(mds) add ds1621 driver from Christian Zuckschwerdt (zany@triq.net)

git-svn-id: http://lm-sensors.org/svn/lm-sensors/trunk@935 7894878c-1315-0410-8ee3-d5d059ff63e0
2025-08-30 22:05:11 +00:00 · 2000-11-26 23:07:17 +00:00
parent bd1b923045
commit bb4b723e68
14 changed files with 694 additions and 6 deletions
--- a/9
+++ b/9
@@ -20,17 +20,18 @@ ask CVS about it:
 2.5.5 (2000????)
  Chip modules (all): Update mutex definition (works now for new 2.2 kernels)
  File sensors.conf.eg: Add mtp008 entries
-  Library: Add mtp008 support
+  Library: Add ds1621, mtp008 support
  Module adm1021: Add support for adm1021a / adm1023
-  Module i2c-ali1535: Enhance error checking and recovery; add mutex
  Module ddcmon: allow force and force_ddcmon parameters
+  Module ds1621: new
+  Module i2c-ali1535: Enhance error checking and recovery; add mutex
  Module lm87: update voltage calculations
  Module mtp008: new
  Module pcf8574: change update time to 5 seconds
  Module w83781d: fix beep setting via /proc
  Program mkpatch.pl: more fixes
-  Program sensors: Add mtp008 support, add -f (Fahrenheit) option
-  Program sensors-detect: Add mtp008 detection
+  Program sensors: Add ds1621, mtp008 support, add -f (Fahrenheit) option
+  Program sensors-detect: Add ds1621, mtp008 detection

 2.5.4 (20001012)
  Module i2c-viapro: Add support for Via 596B (0x3051)
--- a/2
+++ b/2
@@ -51,7 +51,7 @@ At least the following hardware sensor chips are supported:
  Analog Devices ADM1021, ADM1021A, ADM1022,
                 ADM1023, ADM1025, and ADM9240
  Asus AS99127F
-  Dallas Semiconductor DS1780, DS75, and DS1775
+  Dallas Semiconductor DS75, DS1621, DS1775, and DS1780
  Hewlett Packard Maxilife (several revisions including '99 NBA)
  Genesys Logic GL518SM (rev 00, 80), GL520SM, GL523SM
  Intel Xeon processor embedded sensors
--- a/doc/chips/SUMMARY
+++ b/doc/chips/SUMMARY
@@ -56,6 +56,9 @@ adm9240
 	ds1780		1	6	2	1 dac	yes	no
 	lm81		1	6	2	1 dac	yes	no

+ds1621
+	ds1621		1	-	-	-	yes	no
+
 gl518sm
        gl518sm (r00)	1	1-4	2	-	yes	no
        gl518sm (r80)	1	4	2	-	yes	no
--- a/doc/chips/ds1621
+++ b/doc/chips/ds1621
@@ -0,0 +1,68 @@
+Kernel driver `ds1621.o'
+=====================
+
+Status: Complete and tested, alarms experimental
+
+Supported chips: 
+  * Dallas Semiconductor DS1621
+    Prefix: `ds1621'
+    Addresses scanned: I2C 0x48 - 0x4f (inclusive)
+    Datasheet: Publicly available at the Dallas Semiconductor website
+               http://www.dalsemi.com
+
+Author: Christian W. Zuckschwerdt <zany@triq.net>
+
+
+Module Parameters
+-----------------
+
+* force: short array (min = 1, max = 48)
+  List of adapter,address pairs to boldly assume to be present
+* force_ds1621: short array (min = 1, max = 48)
+  List of adapter,address pairs which are unquestionably assumed to contain
+  a `ds1621' chip
+* ignore: short array (min = 1, max = 48)
+  List of adapter,address pairs not to scan
+* ignore_range: short array (min = 1, max = 48)
+  List of adapter,start-addr,end-addr triples not to scan
+* probe: short array (min = 1, max = 48)
+  List of adapter,address pairs to scan additionally
+* probe_range: short array (min = 1, max = 48)
+  List of adapter,start-addr,end-addr triples to scan additionally
+
+
+Description
+-----------
+
+The DS1621 implements one temperature sensor. Limits can be set through the
+Overtemperature register and Hysteresis register. Each value can be 
+set and read to half-degree accuracy.
+An alarm is issued when the temperature gets higher then the Overtemperature
+value; or drops below the Hysteresis value.
