Module smbus.o, many other small changes

git-svn-id: http://lm-sensors.org/svn/lm-sensors/trunk@8 7894878c-1315-0410-8ee3-d5d059ff63e0

20 files changed, 1691 insertions, 62 deletions

diff --git a/CONTRIBUTORS b/CONTRIBUTORS
new file mode 100644
index 00000000..42dd77bb
--- /dev/null
+++ b/CONTRIBUTORS
@@ -0,0 +1,26 @@
+This package could not have been created without the help of many, many people.
+The most notable contributors are listed below.
+
+* Alexander Larsson <alla@lysator.liu.se>
+  Wrote the original lm78 module; lm_sensors version 1 was no more than an
+  extension of this module. He still likes to keep an eye on current
+  developments, but is usually too busy with other things to do much work
+  on them
+* Philip Edelbrock <phil@netroedge.com>
+  Took up the development of the Alex' lm78 module. Responsible for most
+  SMBus code, and many, many other things. He is still one of the main
+  developers of the current package.
+* Frodo Looijaard <frodol@dds.nl>
+  Took up the development of Alex' lm78 module. Large pieces of code were
+  written by him. Designed lm_sensors version 2.
+* William Morgan <wmorgan@cmu.edu>
+  Helped with some patches in lm_sensors version 1. He provided us with
+  the original CVS archive, and even managed to explain to us how to use
+  it.
+
+* Simon Vogl <simon@tk.uni-linz.ac.at>
+  Wrote the new i2c kernel driver. This driver is indispensable for the
+  workings of lm_sensors version 2.
+* Gerd Knorr <kraxel@cs.tu-berlin.de> (?)
+  Designed the i2c structs, which made it possible to use the smbus-is-
+  just-an-i2c-extension approach.
diff --git a/COPYING b/COPYING
new file mode 100644
index 00000000..a43ea212
--- /dev/null
+++ b/COPYING
@@ -0,0 +1,339 @@
+		    GNU GENERAL PUBLIC LICENSE
+		       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.
+                          675 Mass Ave, Cambridge, MA 02139, USA
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+
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+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
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+
+	Appendix: How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) 19yy  <name of author>
+
+    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.
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
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+    Gnomovision version 69, Copyright (C) 19yy name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Library General
+Public License instead of this License.
diff --git a/Makefile b/Makefile
index bd7e1ef7..53a1d2f9 100644
--- a/Makefile
+++ b/Makefile
@@ -1,3 +1,21 @@
+#  Makefile - Makefile for a Linux module for reading sensor data.
+#  Copyright (c) 1998  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.
+
+
 # Uncomment the third line on SMP systems if the magic invocation fails.
 SMP := $(shell if grep -q '^SMP[[:space:]]*=' /usr/src/linux/Makefile; then echo 1; else echo 0; fi)
 #SMP := 0
@@ -12,6 +30,8 @@ MODVER := $(shell if cat /usr/include/linux/config.h /usr/include/linux/autoconf
 # Uncomment the second line if you do not want to compile the included
 # i2c modules. WARNING! If the i2c module version does not match the 
 # smbus/sensor module versions, you will get into severe problems.
+# If you want to use a self-compiled version of the i2c modules, make
+# sure <linux/i2c.h> contains the *correct* i2c header file!
 I2C := 1
 #I2C := 0
 
@@ -45,17 +65,21 @@ INCLUDEDIR := /usr/local/include/linux
 # to do this. 
 
 # The subdirectories we need to build things in 
-MODULES :=
+MODULES := src
 ifeq ($(I2C),1)
-MODULES += i2c
+MODULES += i2c i2c/detect i2c/drivers i2c/eeprom
 endif
 
 # Some often-used commands with default options
 MKDIR := mkdir -p
 RM := rm -f
+CC := gcc
 
 # Determine the default compiler flags
-CFLAGS := -D__KERNEL__ -DMODULE -I. -O2 -fomit-frame-pointer
+# CFLAGS is to create in-kernel object files (modules); EXCFLAGS is to create
+# non-kernel object files (which are linked into executables).
+CFLAGS := -D__KERNEL__ -DMODULE -I. -Ii2c -O2 -fomit-frame-pointer
+EXCFLAGS := -I. -O2 -Ii2c
 
 ifeq ($(SMP),1)
 CFLAGS += -D__SMP__
@@ -64,13 +88,19 @@ endif
 ifeq ($(WARN),1)
 CFLAGS += -Wall -Wstrict-prototypes -Wshadow -Wpointer-arith -Wcast-qual \
           -Wcast-align -Wwrite-strings -Wnested-externs -Winline
+EXCFLAGS += -Wall -Wstrict-prototypes -Wshadow -Wpointer-arith -Wcast-qual \
+            -Wcast-align -Wwrite-strings -Wnested-externs -Winline
 endif
 
 ifeq ($(MODVER),1)
 CFLAGS += -DMODVERSIONS -include /usr/include/linux/modversions.h
 endif
 
-.PHONY: all clean install version package
+ifeq ($(I2C),1)
+CFLAGS += -DI2C
+endif
+
+.PHONY: all clean install version package dep
 
 # Make all the default rule
 all::
@@ -78,18 +108,21 @@ all::
 # Include all makefiles for sub-modules
 include $(patsubst %,%/Module.mk,$(MODULES))
 
+# Making the dependency files - done automatically!
+dep:
 
-all::
+all ::
 
-install::
+install :: all
 
 clean::
 	$(RM) lm_sensors-*
 
-# Create a dependency file. Tricky.
+# Create a dependency file. Tricky. We sed rule puts dir/file.d and dir/file.c
+# in front of the dependency file rule.
 %.d: %.c
-	gcc -M -MG $(CFLAGS) $< | \
-	sed -e 's@ /[^ ]*@@g' -e 's@^\(.*\)\.o:@\1.d \1.o:@' > $@
+	$(CC) -M -MG $(CFLAGS) $< | \
+       	sed -e 's@^\(.*\)\.o:@$*.d $*.o Makefile '`dirname $*.d`/Module.mk':@' > $@
 	
 
 # This is tricky, but it works like a charm. It needs lots of utilities
diff --git a/TODO b/TODO
new file mode 100644
index 00000000..d1ca723d
--- /dev/null
+++ b/TODO
@@ -0,0 +1,5 @@
+Many, many things. Most notably:
+
+* Write s32 smbus_access_i2c in smbus.c
+* Check out whether we can use the dev interface for smbus (like i2c)
+* Write all other modules
diff --git a/doc/design b/doc/design
index 89f2cd3d..35b33d98 100644
--- a/doc/design
+++ b/doc/design
@@ -4,6 +4,8 @@ distribute it, as long as you recognize me as the author, and mark any
 changes you make as being your own, and distribute this notice with it.
 
 Document version 1.0, 19981101.
+                 1.1, 19981111.
+                 1.2, 19981118.
 
 
 Object oriented approach
@@ -130,6 +132,7 @@ Unites SMBus adapters and ISA adapters.
 smbus.o
 Main SMBus handling
 Unites I2C adapters and SMBus hosts (like the PIIX4)
+Defines smbus_algorithm
 
   piix4.o
   SMBus adapter driver for the PIIX4 SMBus host.
@@ -331,9 +334,13 @@ means there must be some way of selecting which of the many possible adapters
 is in fact *the* SMBus. For now, I will ignore this problem. Later on,
 we can add a hook somewhere in the i2c module to help us decide this.
 
