ChangeSet 1.977.29.2, 2003/03/25 17:29:08-08:00, j.dittmer@portrix.net

[PATCH] i2c: add i2c-via686a driver


 drivers/i2c/chips/Kconfig   |   13 
 drivers/i2c/chips/Makefile  |    1 
 drivers/i2c/chips/via686a.c |  952 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 966 insertions(+)


diff -Nru a/drivers/i2c/chips/Kconfig b/drivers/i2c/chips/Kconfig
--- a/drivers/i2c/chips/Kconfig	Wed Apr  2 16:02:02 2003
+++ b/drivers/i2c/chips/Kconfig	Wed Apr  2 16:02:02 2003
@@ -37,4 +37,17 @@
 	  in the lm_sensors package, which you can download at 
 	  http://www.lm-sensors.nu
 
+config SENSORS_VIA686A
+	tristate "  VIA686A"
+	depends on I2C && I2C_PROC
+	help
+	  support for via686a
+	  If you say yes here you get support for the integrated sensors in
+	  Via 686A/B South Bridges. This can also be built as a module
+	  which can be inserted and removed while the kernel is running.
+
+	  You will also need the latest user-space utilties: you can find them
+	  in the lm_sensors package, which you can download at
+	  http://www.lm-sensors.nu
+
 endmenu
diff -Nru a/drivers/i2c/chips/Makefile b/drivers/i2c/chips/Makefile
--- a/drivers/i2c/chips/Makefile	Wed Apr  2 16:02:02 2003
+++ b/drivers/i2c/chips/Makefile	Wed Apr  2 16:02:02 2003
@@ -4,3 +4,4 @@
 
 obj-$(CONFIG_SENSORS_ADM1021)	+= adm1021.o
 obj-$(CONFIG_SENSORS_LM75)	+= lm75.o
+obj-$(CONFIG_SENSORS_VIA686A)	+= via686a.o
diff -Nru a/drivers/i2c/chips/via686a.c b/drivers/i2c/chips/via686a.c
--- /dev/null	Wed Dec 31 16:00:00 1969
+++ b/drivers/i2c/chips/via686a.c	Wed Apr  2 16:02:02 2003
@@ -0,0 +1,952 @@
+/*
+    via686a.c - Part of lm_sensors, Linux kernel modules
+                for hardware monitoring
+                
+    Copyright (c) 1998 - 2002  Frodo Looijaard <frodol@dds.nl>,
+                        Ky�sti M�lkki <kmalkki@cc.hut.fi>,
+			Mark Studebaker <mdsxyz123@yahoo.com>,
+			and Bob Dougherty <bobd@stanford.edu>
+    (Some conversion-factor data were contributed by Jonathan Teh Soon Yew 
+    <j.teh@iname.com> and Alex van Kaam <darkside@chello.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 the Via VT82C686A, VT82C686B south bridges.
+    Reports all as a 686A.
+    See doc/chips/via686a for details.
+    Warning - only supports a single device.
+*/
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/i2c-proc.h>
+#include <linux/init.h>
+#include <asm/io.h>
+
+
+/* If force_addr is set to anything different from 0, we forcibly enable
+   the device at the given address. */
+static int force_addr = 0;
+MODULE_PARM(force_addr, "i");
+MODULE_PARM_DESC(force_addr,
+		 "Initialize the base address of the sensors");
+
+/* Addresses to scan.
+   Note that we can't determine the ISA address until we have initialized
+   our module */
+static unsigned short normal_i2c[] = { SENSORS_I2C_END };
+static unsigned short normal_i2c_range[] = { SENSORS_I2C_END };
+static unsigned int normal_isa[] = { 0x0000, SENSORS_ISA_END };
+static unsigned int normal_isa_range[] = { SENSORS_ISA_END };
+
+/* Insmod parameters */
+SENSORS_INSMOD_1(via686a);
+
+/*
+   The Via 686a southbridge has a LM78-like chip integrated on the same IC.
+   This driver is a customized copy of lm78.c
+*/
+
+/* Many VIA686A constants specified below */
+
+/* Length of ISA address segment */
+#define VIA686A_EXTENT 0x80
+#define VIA686A_BASE_REG 0x70
+#define VIA686A_ENABLE_REG 0x74
+
+/* The VIA686A registers */
+/* ins numbered 0-4 */
+#define VIA686A_REG_IN_MAX(nr) (0x2b + ((nr) * 2))
+#define VIA686A_REG_IN_MIN(nr) (0x2c + ((nr) * 2))
+#define VIA686A_REG_IN(nr)     (0x22 + (nr))
+
+/* fans numbered 1-2 */
+#define VIA686A_REG_FAN_MIN(nr) (0x3a + (nr))
+#define VIA686A_REG_FAN(nr)     (0x28 + (nr))
+
+/* the following values are as speced by VIA: */
+static const u8 regtemp[] = { 0x20, 0x21, 0x1f };
+static const u8 regover[] = { 0x39, 0x3d, 0x1d };
+static const u8 reghyst[] = { 0x3a, 0x3e, 0x1e };
+
+/* temps numbered 1-3 */
+#define VIA686A_REG_TEMP(nr)		(regtemp[(nr) - 1])
+#define VIA686A_REG_TEMP_OVER(nr)	(regover[(nr) - 1])
+#define VIA686A_REG_TEMP_HYST(nr)	(reghyst[(nr) - 1])
+#define VIA686A_REG_TEMP_LOW1	0x4b	// bits 7-6
+#define VIA686A_REG_TEMP_LOW23	0x49	// 2 = bits 5-4, 3 = bits 7-6
+
+#define VIA686A_REG_ALARM1 0x41
+#define VIA686A_REG_ALARM2 0x42
+#define VIA686A_REG_FANDIV 0x47
+#define VIA686A_REG_CONFIG 0x40
+/* The following register sets temp interrupt mode (bits 1-0 for temp1, 
+ 3-2 for temp2, 5-4 for temp3).  Modes are:
+    00 interrupt stays as long as value is out-of-range
+    01 interrupt is cleared once register is read (default)
+    10 comparator mode- like 00, but ignores hysteresis
+    11 same as 00 */
+#define VIA686A_REG_TEMP_MODE 0x4b
+/* We'll just assume that you want to set all 3 simultaneously: */
+#define VIA686A_TEMP_MODE_MASK 0x3F
+#define VIA686A_TEMP_MODE_CONTINUOUS (0x00)
+
+/* Conversions. Rounding and limit checking is only done on the TO_REG
+   variants. 