+
+It stays on until reset by the kernel module.
+
+All temperatures are in degrees Celcius, and are guaranteed within a 
+range of -55 to +125 degrees.
+
+The DS1621 supplies the temperature data in a format common with chips
+like the LM75, LM77 and DS75, DS1775.
+While the DS1621 has three additional bits of accuracy
+(12 vs. 9 for the LM75), the additional bits are not supported.
+
+
+Chip Features
+-------------
+
+Chip `ds1621'
+          LABEL     LABEL CLASS   COMPUTE CLASS ACCESS MAGNITUDE
+           temp            NONE            NONE      R     1
+      temp_hyst            temp            temp      RW    1
+      temp_over            temp            temp      RW    1
+         alarms            NONE            NONE      R     0
+
+          LABEL                           FEATURE SYMBOL     SYSCTL FILE:OFFSET
+           temp                      SENSORS_DS1621_TEMP            temp:3
+      temp_hyst                 SENSORS_DS1621_TEMP_HYST            temp:2
+      temp_over                 SENSORS_DS1621_TEMP_OVER            temp:1
+         alarms                    SENSORS_DS1621_ALARMS          alarms:1
--- a/kernel/chips/Module.mk
+++ b/kernel/chips/Module.mk
@@ -37,6 +37,9 @@ endif
 ifneq ($(shell if grep -q '^CONFIG_SENSORS_ADM9240=y' $(LINUX)/.config; then echo 1; fi),1)
 KERNELCHIPSTARGETS += $(MODULE_DIR)/adm9240.o
 endif
+ifneq ($(shell if grep -q '^CONFIG_SENSORS_DS1621=y' $(LINUX)/.config; then echo 1; fi),1)
+KERNELCHIPSTARGETS += $(MODULE_DIR)/ds1621.o
+endif
 ifneq ($(shell if grep -q '^CONFIG_SENSORS_EEPROM=y' $(LINUX)/.config; then echo 1; fi),1)
 KERNELCHIPSTARGETS += $(MODULE_DIR)/eeprom.o
 endif
--- a/kernel/chips/ds1621.c
+++ b/kernel/chips/ds1621.c
@@ -0,0 +1,509 @@
+/*
+    ds1621.c - Part of lm_sensors, Linux kernel modules for hardware
+             monitoring
+    Christian W. Zuckschwerdt  <zany@triq.net>  2000-11-23
+    based on lm75.c by Frodo Looijaard <frodol@dds.nl>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+/* Supports DS1621. See doc/chips/ds1621 for details */
+
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/malloc.h>
+#include <linux/i2c.h>
+#include "sensors.h"
+#include "i2c-isa.h"
+#include "version.h"
+#include <linux/init.h>
+
+
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,2,18)) || \
+    (LINUX_VERSION_CODE == KERNEL_VERSION(2,3,0))
+#define init_MUTEX(s) do { *(s) = MUTEX; } while(0)
+#endif
+
+#ifndef THIS_MODULE
+#define THIS_MODULE NULL
+#endif
+
+/* Addresses to scan */
+static unsigned short normal_i2c[] = { SENSORS_I2C_END };
+static unsigned short normal_i2c_range[] = { 0x48, 0x4f, SENSORS_I2C_END };
+static unsigned int normal_isa[] = { SENSORS_ISA_END };
+static unsigned int normal_isa_range[] = { SENSORS_ISA_END };
+
+/* Insmod parameters */
+SENSORS_INSMOD_1(ds1621);
+
+/* Many DS1621 constants specified below - most aren't used */
+
+/* Config register used for detection         */
+/*  7    6    5    4    3    2    1    0      */
+/* |Done|THF |TLF |NVB | 1  | 0  |POL |1SHOT| */
+#define DS1621_REG_CONFIG_MASK 0x0C
+#define DS1621_REG_CONFIG_VAL 0x08
+
+/* The DS1621 registers */
+#define DS1621_REG_TEMP 0xAA /* word, RO */
+#define DS1621_REG_TEMP_OVER 0xA1 /* word, RW */
+#define DS1621_REG_TEMP_HYST 0xA2 /* word, RW -- it's a low temp trigger */
+#define DS1621_REG_CONF 0xAC /* byte, RW */
+#define DS1621_REG_TEMP_COUNTER 0xA8 /* byte, RO */
+#define DS1621_REG_TEMP_SLOPE 0xA9 /* byte, RO */
+#define DS1621_COM_START 0xEE /* no data */
+#define DS1621_COM_STOP 0x22 /* no data */
+
+/* Conversions. Rounding and limit checking is only done on the TO_REG
+   variants. Note that you should be a bit careful with which arguments
+   these macros are called: arguments may be evaluated more than once.