+This module consists in fact of two separate parts: first of all, it extends
+all i2c structs to accomodate the new smbus fields. Second, it defines a
+new algorithm (smbus_algorithm), that will be used by all non-i2c adapters.
 
-A driver, client and adapter
--------------------
+
+A driver, client and algorithm
+------------------------------
 
 We will not need to extend i2c_driver, i2c_client or i2c_adapter. This means
 that struct smbus_driver is exactly the same as struct i2c_driver, and 
@@ -346,30 +353,34 @@ partially supported by the i2c module. We will ignore this issue for
 now.
 
 
-An algorithm
+An adapter
 ------------
 
-struct smbus_algorithm {
+struct smbus_adapter {
   char name[32];
   unsigned int id;
-  int (* master_xfer) (struct smbus_adapter *adap, struct smbus_msg msgs[],
-                       int num);
-  int (* slave_send) (struct smbus_adapter *,char *, int);
-  int (* slave_recv) (struct smbus_adapter *,char *, int);
-  int (* algo_control) (struct smbus_adapter *, unsigned int, unsigned long);
-  int (* client_register) (struct smbus_client *);
-  int (* client_unregister) (struct smbus_client *);
+  struct smbus_algorithm *algo;
+  void *data;
+#ifdef SPINLOCK
+  spinlock_t lock;
+  unsigned long lockflags;
+#else
+  struct semaphore lock;
+#endif
+  unsigned int flags;
+  struct smbus_client *clients[I2C_CLIENT_MAX];
+  int client_count;
+  int timeout;
+  int retries;
 
-  int (* smbus_access) (struct smbus_adapter *, __u8 addr, char read_write,
+  /* Here ended i2c_algorithm */
+  s32 (* smbus_access) (__u8 addr, char read_write,
                         __u8 command, int size, union smbus_data * data);
 }
 
-
 A description of the above struct:
-  smbus_access: A function to access the SMBus. If the algorithm describes
-      a i2c bus, it will use master_xfer to simulate this operation. In
-      case of a PIIX4, master_xfer, slave_send and slave_recv will not be
-      implemented.
+  smbus_access: A function to access the SMBus. It is only used for non-i2c
+      smbus adapters.
 
 
 Access functions
diff --git a/i2c/MODIFICATIONS b/i2c/MODIFICATIONS
new file mode 100644
index 00000000..9c118cea
--- /dev/null
+++ b/i2c/MODIFICATIONS
@@ -0,0 +1,33 @@
+This is a list of modifications between the stock i2c code as distributed
+by Simon Vogl, and the code included in and beneath this directory. None
+of these changes are important; you can still use a self-compiled version
+of the i2c code and not compile the version in here.
+
+* rscid declarations are changed
+  This is an unfortunate interaction between our CVS server and Simon's
+  RCS (CVS?) server. As these ids do not seem to be accessed anywhere,
+  there should be no change in the final object code
+
+* Log entries are added
+  Another RCS/CVS side effect. Our logs are sometimes put in the source
+  code. As they are just comments, they will do no harm.
+
+* EXPORT_SYMBOL declarations removed
+  They only work if you use the Linux source tree Makefiles. As we want to
+  use our own Makefile, we have removed them. This should have almost no
+  influence on the resulting object code; a few more functions may be
+  exported, but this should do no harm.
+
+* bit-mb: Linux 2.0.x fixes
+  Some small changes to make this file compile with 2.0 kernels. These
+  changes will probably be included in the next i2c version.
+
+* New file: Module.mk
+  The Makefile fragment we use to compile the files in this directory.
+
+* New file: MODIFICATIONS
+  The file you are reading right now.
+
+* Removed files: object files and executables
+  Everywhere, remakeable files are removed, to keep the source distribution
+  small and lean.
diff --git a/i2c/Module.mk b/i2c/Module.mk
index 3d82d26d..594670b5 100644
--- a/i2c/Module.mk
+++ b/i2c/Module.mk
@@ -1,20 +1,39 @@
+#  Module.mk - Makefile for a Linux module for reading sensor data.
+#  Copyright (c) 1998  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.
+
 # Note that MODULE_DIR (the directory in which this file resides) is a
 # 'simply expanded variable'. That means that its value is substituted
 # verbatim in the rules, until it is redefined. 
 MODULE_DIR := i2c
 
-TARGETS := $(MODULE_DIR)/i2c-core.o  $(MODULE_DIR)/algo-bit.o \
-           $(MODULE_DIR)/i2c-dev.o   $(MODULE_DIR)/bit-lp.o \
-           $(MODULE_DIR)/bit-velle.o $(MODULE_DIR)/bit-mb.o
+# Regrettably, even 'simply expanded variables' will not put their currently
+# defined value verbatim into the command-list of rules...
+I2CTARGETS := $(MODULE_DIR)/i2c-core.o  $(MODULE_DIR)/algo-bit.o \
+              $(MODULE_DIR)/i2c-dev.o   $(MODULE_DIR)/bit-lp.o \
+              $(MODULE_DIR)/bit-velle.o $(MODULE_DIR)/bit-mb.o
 
 # Include all dependency files
-include $(TARGETS:.o=.d)
+include $(I2CTARGETS:.o=.d)
 
-all :: $(TARGETS)
+all :: $(I2CTARGETS)
 
-install :: $(TARGETS)
+install :: 
 	$(MKDIR) $(MODDIR)
-	install -o root -g root -m 644 $(TARGETS) $(MODDIR)
+	install -o root -g root -m 644 $(I2CTARGETS) $(MODDIR)
 
 clean ::
-	$(RM) $(TARGETS) $(TARGETS:.o=.d)
+	$(RM) $(I2CTARGETS) $(I2CTARGETS:.o=.d)
diff --git a/i2c/algo-bit.c b/i2c/algo-bit.c
index 33c2a70b..a336b330 100644
--- a/i2c/algo-bit.c
+++ b/i2c/algo-bit.c
@@ -17,7 +17,7 @@
     along with this program; if not, write to the Free Software
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.		     */
 /* ------------------------------------------------------------------------- */
-static char alg_rcsid[] = "$Id: algo-bit.c,v 1.1 1998/11/02 20:29:27 frodo Exp $";
+static char alg_rcsid[] = "$Id: algo-bit.c,v 1.2 1998/11/03 03:48:44 phil Exp $";
 
 #include <linux/kernel.h>
 #include <linux/module.h>
@@ -638,10 +638,6 @@ MODULE_PARM_DESC(bit_test, "Test the lines of the bus to see if it is stuck");
 MODULE_PARM_DESC(bit_scan, "Scan for active chips on the bus");
 MODULE_PARM_DESC(i2c_debug,"debug level - 0 off; 1 normal; 2,3 more verbose; 9 bit-protocol");
 
