Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/w1-2.6

Documentation/w1/w1.generic

···
-Any w1 device must be connected to w1 bus master device - for example
-ds9490 usb device or w1-over-GPIO or RS232 converter.
-Driver for w1 bus master must provide several functions(you can find
-them in struct w1_bus_master definition in w1.h) which then will be
-called by w1 core to send various commands over w1 bus(by default it is
-reset and search commands). When some device is found on the bus, w1 core
-checks if driver for it's family is loaded.
-If driver is loaded w1 core creates new w1_slave object and registers it
-in the system(creates some generic sysfs files(struct w1_family_ops in
-w1_family.h), notifies any registered listener and so on...).
-It is device driver's business to provide any communication method
-upstream.
-For example w1_therm driver(ds18?20 thermal sensor family driver)
-provides temperature reading function which is bound to ->rbin() method
-of the above w1_family_ops structure.
-w1_smem - driver for simple 64bit memory cell provides ID reading
-method.
+The 1-wire (w1) subsystem
+------------------------------------------------------------------
+The 1-wire bus is a simple master-slave bus that communicates via a single
+signal wire (plus ground, so two wires).
+
+Devices communicate on the bus by pulling the signal to ground via an open
+drain output and by sampling the logic level of the signal line.
+
+The w1 subsystem provides the framework for managing w1 masters and
+communication with slaves.
+
+All w1 slave devices must be connected to a w1 bus master device.
+
+Example w1 master devices:
+    DS9490 usb device
+    W1-over-GPIO
+    DS2482 (i2c to w1 bridge)
+    Emulated devices, such as a RS232 converter, parallel port adapter, etc
+
+
+What does the w1 subsystem do?
+------------------------------------------------------------------
+When a w1 master driver registers with the w1 subsystem, the following occurs:
+
+ - sysfs entries for that w1 master are created
+ - the w1 bus is periodically searched for new slave devices
+
+When a device is found on the bus, w1 core checks if driver for it's family is
+loaded. If so, the family driver is attached to the slave.
+If there is no driver for the family, a simple sysfs entry is created
+for the slave device.
+
+
+W1 device families
+------------------------------------------------------------------
+Slave devices are handled by a driver written for a family of w1 devices.
+
+A family driver populates a struct w1_family_ops (see w1_family.h) and
+registers with the w1 subsystem.
+
+Current family drivers:
+w1_therm - (ds18?20 thermal sensor family driver)
+    provides temperature reading function which is bound to ->rbin() method
+    of the above w1_family_ops structure.
+
+w1_smem - driver for simple 64bit memory cell provides ID reading method.
 
 You can call above methods by reading appropriate sysfs files.
+
+
+What does a w1 master driver need to implement?
+------------------------------------------------------------------
+
+The driver for w1 bus master must provide at minimum two functions.
+
+Emulated devices must provide the ability to set the output signal level
+(write_bit) and sample the signal level (read_bit).
+
+Devices that support the 1-wire natively must provide the ability to write and
+sample a bit (touch_bit) and reset the bus (reset_bus).
+
+Most hardware provides higher-level functions that offload w1 handling.
+See struct w1_bus_master definition in w1.h for details.
+
+
+w1 master sysfs interface
+------------------------------------------------------------------
+<xx-xxxxxxxxxxxxx> - a directory for a found device. The format is family-serial
+bus                - (standard) symlink to the w1 bus
+driver             - (standard) symlink to the w1 driver
+w1_master_attempts - the number of times a search was attempted
+w1_master_max_slave_count
+                   - the maximum slaves that may be attached to a master
+w1_master_name     - the name of the device (w1_bus_masterX)
+w1_master_search   - the number of searches left to do, -1=continual (default)
+w1_master_slave_count
+                   - the number of slaves found
+w1_master_slaves   - the names of the slaves, one per line
+w1_master_timeout  - the delay in seconds between searches
+
+If you have a w1 bus that never changes (you don't add or remove devices),
+you can set w1_master_search to a positive value to disable searches.
+
+
+w1 slave sysfs interface
+------------------------------------------------------------------
+bus                - (standard) symlink to the w1 bus
+driver             - (standard) symlink to the w1 driver
+name               - the device name, usually the same as the directory name
+w1_slave           - (optional) a binary file whose meaning depends on the
+                     family driver
+

drivers/w1/Kconfig

···
 config W1
 	tristate "Dallas's 1-wire support"
 	---help---
-	  Dallas's 1-wire bus is usefull to connect slow 1-pin devices 
+	  Dallas's 1-wire bus is usefull to connect slow 1-pin devices
 	  such as iButtons and thermal sensors.
-	  
+
 	  If you want W1 support, you should say Y here.
 
 	  This W1 support can also be built as a module.  If so, the module
···
 	help
 	  Say Y here if you want to communicate with your 1-wire devices
 	  using Matrox's G400 GPIO pins.
-	  
-	  This support is also available as a module.  If so, the module 
+
+	  This support is also available as a module.  If so, the module
 	  will be called matrox_w1.ko.
 
 config W1_DS9490
···
 	help
 	  Say Y here if you want to have a driver for DS9490R UWB <-> W1 bridge.
 
-	  This support is also available as a module.  If so, the module 
+	  This support is also available as a module.  If so, the module
 	  will be called ds9490r.ko.
 
-config W1_DS9490_BRIDGE
+config W1_DS9490R_BRIDGE
 	tristate "DS9490R USB <-> W1 transport layer for 1-wire"
 	depends on W1_DS9490
 	help
 	  Say Y here if you want to communicate with your 1-wire devices
 	  using DS9490R USB bridge.
 