+   Fixing this is just not worth it. */
+#define TEMP_FROM_REG(val) ((((val & 0x7fff) >> 7) * 5) | \
+                            ((val & 0x8000)?-256:0))
+#define TEMP_TO_REG(val)   (SENSORS_LIMIT((val<0 ? (0x200+((val)/5))<<7 : \
+                                          (((val) + 2) / 5) << 7),0,0xffff))
+#define ALARMS_FROM_REG(val) ((val) & \
+                              (DS1621_ALARM_TEMP_HIGH | DS1621_ALARM_TEMP_LOW))
+
+/* Initial values */
+#define DS1621_INIT_TEMP_OVER 600
+#define DS1621_INIT_TEMP_HYST 0 /* 500 would cause an alarm at room temp. */
+
+/* Each client has this additional data */
+struct ds1621_data {
+	int sysctl_id;
+
+	struct semaphore update_lock;
+	char valid;		/* !=0 if following fields are valid */
+	unsigned long last_updated;	/* In jiffies */
+
+	u16 temp, temp_over, temp_hyst;	/* Register values */
+	u8 conf;			/* Register encoding, combined */
+};
+
+#ifdef MODULE
+extern int init_module(void);
+extern int cleanup_module(void);
+#endif				/* MODULE */
+
+#ifdef MODULE
+static
+#else
+extern
+#endif
+int __init sensors_ds1621_init(void);
+static int __init ds1621_cleanup(void);
+static int ds1621_attach_adapter(struct i2c_adapter *adapter);
+static int ds1621_detect(struct i2c_adapter *adapter, int address,
+			 unsigned short flags, int kind);
+static void ds1621_init_client(struct i2c_client *client);
+static int ds1621_detach_client(struct i2c_client *client);
+static int ds1621_command(struct i2c_client *client, unsigned int cmd,
+			  void *arg);
+static void ds1621_inc_use(struct i2c_client *client);
+static void ds1621_dec_use(struct i2c_client *client);
+static u16 swap_bytes(u16 val);
+static int ds1621_read_value(struct i2c_client *client, u8 reg);
+static int ds1621_write_value(struct i2c_client *client, u8 reg, u16 value);
+static void ds1621_temp(struct i2c_client *client, int operation,
+			int ctl_name, int *nrels_mag, long *results);
+static void ds1621_alarms(struct i2c_client *client, int operation,
+			  int ctl_name, int *nrels_mag, long *results);
+static void ds1621_enable(struct i2c_client *client, int operation,
+			  int ctl_name, int *nrels_mag, long *results);
+static void ds1621_update_client(struct i2c_client *client);
+
+
+/* This is the driver that will be inserted */
+static struct i2c_driver ds1621_driver = {
+	/* name */ "DS1621 sensor driver",
+	/* id */ I2C_DRIVERID_DS1621,
+	/* flags */ I2C_DF_NOTIFY,
+	/* attach_adapter */ &ds1621_attach_adapter,
+	/* detach_client */ &ds1621_detach_client,
+	/* command */ &ds1621_command,
+	/* inc_use */ &ds1621_inc_use,
+	/* dec_use */ &ds1621_dec_use
+};
+
+/* These files are created for each detected DS1621. This is just a template;
+   though at first sight, you might think we could use a statically
+   allocated list, we need some way to get back to the parent - which
+   is done through one of the 'extra' fields which are initialized
+   when a new copy is allocated. */
+static ctl_table ds1621_dir_table_template[] = {
+	{DS1621_SYSCTL_TEMP, "temp", NULL, 0, 0644, NULL, &sensors_proc_real,
+	 &sensors_sysctl_real, NULL, &ds1621_temp},
+	{DS1621_SYSCTL_ALARMS, "alarms", NULL, 0, 0444, NULL,
+	 &sensors_proc_real, &sensors_sysctl_real, NULL, &ds1621_alarms},
+	{DS1621_SYSCTL_ENABLE, "enable", NULL, 0, 0644, NULL,
+	 &sensors_proc_real, &sensors_sysctl_real, NULL, &ds1621_enable},
+	{0}
+};
+
+/* Used by init/cleanup */
+static int __initdata ds1621_initialized = 0;
+
+static int ds1621_id = 0;
+
+int ds1621_attach_adapter(struct i2c_adapter *adapter)
+{
+	return sensors_detect(adapter, &addr_data, ds1621_detect);
+}
+
+/* This function is called by sensors_detect */
+int ds1621_detect(struct i2c_adapter *adapter, int address,
+		unsigned short flags, int kind)
+{
+	int i, conf;
+	struct i2c_client *new_client;
+	struct ds1621_data *data;
+	int err = 0;
+	const char *type_name, *client_name;
+
+	/* Make sure we aren't probing the ISA bus!! This is just a safety check
+	   at this moment; sensors_detect really won't call us. */
+#ifdef DEBUG
+	if (i2c_is_isa_adapter(adapter)) {
+		printk
+		 ("ds1621.o: ds1621_detect called for an ISA bus adapter?!?\n");
+		return 0;
+	}
+#endif
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
+				     I2C_FUNC_SMBUS_WORD_DATA))
+		    goto ERROR0;
+
+	/* OK. For now, we presume we have a valid client. We now create the
+	   client structure, even though we cannot fill it completely yet.