-#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,1,0))
-EXPORT_SYMBOL(i2c_bit_add_bus);
-EXPORT_SYMBOL(i2c_bit_del_bus);
-#endif
 
 int init_module(void) 
 {
diff --git a/i2c/bit-lp.c b/i2c/bit-lp.c
index 55c438a5..04251be7 100644
--- a/i2c/bit-lp.c
+++ b/i2c/bit-lp.c
@@ -17,7 +17,7 @@
     along with this program; if not, write to the Free Software
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.		     */
 /* ------------------------------------------------------------------------- */
-static char rcsid[] = "$Id: bit-lp.c,v 1.5 1998/09/28 06:45:38 i2c Exp i2c $";
+static char rcsid[] = "$Id: bit-lp.c,v 1.1 1998/11/02 20:29:27 frodo Exp $";
 /* ------------------------------------------------------------------------- */
 
 #include <linux/kernel.h>
@@ -151,8 +151,6 @@ MODULE_DESCRIPTION("I2C-Bus adapter routines for Philips parallel port adapter")
 
 MODULE_PARM(base, "i");
 
-EXPORT_NO_SYMBOLS;
-
 int init_module(void) 
 {
 	if (base==0) {
diff --git a/i2c/detect/Module.mk b/i2c/detect/Module.mk
new file mode 100644
index 00000000..fbbd8fa8
--- /dev/null
+++ b/i2c/detect/Module.mk
@@ -0,0 +1,53 @@
+#  Module.mk - Makefile for a Linux module for reading sensor data.
+#  Copyright (c) 1998  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.
+
+# Note that MODULE_DIR (the directory in which this file resides) is a
+# 'simply expanded variable'. That means that its value is substituted
+# verbatim in the rules, until it is redefined. 
+MODULE_DIR := i2c/detect
+
+# Regrettably, even 'simply expanded variables' will not put their currently
+# defined value verbatim into the command-list of rules...
+I2CDETECTTARGETS := $(MODULE_DIR)/detect
+I2CDETECTSOURCES := $(MODULE_DIR)/detect.c
+
+# Include all dependency files
+include $(I2CDETECTSOURCES:.c=.d)
+
+all :: $(I2CDETECTTARGETS)
+
+# No install rule
+
+clean ::
+	$(RM) $(I2CDETECTSOURCES:.c=.d) $(I2CDETECTSOURCES:.c=.o) \
+	      $(I2CDETECTTARGETS)
+
+# The targets
+$(MODULE_DIR)/detect: $(MODULE_DIR)/detect.o
+
+
+# Oops, we need to use EXCFLAGS instead of CFLAGS... And we have to deal with
+# an executable. Ugly code approaching... :-)
+
+$(I2CDETECTSOURCES:.c=.o):
+	$(CC) $(EXCFLAGS) -c $(@:.o=.c) -o $@
+
+$(I2CDETECTSOURCES:.c=.d):
+	$(CC) -M -MG $(EXCFLAGS) $(@:.d=.c) | \
+	sed -e \
+        's@^\(.*\)\.o:@$@ $(@:.d=.o) Makefile '`dirname $@`/Module.mk':@' > $@
+
diff --git a/i2c/drivers/Module.mk b/i2c/drivers/Module.mk
new file mode 100644
index 00000000..23be9f68
--- /dev/null
+++ b/i2c/drivers/Module.mk
@@ -0,0 +1,37 @@
+#  Module.mk - Makefile for a Linux module for reading sensor data.
+#  Copyright (c) 1998  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.
+
+# Note that MODULE_DIR (the directory in which this file resides) is a
+# 'simply expanded variable'. That means that its value is substituted
+# verbatim in the rules, until it is redefined. 
+MODULE_DIR := i2c/drivers
+
+# Regrettably, even 'simply expanded variables' will not put their currently
+# defined value verbatim into the command-list of rules...
+I2CDRIVERTARGETS := $(MODULE_DIR)/eeprom.o  
+
+# Include all dependency files
+include $(I2CDRIVERTARGETS:.o=.d)
+
+all :: $(I2CDRIVERTARGETS)
+
+install :: 
+	$(MKDIR) $(MODDIR)
+	install -o root -g root -m 644 $(I2CDRIVERTARGETS) $(MODDIR)
+
+clean ::
+	$(RM) $(I2CDRIVERTARGETS) $(I2CDRIVERTARGETS:.o=.d)
diff --git a/i2c/eeprom/Module.mk b/i2c/eeprom/Module.mk
new file mode 100644
index 00000000..791fb913
--- /dev/null
+++ b/i2c/eeprom/Module.mk
@@ -0,0 +1,53 @@
+#  Module.mk - Makefile for a Linux module for reading sensor data.
+#  Copyright (c) 1998  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.
+
+# Note that MODULE_DIR (the directory in which this file resides) is a
+# 'simply expanded variable'. That means that its value is substituted
+# verbatim in the rules, until it is redefined. 
+MODULE_DIR := i2c/eeprom
+
+# Regrettably, even 'simply expanded variables' will not put their currently
+# defined value verbatim into the command-list of rules...
+I2CEEPROMTARGETS := $(MODULE_DIR)/eeprom
+I2CEEPROMSOURCES := $(MODULE_DIR)/eeprom.c
+
+# Include all dependency files
+include $(I2CEEPROMSOURCES:.c=.d)
+
+all :: $(I2CEEPROMTARGETS)
+
+# No install rule
+
+clean ::
+	$(RM) $(I2CEEPROMSOURCES:.c=.d) $(I2CEEPROMSOURCES:.c=.o) \
+	      $(I2CEEPROMTARGETS)
+
+# The targets
+$(MODULE_DIR)/eeprom: $(MODULE_DIR)/eeprom.o
+
+
+# Oops, we need to use EXCFLAGS instead of CFLAGS... And we have to deal with
+# an executable. Ugly code approaching... :-)
+
+$(I2CEEPROMSOURCES:.c=.o):
+	$(CC) $(EXCFLAGS) -c $(@:.o=.c) -o $@
+
+$(I2CEEPROMSOURCES:.c=.d):
+	$(CC) -M -MG $(EXCFLAGS) $(@:.d=.c) | \
+	sed -e \
+        's@^\(.*\)\.o:@$@ $(@:.d=.o) Makefile '`dirname $@`/Module.mk':@' > $@
+
diff --git a/i2c/i2c-core.c b/i2c/i2c-core.c
index 0ee5bd1e..d2aa4e52 100644
--- a/i2c/i2c-core.c
+++ b/i2c/i2c-core.c
@@ -17,7 +17,7 @@
     along with this program; if not, write to the Free Software
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.		     */
 /* ------------------------------------------------------------------------- */
-#define RCSID "$Id: i2c-core.c,v 1.1 1998/11/02 20:29:27 frodo Exp $"
+#define RCSID "$Id: i2c-core.c,v 1.2 1998/11/03 03:48:44 phil Exp $"
 /* ------------------------------------------------------------------------- */
 
 #include <linux/module.h>
@@ -441,22 +441,6 @@ MODULE_DESCRIPTION("I2C-Bus main module");
 MODULE_PARM(i2c_debug, "i");
 MODULE_PARM_DESC(i2c_debug,"debug level");
 
