hwmon: (pmbus) Add support for Intersil power management chips

Add support for Intersil / Zilker Labs ZL2004, ZL2006, ZL2008, ZL2105, ZL2106,
ZL6100, and ZL6105.

Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Reviewed-by: Robert Coulson <robert.coulson@ericsson.com>

Documentation/hwmon/zl6100

@@ -0,0 +1,125 @@
+Kernel driver zl6100
+====================
+
+Supported chips:
+  * Intersil / Zilker Labs ZL2004
+    Prefix: 'zl2004'
+    Addresses scanned: -
+    Datasheet: http://www.intersil.com/data/fn/fn6847.pdf
+  * Intersil / Zilker Labs ZL2006
+    Prefix: 'zl2006'
+    Addresses scanned: -
+    Datasheet: http://www.intersil.com/data/fn/fn6850.pdf
+  * Intersil / Zilker Labs ZL2008
+    Prefix: 'zl2008'
+    Addresses scanned: -
+    Datasheet: http://www.intersil.com/data/fn/fn6859.pdf
+  * Intersil / Zilker Labs ZL2105
+    Prefix: 'zl2105'
+    Addresses scanned: -
+    Datasheet: http://www.intersil.com/data/fn/fn6851.pdf
+  * Intersil / Zilker Labs ZL2106
+    Prefix: 'zl2106'
+    Addresses scanned: -
+    Datasheet: http://www.intersil.com/data/fn/fn6852.pdf
+  * Intersil / Zilker Labs ZL6100
+    Prefix: 'zl6100'
+    Addresses scanned: -
+    Datasheet: http://www.intersil.com/data/fn/fn6876.pdf
+  * Intersil / Zilker Labs ZL6105
+    Prefix: 'zl6105'
+    Addresses scanned: -
+    Datasheet: http://www.intersil.com/data/fn/fn6906.pdf
+
+Author: Guenter Roeck <guenter.roeck@ericsson.com>
+
+
+Description
+-----------
+
+This driver supports hardware montoring for Intersil / Zilker Labs ZL6100 and
+compatible digital DC-DC controllers.
+
+The driver is a client driver to the core PMBus driver. Please see
+Documentation/hwmon/pmbus and Documentation.hwmon/pmbus-core for details
+on PMBus client drivers.
+
+
+Usage Notes
+-----------
+
+This driver does not auto-detect devices. You will have to instantiate the
+devices explicitly. Please see Documentation/i2c/instantiating-devices for
+details.
+
+WARNING: Do not access chip registers using the i2cdump command, and do not use
+any of the i2ctools commands on a command register used to save and restore
+configuration data (0x11, 0x12, 0x15, 0x16, and 0xf4). The chips supported by
+this driver interpret any access to those command registers (including read
+commands) as request to execute the command in question. Unless write accesses
+to those registers are protected, this may result in power loss, board resets,
+and/or Flash corruption. Worst case, your board may turn into a brick.
+
+
+Platform data support
+---------------------
+
+The driver supports standard PMBus driver platform data.
+
+
+Module parameters
+-----------------
+
+delay
+-----
+
+Some Intersil/Zilker Labs DC-DC controllers require a minimum interval between
+I2C bus accesses. According to Intersil, the minimum interval is 2 ms, though
+1 ms appears to be sufficient and has not caused any problems in testing.
+The problem is known to affect ZL6100, ZL2105, and ZL2008. It is known not to
+affect ZL2004 and ZL6105. The driver automatically sets the interval to 1 ms
+except for ZL2004 and ZL6105. To enable manual override, the driver provides a
+writeable module parameter, 'delay', which can be used to set the interval to
+a value between 0 and 65,535 microseconds.
+
+
+Sysfs entries
+-------------
+
+The following attributes are supported. Limits are read-write; all other
+attributes are read-only.
+
+in1_label		"vin"
+in1_input		Measured input voltage.
+in1_min			Minimum input voltage.
+in1_max			Maximum input voltage.
+in1_lcrit		Critical minumum input voltage.
+in1_crit		Critical maximum input voltage.
+in1_min_alarm		Input voltage low alarm.
+in1_max_alarm		Input voltage high alarm.
+in1_lcrit_alarm		Input voltage critical low alarm.
+in1_crit_alarm		Input voltage critical high alarm.
+
+in2_label		"vout1"
+in2_input		Measured output voltage.
+in2_lcrit		Critical minumum output Voltage.
+in2_crit		Critical maximum output voltage.
+in2_lcrit_alarm		Critical output voltage critical low alarm.
+in2_crit_alarm		Critical output voltage critical high alarm.
+
+curr1_label		"iout1"
+curr1_input		Measured output current.
+curr1_lcrit		Critical minimum output current.
+curr1_crit		Critical maximum output current.
+curr1_lcrit_alarm	Output current critical low alarm.
+curr1_crit_alarm	Output current critical high alarm.
+
+temp[12]_input		Measured temperature.
+temp[12]_min		Minimum temperature.
+temp[12]_max		Maximum temperature.
+temp[12]_lcrit		Critical low temperature.
+temp[12]_crit		Critical high temperature.
+temp[12]_min_alarm	Chip temperature low alarm.
+temp[12]_max_alarm	Chip temperature high alarm.
+temp[12]_lcrit_alarm	Chip temperature critical low alarm.
+temp[12]_crit_alarm	Chip temperature critical high alarm.