+	   But it allows us to access ds1621_{read,write}_value. */
+	if (!(new_client = kmalloc(sizeof(struct i2c_client) +
+				   sizeof(struct ds1621_data),
+				   GFP_KERNEL))) {
+		err = -ENOMEM;
+		goto ERROR0;
+	}
+
+	data = (struct ds1621_data *) (new_client + 1);
+	new_client->addr = address;
+	new_client->data = data;
+	new_client->adapter = adapter;
+	new_client->driver = &ds1621_driver;
+	new_client->flags = 0;
+
+	/* Now, we do the remaining detection. It is lousy. */
+	if (kind < 0) {
+		conf = i2c_smbus_read_byte_data(new_client,
+						DS1621_REG_CONF);
+		if ((conf & DS1621_REG_CONFIG_MASK)
+		    != DS1621_REG_CONFIG_VAL)
+			goto ERROR1;
+	}
+
+	/* Determine the chip type - only one kind supported! */
+	if (kind <= 0)
+		kind = ds1621;
+
+	if (kind == ds1621) {
+		type_name = "ds1621";
+		client_name = "DS1621 chip";
+	} else {
+#ifdef DEBUG
+		printk("ds1621.o: Internal error: unknown kind (%d)?!?",
+		       kind);
+#endif
+		goto ERROR1;
+	}
+
+	/* Fill in remaining client fields and put it into the global list */
+	strcpy(new_client->name, client_name);
+
+	new_client->id = ds1621_id++;
+	data->valid = 0;
+	init_MUTEX(&data->update_lock);
+
+	/* Tell the I2C layer a new client has arrived */
+	if ((err = i2c_attach_client(new_client)))
+		goto ERROR3;
+
+	/* Register a new directory entry with module sensors */
+	if ((i = sensors_register_entry(new_client, type_name,
+					ds1621_dir_table_template,
+					THIS_MODULE)) < 0) {
+		err = i;
+		goto ERROR4;
+	}
+	data->sysctl_id = i;
+
+	ds1621_init_client(new_client);
+	return 0;
+
+/* OK, this is not exactly good programming practice, usually. But it is
+   very code-efficient in this case. */
+
+      ERROR4:
+	i2c_detach_client(new_client);
+      ERROR3:
+      ERROR1:
+	kfree(new_client);
+      ERROR0:
+	return err;
+}
+
+int ds1621_detach_client(struct i2c_client *client)
+{
+	int err;
+
+#ifdef MODULE
+	if (MOD_IN_USE)
+		return -EBUSY;
+#endif
+
+
+	sensors_deregister_entry(((struct ds1621_data *) (client->data))->
+				 sysctl_id);
+
+	if ((err = i2c_detach_client(client))) {
+		printk
+	   ("ds1621.o: Client deregistration failed, client not detached.\n");
+		return err;
+	}
+
+	kfree(client);
+
+	return 0;
+}
+
+
+/* No commands defined yet */
+int ds1621_command(struct i2c_client *client, unsigned int cmd, void *arg)
+{
+	return 0;
+}
+
+/* Nothing here yet */
+void ds1621_inc_use(struct i2c_client *client)
+{
+#ifdef MODULE
+	MOD_INC_USE_COUNT;
+#endif
+}
+
+/* Nothing here yet */
+void ds1621_dec_use(struct i2c_client *client)
+{
+#ifdef MODULE
+	MOD_DEC_USE_COUNT;
+#endif
+}
+
+u16 swap_bytes(u16 val)
+{
+	return (val >> 8) | (val << 8);
+}
+
+/* All registers are word-sized, except for the configuration register.