-#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,1,0))
-EXPORT_SYMBOL(i2c_add_algorithm);
-EXPORT_SYMBOL(i2c_del_algorithm);
-EXPORT_SYMBOL(i2c_add_adapter);
-EXPORT_SYMBOL(i2c_del_adapter);
-EXPORT_SYMBOL(i2c_add_driver);
-EXPORT_SYMBOL(i2c_del_driver);
-EXPORT_SYMBOL(i2c_attach_client);
-EXPORT_SYMBOL(i2c_detach_client);
-
-EXPORT_SYMBOL(i2c_master_send);
-EXPORT_SYMBOL(i2c_master_recv);
-EXPORT_SYMBOL(i2c_control);
-EXPORT_SYMBOL(i2c_transfer);
-#endif
-
 int init_module(void) 
 {
 	return i2c_init();
diff --git a/i2c/i2c-dev.c b/i2c/i2c-dev.c
index 44d76d6d..f823bd71 100644
--- a/i2c/i2c-dev.c
+++ b/i2c/i2c-dev.c
@@ -17,7 +17,7 @@
     along with this program; if not, write to the Free Software
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.		     */
 /* ------------------------------------------------------------------------- */
-#define RCSID "$Id: i2c-dev.c,v 1.6 1998/09/28 06:45:38 i2c Exp i2c $"
+#define RCSID "$Id: i2c-dev.c,v 1.1 1998/11/02 20:29:27 frodo Exp $"
 /* ------------------------------------------------------------------------- */
 
 #include <linux/kernel.h>
@@ -337,8 +337,6 @@ struct i2c_driver driver = {
 MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>");
 MODULE_DESCRIPTION("I2C-Bus character device interface");
 