-	  This support is also available as a module.  If so, the module 
+	  This support is also available as a module.  If so, the module
 	  will be called ds_w1_bridge.ko.
 
 config W1_THERM
···
 	tristate "Simple 64bit memory family implementation"
 	depends on W1
 	help
-	  Say Y here if you want to connect 1-wire 
+	  Say Y here if you want to connect 1-wire
 	  simple 64bit memory rom(ds2401/ds2411/ds1990*) to you wire.
 
 endmenu

drivers/w1/ds_w1_bridge.c

···
 	return byte;
 }
 
-static void ds9490r_write_block(unsigned long data, u8 *buf, int len)
+static void ds9490r_write_block(unsigned long data, const u8 *buf, int len)
 {
 	struct ds_device *dev = (struct ds_device *)data;
 
-	ds_write_block(dev, buf, len);
+	ds_write_block(dev, (u8 *)buf, len);
 }
 
 static u8 ds9490r_read_block(unsigned long data, u8 *buf, int len)

drivers/w1/matrox_w1.c

···
 /*
- * 	matrox_w1.c
+ *	matrox_w1.c
  *
  * Copyright (c) 2004 Evgeniy Polyakov <[e-mail]>
- * 
+ *
  *
  * 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
···
 	.remove = __devexit_p(matrox_w1_remove),
 };
 
-/* 
+/*
  * Matrox G400 DDC registers.
  */
 
···
 
 	dev->bus_master = (struct w1_bus_master *)(dev + 1);
 
-	/* 
-	 * True for G400, for some other we need resource 0, see drivers/video/matrox/matroxfb_base.c 
+	/*
+	 * True for G400, for some other we need resource 0, see drivers/video/matrox/matroxfb_base.c
 	 */
 
 	dev->phys_addr = pci_resource_start(pdev, 1);

drivers/w1/w1.c

···
 /*
- * 	w1.c
+ *	w1.c
  *
  * Copyright (c) 2004 Evgeniy Polyakov <[e-mail]>
- * 
+ *
  *
  * 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
···
 static int control_needs_exit;
 static DECLARE_COMPLETION(w1_control_complete);
 
+/* stuff for the default family */
+static ssize_t w1_famdefault_read_name(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
+	return(sprintf(buf, "%s\n", sl->name));
+}
+static struct w1_family_ops w1_default_fops = {
+	.rname = &w1_famdefault_read_name,
+};
+static struct w1_family w1_default_family = {
+	.fops = &w1_default_fops,
+};
+
 static int w1_master_match(struct device *dev, struct device_driver *drv)
 {
 	return 1;
···
 	return sprintf(buf, "No family registered.\n");
 }
 
+static struct device_attribute w1_slave_attribute =
+	__ATTR(name, S_IRUGO, w1_default_read_name, NULL);
+
+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 struct bus_type w1_bus_type = {
 	.name = "w1",
 	.match = w1_master_match,
···
 	.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, struct device_attribute *attr, char *buf)
 {
-	struct w1_master *md = container_of (dev, struct w1_master, dev);
+	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_store_search(struct device * dev,
+						struct device_attribute *attr,
+						const char * buf, size_t count)
+{
+	struct w1_master *md = container_of(dev, struct w1_master, dev);
+
+	if (down_interruptible (&md->mutex))
+		return -EBUSY;
+
+	md->search_count = simple_strtol(buf, NULL, 0);
+
+	up(&md->mutex);
+
+	return count;
+}
+
+static ssize_t w1_master_attribute_show_search(struct device *dev,
+					       struct device_attribute *attr,
+					       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->search_count);
+
 	up(&md->mutex);
 
 	return count;
···
 {
 	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;
 }
···
 {
 	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;
 }
···
 {
 	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;
 }
···
 {
 	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, struct device_attribute *attr, char *buf)
-
 {
 	struct w1_master *md = container_of(dev, struct w1_master, dev);
 	int c = PAGE_SIZE;
···
 		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);
+			c -= snprintf(buf + PAGE_SIZE - c, c, "%s\n", sl->name);
 		}
 	}
 
···
 	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,
+#define W1_MASTER_ATTR_RO(_name, _mode)				\
+	struct device_attribute w1_master_attribute_##_name =	\
+		__ATTR(w1_master_##_name, _mode,		\
+		       w1_master_attribute_show_##_name, NULL)
+
+#define W1_MASTER_ATTR_RW(_name, _mode)				\
+	struct device_attribute w1_master_attribute_##_name =	\
+		__ATTR(w1_master_##_name, _mode,		\
+		       w1_master_attribute_show_##_name,	\
+		       w1_master_attribute_store_##_name)
+
+static W1_MASTER_ATTR_RO(name, S_IRUGO);
+static W1_MASTER_ATTR_RO(slaves, S_IRUGO);
+static W1_MASTER_ATTR_RO(slave_count, S_IRUGO);
+static W1_MASTER_ATTR_RO(max_slave_count, S_IRUGO);
+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 struct attribute *w1_master_default_attrs[] = {
+	&w1_master_attribute_name.attr,
+	&w1_master_attribute_slaves.attr,
+	&w1_master_attribute_slave_count.attr,
+	&w1_master_attribute_max_slave_count.attr,
+	&w1_master_attribute_attempts.attr,
+	&w1_master_attribute_timeout.attr,
+	&w1_master_attribute_pointer.attr,
+	&w1_master_attribute_search.attr,
+	NULL
 };
 
-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 struct attribute_group w1_master_defattr_group = {
+	.attrs = w1_master_default_attrs,
 };
+
+int w1_create_master_attributes(struct w1_master *master)
+{
+	return sysfs_create_group(&master->dev.kobj, &w1_master_defattr_group);
+}
+
+void w1_destroy_master_attributes(struct w1_master *master)
+{
+	sysfs_remove_group(&master->dev.kobj, &w1_master_defattr_group);
+}
 
 static int __w1_attach_slave_device(struct w1_slave *sl)
 {
···
 	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);
+		 "%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);
+			"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);
+			"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;
+	if ( sl->attr_bin.read ) {
+		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_unregister(&sl->dev);
+			return err;
+		}
 	}
 
 	list_add_tail(&sl->w1_slave_entry, &sl->master->slist);
···
 	spin_lock(&w1_flock);
 	f = w1_family_registered(rn->family);
 	if (!f) {
-		spin_unlock(&w1_flock);
+		f= &w1_default_family;
 		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);
···
 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)) {
···
 			flush_signals(current);
 	}
 