+
+********* VOLTAGE CONVERSIONS (Bob Dougherty) ********
+ From HWMon.cpp (Copyright 1998-2000 Jonathan Teh Soon Yew):
+ voltagefactor[0]=1.25/2628; (2628/1.25=2102.4)   // Vccp
+ voltagefactor[1]=1.25/2628; (2628/1.25=2102.4)   // +2.5V
+ voltagefactor[2]=1.67/2628; (2628/1.67=1573.7)   // +3.3V
+ voltagefactor[3]=2.6/2628;  (2628/2.60=1010.8)   // +5V
+ voltagefactor[4]=6.3/2628;  (2628/6.30=417.14)   // +12V
+ in[i]=(data[i+2]*25.0+133)*voltagefactor[i];
+ That is:
+ volts = (25*regVal+133)*factor
+ regVal = (volts/factor-133)/25
+ (These conversions were contributed by Jonathan Teh Soon Yew 
+ <j.teh@iname.com>)
+ 
+ These get us close, but they don't completely agree with what my BIOS 
+ says- they are all a bit low.  But, it all we have to go on... */
+static inline u8 IN_TO_REG(long val, int inNum)
+{
+	/* to avoid floating point, we multiply everything by 100.
+	 val is guaranteed to be positive, so we can achieve the effect of 
+	 rounding by (...*10+5)/10.  Note that the *10 is hidden in the 
+	 /250 (which should really be /2500).
+	 At the end, we need to /100 because we *100 everything and we need
+	 to /10 because of the rounding thing, so we /1000.   */
+	if (inNum <= 1)
+		return (u8)
+		    SENSORS_LIMIT(((val * 210240 - 13300) / 250 + 5) / 1000, 
+				  0, 255);
+	else if (inNum == 2)
+		return (u8)
+		    SENSORS_LIMIT(((val * 157370 - 13300) / 250 + 5) / 1000, 
+				  0, 255);
+	else if (inNum == 3)
+		return (u8)
+		    SENSORS_LIMIT(((val * 101080 - 13300) / 250 + 5) / 1000, 
+				  0, 255);
+	else
+		return (u8) SENSORS_LIMIT(((val * 41714 - 13300) / 250 + 5)
+					  / 1000, 0, 255);
+}
+
+static inline long IN_FROM_REG(u8 val, int inNum)
+{
+	/* to avoid floating point, we multiply everything by 100.
+	 val is guaranteed to be positive, so we can achieve the effect of
+	 rounding by adding 0.5.  Or, to avoid fp math, we do (...*10+5)/10.
+	 We need to scale with *100 anyway, so no need to /100 at the end. */
+	if (inNum <= 1)
+		return (long) (((250000 * val + 13300) / 210240 * 10 + 5) /10);
+	else if (inNum == 2)
+		return (long) (((250000 * val + 13300) / 157370 * 10 + 5) /10);
+	else if (inNum == 3)
+		return (long) (((250000 * val + 13300) / 101080 * 10 + 5) /10);
+	else
+		return (long) (((250000 * val + 13300) / 41714 * 10 + 5) /10);
+}
+
+/********* FAN RPM CONVERSIONS ********/
+/* Higher register values = slower fans (the fan's strobe gates a counter).
+ But this chip saturates back at 0, not at 255 like all the other chips.
+ So, 0 means 0 RPM */
+static inline u8 FAN_TO_REG(long rpm, int div)
+{
+	if (rpm == 0)
+		return 0;
+	rpm = SENSORS_LIMIT(rpm, 1, 1000000);
+	return SENSORS_LIMIT((1350000 + rpm * div / 2) / (rpm * div), 1, 255);
+}
+
+#define FAN_FROM_REG(val,div) ((val)==0?0:(val)==255?0:1350000/((val)*(div)))
+
+/******** TEMP CONVERSIONS (Bob Dougherty) *********/
+/* linear fits from HWMon.cpp (Copyright 1998-2000 Jonathan Teh Soon Yew)
+      if(temp<169)
+              return double(temp)*0.427-32.08;
+      else if(temp>=169 && temp<=202)
+              return double(temp)*0.582-58.16;
+      else
+              return double(temp)*0.924-127.33;
+
+ A fifth-order polynomial fits the unofficial data (provided by Alex van 
+ Kaam <darkside@chello.nl>) a bit better.  It also give more reasonable 
+ numbers on my machine (ie. they agree with what my BIOS tells me).  
+ Here's the fifth-order fit to the 8-bit data:
+ temp = 1.625093e-10*val^5 - 1.001632e-07*val^4 + 2.457653e-05*val^3 - 
+        2.967619e-03*val^2 + 2.175144e-01*val - 7.090067e+0.
+
+ (2000-10-25- RFD: thanks to Uwe Andersen <uandersen@mayah.com> for 
+ finding my typos in this formula!)
+
+ Alas, none of the elegant function-fit solutions will work because we 
+ aren't allowed to use floating point in the kernel and doing it with 
+ integers doesn't rpovide enough precision.  So we'll do boring old 
+ look-up table stuff.  The unofficial data (see below) have effectively 
+ 7-bit resolution (they are rounded to the nearest degree).  I'm assuming 
+ that the transfer function of the device is monotonic and smooth, so a 
+ smooth function fit to the data will allow us to get better precision.  
