        &w1_master_attribute_name.attr,
@@ -345,6 +546,9 @@ static struct attribute *w1_master_default_attrs[] = {
        &w1_master_attribute_timeout.attr,
        &w1_master_attribute_pointer.attr,
        &w1_master_attribute_search.attr,
+       &w1_master_attribute_pullup.attr,
+       &w1_master_attribute_add.attr,
+       &w1_master_attribute_remove.attr,
        NULL
 };
 
@@ -357,18 +561,18 @@ int w1_create_master_attributes(struct w1_master *master)
        return sysfs_create_group(&master->dev.kobj, &w1_master_defattr_group);
 }
 
-static void w1_destroy_master_attributes(struct w1_master *master)
+void w1_destroy_master_attributes(struct w1_master *master)
 {
        sysfs_remove_group(&master->dev.kobj, &w1_master_defattr_group);
 }
 
 #ifdef CONFIG_HOTPLUG
-static int w1_uevent(struct device *dev, char **envp, int num_envp, char *buffer, int buffer_size)
+static int w1_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
        struct w1_master *md = NULL;
        struct w1_slave *sl = NULL;
        char *event_owner, *name;
-       int err, cur_index=0, cur_len=0;
+       int err;
 
        if (dev->driver == &w1_master_driver) {
                md = container_of(dev, struct w1_master, dev);
@@ -383,26 +587,25 @@ static int w1_uevent(struct device *dev, char **envp, int num_envp, char *buffer
                return -EINVAL;
        }
 
-       dev_dbg(dev, "Hotplug event for %s %s, bus_id=%s.\n", event_owner, name, dev->bus_id);
+       dev_dbg(dev, "Hotplug event for %s %s, bus_id=%s.\n",
+                       event_owner, name, dev->bus_id);
 
        if (dev->driver != &w1_slave_driver || !sl)
                return 0;
 
-       err = add_uevent_var(envp, num_envp, &cur_index, buffer, buffer_size,
-                       &cur_len, "W1_FID=%02X", sl->reg_num.family);
+       err = add_uevent_var(env, "W1_FID=%02X", sl->reg_num.family);
        if (err)
                return err;
 
-       err = add_uevent_var(envp, num_envp, &cur_index, buffer, buffer_size,
-                       &cur_len, "W1_SLAVE_ID=%024LX",
-                       (unsigned long long)sl->reg_num.id);
+       err = add_uevent_var(env, "W1_SLAVE_ID=%024LX",
+                            (unsigned long long)sl->reg_num.id);
        if (err)
                return err;
 
        return 0;
 };
 #else
-static int w1_uevent(struct device *dev, char **envp, int num_envp, char *buffer, int buffer_size)
+static int w1_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
        return 0;
 }
@@ -426,7 +629,8 @@ static int __w1_attach_slave_device(struct w1_slave *sl)
                 (unsigned int) sl->reg_num.family,
                 (unsigned long long) sl->reg_num.id);
 
-       dev_dbg(&sl->dev, "%s: registering %s as %p.\n", __func__, &sl->dev.bus_id[0]);
+       dev_dbg(&sl->dev, "%s: registering %s as %p.\n", __func__,
+               &sl->dev.bus_id[0], sl);
 
        err = device_register(&sl->dev);
        if (err < 0) {
@@ -483,7 +687,7 @@ static int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
        int err;
        struct w1_netlink_msg msg;
 
-       sl = kmalloc(sizeof(struct w1_slave), GFP_KERNEL);
+       sl = kzalloc(sizeof(struct w1_slave), GFP_KERNEL);
        if (!sl) {
                dev_err(&dev->dev,
                         "%s: failed to allocate new slave device.\n",
@@ -491,12 +695,12 @@ static int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
                return -ENOMEM;
        }
 
-       memset(sl, 0, sizeof(*sl));
 
        sl->owner = THIS_MODULE;
        sl->master = dev;
        set_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags);
 
+       memset(&msg, 0, sizeof(msg));
        memcpy(&sl->reg_num, rn, sizeof(sl->reg_num));
        atomic_set(&sl->refcnt, 0);
        init_completion(&sl->released);
@@ -527,14 +731,14 @@ static int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
        sl->ttl = dev->slave_ttl;
        dev->slave_count++;
 