-	sysfs_remove_bin_file (&sl->dev.kobj, &sl->attr_bin);
+	if ( sl->attr_bin.read ) {
+		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);
+
+	sl->master->slave_count--;
 
 	memcpy(&msg.id.id, &sl->reg_num, sizeof(msg.id.id));
 	msg.type = W1_SLAVE_REMOVE;
···
 {
 	struct w1_master *dev;
 	int found = 0;
-	
-	spin_lock_irq(&w1_mlock);
+
+	spin_lock_bh(&w1_mlock);
 	list_for_each_entry(dev, &w1_masters, w1_master_entry) {
 		if (dev->bus_master->data == data) {
 			found = 1;
···
 			break;
 		}
 	}
-	spin_unlock_irq(&w1_mlock);
+	spin_unlock_bh(&w1_mlock);
 
 	return (found)?dev:NULL;
 }
 
-void w1_slave_found(unsigned long data, u64 rn)
+void w1_reconnect_slaves(struct w1_family *f)
+{
+	struct w1_master *dev;
+
+	spin_lock_bh(&w1_mlock);
+	list_for_each_entry(dev, &w1_masters, w1_master_entry) {
+		dev_info(&dev->dev, "Reconnecting slaves in %s into new family %02x.\n",
+				dev->name, f->fid);
+		set_bit(W1_MASTER_NEED_RECONNECT, &dev->flags);
+	}
+	spin_unlock_bh(&w1_mlock);
+}
+
+
+static void w1_slave_found(unsigned long data, u64 rn)
 {
 	int slave_count;
 	struct w1_slave *sl;
···
 				data);
 		return;
 	}
-	
+
 	tmp = (struct w1_reg_num *) &rn;
 
 	slave_count = 0;
···
 		    sl->reg_num.crc == tmp->crc) {
 			set_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags);
 			break;
-		}
-		else if (sl->reg_num.family == tmp->family) {
+		} else if (sl->reg_num.family == tmp->family) {
 			family_found = 1;
 			break;
 		}
···
 		rn && ((le64_to_cpu(rn) >> 56) & 0xff) == w1_calc_crc8((u8 *)&rn, 7)) {
 		w1_attach_slave_device(dev, tmp);
 	}
-			
+
 	atomic_dec(&dev->refcnt);
 }
 
-void w1_search(struct w1_master *dev)
+/**
+ * Performs a ROM Search & registers any devices found.
+ * The 1-wire search is a simple binary tree search.
+ * For each bit of the address, we read two bits and write one bit.
+ * The bit written will put to sleep all devies that don't match that bit.
+ * When the two reads differ, the direction choice is obvious.
+ * When both bits are 0, we must choose a path to take.
+ * When we can scan all 64 bits without having to choose a path, we are done.
+ *
+ * See "Application note 187 1-wire search algorithm" at www.maxim-ic.com
+ *
+ * @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)
 {
-	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;
+	u64 last_rn, rn, tmp64;
+	int i, slave_count = 0;
+	int last_zero, last_device;
+	int search_bit, desc_bit;
+	u8  triplet_ret = 0;
 
-	search_bit = id_bit = comp_bit = 0;
-	rn = tmp = last = 0;
-	last_device = last_zero = last_family_desc = 0;
+	search_bit = 0;
+	rn = last_rn = 0;
+	last_device = 0;
+	last_zero = -1;
 
 	desc_bit = 64;
 
-	while (!(id_bit && comp_bit) && !last_device
-		&& count++ < dev->max_slave_count) {
-		last = rn;
+	while ( !last_device && (slave_count++ < dev->max_slave_count) ) {
+		last_rn = rn;
 		rn = 0;
-
-		last_family_desc = 0;
 
 		/*
 		 * Reset bus and all 1-wire device state machines
···
 			break;
 		}
 
-#if 1
+		/* Start the search */
 		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);
+			/* Determine the direction/search bit */
+			if (i == desc_bit)
+				search_bit = 1;	  /* took the 0 path last time, so take the 1 path */
+			else if (i > desc_bit)
+				search_bit = 0;	  /* take the 0 path on the next branch */
+			else
+				search_bit = ((last_rn >> i) & 0x1);
 
-			if (id_bit && comp_bit)
+			/** Read two bits and write one bit */
+			triplet_ret = w1_triplet(dev, search_bit);
+
+			/* quit if no device responded */
+			if ( (triplet_ret & 0x03) == 0x03 )
 				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 both directions were valid, and we took the 0 path... */
+			if (triplet_ret == 0)
+				last_zero = i;
 
-				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);
-
+			/* extract the direction taken & update the device number */
+			tmp64 = (triplet_ret >> 2);
+			rn |= (tmp64 << i);
 		}
-#endif
 
-		if (desc_bit == last_zero)
-			last_device = 1;
-
-		desc_bit = last_zero;
-	
-		w1_slave_found(dev->bus_master->data, rn);
+		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);
+		}
 	}
 }
 
-int w1_create_master_attributes(struct w1_master *dev)
+static int w1_control(void *data)
 {
-	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;
+	struct w1_slave *sl, *sln;
+	struct w1_master *dev, *n;
 	int err, have_to_wait = 0;
 
 	daemonize("w1_control");
···
 		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)
+		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.
···
 				continue;
 			}
 
-			spin_lock(&w1_mlock);
-			list_del(&dev->w1_master_entry);
-			spin_unlock(&w1_mlock);
-
 			if (control_needs_exit) {
-				dev->need_exit = 1;
+				set_bit(W1_MASTER_NEED_EXIT, &dev->flags);
 
 				err = kill_proc(dev->kpid, SIGTERM, 1);
 				if (err)
···
 						 dev->kpid);
 			}
 
-			wait_for_completion(&dev->dev_exited);
+			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);
 
