adt7462: new hwmon driver

New driver to play with.  As Jean mentioned a couple of years ago, this
chip is a beast with odd combinations of 8 fans, 4 temperatures, and 13
voltage sensors.  This driver has been tested on an IntelliStation Z30.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

4 files changed, 2080 insertions, 0 deletions

diff --git a/Documentation/hwmon/adt7462 b/Documentation/hwmon/adt7462
new file mode 100644
index 000000000000..ec660b328275
--- /dev/null
+++ b/Documentation/hwmon/adt7462
@@ -0,0 +1,67 @@
+Kernel driver adt7462
+======================
+
+Supported chips:
+  * Analog Devices ADT7462
+    Prefix: 'adt7462'
+    Addresses scanned: I2C 0x58, 0x5C
+    Datasheet: Publicly available at the Analog Devices website
+
+Author: Darrick J. Wong
+
+Description
+-----------
+
+This driver implements support for the Analog Devices ADT7462 chip family.
+
+This chip is a bit of a beast.  It has 8 counters for measuring fan speed.  It
+can also measure 13 voltages or 4 temperatures, or various combinations of the
+two.  See the chip documentation for more details about the exact set of
+configurations.  This driver does not allow one to configure the chip; that is
+left to the system designer.
+
+A sophisticated control system for the PWM outputs is designed into the ADT7462
+that allows fan speed to be adjusted automatically based on any of the three
+temperature sensors. Each PWM output is individually adjustable and
+programmable. Once configured, the ADT7462 will adjust the PWM outputs in
+response to the measured temperatures without further host intervention.  This
+feature can also be disabled for manual control of the PWM's.
+
+Each of the measured inputs (voltage, temperature, fan speed) has
+corresponding high/low limit values. The ADT7462 will signal an ALARM if
+any measured value exceeds either limit.
+
+The ADT7462 samples all inputs continuously. The driver will not read
+the registers more often than once every other second. Further,
+configuration data is only read once per minute.
+
+Special Features
+----------------
+
+The ADT7462 have a 10-bit ADC and can therefore measure temperatures
+with 0.25 degC resolution.
+
+The Analog Devices datasheet is very detailed and describes a procedure for
+determining an optimal configuration for the automatic PWM control.
+
+The driver will report sensor labels when it is able to determine that
+information from the configuration registers.
+
+Configuration Notes
+-------------------
+
+Besides standard interfaces driver adds the following:
+
+* PWM Control
+
+* pwm#_auto_point1_pwm and temp#_auto_point1_temp and
+* pwm#_auto_point2_pwm and temp#_auto_point2_temp -
+
+point1: Set the pwm speed at a lower temperature bound.
+point2: Set the pwm speed at a higher temperature bound.
+
+The ADT7462 will scale the pwm between the lower and higher pwm speed when
+the temperature is between the two temperature boundaries.  PWM values range
+from 0 (off) to 255 (full speed).  Fan speed will be set to maximum when the
+temperature sensor associated with the PWM control exceeds temp#_max.
+
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 1c44f5c47aab..c709e821f04b 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -159,6 +159,16 @@ config SENSORS_ADM9240
           This driver can also be built as a module.  If so, the module
           will be called adm9240.
 