+ I used the 5th-order poly fit described above and solved for
+ VIA register values 0-255.  I *10 before rounding, so we get tenth-degree 
+ precision.  (I could have done all 1024 values for our 10-bit readings, 
+ but the function is very linear in the useful range (0-80 deg C), so 
+ we'll just use linear interpolation for 10-bit readings.)  So, tempLUT 
+ is the temp at via register values 0-255: */
+static const long tempLUT[] =
+    { -709, -688, -667, -646, -627, -607, -589, -570, -553, -536, -519,
+	    -503, -487, -471, -456, -442, -428, -414, -400, -387, -375,
+	    -362, -350, -339, -327, -316, -305, -295, -285, -275, -265,
+	    -255, -246, -237, -229, -220, -212, -204, -196, -188, -180,
+	    -173, -166, -159, -152, -145, -139, -132, -126, -120, -114,
+	    -108, -102, -96, -91, -85, -80, -74, -69, -64, -59, -54, -49,
+	    -44, -39, -34, -29, -25, -20, -15, -11, -6, -2, 3, 7, 12, 16,
+	    20, 25, 29, 33, 37, 42, 46, 50, 54, 59, 63, 67, 71, 75, 79, 84,
+	    88, 92, 96, 100, 104, 109, 113, 117, 121, 125, 130, 134, 138,
+	    142, 146, 151, 155, 159, 163, 168, 172, 176, 181, 185, 189,
+	    193, 198, 202, 206, 211, 215, 219, 224, 228, 232, 237, 241,
+	    245, 250, 254, 259, 263, 267, 272, 276, 281, 285, 290, 294,
+	    299, 303, 307, 312, 316, 321, 325, 330, 334, 339, 344, 348,
+	    353, 357, 362, 366, 371, 376, 380, 385, 390, 395, 399, 404,
+	    409, 414, 419, 423, 428, 433, 438, 443, 449, 454, 459, 464,
+	    469, 475, 480, 486, 491, 497, 502, 508, 514, 520, 526, 532,
+	    538, 544, 551, 557, 564, 571, 578, 584, 592, 599, 606, 614,
+	    621, 629, 637, 645, 654, 662, 671, 680, 689, 698, 708, 718,
+	    728, 738, 749, 759, 770, 782, 793, 805, 818, 830, 843, 856,
+	    870, 883, 898, 912, 927, 943, 958, 975, 991, 1008, 1026, 1044,
+	    1062, 1081, 1101, 1121, 1141, 1162, 1184, 1206, 1229, 1252,
+	    1276, 1301, 1326, 1352, 1378, 1406, 1434, 1462
+};
+
+/* the original LUT values from Alex van Kaam <darkside@chello.nl> 
+   (for via register values 12-240):
+{-50,-49,-47,-45,-43,-41,-39,-38,-37,-35,-34,-33,-32,-31,
+-30,-29,-28,-27,-26,-25,-24,-24,-23,-22,-21,-20,-20,-19,-18,-17,-17,-16,-15,
+-15,-14,-14,-13,-12,-12,-11,-11,-10,-9,-9,-8,-8,-7,-7,-6,-6,-5,-5,-4,-4,-3,
+-3,-2,-2,-1,-1,0,0,1,1,1,3,3,3,4,4,4,5,5,5,6,6,7,7,8,8,9,9,9,10,10,11,11,12,
+12,12,13,13,13,14,14,15,15,16,16,16,17,17,18,18,19,19,20,20,21,21,21,22,22,
+22,23,23,24,24,25,25,26,26,26,27,27,27,28,28,29,29,30,30,30,31,31,32,32,33,
+33,34,34,35,35,35,36,36,37,37,38,38,39,39,40,40,41,41,42,42,43,43,44,44,45,
+45,46,46,47,48,48,49,49,50,51,51,52,52,53,53,54,55,55,56,57,57,58,59,59,60,
+61,62,62,63,64,65,66,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,83,84,
+85,86,88,89,91,92,94,96,97,99,101,103,105,107,109,110};
+
+
+ Here's the reverse LUT.  I got it by doing a 6-th order poly fit (needed
+ an extra term for a good fit to these inverse data!) and then 
+ solving for each temp value from -50 to 110 (the useable range for 
+ this chip).  Here's the fit: 
+ viaRegVal = -1.160370e-10*val^6 +3.193693e-08*val^5 - 1.464447e-06*val^4 
+ - 2.525453e-04*val^3 + 1.424593e-02*val^2 + 2.148941e+00*val +7.275808e+01)
+ Note that n=161: */
+static const u8 viaLUT[] =
+    { 12, 12, 13, 14, 14, 15, 16, 16, 17, 18, 18, 19, 20, 20, 21, 22, 23,
+	    23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 35, 36, 37, 39, 40,
+	    41, 43, 45, 46, 48, 49, 51, 53, 55, 57, 59, 60, 62, 64, 66,
+	    69, 71, 73, 75, 77, 79, 82, 84, 86, 88, 91, 93, 95, 98, 100,
+	    103, 105, 107, 110, 112, 115, 117, 119, 122, 124, 126, 129,
+	    131, 134, 136, 138, 140, 143, 145, 147, 150, 152, 154, 156,
+	    158, 160, 162, 164, 166, 168, 170, 172, 174, 176, 178, 180,
+	    182, 183, 185, 187, 188, 190, 192, 193, 195, 196, 198, 199,
+	    200, 202, 203, 205, 206, 207, 208, 209, 210, 211, 212, 213,
+	    214, 215, 216, 217, 218, 219, 220, 221, 222, 222, 223, 224,
+	    225, 226, 226, 227, 228, 228, 229, 230, 230, 231, 232, 232,
+	    233, 233, 234, 235, 235, 236, 236, 237, 237, 238, 238, 239,
+	    239, 240
+};
+
+/* Converting temps to (8-bit) hyst and over registers 
+ No interpolation here.  Just check the limits and go.
+ The +5 effectively rounds off properly and the +50 is because 
+ the temps start at -50 */
+static inline u8 TEMP_TO_REG(long val)
+{
+	return (u8)
+	    SENSORS_LIMIT(viaLUT[((val <= -500) ? 0 : (val >= 1100) ? 160 : 
+				  ((val + 5) / 10 + 50))], 0, 255);
+}
+
+/* for 8-bit temperature hyst and over registers 
+ The temp values are already *10, so we don't need to do that.