-       memcpy(&msg.id.id, rn, sizeof(msg.id.id));
+       memcpy(msg.id.id, rn, sizeof(msg.id));
        msg.type = W1_SLAVE_ADD;
        w1_netlink_send(dev, &msg);
 
        return 0;
 }
 
-static void w1_slave_detach(struct w1_slave *sl)
+void w1_slave_detach(struct w1_slave *sl)
 {
        struct w1_netlink_msg msg;
 
@@ -545,7 +749,8 @@ static void w1_slave_detach(struct w1_slave *sl)
        if (sl->family->fops && sl->family->fops->remove_slave)
                sl->family->fops->remove_slave(sl);
 
-       memcpy(&msg.id.id, &sl->reg_num, sizeof(msg.id.id));
+       memset(&msg, 0, sizeof(msg));
+       memcpy(msg.id.id, &sl->reg_num, sizeof(msg.id));
        msg.type = W1_SLAVE_REMOVE;
        w1_netlink_send(sl->master, &msg);
 
@@ -557,53 +762,96 @@ static void w1_slave_detach(struct w1_slave *sl)
        kfree(sl);
 }
 
-static struct w1_master *w1_search_master(void *data)
+struct w1_master *w1_search_master_id(u32 id)
 {
        struct w1_master *dev;
        int found = 0;
 
-       spin_lock_bh(&w1_mlock);
+       mutex_lock(&w1_mlock);
        list_for_each_entry(dev, &w1_masters, w1_master_entry) {
-               if (dev->bus_master->data == data) {
+               if (dev->id == id) {
                        found = 1;
                        atomic_inc(&dev->refcnt);
                        break;
                }
        }
-       spin_unlock_bh(&w1_mlock);
+       mutex_unlock(&w1_mlock);
 
        return (found)?dev:NULL;
 }
 
-void w1_reconnect_slaves(struct w1_family *f)
+struct w1_slave *w1_search_slave(struct w1_reg_num *id)
+{
+       struct w1_master *dev;
+       struct w1_slave *sl = NULL;
+       int found = 0;
+
+       mutex_lock(&w1_mlock);
+       list_for_each_entry(dev, &w1_masters, w1_master_entry) {
+               mutex_lock(&dev->mutex);
+               list_for_each_entry(sl, &dev->slist, w1_slave_entry) {
+                       if (sl->reg_num.family == id->family &&
+                                       sl->reg_num.id == id->id &&
+                                       sl->reg_num.crc == id->crc) {
+                               found = 1;
+                               atomic_inc(&dev->refcnt);
+                               atomic_inc(&sl->refcnt);
+                               break;
+                       }
+               }
+               mutex_unlock(&dev->mutex);
+
+               if (found)
+                       break;
+       }
+       mutex_unlock(&w1_mlock);
+
+       return (found)?sl:NULL;
+}
+
+void w1_reconnect_slaves(struct w1_family *f, int attach)
 {
+       struct w1_slave *sl, *sln;
        struct w1_master *dev;
 
-       spin_lock_bh(&w1_mlock);
+       mutex_lock(&w1_mlock);
        list_for_each_entry(dev, &w1_masters, w1_master_entry) {
-               dev_dbg(&dev->dev, "Reconnecting slaves in %s into new family %02x.\n",
-                               dev->name, f->fid);
-               set_bit(W1_MASTER_NEED_RECONNECT, &dev->flags);
+               dev_dbg(&dev->dev, "Reconnecting slaves in device %s "
+                       "for family %02x.\n", dev->name, f->fid);
+               mutex_lock(&dev->mutex);
+               list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) {
+                       /* If it is a new family, slaves with the default
+                        * family driver and are that family will be
+                        * connected.  If the family is going away, devices
+                        * matching that family are reconneced.
+                        */
+                       if ((attach && sl->family->fid == W1_FAMILY_DEFAULT
+                               && sl->reg_num.family == f->fid) ||
+                               (!attach && sl->family->fid == f->fid)) {
+                               struct w1_reg_num rn;
+
+                               memcpy(&rn, &sl->reg_num, sizeof(rn));
+                               w1_slave_detach(sl);
+
+                               w1_attach_slave_device(dev, &rn);
+                       }
+               }
+               dev_dbg(&dev->dev, "Reconnecting slaves in device %s "
+                       "has been finished.\n", dev->name);
+               mutex_unlock(&dev->mutex);
        }
-       spin_unlock_bh(&w1_mlock);
+       mutex_unlock(&w1_mlock);
 }
 
