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

@@ -30,7 +30,7 @@ config W1_DS9490
 	  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

drivers/w1/ds_w1_bridge.c

@@ -83,11 +83,11 @@ static u8 ds9490r_read_byte(unsigned long data)
 	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/w1.h

@@ -79,31 +79,81 @@ struct w1_slave
 	struct completion	dev_released;
 
 	struct bin_attribute	attr_bin;
-	struct device_attribute	attr_name, attr_val;
+	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
 {
+	/** the first parameter in all the functions below */
 	unsigned long	data;
 
+	/**
+	 * Sample the line level
+	 * @return the level read (0 or 1)
+	 */
 	u8		(*read_bit)(unsigned long);
+
+	/** 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);
-	void			(*write_block)(unsigned long, u8 *, int);
 
-  	u8			(*touch_bit)(unsigned long, u8);
+	/** 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
 {
 	struct list_head	w1_master_entry;
@@ -115,13 +165,15 @@ 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;
 
@@ -137,8 +189,7 @@ struct w1_master
 };
 
 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

@@ -27,10 +27,11 @@
 
 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;
@@ -60,9 +61,10 @@ int w1_register_family(struct w1_family *newf)
 		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

@@ -27,8 +27,11 @@
 #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
 
@@ -36,9 +39,6 @@ struct w1_family_ops
 {
 	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

drivers/w1/w1_int.c

@@ -39,8 +39,9 @@ extern spinlock_t w1_mlock;
 
 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;
@@ -68,6 +69,7 @@ struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl,
 	dev->initialized	= 0;
 	dev->id			= id;
 	dev->slave_ttl		= slave_ttl;
+        dev->search_count	= -1; /* continual scan */
 
 	atomic_set(&dev->refcnt, 2);
 
@@ -105,7 +107,7 @@ struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl,
 	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)
@@ -120,6 +122,13 @@ int w1_add_master_device(struct w1_bus_master *master)
 	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 -ENOMEM;
@@ -153,7 +162,7 @@ int w1_add_master_device(struct w1_bus_master *master)
 	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",
@@ -171,7 +180,7 @@ void __w1_remove_master_device(struct w1_master *dev)
 	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,
@@ -197,10 +206,8 @@ void __w1_remove_master_device(struct w1_master *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

@@ -27,8 +27,6 @@
 
 #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

@@ -55,15 +55,29 @@ void w1_delay(unsigned long tm)
 	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);
@@ -78,6 +92,12 @@ void w1_write_bit(struct w1_master *dev, int bit)
 	}
 }
 
+/**
+ * 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;
@@ -86,10 +106,15 @@ void w1_write_8(struct w1_master *dev, u8 byte)
 		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;
 
@@ -104,6 +129,53 @@ u8 w1_read_bit(struct w1_master *dev)
 	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;
@@ -113,12 +185,20 @@ u8 w1_read_8(struct w1_master * dev)
 		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;
 
@@ -129,6 +209,14 @@ void w1_write_block(struct w1_master *dev, u8 *buf, int len)
 			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;
@@ -145,9 +233,15 @@ u8 w1_read_block(struct w1_master *dev, u8 *buf, int len)
 	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;
@@ -180,12 +274,11 @@ void w1_search_devices(struct w1_master *dev, w1_slave_found_callback cb)
 	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

@@ -26,13 +26,12 @@
 
 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_smem.c

@@ -37,14 +37,11 @@ MODULE_AUTHOR("Evgeniy Polyakov <johnpol@2ka.mipt.ru>");
 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)
@@ -54,19 +51,6 @@ static ssize_t w1_smem_read_name(struct device *dev, struct device_attribute *at
 	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),
@@ -99,19 +83,37 @@ static ssize_t w1_smem_read_bin(struct kobject *kobj, char *buf, loff_t off, siz
 	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

@@ -43,14 +43,51 @@ static u8 bad_roms[][9] = {
 			};
 
 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)
@@ -60,10 +97,20 @@ static ssize_t w1_therm_read_name(struct device *dev, struct device_attribute *a
 	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;
 	else
@@ -77,11 +124,15 @@ static inline int w1_convert_temp(u8 rom[9])
 	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;
+
+	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 sprintf(buf, "%d\n", w1_convert_temp(sl->rom));
+	return 0;
 }
 
 static int w1_therm_check_rom(u8 rom[9])
@@ -176,7 +227,7 @@ static ssize_t w1_therm_read_bin(struct kobject *kobj, char *buf, loff_t off, si
 	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:
@@ -186,19 +237,26 @@ static ssize_t w1_therm_read_bin(struct kobject *kobj, char *buf, loff_t off, si
 	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);