+ But we _will_ round these off to the nearest degree with (...*10+5)/10 */
+#define TEMP_FROM_REG(val) ((tempLUT[(val)]*10+5)/10)
+
+/* for 10-bit temperature readings 
+ You might _think_ this is too long to inline, but's it's really only
+ called once... */
+static inline long TEMP_FROM_REG10(u16 val)
+{
+	/* the temp values are already *10, so we don't need to do that. */
+	long temp;
+	u16 eightBits = val >> 2;
+	u16 twoBits = val & 3;
+
+	/* handle the extremes first (they won't interpolate well! ;-) */
+	if (val == 0)
+		return (long) tempLUT[0];
+	if (val == 1023)
+		return (long) tempLUT[255];
+
+	if (twoBits == 0)
+		return (long) tempLUT[eightBits];
+	else {
+		/* do some interpolation by multipying the lower and upper
+		 bounds by 25, 50 or 75, then /100. */
+		temp = ((25 * (4 - twoBits)) * tempLUT[eightBits]
+			+ (25 * twoBits) * tempLUT[eightBits + 1]);
+		/* increase the magnitude by 50 to achieve rounding. */
+		if (temp > 0)
+			temp += 50;
+		else
+			temp -= 50;
+		return (temp / 100);
+	}
+}
+
+#define ALARMS_FROM_REG(val) (val)
+
+#define DIV_FROM_REG(val) (1 << (val))
+#define DIV_TO_REG(val) ((val)==8?3:(val)==4?2:(val)==1?0:1)
+
+/* Initial limits */
+#define VIA686A_INIT_IN_0 200
+#define VIA686A_INIT_IN_1 250
+#define VIA686A_INIT_IN_2 330
+#define VIA686A_INIT_IN_3 500
+#define VIA686A_INIT_IN_4 1200
+
+#define VIA686A_INIT_IN_PERCENTAGE 10
+
+#define VIA686A_INIT_IN_MIN_0 (VIA686A_INIT_IN_0 - VIA686A_INIT_IN_0 \
+        * VIA686A_INIT_IN_PERCENTAGE / 100)
+#define VIA686A_INIT_IN_MAX_0 (VIA686A_INIT_IN_0 + VIA686A_INIT_IN_0 \
+        * VIA686A_INIT_IN_PERCENTAGE / 100)
+#define VIA686A_INIT_IN_MIN_1 (VIA686A_INIT_IN_1 - VIA686A_INIT_IN_1 \
+        * VIA686A_INIT_IN_PERCENTAGE / 100)
+#define VIA686A_INIT_IN_MAX_1 (VIA686A_INIT_IN_1 + VIA686A_INIT_IN_1 \
+        * VIA686A_INIT_IN_PERCENTAGE / 100)
+#define VIA686A_INIT_IN_MIN_2 (VIA686A_INIT_IN_2 - VIA686A_INIT_IN_2 \
+        * VIA686A_INIT_IN_PERCENTAGE / 100)
+#define VIA686A_INIT_IN_MAX_2 (VIA686A_INIT_IN_2 + VIA686A_INIT_IN_2 \
+        * VIA686A_INIT_IN_PERCENTAGE / 100)
+#define VIA686A_INIT_IN_MIN_3 (VIA686A_INIT_IN_3 - VIA686A_INIT_IN_3 \
+        * VIA686A_INIT_IN_PERCENTAGE / 100)
+#define VIA686A_INIT_IN_MAX_3 (VIA686A_INIT_IN_3 + VIA686A_INIT_IN_3 \
+        * VIA686A_INIT_IN_PERCENTAGE / 100)
+#define VIA686A_INIT_IN_MIN_4 (VIA686A_INIT_IN_4 - VIA686A_INIT_IN_4 \
+        * VIA686A_INIT_IN_PERCENTAGE / 100)
+#define VIA686A_INIT_IN_MAX_4 (VIA686A_INIT_IN_4 + VIA686A_INIT_IN_4 \
+        * VIA686A_INIT_IN_PERCENTAGE / 100)
+
+#define VIA686A_INIT_FAN_MIN	3000
+
+#define VIA686A_INIT_TEMP_OVER 600
+#define VIA686A_INIT_TEMP_HYST 500
+
+/* For the VIA686A, we need to keep some data in memory. That
+   data is pointed to by via686a_list[NR]->data. The structure itself is
+   dynamically allocated, at the same time when a new via686a client is
+   allocated. */
+struct via686a_data {
+	int sysctl_id;
+
+	struct semaphore update_lock;
+	char valid;		/* !=0 if following fields are valid */
+	unsigned long last_updated;	/* In jiffies */
+
+	u8 in[5];		/* Register value */
+	u8 in_max[5];		/* Register value */
+	u8 in_min[5];		/* Register value */
+	u8 fan[2];		/* Register value */
+	u8 fan_min[2];		/* Register value */
+	u16 temp[3];		/* Register value 10 bit */
+	u8 temp_over[3];	/* Register value */
+	u8 temp_hyst[3];	/* Register value */
+	u8 fan_div[2];		/* Register encoding, shifted right */
+	u16 alarms;		/* Register encoding, combined */
+};
+
+static struct pci_dev *s_bridge;	/* pointer to the (only) via686a */
+
+static int via686a_attach_adapter(struct i2c_adapter *adapter);
+static int via686a_detect(struct i2c_adapter *adapter, int address,
+			  unsigned short flags, int kind);
+static int via686a_detach_client(struct i2c_client *client);
+
+static int via686a_read_value(struct i2c_client *client, u8 register);
+static void via686a_write_value(struct i2c_client *client, u8 register,
+				u8 value);
+static void via686a_update_client(struct i2c_client *client);
+static void via686a_init_client(struct i2c_client *client);
+
+
+static void via686a_in(struct i2c_client *client, int operation,
+		       int ctl_name, int *nrels_mag, long *results);
+static void via686a_fan(struct i2c_client *client, int operation,
+			int ctl_name, int *nrels_mag, long *results);
+static void via686a_temp(struct i2c_client *client, int operation,