+config SENSORS_ADT7462
+        tristate "Analog Devices ADT7462"
+        depends on I2C && EXPERIMENTAL
+        help
+          If you say yes here you get support for the Analog Devices
+          ADT7462 temperature monitoring chips.
+
+          This driver can also be built as a module. If so, the module
+          will be called adt7462.
+
 config SENSORS_ADT7470
         tristate "Analog Devices ADT7470"
         depends on I2C && EXPERIMENTAL
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index e0d90a68bea0..58fc5be5355d 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -25,6 +25,7 @@ obj-$(CONFIG_SENSORS_ADM1029)	+= adm1029.o
 obj-$(CONFIG_SENSORS_ADM1031)   += adm1031.o
 obj-$(CONFIG_SENSORS_ADM9240)   += adm9240.o
 obj-$(CONFIG_SENSORS_ADS7828)   += ads7828.o
+obj-$(CONFIG_SENSORS_ADT7462)   += adt7462.o
 obj-$(CONFIG_SENSORS_ADT7470)   += adt7470.o
 obj-$(CONFIG_SENSORS_ADT7473)   += adt7473.o
 obj-$(CONFIG_SENSORS_APPLESMC)  += applesmc.o
diff --git a/drivers/hwmon/adt7462.c b/drivers/hwmon/adt7462.c
new file mode 100644
index 000000000000..66107b4dc12a
--- /dev/null
+++ b/drivers/hwmon/adt7462.c
@@ -0,0 +1,2002 @@
+/*
+ * A hwmon driver for the Analog Devices ADT7462
+ * Copyright (C) 2008 IBM
+ *
+ * Author: Darrick J. Wong <djwong@us.ibm.com>
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/module.h>
+#include <linux/jiffies.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+#include <linux/log2.h>
+
+/* Addresses to scan */
+static const unsigned short normal_i2c[] = { 0x58, 0x5C, I2C_CLIENT_END };
+
+/* Insmod parameters */
+I2C_CLIENT_INSMOD_1(adt7462);
+
+/* ADT7462 registers */
+#define ADT7462_REG_DEVICE                      0x3D
+#define ADT7462_REG_VENDOR                      0x3E
+#define ADT7462_REG_REVISION                    0x3F
+
+#define ADT7462_REG_MIN_TEMP_BASE_ADDR          0x44
+#define ADT7462_REG_MIN_TEMP_MAX_ADDR           0x47
+#define ADT7462_REG_MAX_TEMP_BASE_ADDR          0x48
+#define ADT7462_REG_MAX_TEMP_MAX_ADDR           0x4B
+#define ADT7462_REG_TEMP_BASE_ADDR              0x88
+#define ADT7462_REG_TEMP_MAX_ADDR               0x8F
+
+#define ADT7462_REG_FAN_BASE_ADDR               0x98
+#define ADT7462_REG_FAN_MAX_ADDR                0x9F
+#define ADT7462_REG_FAN2_BASE_ADDR              0xA2
+#define ADT7462_REG_FAN2_MAX_ADDR               0xA9
+#define ADT7462_REG_FAN_ENABLE                  0x07
+#define ADT7462_REG_FAN_MIN_BASE_ADDR           0x78
+#define ADT7462_REG_FAN_MIN_MAX_ADDR            0x7F
+
+#define ADT7462_REG_CFG2                        0x02
+#define         ADT7462_FSPD_MASK               0x20
+
+#define ADT7462_REG_PWM_BASE_ADDR               0xAA
+#define ADT7462_REG_PWM_MAX_ADDR                0xAD
+#define ADT7462_REG_PWM_MIN_BASE_ADDR           0x28
+#define ADT7462_REG_PWM_MIN_MAX_ADDR            0x2B
+#define ADT7462_REG_PWM_MAX                     0x2C
+#define ADT7462_REG_PWM_TEMP_MIN_BASE_ADDR      0x5C
+#define ADT7462_REG_PWM_TEMP_MIN_MAX_ADDR       0x5F
+#define ADT7462_REG_PWM_TEMP_RANGE_BASE_ADDR    0x60
+#define ADT7462_REG_PWM_TEMP_RANGE_MAX_ADDR     0x63
+#define         ADT7462_PWM_HYST_MASK           0x0F
+#define         ADT7462_PWM_RANGE_MASK          0xF0
+#define         ADT7462_PWM_RANGE_SHIFT         4
+#define ADT7462_REG_PWM_CFG_BASE_ADDR           0x21
+#define ADT7462_REG_PWM_CFG_MAX_ADDR            0x24
+#define         ADT7462_PWM_CHANNEL_MASK        0xE0
+#define         ADT7462_PWM_CHANNEL_SHIFT       5
+
+#define ADT7462_REG_PIN_CFG_BASE_ADDR           0x10
+#define ADT7462_REG_PIN_CFG_MAX_ADDR            0x13
+#define         ADT7462_PIN7_INPUT              0x01    /* cfg0 */
+#define         ADT7462_DIODE3_INPUT            0x20
+#define         ADT7462_DIODE1_INPUT            0x40
+#define         ADT7462_VID_INPUT               0x80
+#define         ADT7462_PIN22_INPUT             0x04    /* cfg1 */
+#define         ADT7462_PIN21_INPUT             0x08
+#define         ADT7462_PIN19_INPUT             0x10
+#define         ADT7462_