Input: add Broadcom iProc touchscreen driver

Add initial version of the Broadcom touchscreen driver.
Reviewed-by: Ray Jui <rjui@broadcom.com>
Reviewed-by: Scott Branden <sbranden@broadcom.com>
Tested-by: Scott Branden <sbranden@broadcom.com>
Signed-off-by: Jonathan Richardson <jonathar@broadcom.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Documentation/devicetree/bindings/input/touchscreen/brcm,iproc-touchscreen.txt

+* Broadcom's IPROC Touchscreen Controller
+
+Required properties:
+- compatible: must be "brcm,iproc-touchscreen"
+- reg: physical base address of the controller and length of memory mapped
+  region.
+- clocks:  The clock provided by the SOC to driver the tsc
+- clock-name:  name for the clock
+- interrupts: The touchscreen controller's interrupt
+
+Optional properties:
+- scanning_period: Time between scans. Each step is 1024 us.  Valid 1-256.
+- debounce_timeout: Each step is 512 us.  Valid 0-255
+- settling_timeout: The settling duration (in ms) is the amount of time
+                    the tsc waits to allow the voltage to settle after
+                    turning on the drivers in detection mode.
+                    Valid values: 0-11
+                    0 =  0.008 ms
+                    1 =  0.01 ms
+                    2 =  0.02 ms
+                    3 =  0.04 ms
+                    4 =  0.08 ms
+                    5 =  0.16 ms
+                    6 =  0.32 ms
+                    7 =  0.64 ms
+                    8 =  1.28 ms
+                    9 =  2.56 ms
+                   10 =  5.12 ms
+                   11 = 10.24 ms
+- touch_timeout: The continuous number of scan periods in which touch is
+                not detected before the controller returns to idle state.
+                Valid values 0-255.
+- average_data: Number of data samples which are averaged before a final
+                data point is placed into the FIFO
+                Valid values 0-7
+                0 =   1 sample
+                1 =   2 samples
+                2 =   4 samples
+                3 =   8 samples
+                4 =  16 samples
+                5 =  32 samples
+                6 =  64 samples
+                7 = 128 samples
+- fifo_threshold: Interrupt is generated whenever the number of fifo
+                entries exceeds this value
+                Valid values 0-31
+- touchscreen-size-x: horizontal resolution of touchscreen (in pixels)
+- touchscreen-size-y: vertical resolution of touchscreen (in pixels)
+- touchscreen-fuzz-x: horizontal noise value of the absolute input
+                      device (in pixels)
+- touchscreen-fuzz-y: vertical noise value of the absolute input
+                      device (in pixels)
+- touchscreen-inverted-x: X axis is inverted (boolean)
+- touchscreen-inverted-y: Y axis is inverted (boolean)
+
+Example:
+
+	touchscreen: tsc@0x180A6000 {
+		compatible = "brcm,iproc-touchscreen";
+		#address-cells = <1>;
+		#size-cells = <1>;
+		reg = <0x180A6000 0x40>;
+		clocks = <&adc_clk>;
+		clock-names = "tsc_clk";
+		interrupts = <GIC_SPI 164 IRQ_TYPE_LEVEL_HIGH>;
+
+		scanning_period = <5>;
+		debounce_timeout = <40>;
+		settling_timeout = <7>;
+		touch_timeout = <10>;
+		average_data = <5>;
+		fifo_threshold = <1>;
+		/* Touchscreen is rotated 180 degrees. */
+		touchscreen-inverted-x;
+		touchscreen-inverted-y;
+	};

drivers/input/touchscreen/Kconfig

@@ -324,6 +324,18 @@ config TOUCHSCREEN_ILI210X
 	  To compile this driver as a module, choose M here: the
 	  module will be called ili210x.
 
+config TOUCHSCREEN_IPROC
+	tristate "IPROC touch panel driver support"
+	depends on ARCH_BCM_IPROC || COMPILE_TEST
+	help
+	  Say Y here if you want to add support for the IPROC touch
+	  controller to your system.
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called bcm_iproc_tsc.
+
 config TOUCHSCREEN_S3C2410
 	tristate "Samsung S3C2410/generic touchscreen input driver"
 	depends on ARCH_S3C24XX || SAMSUNG_DEV_TS

drivers/input/touchscreen/Makefile

@@ -39,6 +39,7 @@ obj-$(CONFIG_TOUCHSCREEN_GOODIX)	+= goodix.o
 obj-$(CONFIG_TOUCHSCREEN_ILI210X)	+= ili210x.o
 obj-$(CONFIG_TOUCHSCREEN_INEXIO)	+= inexio.o
 obj-$(CONFIG_TOUCHSCREEN_INTEL_MID)	+= intel-mid-touch.o
+obj-$(CONFIG_TOUCHSCREEN_IPROC)		+= bcm_iproc_tsc.o
 obj-$(CONFIG_TOUCHSCREEN_LPC32XX)	+= lpc32xx_ts.o
 obj-$(CONFIG_TOUCHSCREEN_MAX11801)	+= max11801_ts.o
 obj-$(CONFIG_TOUCHSCREEN_MC13783)	+= mc13783_ts.o