From: Douglas Anderson <dianders@chromium.org>
Date: Fri, 22 Apr 2016 18:32:48 +0000 (-0700)
Subject: ARM64: dts: rk3399: add trackpad for gru/kevin boards
X-Git-Tag: firefly_0821_release~2718
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=b67caebc9470b9785a4ec28030fba7df7f85d99a;p=firefly-linux-kernel-4.4.55.git

ARM64: dts: rk3399: add trackpad for gru/kevin boards

The trackpad bits in the DTS needed some love.  This adds some basic
infrastructure support in the main gru dts file and then adds the
specific trackpad used on kevin-r0 and kevin-r1.  For now just duplicate
between kevin-r0 and kevin-r1 and we'll decide if we want to share
later (perhaps we want an "atmel" snippet?).

Note that gpio-keymap here makes the driver appear as a trackpad rather
than a touchscreen (driver assumes that anything with buttons is a
trackpad).  Input entry corresponding to the button on the trackpad was
found by experimentation as suggested in the device tree bindings.

BUG=chrome-os-partner:52637
TEST=With series, trackpad works in browser; button works.

Change-Id: Ia62cff90449625778fd99054b914e22a55c13550
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-on: https://chrome-internal-review.googlesource.com/256510
Commit-Ready: Doug Anderson <dianders@google.com>
Tested-by: Doug Anderson <dianders@google.com>
Reviewed-by: Brian Norris <briannorris@google.com>
Signed-off-by: Caesar Wang <wxt@rock-chips.com>
---

diff --git a/arch/arm64/boot/dts/rockchip/rk3399-gru-kevin-r0.dts b/arch/arm64/boot/dts/rockchip/rk3399-gru-kevin-r0.dts
index 84d2c6990694..78fe59da7085 100644
--- a/arch/arm64/boot/dts/rockchip/rk3399-gru-kevin-r0.dts
+++ b/arch/arm64/boot/dts/rockchip/rk3399-gru-kevin-r0.dts
@@ -51,6 +51,21 @@
 		     "google,kevin", "google,gru", "rockchip,rk3399";
 };
 
+&ap_i2c_tp {
+	trackpad@4a {
+		compatible = "atmel,maxtouch";
+		reg = <0x4a>;
+		pinctrl-names = "default";
+		pinctrl-0 = <&trackpad_int_l>;
+		interrupt-parent = <&gpio1>;
+		interrupts = <4 IRQ_TYPE_LEVEL_LOW>;
+		linux,gpio-keymap = <KEY_RESERVED
+				     KEY_RESERVED
+				     KEY_RESERVED
+				     BTN_LEFT>;
+	};
+};
+
 /* GPIO overrides for -r0; in same order as parent */
 
 &pp3000 {
diff --git a/arch/arm64/boot/dts/rockchip/rk3399-gru-kevin-r1.dts b/arch/arm64/boot/dts/rockchip/rk3399-gru-kevin-r1.dts
index 858e80397841..3ae059f34cb4 100644
--- a/arch/arm64/boot/dts/rockchip/rk3399-gru-kevin-r1.dts
+++ b/arch/arm64/boot/dts/rockchip/rk3399-gru-kevin-r1.dts
@@ -58,6 +58,21 @@
 		     "google,gru", "rockchip,rk3399";
 };
 
+&ap_i2c_tp {
+	trackpad@4a {
+		compatible = "atmel,maxtouch";
+		reg = <0x4a>;
+		pinctrl-names = "default";
+		pinctrl-0 = <&trackpad_int_l>;
+		interrupt-parent = <&gpio1>;
+		interrupts = <4 IRQ_TYPE_LEVEL_LOW>;
+		linux,gpio-keymap = <KEY_RESERVED
+				     KEY_RESERVED
+				     KEY_RESERVED
+				     BTN_LEFT>;
+	};
+};
+
 /* PINCTRL: always below everything else */
 
 &pinctrl {
diff --git a/arch/arm64/boot/dts/rockchip/rk3399-gru.dtsi b/arch/arm64/boot/dts/rockchip/rk3399-gru.dtsi
index ba69a950c219..43d3fa8df8d8 100644
--- a/arch/arm64/boot/dts/rockchip/rk3399-gru.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3399-gru.dtsi
@@ -42,6 +42,7 @@
  *     OTHER DEALINGS IN THE SOFTWARE.
  */
 
+#include <dt-bindings/input/input.h>
 #include <dt-bindings/pwm/pwm.h>
 #include "rk3399.dtsi"
 
@@ -575,6 +576,8 @@ ap_i2c_ts: &i2c3 {
 };
 
 ap_i2c_tp: &i2c5 {
+	status = "okay";
+
 	/*
 	 * Note strange pullup enable.  Apparently this avoids leakage but
 	 * still allows us to get nice 4.7K pullups for high speed i2c
@@ -583,13 +586,11 @@ ap_i2c_tp: &i2c5 {
 	 */
 	pinctrl-0 = <&i2c5_xfer &ap_i2c_tp_pu_en>;
 
-	status = "okay";
+	clock-frequency = <400000>;
 
-	// TODO: bus speed
-	//       ...with no speed, it should just use 100kHz
-	// TODO: rise / fall times?
-
-	// TODO: Add the proper touchpanel reference...
+	/* These are relatively safe rise/fall times; TODO: measure */
+	i2c-scl-falling-time-ns = <50>;
+	i2c-scl-rising-time-ns = <300>;
 };
 
 ap_i2c_audio: &i2c8 {
@@ -1051,10 +1052,14 @@ ap_i2c_audio: &i2c8 {
 		};
 	};
 
-	touchpanel {
+	trackpad {
 		ap_i2c_tp_pu_en: ap-i2c-tp-pu-en {
 			rockchip,pins = <3 12 RK_FUNC_GPIO &pcfg_output_high>;
 		};
+
+		trackpad_int_l: trackpad-int-l {
+			rockchip,pins = <1 4 RK_FUNC_GPIO &pcfg_pull_up>;
+		};
 	};
 
 	backlight-enable {