hwmon: (mc13783-adc) Add support for the MC13892 PMIC

Based on a patch by David Jander that mostly did s/mc13783/mc13xxx/ .

Additionally use dev_get_drvdata instead of to_platform_device +
platform_get_drvdata in mc13783_adc_read (spotted by Jean Delvare).

Cc: David Jander <david.jander@protonic.nl>
Signed-off-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/Documentation/hwmon/mc13783-adc b/Documentation/hwmon/mc13783-adc
index 044531a..d0e7b3f 100644
--- a/Documentation/hwmon/mc13783-adc
+++ b/Documentation/hwmon/mc13783-adc
@@ -3,8 +3,11 @@
 
 Supported chips:
   * Freescale Atlas MC13783
-    Prefix: 'mc13783_adc'
+    Prefix: 'mc13783'
     Datasheet: http://www.freescale.com/files/rf_if/doc/data_sheet/MC13783.pdf?fsrch=1
+  * Freescale Atlas MC13892
+    Prefix: 'mc13892'
+    Datasheet: http://cache.freescale.com/files/analog/doc/data_sheet/MC13892.pdf?fsrch=1&sr=1
 
 Authors:
     Sascha Hauer <s.hauer@pengutronix.de>
@@ -13,20 +16,21 @@
 Description
 -----------
 
-The Freescale MC13783 is a Power Management and Audio Circuit. Among
-other things it contains a 10-bit A/D converter. The converter has 16
-channels which can be used in different modes.
-The A/D converter has a resolution of 2.25mV. Channels 0-4 have
-a dedicated meaning with chip internal scaling applied. Channels 5-7
-can be used as general purpose inputs or alternatively in a dedicated
-mode. Channels 12-15 are occupied by the touchscreen if it's active.
+The Freescale MC13783 and MC13892 are Power Management and Audio Circuits.
+Among other things they contain a 10-bit A/D converter. The converter has 16
+(MC13783) resp. 12 (MC13892) channels which can be used in different modes. The
+A/D converter has a resolution of 2.25mV.
 
-Currently the driver only supports channels 2 and 5-15 with no alternative
-modes for channels 5-7.
+Some channels can be used as General Purpose inputs or in a dedicated mode with
+a chip internal scaling applied .
 
-See this table for the meaning of the different channels and their chip
-internal scaling:
+Currently the driver only supports the Application Supply channel (BP / BPSNS),
+the General Purpose inputs and touchscreen.
 
+See the following tables for the meaning of the different channels and their
+chip internal scaling:
+
+MC13783:
 Channel	Signal						Input Range	Scaling
 -------------------------------------------------------------------------------
 0	Battery Voltage (BATT)				2.50 - 4.65V	-2.40V
@@ -34,7 +38,7 @@
 2	Application Supply (BP)				2.50 - 4.65V	-2.40V
 3	Charger Voltage (CHRGRAW)			0 - 10V /	/5
 							0 - 20V		/10
-4	Charger Current (CHRGISNSP-CHRGISNSN)		-0.25V - 0.25V	x4
+4	Charger Current (CHRGISNSP-CHRGISNSN)		-0.25 - 0.25V	x4
 5	General Purpose ADIN5 / Battery Pack Thermistor	0 - 2.30V	No
 6	General Purpose ADIN6 / Backup Voltage (LICELL)	0 - 2.30V /	No /
 							1.50 - 3.50V	-1.20V
@@ -48,3 +52,23 @@
 13	General Purpose TSX2 / Touchscreen X-plate 2	0 - 2.30V	No
 14	General Purpose TSY1 / Touchscreen Y-plate 1	0 - 2.30V	No
 15	General Purpose TSY2 / Touchscreen Y-plate 2	0 - 2.30V	No
+
+MC13892:
+Channel	Signal						Input Range	Scaling
+-------------------------------------------------------------------------------
+0	Battery Voltage (BATT)				0 - 4.8V	/2
+1	Battery Current (BATT - BATTISNSCC)		-60 - 60 mV	x20
+2	Application Supply (BPSNS)			0 - 4.8V	/2
+3	Charger Voltage (CHRGRAW)			0 - 12V /	/5
+							0 - 20V		/10
+4	Charger Current (CHRGISNS-BPSNS) /		-0.3 - 0.3V /	x4 /
+	Touchscreen X-plate 1				0 - 2.4V	No
+5	General Purpose ADIN5 /	Battery Pack Thermistor	0 - 2.4V	No
+6	General Purpose ADIN6 / Backup Voltage (LICELL)	0 - 2.4V /	No
+	Backup Voltage (LICELL)                        	0 - 3.6V	x2/3
+7	General Purpose ADIN7 / UID / Die Temperature	0 - 2.4V /	No /
+							0 - 4.8V	/2
+12	General Purpose TSX1 / Touchscreen X-plate 1	0 - 2.4V	No
+13	General Purpose TSX2 / Touchscreen X-plate 2	0 - 2.4V	No
+14	General Purpose TSY1 / Touchscreen Y-plate 1	0 - 2.4V	No
+15	General Purpose TSY2 / Touchscreen Y-plate 2	0 - 2.4V	No