-EXPORT_NO_SYMBOLS;
-
 int init_module(void) 
 {
 	if (register_chrdev(I2C_MAJOR,"i2c",&i2c_fops)) {
diff --git a/kernel/Module.mk b/kernel/Module.mk
new file mode 100644
index 00000000..2495e5aa
--- /dev/null
+++ b/kernel/Module.mk
@@ -0,0 +1,37 @@
+#  Module.mk - Makefile for a Linux module for reading sensor data.
+#  Copyright (c) 1998  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.
+
+# Note that MODULE_DIR (the directory in which this file resides) is a
+# 'simply expanded variable'. That means that its value is substituted
+# verbatim in the rules, until it is redefined. 
+MODULE_DIR := src
+
+# Regrettably, even 'simply expanded variables' will not put their currently
+# defined value verbatim into the command-list of rules...
+SRCTARGETS := $(MODULE_DIR)/smbus.o 
+
+# Include all dependency files
+include $(SRCTARGETS:.o=.d)
+
+all :: $(SRCTARGETS)
+
+install ::
+	$(MKDIR) $(MODDIR)
+	install -o root -g root -m 644 $(SRCTARGETS) $(MODDIR)
+
+clean ::
+	$(RM) $(SRCTARGETS) $(SRCTARGETS:.o=.d)
diff --git a/kernel/include/smbus.h b/kernel/include/smbus.h
new file mode 100644
index 00000000..bbe2334b
--- /dev/null
+++ b/kernel/include/smbus.h
@@ -0,0 +1,270 @@
+/*
+    smbus.h - A Linux module for reading sensor data.
+    Copyright (c) 1998  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.
+*/
+
+#ifndef SENSORS_SMBUS_H
+#define SENSORS_SMBUS_H
+
+/* This file must interface with Simon Vogl's i2c driver. Version 19981006 is
+   OK, earlier versions are not; later versions will probably give problems
+   too. 
+*/
+#ifdef I2C
+#include "i2c/i2c.h"
+#else /* def I2C */
+#include <linux/i2c.h>
+#endif /* def I2C */
+
+#include <asm/types.h>
+
+/* SPINLOCK is defined in i2c.h. */
+#ifdef SPINLOCK
+#include <asm/spinlock.h>
+#else
+#include <asm/semaphore.h>
+#endif
+
+/* Declarations, to keep the compiler happy */
+struct smbus_driver;
+struct smbus_client;
+struct smbus_algorithm;
+struct smbus_adapter;
+union smbus_data;
+
+/* A driver tells us how we should handle a specific kind of chip.
+   A specific instance of such a chip is called a client.  
+   This structure is essentially the same as i2c_driver. */
+struct smbus_driver {
+  char name[32];
+  int id;
+  unsigned int flags;
+  int (* attach_adapter) (struct smbus_adapter *);
+  int (* detach_client) (struct smbus_client *);
+  int (* command) (struct smbus_client *, unsigned int cmd, void *arg);
+  void (* inc_use) (struct smbus_client *);
+  void (* dec_use) (struct smbus_client *);
+};
+
+/* A client is a specifc instance of a chip: for each detected chip, there will
+   be a client. Its operation is controlled by a driver.
+   This structure is essentially the same as i2c_client. */
+struct smbus_client {
+  char name[32];
+  int id;
+  unsigned int flags;
+  unsigned char addr;
+  struct smbus_adapter *adapter;
+  struct smbus_driver *driver;
+  void *data;
+};
+
+/* An algorithm describes how a certain class of busses can be accessed. 
+   A specific instance of sucj a bus is called an adapter. 
+   This structure is essentially the same as i2c_adapter. */
+struct smbus_algorithm {
+  char name[32];
+  unsigned int id;
+  int (* master_xfer) (struct smbus_adapter *adap, struct i2c_msg msgs[],
+                       int num);
+  int (* slave_send) (struct smbus_adapter *,char *, int);
+  int (* slave_recv) (struct smbus_adapter *,char *, int);
+  int (* algo_control) (struct smbus_adapter *, unsigned int, unsigned long);
+  int (* client_register) (struct smbus_client *);
+  int (* client_unregister) (struct smbus_client *);
+};
+
+/* An adapter is a specifc instance of a bus: for each detected bus, there will
+   be an adapter. Its operation is controlled by an algorithm. 
+   SPINLOCK must be the same as declared in i2c.h.
+   This structure is an extension of i2c_algorithm. */
+struct smbus_adapter {
+  char name[32];
+  unsigned int id;
+  struct smbus_algorithm *algo;
+  void *data;
+#ifdef SPINLOCK
+  spinlock_t lock;
+  unsigned long lockflags;
+#else
+  struct semaphore lock;
+#endif
+  unsigned int flags;
+  struct smbus_client *clients[I2C_CLIENT_MAX];
+  int client_count;
+  int timeout;
+  int retries;
+
+  /* Here ended i2c_algorithm */
+  s32 (* smbus_access) (__u8 addr, char read_write,
+                        __u8 command, int size, union smbus_data * data);
+};
+
+/* We need to mark SMBus algorithms in the algorithm structure. 
+   Note that any and all adapters using a non-i2c driver use in this
+   setup ALGO_SMBUS. Adapters define their own smbus access routine. 
+   This also means that adapter->smbus_access is only available if
+   this flag is set! */
+#define ALGO_SMBUS 0x40000
+
+/* This union is used within smbus_access routines */
+union smbus_data { 
+        __u8 byte;
+        __u16 word;
+        __u8 block[32];
+};
+
+/* smbus_access read or write markers */
+#define SMBUS_READ      1
+#define SMBUS_WRITE     0
+
+/* SMBus transaction types (size parameter in the above functions) 
+   Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
+#define SMBUS_QUICK      0
+#define SMBUS_BYTE       1
+#define SMBUS_BYTE_DATA  2 
+#define SMBUS_WORD_DATA  3
+#define SMBUS_PROC_CALL  4
+#define SMBUS_BLOCK_DATA 5
+
+/* Declare an algorithm structure. All SMBus derived adapters should use this
+   algorithm! */
+extern struct smbus_algorithm smbus_algorithm;
+
+/* This is the very generalized SMBus access routine. You probably do not
+   want to use this, though; one of the functions below may be much easier,
+   and probably just as fast. */
+extern s32 smbus_access (struct smbus_adapter * adapter, u8 addr, 
+                         char read_write, u8 command, int size,
+                         union smbus_data * data);
+
+/* Now follow the 'nice' access routines. These also document the calling
+   conventions of smbus_access. */
+
+extern inline s32 smbus_write_quick(struct smbus_adapter * adapter, u8 addr, 
+                                    u8 value)
+{
+  return smbus_access(adapter,addr,value,0,SMBUS_QUICK,NULL);
+}
+
+extern inline s32 smbus_read_byte(struct smbus_adapter * adapter,u8 addr)
+{
+  union smbus_data data;
+  if (smbus_access(adapter,addr,SMBUS_READ,0,SMBUS_BYTE,&data))
+    return -1;
+  else
+    return data.byte;
+}
+
+extern inline s32 smbus_write_byte(struct smbus_adapter * adapter, u8 addr, 
+                                   u8 value)
+{
+  return smbus_access(adapter,addr,SMBUS_WRITE,value, SMBUS_BYTE,NULL);
+}
+
+extern inline s32 smbus_read_byte_data(struct smbus_adapter * adapter,
+                                       u8 addr, u8 command)
+{
+  union smbus_data data;
+  if (smbus_access(adapter,addr,SMBUS_READ,command,SMBUS_BYTE_DATA,&data))
+    return -1;
+  else
+    return data.byte;
+}
+
+extern inline s32 smbus_write_byte_data(struct smbus_adapter * adapter,
+                                        u8 addr, u8 command, u8 value)
+{
+  union smbus_data data;
+  data.byte = value;
+  return smbus_access(adapter,addr,SMBUS_WRITE,command,SMBUS_BYTE_DATA,&data);
+}
+
+extern inline s32 smbus_read_word_data(struct smbus_adapter * adapter,
+                                       u8 addr, u8 command)
+{
+  union smbus_data data;
+  if (smbus_access(adapter,addr,SMBUS_READ,command,SMBUS_WORD_DATA,&data))
+    return -1;
+  else
+    return data.word;
+}
+
+extern inline s32 smbus_write_word_data(struct smbus_adapter * adapter,
+                                        u8 addr, u8 command, u16 value)
+{
+  union smbus_data data;
+  data.word = value;
+  return smbus_access(adapter,addr,SMBUS_WRITE,command,SMBUS_WORD_DATA,&data);
+}
+
+extern inline s32 smbus_process_call(struct smbus_adapter * adapter,
+                                     u8 addr, u8 command, u16 value)
+{
+  union smbus_data data;
+  data.word = value;