+			 int ctl_name, int *nrels_mag, long *results);
+static void via686a_alarms(struct i2c_client *client, int operation,
+			   int ctl_name, int *nrels_mag, long *results);
+static void via686a_fan_div(struct i2c_client *client, int operation,
+			    int ctl_name, int *nrels_mag, long *results);
+
+static int via686a_id = 0;
+
+/* The driver. I choose to use type i2c_driver, as at is identical to both
+   smbus_driver and isa_driver, and clients could be of either kind */
+static struct i2c_driver via686a_driver = {
+	.owner		= THIS_MODULE,
+	.name		= "VIA686A",
+	.id		= I2C_DRIVERID_VIA686A,
+	.flags		= I2C_DF_NOTIFY,
+	.attach_adapter	= via686a_attach_adapter,
+	.detach_client	= via686a_detach_client,
+};
+
+
+
+/* The /proc/sys entries */
+
+/* -- SENSORS SYSCTL START -- */
+#define VIA686A_SYSCTL_IN0 1000
+#define VIA686A_SYSCTL_IN1 1001
+#define VIA686A_SYSCTL_IN2 1002
+#define VIA686A_SYSCTL_IN3 1003
+#define VIA686A_SYSCTL_IN4 1004
+#define VIA686A_SYSCTL_FAN1 1101
+#define VIA686A_SYSCTL_FAN2 1102
+#define VIA686A_SYSCTL_TEMP 1200
+#define VIA686A_SYSCTL_TEMP2 1201
+#define VIA686A_SYSCTL_TEMP3 1202
+#define VIA686A_SYSCTL_FAN_DIV 2000
+#define VIA686A_SYSCTL_ALARMS 2001
+
+#define VIA686A_ALARM_IN0 0x01
+#define VIA686A_ALARM_IN1 0x02
+#define VIA686A_ALARM_IN2 0x04
+#define VIA686A_ALARM_IN3 0x08
+#define VIA686A_ALARM_TEMP 0x10
+#define VIA686A_ALARM_FAN1 0x40
+#define VIA686A_ALARM_FAN2 0x80
+#define VIA686A_ALARM_IN4 0x100
+#define VIA686A_ALARM_TEMP2 0x800
+#define VIA686A_ALARM_CHAS 0x1000
+#define VIA686A_ALARM_TEMP3 0x8000
+
+/* -- SENSORS SYSCTL END -- */
+
+/* These files are created for each detected VIA686A. 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 via686a_dir_table_template[] = {
+	{VIA686A_SYSCTL_IN0, "in0", NULL, 0, 0644, NULL, &i2c_proc_real,
+	 &i2c_sysctl_real, NULL, &via686a_in},
+	{VIA686A_SYSCTL_IN1, "in1", NULL, 0, 0644, NULL, &i2c_proc_real,
+	 &i2c_sysctl_real, NULL, &via686a_in},
+	{VIA686A_SYSCTL_IN2, "in2", NULL, 0, 0644, NULL, &i2c_proc_real,
+	 &i2c_sysctl_real, NULL, &via686a_in},
+	{VIA686A_SYSCTL_IN3, "in3", NULL, 0, 0644, NULL, &i2c_proc_real,
+	 &i2c_sysctl_real, NULL, &via686a_in},
+	{VIA686A_SYSCTL_IN4, "in4", NULL, 0, 0644, NULL, &i2c_proc_real,
+	 &i2c_sysctl_real, NULL, &via686a_in},
+	{VIA686A_SYSCTL_FAN1, "fan1", NULL, 0, 0644, NULL, &i2c_proc_real,
+	 &i2c_sysctl_real, NULL, &via686a_fan},
+	{VIA686A_SYSCTL_FAN2, "fan2", NULL, 0, 0644, NULL, &i2c_proc_real,
+	 &i2c_sysctl_real, NULL, &via686a_fan},
+	{VIA686A_SYSCTL_TEMP, "temp1", NULL, 0, 0644, NULL, &i2c_proc_real,
+	 &i2c_sysctl_real, NULL, &via686a_temp},
+	{VIA686A_SYSCTL_TEMP2, "temp2", NULL, 0, 0644, NULL,
+	 &i2c_proc_real, &i2c_sysctl_real, NULL, &via686a_temp},
+	{VIA686A_SYSCTL_TEMP3, "temp3", NULL, 0, 0644, NULL,
+	 &i2c_proc_real, &i2c_sysctl_real, NULL, &via686a_temp},
+	{VIA686A_SYSCTL_FAN_DIV, "fan_div", NULL, 0, 0644, NULL,
+	 &i2c_proc_real, &i2c_sysctl_real, NULL, &via686a_fan_div},
+	{VIA686A_SYSCTL_ALARMS, "alarms", NULL, 0, 0444, NULL,
+	 &i2c_proc_real, &i2c_sysctl_real, NULL, &via686a_alarms},
+	{0}
+};
+
+static inline int via686a_read_value(struct i2c_client *client, u8 reg)
+{
+	return (inb_p(client->addr + reg));
+}
+
+static inline void via686a_write_value(struct i2c_client *client, u8 reg,
+				       u8 value)
+{
+	outb_p(value, client->addr + reg);
+}
+
+/* This is called when the module is loaded */
+static int via686a_attach_adapter(struct i2c_adapter *adapter)
+{
+	return i2c_detect(adapter, &addr_data, via686a_detect);
+}
+
+int via686a_detect(struct i2c_adapter *adapter, int address,
+		   unsigned short flags, int kind)
+{
+	int i;
+	struct i2c_client *new_client;
+	struct via686a_data *data;
+	int err = 0;
+	const char *type_name = "via686a";
+	const char client_name[] = "via686a chip";
+	u16 val;
+
+	/* Make sure we are probing the ISA bus!!  */
+	if (!i2c_is_isa_adapter(adapter)) {
+		dev_err(&adapter->dev,
+		"via686a_detect called for an I2C bus adapter?!?\n");
+		return 0;
+	}
+
+	/* 8231 requires multiple of 256, we enforce that on 686 as well */
+	if(force_addr)
+		address = force_addr & 0xFF00;
+
+	if(force_addr) {
+		dev_warn(&adapter->dev,"forcing ISA address 0x%04X\n", address);
+		if (PCIBIOS_SUCCESSFUL !=
+		    pci_write_config_word(s_bridge, VIA686A_BASE_REG, address))
+			return -ENODEV;
+	}
+	if (PCIBIOS_SUCCESSFUL !=
+	    pci_read_config_word(s_bridge, VIA686A_ENABLE_REG, &val))
+		return -ENODEV;