-			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_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) {
 					list_del(&sl->w1_slave_entry);
 
 					w1_slave_detach(sl);
 					kfree(sl);
 				}
+				w1_destroy_master_attributes(dev);
+				atomic_dec(&dev->refcnt);
+				continue;
 			}
-			w1_destroy_master_attributes(dev);
-			atomic_dec(&dev->refcnt);
+
+			if (test_bit(W1_MASTER_NEED_RECONNECT, &dev->flags)) {
+				dev_info(&dev->dev, "Reconnecting slaves in device %s.\n", dev->name);
+				down(&dev->mutex);
+				list_for_each_entry(sl, &dev->slist, w1_slave_entry) {
+					if (sl->family->fid == W1_FAMILY_DEFAULT) {
+						struct w1_reg_num rn;
+						list_del(&sl->w1_slave_entry);
+						w1_slave_detach(sl);
+
+						memcpy(&rn, &sl->reg_num, sizeof(rn));
+
+						kfree(sl);
+
+						w1_attach_slave_device(dev, &rn);
+					}
+				}
+				clear_bit(W1_MASTER_NEED_RECONNECT, &dev->flags);
+				up(&dev->mutex);
+			}
 		}
 	}
 
···
 int w1_process(void *data)
 {
 	struct w1_master *dev = (struct w1_master *) data;
-	struct list_head *ent, *n;
-	struct w1_slave *sl;
+	struct w1_slave *sl, *sln;
 
 	daemonize("%s", dev->name);
 	allow_signal(SIGTERM);
 
-	while (!dev->need_exit) {
+	while (!test_bit(W1_MASTER_NEED_EXIT, &dev->flags)) {
 		try_to_freeze(PF_FREEZE);
 		msleep_interruptible(w1_timeout * 1000);
 
 		if (signal_pending(current))
 			flush_signals(current);
 
-		if (dev->need_exit)
+		if (test_bit(W1_MASTER_NEED_EXIT, &dev->flags))
 			break;
 
 		if (!dev->initialized)
 			continue;
 
+		if (dev->search_count == 0)
+			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);
+		list_for_each_entry(sl, &dev->slist, w1_slave_entry)
+			clear_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags);
 
-			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_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) {
+			if (!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))
+			} 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);
 	}
 
···
 	return 0;
 }
 
-int w1_init(void)
+static int w1_init(void)
 {
 	int retval;
 
···
 	return retval;
 }
 
-void w1_fini(void)
+static 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);
+	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);
 
 	driver_unregister(&w1_driver);

drivers/w1/w1.h

···
 /*
- * 	w1.h
+ *	w1.h
  *
  * Copyright (c) 2004 Evgeniy Polyakov <[e-mail]>
- * 
+ *
  *
  * 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
···
 	int			ttl;
 
 	struct w1_master	*master;
-	struct w1_family 	*family;
-	struct device 		dev;
-	struct completion 	dev_released;
+	struct w1_family	*family;
+	struct device		dev;
+	struct completion	dev_released;
 
-	struct bin_attribute 	attr_bin;
-	struct device_attribute	attr_name, attr_val;
+	struct bin_attribute	attr_bin;
+	struct device_attribute	attr_name;
 };
 
 typedef void (* w1_slave_found_callback)(unsigned long, u64);
 
+
+/**
+ * Note: read_bit and write_bit are very low level functions and should only
+ * be used with hardware that doesn't really support 1-wire operations,
+ * like a parallel/serial port.
+ * Either define read_bit and write_bit OR define, at minimum, touch_bit and
+ * reset_bus.
+ */
 struct w1_bus_master
 {
-	unsigned long		data;
+	/** the first parameter in all the functions below */
+	unsigned long	data;
 
-	u8			(*read_bit)(unsigned long);
-	void			(*write_bit)(unsigned long, u8);
-  	
-	u8			(*read_byte)(unsigned long);
-  	void			(*write_byte)(unsigned long, u8);
-  	
-	u8			(*read_block)(unsigned long, u8 *, int);
-	void			(*write_block)(unsigned long, u8 *, int);
-	
-  	u8			(*touch_bit)(unsigned long, u8);
-  
-  	u8			(*reset_bus)(unsigned long);
+	/**
+	 * Sample the line level
+	 * @return the level read (0 or 1)
+	 */
+	u8		(*read_bit)(unsigned long);
 
-	void			(*search)(unsigned long, w1_slave_found_callback);
+	/** Sets the line level */
+	void		(*write_bit)(unsigned long, u8);
+
+	/**
+	 * touch_bit is the lowest-level function for devices that really
+	 * support the 1-wire protocol.
+	 * touch_bit(0) = write-0 cycle
+	 * touch_bit(1) = write-1 / read cycle
+	 * @return the bit read (0 or 1)
+	 */
+	u8		(*touch_bit)(unsigned long, u8);
+
+	/**
+	 * Reads a bytes. Same as 8 touch_bit(1) calls.
+	 * @return the byte read
+	 */
+	u8		(*read_byte)(unsigned long);
+
+	/**
+	 * Writes a byte. Same as 8 touch_bit(x) calls.
+	 */
+	void		(*write_byte)(unsigned long, u8);
+
+	/**
+	 * Same as a series of read_byte() calls
+	 * @return the number of bytes read
+	 */
+	u8		(*read_block)(unsigned long, u8 *, int);
+
+	/** Same as a series of write_byte() calls */
+	void		(*write_block)(unsigned long, const u8 *, int);
+
+	/**
+	 * Combines two reads and a smart write for ROM searches
+	 * @return bit0=Id bit1=comp_id bit2=dir_taken
+	 */
+	u8		(*triplet)(unsigned long, u8);
+
+	/**
+	 * long write-0 with a read for the presence pulse detection
+	 * @return -1=Error, 0=Device present, 1=No device present
+	 */
+	u8		(*reset_bus)(unsigned long);
+
+	/** Really nice hardware can handles the ROM searches */
+	void		(*search)(unsigned long, w1_slave_found_callback);
 };
+
+#define W1_MASTER_NEED_EXIT		0
+#define W1_MASTER_NEED_RECONNECT	1
 
 struct w1_master
 {
···
 	int			slave_ttl;
 	int			initialized;
 	u32			id;
+	int			search_count;
 
 	atomic_t		refcnt;
 
 	void			*priv;
 	int			priv_size;
 
