hwmon: Add support for Lattice's POWR1220 power manager IC
This patch adds support for Lattice's POWR1220 power manager IC. Read
access to all the ADCs on the chip are supported through the hwmon
sysfs files.
Signed-off-by: Scott Kanowitz <skanowitz@echo360.com>
[Guenter Roeck: Removed some extra ( )]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
diff --git a/Documentation/hwmon/powr1220 b/Documentation/hwmon/powr1220
new file mode 100644
index 0000000..21e44f7
--- /dev/null
+++ b/Documentation/hwmon/powr1220
@@ -0,0 +1,45 @@
+Kernel driver powr1220
+==================
+
+Supported chips:
+ * Lattice POWR1220AT8
+ Prefix: 'powr1220'
+ Addresses scanned: none
+ Datasheet: Publicly available at the Lattice website
+ http://www.latticesemi.com/
+
+Author: Scott Kanowitz <scott.kanowitz@gmail.com>
+
+Description
+-----------
+
+This driver supports the Lattice POWR1220AT8 chip. The POWR1220
+includes voltage monitoring for 14 inputs as well as trim settings
+for output voltages and GPIOs. This driver implements the voltage
+monitoring portion of the chip.
+
+Voltages are sampled by a 12-bit ADC with a step size of 2 mV.
+An in-line attenuator allows measurements from 0 to 6 V. The
+attenuator is enabled or disabled depending on the setting of the
+input's max value. The driver will enable the attenuator for any
+value over the low measurement range maximum of 2 V.
+
+The input naming convention is as follows:
+
+driver name pin name
+in0 VMON1
+in1 VMON2
+in2 VMON3
+in2 VMON4
+in4 VMON5
+in5 VMON6
+in6 VMON7
+in7 VMON8
+in8 VMON9
+in9 VMON10
+in10 VMON11
+in11 VMON12
+in12 VCCA
+in13 VCCINP
+
+The ADC readings are updated on request with a minimum period of 1s.