+	if (!(val & 0x0001)) {
+		dev_warn(&adapter->dev,"enabling sensors\n");
+		if (PCIBIOS_SUCCESSFUL !=
+		    pci_write_config_word(s_bridge, VIA686A_ENABLE_REG,
+		                      val | 0x0001))
+			return -ENODEV;
+	}
+
+	/* Reserve the ISA region */
+	if (!request_region(address, VIA686A_EXTENT, "via686a-sensor")) {
+		dev_err(&adapter->dev,"region 0x%x already in use!\n",
+		       address);
+		return -ENODEV;
+	}
+
+	if (!(new_client = kmalloc(sizeof(struct i2c_client) +
+				   sizeof(struct via686a_data),
+				   GFP_KERNEL))) {
+		err = -ENOMEM;
+		goto ERROR0;
+	}
+
+	memset(new_client,0x00, sizeof(struct i2c_client) +
+				sizeof(struct via686a_data));
+	data = (struct via686a_data *) (new_client + 1);
+	i2c_set_clientdata(new_client, data);
+	new_client->addr = address;
+	new_client->adapter = adapter;
+	new_client->driver = &via686a_driver;
+	new_client->flags = 0;
+
+	/* Fill in the remaining client fields and put into the global list */
+	snprintf(new_client->dev.name, DEVICE_NAME_SIZE, client_name);
+
+	new_client->id = via686a_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 = i2c_register_entry((struct i2c_client *) new_client,
+					type_name,
+					via686a_dir_table_template)) < 0) {
+		err = i;
+		goto ERROR4;
+	}
+	data->sysctl_id = i;
+
+	/* Initialize the VIA686A chip */
+	via686a_init_client(new_client);
+	return 0;
+
+      ERROR4:
+	i2c_detach_client(new_client);
+      ERROR3:
+	release_region(address, VIA686A_EXTENT);
+	kfree(new_client);
+      ERROR0:
+	return err;
+}
+
+static int via686a_detach_client(struct i2c_client *client)
+{
+	int err;
+	struct via686a_data *data = i2c_get_clientdata(client);
+	i2c_deregister_entry(data->sysctl_id);
+
+	if ((err = i2c_detach_client(client))) {
+		dev_err(&client->dev,
+		"Client deregistration failed, client not detached.\n");
+		return err;
+	}
+
+	release_region(client->addr, VIA686A_EXTENT);
+	kfree(client);
+
+	return 0;
+}
+
+/* Called when we have found a new VIA686A. Set limits, etc. */
+static void via686a_init_client(struct i2c_client *client)
+{
+	int i;
+
+	/* Reset the device */
+	via686a_write_value(client, VIA686A_REG_CONFIG, 0x80);
+
+	/* Have to wait for reset to complete or else the following
+	   initializations won't work reliably. The delay was arrived at
+	   empirically, the datasheet doesn't tell you.
+	   Waiting for the reset bit to clear doesn't work, it
+	   clears in about 2-4 udelays and that isn't nearly enough. */
+	udelay(50);
+
+	via686a_write_value(client, VIA686A_REG_IN_MIN(0),
+			    IN_TO_REG(VIA686A_INIT_IN_MIN_0, 0));
+	via686a_write_value(client, VIA686A_REG_IN_MAX(0),
+			    IN_TO_REG(VIA686A_INIT_IN_MAX_0, 0));
+	via686a_write_value(client, VIA686A_REG_IN_MIN(1),
+			    IN_TO_REG(VIA686A_INIT_IN_MIN_1, 1));
+	via686a_write_value(client, VIA686A_REG_IN_MAX(1),
+			    IN_TO_REG(VIA686A_INIT_IN_MAX_1, 1));
+	via686a_write_value(client, VIA686A_REG_IN_MIN(2),
+			    IN_TO_REG(VIA686A_INIT_IN_MIN_2, 2));
+	via686a_write_value(client, VIA686A_REG_IN_MAX(2),
+			    IN_TO_REG(VIA686A_INIT_IN_MAX_2, 2));
+	via686a_write_value(client, VIA686A_REG_IN_MIN(3),
+			    IN_TO_REG(VIA686A_INIT_IN_MIN_3, 3));
+	via686a_write_value(client, VIA686A_REG_IN_MAX(3),
+			    IN_TO_REG(VIA686A_INIT_IN_MAX_3, 3));
+	via686a_write_value(client, VIA686A_REG_IN_MIN(4),
+			    IN_TO_REG(VIA686A_INIT_IN_MIN_4, 4));
+	via686a_write_value(client, VIA686A_REG_IN_MAX(4),
+			    IN_TO_REG(VIA686A_INIT_IN_MAX_4, 4));
+	via686a_write_value(client, VIA686A_REG_FAN_MIN(1),
+			    FAN_TO_REG(VIA686A_INIT_FAN_MIN, 2));
+	via686a_write_value(client, VIA686A_REG_FAN_MIN(2),
+			    FAN_TO_REG(VIA686A_INIT_FAN_MIN, 2));
+	for (i = 1; i <= 3; i++) {
+		via686a_write_value(client, VIA686A_REG_TEMP_OVER(i),
+				    TEMP_TO_REG(VIA686A_INIT_TEMP_OVER));
+		via686a_write_value(client, VIA686A_REG_TEMP_HYST(i),
+				    TEMP_TO_REG(VIA686A_INIT_TEMP_HYST));
+	}
+
+	/* Start monitoring */
+	via686a_write_value(client, VIA686A_REG_CONFIG, 0x01);
+
+	/* Cofigure temp interrupt mode for continuous-interrupt operation */
+	via686a_write_value(client, VIA686A_REG_TEMP_MODE, 
+			    via686a_read_value(client, VIA686A_REG_TEMP_MODE) &
+			    !(VIA686A_TEMP_MODE_MASK | VIA686A_TEMP_MODE_CONTINUOUS));
+}
+
+static void via686a_update_client(struct i2c_client *client)
+{
+	struct via686a_data *data = i2c_get_clientdata(client);
+	int i;
+
+	down(&data->update_lock);
+
