Vibra: Adapt AOSP (default) vibrator HAL into a hardware module.

Android's implementation of vibrator needs to be done inside a
hardware module, so that it can make a vendor implementation possible.

Hw module's name becomes vibrator.default.so.

This change is related to other changes in:
 - frameworks/base
 - hardware/libhardware_legacy
 - device/generic/goldfish
 - platform/build

Change-Id: I844279f5535289f079d412fdc44c5cb3c9c1130c
Author: Vincent Becker <vincentx.becker@intel.com>
Signed-off-by: Vincent Becker <vincentx.becker@intel.com>
Signed-off-by: Shuo Gao <shuo.gao@intel.com>
Signed-off-by: Bruce Beare <bruce.j.beare@intel.com>
Signed-off-by: Jack Ren <jack.ren@intel.com>
Signed-off-by: David Wagner <david.wagner@intel.com>
Author-tracking-BZ: 49760 94611

2 files changed, 165 insertions, 0 deletions

diff --git a/modules/vibrator/Android.mk b/modules/vibrator/Android.mk
new file mode 100644
index 0000000..bbba114
--- /dev/null
+++ b/modules/vibrator/Android.mk
@@ -0,0 +1,30 @@
+# Copyright (C) 2012 The Android Open Source 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.
+
+LOCAL_PATH := $(call my-dir)
+
+include $(CLEAR_VARS)
+
+LOCAL_MODULE := vibrator.default
+
+# HAL module implementation stored in
+# hw/<VIBRATOR_HARDWARE_MODULE_ID>.default.so
+LOCAL_MODULE_PATH := $(TARGET_OUT_SHARED_LIBRARIES)/hw
+LOCAL_C_INCLUDES := hardware/libhardware
+LOCAL_SRC_FILES := vibrator.c
+LOCAL_SHARED_LIBRARIES := liblog
+LOCAL_MODULE_TAGS := optional
+
+include $(BUILD_SHARED_LIBRARY)
+
diff --git a/modules/vibrator/vibrator.c b/modules/vibrator/vibrator.c
new file mode 100644
index 0000000..ce4c03c
--- /dev/null
+++ b/modules/vibrator/vibrator.c
@@ -0,0 +1,135 @@
+/*
+ * Copyright (C) 2013 The Android Open Source 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.
+ */
+
+#include <hardware/vibrator.h>
+#include <hardware/hardware.h>
+
+#include <cutils/log.h>
+
+#include <stdio.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <math.h>
+
+static const char THE_DEVICE[] = "/sys/class/timed_output/vibrator/enable";
+
+static int vibra_exists() {
+    int fd;
+
+    fd = TEMP_FAILURE_RETRY(open(THE_DEVICE, O_RDWR));
+    if(fd < 0) {
+        ALOGE("Vibrator file does not exist : %d", fd);
+        return 0;
+    }
+
+    close(fd);
+    return 1;
+}
+
+static int sendit(unsigned int timeout_ms)
+{
+    int to_write, written, ret, fd;
+
+    char value[20]; /* large enough for millions of years */
+
+    fd = TEMP_FAILURE_RETRY(open(THE_DEVICE, O_RDWR));
+    if(fd < 0) {
+        return -errno;
+    }
+
+    to_write = snprintf(value, sizeof(value), "%u\n", timeout_ms);
+    written = TEMP_FAILURE_RETRY(write(fd, value, to_write));
+
+    if (written == -1) {
+        ret = -errno;
+    } else if (written != to_write) {
+        /* even though EAGAIN is an errno value that could be set
+           by write() in some cases, none of them apply here.  So, this return
+           value can be clearly identified when debugging and suggests the
+           caller that it may try to call vibraror_on() again */
+        ret = -EAGAIN;
+    } else {
+        ret = 0;
+    }
+
+    errno = 0;
+    close(fd);
+
+    return ret;
+}
+
+static int vibra_on(vibrator_device_t* vibradev __unused, unsigned int timeout_ms)
+{
+    /* constant on, up to maximum allowed time */
+    return sendit(timeout_ms);
+}
+
+static int vibra_off(vibrator_device_t* vibradev __unused)
+{
+    return sendit(0);
+}
+
+static int vibra_close(hw_device_t *device)
+{
+    free(device);
+    return 0;
+}
+
+static int vibra_open(const hw_module_t* module, const char* id __unused,
+                      hw_device_t** device __unused) {
+    if (!vibra_exists()) {
+        ALOGE("Vibrator device does not exist. Cannot start vibrator");
+        return -ENODEV;
+    }
+
+    vibrator_device_t *vibradev = calloc(1, sizeof(vibrator_device_t));
+
+    if (!vibradev) {
+        ALOGE("Can not allocate memory for the vibrator device");
+        return -ENOMEM;
+    }
+
+    vibradev->common.tag = HARDWARE_DEVICE_TAG;
+    vibradev->common.module = (hw_module_t *) module;
+    vibradev->common.version = HARDWARE_DEVICE_API_VERSION(1,0);
+    vibradev->common.close = vibra_close;
+
+    vibradev->vibrator_on = vibra_on;
+    vibradev->vibrator_off = vibra_off;
+
+    *device = (hw_device_t *) vibradev;
+
+    return 0;
+}
+
+/*===========================================================================*/
+/* Default vibrator HW module interface definition                           */
+/*===========================================================================*/
+
+static struct hw_module_methods_t vibrator_module_methods = {
+    .open = vibra_open,
+};
+
+struct hw_module_t HAL_MODULE_INFO_SYM = {
+    .tag = HARDWARE_MODULE_TAG,
+    .module_api_version = VIBRATOR_API_VERSION,
+    .hal_api_version = HARDWARE_HAL_API_VERSION,
+    .id = VIBRATOR_HARDWARE_MODULE_ID,
+    .name = "Default vibrator HAL",
+    .author = "The Android Open Source Project",
+    .methods = &vibrator_module_methods,
+};