+   DS1621 uses a high-byte first convention, which is exactly opposite to
+   the usual practice. */
+int ds1621_read_value(struct i2c_client *client, u8 reg)
+{
+	if ((reg == DS1621_REG_CONF) || (reg == DS1621_REG_TEMP_COUNTER)
+	    || (reg == DS1621_REG_TEMP_SLOPE))
+		return i2c_smbus_read_byte_data(client, reg);
+	else
+		return swap_bytes(i2c_smbus_read_word_data(client, reg));
+}
+
+/* All registers are word-sized, except for the configuration register.
+   DS1621 uses a high-byte first convention, which is exactly opposite to
+   the usual practice. */
+int ds1621_write_value(struct i2c_client *client, u8 reg, u16 value)
+{
+	if ((reg == DS1621_REG_CONF) || (reg == DS1621_REG_TEMP_COUNTER)
+	    || (reg == DS1621_REG_TEMP_SLOPE))
+		return i2c_smbus_write_byte_data(client, reg, value);
+	else
+		return i2c_smbus_write_word_data(client, reg,
+						 swap_bytes(value));
+}
+
+void ds1621_init_client(struct i2c_client *client)
+{
+	/* Initialize the DS1621 chip */
+	ds1621_write_value(client, DS1621_REG_TEMP_OVER,
+			 TEMP_TO_REG(DS1621_INIT_TEMP_OVER));
+	ds1621_write_value(client, DS1621_REG_TEMP_HYST,
+			 TEMP_TO_REG(DS1621_INIT_TEMP_HYST));
+	ds1621_write_value(client, DS1621_REG_CONF, 0);
+
+	/* perhaps we should start the continous conversion? For now */
+	/* you got to do that yourself using the "enable" in proc */
+}
+
+void ds1621_update_client(struct i2c_client *client)
+{
+	struct ds1621_data *data = client->data;
+	u8 new_conf;
+
+	down(&data->update_lock);
+
+	if ((jiffies - data->last_updated > HZ + HZ / 2) ||
+	    (jiffies < data->last_updated) || !data->valid) {
+
+#ifdef DEBUG
+		printk("Starting ds1621 update\n");
+#endif
+
+		data->conf = ds1621_read_value(client, DS1621_REG_CONF);
+		/* we should wait for the DONE bit... */
+		data->temp = ds1621_read_value(client, DS1621_REG_TEMP);
+		data->temp_over = ds1621_read_value(client,
+		                                    DS1621_REG_TEMP_OVER);
+		data->temp_hyst =
+		    ds1621_read_value(client, DS1621_REG_TEMP_HYST);
+
+		/* reset alarms if neccessary */
+		new_conf = data->conf;
+		if (data->temp < data->temp_over)
+			new_conf &= ~DS1621_ALARM_TEMP_HIGH;
+		if (data->temp > data->temp_hyst)
+			new_conf &= ~DS1621_ALARM_TEMP_LOW;
+		if (data->conf != new_conf)
+			ds1621_write_value(client, DS1621_REG_CONF,
+					   new_conf);
+
+		data->last_updated = jiffies;
+		data->valid = 1;
+	}
+
+	up(&data->update_lock);
+}
+
+
+void ds1621_temp(struct i2c_client *client, int operation, int ctl_name,
+		 int *nrels_mag, long *results)
+{
+	struct ds1621_data *data = client->data;
+	if (operation == SENSORS_PROC_REAL_INFO)
+		*nrels_mag = 1;
+	else if (operation == SENSORS_PROC_REAL_READ) {
+		ds1621_update_client(client);
+		results[0] = TEMP_FROM_REG(data->temp_over);
+		results[1] = TEMP_FROM_REG(data->temp_hyst);
+		results[2] = TEMP_FROM_REG(data->temp);
+		*nrels_mag = 3;
+	} else if (operation == SENSORS_PROC_REAL_WRITE) {
+		if (*nrels_mag >= 1) {
+			data->temp_over = TEMP_TO_REG(results[0]);
+			ds1621_write_value(client, DS1621_REG_TEMP_OVER,
+					 data->temp_over);
+		}
+		if (*nrels_mag >= 2) {
