hwmon: twl4030: Hwmon Driver for TWL4030 MADC

This driver exposes the sysfs nodes of the TWL4030 MADC module.
All the voltage channel values are expressed in terms of mV. Channel 13
and channel 14 are reserved. There are channels which represent
temperature and current the output is represented by celcius
and mA respectively.

Signed-off-by: Keerthy <j-keerthy@ti.com>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 45 insertions, 0 deletions

diff --git a/Documentation/hwmon/twl4030-madc-hwmon b/Documentation/hwmon/twl4030-madc-hwmon
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+Kernel driver twl4030-madc
+=========================
+
+Supported chips:
+        * Texas Instruments TWL4030
+        Prefix: 'twl4030-madc'
+
+
+Authors:
+        J Keerthy <j-keerthy@ti.com>
+
+Description
+-----------
+
+The Texas Instruments TWL4030 is a Power Management and Audio Circuit. Among
+other things it contains a 10-bit A/D converter MADC. The converter has 16
+channels which can be used in different modes.
+
+
+See this table for the meaning of the different channels
+
+Channel Signal
+------------------------------------------
+0       Battery type(BTYPE)
+1       BCI: Battery temperature (BTEMP)
+2       GP analog input
+3       GP analog input
+4       GP analog input
+5       GP analog input
+6       GP analog input
+7       GP analog input
+8       BCI: VBUS voltage(VBUS)
+9       Backup Battery voltage (VBKP)
+10      BCI: Battery charger current (ICHG)
+11      BCI: Battery charger voltage (VCHG)
+12      BCI: Main battery voltage (VBAT)
+13      Reserved
+14      Reserved
+15      VRUSB Supply/Speaker left/Speaker right polarization level
+
+
+The Sysfs nodes will represent the voltage in the units of mV,
+the temperature channel shows the converted temperature in
+degree celcius. The Battery charging current channel represents
+battery charging current in mA.