-static void w1_slave_found(void *data, u64 rn)
+static void w1_slave_found(struct w1_master *dev, 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;
        u64 rn_le = cpu_to_le64(rn);
 
-       dev = w1_search_master(data);
-       if (!dev) {
-               printk(KERN_ERR "Failed to find w1 master device for data %p, "
-                      "it is impossible.\n", data);
-               return;
-       }
+       atomic_inc(&dev->refcnt);
 
        tmp = (struct w1_reg_num *) &rn;
 
@@ -617,9 +865,6 @@ static void w1_slave_found(void *data, u64 rn)
                    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++;
@@ -647,7 +892,7 @@ static void w1_slave_found(void *data, u64 rn)
  * @dev        The master device to search
  * @cb         Function to call when a device is found
  */
-void w1_search(struct w1_master *dev, w1_slave_found_callback cb)
+void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb)
 {
        u64 last_rn, rn, tmp64;
        int i, slave_count = 0;
@@ -678,7 +923,7 @@ void w1_search(struct w1_master *dev, w1_slave_found_callback cb)
                }
 
                /* Start the search */
-               w1_write_8(dev, W1_SEARCH);
+               w1_write_8(dev, search_type);
                for (i = 0; i < 64; ++i) {
                        /* Determine the direction/search bit */
                        if (i == desc_bit)
@@ -702,145 +947,71 @@ void w1_search(struct w1_master *dev, w1_slave_found_callback cb)
                        /* extract the direction taken & update the device number */
                        tmp64 = (triplet_ret >> 2);
                        rn |= (tmp64 << i);
+
+                       if (kthread_should_stop()) {
+                               printk(KERN_INFO "Abort w1_search (exiting)\n");
+                               return;
+                       }
                }
 
                if ( (triplet_ret & 0x03) != 0x03 ) {
                        if ( (desc_bit == last_zero) || (last_zero < 0))
                                last_device = 1;
                        desc_bit = last_zero;
-                       cb(dev->bus_master->data, rn);
+                       cb(dev, rn);
                }
        }
 }
 
-static int w1_control(void *data)
+void w1_search_process(struct w1_master *dev, u8 search_type)
 {
        struct w1_slave *sl, *sln;
-       struct w1_master *dev, *n;
-       int err, have_to_wait = 0;
-
-       daemonize("w1_control");
-       allow_signal(SIGTERM);
 
-       while (!control_needs_exit || have_to_wait) {
-               have_to_wait = 0;
+       list_for_each_entry(sl, &dev->slist, w1_slave_entry)
+               clear_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags);
 
-               try_to_freeze();
-               msleep_interruptible(w1_control_timeout * 1000);
+       w1_search_devices(dev, search_type, w1_slave_found);
 
-               if (signal_pending(current))
-                       flush_signals(current);
-
-               list_for_each_entry_safe(dev, n, &w1_masters, w1_master_entry) {
-                       if (!control_needs_exit && !dev->flags)
-                               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;
-                       }
-
-                       if (control_needs_exit) {
-                               set_bit(W1_MASTER_NEED_EXIT, &dev->flags);
-
-                               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);
-                       }
-
-                       if (test_bit(W1_MASTER_NEED_EXIT, &dev->flags)) {
-                               wait_for_completion(&dev->dev_exited);
-                               spin_lock_bh(&w1_mlock);
-                               list_del(&dev->w1_master_entry);
-                               spin_unlock_bh(&w1_mlock);
-
-                               down(&dev->mutex);
-                               list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) {
-                                       w1_slave_detach(sl);
-                               }
-                               w1_destroy_master_attributes(dev);
-                               up(&dev->mutex);
-                               atomic_dec(&dev->refcnt);
-                               continue;
-                       }
-
-                       if (test_bit(W1_MASTER_NEED_RECONNECT, &dev->flags)) {
-                               dev_dbg(&dev->dev, "Reconnecting slaves in device %s.\n", dev->name);
-                               down(&dev->mutex);
-                               list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) {
-                                       if (sl->family->fid == W1_FAMILY_DEFAULT) {
-                                               struct w1_reg_num rn;
-
-                                               memcpy(&rn, &sl->reg_num, sizeof(rn));
-                                               w1_slave_detach(sl);
-
-                                               w1_attach_slave_device(dev, &rn);
-                                       }
-                               }
-                               dev_dbg(&dev->dev, "Reconnecting slaves in device %s has been finished.\n", dev->name);
-                               clear_bit(W1_MASTER_NEED_RECONNECT, &dev->flags);
-                               up(&dev->mutex);
-                       }
-               }
+       list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) {
+               if (!test_bit(W1_SLAVE_ACTIVE, (unsigned long *)&sl->flags) && !--sl->ttl)
+                       w1_slave_detach(sl);
+               else if (test_bit(W1_SLAVE_ACTIVE, (unsigned long *)&sl->flags))
+                       sl->ttl = dev->slave_ttl;
        }
 