+			data->temp_hyst = TEMP_TO_REG(results[1]);
+			ds1621_write_value(client, DS1621_REG_TEMP_HYST,
+					 data->temp_hyst);
+		}
+	}
+}
+
+void ds1621_alarms(struct i2c_client *client, int operation, int ctl_name,
+		   int *nrels_mag, long *results)
+{
+	struct ds1621_data *data = client->data;
+	if (operation == SENSORS_PROC_REAL_INFO)
+		*nrels_mag = 0;
+	else if (operation == SENSORS_PROC_REAL_READ) {
+		ds1621_update_client(client);
+		results[0] = ALARMS_FROM_REG(data->conf);
+		*nrels_mag = 1;
+	}
+}
+
+void ds1621_enable(struct i2c_client *client, int operation, int ctl_name,
+		   int *nrels_mag, long *results)
+{
+	/* If you really screw up your chip (like I did) this is */
+	/* sometimes needed to (re)start the continous conversion */
+	/* there is no data to read so this might hang your SMBus! */
+
+	if (operation == SENSORS_PROC_REAL_INFO)
+		*nrels_mag = 0;
+	else if (operation == SENSORS_PROC_REAL_READ) {
+		*nrels_mag = 0;
+	} else if (operation == SENSORS_PROC_REAL_WRITE) {
+		if (*nrels_mag >= 1) {
+			if (results[0]) {
+				ds1621_read_value(client, DS1621_COM_START);
+			} else {
+				ds1621_read_value(client, DS1621_COM_STOP);
+			}
+		} else {
+			ds1621_read_value(client, DS1621_COM_START);
+		}
+	}
+}
+
+int __init sensors_ds1621_init(void)
+{
+	int res;
+
+	printk("ds1621.o version %s (%s)\n", LM_VERSION, LM_DATE);
+	ds1621_initialized = 0;
+	if ((res = i2c_add_driver(&ds1621_driver))) {
+		printk
+	    ("ds1621.o: Driver registration failed, module not inserted.\n");
+		ds1621_cleanup();
+		return res;
+	}
+	ds1621_initialized++;
+	return 0;
+}
+
+int __init ds1621_cleanup(void)
+{
+	int res;
+
+	if (ds1621_initialized >= 1) {
+		if ((res = i2c_del_driver(&ds1621_driver))) {
+			printk
+			    ("ds1621.o: Driver deregistration failed, module not removed.\n");
+			return res;
+		}
+		ds1621_initialized--;
+	}
+
+	return 0;
+}
+
+EXPORT_NO_SYMBOLS;
+
+#ifdef MODULE
+
+MODULE_AUTHOR("Christian W. Zuckschwerdt <zany@triq.net>");
+MODULE_DESCRIPTION("DS1621 driver");
+
+int init_module(void)
+{
+	return sensors_ds1621_init();
+}
+
+int cleanup_module(void)
+{
+	return ds1621_cleanup();
+}
+
+#endif				/* MODULE */
--- a/kernel/include/sensors.h
+++ b/kernel/include/sensors.h
@@ -402,6 +402,7 @@ extern inline int SENSORS_LIMIT(long value, long low, long high)
 #define I2C_DRIVERID_LM87 1021
 #define I2C_DRIVERID_PCF8574 1022
 #define I2C_DRIVERID_MTP008 1023
+#define I2C_DRIVERID_DS1621 1024

 /* Sysctl IDs */
 #ifdef DEV_HWMON
@@ -815,5 +816,11 @@ struct sensors_chips_data {
 #define MTP008_ALARM_TEMP2	0x0100
 #define MTP008_ALARM_TEMP3	0x0200

+#define DS1621_SYSCTL_TEMP 1200	/* Degrees Celcius * 10 */
+#define DS1621_SYSCTL_ALARMS 2001	/* bitvector */
+#define DS1621_ALARM_TEMP_HIGH 0x40
+#define DS1621_ALARM_TEMP_LOW 0x20
+#define DS1621_SYSCTL_ENABLE 2002
+
 #endif				/* def SENSORS_SENSORS_H */

--- a/kernel/sensors.c
+++ b/kernel/sensors.c
@@ -922,6 +922,9 @@ extern int sensors_adm1021_init(void);
 #ifdef CONFIG_SENSORS_ADM9240
 extern int sensors_adm9024_init(void);
 #endif
+#ifdef CONFIG_SENSORS_DS1621
+extern int sensors_ds1621_init(void);
+#endif
