Input: add support for ChipOne icn8505 based touchscreens

The ChipOne icn8505 is an i2c capacitive touchscreen controller typically
used in cheap x86 tablets, this commit adds a driver for it.

Note the icn8505 is somewhat similar to the icn8318 and I started with
modifying that driver to support both, but in the end the differences were
too large and I decided to write a new driver instead.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

MAINTAINERS

@@ -3441,6 +3441,12 @@ S:	Maintained
 F:	Documentation/devicetree/bindings/input/touchscreen/chipone_icn8318.txt
 F:	drivers/input/touchscreen/chipone_icn8318.c
 
+CHIPONE ICN8505 I2C TOUCHSCREEN DRIVER
+M:	Hans de Goede <hdegoede@redhat.com>
+L:	linux-input@vger.kernel.org
+S:	Maintained
+F:	drivers/input/touchscreen/chipone_icn8505.c
+
 CHROME HARDWARE PLATFORM SUPPORT
 M:	Benson Leung <bleung@chromium.org>
 M:	Olof Johansson <olof@lixom.net>

drivers/input/touchscreen/Kconfig

@@ -164,6 +164,17 @@ config TOUCHSCREEN_CHIPONE_ICN8318
 	  To compile this driver as a module, choose M here: the
 	  module will be called chipone_icn8318.
 
+config TOUCHSCREEN_CHIPONE_ICN8505
+	tristate "chipone icn8505 touchscreen controller"
+	depends on I2C && ACPI
+	help
+	  Say Y here if you have a ChipOne icn8505 based I2C touchscreen.
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called chipone_icn8505.
+
 config TOUCHSCREEN_CY8CTMG110
 	tristate "cy8ctmg110 touchscreen"
 	depends on I2C

drivers/input/touchscreen/Makefile

@@ -19,6 +19,7 @@ obj-$(CONFIG_TOUCHSCREEN_ATMEL_MXT)	+= atmel_mxt_ts.o
 obj-$(CONFIG_TOUCHSCREEN_AUO_PIXCIR)	+= auo-pixcir-ts.o
 obj-$(CONFIG_TOUCHSCREEN_BU21013)	+= bu21013_ts.o
 obj-$(CONFIG_TOUCHSCREEN_CHIPONE_ICN8318)	+= chipone_icn8318.o
+obj-$(CONFIG_TOUCHSCREEN_CHIPONE_ICN8505)	+= chipone_icn8505.o
 obj-$(CONFIG_TOUCHSCREEN_CY8CTMG110)	+= cy8ctmg110_ts.o
 obj-$(CONFIG_TOUCHSCREEN_CYTTSP_CORE)	+= cyttsp_core.o
 obj-$(CONFIG_TOUCHSCREEN_CYTTSP_I2C)	+= cyttsp_i2c.o cyttsp_i2c_common.o