-       complete_and_exit(&w1_control_complete, 0);
+       if (dev->search_count > 0)
+               dev->search_count--;
 }
 
 int w1_process(void *data)
 {
        struct w1_master *dev = (struct w1_master *) data;
-       struct w1_slave *sl, *sln;
-
-       daemonize("%s", dev->name);
-       allow_signal(SIGTERM);
+       /* As long as w1_timeout is only set by a module parameter the sleep
+        * time can be calculated in jiffies once.
+        */
+       const unsigned long jtime = msecs_to_jiffies(w1_timeout * 1000);
+
+       while (!kthread_should_stop()) {
+               if (dev->search_count) {
+                       mutex_lock(&dev->mutex);
+                       w1_search_process(dev, W1_SEARCH);
+                       mutex_unlock(&dev->mutex);
+               }
 
-       while (!test_bit(W1_MASTER_NEED_EXIT, &dev->flags)) {
                try_to_freeze();
-               msleep_interruptible(w1_timeout * 1000);
-
-               if (signal_pending(current))
-                       flush_signals(current);
+               __set_current_state(TASK_INTERRUPTIBLE);
 
-               if (test_bit(W1_MASTER_NEED_EXIT, &dev->flags))
+               if (kthread_should_stop())
                        break;
 
-               if (!dev->initialized)
-                       continue;
-
-               if (dev->search_count == 0)
-                       continue;
-
-               if (down_interruptible(&dev->mutex))
-                       continue;
-
-               list_for_each_entry(sl, &dev->slist, w1_slave_entry)
-                       clear_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags);
-
-               w1_search_devices(dev, w1_slave_found);
-
-               list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) {
-                       if (!test_bit(W1_SLAVE_ACTIVE, (unsigned long *)&sl->flags) && !--sl->ttl) {
-                               w1_slave_detach(sl);
-
-                               dev->slave_count--;
-                       } else if (test_bit(W1_SLAVE_ACTIVE, (unsigned long *)&sl->flags))
-                               sl->ttl = dev->slave_ttl;
-               }
-
-               if (dev->search_count > 0)
-                       dev->search_count--;
-
-               up(&dev->mutex);
+               /* Only sleep when the search is active. */
+               if (dev->search_count)
+                       schedule_timeout(jtime);
+               else
+                       schedule();
        }
 
        atomic_dec(&dev->refcnt);
-       complete_and_exit(&dev->dev_exited, 0);
 
        return 0;
 }
@@ -851,6 +1022,8 @@ static int w1_init(void)
 
        printk(KERN_INFO "Driver for 1-wire Dallas network protocol.\n");
 
+       w1_init_netlink();
+
        retval = bus_register(&w1_bus_type);
        if (retval) {
                printk(KERN_ERR "Failed to register bus. err=%d.\n", retval);
@@ -873,18 +1046,13 @@ static int w1_init(void)
                goto err_out_master_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_slave_unregister;
-       }
-
        return 0;
 
+#if 0
+/* For undoing the slave register if there was a step after it. */
 err_out_slave_unregister:
        driver_unregister(&w1_slave_driver);
+#endif
 
 err_out_master_unregister:
        driver_unregister(&w1_master_driver);
@@ -900,11 +1068,11 @@ static void w1_fini(void)
 {
        struct w1_master *dev;
 
+       /* Set netlink removal messages and some cleanup */
        list_for_each_entry(dev, &w1_masters, w1_master_entry)
                __w1_remove_master_device(dev);
 
-       control_needs_exit = 1;
-       wait_for_completion(&w1_control_complete);
+       w1_fini_netlink();
 
        driver_unregister(&w1_slave_driver);
        driver_unregister(&w1_master_driver);