+       if ((jiffies - data->last_updated > HZ + HZ / 2) ||
+           (jiffies < data->last_updated) || !data->valid) {
+
+		for (i = 0; i <= 4; i++) {
+			data->in[i] =
+			    via686a_read_value(client, VIA686A_REG_IN(i));
+			data->in_min[i] = via686a_read_value(client,
+							     VIA686A_REG_IN_MIN
+							     (i));
+			data->in_max[i] =
+			    via686a_read_value(client, VIA686A_REG_IN_MAX(i));
+		}
+		for (i = 1; i <= 2; i++) {
+			data->fan[i - 1] =
+			    via686a_read_value(client, VIA686A_REG_FAN(i));
+			data->fan_min[i - 1] = via686a_read_value(client,
+						     VIA686A_REG_FAN_MIN(i));
+		}
+		for (i = 1; i <= 3; i++) {
+			data->temp[i - 1] = via686a_read_value(client,
+						 VIA686A_REG_TEMP(i)) << 2;
+			data->temp_over[i - 1] =
+			    via686a_read_value(client,
+					       VIA686A_REG_TEMP_OVER(i));
+			data->temp_hyst[i - 1] =
+			    via686a_read_value(client,
+					       VIA686A_REG_TEMP_HYST(i));
+		}
+		/* add in lower 2 bits 
+		   temp1 uses bits 7-6 of VIA686A_REG_TEMP_LOW1
+		   temp2 uses bits 5-4 of VIA686A_REG_TEMP_LOW23
+		   temp3 uses bits 7-6 of VIA686A_REG_TEMP_LOW23
+		 */
+		data->temp[0] |= (via686a_read_value(client,
+						     VIA686A_REG_TEMP_LOW1)
+				  & 0xc0) >> 6;
+		data->temp[1] |=
+		    (via686a_read_value(client, VIA686A_REG_TEMP_LOW23) &
+		     0x30) >> 4;
+		data->temp[2] |=
+		    (via686a_read_value(client, VIA686A_REG_TEMP_LOW23) &
+		     0xc0) >> 6;
+
+		i = via686a_read_value(client, VIA686A_REG_FANDIV);
+		data->fan_div[0] = (i >> 4) & 0x03;
+		data->fan_div[1] = i >> 6;
+		data->alarms =
+		    via686a_read_value(client,
+				       VIA686A_REG_ALARM1) |
+		    (via686a_read_value(client, VIA686A_REG_ALARM2) << 8);
+		data->last_updated = jiffies;
+		data->valid = 1;
+	}
+
+	up(&data->update_lock);
+}
+
+
+/* The next few functions are the call-back functions of the /proc/sys and
+   sysctl files. Which function is used is defined in the ctl_table in
+   the extra1 field.
+   Each function must return the magnitude (power of 10 to divide the date
+   with) if it is called with operation==SENSORS_PROC_REAL_INFO. It must
+   put a maximum of *nrels elements in results reflecting the data of this
+   file, and set *nrels to the number it actually put in it, if operation==
+   SENSORS_PROC_REAL_READ. Finally, it must get upto *nrels elements from
+   results and write them to the chip, if operations==SENSORS_PROC_REAL_WRITE.
+   Note that on SENSORS_PROC_REAL_READ, I do not check whether results is
+   large enough (by checking the incoming value of *nrels). This is not very
+   good practice, but as long as you put less than about 5 values in results,
+   you can assume it is large enough. */
+static void via686a_in(struct i2c_client *client, int operation, int ctl_name,
+               int *nrels_mag, long *results)
+{
+	struct via686a_data *data = i2c_get_clientdata(client);
+	int nr = ctl_name - VIA686A_SYSCTL_IN0;
+
+	if (operation == SENSORS_PROC_REAL_INFO)
+		*nrels_mag = 2;
+	else if (operation == SENSORS_PROC_REAL_READ) {
+		via686a_update_client(client);
+		results[0] = IN_FROM_REG(data->in_min[nr], nr);
+		results[1] = IN_FROM_REG(data->in_max[nr], nr);
+		results[2] = IN_FROM_REG(data->in[nr], nr);
+		*nrels_mag = 3;
+	} else if (operation == SENSORS_PROC_REAL_WRITE) {
+		if (*nrels_mag >= 1) {
+			data->in_min[nr] = IN_TO_REG(results[0], nr);
+			via686a_write_value(client, VIA686A_REG_IN_MIN(nr),
+					    data->in_min[nr]);
+		}
+		if (*nrels_mag >= 2) {
+			data->in_max[nr] = IN_TO_REG(results[1], nr);
+			via686a_write_value(client, VIA686A_REG_IN_MAX(nr),
+					    data->in_max[nr]);
+		}
+	}
+}
+
+void via686a_fan(struct i2c_client *client, int operation, int ctl_name,
+		 int *nrels_mag, long *results)
+{
+	struct via686a_data *data = i2c_get_clientdata(client);
+	int nr = ctl_name - VIA686A_SYSCTL_FAN1 + 1;
+
+	if (operation == SENSORS_PROC_REAL_INFO)
+		*nrels_mag = 0;
+	else if (operation == SENSORS_PROC_REAL_READ) {
+		via686a_update_client(client);
+		results[0] = FAN_FROM_REG(data->fan_min[nr - 1],
+					  DIV_FROM_REG(data->fan_div
+						       [nr - 1]));
+		results[1] = FAN_FROM_REG(data->fan[nr - 1],
+				 DIV_FROM_REG(data->fan_div[nr - 1]));
+		*nrels_mag = 2;
+	} else if (operation == SENSORS_PROC_REAL_WRITE) {
+		if (*nrels_mag >= 1) {
+			data->fan_min[nr - 1] = FAN_TO_REG(results[0], 
+							   DIV_FROM_REG(data->
+							      fan_div[nr -1]));
