Driver for Zipit Z2 battery chip

This patch adds driver for Zipit Z2 battery chip called AER915. No
details are known about the chip. The chip is available through I2C bus
at address 0x55 and it's register 0x02 contains battery voltage.

Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index faaa9b4..22f2fa9 100644
--- a/drivers/power/Kconfig
+++ b/drivers/power/Kconfig
@@ -125,6 +125,12 @@
 	  in handheld and portable equipment. The MAX17040 is configured
 	  to operate with a single lithium cell
 
+config BATTERY_Z2
+	tristate "Z2 battery driver"
+	depends on I2C && MACH_ZIPIT2
+	help
+	  Say Y to include support for the battery on the Zipit Z2.
+
 config CHARGER_PCF50633
 	tristate "NXP PCF50633 MBC"
 	depends on MFD_PCF50633