+  if (smbus_access(adapter,addr,SMBUS_WRITE,command,SMBUS_PROC_CALL,&data))
+    return -1;
+  else
+    return data.word;
+}
+
+/* Returns the number of read bytes */
+extern inline s32 smbus_read_block_data(struct smbus_adapter * adapter,
+                                        u8 addr, u8 command, u8 *values)
+{
+  union smbus_data data;
+  int i;
+  if (smbus_access(adapter,addr,SMBUS_READ,command,SMBUS_BLOCK_DATA,&data))
+    return -1;
+  else {
+    for (i = 1; i <= data.block[0]; i++)
+      values[i-1] = data.block[i];
+    return data.block[0];
+  }
+}
+
+extern inline int smbus_write_block_data(struct smbus_adapter * adapter,
+                                         u8 addr, u8 command, u8 length,
+                                         u8 *values)
+{
+  union smbus_data data;
+  int i;
+  if (length > 32)
+    length = 32;
+  for (i = 1; i <= length; i++)
+    data.block[i] = values[i-1];
+  data.block[0] = length;
+  return smbus_access(adapter,addr,SMBUS_WRITE,command,SMBUS_BLOCK_DATA,&data);
+}
+
+/* Next: define SMBus variants of registering. */
+extern int smbus_add_algorithm(struct smbus_algorithm *algorithm);
+extern int smbus_del_algorithm(struct smbus_algorithm *algorithm);
+
+extern int smbus_add_adapter(struct smbus_adapter *adapter);
+extern int smbus_del_adapter(struct smbus_adapter *adapter);
+
+extern int smbus_add_driver(struct smbus_driver *driver);
+extern int smbus_del_driver(struct smbus_driver *driver);
+
+extern int smbus_attach_client(struct smbus_client *client);
+extern int smbus_detach_client(struct smbus_client *client);
+
+
+#endif /* ndef SENSORS_SMBUS_H */
+
diff --git a/kernel/smbus.c b/kernel/smbus.c
new file mode 100644
index 00000000..ab592806
--- /dev/null
+++ b/kernel/smbus.c
@@ -0,0 +1,215 @@
+/*
+    smbus.c - A Linux module for reading sensor data.
+    Copyright (c) 1998  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.
+*/
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include "smbus.h"
+
+static s32 smbus_access_i2c (struct smbus_adapter * adapter, u8 addr,
+                             char read_write, u8 command, int size,
+                             union smbus_data * data);
+
+static int smbus_master_xfer (struct smbus_adapter *adap,
+                              struct i2c_msg msgs[], int num);
+static int smbus_slave_send (struct smbus_adapter *adap, char *data, int len);
+static int smbus_slave_recv (struct smbus_adapter *adap, char *data, int len);
+static int smbus_algo_control (struct smbus_adapter *adap, unsigned int cmd, 
+                               unsigned long arg);
+static int smbus_client_register (struct smbus_client *client);
+static int smbus_client_unregister (struct smbus_client *client);
+
+static int smbus_init(void);
+static int smbus_cleanup(void);
+
+#ifdef MODULE
+extern int init_module(void);
+extern int cleanup_module(void);
+#endif /* MODULE */
+
+/* This is the actual algorithm we define */
+struct smbus_algorithm smbus_algorithm = {
+  /* name */		"Non-I2C SMBus adapter",
+  /* id */		ALGO_SMBUS,
+  /* master_xfer */	&smbus_master_xfer,
+  /* slave_send */	&smbus_slave_send,
+  /* slave_rcv */	&smbus_slave_recv,
+  /* algo_control */	&smbus_algo_control,
+  /* client_register */ &smbus_client_register,
+  /* client_unregister*/&smbus_client_unregister
+};
+
+
+/* OK, so you want to access a bus using the SMBus protocols. Well, it either
+   is registered as a SMBus-only adapter (like the PIIX4), or we need to
+   simulate the SMBus commands using the i2c access routines. */
+s32 smbus_access (struct smbus_adapter * adapter, u8 addr, char read_write,
+                  u8 command, int size, union smbus_data * data)
+{
+  if (adapter->id & ALGO_SMBUS) 
+    return adapter->smbus_access(addr,read_write,command,size,data);
+  else
+    return smbus_access_i2c(adapter,addr,read_write,command,size,data);
+}
+  
+/* Simulate a SMBus command using the i2c protocol 
+   No checking of paramters is done!
+   For SMBUS_QUICK: Use addr, read_write 
+   For SMBUS_BYTE: Use addr, read_write, command 
+   ....  */
+s32 smbus_access_i2c(struct smbus_adapter * adapter, u8 addr, char read_write,
+                     u8 command, int size, union smbus_data * data)
+{
+  /* So we need to generate a series of msgs */
+  struct i2c_msg msg[2];
+  char msgbuf0[2];
+  char msgbuf1[32];
+  msg[0].addr = addr;
+  msg[0].flags = read_write;
+  msg[0].len = 0;
+  msg[0].buf = msgbuf0;
+  /* WHATEVER */
+}
+
+/* Algorithm master_xfer call-back implementation. Can't do that... */
+int smbus_master_xfer (struct smbus_adapter *adap, struct i2c_msg msgs[], 
+                       int num)
+{
+  printk("smbus_master_xfer called for adapter `%s' "
+         "(no i2c level access possible!)\n",
+         adap->name);
+  return 0;
+}
+
+/* Algorithm slave_send call-back implementation. Can't do that... */
+int smbus_slave_send (struct smbus_adapter *adap, char *data, int len)
+{
+  printk("smbus_slave_send called for adapter `%s' "
+         "(no i2c level access possible!)\n",
+         adap->name);
+  return 0;
+}
+
+/* Algorithm slave_recv call-back implementation. Can't do that... */
+int smbus_slave_recv (struct smbus_adapter *adap, char *data, int len)
+{
+  printk("smbus_slave_recv called for adapter `%s' "
+         "(no i2c level access possible!)\n",
+         adap->name);
+  return 0;
+}
+
+/* Here we can put additional calls to modify the workings of the algorithm.
+   But right now, there is no need for that. */
+int smbus_algo_control (struct smbus_adapter *adap, unsigned int cmd, 
+                         unsigned long arg)
+{
+  return 0;
+}
+
+/* Ehm... This is called when a client is registered to an adapter. We could
+   do all kinds of neat stuff here like, ehm - returning success? */
+int smbus_client_register (struct smbus_client *client)
+{
+  return 0;
+}
+  
+int smbus_client_unregister (struct smbus_client *client)
+{
+  return 0;
+}
+
+/* Next: define SMBus variants of registering. Very boring. To make it possible
+   to change these definitions in the future without recompiling all modules,
+   we do not define them as inline. */
+int smbus_add_algorithm(struct smbus_algorithm *algorithm)
+{
+  return i2c_add_algorithm( (struct i2c_algorithm *) algorithm);
+}
+
+int smbus_del_algorithm(struct smbus_algorithm *algorithm)
+{
+  return i2c_del_algorithm( (struct i2c_algorithm *) algorithm);
+}
+
+int smbus_add_adapter(struct smbus_adapter *adapter)
+{
+  return i2c_add_adapter( (struct i2c_adapter *) adapter);
+}
+
+int smbus_del_adapter(struct smbus_adapter *adapter)
+{
+  return i2c_del_adapter( (struct i2c_adapter *) adapter);
+}
+
+int smbus_add_driver(struct smbus_driver *driver)
+{
+  return i2c_add_driver( (struct i2c_driver *) driver);
+}
+
+int smbus_del_driver(struct smbus_driver *driver)
+{
+  return i2c_del_driver( (struct i2c_driver *) driver);
+}
+
+int smbus_attach_client(struct smbus_client *client)
+{
+  return i2c_attach_client( (struct i2c_client *) client);
+}
+
+int smbus_detach_client(struct smbus_client *client)
+{
+  return i2c_detach_client( (struct i2c_client *) client);
+}
+
+int smbus_init(void)
+{
+  int res;
+  if ((res = smbus_add_algorithm(&smbus_algorithm)))
+    printk("Module smbus.o not inserted!\n");
+  else
+    printk("smbus.o initialized");
+  return res;
+}
+
+int smbus_cleanup(void)
+{
+  int res;
+  if ((res = smbus_del_algorithm(&smbus_algorithm)))
+    printk("Module smbus.o could not be removed cleanly!\n");
+  return res;
+}
+
+/* OK, this will for now _only_ compile as a module, but this is neat for
+   later, if we want to compile it straight into the kernel */
+#ifdef MODULE
+
+MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
+MODULE_DESCRIPTION("System Management Bus (SMBus) access");
+
+int init_module(void)
+{
+  return smbus_init();
+}
+
