[LINARO] Add fake touchscreen 'driver' to avoid Android activity crash

Some Android activities like 'Music' expect the presence of touchscreen
device, otherwise they would crash due to lacking of corresponding
system resources.

To fix the crash, a fake touchscreen 'driver' is added, which utilizes
uinput to register a touchscreen device in kernel.

2 files changed, 106 insertions, 0 deletions

diff --git a/fake-ts/Android.mk b/fake-ts/Android.mk
new file mode 100644
index 0000000..3c3ba4c
--- /dev/null
+++ b/fake-ts/Android.mk
@@ -0,0 +1,30 @@
+# Copyright (C) 2011 Linaro Limited
+#
+# 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.
+
+LOCAL_PATH:= $(call my-dir)
+
+ifneq ($(TARGET_SIMULATOR),true)
+
+include $(CLEAR_VARS)
+
+LOCAL_MODULE := faketsd
+
+LOCAL_MODULE_TAGS := optional
+
+LOCAL_SRC_FILES := fake-ts.c
+LOCAL_PRELINK_MODULE := false
+
+include $(BUILD_EXECUTABLE)
+
+endif # !TARGET_SIMULATOR
diff --git a/fake-ts/fake-ts.c b/fake-ts/fake-ts.c
new file mode 100644
index 0000000..9fe0a20
--- /dev/null
+++ b/fake-ts/fake-ts.c
@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2011 Linaro Limited
+ *
+ * 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.
+ */
+
+#include <stdio.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+
+#include <linux/uinput.h>
+
+/* look up source file system/core/init/devices.c for exact node */
+#define UINPUT_DEV "/dev/uinput"
+
+#define DEV_NAME "Fake Touchscreen"
+
+static int uinput_fd = 0;
+
+static void uinput_touch_init(const char* uinput_dev,
+                              const char* dev_name)
+{
+    struct uinput_user_dev dev;
+
+    uinput_fd = open(uinput_dev, O_WRONLY);
+    if (uinput_fd <= 0) {
+        perror("Error opening uinput device.\n");
+        return;
+    }
+    memset(&dev, 0, sizeof(dev));
+    strcpy(dev.name, dev_name);
+    write(uinput_fd, &dev, sizeof(dev));
+
+    /* touch screen event */
+    ioctl(uinput_fd, UI_SET_EVBIT, EV_ABS);
+    ioctl(uinput_fd, UI_SET_ABSBIT, ABS_X);
+    ioctl(uinput_fd, UI_SET_ABSBIT, ABS_Y);
+    ioctl(uinput_fd, UI_SET_EVBIT, EV_KEY);
+    ioctl(uinput_fd, UI_SET_KEYBIT, BTN_TOUCH);
+
+    /* register userspace input device */
+    ioctl(uinput_fd, UI_DEV_CREATE, 0);
+}
+
+static void uinput_touch_deinit()
+{
+    if (uinput_fd > 0) {
+        close(uinput_fd);
+    }
+}
+
+int main(int argc, char* argv[])
+{
+    uinput_touch_init(UINPUT_DEV, DEV_NAME);
+
+    while (1) {
+        sleep(60);
+    }
+
+    uinput_touch_deinit();
+
+    return 0;
+}
+