hwmon: (pmbus/zl6100) Add support for VMON/VDRV

Some of the ZL6100 compatible chips support monitoring a separate voltage pin,
VMON (ZL2004) or VDRV (ZL91xx). Report it as in2 / vmon.

The chips support implicit warning limits for VMON/VDRV, as percentage of the
respective critical voltage. Support by reading/writing the critical voltages
and calculating the associated warning voltages.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>

1 files changed, 20 insertions, 6 deletions

diff --git a/Documentation/hwmon/zl6100 b/Documentation/hwmon/zl6100
index a995b41724fd..3d924b6b59e9 100644
--- a/Documentation/hwmon/zl6100
+++ b/Documentation/hwmon/zl6100
@@ -121,12 +121,26 @@ 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 minimum 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.
+in2_label               "vmon"
+in2_input               Measured voltage on VMON (ZL2004) or VDRV (ZL9101M,
+                        ZL9117M) pin. Reported voltage is 16x the voltage on the
+                        pin (adjusted internally by the chip).
+in2_lcrit               Critical minumum VMON/VDRV Voltage.
+in2_crit                Critical maximum VMON/VDRV voltage.
+in2_lcrit_alarm         VMON/VDRV voltage critical low alarm.
+in2_crit_alarm          VMON/VDRV voltage critical high alarm.
+
+                        vmon attributes are supported on ZL2004, ZL9101M,
+                        and ZL9117M only.
+
+inX_label               "vout1"
+inX_input               Measured output voltage.
+inX_lcrit               Critical minimum output Voltage.
+inX_crit                Critical maximum output voltage.
+inX_lcrit_alarm         Critical output voltage critical low alarm.
+inX_crit_alarm          Critical output voltage critical high alarm.
+
+                        X is 3 for ZL2004, ZL9101M, and ZL9117M, 2 otherwise.
 
 curr1_label             "iout1"
 curr1_input             Measured output current.