land: Add KeyDisabler

* Use common procfs node for it (/proc/touchpanel/capacitive_keys_enable)

Change-Id: I18fa56ca7f1409df37c15482cd8894345da09c03

board/hardware.mk

@@ -1,4 +1,5 @@
 # CM Hardware
 BOARD_USES_CYANOGEN_HARDWARE := true
 BOARD_HARDWARE_CLASS += \
-    hardware/cyanogen/cmhw
+    hardware/cyanogen/cmhw \
+    device/xiaomi/land/cmhw

cmhw/org/cyanogenmod/hardware/KeyDisabler.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2017 The LineageOS Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.cyanogenmod.hardware;
+
+import org.cyanogenmod.internal.util.FileUtils;
+
+/*
+ * Disable capacitive keys
+ *
+ * This is intended for use on devices in which the capacitive keys
+ * can be fully disabled for replacement with a soft navbar. You
+ * really should not be using this on a device with mechanical or
+ * otherwise visible-when-inactive keys
+ */
+
+public class KeyDisabler {
+
+    private static String CONTROL_PATH = "/proc/touchpanel/capacitive_keys_enable";
+
+    public static boolean isSupported() {
+        return FileUtils.isFileWritable(CONTROL_PATH);
+    }
+
+    public static boolean isActive() {
+        return FileUtils.readOneLine(CONTROL_PATH).equals("0");
+    }
+
+    public static boolean setActive(boolean state) {
+        return FileUtils.writeLine(CONTROL_PATH, (state ? "1" : "0"));
+    }
+
+}

rootdir/init.qcom.sh

@@ -26,6 +26,9 @@
 # ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #
 
+# Set shared touchpanel nodes ownership (these are proc_symlinks to the real sysfs nodes)
+chown -LR system.system /proc/touchpanel
+
 #
 # Make modem config folder and copy firmware config to that folder for RIL
 #