 #ifdef CONFIG_SENSORS_GL518SM
 extern int sensors_gl518sm_init(void);
 #endif
@@ -956,6 +959,9 @@ int __init sensors_init_all(void)
 #ifdef CONFIG_SENSORS_ADM9024
 	sensors_adm9024_init();
 #endif
+#ifdef CONFIG_SENSORS_DS1621
+	sensors_ds1621_init();
+#endif
 #ifdef CONFIG_SENSORS_GL518SM
 	sensors_gl518sm_init();
 #endif
--- a/lib/chips.c
+++ b/lib/chips.c
@@ -1972,6 +1972,21 @@ static sensors_chip_feature mtp008_features[] =
    { 0 }
  };

+static sensors_chip_feature ds1621_features[] =
+  {
+    { SENSORS_DS1621_TEMP, "temp", SENSORS_NO_MAPPING, SENSORS_NO_MAPPING,
+                         SENSORS_MODE_R, DS1621_SYSCTL_TEMP, VALUE(3), 1 },
+    { SENSORS_DS1621_TEMP_HYST, "temp_hyst", SENSORS_DS1621_TEMP,
+                              SENSORS_DS1621_TEMP, SENSORS_MODE_RW, 
+                              DS1621_SYSCTL_TEMP, VALUE(2), 1 },
+    { SENSORS_DS1621_TEMP_OVER, "temp_over", SENSORS_DS1621_TEMP,
+                              SENSORS_DS1621_TEMP, SENSORS_MODE_RW, 
+                              DS1621_SYSCTL_TEMP, VALUE(1), 1 },
+    { SENSORS_DS1621_ALARMS, "alarms", SENSORS_NO_MAPPING, SENSORS_NO_MAPPING,
+                           SENSORS_MODE_R, DS1621_SYSCTL_ALARMS, VALUE(1), 0 },
+    { 0 }
+  };
+
 sensors_chip_features sensors_chip_features_list[] =
 {
 { SENSORS_LM78_PREFIX, lm78_features },
@@ -2014,5 +2029,6 @@ sensors_chip_features sensors_chip_features_list[] =
 { SENSORS_EEPROM_PREFIX, eeprom_features },
 { SENSORS_LM87_PREFIX, lm87_features },
 { SENSORS_MTP008_PREFIX, mtp008_features },
+ { SENSORS_DS1621_PREFIX, ds1621_features },
 { 0 }
 };
--- a/lib/chips.h
+++ b/lib/chips.h
@@ -901,4 +901,13 @@
 #define SENSORS_MTP008_ALARMS          81 /* R */
 #define SENSORS_MTP008_BEEP            82 /* RW */

+/* DS1621 chips. */
+
+#define SENSORS_DS1621_PREFIX "ds1621"
+
+#define SENSORS_DS1621_TEMP 51 /* R */
+#define SENSORS_DS1621_TEMP_HYST 52 /* RW */
+#define SENSORS_DS1621_TEMP_OVER 53 /* RW */
+#define SENSORS_DS1621_ALARMS 81 /* R */
+
 #endif /* def LIB_SENSORS_CHIPS_H */
--- a/prog/detect/sensors-detect
+++ b/prog/detect/sensors-detect
@@ -360,7 +360,7 @@ use subs qw(mtp008_detect lm78_detect lm78_isa_detect lm78_alias_detect
            adm9240_detect adm1021_detect sis5595_isa_detect eeprom_detect
            via686a_isa_detect adm1022_detect ltc1710_detect gl525sm_detect
            lm87_detect ite_detect ite_isa_detect ite_alias_detect
-            ddcmonitor_detect);
+            ddcmonitor_detect ds1621_detect);

 # This is a list of all recognized chips. 
 # Each entry must have the following fields:
@@ -520,6 +520,12 @@ use subs qw(mtp008_detect lm78_detect lm78_isa_detect lm78_alias_detect
       i2c_addrs => [0x2c..0x2f],
       i2c_detect => sub { adm9240_detect 0, @_ }
     },
+     {
+       name => "Dallas Semiconductor DS1621",
+       driver => "ds1621",
+       i2c_addrs => [0x48..0x4f],
+       i2c_detect => sub { ds1621_detect @_},
+     } ,
     {
       name => "Dallas Semiconductor DS1780",
       driver => "adm9240",
@@ -1566,6 +1572,26 @@ sub lm75_detect
  return (3);
 }
  
+# $_[0]: A reference to the file descriptor to access this chip.