+int cleanup_module(void)
+{
+  return smbus_cleanup();
+}
+
+#endif /* MODULE */
diff --git a/src/Module.mk b/src/Module.mk
new file mode 100644
index 00000000..2495e5aa
--- /dev/null
+++ b/src/Module.mk
@@ -0,0 +1,37 @@
+#  Module.mk - Makefile for a Linux module for reading sensor data.
+#  Copyright (c) 1998  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.
+
+# Note that MODULE_DIR (the directory in which this file resides) is a
+# 'simply expanded variable'. That means that its value is substituted
+# verbatim in the rules, until it is redefined. 
+MODULE_DIR := src
+
+# Regrettably, even 'simply expanded variables' will not put their currently
+# defined value verbatim into the command-list of rules...
+SRCTARGETS := $(MODULE_DIR)/smbus.o 
+
+# Include all dependency files
+include $(SRCTARGETS:.o=.d)
+
+all :: $(SRCTARGETS)
+
+install ::
+	$(MKDIR) $(MODDIR)
+	install -o root -g root -m 644 $(SRCTARGETS) $(MODDIR)
+
+clean ::
+	$(RM) $(SRCTARGETS) $(SRCTARGETS:.o=.d)
diff --git a/src/smbus.c b/src/smbus.c
new file mode 100644
index 00000000..ab592806
--- /dev/null
+++ b/src/smbus.c
@@ -0,0 +1,215 @@
+/*
+    smbus.c - A Linux module for reading sensor data.
+    Copyright (c) 1998  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.
+*/
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include "smbus.h"
+
+static s32 smbus_access_i2c (struct smbus_adapter * adapter, u8 addr,
+                             char read_write, u8 command, int size,
+                             union smbus_data * data);
+
+static int smbus_master_xfer (struct smbus_adapter *adap,
+                              struct i2c_msg msgs[], int num);
+static int smbus_slave_send (struct smbus_adapter *adap, char *data, int len);
+static int smbus_slave_recv (struct smbus_adapter *adap, char *data, int len);
+static int smbus_algo_control (struct smbus_adapter *adap, unsigned int cmd, 
+                               unsigned long arg);
+static int smbus_client_register (struct smbus_client *client);
+static int smbus_client_unregister (struct smbus_client *client);
+
+static int smbus_init(void);
+static int smbus_cleanup(void);
+
+#ifdef MODULE
+extern int init_module(void);
+extern int cleanup_module(void);
+#endif /* MODULE */
+
+/* This is the actual algorithm we define */
+struct smbus_algorithm smbus_algorithm = {
+  /* name */		"Non-I2C SMBus adapter",
+  /* id */		ALGO_SMBUS,
+  /* master_xfer */	&smbus_master_xfer,
+  /* slave_send */	&smbus_slave_send,
+  /* slave_rcv */	&smbus_slave_recv,
+  /* algo_control */	&smbus_algo_control,
+  /* client_register */ &smbus_client_register,
+  /* client_unregister*/&smbus_client_unregister
+};
+
+
+/* OK, so you want to access a bus using the SMBus protocols. Well, it either
+   is registered as a SMBus-only adapter (like the PIIX4), or we need to
+   simulate the SMBus commands using the i2c access routines. */
+s32 smbus_access (struct smbus_adapter * adapter, u8 addr, char read_write,
+                  u8 command, int size, union smbus_data * data)
+{
+  if (adapter->id & ALGO_SMBUS) 
+    return adapter->smbus_access(addr,read_write,command,size,data);
+  else
+    return smbus_access_i2c(adapter,addr,read_write,command,size,data);
+}
+  
+/* Simulate a SMBus command using the i2c protocol 
+   No checking of paramters is done!
+   For SMBUS_QUICK: Use addr, read_write 
+   For SMBUS_BYTE: Use addr, read_write, command 
+   ....  */
+s32 smbus_access_i2c(struct smbus_adapter * adapter, u8 addr, char read_write,
+                     u8 command, int size, union smbus_data * data)
+{
+  /* So we need to generate a series of msgs */
+  struct i2c_msg msg[2];
+  char msgbuf0[2];
+  char msgbuf1[32];
+  msg[0].addr = addr;
+  msg[0].flags = read_write;
+  msg[0].len = 0;
+  msg[0].buf = msgbuf0;
+  /* WHATEVER */
+}
+
+/* Algorithm master_xfer call-back implementation. Can't do that... */
+int smbus_master_xfer (struct smbus_adapter *adap, struct i2c_msg msgs[], 
+                       int num)
+{
+  printk("smbus_master_xfer called for adapter `%s' "
+         "(no i2c level access possible!)\n",
+         adap->name);
+  return 0;
+}
+
+/* Algorithm slave_send call-back implementation. Can't do that... */
+int smbus_slave_send (struct smbus_adapter *adap, char *data, int len)
+{
+  printk("smbus_slave_send called for adapter `%s' "
+         "(no i2c level access possible!)\n",
+         adap->name);
+  return 0;
+}
+
+/* Algorithm slave_recv call-back implementation. Can't do that... */
+int smbus_slave_recv (struct smbus_adapter *adap, char *data, int len)
+{
+  printk("smbus_slave_recv called for adapter `%s' "
+         "(no i2c level access possible!)\n",
+         adap->name);
+  return 0;
+}
+
+/* Here we can put additional calls to modify the workings of the algorithm.
+   But right now, there is no need for that. */
+int smbus_algo_control (struct smbus_adapter *adap, unsigned int cmd, 
+                         unsigned long arg)
+{
+  return 0;
+}
+
+/* Ehm... This is called when a client is registered to an adapter. We could
+   do all kinds of neat stuff here like, ehm - returning success? */
+int smbus_client_register (struct smbus_client *client)
+{
+  return 0;
+}
+  
+int smbus_client_unregister (struct smbus_client *client)
+{
+  return 0;
+}
+
+/* Next: define SMBus variants of registering. Very boring. To make it possible
+   to change these definitions in the future without recompiling all modules,
+   we do not define them as inline. */
+int smbus_add_algorithm(struct smbus_algorithm *algorithm)
+{
+  return i2c_add_algorithm( (struct i2c_algorithm *) algorithm);
+}
+
+int smbus_del_algorithm(struct smbus_algorithm *algorithm)
+{
+  return i2c_del_algorithm( (struct i2c_algorithm *) algorithm);
+}
+
+int smbus_add_adapter(struct smbus_adapter *adapter)
+{
+  return i2c_add_adapter( (struct i2c_adapter *) adapter);
+}
+
+int smbus_del_adapter(struct smbus_adapter *adapter)
+{
+  return i2c_del_adapter( (struct i2c_adapter *) adapter);
+}
+
+int smbus_add_driver(struct smbus_driver *driver)
+{
+  return i2c_add_driver( (struct i2c_driver *) driver);
+}
+
+int smbus_del_driver(struct smbus_driver *driver)
+{
+  return i2c_del_driver( (struct i2c_driver *) driver);
+}
+
+int smbus_attach_client(struct smbus_client *client)
+{
+  return i2c_attach_client( (struct i2c_client *) client);
+}
+
+int smbus_detach_client(struct smbus_client *client)
+{
+  return i2c_detach_client( (struct i2c_client *) client);
+}
+
+int smbus_init(void)
+{
+  int res;
+  if ((res = smbus_add_algorithm(&smbus_algorithm)))
+    printk("Module smbus.o not inserted!\n");
+  else
+    printk("smbus.o initialized");
+  return res;
+}
+
+int smbus_cleanup(void)
+{
+  int res;
+  if ((res = smbus_del_algorithm(&smbus_algorithm)))
+    printk("Module smbus.o could not be removed cleanly!\n");
+  return res;
+}
+
+/* OK, this will for now _only_ compile as a module, but this is neat for
+   later, if we want to compile it straight into the kernel */
+#ifdef MODULE
+
+MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
+MODULE_DESCRIPTION("System Management Bus (SMBus) access");
+
+int init_module(void)
+{
+  return smbus_init();
+}
+
+int cleanup_module(void)
+{
+  return smbus_cleanup();
+}
+
+#endif /* MODULE */
diff --git a/src/smbus.h b/src/smbus.h
new file mode 100644
index 00000000..bbe2334b
--- /dev/null
+++ b/src/smbus.h
@@ -0,0 +1,270 @@
+/*
+    smbus.h - A Linux module for reading sensor data.
+    Copyright (c) 1998  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.
+*/
+
+#ifndef SENSORS_SMBUS_H
+#define SENSORS_SMBUS_H
+
+/* This file must interface with Simon Vogl's i2c driver. Version 19981006 is
+   OK, earlier versions are not; later versions will probably give problems
+   too. 
+*/
+#ifdef I2C
+#include "i2c/i2c.h"
+#else /* def I2C */