-	int			need_exit;
+	long			flags;
+
 	pid_t			kpid;
-	struct semaphore 	mutex;
+	struct semaphore	mutex;
 
 	struct device_driver	*driver;
-	struct device 		dev;
-	struct completion 	dev_released;
-	struct completion 	dev_exited;
+	struct device		dev;
+	struct completion	dev_released;
+	struct completion	dev_exited;
 
 	struct w1_bus_master	*bus_master;
 
 	u32			seq, groups;
-	struct sock 		*nls;
+	struct sock		*nls;
 };
 
 int w1_create_master_attributes(struct w1_master *);
-void w1_destroy_master_attributes(struct w1_master *);
-void w1_search(struct w1_master *dev);
+void w1_search(struct w1_master *dev, w1_slave_found_callback cb);
 
 #endif /* __KERNEL__ */
 

drivers/w1/w1_family.c

···
 /*
- * 	w1_family.c
+ *	w1_family.c
  *
  * Copyright (c) 2004 Evgeniy Polyakov <[e-mail]>
- * 
+ *
  *
  * 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
···
 
 DEFINE_SPINLOCK(w1_flock);
 static LIST_HEAD(w1_families);
+extern void w1_reconnect_slaves(struct w1_family *f);
 
 static int w1_check_family(struct w1_family *f)
 {
-	if (!f->fops->rname || !f->fops->rbin || !f->fops->rval || !f->fops->rvalname)
+	if (!f->fops->rname || !f->fops->rbin)
 		return -EINVAL;
 
 	return 0;
···
 		newf->need_exit = 0;
 		list_add_tail(&newf->family_entry, &w1_families);
 	}
-
 	spin_unlock(&w1_flock);
+
+	w1_reconnect_slaves(newf);
 
 	return ret;
 }

drivers/w1/w1_family.h

···
 /*
- * 	w1_family.h
+ *	w1_family.h
  *
  * Copyright (c) 2004 Evgeniy Polyakov <[e-mail]>
- * 
+ *
  *
  * 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
···
 #include <asm/atomic.h>
 
 #define W1_FAMILY_DEFAULT	0
-#define W1_FAMILY_THERM		0x10
-#define W1_FAMILY_SMEM		0x01
+#define W1_FAMILY_SMEM_01	0x01
+#define W1_FAMILY_SMEM_81	0x81
+#define W1_THERM_DS18S20 	0x10
+#define W1_THERM_DS1822  	0x22
+#define W1_THERM_DS18B20 	0x28
 
 #define MAXNAMELEN		32
 
···
 {
 	ssize_t (* rname)(struct device *, struct device_attribute *, char *);
 	ssize_t (* rbin)(struct kobject *, char *, loff_t, size_t);
-	
-	ssize_t (* rval)(struct device *, struct device_attribute *, char *);
-	unsigned char rvalname[MAXNAMELEN];
 };
 
 struct w1_family
 {
 	struct list_head	family_entry;
 	u8			fid;
-	
+
 	struct w1_family_ops	*fops;
-	
+
 	atomic_t		refcnt;
 	u8			need_exit;
 };

drivers/w1/w1_int.c

···
 /*
- * 	w1_int.c
+ *	w1_int.c
  *
  * Copyright (c) 2004 Evgeniy Polyakov <[e-mail]>
- * 
+ *
  *
  * 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
···
 
 extern int w1_process(void *);
 
-struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl,
-	      struct device_driver *driver, struct device *device)
+static struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl,
+				       struct device_driver *driver,
+				       struct device *device)
 {
 	struct w1_master *dev;
 	int err;
···
 
 	dev->bus_master = (struct w1_bus_master *)(dev + 1);
 
-	dev->owner 		= THIS_MODULE;
-	dev->max_slave_count 	= slave_count;
-	dev->slave_count 	= 0;
-	dev->attempts 		= 0;
-	dev->kpid 		= -1;
-	dev->initialized 	= 0;
-	dev->id 		= id;
+	dev->owner		= THIS_MODULE;
+	dev->max_slave_count	= slave_count;
+	dev->slave_count	= 0;
+	dev->attempts		= 0;
+	dev->kpid		= -1;
+	dev->initialized	= 0;
+	dev->id			= id;
 	dev->slave_ttl		= slave_ttl;
+        dev->search_count	= -1; /* continual scan */
 
 	atomic_set(&dev->refcnt, 2);
 
···
 	return dev;
 }
 
-void w1_free_dev(struct w1_master *dev)
+static void w1_free_dev(struct w1_master *dev)
 {
 	device_unregister(&dev->dev);
 	if (dev->nls && dev->nls->sk_socket)
···
 	struct w1_master *dev;
 	int retval = 0;
 	struct w1_netlink_msg msg;
+
+        /* validate minimum functionality */
+        if (!(master->touch_bit && master->reset_bus) &&
+            !(master->write_bit && master->read_bit)) {
+		printk(KERN_ERR "w1_add_master_device: invalid function set\n");
+		return(-EINVAL);
+        }
 
 	dev = w1_alloc_dev(w1_ids++, w1_max_slave_count, w1_max_slave_ttl, &w1_driver, &w1_device);
 	if (!dev)
···
 	return 0;
 
 err_out_kill_thread:
-	dev->need_exit = 1;
+	set_bit(W1_MASTER_NEED_EXIT, &dev->flags);
 	if (kill_proc(dev->kpid, SIGTERM, 1))
 		dev_err(&dev->dev,
 			 "Failed to send signal to w1 kernel thread %d.\n",
···
 	int err;
 	struct w1_netlink_msg msg;
 
