auron: add i2c device in acpi for Cypress touch pad

CQ-DEPEND=CL:216362
BRANCH=none
BUG=chrome-os-partner:31494
TEST=build ok, and see touch pad working

Change-Id: I137c02720b45f0e0cc7248680406597de3ce6c8b
Signed-off-by: Kane Chen <kane.chen@intel.com>
Reviewed-on: https://chromium-review.googlesource.com/216356
Reviewed-by: Bernie Thompson <bhthompson@chromium.org>
Tested-by: Bernie Thompson <bhthompson@chromium.org>
Commit-Queue: Bernie Thompson <bhthompson@chromium.org>

src/mainboard/google/auron/acpi/mainboard.asl

@@ -125,4 +125,39 @@ Scope (\_SB.PCI0.I2C0)
 		/* Allow device to power off in S0 */
 		Name (_S0W, 4)
 	}
+
+	Device (CTPA)
+	{
+		Name (_HID, "CYAP0000")
+		Name (_DDN, "Cypress Touchpad")
+		Name (_UID, 3)
+		Name (ISTP, 1) /* Touchpad */
+
+		Name (_CRS, ResourceTemplate()
+		{
+			I2cSerialBus (
+				0x67,                     // SlaveAddress
+				ControllerInitiated,      // SlaveMode
+				400000,                   // ConnectionSpeed
+				AddressingMode7Bit,       // AddressingMode
+				"\\_SB.PCI0.I2C0",             // ResourceSource
+			)
+			Interrupt (ResourceConsumer, Edge, ActiveLow)
+			{
+				BOARD_TRACKPAD_IRQ
+			}
+		})
+
+		Method (_STA)
+		{
+			If (LEqual (\S1EN, 1)) {
+				Return (0xF)
+			} Else {
+				Return (0x0)
+			}
+		}
+
+		/* Allow device to power off in S0 */
+		Name (_S0W, 4)
+	}
 }