+#include <linux/i2c.h>
+#endif /* def I2C */
+
+#include <asm/types.h>
+
+/* SPINLOCK is defined in i2c.h. */
+#ifdef SPINLOCK
+#include <asm/spinlock.h>
+#else
+#include <asm/semaphore.h>
+#endif
+
+/* Declarations, to keep the compiler happy */
+struct smbus_driver;
+struct smbus_client;
+struct smbus_algorithm;
+struct smbus_adapter;
+union smbus_data;
+
+/* A driver tells us how we should handle a specific kind of chip.
+   A specific instance of such a chip is called a client.  
+   This structure is essentially the same as i2c_driver. */
+struct smbus_driver {
+  char name[32];
+  int id;
+  unsigned int flags;
+  int (* attach_adapter) (struct smbus_adapter *);
+  int (* detach_client) (struct smbus_client *);
+  int (* command) (struct smbus_client *, unsigned int cmd, void *arg);
+  void (* inc_use) (struct smbus_client *);
+  void (* dec_use) (struct smbus_client *);
+};
+
+/* A client is a specifc instance of a chip: for each detected chip, there will
+   be a client. Its operation is controlled by a driver.
+   This structure is essentially the same as i2c_client. */
+struct smbus_client {
+  char name[32];
+  int id;
+  unsigned int flags;
+  unsigned char addr;
+  struct smbus_adapter *adapter;
+  struct smbus_driver *driver;
+  void *data;
+};
+
+/* An algorithm describes how a certain class of busses can be accessed. 
+   A specific instance of sucj a bus is called an adapter. 
+   This structure is essentially the same as i2c_adapter. */
+struct smbus_algorithm {
+  char name[32];
+  unsigned int id;
+  int (* master_xfer) (struct smbus_adapter *adap, struct i2c_msg msgs[],
+                       int num);
+  int (* slave_send) (struct smbus_adapter *,char *, int);
+  int (* slave_recv) (struct smbus_adapter *,char *, int);
+  int (* algo_control) (struct smbus_adapter *, unsigned int, unsigned long);
+  int (* client_register) (struct smbus_client *);
+  int (* client_unregister) (struct smbus_client *);
+};
+
+/* An adapter is a specifc instance of a bus: for each detected bus, there will
+   be an adapter. Its operation is controlled by an algorithm. 
+   SPINLOCK must be the same as declared in i2c.h.
+   This structure is an extension of i2c_algorithm. */
+struct smbus_adapter {
+  char name[32];
+  unsigned int id;
+  struct smbus_algorithm *algo;
+  void *data;
+#ifdef SPINLOCK
+  spinlock_t lock;
+  unsigned long lockflags;
+#else
+  struct semaphore lock;
+#endif
+  unsigned int flags;
+  struct smbus_client *clients[I2C_CLIENT_MAX];
+  int client_count;
+  int timeout;
+  int retries;
+
+  /* Here ended i2c_algorithm */
+  s32 (* smbus_access) (__u8 addr, char read_write,
+                        __u8 command, int size, union smbus_data * data);
+};
+
+/* We need to mark SMBus algorithms in the algorithm structure. 
+   Note that any and all adapters using a non-i2c driver use in this
+   setup ALGO_SMBUS. Adapters define their own smbus access routine. 
+   This also means that adapter->smbus_access is only available if
+   this flag is set! */
+#define ALGO_SMBUS 0x40000
+
+/* This union is used within smbus_access routines */
+union smbus_data { 
+        __u8 byte;
+        __u16 word;
+        __u8 block[32];
+};
+
+/* smbus_access read or write markers */
+#define SMBUS_READ      1
+#define SMBUS_WRITE     0
+
+/* SMBus transaction types (size parameter in the above functions) 
+   Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
+#define SMBUS_QUICK      0
+#define SMBUS_BYTE       1
+#define SMBUS_BYTE_DATA  2 
+#define SMBUS_WORD_DATA  3
+#define SMBUS_PROC_CALL  4
+#define SMBUS_BLOCK_DATA 5
+
+/* Declare an algorithm structure. All SMBus derived adapters should use this
+   algorithm! */
+extern struct smbus_algorithm smbus_algorithm;
+
+/* This is the very generalized SMBus access routine. You probably do not
+   want to use this, though; one of the functions below may be much easier,
+   and probably just as fast. */
+extern s32 smbus_access (struct smbus_adapter * adapter, u8 addr, 
+                         char read_write, u8 command, int size,
+                         union smbus_data * data);
+
+/* Now follow the 'nice' access routines. These also document the calling
+   conventions of smbus_access. */
+
+extern inline s32 smbus_write_quick(struct smbus_adapter * adapter, u8 addr, 
+                                    u8 value)
+{
+  return smbus_access(adapter,addr,value,0,SMBUS_QUICK,NULL);
+}
+
+extern inline s32 smbus_read_byte(struct smbus_adapter * adapter,u8 addr)
+{
+  union smbus_data data;
+  if (smbus_access(adapter,addr,SMBUS_READ,0,SMBUS_BYTE,&data))
+    return -1;
+  else
+    return data.byte;
+}
+
+extern inline s32 smbus_write_byte(struct smbus_adapter * adapter, u8 addr, 
+                                   u8 value)
+{
+  return smbus_access(adapter,addr,SMBUS_WRITE,value, SMBUS_BYTE,NULL);
+}
+
+extern inline s32 smbus_read_byte_data(struct smbus_adapter * adapter,
+                                       u8 addr, u8 command)
+{
+  union smbus_data data;
+  if (smbus_access(adapter,addr,SMBUS_READ,command,SMBUS_BYTE_DATA,&data))
+    return -1;
+  else
+    return data.byte;
+}
+
+extern inline s32 smbus_write_byte_data(struct smbus_adapter * adapter,
+                                        u8 addr, u8 command, u8 value)
+{
+  union smbus_data data;
+  data.byte = value;
+  return smbus_access(adapter,addr,SMBUS_WRITE,command,SMBUS_BYTE_DATA,&data);
+}
+
+extern inline s32 smbus_read_word_data(struct smbus_adapter * adapter,
+                                       u8 addr, u8 command)
+{
+  union smbus_data data;
+  if (smbus_access(adapter,addr,SMBUS_READ,command,SMBUS_WORD_DATA,&data))
+    return -1;
+  else
+    return data.word;
+}
+
+extern inline s32 smbus_write_word_data(struct smbus_adapter * adapter,
+                                        u8 addr, u8 command, u16 value)
+{
+  union smbus_data data;
+  data.word = value;
+  return smbus_access(adapter,addr,SMBUS_WRITE,command,SMBUS_WORD_DATA,&data);
+}
+
+extern inline s32 smbus_process_call(struct smbus_adapter * adapter,
+                                     u8 addr, u8 command, u16 value)
+{
+  union smbus_data data;
+  data.word = value;
+  if (smbus_access(adapter,addr,SMBUS_WRITE,command,SMBUS_PROC_CALL,&data))
+    return -1;
+  else
+    return data.word;
+}
+
+/* Returns the number of read bytes */
+extern inline s32 smbus_read_block_data(struct smbus_adapter * adapter,
+                                        u8 addr, u8 command, u8 *values)
+{
+  union smbus_data data;
+  int i;
+  if (smbus_access(adapter,addr,SMBUS_READ,command,SMBUS_BLOCK_DATA,&data))
+    return -1;
+  else {
+    for (i = 1; i <= data.block[0]; i++)
+      values[i-1] = data.block[i];
+    return data.block[0];
+  }
+}
+
+extern inline int smbus_write_block_data(struct smbus_adapter * adapter,
+                                         u8 addr, u8 command, u8 length,
+                                         u8 *values)
+{
+  union smbus_data data;
+  int i;
+  if (length > 32)
+    length = 32;
+  for (i = 1; i <= length; i++)
+    data.block[i] = values[i-1];
+  data.block[0] = length;
+  return smbus_access(adapter,addr,SMBUS_WRITE,command,SMBUS_BLOCK_DATA,&data);
+}
+
+/* Next: define SMBus variants of registering. */
+extern int smbus_add_algorithm(struct smbus_algorithm *algorithm);
+extern int smbus_del_algorithm(struct smbus_algorithm *algorithm);
+
+extern int smbus_add_adapter(struct smbus_adapter *adapter);
+extern int smbus_del_adapter(struct smbus_adapter *adapter);
+
+extern int smbus_add_driver(struct smbus_driver *driver);
+extern int smbus_del_driver(struct smbus_driver *driver);
+
+extern int smbus_attach_client(struct smbus_client *client);
+extern int smbus_detach_client(struct smbus_client *client);
+
+
+#endif /* ndef SENSORS_SMBUS_H */
+