-	dev->need_exit = 1;
+	set_bit(W1_MASTER_NEED_EXIT, &dev->flags);
 	err = kill_proc(dev->kpid, SIGTERM, 1);
 	if (err)
 		dev_err(&dev->dev,
···
 void w1_remove_master_device(struct w1_bus_master *bm)
 {
 	struct w1_master *dev = NULL;
-	struct list_head *ent, *n;
 
-	list_for_each_safe(ent, n, &w1_masters) {
-		dev = list_entry(ent, struct w1_master, w1_master_entry);
+	list_for_each_entry(dev, &w1_masters, w1_master_entry) {
 		if (!dev->initialized)
 			continue;
 

drivers/w1/w1_int.h

···
 /*
- * 	w1_int.h
+ *	w1_int.h
  *
  * Copyright (c) 2004 Evgeniy Polyakov <[e-mail]>
- * 
+ *
  *
  * 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
···
 
 #include "w1.h"
 
-struct w1_master * w1_alloc_dev(u32, int, int, struct device_driver *, struct device *);
-void w1_free_dev(struct w1_master *dev);
 int w1_add_master_device(struct w1_bus_master *);
 void w1_remove_master_device(struct w1_bus_master *);
 void __w1_remove_master_device(struct w1_master *);

drivers/w1/w1_io.c

···
 /*
- * 	w1_io.c
+ *	w1_io.c
  *
  * Copyright (c) 2004 Evgeniy Polyakov <[e-mail]>
- * 
+ *
  *
  * 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
···
 	udelay(tm * w1_delay_parm);
 }
 
+static void w1_write_bit(struct w1_master *dev, int bit);
+static u8 w1_read_bit(struct w1_master *dev);
+
+/**
+ * Generates a write-0 or write-1 cycle and samples the level.
+ */
 u8 w1_touch_bit(struct w1_master *dev, int bit)
 {
 	if (dev->bus_master->touch_bit)
 		return dev->bus_master->touch_bit(dev->bus_master->data, bit);
-	else
+	else if (bit)
 		return w1_read_bit(dev);
+	else {
+		w1_write_bit(dev, 0);
+		return(0);
+	}
 }
 
-void w1_write_bit(struct w1_master *dev, int bit)
+/**
+ * Generates a write-0 or write-1 cycle.
+ * Only call if dev->bus_master->touch_bit is NULL
+ */
+static void w1_write_bit(struct w1_master *dev, int bit)
 {
 	if (bit) {
 		dev->bus_master->write_bit(dev->bus_master->data, 0);
···
 	}
 }
 
+/**
+ * Writes 8 bits.
+ *
+ * @param dev     the master device
+ * @param byte    the byte to write
+ */
 void w1_write_8(struct w1_master *dev, u8 byte)
 {
 	int i;
···
 		dev->bus_master->write_byte(dev->bus_master->data, byte);
 	else
 		for (i = 0; i < 8; ++i)
-			w1_write_bit(dev, (byte >> i) & 0x1);
+			w1_touch_bit(dev, (byte >> i) & 0x1);
 }
 
-u8 w1_read_bit(struct w1_master *dev)
+
+/**
+ * Generates a write-1 cycle and samples the level.
+ * Only call if dev->bus_master->touch_bit is NULL
+ */
+static u8 w1_read_bit(struct w1_master *dev)
 {
 	int result;
 
···
 	return result & 0x1;
 }
 
+/**
+ * Does a triplet - used for searching ROM addresses.
+ * Return bits:
+ *  bit 0 = id_bit
+ *  bit 1 = comp_bit
+ *  bit 2 = dir_taken
+ * If both bits 0 & 1 are set, the search should be restarted.
+ *
+ * @param dev     the master device
+ * @param bdir    the bit to write if both id_bit and comp_bit are 0
+ * @return        bit fields - see above
+ */
+u8 w1_triplet(struct w1_master *dev, int bdir)
+{
+	if ( dev->bus_master->triplet )
+		return(dev->bus_master->triplet(dev->bus_master->data, bdir));
+	else {
+		u8 id_bit   = w1_touch_bit(dev, 1);
+		u8 comp_bit = w1_touch_bit(dev, 1);
+		u8 retval;
+
+		if ( id_bit && comp_bit )
+			return(0x03);  /* error */
+
+		if ( !id_bit && !comp_bit ) {
+			/* Both bits are valid, take the direction given */
+			retval = bdir ? 0x04 : 0;
+		} else {
+			/* Only one bit is valid, take that direction */
+			bdir = id_bit;
+			retval = id_bit ? 0x05 : 0x02;
+		}
+
+		if ( dev->bus_master->touch_bit )
+			w1_touch_bit(dev, bdir);
+		else
+			w1_write_bit(dev, bdir);
+		return(retval);
+	}
+}
+
+/**
+ * Reads 8 bits.
+ *
+ * @param dev     the master device
+ * @return        the byte read
+ */
 u8 w1_read_8(struct w1_master * dev)
 {
 	int i;
···
 		res = dev->bus_master->read_byte(dev->bus_master->data);
 	else
 		for (i = 0; i < 8; ++i)
-			res |= (w1_read_bit(dev) << i);
+			res |= (w1_touch_bit(dev,1) << i);
 
 	return res;
 }
 
-void w1_write_block(struct w1_master *dev, u8 *buf, int len)
+/**
+ * Writes a series of bytes.
+ *
+ * @param dev     the master device
+ * @param buf     pointer to the data to write
+ * @param len     the number of bytes to write
+ * @return        the byte read
+ */
+void w1_write_block(struct w1_master *dev, const u8 *buf, int len)
 {
 	int i;
 
···
 			w1_write_8(dev, buf[i]);
 }
 
+/**
+ * Reads a series of bytes.
+ *
+ * @param dev     the master device
+ * @param buf     pointer to the buffer to fill
+ * @param len     the number of bytes to read
+ * @return        the number of bytes read
+ */
 u8 w1_read_block(struct w1_master *dev, u8 *buf, int len)
 {
 	int i;
···
 	return ret;
 }
 