+#        We may assume an i2c_set_slave_addr was already done.
+# $_[1]: Address
+# Returns: undef if not detected, (3) if detected,
+#   (6) or (9) if even more bits match. 
+# Registers used:
+#   0xAC: Configuration
+# Detection is weak. We check if Bit 3 is set and Bit 2 is clear.
+# The DS1621 will aways have a config like 0x????10??. A even better
+# match would be 0x0??01000.
+sub ds1621_detect
+{
+  my $i;
+  my ($file,$addr) = @_;
+  my $conf = i2c_smbus_read_byte_data($file,0xAC);
+  return (9) if ($conf & 0x9F) == 0x98;
+  return (6) if ($conf & 0x0F) == 0x08;
+  return (3) if ($conf & 0x0C) == 0x08;
+  return ;
+}

 # $_[0]: A reference to the file descriptor to access this chip.
 #        We may assume an i2c_set_slave_addr was already done.
--- a/prog/sensors/chips.c
+++ b/prog/sensors/chips.c
@@ -105,6 +105,43 @@ int sensors_get_label_and_valid(sensors_chip_name name, int feature, char **labe
  return err;
 }

+void print_ds1621(const sensors_chip_name *name)
+{
+  char *label;
+  double cur,hyst,over;
+  int alarms, valid;
+
+  if (!sensors_get_feature(*name,SENSORS_LM78_ALARMS,&cur)) 
+    alarms = cur + 0.5;
+  else {
+    printf("ERROR: Can't get alarm data!\n");
+    alarms = 0;
+  }
+
+  if (!sensors_get_label_and_valid(*name,SENSORS_DS1621_TEMP,&label,&valid) &&
+      !sensors_get_feature(*name,SENSORS_DS1621_TEMP,&cur) &&
+      !sensors_get_feature(*name,SENSORS_DS1621_TEMP_HYST,&hyst) &&
+      !sensors_get_feature(*name,SENSORS_DS1621_TEMP_OVER,&over))  {
+    if (valid) {
+      print_label(label,10);
+      printf("%6.1f C (high limit: %6.1f C, low limit: %6.1f C)   ",
+             cur,over,hyst);
+      if (alarms & (DS1621_ALARM_TEMP_HIGH | DS1621_ALARM_TEMP_LOW)) {
+        printf("ALARM (");
+        if (alarms & DS1621_ALARM_TEMP_LOW) {
+          printf("LOW");
+        }
+        if (alarms & DS1621_ALARM_TEMP_HIGH)
+          printf("%sHIGH",(alarms & DS1621_ALARM_TEMP_LOW)?",":"");
+        printf(")");
+      }
+      printf("\n");
+    }
+  } else
+    printf("ERROR: Can't get temperature data!\n");
+  free_the_label(&label);
+}
+
 void print_lm75(const sensors_chip_name *name)
 {
  char *label;
--- a/prog/sensors/chips.h
+++ b/prog/sensors/chips.h
@@ -24,6 +24,7 @@

 extern void print_unknown_chip(const sensors_chip_name *name);

+extern void print_ds1621(const sensors_chip_name *name);
 extern void print_mtp008(const sensors_chip_name *name);
 extern void print_lm75(const sensors_chip_name *name);
 extern void print_adm1021(const sensors_chip_name *name);
--- a/prog/sensors/main.c
+++ b/prog/sensors/main.c
@@ -260,6 +260,8 @@ void do_a_print(sensors_chip_name name)
    printf(" ERROR: Can't get adapter or algorithm?!?\n");
  if (do_unknown)
    print_unknown_chip(&name);
+  else if (!strcmp(name.prefix,"ds1621"))
+    print_ds1621(&name);
  else if (!strcmp(name.prefix,"lm75"))
    print_lm75(&name);
  else if (!strcmp(name.prefix,"adm1021") || !strcmp(name.prefix,"max1617") ||