+			via686a_write_value(client,
+					    VIA686A_REG_FAN_MIN(nr),
+					    data->fan_min[nr - 1]);
+		}
+	}
+}
+
+void via686a_temp(struct i2c_client *client, int operation, int ctl_name,
+		  int *nrels_mag, long *results)
+{
+	struct via686a_data *data = i2c_get_clientdata(client);
+	int nr = ctl_name - VIA686A_SYSCTL_TEMP;
+
+	if (operation == SENSORS_PROC_REAL_INFO)
+		*nrels_mag = 1;
+	else if (operation == SENSORS_PROC_REAL_READ) {
+		via686a_update_client(client);
+		results[0] = TEMP_FROM_REG(data->temp_over[nr]);
+		results[1] = TEMP_FROM_REG(data->temp_hyst[nr]);
+		results[2] = TEMP_FROM_REG10(data->temp[nr]);
+		*nrels_mag = 3;
+	} else if (operation == SENSORS_PROC_REAL_WRITE) {
+		if (*nrels_mag >= 1) {
+			data->temp_over[nr] = TEMP_TO_REG(results[0]);
+			via686a_write_value(client,
+					    VIA686A_REG_TEMP_OVER(nr + 1),
+					    data->temp_over[nr]);
+		}
+		if (*nrels_mag >= 2) {
+			data->temp_hyst[nr] = TEMP_TO_REG(results[1]);
+			via686a_write_value(client,
+					    VIA686A_REG_TEMP_HYST(nr + 1),
+					    data->temp_hyst[nr]);
+		}
+	}
+}
+
+void via686a_alarms(struct i2c_client *client, int operation, int ctl_name,
+		    int *nrels_mag, long *results)
+{
+	struct via686a_data *data = i2c_get_clientdata(client);
+	if (operation == SENSORS_PROC_REAL_INFO)
+		*nrels_mag = 0;
+	else if (operation == SENSORS_PROC_REAL_READ) {
+		via686a_update_client(client);
+		results[0] = ALARMS_FROM_REG(data->alarms);
+		*nrels_mag = 1;
+	}
+}
+
+void via686a_fan_div(struct i2c_client *client, int operation,
+		     int ctl_name, int *nrels_mag, long *results)
+{
+	struct via686a_data *data = i2c_get_clientdata(client);
+	int old;
+
+	if (operation == SENSORS_PROC_REAL_INFO)
+		*nrels_mag = 0;
+	else if (operation == SENSORS_PROC_REAL_READ) {
+		via686a_update_client(client);
+		results[0] = DIV_FROM_REG(data->fan_div[0]);
+		results[1] = DIV_FROM_REG(data->fan_div[1]);
+		*nrels_mag = 2;
+	} else if (operation == SENSORS_PROC_REAL_WRITE) {
+		old = via686a_read_value(client, VIA686A_REG_FANDIV);
+		if (*nrels_mag >= 2) {
+			data->fan_div[1] = DIV_TO_REG(results[1]);
+			old = (old & 0x3f) | (data->fan_div[1] << 6);
+		}
+		if (*nrels_mag >= 1) {
+			data->fan_div[0] = DIV_TO_REG(results[0]);
+			old = (old & 0xcf) | (data->fan_div[0] << 4);
+			via686a_write_value(client, VIA686A_REG_FANDIV,
+					    old);
+		}
+	}
+}
+
+
+static struct pci_device_id via686a_pci_ids[] __devinitdata = {
+       {
+	       .vendor 		= PCI_VENDOR_ID_VIA, 
+	       .device 		= PCI_DEVICE_ID_VIA_82C686_4, 
+	       .subvendor	= PCI_ANY_ID, 
+	       .subdevice	= PCI_ANY_ID, 
+	       .class		= 0, 
+	       .class_mask	= 0, 
+	       .driver_data	= 0, 
+       },
+       { 0, }
+};
+
+static int __devinit via686a_pci_probe(struct pci_dev *dev,
+                                      const struct pci_device_id *id)
+{
+       u16 val;
+       int addr = 0;
+
+       if (PCIBIOS_SUCCESSFUL !=
+           pci_read_config_word(dev, VIA686A_BASE_REG, &val))
+               return -ENODEV;
+
+       addr = val & ~(VIA686A_EXTENT - 1);
+       if (addr == 0 && force_addr == 0) {
+               dev_err(&dev->dev,"base address not set - upgrade BIOS or use force_addr=0xaddr\n");
+               return -ENODEV;
+       }
+       if (force_addr)
+               addr = force_addr;      /* so detect will get called */
+
+       if (!addr) {
+               dev_err(&dev->dev,"No Via 686A sensors found.\n");
+               return -ENODEV;
+       }
+       normal_isa[0] = addr;
+       s_bridge = dev;
+       return i2c_add_driver(&via686a_driver);
+}
+
+static void __devexit via686a_pci_remove(struct pci_dev *dev)
+{
+       i2c_del_driver(&via686a_driver);
+}
+
+static struct pci_driver via686a_pci_driver = {
+       .name		= "via686a",
+       .id_table	= via686a_pci_ids,
+       .probe		= via686a_pci_probe,
+       .remove		= __devexit_p(via686a_pci_remove),
+};
+
+static int __init sm_via686a_init(void)
+{
+       return pci_module_init(&via686a_pci_driver);
+}
+
+static void __exit sm_via686a_exit(void)
+{
+       pci_unregister_driver(&via686a_pci_driver);
+}
+
+MODULE_AUTHOR("Ky�sti M�lkki <kmalkki@cc.hut.fi>, "
+              "Mark Studebaker <mdsxyz123@yahoo.com> "
+             "and Bob Dougherty <bobd@stanford.edu>");
+MODULE_DESCRIPTION("VIA 686A Sensor device");
+MODULE_LICENSE("GPL");
+
+module_init(sm_via686a_init);
+module_exit(sm_via686a_exit);