+/**
+ * Issues a reset bus sequence.
+ *
+ * @param  dev The bus master pointer
+ * @return     0=Device present, 1=No device present or error
+ */
 int w1_reset_bus(struct w1_master *dev)
 {
-	int result = 0;
+	int result;
 
 	if (dev->bus_master->reset_bus)
 		result = dev->bus_master->reset_bus(dev->bus_master->data) & 0x1;
···
 	if (dev->bus_master->search)
 		dev->bus_master->search(dev->bus_master->data, cb);
 	else
-		w1_search(dev);
+		w1_search(dev, cb);
 }
 
-EXPORT_SYMBOL(w1_write_bit);
+EXPORT_SYMBOL(w1_touch_bit);
 EXPORT_SYMBOL(w1_write_8);
-EXPORT_SYMBOL(w1_read_bit);
 EXPORT_SYMBOL(w1_read_8);
 EXPORT_SYMBOL(w1_reset_bus);
 EXPORT_SYMBOL(w1_calc_crc8);

drivers/w1/w1_io.h

···
 /*
- * 	w1_io.h
+ *	w1_io.h
  *
  * Copyright (c) 2004 Evgeniy Polyakov <[e-mail]>
- * 
+ *
  *
  * 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
···
 
 void w1_delay(unsigned long);
 u8 w1_touch_bit(struct w1_master *, int);
-void w1_write_bit(struct w1_master *, int);
+u8 w1_triplet(struct w1_master *dev, int bdir);
 void w1_write_8(struct w1_master *, u8);
-u8 w1_read_bit(struct w1_master *);
 u8 w1_read_8(struct w1_master *);
 int w1_reset_bus(struct w1_master *);
 u8 w1_calc_crc8(u8 *, int);
-void w1_write_block(struct w1_master *, u8 *, int);
+void w1_write_block(struct w1_master *, const u8 *, int);
 u8 w1_read_block(struct w1_master *, u8 *, int);
 void w1_search_devices(struct w1_master *dev, w1_slave_found_callback cb);
 

drivers/w1/w1_log.h

···
 /*
- * 	w1_log.h
+ *	w1_log.h
  *
  * Copyright (c) 2004 Evgeniy Polyakov <[e-mail]>
- * 
+ *
  *
  * 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

drivers/w1/w1_netlink.h

···
 	W1_MASTER_REMOVE,
 };
 
-struct w1_netlink_msg 
+struct w1_netlink_msg
 {
 	__u8				type;
 	__u8				reserved[3];
 	union
 	{
-		struct w1_reg_num 	id;
+		struct w1_reg_num	id;
 		__u64			w1_id;
 		struct
 		{

drivers/w1/w1_smem.c

···
 /*
- * 	w1_smem.c
+ *	w1_smem.c
  *
  * Copyright (c) 2004 Evgeniy Polyakov <[e-mail]>
- * 
+ *
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the smems of the GNU General Public License as published by
···
 MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol, 64bit memory family.");
 
 static ssize_t w1_smem_read_name(struct device *, struct device_attribute *attr, char *);
-static ssize_t w1_smem_read_val(struct device *, struct device_attribute *attr, char *);
 static ssize_t w1_smem_read_bin(struct kobject *, char *, loff_t, size_t);
 
 static struct w1_family_ops w1_smem_fops = {
 	.rname = &w1_smem_read_name,
 	.rbin = &w1_smem_read_bin,
-	.rval = &w1_smem_read_val,
-	.rvalname = "id",
 };
 
 static ssize_t w1_smem_read_name(struct device *dev, struct device_attribute *attr, char *buf)
···
 	return sprintf(buf, "%s\n", sl->name);
 }
 
-static ssize_t w1_smem_read_val(struct device *dev, struct device_attribute *attr, char *buf)
-{
-	struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
-	int i;
-	ssize_t count = 0;
-	
-	for (i = 0; i < 8; ++i)
-		count += sprintf(buf + count, "%02x ", ((u8 *)&sl->reg_num)[i]);
-	count += sprintf(buf + count, "\n");
-
-	return count;
-}
-
 static ssize_t w1_smem_read_bin(struct kobject *kobj, char *buf, loff_t off, size_t count)
 {
 	struct w1_slave *sl = container_of(container_of(kobj, struct device, kobj),
-			      			struct w1_slave, dev);
+					   struct w1_slave, dev);
 	int i;
 
 	atomic_inc(&sl->refcnt);
···
 	for (i = 0; i < 8; ++i)
 		count += sprintf(buf + count, "%02x ", ((u8 *)&sl->reg_num)[i]);
 	count += sprintf(buf + count, "\n");
-	
+
 out:
 	up(&sl->master->mutex);
 out_dec:
···
 	return count;
 }
 
-static struct w1_family w1_smem_family = {
-	.fid = W1_FAMILY_SMEM,
+static struct w1_family w1_smem_family_01 = {
+	.fid = W1_FAMILY_SMEM_01,
+	.fops = &w1_smem_fops,
+};
+
+static struct w1_family w1_smem_family_81 = {
+	.fid = W1_FAMILY_SMEM_81,
 	.fops = &w1_smem_fops,
 };
 
 static int __init w1_smem_init(void)
 {
-	return w1_register_family(&w1_smem_family);
+	int err;
+
+	err = w1_register_family(&w1_smem_family_01);
+	if (err)
+		return err;
+	
+	err = w1_register_family(&w1_smem_family_81);
+	if (err) {
+		w1_unregister_family(&w1_smem_family_01);
+		return err;
+	}
+
+	return 0;
 }
 
 static void __exit w1_smem_fini(void)
 {
-	w1_unregister_family(&w1_smem_family);
+	w1_unregister_family(&w1_smem_family_01);
+	w1_unregister_family(&w1_smem_family_81);
 }
 
 module_init(w1_smem_init);

drivers/w1/w1_therm.c

···
 /*
- * 	w1_therm.c
+ *	w1_therm.c
  *
  * Copyright (c) 2004 Evgeniy Polyakov <[e-mail]>
- * 
+ *
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the therms of the GNU General Public License as published by
···
 MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol, temperature family.");
 
 static u8 bad_roms[][9] = {
-				{0xaa, 0x00, 0x4b, 0x46, 0xff, 0xff, 0x0c, 0x10, 0x87}, 
+				{0xaa, 0x00, 0x4b, 0x46, 0xff, 0xff, 0x0c, 0x10, 0x87},
 				{}
 			};
 
 static ssize_t w1_therm_read_name(struct device *, struct device_attribute *attr, char *);
-static ssize_t w1_therm_read_temp(struct device *, struct device_attribute *attr, char *);
 static ssize_t w1_therm_read_bin(struct kobject *, char *, loff_t, size_t);
 
 static struct w1_family_ops w1_therm_fops = {
 	.rname = &w1_therm_read_name,
 	.rbin = &w1_therm_read_bin,
-	.rval = &w1_therm_read_temp,
-	.rvalname = "temp1_input",
+};
+
+static struct w1_family w1_therm_family_DS18S20 = {
+	.fid = W1_THERM_DS18S20,
+	.fops = &w1_therm_fops,
+};
+
+static struct w1_family w1_therm_family_DS18B20 = {
+	.fid = W1_THERM_DS18B20,
+	.fops = &w1_therm_fops,
+};
+static struct w1_family w1_therm_family_DS1822 = {
+	.fid = W1_THERM_DS1822,
+	.fops = &w1_therm_fops,
+};
+
+struct w1_therm_family_converter
+{
+	u8			broken;
+	u16			reserved;
+	struct w1_family	*f;
+	int			(*convert)(u8 rom[9]);
+};
+
+static inline int w1_DS18B20_convert_temp(u8 rom[9]);
+static inline int w1_DS18S20_convert_temp(u8 rom[9]);
+
+static struct w1_therm_family_converter w1_therm_families[] = {
+	{
+		.f		= &w1_therm_family_DS18S20,
+		.convert 	= w1_DS18S20_convert_temp
+	},
+	{
+		.f		= &w1_therm_family_DS1822,
+		.convert 	= w1_DS18B20_convert_temp
+	},
+	{
+		.f		= &w1_therm_family_DS18B20,
+		.convert 	= w1_DS18B20_convert_temp
+	},
 };
 
 static ssize_t w1_therm_read_name(struct device *dev, struct device_attribute *attr, char *buf)
···
 	return sprintf(buf, "%s\n", sl->name);
 }
 
-static inline int w1_convert_temp(u8 rom[9])
+static inline int w1_DS18B20_convert_temp(u8 rom[9])
+{
+	int t = (rom[1] << 8) | rom[0];
+	t /= 16;
+	return t;
+}
+
+static inline int w1_DS18S20_convert_temp(u8 rom[9])
 {
 	int t, h;
+
+	if (!rom[7])
+		return 0;
 	
 	if (rom[1] == 0)
 		t = ((s32)rom[0] >> 1)*1000;
···
 	return t;
 }
 
-static ssize_t w1_therm_read_temp(struct device *dev, struct device_attribute *attr, char *buf)
+static inline int w1_convert_temp(u8 rom[9], u8 fid)
 {
-	struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
+	int i;
 
-	return sprintf(buf, "%d\n", w1_convert_temp(sl->rom));
+	for (i=0; i<sizeof(w1_therm_families)/sizeof(w1_therm_families[0]); ++i)
+		if (w1_therm_families[i].f->fid == fid)
+			return w1_therm_families[i].convert(rom);
+
+	return 0;
 }
 
 static int w1_therm_check_rom(u8 rom[9])
···
 static ssize_t w1_therm_read_bin(struct kobject *kobj, char *buf, loff_t off, size_t count)
 {
 	struct w1_slave *sl = container_of(container_of(kobj, struct device, kobj),
-			      			struct w1_slave, dev);
+					   struct w1_slave, dev);
 	struct w1_master *dev = sl->master;
 	u8 rom[9], crc, verdict;
 	int i, max_trying = 10;
···
 			unsigned int tm = 750;
 
 			memcpy(&match[1], (u64 *) & sl->reg_num, 8);
-			
+
 			w1_write_block(dev, match, 9);
 
 			w1_write_8(dev, W1_CONVERT_TEMP);
···
 
 			if (!w1_reset_bus (dev)) {
 				w1_write_block(dev, match, 9);
-				
+
 				w1_write_8(dev, W1_READ_SCRATCHPAD);
 				if ((count = w1_read_block(dev, rom, 9)) != 9) {
 					dev_warn(&dev->dev, "w1_read_block() returned %d instead of 9.\n", count);
···
 	for (i = 0; i < 9; ++i)
 		count += sprintf(buf + count, "%02x ", sl->rom[i]);
 	
-	count += sprintf(buf + count, "t=%d\n", w1_convert_temp(rom));
+	count += sprintf(buf + count, "t=%d\n", w1_convert_temp(rom, sl->family->fid));
 out:
 	up(&dev->mutex);
 out_dec:
···
 	return count;
 }
 
-static struct w1_family w1_therm_family = {
-	.fid = W1_FAMILY_THERM,
-	.fops = &w1_therm_fops,
-};
-
 static int __init w1_therm_init(void)
 {
-	return w1_register_family(&w1_therm_family);
+	int err, i;
+
+	for (i=0; i<sizeof(w1_therm_families)/sizeof(w1_therm_families[0]); ++i) {
+		err = w1_register_family(w1_therm_families[i].f);
+		if (err)
+			w1_therm_families[i].broken = 1;
+	}
+
+	return 0;
 }
 
 static void __exit w1_therm_fini(void)
 {
-	w1_unregister_family(&w1_therm_family);
+	int i;
+
+	for (i=0; i<sizeof(w1_therm_families)/sizeof(w1_therm_families[0]); ++i)
+		if (!w1_therm_families[i].broken)
+			w1_unregister_family(w1_therm_families[i].f);
 }
 
 module_init(w1_therm_init);